CODE OF FEDERAL REGULATIONS40
CONTAINING
A CODIFICATION OF DOCUMENTS
OF GENERAL APPLICABILITY
AND FUTURE EFFECT
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the Office of the Federal Register
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Cite this Code:
The Code of Federal Regulations is a codification of the general and permanent rules published in the Federal Register by the Executive departments and agencies of the Federal Government. The Code is divided into 50 titles which represent broad areas subject to Federal regulation. Each title is divided into chapters which usually bear the name of the issuing agency. Each chapter is further subdivided into parts covering specific regulatory areas.
Each volume of the Code is revised at least once each calendar year and issued on a quarterly basis approximately as follows:
Title 1 through Title 16
Title 17 through Title 27
Title 28 through Title 41
Title 42 through Title 50
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Title 40—
Chapter I—Environmental Protection Agency appears in all twenty-four volumes. A Pesticide Tolerance Commodity/Chemical Index appears in parts 150-189. A Toxic Substances Chemical—CAS Number Index appears in parts 700-789 and part 790 to End. Redesignation Tables appear in the volumes containing parts 50-51, parts 150-189, and parts 700-789. Regulations issued by the Council on Environmental Quality appear in the volume containing part 790 to End. The OMB control numbers for title 40 appear in § 9.1 of this chapter.
For this volume, Linda L. Jones was Chief Editor. The Code of Federal Regulations publication program is under the direction of Frances D. McDonald, assisted by Alomha S. Morris.
(This book contains parts 50 to 51)
Subchapter C—Air Programs is continued in volumes 40 CFR parts 50-51, part 52 (52.01-52.1018), part 52 (52.1019-End), parts 53-59, part 60, parts 61-62, part 63 (63.1-63.1199), part 63 (63.1200-End), parts 64-71, parts 72-80, parts 81-85, part 86, and parts 87-135.
42 U.S.C. 7401,
(a) As used in this part, all terms not defined herein shall have the meaning given them by the Act.
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(a) National primary and secondary ambient air quality standards under section 109 of the Act are set forth in this part.
(b) National primary ambient air quality standards define levels of air quality which the Administrator judges are necessary, with an adequate margin of safety, to protect the public health. National secondary ambient air quality standards define levels of air quality which the Administrator judges necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant. Such standards are subject to revision, and additional primary and secondary standards may be promulgated as the Administrator deems necessary to protect the public health and welfare.
(c) The promulgation of national primary and secondary ambient air quality standards shall not be considered in any manner to allow significant deterioration of existing air quality in any portion of any State or Indian country.
(d) The proposal, promulgation, or revision of national primary and secondary ambient air quality standards shall not prohibit any State or Indian country from establishing ambient air quality standards for that State or area under a tribal CAA program or any portion thereof which are more stringent than the national standards.
All measurements of air quality that are expressed as mass per unit volume (e.g., micrograms per cubic meter) other than for the particulate matter (PM
(a) The level of the annual standard is 0.030 parts per million (ppm), not to be exceeded in a calendar year. The annual arithmetic mean shall be rounded to three decimal places (fractional parts equal to or greater than 0.0005 ppm shall be rounded up).
(b) The level of the 24-hour standard is 0.14 parts per million (ppm), not to be exceeded more than once per calendar year. The 24-hour averages shall be determined from successive nonoverlapping 24-hour blocks starting at midnight each calendar day and shall be rounded to two decimal places (fractional parts equal to or greater than 0.005 ppm shall be rounded up).
(c) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference method described in appendix A to this part or by an equivalent method designated in accordance with part 53 of this chapter.
(d) To demonstrate attainment, the annual arithmetic mean and the second-highest 24-hour averages must be based upon hourly data that are at least 75 percent complete in each calendar quarter. A 24-hour block average shall be considered valid if at least 75 percent of the hourly averages for the 24-hour period are available. In the event that only 18, 19, 20, 21, 22, or 23 hourly averages are available, the 24-hour block average shall be computed as the sum of the available hourly
(a) The level of the 3-hour standard is 0.5 parts per million (ppm), not to be exceeded more than once per calendar year. The 3-hour averages shall be determined from successive nonoverlapping 3-hour blocks starting at midnight each calendar day and shall be rounded to 1 decimal place (fractional parts equal to or greater than 0.05 ppm shall be rounded up).
(b) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference method described in appendix A of this part or by an equivalent method designated in accordance with part 53 of this chapter.
(c) To demonstrate attainment, the second-highest 3-hour average must be based upon hourly data that are at least 75 percent complete in each calendar quarter. A 3-hour block average shall be considered valid only if all three hourly averages for the 3-hour period are available. If only one or two hourly averages are available, but the 3-hour average would exceed the level of the standard when zeros are substituted for the missing values, subject to the rounding rule of paragraph (a) of this section, then this shall be considered a valid 3-hour average. In all cases, the 3-hour block average shall be computed as the sum of the hourly averages divided by 3.
(a) The level of the national primary and secondary 24-hour ambient air quality standards for particulate matter is 150 micrograms per cubic meter (μg/m
(b) The level of the national primary and secondary annual standards for particulate matter is 50 micrograms per cubic meter (μg/m
(c) For the purpose of determining attainment of the primary and secondary standards, particulate matter shall be measured in the ambient air as PM
(1) A reference method based on appendix J and designated in accordance with part 53 of this chapter, or
(2) An equivalent method designated in accordance with part 53 of this chapter.
(d) The PM
(a) The national primary and secondary ambient air quality standards for particulate matter are:
(1) 15.0 micrograms per cubic meter (
(i) A reference method based on appendix L of this part and designated in accordance with part 53 of this chapter; or
(ii) An equivalent method designated in accordance with part 53 of this chapter.
(2) 50 micrograms per cubic meter (
(i) A reference method based on appendix M of this part and designated in accordance with part 53 of this chapter; or
(ii) An equivalent method designated in accordance with part 53 of this chapter.
(b) The annual primary and secondary PM
(c) The 24-hour primary and secondary PM
(d) The annual primary and secondary PM
(e) The 24-hour primary and secondary PM
(a) The national primary ambient air quality standards for carbon monoxide are:
(1) 9 parts per million (10 milligrams per cubic meter) for an 8-hour average concentration not to be exceeded more than once per year and
(2) 35 parts per million (40 milligrams per cubic meter) for a 1-hour average concentration not to be exceeded more than once per year.
(b) The levels of carbon monoxide in the ambient air shall be measured by:
(1) A reference method based on appendix C and designated in accordance with part 53 of this chapter, or
(2) An equivalent method designated in accordance with part 53 of this chapter.
(c) An 8-hour average shall be considered valid if at least 75 percent of the hourly average for the 8-hour period are available. In the event that only six (or seven) hourly averages are available, the 8-hour average shall be computed on the basis of the hours available using six (or seven) as the divisor.
(d) When summarizing data for comparision with the standards, averages shall be stated to one decimal place. Comparison of the data with the levels of the standards in parts per million shall be made in terms of integers with fractional parts of 0.5 or greater rounding up.
(a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured
(b) The 1-hour standards set forth in this section will no longer apply to an area once EPA determines that the area has air quality meeting the 1-hour standard. Area designations are codified in 40 CFR part 81.
(a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by a reference method based on appendix D to this part and designated in accordance with part 53 of this chapter, is 0.08 parts per million (ppm), daily maximum 8-hour average.
(b) The 8-hour primary and secondary ozone ambient air quality standards are met at an ambient air quality monitoring site when the average of the annual fourth-highest daily maximum 8-hour average ozone concentration is less than or equal to 0.08 ppm, as determined in accordance with appendix I to this part.
(a) The level of the national primary ambient air quality standard for nitrogen dioxide is 0.053 parts per million (100 micrograms per cubic meter), annual arithmetic mean concentration.
(b) The level of national secondary ambient air quality standard for nitrogen dioxide is 0.053 parts per million (100 micrograms per cubic meter), annual arithmetic mean concentration.
(c) The levels of the standards shall be measured by:
(1) A reference method based on appendix F and designated in accordance with part 53 of this chapter, or
(2) An equivalent method designated in accordance with part 53 of this chapter.
(d) The standards are attained when the annual arithmetic mean concentration in a calendar year is less than or equal to 0.053 ppm, rounded to three decimal places (fractional parts equal to or greater than 0.0005 ppm must be rounded up). To demonstrate attainment, an annual mean must be based upon hourly data that are at least 75 percent complete or upon data derived from manual methods that are at least 75 percent complete for the scheduled sampling days in each calendar quarter.
National primary and secondary ambient air quality standards for lead and its compounds, measured as elemental lead by a reference method based on appendix G to this part, or by an equivalent method, are: 1.5 micrograms per cubic meter, maximum arithmetic mean averaged over a calendar quarter.
1.0
1.1 This method provides a measurement of the concentration of sulfur dioxide (SO
2.0
2.1 A measured volume of air is bubbled through a solution of 0.04 M potassium tetrachloromercurate (TCM). The SO
3.0
3.1 The lower limit of detection of SO
4.0
4.1 The effects of the principal potential interferences have been minimized or eliminated in the following manner: Nitrogen oxides by the addition of sulfamic acid,(
5.0
5.1 The precision of the analysis is 4.6 percent (at the 95 percent confidence level) based on the analysis of standard sulfite samples.(
5.2 Collaborative test results (
6.0
6.1 By sampling in a controlled temperature environment of 15°
7.0
7.1
7.1.1
7.1.2
7.1.3
7.1.4
7.1.5
7.1.6
7.1.7
7.1.8
7.1.9
7.1.10
7.1.11
7.1.12
7.2
7.2.1
7.3
7.3.1
A standard wavelength filter traceable to the National Bureau of Standards is used to verify the wavelength calibration according to the procedure enclosed with the filter. The wavelength calibration must be verified upon initial receipt of the instrument and after each 160 hours of normal use or every 6 months, whichever occurs first.
7.3.2
7.3.3
7.3.4
7.3.5
8.0
8.1
8.1.1
8.1.2
8.2
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.2.6
8.2.7
8.2.8
8.2.9
8.2.10
8.2.11
This solution is stable for 30 days if kept at 5 °C. (16) If not kept at 5 °C, prepare fresh daily.
8.2.12
8.2.12.1
8.2.12.2
8.2.12.3
1. Place 100 mL each of 1-butanol and 1 N HCl in a large separatory funnel (250-mL) and allow to equilibrate. Note: Certain batches of 1-butanol contain oxidants that create an SO
2. Weigh 100 mg of pararosaniline hydrochloride dye (PRA) in a small beaker. Add 50 mL of the equilibrated acid (drain in acid from the bottom of the separatory funnel in 1.) to the beaker and let stand for several minutes. Discard the remaining acid phase in the separatory funnel.
3. To a 125-mL separatory funnel, add 50 mL of the equilibrated 1-butanol (draw the 1-butanol from the top of the separatory funnel in 1.). Transfer the acid solution (from 2.) containing the dye to the funnel and shake carefully to extract. The violet impurity will transfer to the organic phase.
4. Transfer the lower aqueous phase into another separatory funnel, add 20 mL of equilibrated 1-butanol, and extract again.
5. Repeat the extraction procedure with three more 10-mL portions of equilibrated 1-butanol.
6. After the final extraction, filter the acid phase through a cotton plug into a 50-mL volumetric flask and bring to volume with 1 N HCl. This stock reagent will be a yellowish red.
7. To check the purity of the PRA, perform the assay and adjustment of concentration (Section 8.2.12.4) and prepare a reagent blank (Section 11.2); the absorbance of this reagent blank at 540 nm should be less than 0.170 at 22 °C. If the absorbance is greater than 0.170 under these conditions, further extractions should be performed.
8.2.12.4
1. Prepare 1 M acetate-acetic acid buffer stock solution with a pH of 4.79 by dissolving
2. Pipet 1 mL of the stock PRA solution obtained from the purification process or from a commercial source into a 100-mL volumetric flask and dilute to volume with distilled water.
3. Transfer a 5-mL aliquot of the diluted PRA solution from 2. into a 50-mL volumetric flask. Add 5mL of 1 M acetate-acetic acid buffer solution from 1. and dilute the mixture to volume with distilled water. Let the mixture stand for 1 hour.
4. Measure the absorbance of the above solution at 540 nm with a spectrophotometer against a distilled water reference. Compute the percentage of nominal concentration of PRA by
8.2.13
9.0
9.1
9.2
9.3
9.4
9.4.1
9.4.2
If a barometer is not available, the following equation may be used to determine the barometric pressure:
If the initial flow rate (Q
Invalidate the sample if the difference between the initial (Q
9.5
10.0
10.1
1. Fill all cells with distilled water and designate the one that has the lowest absorbance at 548 nm as the reference. (This reference cell should be marked as such and continually used for this purpose throughout all future analyses.)
2. Zero the spectrophotometer with the reference cell.
3. Determine the absorbance of the remaining cells (A
The corrected absorbance during future analyses using each cell is determining as follows:
10.2
To each volumetric flask, add 1 mL 0.6% sulfamic acid (Section 8.2.1), accurately pipet 2 mL 0.2% formaldehyde solution (Section 8.2.2), then add 5 mL pararosaniline solution (Section 8.2.13). Start a laboratory timer that has been set for 30 minutes. Bring all flasks to volume with recently boiled and cooled distilled water and mix thoroughly. The color must be developed (during the 30-minute period) in a temperature environment in the range of 20° to 30 °C, which is controlled to
A calibration equation is determined using the method of linear least squares (Section 12.1). The total micrograms SO
10.3
10.3.1
Be sure that the total flow rate of the standard exceeds the flow demand of the sample train, with the excess flow vented at atmospheric pressure. Sample each atmosphere using similar apparatus as shown in Figure 1 and under the same conditions as field sampling (i.e., use same absorbing reagent volume and sample same volume of air at an equivalent flow rate). Due to the length of the sampling periods required, this method is not recommended for 24-hour sampling. At the completion of sampling, quantitatively transfer the contents of each impinger to one of a series of 25-mL volumetric flasks (if 10 mL of absorbing solution was used) using small amounts of distilled water for rinse (
Add the remaining reagents for color development in the same manner as in Section 10.2 for static solutions. Calculate a calibration equation and a calibration factor (B
10.3.2 Calibration Option 2B (24-hour samples): Generate a standard atmosphere containing approximately 1,050
At the completion of sampling, bring the absorber solutions to original volume with distilled water. Pipet a 10-mL portion from each absorber into one of a series of 25-mL volumetric flasks. If the color development steps are not to be started within 12 hours of sampling, store the solutions at 5°
Calculate a calibration equation and a calibration factor (B
11.0
11.1
1. For 30-minute or 1-hour samples: Quantitatively transfer the entire 10 mL amount of absorbing solution to a 25-mL volumetric flask and rinse with a small amount (
2. For 24-hour samples: If the volume of the sample is less than the original 50-mL volume (permanent mark on the absorber), adjust the volume back to the original volume with distilled water to compensate for water lost to evaporation during sampling. If the final volume is greater than the original volume, the volume must be measured using a graduated cylinder. To analyze, pipet 10 mL
11.2
1. Allow the sample to stand 20 minutes after the completion of sampling to allow any ozone to decompose (if applicable).
2. To each 25-mL volumetric flask containing reagent blank, sample, or control standard, add 1 mL of 0.6% sulfamic acid (Section 8.2.1) and allow to react for 10 min.
3. Accurately pipet 2 mL of 0.2% formaldehyde solution (Section 8.2.2) and then 5 mL of pararosaniline solution (Section 8.2.13) into each flask. Start a laboratory timer set at 30 minutes.
4. Bring each flask to volume with recently boiled and cooled distilled water and mix thoroughly.
5. During the 30 minutes, the solutions must be in a temperature controlled environment in the range of 20° to 30 °C maintained to
6. After 30 minutes and before 60 minutes, determine the corrected absorbances (equation 10) of each solution at 548 nm using 1-cm optical path length cells against a distilled water reference (Section 10.1). (
7. Do not allow the colored solution to stand in the cells because a film may be deposited. Clean the cells with isopropyl alcohol after use.
8. The reagent blank must be within 0.03 absorbance units of the intercept of the calibration equation determined in Section 10.
11.3
11.4
12.0
12.1
The slope (m), intercept (b), and correlation coefficient (r) are calculated as follows:
A data form (Figure 5) is supplied for easily organizing calibration data when the slope, intercept, and correlation coefficient are calculated by hand.
12.2
12.3
12.4 Control Standards. Calculate the analyzed micrograms of SO
The difference between the true and analyzed values of the control standards must not be greater than 1
12.5 Conversion of
13.0 The TCM absorbing solution and any reagents containing mercury compounds must be treated and disposed of by one of the methods discussed below. Both methods remove greater than 99.99 percent of the mercury.
13.1
13.2
1. Place the waste solution in an uncapped vessel in a hood.
2. For each liter of waste solution, add approximately 10 g of sodium carbonate until neutralization has occurred (NaOH may have to be used).
3. Following neutralization, add 10 g of granular zinc or magnesium.
4. Stir the solution in a hood for 24 hours. Caution must be exercised as hydrogen gas is evolved by this treatment process.
5. After 24 hours, allow the solution to stand without stirring to allow the mercury amalgam (solid black material) to settle to the bottom of the waste receptacle.
6. Upon settling, decant and discard the supernatant liquid.
7. Quantitatively transfer the solid material to a container and allow to dry.
8. The solid material can be sent to a mercury reclaiming plant. It must not be discarded.
13.3
1. Place the waste solution in an uncapped vessel in a hood.
2. For each liter of waste solution, add approximately 10 g of aluminum foil strips. If all the aluminum is consumed and no gas is evolved, add an additional 10 g of foil. Repeat until the foil is no longer consumed and allow the gas to evolve for 24 hours.
3. Decant the supernatant liquid and discard.
4. Transfer the elemental mercury that has settled to the bottom of the vessel to a storage container.
5. The mercury can be sent to a mercury reclaiming plant. It must not be discarded.
14.0
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I, Principles. EPA-600/9-76-005, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1976.
2. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods. EPA-600/4-77-027a, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1977.
3. Dasqupta, P. K., and K. B. DeCesare. Stability of Sulfur Dioxide in Formaldehyde and Its Anomalous Behavior in Tetrachloromercurate (II). Submitted for publication in
4. West, P. W., and G. C. Gaeke. Fixation of Sulfur Dioxide as Disulfitomercurate (II) and Subsequent Colorimetric Estimation. Anal. Chem., 28:1816, 1956.
5. Ephraim, F. Inorganic Chemistry. P. C. L. Thorne and E. R. Roberts, Eds., 5th Edition, Interscience, 1948, p. 562.
6. Lyles, G. R., F. B. Dowling, and V. J. Blanchard. Quantitative Determination of Formaldehyde in the Parts Per Hundred Million Concentration Level. J. Air. Poll. Cont. Assoc., Vol. 15(106), 1965.
7. McKee, H. C., R. E. Childers, and O. Saenz, Jr. Collaborative Study of Reference Method for Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method). EPA-APTD-0903, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, September 1971.
8. Urone, P., J. B. Evans, and C. M. Noyes. Tracer Techniques in Sulfur—Air Pollution Studies Apparatus and Studies of Sulfur Dioxide Colorimetric and Conductometric Methods. Anal. Chem., 37: 1104, 1965.
9. Bostrom, C. E. The Absorption of Sulfur Dioxide at Low Concentrations (pphm) Studied by an Isotopic Tracer Method. Intern. J. Air Water Poll., 9:333, 1965.
10. Scaringelli, F. P., B. E. Saltzman, and S. A. Frey. Spectrophotometric Determination of Atmospheric Sulfur Dioxide. Anal. Chem., 39: 1709, 1967.
11. Pate, J. B., B. E. Ammons, G. A. Swanson, and J. P. Lodge, Jr. Nitrite Interference in Spectrophotometric Determination of Atmospheric Sulfur Dioxide. Anal. Chem., 37:942, 1965.
12. Zurlo, N., and A. M. Griffini. Measurement of the Sulfur Dioxide Content of the Air in the Presence of Oxides of Nitrogen and Heavy Metals. Medicina Lavoro, 53:330, 1962.
13. Rehme, K. A., and F. P. Scaringelli. Effect of Ammonia on the Spectrophotometric Determination of Atmospheric Concentrations of Sulfur Dioxide. Anal. Chem., 47:2474, 1975.
14. McCoy, R. A., D. E. Camann, and H. C. McKee. Collaborative Study of Reference Method for Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method) (24-Hour Sampling). EPA-650/4-74-027, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, December 1973.
15. Fuerst, R. G. Improved Temperature Stability of Sulfur Dioxide Samples Collected by the Federal Reference Method. EPA-600/4-78-018, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, April 1978.
16. Scaringelli, F. P., L. Elfers, D. Norris, and S. Hochheiser. Enhanced Stability of Sulfur Dioxide in Solution. Anal. Chem., 42:1818, 1970.
17. Martin, B. E. Sulfur Dioxide Bubbler Temperature Study. EPA-600/4-77-040, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, August 1977.
18. American Society for Testing and Materials. ASTM Standards, Water; Atmospheric Analysis. Part 23. Philadelphia, PA, October 1968, p. 226.
19. O'Keeffe, A. E., and G. C. Ortman. Primary Standards for Trace Gas Analysis. Anal. Chem., 38:760, 1966.
20. Scaringelli, F. P., S. A. Frey, and B. E. Saltzman. Evaluation of Teflon Permeation Tubes for Use with Sulfur Dioxide. Amer. Ind. Hygiene Assoc. J., 28:260, 1967.
21. Scaringelli, F. P., A. E. O'Keeffe, E. Rosenberg, and J. P. Bell, Preparation of Known Concentrations of Gases and Vapors With Permeation Devices Calibrated Gravimetrically. Anal. Chem., 42:871, 1970.
22. A Procedure for Establishing Traceability of Gas Mixtures to Certain National Bureau of Standards Standard Reference Materials. EPA-600/7-81-010, U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory (MD-77), Research Triangle Park, NC 27711, January 1981.
1.0
1.1 This method provides a measurement of the mass concentration of total suspended particulate matter (TSP) in ambient air for determining compliance with the primary and secondary national ambient air quality standards for particulate matter as specified in § 50.6 and § 50.7 of this chapter. The measurement process is nondestructive, and the size of the sample collected is usually adequate for subsequent chemical analysis. Quality assurance procedures and guidance are provided in part 58, appendixes A and B, of this chapter and in References 1 and 2.
2.0
2.1 An air sampler, properly located at the measurement site, draws a measured quantity of ambient air into a covered housing and through a filter during a 24-hr (nominal) sampling period. The sampler flow rate and the geometry of the shelter favor the collection of particles up to 25-50
2.2 The filter is weighed (after moisture equilibration) before and after use to determine the net weight (mass) gain. The total volume of air sampled, corrected to EPA standard conditions (25 °C, 760 mm Hg [101 kPa]), is determined from the measured flow rate and the sampling time. The concentration of total suspended particulate matter in the ambient air is computed as the mass of collected particles divided by the volume of air sampled, corrected to standard conditions, and is expressed in micrograms per standard cubic meter (
3.0
3.1 The approximate concentration range of the method is 2 to 750
3.2 At wind speeds between 1.3 and 4.5 m/sec (3 and 10 mph), the high-volume air sampler has been found to collect particles up to 25 to 50
4.0
4.1 Based upon collaborative testing, the relative standard deviation (coefficient of variation) for single analyst precision (repeatability) of the method is 3.0 percent. The corresponding value for interlaboratory precision (reproducibility) is 3.7 percent.(
5.0
5.1 The absolute accuracy of the method is undefined because of the complex nature of atmospheric particulate matter and the difficulty in determining the “true” particulate matter concentration. This method provides a measure of particulate matter concentration suitable for the purpose specified under Section 1.0, Applicability.
6.0
6.1
*At elevated altitudes, the effectiveness of automatic flow controllers may be reduced because of a reduction in the maximum sampler flow.
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
7.0
(See References 1 and 2 for quality assurance information.)
Samplers purchased prior to the effective date of this amendment are not subject to specifications preceded by (
7.1
7.1.1
7.1.2
7.1.3.
7.1.4
7.1.5
7.1.6
7.1.7
7.1.8
7.1.9
7.1.10
7.2
7.2.1 The sampler shall have suitable means to:
a. Hold and seal the filter to the sampler housing.
b. Allow the filter to be changed conveniently.
c. Preclude leaks that would cause error in the measurement of the air volume passing through the filter.
d. (
(
7.2.2
7.2.3
7.2.4
7.3
7.3.1 The sampler shelter shall:
a. Maintain the filter in a horizontal position at least 1 m above the sampler supporting surface so that sample air is drawn downward through the filter.
b. Be rectangular in shape with a gabled roof, similar to the design shown in Figure 1.
c. Cover and protect the filter and sampler from precipitation and other weather.
d. Discharge exhaust air at least 40 cm from the sample air inlet.
e. Be designed to minimize the collection of dust from the supporting surface by incorporating a baffle between the exhaust outlet and the supporting surface.
7.3.2 The sampler cover or roof shall overhang the sampler housing somewhat, as shown in Figure 1, and shall be mounted so as to form an air inlet gap between the cover and the sampler housing walls.
7.4
7.4.1 The sampler shall incorporate a flow rate measurement device capable of indicating the total sampler flow rate. Two common types of flow indicators covered in the calibration procedure are (1) an electronic mass flowmeter and (2) an orifice or orifices
7.4.2
7.5
7.5.1
7.5.2
7.6
7.6.1
7.6.2
7.7
7.7.1 The timing device must be capable of starting and stopping the sampler to obtain an elapsed run-time of 24 hr
7.7.2
7.8
7.8.1
7.8.2
7.8.3
7.8.4
7.8.5 The flow rate transfer standard must connect without leaks to the inlet of the sampler and measure the flow rate of the total air sample.
7.8.6 The flow rate transfer standard must include a means to vary the sampler flow rate over the range of 1.0 to 1.8 m
7.8.7 The conventional type of flow transfer standard consists of: An orifice unit with adapter that connects to the inlet of the sampler, a manometer or other device to measure orifice pressure drop, a means to vary the flow through the sampler unit, a thermometer to measure the ambient temperature, and a barometer to measure ambient pressure. Two such devices are shown in Figures 2a and 2b. Figure 2a shows multiple fixed resistance plates, which necessitate disassembly of the unit each time the flow resistance is changed. A preferable design, illustrated in Figure 2b, has a variable flow restriction that can be adjusted externally without disassembly of the unit. Use of a conventional, orifice-type transfer standard is assumed in the calibration procedure (Section 9). However, the use of other types of transfer standards meeting the above specifications, such as the one shown in Figure 2c, may be approved; see the note following Section 9.1.
7.9
7.9.1
7.9.2
7.10
7.10.1
7.10.2 Weighing chamber designed to accept an unfolded 20.3 x 25.4 cm (8 x 10 in) filter.
7.11
7.12
8.0
(See References 1 and 2 for quality assurance information.)
8.1 Number each filter, if not already numbered, near its edge with a unique identification number.
8.2 Backlight each filter and inspect for pinholes, particles, and other imperfections; filters with visible imperfections must not be used.
8.3 Equilibrate each filter in the conditioning environment for at least 24-hr.
8.4 Following equilibration, weigh each filter to the nearest milligram and record this tare weight (W
8.5 Do not bend or fold the filter before collection of the sample.
8.6 Open the shelter and install a numbered, preweighed filter in the sampler, following the sampler manufacturer's instructions. During inclement weather, precautions must be taken while changing filters to prevent damage to the clean filter and loss of sample from or damage to the exposed filter. Filter cassettes that can be loaded and unloaded in the laboratory may be used to minimize this problem (See Section 6.6).
8.7 Close the shelter and run the sampler for at least 5 min to establish run-temperature conditions.
8.8 Record the flow indicator reading and, if needed, the barometric pressure (P
8.9 Record the sampler identification information (filter number, site location or identification number, sample date, and starting time).
8.10 Set the timer to start and stop the sampler such that the sampler runs 24-hrs, from midnight to midnight (local time).
8.11 As soon as practical following the sampling period, run the sampler for at least 5 min to again establish run-temperature conditions.
8.12 Record the flow indicator reading and, if needed, the barometric pressure (P
No onsite pressure or temperature measurements are necessary if the sampler flow indicator does not require pressure or temperature corrections (e.g., a mass flowmeter) or if average barometric pressure and seasonal average temperature for the site are incorporated into the sampler calibration (see step 9.3.9). For individual pressure and temperature corrections, the ambient pressure and temperature can be obtained by onsite measurements or from a nearby weather station. Barometric pressure readings obtained from airports must be station pressure, not corrected to sea level, and may need to be corrected for differences in elevation between the sampler site and the airport. For samplers having flow recorders but not constant flow controllers, the average temperature and pressure at the site
8.13 Stop the sampler and carefully remove the filter, following the sampler manufacturer's instructions. Touch only the outer edges of the filter. See the precautions in step 8.6.
8.14 Fold the filter in half lengthwise so that only surfaces with collected particulate matter are in contact and place it in the filter holder (glassine envelope or manila folder).
8.15 Record the ending time or elapsed time on the filter information record, either from the stop set-point time, from an elapsed time indicator, or from a continuous flow record. The sample period must be 1,440
8.16 Record on the filter information record any other factors, such as meteorological conditions, construction activity, fires or dust storms, etc., that might be pertinent to the measurement. If the sample is known to be defective, void it at this time.
8.17 Equilibrate the exposed filter in the conditioning environment for at least 24-hrs.
8.18 Immediately after equilibration, reweigh the filter to the nearest milligram and record the gross weight with the filter identification number. See Section 10 for TSP concentration calculations.
9.0
9.1 Calibration of the high volume sampler's flow indicating or control device is necessary to establish traceability of the field measurement to a primary standard via a flow rate transfer standard. Figure 3a illustrates the certification of the flow rate transfer standard and Figure 3b illustrates its use in calibrating a sampler flow indicator. Determination of the corrected flow rate from the sampler flow indicator, illustrated in Figure 3c, is addressed in Section 10.1
The following calibration procedure applies to a conventional orifice-type flow transfer standard and an orifice-type flow indicator in the sampler (the most common types). For samplers using a pressure recorder having a square-root scale, 3 other acceptable calibration procedures are provided in Reference 12. Other types of transfer standards may be used if the manufacturer or user provides an appropriately modified calibration procedure that has been approved by EPA under Section 2.8 of appendix C to part 58 of this chapter.
9.2
9.2.1
9.2.2 Connect the flow rate transfer standard to the inlet of the standard volume meter. Connect the manometer to measure the pressure at the inlet of the standard volume meter. Connect the orifice manometer to the pressure tap on the transfer standard. Connect a high-volume air pump (such as a high-volume sampler blower) to the outlet side of the standard volume meter. See Figure 3a.
9.2.3 Check for leaks by temporarily clamping both manometer lines (to avoid fluid loss) and blocking the orifice with a large-diameter rubber stopper, wide cellophane tape, or other suitable means. Start the high-volume air pump and note any change in the standard volume meter reading. The reading should remain constant. If the reading changes, locate any leaks by listening for a whistling sound and/or retightening all connections, making sure that all gaskets are properly installed.
9.2.4 After satisfactorily completing the leak check as described above, unclamp both manometer lines and zero both manometers.
9.2.5 Achieve the appropriate flow rate through the system, either by means of the variable flow resistance in the transfer standard or by varying the voltage to the air pump. (Use of resistance plates as shown in Figure 1a is discouraged because the above leak check must be repeated each time a new resistance plate is installed.) At least five different but constant flow rates, evenly distributed, with at least three in the specified
9.2.6 Measure and record the certification data on a form similar to the one illustrated in Figure 4 according to the following steps.
9.2.7 Observe the barometric pressure and record as P
9.2.8 Read the ambient temperature in the vicinity of the standard volume meter and record it as T
9.2.9 Start the blower motor, adjust the flow, and allow the system to run for at least 1 min for a constant motor speed to be attained.
9.2.10 Observe the standard volume meter reading and simultaneously start a stopwatch. Record the initial meter reading (V
9.2.11 Maintain this constant flow rate until at least 3 m
9.2.12 After at least 3 m
9.2.13 Calculate the volume measured by the standard volume meter at meter conditions of temperature and pressures as V
9.2.14 Correct this volume to standard volume (std m
Record Q
9.2.15 Repeat steps 9.2.9 through 9.2.14 for at least four additional constant flow rates, evenly spaced over the approximate range of 1.0 to 1.8 std m
9.2.16 For each flow, compute
9.2.17 Recalibrate the transfer standard annually or as required by applicable quality control procedures. (See Reference 2.)
9.3
For samplers equipped with a flow controlling device, the flow controller must be disabled to allow flow changes during calibration of the sampler's flow indicator, or the alternate calibration of the flow controller given in 9.4 may be used. For samplers using an orifice-type flow indicator downstream of the motor, do not vary the flow rate by adjusting the voltage or power supplied to the sampler.
9.3.1 A form similar to the one illustrated in Figure 5 should be used to record the calibration data.
9.3.2 Connect the transfer standard to the inlet of the sampler. Connect the orifice manometer to the orifice pressure tap, as illustrated in Figure 3b. Make sure there are no leaks between the orifice unit and the sampler.
9.3.3 Operate the sampler for at least 5 minutes to establish thermal equilibrium prior to the calibration.
9.3.4 Measure and record the ambient temperature, T
9.3.5 Adjust the variable resistance or, if applicable, insert the appropriate resistance plate (or no plate) to achieve the desired flow rate.
9.3.6 Let the sampler run for at least 2 min to re-establish the run-temperature conditions. Read and record the pressure drop across the orifice (
9.3.7 Calculate
9.3.8 Repeat steps 9.3.5, 9.3.6, and 9.3.7 for several additional flow rates distributed over a range that includes 1.1 to 1.7 std m
9.3.9 Determine the calibration curve by plotting values of the appropriate expression involving I, selected from table 1, against Q
9.3.10 Draw the sampler calibration curve or calculate the linear least squares slope (m), intercept (b), and correlation coefficient of the calibration curve: [Expression from table 1]= mQ
9.3.11 For a sampler equipped with a flow controller, the flow controlling mechanism should be re-enabled and set to a flow near the lower flow limit to allow maximum control range. The sample flow rate should be verified at this time with a clean filter installed. Then add two or more filters to the sampler to see if the flow controller maintains a constant flow; this is particularly important at high altitudes where the range of the flow controller may be reduced.
9.4 Alternate calibration of flow-controlled samplers. A flow-controlled sampler may be calibrated solely at its controlled flow rate, provided that previous operating history of the sampler demonstrates that the flow rate is stable and reliable. In this case, the flow indicator may remain uncalibrated but should be used to indicate any relative change between initial and final flows, and the sampler should be recalibrated more often to minimize potential loss of samples because of controller malfunction.
9.4.1 Set the flow controller for a flow near the lower limit of the flow range to allow maximum control range.
9.4.2 Install a clean filter in the sampler and carry out steps 9.3.2, 9.3.3, 9.3.4, 9.3.6, and 9.3.7.
9.4.3 Following calibration, add one or two additional clean filters to the sampler, reconnect the transfer standard, and operate the sampler to verify that the controller maintains the same calibrated flow rate; this is particularly important at high altitudes where the flow control range may be reduced.
10.0
10.1 Determine the average sampler flow rate during the sampling period according to either 10.1.1 or 10.1.2 below.
10.1.1 For a sampler without a continuous flow recorder, determine the appropriate expression to be used from table 2 corresponding to the one from table 1 used in step 9.3.9. Using this appropriate expression, determine Q
10.1.2 For a sampler with a continuous flow recorder, determine the average flow rate device reading, I, for the period. Determine the appropriate expression from table 2 corresponding to the one from table 1 used in step 9.3.9. Then using this expression and the average flow rate reading, determine Q
If the trace shows substantial flow change during the sampling period, greater accuracy may be achieved by dividing the sampling period into intervals and calculating an average reading before determining Q
10.2 Calculate the total air volume sampled as:
10.3 Calculate and report the particulate matter concentration as:
10.4 If desired, the actual particulate matter concentration (see Section 2.2) can be calculated as follows:
11.0
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I, Principles. EPA-600/9-76-005, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1976.
2. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods. EPA-600/4-77-027a, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1977.
3. Wedding, J. B., A. R. McFarland, and J. E. Cernak. Large Particle Collection Characteristics of Ambient Aerosol Samplers. Environ. Sci. Technol.
4. McKee, H. C., et al. Collaborative Testing of Methods to Measure Air Pollutants, I. The High-Volume Method for Suspended Particulate Matter. J. Air Poll. Cont. Assoc., 22 (342), 1972.
5. Clement, R. E., and F. W. Karasek. Sample Composition Changes in Sampling and Analysis of Organic Compounds in Aerosols. The Intern. J. Environ. Anal. Chem., 7:109, 1979.
6. Lee, R. E., Jr., and J. Wagman. A Sampling Anomaly in the Determination of Atmospheric Sulfuric Concentration. Am. Ind. Hygiene Assoc. J., 27:266, 1966.
7. Appel, B. R., et al. Interference Effects in Sampling Particulate Nitrate in Ambient Air. Atmospheric Environment, 13:319, 1979.
8. Tierney, G. P., and W. D. Conner. Hygroscopic Effects on Weight Determinations of Particulates Collected on Glass-Fiber Filters. Am. Ind. Hygiene Assoc. J., 28:363, 1967.
9. Chahal, H. S., and D. J. Romano. High-Volume Sampling Effect of Windborne Particulate Matter Deposited During Idle Periods. J. Air Poll. Cont. Assoc., Vol. 26 (885), 1976.
10. Patterson, R. K. Aerosol Contamination from High-Volume Sampler Exhaust. J. Air Poll. Cont. Assoc., Vol. 30 (169), 1980.
11. EPA Test Procedures for Determining pH and Integrity of High-Volume Air Filters. QAD/M-80.01. Available from the Methods Standardization Branch, Quality Assurance Division, Environmental Monitoring Systems Laboratory (MD-77), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1980.
12. Smith, F., P. S. Wohlschlegel, R. S. C. Rogers, and D. J. Mulligan. Investigation of Flow Rate Calibration Procedures Associated with the High-Volume Method for Determination of Suspended Particulates. EPA-600/4-78-047, U.S. Environmental Protection Agency, Research Triangle Park, NC, June 1978.
1. Measurements are based on the absorption of infrared radiation by carbon monoxide (CO) in a non-dispersive photometer. Infrared energy from a source is passed through a cell containing the gas sample to be analyzed, and the quantitative absorption of energy by CO in the sample cell is measured by a suitable detector. The photometer is sensitized to CO by employing CO gas in either the detector or in a filter cell in the optical path, thereby limiting the measured absorption to one or more of the characteristic wavelengths at which CO strongly absorbs. Optical filters or other means may
2. An analyzer based on this principle will be considered a reference method only if it has been designated as a reference method in accordance with part 53 of this chapter.
3. Sampling considerations.
The use of a particle filter on the sample inlet line of an NDIR CO analyzer is optional and left to the discretion of the user or the manufacturer. Use of filter should depend on the analyzer's susceptibility to interference, malfunction, or damage due to particles.
1.
(1) One method uses a single certified standard cylinder of CO, diluted as necessary with zero air, to obtain the various calibration concentrations needed.
(2) The other method uses individual certified standard cylinders of CO for each concentration needed. Additional information on calibration may be found in Section 2.0.9 of Reference 1.
2.
2.1 Flow controller(s). Device capable of adjusting and regulating flow rates. Flow rates for the dilution method (Figure 1) must be regulated to
2.2 Flow meter(s). Calibrated flow meter capable of measuring and monitoring flow rates. Flow rates for the dilution method (Figure 1) must be measured with an accuracy of
2.3 Pressure regulator(s) for standard CO cylinder(s). Regulator must have nonreactive diaphragm and internal parts and a suitable delivery pressure.
2.4 Mixing chamber. A chamber designed to provide thorough mixing of CO and diluent air for the dilution method.
2.5 Output manifold. The output manifold should be of sufficient diameter to insure an insignificant pressure drop at the analyzer connection. The system must have a vent designed to insure atmospheric pressure at the manifold and to prevent ambient air from entering the manifold.
3.
3.1 CO concentration standard(s). Cylinder(s) of CO in air containing appropriate concentrations(s) of CO suitable for the selected operating range of the analyzer under calibration; CO standards for the dilution method may be contained in a nitrogen matrix if the zero air dilution ratio is not less than 100:1. The assay of the cylinder(s) must be traceable either to a National Bureau of Standards (NBS) CO in air Standard Reference Material (SRM) or to an NBS/EPA-approved commercially available Certified Reference Material (CRM). CRM's are described in Reference 2, and a list of CRM sources is available from the address shown for Reference 2. A recommended protocol for certifying CO gas cylinders against either a CO SRM or a CRM is given in Reference 1. CO gas cylinders should be recertified on a regular basis as determined by the local quality control program.
3.2 Dilution gas (zero air). Air, free of contaminants which will cause a detectable response on the CO analyzer. The zero air should contain
4.
4.1 Assemble a dynamic calibration system such as the one shown in Figure 1. All calibration gases including zero air must be introduced into the sample inlet of the analyzer system. For specific operating instructions refer to the manufacturer's manual.
4.2 Insure that all flowmeters are properly calibrated, under the conditions of use, if appropriate, against an authoritative standard such as a soap-bubble meter or wet-test meter. All volumetric flowrates should be corrected to 25 °C and 760 mm Hg (101 kPa). A discussion on calibration of flowmeters is given in Reference 1.
4.3 Select the operating range of the CO analyzer to be calibrated.
4.4 Connect the signal output of the CO analyzer to the input of the strip chart recorder or other data collection device. All adjustments to the analyzer should be based on the appropriate strip chart or data device readings. References to analyzer responses in the procedure given below refer to recorder or data device responses.
4.5 Adjust the calibration system to deliver zero air to the output manifold. The total air flow must exceed the total demand of the analyzer(s) connected to the output manifold to insure that no ambient air is pulled into the manifold vent. Allow the analyzer to sample zero air until a stable respose is obtained. After the response has stabilized, adjust the analyzer zero control. Offsetting the analyzer zero adjustments to +5 percent of scale is recommended to facilitate observing negative zero drift. Record the stable zero air response as Z
4.6 Adjust the zero air flow and the CO flow from the standard CO cylinder to provide a diluted CO concentration of approximately 80 percent of the upper range limit (URL) of the operating range of the analyzer. The total air flow must exceed the total demand of the analyzer(s) connected to the output manifold to insure that no ambient air is
Sample this CO concentration until a stable response is obtained. Adjust the analyzer span control to obtain a recorder response as indicated below:
If substantial adjustment of the analyzer span control is required, it may be necessary to recheck the zero and span adjustments by repeating Steps 4.5 and 4.6. Record the CO concentration and the analyzer's response. 4.7 Generate several additional concentrations (at least three evenly spaced points across the remaining scale are suggested to verify linearity) by decreasing F
5.
5.1 Use a multi-cylinder system such as the typical one shown in Figure 2.
5.2 The flowmeter need not be accurately calibrated, provided the flow in the output manifold exceeds the analyzer's flow demand.
5.3 The various CO calibration concentrations required in Steps 4.6 and 4.7 are obtained without dilution by selecting the appropriate certified standard cylinder.
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II—Ambient Air Specific Methods, EPA-600/4-77-027a, U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory, Research Triangle Park, NC 27711, 1977.
2. A procedure for Establishing Traceability of Gas Mixtures to Certain National Bureau of Standards Standard Reference Materials. EPA-600/7-81-010, U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory (MD-77), Research Triangle Park, NC 27711, January 1981.
1. Ambient air and ethylene are delivered simultaneously to a mixing zone where the ozone in the air reacts with the ethylene to emit light, which is detected by a photomultiplier tube. The resulting photocurrent is amplified and is either read directly or displayed on a recorder.
2. An analyzer based on this principle will be considered a reference method only if it has been designated as a reference method in accordance with part 53 of this chapter and calibrated as follows:
1.
In practice, a stable O
2.
3.
3.1
3.2
3.3
3.4
3.5
3.6
3.7
4.
4.1
5.
5.1
5.2
5.2.1
5.2.2
5.2.3
The linearity error must be less than 5%. Since the accuracy of the measured flow-rates will affect the linearity error as measured this way, the test is not necessarily conclusive. Additional information on verifying linearity is contained in Reference 9.
5.2.4
5.2.5
5.3
5.3.1 Allow the photometer system to warm up and stabilizer.
5.3.2 Verify that the flowrate through the photometer absorption cell, F allows the cell to be flushed in a reasonably short period of time (2 liter/min is a typical flow). The precision of the measurements is inversely related to the time required for flushing, since the photometer drift error increases with time.
5.3.3 Insure that the flowrate into the output manifold is at least 1 liter/min greater than the total flowrate required by the photometer and any other flow demand connected to the manifold.
5.3.4 Insure that the flowrate of zero air, F
5.3.5 With zero air flowing in the output manifold, actuate the two-way valve to allow the photometer to sample first the manifold zero air, then F
In some commercially available photometers, the operation of the two-way valve and various other operations in section 5.3 may be carried out automatically by the photometer.
5.3.6 Adjust the O
5.3.7 Actuate the two-way valve to allow the photometer to sample zero air until the absorption cell is thoroughly flushed and record the stable measured value of I
5.3.8 Actuate the two-way valve to allow the photometer to sample the ozone concentration until the absorption cell is thoroughly flushed and record the stable measured value of I.
5.3.9 Record the temperature and pressure of the sample in the photometer absorption cell. (See Reference 9 for guidance.)
5.3.10 Calculate the O
Some commercial photometers may automatically evaluate all or part of equation 4. It is the operator's responsibility to verify that all of the information required for equation 4 is obtained, either automatically by the photometer or manually. For “automatic” photometers which evaluate the first term of equation 4 based on a linear approximation, a manual correction may be required, particularly at higher O
5.3.11 Obtain additional O
5.4
5.5
5.5.1 Allow sufficient time for the O
5.5.2 Allow the O
5.5.3 Generate an O
5.5.4 Adjust the O
recorder response (%scale) =
Record the O
5.5.5 Generate several other O
5.5.6 Plot the O
5.5.7
1. E.C.Y. Inn and Y. Tanaka, “Absorption coefficient of Ozone in the Ultraviolet and Visible Regions”,
2. A. G. Hearn, “Absorption of Ozone in the Ultraviolet and Visible Regions of the Spectrum”,
3. W. B. DeMore and O. Raper, “Hartley Band Extinction Coefficients of Ozone in the Gas Phase and in Liquid Nitrogen, Carbon Monoxide, and Argon”,
4. M. Griggs, “Absorption Coefficients of Ozone in the Ultraviolet and Visible Regions”,
5. K. H. Becker, U. Schurath, and H. Seitz, “Ozone Olefin Reactions in the Gas Phase. 1. Rate Constants and Activation Energies”,
6. M. A. A. Clyne and J. A. Coxom, “Kinetic Studies of Oxy-halogen Radical Systems”,
7. J. W. Simons, R. J. Paur, H. A. Webster, and E. J. Bair, “Ozone Ultraviolet Photolysis. VI. The Ultraviolet Spectrum”,
8. Transfer Standards for Calibration of Ambient Air Monitoring Analyzers for Ozone, EPA publication number EPA-600/4-79-056, EPA, National Exposure Research Laboratory, Department E, (MD-77B), Research Triangle Park, NC 27711.
9. Technical Assistance Document for the Calibration of Ambient Ozone Monitors, EPA publication number EPA-600/4-79-057, EPA, National Exposure Research Laboratory, Department E, (MD-77B), Research Triangle Park, NC 27711.
1. Atmospheric concentrations of nitrogen dioxide (NO
2.
2.1 Chemiluminescence NO/NO
2.2 The use of integrating flasks on the sample inlet line of chemiluminescence NO/NO
2.3 The use of particulate filters on the sample inlet line of chemiluminescence NO/NO
3. An analyzer based on this principle will be considered a reference method only if it has been designated as a reference method in accordance with part 53 of this chapter.
1.
1.1
1.2
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
1.2.8
1.2.9
1.2.10
1.3
1.3.1
1.3.2
1.4
1.4.1 The O
1.4.2 The flow conditions to be used in the GPT system are determined by the following procedure:
(a) Determine
(b) Establish [NO]
(c) Determine F
(d) Select a convenient or available reaction chamber volume. Initially, a trial
(e) Compute FO as
(f) Compute
(g) Compute the diluent air flowrate as
(h) If
A dynamic parameter lower than 2.75 ppm-minutes may be used if it can be determined empirically that quantitative reaction of O
1.5
1.5.1 Assemble a dynamic calibration system such as the one shown in Figure 1.
1.5.2 Insure that all flowmeters are calibrated under the conditions of use against a reliable standard such as a soap-bubble meter or wet-test meter. All volumetric flowrates should be corrected to 25 °C and 760 mm Hg. A discussion on the calibration of flowmeters is given in reference 13.
1.5.3 Precautions must be taken to remove O
1.5.4 Select the operating range of the NO/NO
Some analyzer designs may require identical ranges for NO, NO
1.5.5 Connect the recorder output cable(s) of the NO/NO
1.5.6 Determine the GPT flow conditions required to meet the dynamic parameter specification as indicated in 1.4.
1.5.7 Adjust the diluent air and O
Some analyzers may have separate zero controls for NO, NO
Offsetting the analyzer zero adjustments to +5 percent of scale is recommended to facilitate observing negative zero drift. Record the stable zero air responses as Z
1.5.8
1.5.8.1
Some analyzers may have separate span controls for NO, NO
1.5.8.2
If the analyzer has only one span control, the span adjustment is made on the NO channel and no further adjustment is made here for NO
1.5.8.3 Generate several additional concentrations (at least five evenly spaced points across the remaining scale are suggested to verify linearity) by decreasing F
1.5.9
1.5.9.1 Assuming the NO
1.5.9.2 Adjust the O
1.5.9.3 Calculate the resulting NO
If the analyzer has only one or two span controls, the span adjustments are made on the NO channel or NO and NO
1.5.9.4 Maintaining the same F
1.5.10
1.5.10.1 For each NO
Supplemental information on calibration and other procedures in this method are given in reference 13.
2.
Stable O
Chemiluminescence NO/NO
NO concentration standard.
NO
2.1
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
2.2.8
2.2.9
The valves should be constructed of glass, Teflon
2.2.10
2.2.11
2.3
2.3.1
2.3.1.1
2.3.1.2
2.3.3
2.4
2.4.1 Assemble the calibration apparatus such as the typical one shown in Figure 2.
2.4.2 Insure that all flowmeters are calibrated under the conditions of use against a reliable standard such as a soap bubble meter or wet-test meter. All volumetric flowrates should be corrected to 25 °C and 760 mm Hg. A discussion on the calibration of flowmeters is given in reference 13.
2.4.3 Install the permeation device in the constant temperature chamber. Provide a small fixed air flow (200-400 scm
2.4.4 Precautions must be taken to remove O
(1) Carefully evacuating the regulator, when possible, after the regulator has been connected to the cylinder and before opening the cylinder valve;
(2) Thoroughly flushing the regulator and delivery system with NO after opening the cylinder valve;
(3) Not removing the regulator from the cylinder between calibrations unless absolutely necessary. Further discussion of these procedures is given in reference 13.
2.4.5 Select the operating range of the NO/NO
Some analyzer designs may require identical ranges for NO, NO
2.4.6 Connect the recorder output cable(s) of the NO/NO
2.4.7 Switch the valve to vent the flow from the permeation device and adjust the diluent air flowrate, F
Some analyzers may have separate zero controls for NO, NO
2.4.8
2.4.8.1
Some analyzers may have separate span controls for NO, NO
2.4.8.2
If the analyzer has only one span control, the span adjustment is made on the NO channel and no further adjustment is made here for NO
2.4.8.3 Generate several additional concentrations (at least five evenly spaced points across the remaining scale are suggested to verify linearity) by decreasing F
2.4.9
2.4.9.1 Remove the NO flow. Assuming the NO
2.4.9.2 Adjust
If the analyzer has only one or two span controls, the span adjustments are made on the NO channel or NO and NO
2.4.9.3 Adjust
2.4.10
2.4.10.1 Plot [NO
Supplemental information on calibration and other procedures in this method are given in reference 13.
3.
1. A. Fontijn, A. J. Sabadell, and R. J. Ronco, “Homogeneous Chemiluminescent Measurement of Nitric Oxide with Ozone,” Anal. Chem., 42, 575 (1970).
2. D. H. Stedman, E. E. Daby, F. Stuhl, and H. Niki, “Analysis of Ozone and Nitric Oxide by a Chemiluminiscent Method in Laboratory and Atmospheric Studies of Photochemical Smog,” J. Air Poll. Control Assoc., 22, 260 (1972).
3. B. E. Martin, J. A. Hodgeson, and R. K. Stevens, “Detection of Nitric Oxide Chemiluminescence at Atmospheric Pressure,” Presented at 164th National ACS Meeting, New York City, August 1972.
4. J. A. Hodgeson, K. A. Rehme, B. E. Martin, and R. K. Stevens, “Measurements for Atmospheric Oxides of Nitrogen and Ammonia by Chemiluminescence,” Presented at 1972 APCA Meeting, Miami, FL, June 1972.
5. R. K. Stevens and J. A. Hodgeson, “Applications of Chemiluminescence Reactions to the Measurement of Air Pollutants,” Anal. Chem., 45, 443A (1973).
6. L. P. Breitenbach and M. Shelef, “Development of a Method for the Analysis of NO
7. A. M. Winer, J. W. Peters, J. P. Smith, and J. N. Pitts, Jr., “Response of Commercial Chemiluminescent NO-NO
8. K. A. Rehme, B. E. Martin, and J. A. Hodgeson, Tentative Method for the Calibration of Nitric Oxide, Nitrogen Dioxide, and Ozone Analyzers by Gas Phase Titration,” EPA-R2-73-246, March 1974.
9. J. A. Hodgeson, R. K. Stevens, and B. E. Martin, “A Stable Ozone Source Applicable as a Secondary Standard for Calibration of Atmospheric Monitors,” ISA Transactions, 11, 161 (1972).
10. A. E. O'Keeffe and G. C. Ortman, “Primary Standards for Trace Gas Analysis,” Anal. Chem., 38, 760 (1966).
11. F. P. Scaringelli, A. E. O'Keeffe, E. Rosenberg, and J. P. Bell, “Preparation of Known Concentrations of Gases and Vapors with Permeation Devices Calibrated Gravimetrically,” Anal. Chem., 42, 871 (1970).
12. H. L. Rook, E. E. Hughes, R. S. Fuerst, and J. H. Margeson, “Operation Characteristics of NO
13. E. C. Ellis, “Technical Assistance Document for the Chemiluminescence Measurement of Nitrogen Dioxide,” EPA-E600/4-75-003 (Available in draft form from the United States Environmental Protection Agency,
14. A Procedure for Establishing Traceability of Gas Mixtures to Certain National Bureau of Standards Standard Reference Materials. EPA-600/7-81-010, Joint publication by NBS and EPA. Available from the U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory (MD-77), Research Triangle Park, NC 27711, May 1981.
15.
1.
1.1 Ambient air suspended particulate matter is collected on a glass-fiber filter for 24 hours using a high volume air sampler. The analysis of the 24-hour samples may be performed for either individual samples or composites of the samples collected over a calendar month or quarter, provided that the compositing procedure has been approved in accordance with section 2.8 of appendix C to part 58 of this chapter—
1.2 Lead in the particulate matter is solubilized by extraction with nitric acid (HNO
1.3 The lead content of the sample is analyzed by atomic absorption spectrometry using an air-acetylene flame, the 283.3 or 217.0 nm lead absorption line, and the optimum instrumental conditions recommended by the manufacturer.
1.4 The ultrasonication extraction with HNO
2.
2.1
2.2
2.3
3.
3.1
3.2
Light scattering interferences can, however, be corrected for instrumentally. Since the dissolved solids can vary depending on the origin of the sample, the correction may be necessary, especially when using the 217.0 nm line. Dual beam instruments with a continuum source give the most accurate correction. A less accurate correction can be obtained by using a nonabsorbing lead line that is near the lead analytical line. Information on use of these correction techniques can be obtained from instrument manufacturers' manuals.
If instrumental correction is not feasible, the interference can be eliminated by use of the ammonium pyrrolidinecarbodithioate-methylisobutyl ketone, chelation-solvent extraction technique of sample preparation.(
4.
4.1 The high-volume sampling procedure used to collect ambient air particulate matter has a between-laboratory relative standard deviation of 3.7 percent over the range 80 to 125
4.2 Single laboratory experiments and collaborative testing indicate that there is no significant difference in lead recovery between the hot and ultrasonic extraction procedures.(
5.
5.1
5.1.1
5.2
5.2.1
5.2.1.1
5.2.1.2
5.2.2
5.2.2.1
5.2.2.2
5.2.2.3
5.2.2.4
5.2.3
5.2.4.
5.2.5
5.2.6
5.2.7
5.2.8
5.2.9 Parafilm “M”.
6.
6.1
6.1.1
6.1.1.1
It is important that the variation in lead content from filter to filter, within a given batch, be small.
6.1.1.2
6.1.1.2.1 For large batches of filters (>500 filters) select at random 20 to 30 filters from a given batch. For small batches (>500 filters) a lesser number of filters may be taken. Cut one
6.1.1.2.2 Calculate the total lead in each filter as
6.1.1.2.3 Calculate the mean, F
6.1.1.2.4 For acceptable batches, use the value of F
6.2
6.2.1 Concentrated (15.6
6.2.2 Concentrated (11.7
6.2.3
6.2.4 3
6.2.5 0.45
6.2.6 2.6
6.2.7 0.40
6.2.8 Lead nitrate, Pb(NO
6.3
6.3.1 Master standard, 1000
6.3.2 Master standard, 1000
Store standards in a polyethylene bottle. Commercially available certified lead standard solutions may also be used.
7.
7.1
7.2
7.2.1
7.2.1.1 Cut a
Lead in ambient particulate matter collected on glass fiber filters has been shown to be uniformly distributed across the filter.
7.2.1.2 Fold the strip in half twice and place in a 150-ml beaker. Add 15 ml of 3
7.2.1.3 Place beaker on the hot-plate, contained in a fume hood, and boil gently for 30 min. Do not let the sample evaporate to dryness.
7.2.1.4 Remove beaker from hot plate and cool to near room temperature.
7.2.1.5 Quantitatively transfer the sample as follows:
7.2.1.5.1 Rinse watch glass and sides of beaker with D.I. water.
7.2.1.5.2 Decant extract and rinsings into a 100-ml volumetric flask.
7.2.1.5.3 Add D.I. water to 40 ml mark on beaker, cover with watch glass, and set aside for a minimum of 30 minutes. This is a critical step and cannot be omitted since it allows the HNO
7.2.1.5.4 Decant the water from the filter into the volumetric flask.
7.2.1.5.5 Rinse filter and beaker twice with D.I. water and add rinsings to volumetric flask until total volume is 80 to 85 ml.
7.2.1.5.6 Stopper flask and shake vigorously. Set aside for approximately 5 minutes or until foam has dissipated.
7.2.1.5.7 Bring solution to volume with D.I. water. Mix thoroughly.
7.2.1.5.8 Allow solution to settle for one hour before proceeding with analysis.
7.2.1.5.9 If sample is to be stored for subsequent analysis, transfer to a linear polyethylene bottle.
7.2.2
7.2.2.1 Cut a
7.2.2.2 Fold the strip in half twice and place in a 30 ml beaker. Add 15 ml of the HNO
The parafilm should be placed over the beaker such that none of the parafilm is in contact with water in the ultrasonic bath. Otherwise, rinsing of the parafilm (section 7.2.2.4.1) may contaminate the sample.
7.2.2.3 Place the beaker in the ultrasonication bath and operate for 30 minutes.
7.2.2.4 Quantitatively transfer the sample as follows:
7.2.2.4.1 Rinse parafilm and sides of beaker with D.I. water.
7.2.2.4.2 Decant extract and rinsings into a 100 ml volumetric flask.
7.2.2.4.3 Add 20 ml D.I. water to cover the filter strip, cover with parafilm, and set aside for a minimum of 30 minutes. This is a critical step and cannot be omitted. The sample is then processed as in sections 7.2.1.5.4 through 7.2.1.5.9.
Samples prepared by the hot extraction procedure are now in 0.45
8.
8.1 Set the wavelength of the monochromator at 283.3 or 217.0 nm. Set or align other instrumental operating conditions as recommended by the manufacturer.
8.2 The sample can be analyzed directly from the volumetric flask, or an appropriate amount of sample decanted into a sample analysis tube. In either case, care should be taken not to disturb the settled solids.
8.3 Aspirate samples, calibration standards and blanks (section 9.2) into the flame and record the equilibrium absorbance.
8.4 Determine the lead concentration in
8.5 Samples that exceed the linear calibration range should be diluted with acid of the same concentration as the calibration standards and reanalyzed.
9.
9.1
9.2
9.3
To determine stability of the calibration curve, remeasure—alternately—one of the following calibration standards for every 10th sample analyzed: Concentration
10.
10.1
10.2
11.
To minimize the possibility of generating unreliable data, the user should follow practices established for assuring the quality of air pollution data, (
12.
1. During extraction of lead by the hot extraction procedure, it is important to keep the sample covered so that corrosion products—formed on fume hood surfaces which may contain lead—are not deposited in the extract.
2. The sample acid concentration should minimize corrosion of the nebulizer. However, different nebulizers may require lower acid concentrations. Lower concentrations can be used provided samples and standards have the same acid concentration.
3. Ashing of particulate samples has been found, by EPA and contractor laboratories, to be unnecessary in lead analyses by atomic absorption. Therefore, this step was omitted from the method.
4. Filtration of extracted samples, to remove particulate matter, was specifically excluded from sample preparation, because some analysts have observed losses of lead due to filtration.
5. If suspended solids should clog the nebulizer during analysis of samples, centrifuge the sample to remove the solids.
13.
(Secs. 109 and 301(a), Clean Air Act, as amended (42 U.S.C. 7409, 7601(a)))
14.
1. Scott, D. R. et al. “Atomic Absorption and Optical Emission Analysis of NASN Atmospheric Particulate Samples for Lead.”
2. Skogerboe, R. K. et al. “Monitoring for Lead in the Environment.” pp. 57-66, Department of Chemistry, Colorado State University, Fort Collins, CO 80523. Submitted to National Science Foundation for publications, 1976.
3. Zdrojewski, A. et al. “The Accurate Measurement of Lead in Airborne Particulates.”
4. Slavin, W., “Atomic Absorption Spectroscopy.” Published by Interscience Company, New York, NY (1968).
5. Kirkbright, G. F., and Sargent, M., “Atomic Absorption and Fluorescence Spectroscopy.” Published by Academic Press, New York, NY 1974.
6. Burnham, C. D. et al., “Determination of Lead in Airborne Particulates in Chicago and Cook County, IL, by Atomic Absorption Spectroscopy.” Envir. Sci. and Tech., 3,
7. “Proposed Recommended Practices for Atomic Absorption Spectrometry.”
8. Koirttyohann, S. R. and Wen, J. W., “Critical Study of the APCD-MIBK Extraction System for Atomic Absorption.”
9.
10. [Reserved]
11. Dubois, L., et al., “The Metal Content of Urban Air.” JAPCA,
12. EPA Report No. 600/4-77-034, June 1977, “Los Angeles Catalyst Study Symposium.” Page 223.
13.
14. Thompson, R. J. et al., “Analysis of Selected Elements in Atmospheric Particulate Matter by Atomic Absorption.”
15. To be published. EPA, QAB, EMSL, RTP, N.C. 27711
16.
This appendix explains how to determine when the expected number of days per calendar year with maximum hourly average concentrations above 0.12 ppm (235
The basic principle in making this determination is relatively straightforward. Most of the complications that arise in determining the expected number of annual exceed-ances relate to accounting for incomplete sampling. In general, the average number of exceedances per calendar year must be less than or equal to 1. In its simplest form, the number of exceedances at a monitoring site would be recorded for each calendar year and then averaged over the past 3 calendar years to determine if this average is less than or equal to 1.
The ozone standard states that the expected number of exceedances per year must be less than or equal to 1. The statistical term “expected number” is basically an arithmetic average. The following example explains what it would mean for an area to be in compliance with this type of standard. Suppose a monitoring station records a valid daily maximum hourly average ozone value for every day of the year during the past 3 years. At the end of each year, the number of days with maximum hourly concentrations above 0.12 ppm is determined and this number is averaged with the results of previous years. As long as this average remains “less than or equal to 1,” the area is in compliance.
In general, a valid daily maximum hourly average value may not be available for each day of the year, and it will be necessary to account for these missing values when estimating the number of exceedances for a particular calendar year. The purpose of these computations is to determine if the expected number of exceedances per year is less than or equal to 1. Thus, if a site has two or more observed exceedances each year, the standard is not met and it is not necessary to use the procedures of this section to account for incomplete sampling.
The term “missing value” is used here in the general sense to describe all days that do not have an associated ozone measurement. In some cases, a measurement might actually have been missed but in other cases no measurement may have been scheduled for that day. A daily maximum ozone value is defined to be the highest hourly ozone value recorded for the day. This daily maximum value is considered to be valid if 75 percent of the hours from 9:01 a.m. to 9:00 p.m. (LST) were measured or if the highest hour is greater than the level of the standard.
In some areas, the seasonal pattern of ozone is so pronounced that entire months need not be sampled because it is extremely unlikely that the standard would be exceeded. Any such waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some allowance should also be made for days for which valid daily maximum hourly values were not obtained but which would quite likely have been below the standard. Such an allowance introduces a complication in that it becomes necessary to define under what conditions a missing value may be assumed to have been less than the level of the standard. The following criterion may be used for ozone:
A missing daily maximum ozone value may be assumed to be less than the level of the standard if the valid daily maxima on both the preceding day and the following day do not exceed 75 percent of the level of the standard.
Let z denote the number of missing daily maximum values that may be assumed to be less than the standard. Then the following formula shall be used to estimate the expected number of exceedances for the year:
(*Indicates multiplication.)
This estimated number of exceedances shall be rounded to one decimal place (fractional parts equal to 0.05 round up).
It should be noted that N will be the total number of days in the year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR part 58.
The above equation may be interpreted intuitively in the following manner. The estimated number of exceedances is equal to the observed number of exceedances (v) plus an increment that accounts for incomplete sampling. There were (N-n) missing values for the year but a certain number of these, namely z, were assumed to be less than the standard. Therefore, (N-n-z) missing values are considered to include possible exceedances. The fraction of measured values that are above the level of the standard is v/n. It is assumed that this same fraction applies to the (N-n-z) missing values and that (v/n)*(N-n-z) of these values would also have exceeded the level of the standard.
1.
This appendix explains the data handling conventions and computations necessary for determining whether the national 8-hour primary and secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone air quality monitoring site. Ozone is measured in the ambient air by a reference method based on appendix D of this part. Data reporting, data handling, and computation procedures to be used in making comparisons between reported ozone concentrations and the level of the ozone standard are specified in the following sections. Whether to exclude, retain, or make adjustments to the data affected by stratospheric ozone intrusion or other natural events is subject to the approval of the appropriate Regional Administrator.
2.
2.1
2.1.1
2.1.2
(b) An ozone monitoring day shall be counted as a valid day if valid 8-hour averages are available for at least 75% of possible hours in the day (i.e., at least 18 of the 24 averages). In the event that less than 75% of the 8-hour averages are available, a day shall also be counted as a valid day if the daily maximum 8-hour average concentration for that day is greater than the level of the ambient standard.
2.2
2.3
(b) This comparison shall be based on three consecutive, complete calendar years of air quality monitoring data. This requirement is met for the three year period at a monitoring site if daily maximum 8-hour average concentrations are available for at least 90%, on average, of the days during the designated ozone monitoring season, with a minimum data completeness in any one year of at least 75% of the designated sampling days. When
(c) Years with concentrations greater than the level of the standard shall not be ignored on the ground that they have less than complete data. Thus, in computing the 3-year average fourth maximum concentration, calendar years with less than 75% data completeness shall be included in the computation if the average annual fourth maximum 8-hour concentration is greater than the level of the standard.
(d) Comparisons with the primary and secondary ozone standards are demonstrated by examples 1 and 2 in paragraphs (d)(1) and (d) (2) respectively as follows:
(1) As shown in example 1, the primary and secondary standards are met at this monitoring site because the 3-year average of the annual fourth-highest daily maximum 8-hour average ozone concentrations (i.e., 0.084 ppm) is less than or equal to 0.08 ppm. The data completeness requirement is also met because the average percent of days with valid ambient monitoring data is greater than 90%, and no single year has less than 75% data completeness.
(2) As shown in example 2, the primary and secondary standards are not met at this monitoring site because the 3-year average of the fourth-highest daily maximum 8-hour average ozone concentrations (i.e., 0.093 ppm) is greater than 0.08 ppm. Note that the ozone concentration data for 1994 is used in these computations, even though the data capture is less than 75%, because the average fourth-highest daily maximum 8-hour average concentration is greater than 0.08 ppm.
3.
1.0
1.1 This method provides for the measurement of the mass concentration of particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM
2.0
2.1 An air sampler draws ambient air at a constant flow rate into a specially shaped inlet where the suspended particulate matter is inertially separated into one or more size fractions within the PM
2.2 Each filter is weighed (after moisture equilibration) before and after use to determine the net weight (mass) gain due to collected PM
2.3 A method based on this principle will be considered a reference method only if (a) the associated sampler meets the requirements specified in this appendix and the requirements in part 53 of this chapter, and (b) the method has been designated as a reference method in accordance with part 53 of this chapter.
3.0
3.1 The lower limit of the mass concentration range is determined by the repeatability of filter tare weights, assuming the nominal air sample volume for the sampler. For samplers having an automatic filter-changing mechanism, there may be no upper limit. For samplers that do not have an automatic filter-changing mechanism, the upper limit is determined by the filter mass loading beyond which the sampler no longer maintains the operating flow rate within specified limits due to increased pressure drop across the loaded filter. This upper limit cannot be specified precisely because it is a complex function of the ambient particle size distribution and type, humidity, filter type, and perhaps other factors. Nevertheless, all samplers should be capable of measuring 24-hour PM
4.0
4.1 The precision of PM
5.0
5.1 Because the size of the particles making up ambient particulate matter varies over a wide range and the concentration of particles varies with particle size, it is difficult to define the absolute accuracy of PM
6.0
6.1
6.2
6.3
6.4
6.5
6.6
7.0
7.1
7.1.1 The sampler shall be designed to:
a. Draw the air sample into the sampler inlet and through the particle collection filter at a uniform face velocity.
b. Hold and seal the filter in a horizontal position so that sample air is drawn downward through the filter.
c. Allow the filter to be installed and removed conveniently.
d. Protect the filter and sampler from precipitation and prevent insects and other debris from being sampled.
e. Minimize air leaks that would cause error in the measurement of the air volume passing through the filter.
f. Discharge exhaust air at a sufficient distance from the sampler inlet to minimize the sampling of exhaust air.
g. Minimize the collection of dust from the supporting surface.
7.1.2 The sampler shall have a sample air inlet system that, when operated within a specified flow rate range, provides particle size discrimination characteristics meeting all of the applicable performance specifications prescribed in part 53 of this chapter. The sampler inlet shall show no significant wind direction dependence. The latter requirement can generally be satisfied by an inlet shape that is circularly symmetrical about a vertical axis.
7.1.3 The sampler shall have a flow control device capable of maintaining the sampler's operating flow rate within the flow rate limits specified for the sampler inlet over normal variations in line voltage and filter pressure drop.
7.1.4 The sampler shall provide a means to measure the total flow rate during the sampling period. A continuous flow recorder is recommended but not required. The flow measurement device shall be accurate to
7.1.5 A timing/control device capable of starting and stopping the sampler shall be used to obtain a sample collection period of 24
7.1.6 The sampler shall have an associated operation or instruction manual as required by part 53 of this chapter which includes detailed instructions on the calibration, operation, and maintenance of the sampler.
7.2
7.2.1
7.2.2
7.2.3
7.2.4
7.3
7.4
7.4.1 Temperature range: 15 to 30 C.
7.4.2 Temperature control:
7.4.3 Humidity range: 20% to 45% RH.
7.4.4 Humidity control:
7.5
8.0
8.1
8.1.1 Calibration of the sampler's flow measurement device is required to establish traceability of subsequent flow measurements to a primary standard. A flow rate transfer standard calibrated against a primary flow or volume standard shall be used to calibrate or verify the accuracy of the sampler's flow measurement device.
8.1.2 Particle size discrimination by inertial separation requires that specific air velocities be maintained in the sampler's air inlet system. Therefore, the flow rate through the sampler's inlet must be maintained throughout the sampling period within the design flow rate range specified by the manufacturer. Design flow rates are specified as actual volumetric flow rates, measured at existing conditions of temperature and pressure (Q
8.2
8.2.1 PM
8.2.2 Calibrate the flow rate transfer standard against a primary flow or volume standard traceable to NBS. Establish a calibration relationship (e.g., an equation or family of curves) such that traceability to the primary standard is accurate to within 2 percent over the expected range of ambient conditions (i.e., temperatures and pressures) under which the transfer standard will be used. Recalibrate the transfer standard periodically.
8.2.3 Following the sampler manufacturer's instruction manual, remove the sampler inlet and connect the flow rate transfer standard to the sampler such that the transfer standard accurately measures the sampler's flow rate. Make sure there are no leaks between the transfer standard and the sampler.
8.2.4 Choose a minimum of three flow rates (actual m
8.2.5 Following calibration, verify that the sampler is operating at its design flow rate (actual m
8.2.6 Replace the sampler inlet.
9.0
9.1 The sampler shall be operated in accordance with the specific guidance provided in the sampler manufacturer's instruction manual and in Reference 2. The general procedure given here assumes that the sampler's flow rate calibration is based on flow rates at ambient conditions (Q
9.2 Inspect each filter for pinholes, particles, and other imperfections. Establish a filter information record and assign an identification number to each filter.
9.3 Equilibrate each filter in the conditioning environment (see 7.4) for at least 24 hours.
9.4 Following equilibration, weigh each filter and record the presampling weight with the filter identification number.
9.5 Install a preweighed filter in the sampler following the instructions provided in the sampler manufacturer's instruction manual.
9.6 Turn on the sampler and allow it to establish run-temperature conditions. Record the flow indicator reading and, if needed, the ambient temperature and barometric pressure. Determine the sampler flow rate (actual m
9.7 If the flow rate is outside the acceptable range specified by the manufacturer, check for leaks, and if necessary, adjust the flow rate to the specified setpoint. Stop the sampler.
9.8 Set the timer to start and stop the sampler at appropriate times. Set the elapsed time meter to zero or record the initial meter reading.
9.9 Record the sample information (site location or identification number, sample date, filter identification number, and sampler model and serial number).
9.10 Sample for 24
9.11 Determine and record the average flow rate (Q
9.12 Carefully remove the filter from the sampler, following the sampler manufacturer's instruction manual. Touch only the outer edges of the filter.
9.13 Place the filter in a protective holder or container (e.g., petri dish, glassine envelope, or manila folder).
9.14 Record any factors such as meteorological conditions, construction activity, fires or dust storms, etc., that might be pertinent to the measurement on the filter information record.
9.15 Transport the exposed sample filter to the filter conditioning environment as soon as possible for equilibration and subsequent weighing.
9.16 Equilibrate the exposed filter in the conditioning environment for at least 24 hours under the same temperature and humidity conditions used for presampling filter equilibration (see 9.3).
9.17 Immediately after equilibration, reweigh the filter and record the postsampling weight with the filter identification number.
10.0
10.1 The PM
11.0
11.1 Calculate the average flow rate over the sampling period corrected to EPA reference conditions as Q
11.2 Calculate the total volume of air sampled as:
11.3 Calculate the PM
If more than one size fraction in the PM
12.0
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I, Principles. EPA-600/9-76-005, March 1976. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West St. Clair Street, Cincinnati, OH 45268.
2. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods. EPA-600/4-77-027a, May 1977. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West St. Clair Street, Cincinnati, OH 45268.
3. Clement, R.E., and F.W. Karasek. Sample Composition Changes in Sampling and Analysis of Organic Compounds in Aerosols. Int. J. Environ. Analyt. Chem., 7:109, 1979.
4. Lee, R.E., Jr., and J. Wagman. A Sampling Anomaly in the Determination of Atmospheric Sulfate Concentration. Amer. Ind. Hyg. Assoc. J., 27:266, 1966.
5. Appel, B.R., S.M. Wall, Y. Tokiwa, and M. Haik. Interference Effects in Sampling Particulate Nitrate in Ambient Air. Atmos. Environ., 13:319, 1979.
6. Coutant, R.W. Effect of Environmental Variables on Collection of Atmospheric Sulfate. Environ. Sci. Technol., 11:873, 1977.
7. Spicer, C.W., and P. Schumacher. Interference in Sampling Atmospheric Particulate Nitrate. Atmos. Environ., 11:873, 1977.
8. Appel, B.R., Y. Tokiwa, and M. Haik. Sampling of Nitrates in Ambient Air. Atmos. Environ., 15:283, 1981.
9. Spicer, C.W., and P.M. Schumacher. Particulate Nitrate: Laboratory and Field Studies of Major Sampling Interferences. Atmos. Environ., 13:543, 1979.
10. Appel, B.R. Letter to Larry Purdue, U.S. EPA, Environmental Monitoring and Support Laboratory. March 18, 1982, Docket No. A-82-37, II-I-1.
11. Pierson, W.R., W.W. Brachaczek, T.J. Korniski, T.J. Truex, and J.W. Butler. Artifact Formation of Sulfate, Nitrate, and Hydrogen Ion on Backup Filters: Allegheny Mountain Experiment. J. Air Pollut. Control Assoc., 30:30, 1980.
12. Dunwoody, C.L. Rapid Nitrate Loss From PM
13. Harrell, R.M. Measuring the Alkalinity of Hi-Vol Air Filters. EMSL/RTP-SOP-QAD-534, October 1985. Available from the U.S. Environmental Protection Agency, EMSL/QAD, Research Triangle Park, NC 27711.
14. Smith, F., P.S. Wohlschlegel, R.S.C. Rogers, and D.J. Mulligan. Investigation of Flow Rate Calibration Procedures Associated With the High Volume Method for Determination of Suspended Particulates. EPA-600/4-78-047, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1978.
1.0
(a) This appendix explains the computations necessary for analyzing particulate matter data to determine attainment of the 24-hour and annual standards specified in 40 CFR 50.6. For the primary and secondary standards, particulate matter is measured in the ambient air as PM
(b) The terms used in this appendix are defined as follows:
(c) Although the discussion in this appendix focuses on monitored data, the same principles apply to modeling data, subject to EPA modeling guidelines.
2.0
2.1
(a) Under 40 CFR 50.6(a) the 24-hour primary and secondary standards are attained when the expected number of exceedances per year at each monitoring site is less than or equal to one. In the simplest case, the number of expected exceedances at a site is determined by recording the number of exceedances in each calendar year and then averaging them over the past 3 calendar years. Situations in which 3 years of data are not available and possible adjustments for unusual events or trends are discussed in sections 2.3 and 2.4 of this appendix. Further, when data for a year are incomplete, it is necessary to compute an estimated number of exceedances for that year by adjusting the observed number of exceedances. This procedure, performed by calendar quarter, is described in section 3.0 of this appendix. The expected number of exceedances is then estimated by averaging the individual annual estimates for the past 3 years.
(b) The comparison with the allowable expected exceedance rate of one per year is made in terms of a number rounded to the nearest tenth (fractional values equal to or greater than 0.05 are to be rounded up; e.g., an exceedance rate of 1.05 would be rounded to 1.1, which is the lowest rate for nonattainment).
2.2
2.3
(a) 40 CFR 58.13 specifies the required minimum frequency of sampling for PM
(b) To demonstrate attainment of either the annual or 24-hour standards at a monitoring site, the monitor must provide sufficient data to perform the required calculations of sections 3.0 and 4.0 of this appendix. The amount of data required varies with the sampling frequency, data capture rate and the number of years of record. In all cases, 3 years of representative monitoring data that meet the 75 percent criterion of the previous paragraph should be utilized, if available, and would suffice. More than 3 years may be considered, if all additional representative years of data meeting the 75 percent criterion are utilized. Data not meeting these criteria may also suffice to show attainment; however, such exceptions will have to be approved by the appropriate Regional Administrator in accordance with EPA guidance.
(c) There are less stringent data requirements for showing that a monitor has failed an attainment test and thus has recorded a violation of the particulate matter standards. Although it is generally necessary to meet the minimum 75 percent data capture requirement per quarter to use the computational equations described in sections 3.0 and 4.0 of this appendix, this criterion does not apply when less data is sufficient to unambiguously establish nonattainment. The following examples illustrate how nonattainment can be demonstrated when a site fails to meet the completeness criteria. Nonattainment of the 24-hour primary standards can be established by the observed annual number of exceedances (e.g., four observed exceedances in a single year), or by the estimated number of exceedances derived from the observed number of exceedances and the required number of scheduled samples (e.g., two observed exceedances with every other day sampling). Nonattainment of the annual standards can be demonstrated on the basis of quarterly mean concentrations developed from observed data combined with one-half the minimum detectable concentration substituted for missing values. In both cases, expected annual values must exceed the levels allowed by the standards.
2.4
(a) An exceptional event is an uncontrollable event caused by natural sources of particulate matter or an event that is not expected to recur at a given location. Inclusion of such a value in the computation of exceedances or averages could result in inappropriate estimates of their respective expected annual values. To reduce the effect of unusual events, more than 3 years of representative data may be used. Alternatively, other techniques, such as the use of statistical models or the use of historical data could be considered so that the event may be discounted or weighted according to the likelihood that it will recur. The use of such techniques is subject to the approval of the appropriate Regional Administrator in accordance with EPA guidance.
(b) In cases where long-term trends in emissions and air quality are evident, mathematical techniques should be applied to account for the trends to ensure that the expected annual values are not inappropriately biased by unrepresentative data. In the simplest case, if 3 years of data are available under stable emission conditions, this data should be used. In the event of a trend or shift in emission patterns, either the most recent representative year(s) could be used or statistical techniques or models could be used in conjunction with previous years of data to adjust for trends. The use of less than 3 years of data, and any adjustments are subject to the approval of the appropriate Regional Administrator in accordance with EPA guidance.
3.0
3.1
(a) If PM
(b) The estimated number of exceedances for a calendar quarter must be rounded to the nearest hundredth (fractional values equal to or greater than 0.005 must be rounded up).
(c) The estimated number of exceedances for the year, e, is the sum of the estimates for each calendar quarter.
(d) The estimated number of exceedances for a single year must be rounded to one decimal place (fractional values equal to or greater than 0.05 are to be rounded up). The expected number of exceedances is then estimated by averaging the individual annual estimates for the most recent 3 or more representative years of data. The expected number of exceedances must be rounded to one decimal place (fractional values equal to or greater than 0.05 are to be rounded up).
(e) The adjustment for incomplete data will not be necessary for monitoring or modeling data which constitutes a complete record, i.e., 365 days per year.
(f) To reduce the potential for overestimating the number of expected exceedances, the correction for missing data will not be required for a calendar quarter in which the first observed exceedance has occurred if:
(1) There was only one exceedance in the calendar quarter;
(2) Everyday sampling is subsequently initiated and maintained for 4 calendar quarters in accordance with 40 CFR 58.13; and
(3) Data capture of 75 percent is achieved during the required period of everyday sampling. In addition, if the first exceedance is observed in a calendar quarter in which the monitor is already sampling every day, no adjustment for missing data will be made to the first exceedance if a 75 percent data capture rate was achieved in the quarter in which it was observed.
a. During a particular calendar quarter, 39 out of a possible 92 samples were recorded, with one observed exceedance of the 24-hour standard. Using Equation 1, the estimated number of exceedances for the quarter is:
b. If the estimated exceedances for the other 3 calendar quarters in the year were 2.30, 0.0 and 0.0, then, using Equation 2, the estimated number of exceedances for the year is 2.36=2.30=0.0=0.0 which equals 4.66 or 4.7. If no exceedances were observed for the 2 previous years, then the expected number of exceedances is estimated by: (1/3)×(4.7=0=0)=1.57 or 1.6. Since 1.6 exceeds the allowable number of expected exceedances, this monitoring site would fail the attainment test.
In this example, everyday sampling was initiated following the first observed exceedance as required by 40 CFR 58.13. Accordingly, the first observed exceedance would not be adjusted for incomplete sampling. During the next three quarters, 1.2 exceedances were estimated. In this case, the estimated exceedances for the year would be 1.0=1.2=0.0=0.0 which equals 2.2. If, as before, no exceedances were observed for the two previous years, then the estimated exceedances for the 3-year period would then be (1/3)×(2.2=0.0=0.0)=0.7, and the monitoring site would
3.2
(a) If a systematic sampling schedule is used and sampling is performed on days in addition to the days specified by the systematic sampling schedule, e.g., during episodes of high pollution, then an adjustment must be made in the eqution for the estimation of exceedances. Such an adjustment is needed to eliminate the bias in the estimate of the quarterly and annual number of exceedances that would occur if the chance of an exceedance is different for scheduled than for non-scheduled days, as would be the case with episode sampling.
(b) The required adjustment treats the systematic sampling schedule as a stratified sampling plan. If the period from one scheduled sample until the day preceding the next scheduled sample is defined as a sampling stratum, then there is one stratum for each scheduled sampling day. An average number of observed exceedances is computed for each of these sampling strata. With nonscheduled sampling days, the estimated number of exceedances is defined as:
(c) Note that if only one sample value is recorded in each stratum, then Equation 3 reduces to Equation 1.
A monitoring site samples according to a systematic sampling schedule of one sample every 6 days, for a total of 15 scheduled samples in a quarter out of a total of 92 possible samples. During one 6-day period, potential episode levels of PM
4.0
4.1
(b) The quarterly mean, expressed in μg/m
(c) The annual mean is calculated by using the following equation:
(d) The average of quarterly means must be rounded to the nearest tenth (fractional values of 0.05 should be rounded up).
(e) The use of quarterly averages to compute the annual average will not be necessary for monitoring or modeling data which results in a complete record, i.e., 365 days per year.
(f) The expected annual mean is estimated as the average of three or more annual means. This multi-year estimate, expressed in μg/m
Using Equation 4, the quarterly means are calculated for each calendar quarter. If the quarterly means are 52.4, 75.3, 82.1, and 63.2 μg/m
4.2
(b) If one sample value is recorded in each stratum, Equation 6 reduces to a simple arithmetic average of the observed values as described by Equation 4.
a. During one calendar quarter, 9 observations were recorded. These samples were distributed among 7 sampling strata, with 3 observations in one stratum. The concentrations of the 3 observations in the single stratum were 202, 242, and 180 μg/m
b. Although 24-hour measurements are rounded to the nearest 10 μg/m
1.0
1.1 This method provides for the measurement of the mass concentration of fine particulate matter having an aerodynamic diameter less than or equal to a nominal 2.5 micrometers (PM
1.2 This method will be considered a reference method for purposes of part 58 of this chapter only if:
(a) The associated sampler meets the requirements specified in this appendix and the applicable requirements in part 53 of this chapter, and
(b) The method and associated sampler have been designated as a reference method in accordance with part 53 of this chapter.
1.3 PM
2.0
2.1 An electrically powered air sampler draws ambient air at a constant volumetric flow rate into a specially shaped inlet and
2.2 Each filter is weighed (after moisture and temperature conditioning) before and after sample collection to determine the net gain due to collected PM
3.0
3.1
3.2
3.3
4.0
4.1 Because the size and volatility of the particles making up ambient particulate matter vary over a wide range and the mass concentration of particles varies with particle size, it is difficult to define the accuracy of PM
4.2
4.3
4.4
5.0
5.1 Tests to establish initial operational precision for each reference method sampler are specified as a part of the requirements for designation as a reference method under § 53.58 of this chapter.
5.2
6.0
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.9.1
6.9.2
6.10
6.11
7.0
7.1
(a) Provide automatic control of sample volumetric flow rate and other operational parameters.
(b) Monitor these operational parameters as well as ambient temperature and pressure.
(c) Provide this information to the sampler operator at the end of each sample period in
7.2
7.3
7.3.1
7.3.2
7.3.3
7.3.4
7.3.4.1 The impactor (particle size separator) shall be fabricated as indicated in Figures L-20 through L-24 of this appendix and shall meet all associated requirements. Following the manufacture and finishing of each upper impactor housing (Figure L-21 of this appendix), the dimension of the impaction jet must be verified by the manufacturer using Class ZZ go/no-go plug gauges that are traceable to NIST.
7.3.4.2 Impactor filter specifications:
(a) Size. Circular, 35 to 37 mm diameter.
(b) Medium. Borosilicate glass fiber, without binder.
(c) Pore size. 1 to 1.5 micrometer, as measured by ASTM F 316-80.
(d) Thickness. 300 to 500 micrometers.
7.3.4.3 Impactor oil specifications:
(a) Composition. Tetra-methyl-tetra-phenyl-trisiloxane, single-compound diffusion oil.
(b) Vapor pressure. Maximum 2 x 10
(c) Viscosity. 36 to 40 centistokes at 25 °C.
(d) Density. 1.06 to 1.07 g/cm
(e) Quantity. 1 mL
7.3.5
(a) The lower portion of the filter holder assembly shall be of a design and construction that:
(1) Mates with the upper portion of the assembly to complete the filter holder assembly,
(2) Completes both the external air seal and the internal filter cassette seal such that all seals are reliable over repeated filter changings, and
(3) Facilitates repeated changing of the filter cassette by the sampler operator.
(b) Leak-test performance requirements for the filter holder assembly are included in section 7.4.6 of this appendix.
(c) If additional or multiple filters are stored in the sampler as part of an automatic sequential sample capability, all such filters, unless they are currently and directly installed in a sampling channel or sampling configuration (either active or inactive), shall be covered or (preferably) sealed in such a way as to:
(1) Preclude significant exposure of the filter to possible contamination or accumulation of dust, insects, or other material that may be present in the ambient air, sampler, or sampler ventilation air during storage periods either before or after sampling; and
(2) To minimize loss of volatile or semi-volatile PM sample components during storage of the filter following the sample period.
7.3.6
7.3.7
7.3.8
7.4
7.4.1
7.4.2
7.4.3
7.4.3.1 The volumetric flow rate, measured or averaged over intervals of not more than 5 minutes over a 24-hour period, shall not vary more than
7.4.3.2 The coefficient of variation (sample standard deviation divided by the mean) of the flow rate, measured over a 24-hour period, shall not be greater than 2 percent.
7.4.3.3 The amplitude of short-term flow rate pulsations, such as may originate from some types of vacuum pumps, shall be attenuated such that they do not cause significant flow measurement error or affect the collection of particles on the particle collection filter.
7.4.4
7.4.5
7.4.5.1 The sampler shall provide a means to measure and indicate the instantaneous sample air flow rate, which shall be measured as volumetric flow rate at the temperature and pressure of the sample air entering the inlet, with an accuracy of
7.4.5.2 During each sample period, the sampler's flow rate measurement system shall automatically monitor the sample volumetric flow rate, obtaining flow rate measurements at intervals of not greater than 30 seconds.
(a) Using these interval flow rate measurements, the sampler shall determine or calculate the following flow-related parameters, scaled in the specified engineering units:
(1) The instantaneous or interval-average flow rate, in L/min.
(2) The value of the average sample flow rate for the sample period, in L/min.
(3) The value of the coefficient of variation (sample standard deviation divided by the
(4) The occurrence of any time interval during the sample period in which the measured sample flow rate exceeds a range of
(5) The value of the integrated total sample volume for the sample period, in m
(b) Determination or calculation of these values shall properly exclude periods when the sampler is inoperative due to temporary interruption of electrical power, under section 7.4.13 of this appendix, or flow rate cut off, under section 7.4.4 of this appendix.
(c) These parameters shall be accessible to the sampler operator as specified in table L-1 of section 7.4.19 of this appendix. In addition, it is strongly encouraged that the flow rate for each 5-minute interval during the sample period be available to the operator following the end of the sample period.
7.4.6
7.4.6.1
(a) The suggested technique for the operator to use for this leak test is as follows:
(1) Remove the sampler inlet and installs the flow rate measurement adapter supplied with the sampler, under section 7.3.6 of this appendix.
(2) Close the valve on the flow rate measurement adapter and use the sampler air pump to draw a partial vacuum in the sampler, including (at least) the impactor, filter holder assembly (filter in place), flow measurement device, and interconnections between these devices, of at least 55 mm Hg (75 cm water column), measured at a location downstream of the filter holder assembly.
(3) Plug the flow system downstream of these components to isolate the components under vacuum from the pump, such as with a built-in valve.
(4) Stop the pump.
(5) Measure the trapped vacuum in the sampler with a built-in pressure measuring device.
(6) (i) Measure the vacuum in the sampler with the built-in pressure measuring device again at a later time at least 10 minutes after the first pressure measurement.
(ii)
(7) Upon completion of the test, open the adaptor valve, remove the adaptor and plugs, and restore the sampler to the normal operating configuration.
(b) The associated leak test procedure shall require that for successful passage of this test, the difference between the two pressure measurements shall not be greater than the number of mm of Hg specified for the sampler by the manufacturer, based on the actual internal volume of the sampler, that indicates a leak of less than 80 mL/min.
(c) Variations of the suggested technique or an alternative external leak test technique may be required for samplers whose design or configuration would make the suggested technique impossible or impractical. The specific proposed external leak test procedure, or particularly an alternative leak test technique, proposed for a particular candidate sampler may be described and submitted to the EPA for specific individual acceptability either as part of a reference or equivalent method application under part 53 of this chapter or in writing in advance of such an intended application under part 53 of this chapter.
7.4.6.2
(a) The suggested technique for the operator to use for this leak test is as follows:
(1) Carry out an external leak test as provided under section 7.4.6.1 of this appendix which indicates successful passage of the prescribed external leak test.
(2) Install a flow-impervious membrane material in the filter cassette, either with or without a filter, as appropriate, which effectively prevents air flow through the filter.
(3) Use the sampler air pump to draw a partial vacuum in the sampler, downstream of the filter holder assembly, of at least 55 mm Hg (75 cm water column).
(4) Plug the flow system downstream of the filter holder to isolate the components under
(5) Stop the pump.
(6) Measure the trapped vacuum in the sampler with a built-in pressure measuring device.
(7) Measure the vacuum in the sampler with the built-in pressure measuring device again at a later time at least 10 minutes after the first pressure measurement.
(8) Remove the flow plug and membrane and restore the sampler to the normal operating configuration.
(b) The associated leak test procedure shall require that for successful passage of this test, the difference between the two pressure measurements shall not be greater than the number of mm of Hg specified for the sampler by the manufacturer, based on the actual internal volume of the portion of the sampler under vacuum, that indicates a leak of less than 80 mL/min.
(c) Variations of the suggested technique or an alternative internal, filter bypass leak test technique may be required for samplers whose design or configuration would make the suggested technique impossible or impractical. The specific proposed internal leak test procedure, or particularly an alternative internal leak test technique proposed for a particular candidate sampler may be described and submitted to the EPA for specific individual acceptability either as part of a reference or equivalent method application under part 53 of this chapter or in writing in advance of such intended application under part 53 of this chapter.
7.4.7
7.4.7.1
7.4.7.2
7.4.7.3
7.4.8
7.4.8.1 The ambient temperature sensor shall be mounted external to the sampler enclosure and shall have a passive, naturally ventilated sun shield. The sensor shall be located such that the entire sun shield is at least 5 cm above the horizontal plane of the sampler case or enclosure (disregarding the inlet and downtube) and external to the vertical plane of the nearest side or protuberance of the sampler case or enclosure. The maximum temperature measurement error of the ambient temperature measurement system shall be less than 1.6 °C at 1 m/s wind speed and 1000 W/m2 solar radiation intensity.
7.4.8.2 The ambient temperature sensor shall be of such a design and mounted in such a way as to facilitate its convenient dismounting and immersion in a liquid for calibration and comparison to the filter temperature sensor, under section 7.4.11 of this appendix.
7.4.8.3 This ambient temperature measurement shall be updated at least every 30 seconds during both sampling and standby (non-sampling) modes of operation. A visual indication of the current (most recent) value of the ambient temperature measurement, updated at least every 30 seconds, shall be available to the sampler operator during both sampling and standby (non-sampling) modes of operation, as specified in table L-1 of section 7.4.19 of this appendix.
7.4.8.4 This ambient temperature measurement shall be used for the purpose of monitoring filter temperature deviation from ambient temperature, as required by section 7.4.11 of this appendix, and may be used for purposes of effecting filter temperature control, under section 7.4.10 of this appendix, or computation of volumetric flow rate, under sections 7.4.1 to 7.4.5 of this appendix, if appropriate.
7.4.8.5 Following the end of each sample period, the sampler shall report the maximum, minimum, and average temperature for the sample period, as specified in table L-1 of section 7.4.19 of this appendix.
7.4.9
7.4.10
7.4.11
7.4.11.1 The sampler shall have the capability to monitor the temperature of the sample filter (all sample filters for sequential samplers) over the range of -30 to =45 °C during both sampling and non-sampling periods. While the exact location of this temperature sensor is not explicitly specified, the filter temperature measurement system must demonstrate agreement, within 1 °C, with a test temperature sensor located within 1 cm of the center of the filter downstream of the filter during both sampling and non-sampling modes, as specified in the filter temperature measurement test described in part 53, subpart E of this chapter. This filter temperature measurement shall have a resolution of 0.1 °C and accuracy of
7.4.11.2 The filter temperature measurement shall be updated at least every 30 seconds during both sampling and standby (non-sampling) modes of operation. A visual indication of the current (most recent) value of the filter temperature measurement, updated at least every 30 seconds, shall be available to the sampler operator during both sampling and standby (non-sampling) modes of operation, as specified in table L-1 of section 7.4.19 of this appendix.
7.4.11.3 For sequential samplers, the temperature of each filter shall be measured individually unless it can be shown, as specified in the filter temperature measurement test described in § 53.57 of this chapter, that the temperature of each filter can be represented by fewer temperature sensors.
7.4.11.4 The sampler shall also provide a warning flag indicator following any occurrence in which the filter temperature (any filter temperature for sequential samplers) exceeds the ambient temperature by more than 5 °C for more than 30 consecutive minutes during either the sampling or post-sampling periods of operation, as specified in table L-1 of section 7.4.19 of this appendix, under section 10.12 of this appendix, regarding sample validity when a warning flag occurs. It is further recommended (not required) that the sampler be capable of recording the maximum differential between the measured filter temperature and the ambient temperature and its time and date of occurrence during both sampling and post-sampling (non-sampling) modes of operation and providing for those data to be accessible to the sampler operator following the end of the sample period, as suggested in table L-1 of section 7.4.19 of this appendix.
7.4.12
(a) The sampler shall have a programmable real-time clock timing/control system that:
(1) Is capable of maintaining local time and date, including year, month, day-of-month, hour, minute, and second to an accuracy of
(2) Provides a visual indication of the current system time, including year, month, day-of-month, hour, and minute, updated at least each minute, for operator verification.
(3) Provides appropriate operator controls for setting the correct local time and date.
(4) Is capable of starting the sample collection period and sample air flow at a specific, operator-settable time and date, and stopping the sample air flow and terminating the sampler collection period 24 hours (1440 minutes) later, or at a specific, operator-settable time and date.
(b) These start and stop times shall be readily settable by the sampler operator to within
7.4.13
7.4.14
7.4.15
7.4.15.1 The sampler shall be operable and function as specified herein when operated on an electrical power supply voltage of 105 to 125 volts AC (RMS) at a frequency of 59 to 61 Hz. Optional operation as specified at additional power supply voltages and/or frequencies shall not be precluded by this requirement.
7.4.15.2 The design and construction of the sampler shall comply with all applicable National Electrical Code and Underwriters Laboratories electrical safety requirements.
7.4.15.3 The design of all electrical and electronic controls shall be such as to provide reasonable resistance to interference or malfunction from ordinary or typical levels of stray electromagnetic fields (EMF) as may be found at various monitoring sites and from typical levels of electrical transients or electronic noise as may often or occasionally be present on various electrical power lines.
7.4.15.4 In the event of temporary loss of electrical supply power to the sampler, the sampler shall not be required to sample or provide other specified functions during such loss of power, except that the internal clock/timer system shall maintain its local time and date setting within
7.4.15.5 The sampler shall have the capability to record and retain a record of the year, month, day-of-month, hour, and minute of the start of each power interruption of more than 1 minute duration, up to 10 such power interruptions per sample period. (More than 10 such power interruptions shall invalidate the sample, except where an exceedance is measured, under section 3.3 of this appendix.) The sampler shall provide for these power interruption data to be available to the sampler operator following the end of the sample period, as specified in table L-1 of section 7.4.19 of this appendix.
7.4.16
7.4.17
7.4.18
7.4.19
8.0
8.1
8.2
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.3
8.3.1 New filters should be placed in the conditioning environment immediately upon arrival and stored there until the pre-sampling weighing. See reference 2 in section 13.0 of this appendix for additional guidance.
8.3.2 The analytical balance shall be located in the same controlled environment in which the filters are conditioned. The filters shall be weighed immediately following the conditioning period without intermediate or transient exposure to other conditions or environments.
8.3.3 Filters must be conditioned at the same conditions (humidity within
8.3.4 Both the pre- and post-sampling weighings should be carried out on the same analytical balance, using an effective technique to neutralize static charges on the filter, under reference 2 in section 13.0 of this appendix. If possible, both weighings should be carried out by the same analyst.
8.3.5 The pre-sampling (tare) weighing shall be within 30 days of the sampling period.
8.3.6 The post-sampling conditioning and weighing shall be completed within 240 hours (10 days) after the end of the sample period, unless the filter sample is maintained at 4 °C or less during the entire time between retrieval from the sampler and the start of the conditioning, in which case the period shall not exceed 30 days. Reference 2 in section 13.0 of this appendix has additional guidance on transport of cooled filters.
8.3.7
8.3.7.1 New field blank filters shall be weighed along with the pre-sampling (tare) weighing of each lot of PM
8.3.7.2 New laboratory blank filters shall be weighed along with the pre-sampling (tare) weighing of each set of PM
8.3.8 Additional guidance for proper filter weighing and related quality assurance activities is provided in reference 2 in section 13.0 of this appendix.
9.0
9.1
9.1.1 Multipoint calibration and single-point verification of the sampler's flow rate measurement device must be performed periodically to establish and maintain traceability of subsequent flow measurements to a flow rate standard.
9.1.2 An authoritative flow rate standard shall be used for calibrating or verifying the sampler's flow rate measurement device with an accuracy of
9.1.3 The sampler's flow rate measurement device shall be re-calibrated after electromechanical maintenance or transport of the sampler.
9.2
9.2.1 PM
9.2.2 The flow rate standard used for flow rate calibration shall have its own certification and be traceable to a NIST primary standard for volume or flow rate. A calibration relationship for the flow rate standard, e.g., an equation, curve, or family of curves relating actual flow rate (Q
9.2.3 The sampler flow rate measurement device shall be calibrated or verified by removing the sampler inlet and connecting the flow rate standard to the sampler's downtube in accordance with the operation/instruction manual, such that the flow rate standard accurately measures the sampler's flow rate. The sampler operator shall first carry out a sampler leak check and confirm that the sampler passes the leak test and then verify that no leaks exist between the flow rate standard and the sampler.
9.2.4 The calibration relationship between the flow rate (in actual L/min) indicated by the flow rate standard and by the sampler's flow rate measurement device shall be established or verified in accordance with the sampler operation/instruction manual. Temperature and pressure corrections to the flow rate indicated by the flow rate standard may be required for certain types of flow rate standards. Calibration of the sampler's flow rate measurement device shall consist of at least three separate flow rate measurements (multipoint calibration) evenly spaced within the range of -10 percent to =10 percent of the sampler's operational flow rate, section 7.4.1 of this appendix. Verification of the sampler's flow rate shall consist of one flow rate measurement at the sampler's operational flow rate. The sampler operation/instruction manual and reference 2 in section 13.0 of this appendix provide additional guidance.
9.2.5 If during a flow rate verification the reading of the sampler's flow rate indicator or measurement device differs by
9.2.6 Following the calibration or verification, the flow rate standard shall be removed from the sampler and the sampler inlet shall be reinstalled. Then the sampler's normal operating flow rate (in L/min) shall be determined with a clean filter in place. If the flow rate indicated by the sampler differs by
9.3 Periodic calibration or verification of the calibration of the sampler's ambient temperature, filter temperature, and barometric pressure measurement systems is also required. Reference 3 of section 13.0 of this appendix contains additional guidance.
10.0
10.1 The sampler shall be set up, calibrated, and operated in accordance with the specific, detailed guidance provided in the specific sampler's operation or instruction manual and in accordance with a specific quality assurance program developed and established by the user, based on applicable supplementary guidance provided in reference 2 in section 13.0 of this appendix.
10.2 Each new sample filter shall be inspected for correct type and size and for pinholes, particles, and other imperfections. Unacceptable filters should be discarded. A unique identification number shall be assigned to each filter, and an information record shall be established for each filter. If the filter identification number is not or cannot be marked directly on the filter, alternative means, such as a number-identified storage container, must be established to maintain positive filter identification.
10.3 Each filter shall be conditioned in the conditioning environment in accordance with the requirements specified in section 8.2 of this appendix.
10.4 Following conditioning, each filter shall be weighed in accordance with the requirements specified in section 8.0 of this appendix and the presampling weight recorded with the filter identification number.
10.5 A numbered and preweighed filter shall be installed in the sampler following the instructions provided in the sampler operation or instruction manual.
10.6 The sampler shall be checked and prepared for sample collection in accordance with instructions provided in the sampler operation or instruction manual and with the specific quality assurance program established for the sampler by the user.
10.7 The sampler's timer shall be set to start the sample collection at the beginning of the desired sample period and stop the sample collection 24 hours later.
10.8 Information related to the sample collection (site location or identification number, sample date, filter identification number, and sampler model and serial number) shall be recorded and, if appropriate, entered into the sampler.
10.9 The sampler shall be allowed to collect the PM
10.10 Within 96 hours of the end of the sample collection period, the filter, while still contained in the filter cassette, shall be carefully removed from the sampler, following the procedure provided in the sampler operation or instruction manual and the quality assurance program, and placed in a protective container. The protective container shall contain no loose material that could be transferred to the filter. The protective container shall hold the filter cassette securely such that the cover shall not come in contact with the filter's surfaces. Reference 2 in section 13.0 of this appendix contains additional information.
10.11 The total sample volume in actual m
10.12 All factors related to the validity or representativeness of the sample, such as sampler tampering or malfunctions, unusual meteorological conditions, construction activity, fires or dust storms, etc. shall be recorded as required by the local quality assurance program. The occurrence of a flag warning during a sample period shall not necessarily indicate an invalid sample but rather shall indicate the need for specific review of the QC data by a quality assurance officer to determine sample validity.
10.13 After retrieval from the sampler, the exposed filter containing the PM
10.14. The exposed filter containing the PM
10.15. The filter shall be reweighed immediately after conditioning in accordance with the requirements specified in section 8.0 of this appendix, and the postsampling weight shall be recorded with the filter identification number.
10.16 The PM
11.0
12.0
12.1 (a) The PM
Total sample time must be between 1,380 and 1,500 minutes (23 and 25 hrs) for a fully valid PM
13.0
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I, Principles. EPA/600/R-94/038a, April 1994. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268.
2. Copies of section 2.12 of the Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods, EPA/600/R-94/038b, are available from Department E (MD-77B), U.S. EPA, Research Triangle Park, NC 27711.
3. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume IV: Meteorological Measurements, (Revised Edition) EPA/600/R-94/038d, March, 1995. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268.
4. Military standard specification (mil. spec.) 8625F, Type II, Class 1 as listed in Department of Defense Index of Specifications and Standards (DODISS), available from DODSSP-Customer Service, Standardization Documents Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 1911-5094.
14.0
1.0
1.1 This method provides for the measurement of the mass concentration of particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM
2.0
2.1 An air sampler draws ambient air at a constant flow rate into a specially shaped inlet where the suspended particulate matter is inertially separated into one or more size fractions within the PM
2.2 Each filter is weighed (after moisture equilibration) before and after use to determine the net weight (mass) gain due to collected PM
2.3 A method based on this principle will be considered a reference method only if the associated sampler meets the requirements specified in this appendix and the requirements in part 53 of this chapter, and the method has been designated as a reference method in accordance with part 53 of this chapter.
3.0
3.1 The lower limit of the mass concentration range is determined by the repeatability of filter tare weights, assuming the nominal air sample volume for the sampler. For samplers having an automatic filter-changing mechanism, there may be no upper limit. For samplers that do not have an automatic filter-changing mechanism, the upper limit is determined by the filter mass loading beyond which the sampler no longer maintains the operating flow rate within specified limits due to increased pressure drop across the loaded filter. This upper limit cannot be specified precisely because it is a complex function of the ambient particle size distribution and type, humidity, filter type, and perhaps other factors. Nevertheless, all samplers should be capable of measuring 24-hour PM
4.0
4.1 The precision of PM
5.0
5.1 Because the size of the particles making up ambient particulate matter varies over a wide range and the concentration of particles varies with particle size, it is difficult to define the absolute accuracy of PM
6.0
6.1
6.2
6.3
6.4
6.5
6.6
7.0
7.1 PM
7.1.1 The sampler shall be designed to:
(a) Draw the air sample into the sampler inlet and through the particle collection filter at a uniform face velocity.
(b) Hold and seal the filter in a horizontal position so that sample air is drawn downward through the filter.
(c) Allow the filter to be installed and removed conveniently.
(d) Protect the filter and sampler from precipitation and prevent insects and other debris from being sampled.
(e) Minimize air leaks that would cause error in the measurement of the air volume passing through the filter.
(f) Discharge exhaust air at a sufficient distance from the sampler inlet to minimize the sampling of exhaust air.
(g) Minimize the collection of dust from the supporting surface.
7.1.2 The sampler shall have a sample air inlet system that, when operated within a specified flow rate range, provides particle size discrimination characteristics meeting all of the applicable performance specifications prescribed in part 53 of this chapter. The sampler inlet shall show no significant wind direction dependence. The latter requirement can generally be satisfied by an inlet shape that is circularly symmetrical about a vertical axis.
7.1.3 The sampler shall have a flow control device capable of maintaining the sampler's operating flow rate within the flow rate limits specified for the sampler inlet over normal variations in line voltage and filter pressure drop.
7.1.4 The sampler shall provide a means to measure the total flow rate during the sampling period. A continuous flow recorder is recommended but not required. The flow measurement device shall be accurate to
7.1.5 A timing/control device capable of starting and stopping the sampler shall be used to obtain a sample collection period of 24
7.1.6 The sampler shall have an associated operation or instruction manual as required by part 53 of this chapter which includes detailed instructions on the calibration, operation, and maintenance of the sampler.
7.2
7.2.1
7.2.2
7.2.3
7.2.4
7.3
7.4
7.4.1
7.4.2
7.4.3
7.4.4
7.5
8.0
8.1
8.1.1 Calibration of the sampler's flow measurement device is required to establish traceability of subsequent flow measurements to a primary standard. A flow rate transfer standard calibrated against a primary flow or volume standard shall be used to calibrate or verify the accuracy of the sampler's flow measurement device.
8.1.2 Particle size discrimination by inertial separation requires that specific air velocities be maintained in the sampler's air inlet system. Therefore, the flow rate through the sampler's inlet must be maintained throughout the sampling period within the design flow rate range specified by the manufacturer. Design flow rates are specified as actual volumetric flow rates, measured at existing conditions of temperature and pressure (Q
8.2
8.2.1 PM
8.2.2 Calibrate the flow rate transfer standard against a primary flow or volume standard traceable to NIST. Establish a calibration relationship, e.g., an equation or family of curves, such that traceability to the primary standard is accurate to within 2 percent over the expected range of ambient conditions, i.e., temperatures and pressures, under which the transfer standard will be used. Recalibrate the transfer standard periodically.
8.2.3 Following the sampler manufacturer's instruction manual, remove the sampler inlet and connect the flow rate transfer standard to the sampler such that the transfer standard accurately measures the sampler's flow rate. Make sure there are no leaks between the transfer standard and the sampler.
8.2.4 Choose a minimum of three flow rates (actual m
8.2.5 Following calibration, verify that the sampler is operating at its design flow rate (actual m
8.2.6 Replace the sampler inlet.
9.0
9.1 The sampler shall be operated in accordance with the specific guidance provided in the sampler manufacturer's instruction manual and in reference 2 in section 12.0 of this appendix. The general procedure given here assumes that the sampler's flow rate calibration is based on flow rates at ambient conditions (Q
9.2 Inspect each filter for pinholes, particles, and other imperfections. Establish a filter information record and assign an identification number to each filter.
9.3 Equilibrate each filter in the conditioning environment (see 7.4) for at least 24 hours.
9.4 Following equilibration, weigh each filter and record the presampling weight with the filter identification number.
9.5 Install a preweighed filter in the sampler following the instructions provided in the sampler manufacturer's instruction manual.
9.6 (a) Turn on the sampler and allow it to establish run-temperature conditions. Record the flow indicator reading and, if needed, the ambient temperature and barometric pressure. Determine the sampler flow rate (actual m
(b) Note: No onsite temperature or pressure measurements are necessary if the sampler's flow indicator does not require temperature or pressure corrections or if seasonal average temperature and average barometric pressure for the sampling site are incorporated into the sampler calibration, under section 8.2.4 of this appendix. If individual or daily temperature and pressure corrections are required, ambient temperature and barometric pressure can be obtained by on-site measurements or from a nearby weather station. Barometric pressure readings obtained from airports must be station pressure, not corrected to sea level, and may need to be corrected for differences in elevation between the sampling site and the airport.
9.7 If the flow rate is outside the acceptable range specified by the manufacturer, check for leaks, and if necessary, adjust the flow rate to the specified setpoint. Stop the sampler.
9.8 Set the timer to start and stop the sampler at appropriate times. Set the elapsed time meter to zero or record the initial meter reading.
9.9 Record the sample information (site location or identification number, sample date, filter identification number, and sampler model and serial number).
9.10 Sample for 24
9.11 Determine and record the average flow rate (Q
9.12 Carefully remove the filter from the sampler, following the sampler manufacturer's instruction manual. Touch only the outer edges of the filter.
9.13 Place the filter in a protective holder or container, e.g., petri dish, glassine envelope, or manila folder.
9.14 Record any factors such as meteorological conditions, construction activity, fires or dust storms, etc., that might be pertinent to the measurement on the filter information record.
9.15 Transport the exposed sample filter to the filter conditioning environment as soon as possible for equilibration and subsequent weighing.
9.16 Equilibrate the exposed filter in the conditioning environment for at least 24 hours under the same temperature and humidity conditions used for presampling filter equilibration (see section 9.3 of this appendix).
9.17 Immediately after equilibration, reweigh the filter and record the postsampling weight with the filter identification number.
10.0
10.1 The PM
11.0
11.1 Calculate the total volume of air sampled as:
11.2 (a) Calculate the PM
(b) Note: If more than one size fraction in the PM
12.0
1. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I, Principles. EPA-600/9-76-005, March 1976. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West St. Clair Street, Cincinnati, OH 45268.
2. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods. EPA-600/4-77-027a, May 1977. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West St. Clair Street, Cincinnati, OH 45268.
3. Clement, R.E., and F.W. Karasek. Sample Composition Changes in Sampling and Analysis of Organic Compounds in Aerosols. Int. J. Environ. Analyt. Chem., 7:109, 1979.
4. Lee, R.E., Jr., and J. Wagman. A Sampling Anomaly in the Determination of Atmospheric Sulfate Concentration. Amer. Ind. Hyg. Assoc. J., 27:266, 1966.
5. Appel, B.R., S.M. Wall, Y. Tokiwa, and M. Haik. Interference Effects in Sampling Particulate Nitrate in Ambient Air. Atmos. Environ., 13:319, 1979.
6. Coutant, R.W. Effect of Environmental Variables on Collection of Atmospheric Sulfate. Environ. Sci. Technol., 11:873, 1977.Spicer, C.W., and P. Schumacher. Interference in Sampling Atmospheric Particulate Nitrate. Atmos. Environ., 11:873, 1977.
8. Appel, B.R., Y. Tokiwa, and M. Haik. Sampling of Nitrates in Ambient Air. Atmos. Environ., 15:283, 1981.
9. Spicer, C.W., and P.M. Schumacher. Particulate Nitrate: Laboratory and Field Studies of Major Sampling Interferences. Atmos. Environ., 13:543, 1979.
10. Appel, B.R. Letter to Larry Purdue, U.S. EPA, Environmental Monitoring and Support Laboratory. March 18, 1982, Docket No. A-82-37, II-I-1.
11. Pierson, W.R., W.W. Brachaczek, T.J. Korniski, T.J. Truex, and J.W. Butler. Artifact Formation of Sulfate, Nitrate, and Hydrogen Ion on Backup Filters: Allegheny Mountain Experiment. J. Air Pollut. Control Assoc., 30:30, 1980.
12. Dunwoody, C.L. Rapid Nitrate Loss From PM
13. Harrell, R.M. Measuring the Alkalinity of Hi-Vol Air Filters. EMSL/RTP-SOP-QAD-534, October 1985. Available from the U.S. Environmental Protection Agency, EMSL/QAD, Research Triangle Park, NC 27711.
14. Smith, F., P.S. Wohlschlegel, R.S.C. Rogers, and D.J. Mulligan. Investigation of Flow Rate Calibration Procedures Associated With the High Volume Method for Determination of Suspended Particulates. EPA-600/4-78-047, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1978.
1.0
(a) This appendix explains the data handling conventions and computations necessary for determining when the annual and 24-hour primary and secondary national ambient air quality standards for PM specified in § 50.7 of this chapter are met. Particulate matter is measured in the ambient air as PM
(b) Data resulting from uncontrollable or natural events, for example structural fires or high winds, may require special consideration. In some cases, it may be appropriate to exclude these data because they could result in inappropriate values to compare with the levels of the PM standards. In other cases, it may be more appropriate to retain the data for comparison with the level of the PM standards and then allow the EPA to formulate the appropriate regulatory response. Whether to exclude, retain, or make adjustments to the data affected by uncontrollable or natural events is subject to the approval of the appropriate Regional Administrator.
(c) The terms used in this appendix are defined as follows:
98
99
(d) Sections 2.1 and 2.5 of this appendix contain data handling instructions for the option of using a spatially averaged network of monitors for the annual standard. If spatial averaging is not considered for an area, then the spatial average is equivalent to the annual average of a single site and is treated accordingly in subsequent calculations. For example, paragraph (a)(3) of section 2.1 of this appendix could be eliminated since the spatial average would be equivalent to the annual average.
2.0
2.1
(a) The annual PM
(1) Average 24-hour measurements to obtain quarterly means at each monitor.
(2) Average quarterly means to obtain annual means at each monitor.
(3) Average across designated monitoring sites to obtain an annual spatial mean for an area (this can be one site in which case the spatial mean is equal to the annual mean).
(4) Average 3 years of annual spatial means to obtain a 3-year average of spatially averaged annual means.
(b) In the case of spatial averaging, 3 years of spatial averages are required to demonstrate that the standard has been met. Designated sites with less than 3 years of data shall be included in spatial averages for those years that data completeness requirements are met. For the annual PM
(c) Situations may arise in which there are compelling reasons to retain years containing quarters which do not meet the data completeness requirement of 75 percent or the minimum number of 11 samples. The use of less than complete data is subject to the approval of the appropriate Regional Administrator.
(d) The equations for calculating the 3-year average annual mean of the PM
2.2
(a) The 24-hour PM
(b) Situations may arise in which there are compelling reasons to retain years containing quarters which do not meet the data completeness requirement. The use of less than complete data is subject to the approval of the appropriate Regional Administrator.
(c) The equations for calculating the 3-year average of the annual 98
2.3
2.4
(a) Section 58.13 of this chapter specifies the required minimum frequency of sampling
(b) For the annual PM
2.5
(a) An annual mean value for PM
(b) The following equation is then to be used for calculation of the annual mean:
(c)(1) The spatially averaged annual mean for year y is computed by first calculating the annual mean for each site designated to be included in a spatial average, x
(2) In the event that an area designated for spatial averaging has two or more sites at the same location producing data for the same time periods, the sites are averaged together before using Equation 3 by:
(d) The 3-year average of the spatially averaged annual means is calculated by using the following equation:
a. In an area designated for spatial averaging, four designated monitors recorded data in at least 1 year of a particular 3-year period. Using Equations 1 and 2, the annual means for PM
b. The data from these sites are averaged in the order described in section 2.1 of this appendix. Note that the annual mean from site #3 in year 2 and the annual mean from site #4 in year 3 do not meet the 75 percent data completeness criteria. Assuming the 38 percent data completeness represents a quarter with fewer than 11 samples, site #3 in year 2 does not meet the minimum data completeness requirement of 11 samples in each quarter. The site is therefore excluded from the calculation of the spatial mean for year 2. However, since the spatial mean for year 3 is above the level of the standard and the minimum data requirement of 11 samples in each quarter has been met, the annual mean from site #4 in year 3 is included in the calculation of the spatial mean for year 3 and in the calculation of the 3-year average. The 3-year average is rounded to 14.4
a. In an area designated for spatial averaging, six designated monitors, with two monitors at the same location (#5 and #6), recorded data in a particular 3-year period. Using Equations 1 and 2, the annual means for PM
b. The annual means for sites #5 and #6 are averaged together using Equation 4 before the spatial average is calculated using Equation 3 since they are in the same location. The 3-year mean is rounded to 12.6
a. Given data from a single monitor in an area, the calculations are as follows. Using Equations 1 and 2, the annual means for PM
b. This value is rounded to 13.3, indicating that this area meets the annual PM
2.6
(a) When the data for a particular site and year meet the data completeness requirements in section 2.2 of this appendix, calculation of the 98
(b) The 3-year average 98
(c) The 3-year average 98
a. In each year of a particular 3 year period, varying numbers of daily PM
b. Using Equation 6, the 98
c.1. Using Equation 7, the 3-year average 98
2. Therefore, this site meets the 24-hour PM
3.0
3.1
(a) The annual PM
(1) Average 24-hour measurements to obtain a quarterly mean.
(2) Average quarterly means to obtain an annual mean.
(3) Average annual means to obtain a 3-year mean.
(b) For the annual PM
(c) Situations may arise in which there are compelling reasons to retain years containing quarters which do not meet the data completeness requirement of 75 percent or the minimum number of 11 samples. The use of less than complete data is subject to the approval of the appropriate Regional Administrator.
(d) The equations for calculating the 3-year average annual mean of the PM
3.2
(a) The 24-hour PM
(b) Situations may arise in which there are compelling reasons to retain years containing quarters which do not meet the data completeness requirement. The use of less than complete data is subject to the approval of the appropriate Regional Administrator.
(c) The equation for calculating the 3-year average of the annual 99
3.3
3.4
3.5
(a) An annual arithmetic mean value for PM
(b) The following equation is then to be used for calculation of the annual mean:
(c) The 3-year average of the annual means is calculated by using the following equation:
a. Given data from a PM
b. Therefore, this site does not meet the annual PM
3.6
(a) When the data for a particular site and year meet the data completeness requirements in section 3.2 of this appendix, calculation of the 99
(b) The 3-year average 99
(c) The 3-year average 99
a. In each year of a particular 3 year period, varying numbers of PM
b. Using Equation 11, the 99
c. 1. Using Equation 12, the 3-year average 99
2. Therefore, this site meets the 24-hour PM
42 U.S.C. 7410, 7414, 7421, 7470-7479, 7491, 7492, 7601, and 7602.
42 U.S.C. 7401, 7411, 7412, 7413, 7414, 7470-7479, 7501-7508, 7601, and 7602.
As used in this part, all terms not defined herein will have the meaning given them in the Act:
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
(1) For particulate matter, sulfur oxides, carbon monoxide, volatile organic compounds (VOC) and nitrogen dioxide—
(i) Any stationary source the actual emissions of which are in excess of 90.7 metric tons (100 tons) per year of the pollutant in a region containing an area whose 1980
(ii) Any stationary source the actual emissions of which are in excess of 22.7 metric tons (25 tons) per year of the pollutant in a region containing an area whose 1980
(2) For lead or lead compounds measured as elemental lead, any stationary source that actually emits a total of 4.5 metric tons (5 tons) per year or more.
(l)
(m)
(n)
(1) Emission limitations.
(2) Federal or State emission charges or taxes or other economic incentives or disincentives.
(3) Closing or relocation of residential, commercial, or industrial facilities.
(4) Changes in schedules or methods of operation of commercial or industrial facilities or transportation systems, including, but not limited to, short-term changes made in accordance with standby plans.
(5) Periodic inspection and testing of motor vehicle emission control systems, at such time as the Administrator determines that such programs are feasible and practicable.
(6) Emission control measures applicable to in-use motor vehicles, including, but not limited to, measures such as mandatory maintenance, installation of emission control devices, and conversion to gaseous fuels.
(7) Any transportation control measure including those transportation measures listed in section 108(f) of the Clean Air Act as amended.
(8) Any variation of, or alternative to any measure delineated herein.
(9) Control or prohibition of a fuel or fuel additive used in motor vehicles, if such control or prohibition is necessary to achieve a national primary or secondary air quality standard and is approved by the Administrator under section 211(c)(4)(C) of the Act.
(o)
(1) The necessity of imposing such controls in order to attain and maintain a national ambient air quality standard;
(2) The social, environmental, and economic impact of such controls; and
(3) Alternative means of providing for attainment and maintenance of such standard. (This provision defines RACT for the purposes of § 51.341(b) only.)
(p)
(q)
(1) Date of submittal of the source's final control plan to the appropriate air pollution control agency;
(2) Date by which contracts for emission control systems or process modifications will be awarded; or date by which orders will be issued for the purchase of component parts to accomplish emission control or process modification;
(3) Date of initiation of on-site construction or installation of emission control equipment or process change;
(4) Date by which on-site construction or installation of emission control equipment or process modification is to be completed; and
(5) Date by which final compliance is to be achieved.
(r)
(s)
(1) This includes any such organic compound other than the following, which have been determined to have negligible photochemical reactivity: methane; ethane; methylene chloride (dichloromethane); 1,1,1-trichloroethane (methyl chloroform); 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113); trichlorofluoromethane (CFC-11); dichlorodifluoromethane (CFC-12); chlorodifluoromethane (HCFC-22); trifluoromethane (HFC-23); 1,2-dichloro
(i) Cyclic, branched, or linear, completely fluorinated alkanes;
(ii) Cyclic, branched, or linear, completely fluorinated ethers with no unsaturations;
(iii) Cyclic, branched, or linear, completely fluorinated tertiary amines with no unsaturations; and
(iv) Sulfur containing perfluorocarbons with no unsaturations and with sulfur bonds only to carbon and fluorine.
(2) For purposes of determining compliance with emissions limits, VOC will be measured by the test methods in the approved State implementation plan (SIP) or 40 CFR part 60, appendix A, as applicable. Where such a method also measures compounds with negligible photochemical reactivity, these negligibility-reactive compounds may be excluded as VOC if the amount of such compounds is accurately quantified, and such exclusion is approved by the enforcement authority.
(3) As a precondition to excluding these compounds as VOC or at any time thereafter, the enforcement authority may require an owner or operator to provide monitoring or testing methods and results demonstrating, to the satisfaction of the enforcement authority, the amount of negligibly-reactive compounds in the source's emissions.
(4) For purposes of Federal enforcement for a specific source, the EPA shall use the test methods specified in the applicable EPA-approved SIP, in a permit issued pursuant to a program approved or promulgated under title V of the Act, or under 40 CFR part 51, subpart I or appendix S, or under 40 CFR parts 52 or 60. The EPA shall not be bound by any State determination as to appropriate methods for testing or monitoring negligibly-reactive compounds if such determination is not reflected in any of the above provisions.
(t)-(w) [Reserved]
(x)
(y)
(z)
(aa)
(bb)
(cc)
(dd)
(ee)
(ff)
(gg)
(hh)(1)
(i) Using that portion of a stack which exceeds good engineering practice stack height:
(ii) Varying the rate of emission of a pollutant according to atmospheric conditions or ambient concentrations of that pollutant; or
(iii) Increasing final exhaust gas plume rise by manipulating source process parameters, exhaust gas parameters, stack parameters, or combining exhaust gases from several existing stacks into one stack; or other selective handling of exhaust gas streams so as to increase the exhaust gas plume rise.
(2) The preceding sentence does not include:
(i) The reheating of a gas stream, following use of a pollution control system, for the purpose of returning the gas to the temperature at which it was originally discharged from the facility generating the gas stream;
(ii) The merging of exhaust gas streams where:
(A) The source owner or operator demonstrates that the facility was originally designed and constructed with such merged gas streams;
(B) After July 8, 1985 such merging is part of a change in operation at the facility that includes the installation of pollution controls and is accompanied by a net reduction in the allowable emissions of a pollutant. This exclusion from the definition of
(C) Before July 8, 1985, such merging was part of a change in operation at the facility that included the installation of emissions control equipment or was carried out for sound economic or engineering reasons. Where there was an increase in the emission limitation or, in the event that no emission limitation was in existence prior to the merging, an increase in the quantity of pollutants actually emitted prior to the merging, the reviewing agency shall presume that merging was significantly motivated by an intent to gain emissions credit for greater dispersion. Absent a demonstration by the source owner or operator that merging was not significantly motivated by such intent, the reviewing agency shall deny credit for the effects of such merging in calculating the allowable emissions for the source;
(iii) Smoke management in agricultural or silvicultural prescribed burning programs;
(iv) Episodic restrictions on residential woodburning and open burning; or
(v) Techniques under § 51.100(hh)(1)(iii) which increase final exhaust gas plume rise where the resulting allowable emissions of sulfur dioxide from the facility do not exceed 5,000 tons per year.
(ii)
(1) 65 meters, measured from the ground-level elevation at the base of the stack:
(2)(i) For stacks in existence on January 12, 1979, and for which the owner or operator had obtained all applicable permits or approvals required under 40 CFR parts 51 and 52.
(ii) For all other stacks,
(3) The height demonstrated by a fluid model or a field study approved by the EPA State or local control agency, which ensures that the emissions from a stack do not result in excessive concentrations of any air pollutant as a result of atmospheric downwash, wakes, or eddy effects created by the source itself, nearby structures or nearby terrain features.
(jj)
(1) For purposes of applying the formulae provided in § 51.100(ii)(2) means that distance up to five times the lesser of the height or the width dimension of a structure, but not greater than 0.8 km (
(2) For conducting demonstrations under § 51.100(ii)(3) means not greater than 0.8 km (
(kk)
(1) For sources seeking credit for stack height exceeding that established under § 51.100(ii)(2) a maximum ground-level concentration due to emissions from a stack due in whole or part to downwash, wakes, and eddy effects produced by nearby structures or nearby terrain features which individually is at least 40 percent in excess of the maximum concentration experienced in the absence of such downwash, wakes, or eddy effects and which contributes to a total concentration due to emissions from all sources that is greater than an ambient air quality standard. For sources subject to the prevention of significant deterioration program (40 CFR 51.166 and 52.21), an excessive concentration alternatively means a maximum ground-level concentration due to emissions from a stack due in whole or part to downwash, wakes, or eddy effects produced by nearby structures or nearby terrain features which individually is at least 40 percent in excess of the maximum concentration experienced in the absence of such downwash, wakes, or eddy effects and greater than a prevention of significant deterioration increment. The allowable emission rate to be used in making demonstrations under this part shall be prescribed by the new source performance standard that is applicable to the source category unless the owner or operator demonstrates that this emission
(2) For sources seeking credit after October 11, 1983, for increases in existing stack heights up to the heights established under § 51.100(ii)(2), either (i) a maximum ground-level concentration due in whole or part to downwash, wakes or eddy effects as provided in paragraph (kk)(1) of this section, except that the emission rate specified by any applicable State implementation plan (or, in the absence of such a limit, the actual emission rate) shall be used, or (ii) the actual presence of a local nuisance caused by the existing stack, as determined by the authority administering the State implementation plan; and
(3) For sources seeking credit after January 12, 1979 for a stack height determined under § 51.100(ii)(2) where the authority administering the State implementation plan requires the use of a field study or fluid model to verify GEP stack height, for sources seeking stack height credit after November 9, 1984 based on the aerodynamic influence of cooling towers, and for sources seeking stack height credit after December 31, 1970 based on the aerodynamic influence of structures not adequately represented by the equations in § 51.100(ii)(2), a maximum ground-level concentration due in whole or part to downwash, wakes or eddy effects that is at least 40 percent in excess of the maximum concentration experienced in the absence of such downwash, wakes, or eddy effects.
(ll)-(mm) [Reserved]
(nn) Intermittent control system (ICS) means a dispersion technique which varies the rate at which pollutants are emitted to the atmosphere according to meteorological conditions and/or ambient concentrations of the pollutant, in order to prevent ground-level concentrations in excess of applicable ambient air quality standards. Such a dispersion technique is an ICS whether used alone, used with other dispersion techniques, or used as a supplement to continuous emission controls (i.e., used as a supplemental control system).
(oo)
(pp)
(qq)
(rr)
(ss)
Nothing in this part will be construed in any manner:
(a) To encourage a State to prepare, adopt, or submit a plan which does not provide for the protection and enhancement of air quality so as to promote the public health and welfare and productive capacity.
(b) To encourage a State to adopt any particular control strategy without taking into consideration the cost-effectiveness of such control strategy
(c) To preclude a State from employing techniques other than those specified in this part for purposes of estimating air quality or demonstrating the adequacy of a control strategy, provided that such other techniques are shown to be adequate and appropriate for such purposes.
(d) To encourage a State to prepare, adopt, or submit a plan without taking into consideration the social and economic impact of the control strategy set forth in such plan, including, but not limited to, impact on availability of fuels, energy, transportation, and employment.
(e) To preclude a State from preparing, adopting, or submitting a plan which provides for attainment and maintenance of a national standard through the application of a control strategy not specifically identified or described in this part.
(f) To preclude a State or political subdivision thereof from adopting or enforcing any emission limitations or other measures or combinations thereof to attain and maintain air quality better than that required by a national standard.
(g) To encourage a State to adopt a control strategy uniformly applicable throughout a region unless there is no satisfactory alternative way of providing for attainment and maintenance of a national standard throughout such region.
(a) Except as otherwise provided in paragraph (c) of this section, States must conduct one or more public hearings on the following prior to adoption and submission to EPA of:
(1) Any plan or revision of it required by § 51.104(a).
(2) Any individual compliance schedule under (§ 51.260).
(3) Any revision under § 51.104(d).
(b) Separate hearings may be held for plans to implement primary and secondary standards.
(c) No hearing will be required for any change to an increment of progress in an approved individual compliance schedule unless such change is likely to cause the source to be unable to comply with the final compliance date in the schedule. The requirements of §§ 51.104 and 51.105 will be applicable to such schedules, however.
(d) Any hearing required by paragraph (a) of this section will be held only after reasonable notice, which will be considered to include, at least 30 days prior to the date of such hearing(s):
(1) Notice given to the public by prominent advertisement in the area affected announcing the date(s), time(s), and place(s) of such hearing(s);
(2) Availability of each proposed plan or revision for public inspection in at least one location in each region to which it will apply, and the availability of each compliance schedule for public inspection in at least one location in the region in which the affected source is located;
(3) Notification to the Administrator (through the appropriate Regional Office);
(4) Notification to each local air pollution control agency which will be significantly impacted by such plan, schedule or revision;
(5) In the case of an interstate region, notification to any other States included, in whole or in part, in the regions which are significantly impacted by such plan or schedule or revision.
(6) In the case of hearings on AQMA plans:
(i) Notification to the chief executives of affected local governments, planning agencies, transportation agencies, environmental control agencies, economic development agencies, and any other affected States, and
(ii) Public notice of alternative analysis and plan development procedures approved under § 51.63.
(e) The State must prepare and retain, for inspection by the Administrator upon request, a record of each hearing. The record must contain, as a minimum, a list of witnesses together with the text of each presentation.
(f) The State must submit with the plan, revision, or schedule a certification that the hearing required by paragraph (a) of this section was held in accordance with the notice required by paragraph (d) of this section.
(g) Upon written application by a State agency (through the appropriate Regional Office), the Administrator may approve State procedures for public hearings. The following criteria apply:
(1) Procedures approved under this section shall be deemed to satisfy the requirement of this part regarding public hearings.
(2) Procedures different from this part may be approved if they—
(i) Ensure public participation in matters for which hearings are required; and
(ii) Provide adequate public notification of the opportunity to participate.
(3) The Administrator may impose any conditions on approval he or she deems necessary.
(a) The State makes an official plan submission to EPA only when the submission conforms to the requirements of appendix V to this part, and the State delivers five copies of the plan to the appropriate Regional Office, with a letter giving notice of such action.
(b) Upon request of a State, the Administrator will provide preliminary review of a plan or portion thereof submitted in advance of the date such plan is due. Such requests must be made in writing to the appropriate Regional Office and must be accompanied by five copies of the materials to be reviewed. Requests for preliminary review do not relieve a State of the responsibility of adopting and submitting plans in accordance with prescribed due dates.
(a) States may revise the plan from time to time consistent with the requirements applicable to implementation plans under this part.
(b) The States must submit any revision of any regulation or any compliance schedule under paragraph (c) of this section to the Administrator no later than 60 days after its adoption.
(c) EPA will approve revisions only after applicable hearing requirements of § 51.102 have been satisfied.
(d) In order for a variance to be considered for approval as a revision to the State implementation plan, the State must submit it in accordance with the requirements of this section.
Revisions of a plan, or any portion thereof, will not be considered part of an applicable plan until such revisions have been approved by the Administrator in accordance with this part.
(a) Each plan providing for the attainment of a primary or secondary standard must specify the projected attainment date.
(b)-(f) [Reserved]
(g) During developing of the plan, EPA encourages States to identify alternative control strategies, as well as the costs and benefits of each such alternative for attainment or maintenance of the national standard.
Each plan must set forth a control strategy which includes the following:
(a) A description of enforcement methods including, but not limited to:
(1) Procedures for monitoring compliance with each of the selected control measures,
(2) Procedures for handling violations, and
(3) A designation of agency responsibility for enforcement of implementation.
(b) [Reserved]
(a) Each plan must demonstrate that the measures, rules, and regulations contained in it are adequate to provide for the timely attainment and maintenance of the national standard that it implements.
(1) The adequacy of a control strategy shall be demonstrated by means of applicable air quality models, data bases, and other requirements specified in appendix W of this part (Guideline on Air Quality Models).
(2) Where an air quality model specified in appendix W of this part (Guideline on Air Quality Models) is inappropriate, the model may be modified or another model substituted. Such a modification or substitution of a model may be made on a case-by-case basis or, where appropriate, on a generic basis for a specific State program. Written approval of the Administrator must be obtained for any modification or substitution. In addition, use of a modified or substituted model must be subject to notice and opportunity for public comment under procedures set forth in § 51.102.
(b) The demonstration must include the following:
(1) A summary of the computations, assumptions, and judgments used to determine the degree of reduction of emissions (or reductions in the growth of emissions) that will result from the implementation of the control strategy.
(2) A presentation of emission levels expected to result from implementation of each measure of the control strategy.
(3) A presentation of the air quality levels expected to result from implementation of the overall control strategy presented either in tabular form or as an isopleth map showing expected maximum pollutant concentrations.
(4) A description of the dispersion models used to project air quality and to evaluate control strategies.
(5) For interstate regions, the analysis from each constituent State must, where practicable, be based upon the same regional emission inventory and air quality baseline.
(a) Except for lead, each plan must contain a detailed inventory of emissions from point and area sources. Lead requirements are specified in § 51.117. The inventory must be based upon measured emissions or, where measured emissions are not available, documented emission factors.
(b) Each plan must contain a summary of emission levels projected to result from application of the new control strategy.
(c) Each plan must identify the sources of the data used in the projection of emissions.
(a) Each plan must contain a summary of data showing existing air quality.
(b) Each plan must:
(1) Contain a summary of air quality concentrations expected to result from application of the control strategy, and
(2) Identify and describe the dispersion model, other air quality model, or receptor model used.
(c) Actual measurements of air quality must be used where available if made by methods specified in appendix C to part 58 of this chapter. Estimated air quality using appropriate modeling techniques may be used to supplement measurements.
(d) For purposes of developing a control strategy, background concentration shall be taken into consideration with respect to particulate matter. As used in this subpart, background concentration is that portion of the measured ambient levels that cannot be reduced by controlling emissions from man-made sources.
(e) In developing an ozone control strategy for a particular area, background ozone concentrations and ozone transported into an area must be considered. States may assume that the ozone standard will be attained in upwind areas.
(a) The State must retain all detailed data and calculations used in the preparation of each plan or each plan revision, and make them available for public inspection and submit them to the Administrator at his request.
(b) The detailed data and calculations used in the preparation of plan revisions are not considered a part of the plan.
(c) Each plan must provide for public availability of emission data reported by source owners or operators or otherwise obtained by a State or local agency. Such emission data must be correlated with applicable emission limitations or other measures. As used in this paragraph,
In addition to other requirements in §§ 51.100 through 51.116 the following requirements apply to lead. To the extent they conflict, there requirements are controlling over those of the proceeding sections.
(a)
(1) Areas in the vicinity of the following point sources of lead: Primary lead smelters, Secondary lead smelters, Primary copper smelters, Lead gasoline additive plants, Lead-acid storage battery manufacturing plants that produce 2,000 or more batteries per day. Any other stationary source that actually emits 25 or more tons per year of lead or lead compounds measured as elemental lead.
(2) Any other area that has lead air concentrations in excess of the national ambient air quality standard concentration for lead, measured since January 1, 1974.
(b)
(c)
(2) For each point source listed in § 51.117(a), that plan must employ an atmospheric dispersion model for demonstration of attainment, consistent with requirements contained in § 51.112(a).
(3) For each area in the vicinity of an air quality monitor that has recorded lead concentrations in excess of the lead national standard concentration, the plan must employ the modified rollback model as a minimum, but may use an atmospheric dispersion model if desired for the demonstration of attainment, consistent with requirements contained in § 51.112(a).
(d)
(2) The data must be submitted in accordance with the procedures and data forms specified in Chapter 3.4.0 of the “AEROS User's Manual” concerning storage and retrieval of aerometric data (SAROAD) except where the Regional Administrator waives this requirement.
(3) If additional lead air quality data are desired to determine lead air concentrations in areas suspected of exceeding the lead national ambient air quality standard, the plan may include data from any previously collected filters from particulate matter high volume samplers. In determining the lead content of the filters for control strategy demonstration purposes, a State may use, in addition to the reference
(e)
(2) Each State must submit lead emissions data to the appropriate EPA Regional Office with the original plan. The submission must be made with the plan, but not as part of the plan, and must include emissions data and information related to point and area source emissions. The emission data and information should include the -information identified in the Hazard-ous and Trace Emissions System (HATREMS) point source coding forms for all point sources and the area source coding forms for all sources that are not point sources, but need not necessarily be in the format of those forms.
(a) The plan must provide that the degree of emission limitation required of any source for control of any air pollutant must not be affected by so much of any source's stack height that exceeds good engineering practice or by any other dispersion technique, except as provided in § 51.118(b). The plan must provide that before a State submits to EPA a new or revised emission limitation that is based on a good engineering practice stack height that exceeds the height allowed by § 51.100(ii) (1) or (2), the State must notify the public of the availabilty of the demonstration study and must provide opportunity for a public hearing on it. This section does not require the plan to restrict, in any manner, the actual stack height of any source.
(b) The provisions of § 51.118(a) shall not apply to (1) stack heights in existence, or dispersion techniques implemented on or before December 31, 1970, except where pollutants are being emitted from such stacks or using such dispersion techniques by sources, as defined in section 111(a)(3) of the Clean Air Act, which were constructed, or reconstructed, or for which major modifications, as defined in §§ 51.165(a)(1)(v)(A), 51.166(b)(2)(i) and 52.21(b)(2)(i), were carried out after December 31, 1970; or (2) coal-fired steam electric generating units subject to the provisions of section 118 of the Clean Air Act, which commenced operation before July 1, 1957, and whose stacks were construced under a construction contract awarded before February 8, 1974.
(a) The use of an intermittent control system (ICS) may be taken into account in establishing an emission limitation for a pollutant under a State implementation plan, provided:
(1) The ICS was implemented before December 31, 1970, according to the criteria specified in § 51.119(b).
(2) The extent to which the ICS is taken into account is limited to reflect emission levels and associated ambient pollutant concentrations that would result if the ICS was the same as it was before December 31, 1970, and was operated as specified by the operating system of the ICS before December 31, 1970.
(3) The plan allows the ICS to compensate only for emissions from a source for which the ICS was implemented before December 31, 1970, and, in the event the source has been modified, only to the extent the emissions correspond to the maximum capacity of the source before December 31, 1970. For purposes of this paragraph, a source for which the ICS was implemented is any particular structure or equipment the emissions from which were subject to the ICS operating procedures.
(4) The plan requires the continued operation of any constant pollution control system which was in use before December 31, 1970, or the equivalent of that system.
(5) The plan clearly defines the emission limits affected by the ICS and the manner in which the ICS is taken into account in establishing those limits.
(6) The plan contains requirements for the operation and maintenance of the qualifying ICS which, together with the emission limitations and any
(i) Requirements that a source owner or operator continuously operate and maintain the components of the ICS specified at § 51.119(b)(3) (ii)-(iv) in a manner which assures that the ICS is at least as effective as it was before December 31, 1970. The air quality monitors and meteorological instrumentation specified at § 51.119(b) may be operated by a local authority or other entity provided the source has ready access to the data from the monitors and instrumentation.
(ii) Requirements which specify the circumstances under which, the extent to which, and the procedures through which, emissions shall be curtailed through the activation of ICS.
(iii) Requirements for recordkeeping which require the owner or operator of the source to keep, for periods of at least 3 years, records of measured ambient air quality data, meteorological information acquired, and production data relating to those processes affected by the ICS.
(iv) Requirements for reporting which require the owner or operator of the source to notify the State and EPA within 30 days of a NAAQS violation pertaining to the pollutant affected by the ICS.
(7) Nothing in this paragraph affects the applicability of any new source review requirements or new source performance standards contained in the Clean Air Act or 40 CFR subchapter C. Nothing in this paragraph precludes a State from taking an ICS into account in establishing emission limitations to any extent less than permitted by this paragraph.
(b) An intermittent control system (ICS) may be considered implemented for a pollutant before December 31, 1970, if the following criteria are met:
(1) The ICS must have been established and operational with respect to that pollutant prior to December 31, 1970, and reductions in emissions of that pollutant must have occurred when warranted by meteorological and ambient monitoring data.
(2) The ICS must have been designed and operated to meet an air quality objective for that pollutant such as an air quality level or standard.
(3) The ICS must, at a minimum, have included the following components prior to December 31, 1970:
(i)
(ii)
(iii)
(iv)
(4) Documentation sufficient to support the claim that the ICS met the criteria listed in this paragraph must be provided. Such documentation may include affidavits or other documentation.
(a) The EPA Administrator finds that the State Implementation Plans (SIPs)
(b) If a SIP revision is required under paragraph (a) of this section, it must contain the OTC LEV program described in paragraph (c) of this section unless the State adopts and submits to EPA, as a SIP revision, other emission-reduction measures sufficient to meet the requirements of paragraph (d) of this section. If a State adopts and submits to EPA, as a SIP revision, other emission-reduction measures pursuant to paragraph (d) of this section, then for purposes of determining whether such a SIP revision is complete within the meaning of section 110(k)(1) (and hence is eligible at least for consideration to be approved as satisfying paragraph (d) of this section), such a SIP revision must contain other adopted emission-reduction measures that, together with the identified potentially broadly practicable measures, achieve at least the minimum level of emission reductions that could potentially satisfy the requirements of paragraph (d) of this section. All such measures must be fully adopted and enforceable.
(c) The OTC LEV program is a program adopted pursuant to section 177 of the Clean Air Act.
(1) The OTC LEV program shall contain the following elements:
(i) It shall apply to all new 1999 and later model year passenger cars and light-duty trucks (0-5750 pounds loaded vehicle weight), as defined in Title 13, California Code of Regulations, section 1900(b)(11) and (b)(8), respectively, that are sold, imported, delivered, purchased, leased, rented, acquired, received, or registered in any area of the State that is in the Northeast Ozone Transport Region as of December 19, 1994.
(ii) All vehicles to which the OTC LEV program is applicable shall be required to have a certificate from the California Air Resources Board (CARB) affirming compliance with California standards.
(iii) All vehicles to which this LEV program is applicable shall be required to meet the mass emission standards for Non-Methane Organic Gases (NMOG), Carbon Monoxide (CO), Oxides of Nitrogen (NO
(iv) All manufacturers of vehicles subject to the OTC LEV program shall be required to meet the fleet average NMOG exhaust emission values for production and delivery for sale of their passenger cars, light-duty trucks 0-3750 pounds loaded vehicle weight, and light-duty trucks 3751-5750 pounds loaded vehicle weight specified in Title 13, California Code of Regulations, section 1960.1(g)(2) for each model year beginning in 1999. A State may determine
(v) All manufacturers shall be allowed to average, bank and trade credits in the same manner as allowed under the program specified in Title 13, California Code of Regulations, section 1960.1(g)(2) footnote 7 for each model year beginning in 1999. States may account for credits banked by manufacturers in California or New York in years immediately preceding model year 1999, in a manner consistent with California banking and discounting procedures.
(vi) The provisions for small volume manufacturers and intermediate volume manufacturers, as applied by Title 13, California Code of Regulations to California's LEV program, shall apply. Those manufacturers defined as small volume manufacturers and intermediate volume manufacturers in California under California's regulations shall be considered small volume manufacturers and intermediate volume manufacturers under this program.
(vii) The provisions for hybrid electric vehicles (HEVs), as defined in Title 13 California Code of Regulations, section 1960.1, shall apply for purposes of calculating fleet average NMOG values.
(viii) The provisions for fuel-flexible vehicles and dual-fuel vehicles specified in Title 13, California Code of Regulations, section 1960.1(g)(1) footnote 4 shall apply.
(ix) The provisions for reactivity adjustment factors, as defined by Title 13, California Code of Regulations, shall apply.
(x) The aforementioned State OTC LEV standards shall be identical to the aforementioned California standards as such standards exist on December 19, 1994.
(xi) All States' OTC LEV programs must contain any other provisions of California's LEV program specified in Title 13, California Code of Regulations necessary to comply with section 177 of the Clean Air Act.
(2) States are not required to include the mandate for production of ZEVs specified in Title 13, California Code of Regulations, section 1960.1(g)(2) footnote 9.
(3) Except as specified elsewhere in this section, States may implement the OTC LEV program in any manner consistent with the Act that does not decrease the emissions reductions or jeopardize the effectiveness of the program.
(d) The SIP revision that paragraph (b) of this section describes as an alternative to the OTC LEV program described in paragraph (c) of this section must contain a set of State-adopted measures that provides at least the following amount of emission reductions in time to bring serious ozone nonattainment areas into attainment by their 1999 attainment date:
(1) Reductions at least equal to the difference between:
(i) The nitrogen oxides (NO
(ii) A reduction in NO
(2) Reductions at least equal to the difference between:
(i) The VOC emission reductions from the 1990 statewide emissions inventory achievable through implementation of all of the Clean Air Act-mandated and potentially broadly practicable control measures in all portions of the State in, or near and upwind of, any of the serious or severe ozone nonattainment areas lying in the series of such areas running northeast from the Washington, DC, ozone nonattainment area to and including the Portsmouth, New Hampshire ozone nonattainment area; and
(ii) A reduction in VOC emissions from the 1990 emissions inventory in
(a)(1) The Administrator finds that the State implementation plan (SIP) for each jurisdiction listed in paragraph (c) of this section is substantially inadequate to comply with the requirements of section 110(a)(2)(D)(i)(I) of the Clean Air Act (CAA), 42 U.S.C. 7410(a)(2)(D)(i)(I), because the SIP does not include adequate provisions to prohibit sources and other activities from emitting nitrogen oxides (“NO
(2) Under section 110(a)(1) of the CAA, 42 U.S.C. 7410(a)(1), the Administrator determines that each jurisdiction listed in paragraph (c) of this section must submit a SIP revision to comply with the requirements of section 110(a)(2)(D)(i)(I), 42 U.S.C. 7410(a)(2)(D)(i)(I), through the adoption of adequate provisions prohibiting sources and other activities from emitting NO
(b)(1) For each jurisdiction listed in paragraph (c) of this section, the SIP revision required under paragraph (a) of this section will contain adequate provisions, for purposes of complying with section 110(a)(2)(D)(i)(I) of the CAA, 42 U.S.C. 7410(a)(2)(D)(i)(I), only if the SIP revision:
(i) Contains control measures adequate to prohibit emissions of NO
(ii) Requires full implementation of all such control measures by no later than May 1, 2003, and
(iii) Meets the other requirements of this section. The SIP revision's compliance with the requirement of paragraph (b)(1)(i) of this section shall be considered compliance with the jurisdiction's budget for purposes of this section.
(2) The requirements of paragraph (b)(1)(i) of this section shall be deemed satisfied, for the portion of the budget covered by an interstate trading program, if the SIP revision:
(i) Contains provisions for an interstate trading program that EPA determines will, in conjunction with interstate trading programs for one or more other jurisdictions, prohibit NO
(ii) Conforms to the following criteria:
(A) Emissions reductions used to demonstrate compliance with the revision must occur during the ozone season.
(B) Emissions reductions occurring prior to the year 2003 may be used by a source to demonstrate compliance with the SIP revision for the 2003 and 2004 ozone seasons, provided the SIP's provisions regarding such use comply with the requirements of paragraph (e)(3) of this section.
(C) Emissions reduction credits or emissions allowances held by a source or other person following the 2003 ozone season or any ozone season thereafter that are not required to demonstrate compliance with the SIP for the relevant ozone season may be banked and used to demonstrate compliance with the SIP in a subsequent ozone season.
(D) Early reductions created according to the provisions in paragraph (b)(2)(ii)(B) of this section and used in the 2003 ozone season are not subject to the flow control provisions set forth in paragraph (b)(2)(ii)(E) of this section.
(E) Starting with the 2004 ozone season, the SIP shall include provisions to limit the use of banked emissions reduction credits or emissions allowances beyond a predetermined amount as calculated by one of the following approaches:
(
(
(
(
(
(
(c) The following jurisdictions (hereinafter referred to as “States”) are subject to the requirements of this section: Alabama, Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Massachusetts, Michigan, Missouri, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Virginia, West Virginia, Wisconsin, and the District of Columbia.
(d)(1) The SIP submissions required under paragraph (a) of this section must be submitted to EPA by no later than September 30, 1999.
(2) The State makes an official submission of its SIP revision to EPA only when:
(i) The submission conforms to the requirements of appendix V to this part; and
(ii) The State delivers five copies of the plan to the appropriate Regional Office, with a letter giving notice of such action.
(e)(1) The NO
(2) The State-by-State amounts of the NO
(3)(i) Notwithstanding the State's obligation to comply with the budgets set forth in paragraph (e)(2) of this section, a SIP revision may allow sources required by the revision to implement NO
(ii) A source may not use credit from the compliance supplement pool to demonstrate compliance after the 2004 ozone season.
(iii) The State-by-State amounts of the compliance supplement pool are as follows:
(iv) The SIP revision may provide for the distribution of the compliance supplement pool to sources that are required to implement control measures using one or both of the following two mechanisms:
(A) The State may issue some or all of the compliance supplement pool to sources that implement emissions reductions during the ozone season beyond all applicable requirements in years prior to the year 2003 according to the following provisions:
(
(
(
(B) The State may issue some or all of the compliance supplement pool to sources that demonstrate a need for an extension of the May 1, 2003 compliance deadline according to the following provisions:
(
(
(
(
(
(
(
(
(4) If, no later than February 22, 1999, any member of the public requests revisions to the source-specific data and vehicle miles traveled (VMT) and nonroad mobile growth rates, VMT distribution by vehicle class, average speed by roadway type, inspection and maintenance program parameters, and other input parameters used to establish the State budgets set forth in paragraph (e)(2) of this section or the 2007 baseline sub-inventory information set forth in paragraph (g)(2)(ii) of this section, then EPA will act on that request no later than April 23, 1999 provided:
(i) The request is submitted in electronic format;
(ii) Information is provided to corroborate and justify the need for the requested modification;
(iii) The request includes the following data information regarding any electricity-generating source at issue:
(A) Federal Information Placement System (FIPS) State Code;
(B) FIPS County Code;
(C) Plant name;
(D) Plant ID numbers (ORIS code preferred, State agency tracking number also or otherwise);
(E) Unit ID numbers (a unit is a boiler or other combustion device);
(F) Unit type;
(G) Primary fuel on a heat input basis;
(H) Maximum rated heat input capacity of unit;
(I) Nameplate capacity of the largest generator the unit serves;
(J) Ozone season heat inputs for the years 1995 and 1996;
(K) 1996 (or most recent) average NO
(L) Latitude and longitude coordinates;
(M) Stack parameter information ;
(N) Operating parameter information;
(O) Identification of specific change to the inventory; and
(P) Reason for the change;
(iv) The request includes the following data information regarding any non-electricity generating point source at issue:
(A) FIPS State Code;
(B) FIPS County Code;
(C) Plant name;
(D) Facility primary standard industrial classification code (SIC);
(E) Plant ID numbers (NEDS, AIRS/AFS, and State agency tracking number also or otherwise);
(F) Unit ID numbers (a unit is a boiler or other combustion device);
(G) Primary source classification code (SCC);
(H) Maximum rated heat input capacity of unit;
(I) 1995 ozone season or typical ozone season daily NO
(J) 1995 existing NO
(K) Latitude and longitude coordinates;
(L) Stack parameter information;
(M) Operating parameter information;
(N) Identification of specific change to the inventory; and
(O) Reason for the change;
(v) The request includes the following data information regarding any stationary area source or nonroad mobile source at issue:
(A) FIPS State Code;
(B) FIPS County Code;
(C) Primary source classification code (SCC);
(D) 1995 ozone season or typical ozone season daily NO
(E) 1995 existing NO
(F) Identification of specific change to the inventory; and
(G) Reason for the change;
(vi) The request includes the following data information regarding any highway mobile source at issue:
(A) FIPS State Code;
(B) FIPS County Code;
(C) Primary source classification code (SCC) or vehicle type;
(D) 1995 ozone season or typical ozone season daily vehicle miles traveled (VMT);
(E) 1995 existing NO
(F) identification of specific change to the inventory; and
(G) reason for the change.
(f) Each SIP revision must set forth control measures to meet the NO
(1) A description of enforcement methods including, but not limited to:
(i) Procedures for monitoring compliance with each of the selected control measures;
(ii) Procedures for handling violations; and
(iii) A designation of agency responsibility for enforcement of implementation.
(2) Should a State elect to impose control measures on fossil fuel-fired NO
(i)(A) Impose a NO
(B) Impose a NO
(C) Impose any other regulatory requirement which the State has demonstrated to EPA provides equivalent or greater assurance than options in paragraphs (f)(2)(i)(A) or (f)(2)(i)(B) of this section that the State will comply with its NO
(ii) Impose enforceable mechanisms, in accordance with paragraphs (b)(1) (i) and (ii) of this section, to assure that collectively all such sources, including new or modified units, will not exceed in the 2007 ozone season the total NO
(3) For purposes of paragraph (f)(2) of this section, the term “fossil fuel-fired” means, with regard to a NO
(i) The combustion of fossil fuel, alone or in combination with any other fuel, where fossil fuel actually combusted comprises more than 50 percent of the annual heat input on a Btu basis during any year starting in 1995 or, if a NO
(ii) The combustion of fossil fuel, alone or in combination with any other fuel, where fossil fuel is projected to comprise more than 50 percent of the
(g)(1) Each SIP revision must demonstrate that the control measures contained in it are adequate to provide for the timely compliance with the State's NO
(2) The demonstration must include the following:
(i) Each revision must contain a detailed baseline inventory of NO
(ii) The base year 2007 NO
(iii) Each revision must contain a summary of NO
(iv) Each revision must identify the sources of the data used in the projection of emissions.
(h) Each revision must comply with § 51.116 of this part (regarding data availability).
(i) Each revision must provide for monitoring the status of compliance with any control measures adopted to meet the NO
(1) The revision must provide for legally enforceable procedures for requiring owners or operators of stationary sources to maintain records of and periodically report to the State:
(i) Information on the amount of NO
(ii) Other information as may be necessary to enable the State to determine whether the sources are in compliance with applicable portions of the control measures;
(2) The revision must comply with § 51.212 of this part (regarding testing, inspection, enforcement, and complaints);
(3) If the revision contains any transportation control measures, then the revision must comply with § 51.213 of this part (regarding transportation control measures);
(4) If the revision contains measures to control fossil fuel-fired NO
(5) For purposes of paragraph (i)(4) of this section, the term “fossil fuel-fired” means, with regard to a NO
(i) The combustion of fossil fuel, alone or in combination with any other fuel, where fossil fuel actually combusted comprises more than 50 percent of the annual heat input on a Btu basis during any year starting in 1995 or, if a NO
(ii) The combustion of fossil fuel, alone or in combination with any other fuel, where fossil fuel is projected to comprise more than 50 percent of the annual heat input on a Btu basis during any year, provided that the NO
(j) Each revision must show that the State has legal authority to carry out the revision, including authority to:
(1) Adopt emissions standards and limitations and any other measures necessary for attainment and maintenance of the State's NO
(2) Enforce applicable laws, regulations, and standards, and seek injunctive relief;
(3) Obtain information necessary to determine whether air pollution sources are in compliance with applicable laws, regulations, and standards, including authority to require recordkeeping and to make inspections and conduct tests of air pollution sources;
(4) Require owners or operators of stationary sources to install, maintain, and use emissions monitoring devices and to make periodic reports to the State on the nature and amounts of emissions from such stationary sources; also authority for the State to make such data available to the public as reported and as correlated with any applicable emissions standards or limitations.
(k)(1) The provisions of law or regulation which the State determines provide the authorities required under this section must be specifically identified, and copies of such laws or regulations must be submitted with the SIP revision.
(2) Legal authority adequate to fulfill the requirements of paragraphs (j)(3) and (4) of this section may be delegated to the State under section 114 of the CAA.
(l)(1) A revision may assign legal authority to local agencies in accordance with § 51.232 of this part.
(2) Each revision must comply with § 51.240 of this part (regarding general plan requirements).
(m) Each revision must comply with § 51.280 of this part (regarding resources).
(n) For purposes of the SIP revisions required by this section, EPA may make a finding as applicable under section 179(a)(1)-(4) of the CAA, 42 U.S.C. 7509(a)(1)-(4), starting the sanctions process set forth in section 179(a) of the
(o) Each revision must provide for State compliance with the reporting requirements set forth in § 51.122 of this part.
(p)(1) Notwithstanding any other provision of this section, if a State adopts regulations substantively identical to 40 CFR part 96 (the model NO
(i) The State has the legal authority to take such action and to implement its responsibilities under such regulations, and
(ii) The SIP revision accurately reflects the NO
(2) If a State adopts an emissions trading program that differs substantively from 40 CFR part 96 in only the following respects, then such portion of the State's SIP revision is approved as set forth in paragraph (p)(1) of this section:
(i) The State may expand the applicability provisions of the trading program to include units (as defined in 40 CFR 96.2) that are smaller than the size criteria thresholds set forth in 40 CFR 96.4(a);
(ii) The State may decline to adopt the exemption provisions set forth in 40 CFR 96.4(b);
(iii) The State may decline to adopt the opt-in provisions set forth in subpart I of 40 CFR part 96;
(iv) The State may decline to adopt the allocation provisions set forth in subpart E of 40 CFR part 96 and may instead adopt any methodology for allocating NO
(A) The State's methodology does not allow the State to allocate NO
(B) The State's methodology conforms with the timing requirements for submission of allocations to the Administrator set forth in 40 CFR 96.41; and
(v) The State may decline to adopt the early reduction credit provisions set forth in 40 CFR 96.55(c) and may instead adopt any methodology for issuing credit from the State's compliance supplement pool that complies with paragraph (e)(3) of this section.
(3) If a State adopts an emissions trading program that differs substantively from 40 CFR part 96 other than as set forth in paragraph (p)(2) of this section, then such portion of the State's SIP revision is not automatically approved as set forth in paragraph (p)(1) of this section but will be reviewed by the Administrator for approvability in accordance with the other provisions of this section.
(a) For its transport SIP revision under § 51.121 of this part, each State must submit to EPA NO
(b) Each revision must provide for periodic reporting by the State of NO
(1)
(i) The State must report to EPA emissions data from all NO
(ii) If sources report NO
(2)
(3)
(4) The data availability requirements in § 51.116 of this part must be followed for all data submitted to meet the requirements of paragraphs (b)(1),(2) and (3) of this section.
(c) The data reported in paragraph (b) of this section for stationary point sources must meet the following minimum criteria:
(1) For annual data reporting purposes the data must include the following minimum elements:
(i) Inventory year.
(ii) State Federal Information Placement System code.
(iii) County Federal Information Placement System code.
(iv) Federal ID code (plant).
(v) Federal ID code (point).
(vi) Federal ID code (process).
(vii) Federal ID code (stack).
(vii) Site name.
(viii) Physical address.
(ix) SCC.
(x) Pollutant code.
(xi) Ozone season emissions.
(xii) Area designation.
(2) In addition, the annual data must include the following minimum elements as applicable to the emissions estimation methodology.
(i) Fuel heat content (annual).
(ii) Fuel heat content (seasonal).
(iii) Source of fuel heat content data.
(iv) Activity throughput (annual).
(v) Activity throughput (seasonal).
(vi) Source of activity/throughput data.
(vii) Spring throughput (%).
(viii) Summer throughput (%).
(ix) Fall throughput (%).
(x) Work weekday emissions.
(xi) Emission factor.
(xii) Source of emission factor.
(xiii) Hour/day in operation.
(xiv) Operations Start time (hour).
(xv) Day/week in operation.
(xvi) Week/year in operation.
(3) The triennial and 2007 inventories must include the following data elements:
(i) The data required in paragraphs (c)(1) and (c)(2) of this section.
(ii) X coordinate (latitude).
(iii) Y coordinate (longitude).
(iv) Stack height.
(v) Stack diameter.
(vi) Exit gas temperature.
(vii) Exit gas velocity.
(viii) Exit gas flow rate.
(ix) SIC.
(x) Boiler/process throughput design capacity.
(xi) Maximum design rate.
(xii) Maximum capacity.
(xiii) Primary control efficiency.
(xiv) Secondary control efficiency.
(xv) Control device type.
(d) The data reported in paragraph (b) of this section for area sources must include the following minimum elements:
(1) For annual inventories it must include:
(i) Inventory year.
(ii) State FIPS code.
(iii) County FIPS code.
(iv) SCC.
(v) Emission factor.
(vi) Source of emission factor.
(vii) Activity/throughput level (annual).
(viii) Activity throughput level (seasonal).
(ix) Source of activity/throughput data.
(x) Spring throughput (%).
(xi) Summer throughput (%).
(xii) Fall throughput (%).
(xiii) Control efficiency (%).
(xiv) Pollutant code.
(xv) Ozone season emissions.
(xvi) Source of emissions data.
(xvii) Hour/day in operation.
(xviii) Day/week in operation.
(xix) Week/year in operations.
(2) The triennial and 2007 inventories must contain, at a minimum, all the data required in paragraph (d)(1) of this section.
(e) The data reported in paragraph (b) of this section for mobile sources must meet the following minimum criteria:
(1) For the annual, triennial, and 2007 inventory purposes, the following data must be reported:
(i) Inventory year.
(ii) State FIPS code.
(iii) County FIPS code.
(iv) SCC.
(v) Emission factor.
(vi) Source of emission factor.
(vii) Activity (this must be reported for both highway and nonroad activity. Submit nonroad activity in the form of hours of activity at standard load (either full load or average load) for each engine type, application, and horsepower range. Submit highway activity in the form of vehicle miles traveled (VMT) by vehicle class on each roadway type. Report both highway and nonroad activity for a typical ozone season weekday day, if the State uses EPA's default weekday/weekend activity ratio. If the State uses a different weekday/weekend activity ratio, submit separate activity level information for weekday days and weekend days).
(viii) Source of activity data.
(ix) Pollutant code.
(x) Summer work weekday emissions.
(xi) Ozone season emissions.
(xii) Source of emissions data.
(2) [Reserved]
(f)
(g)
(2) Triennial reports are to begin with data for emissions occurring in the year 2002.
(3) Year 2007 data are to be submitted for emissions occurring in the year 2007.
(4) States must submit data for a required year no later than 12 months after the end of the calendar year for which the data are collected.
(h)
(1) States are required to report emissions data in an electronic format to one of the locations listed in this paragraph (h). Several options are available for data reporting.
(2) An agency may choose to continue reporting to the EPA Aerometric Information Retrieval System (AIRS) system using the AIRS facility subsystem (AFS) format for point sources. (This option will continue for point sources for some period of time after AIRS is reengineered (before 2002), at which time this choice may be discontinued or modified.)
(3) An agency may convert its emissions data into the Emission Inventory Improvement Program/Electronic Data Interchange (EIIP/EDI) format. This file can then be made available to any requestor, either using E-mail, floppy disk, or value added network (VAN), or can be placed on a file transfer protocol (FTP) site.
(4) An agency may submit its emissions data in a proprietary format based on the EIIP data model.
(5) For options in paragraphs (h)(3) and (4) of this section, the terms submitting and reporting data are defined as either providing the data in the EIIP/EDI format or the EIIP based data model proprietary format to EPA, Office of Air Quality Planning and Standards, Emission Factors and Inventory Group, directly or notifying this group that the data are available in the specified format and at a specific electronic location (e.g., FTP site).
(6) For annual reporting (not for triennial reports), a State may have sources submit the data directly to EPA to the extent the sources are subject to a trading program that qualifies for approval under § 51.121(q) of this part, and the State has agreed to accept data in this format. The EPA will make both the raw data submitted in this format and summary data available to any State that chooses this option.
(i)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(i)
(ii)
(iii)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
(41)
(42)
(a) This section continues the classification system for episode plans. Each region is classified separately with respect to each of the following pollutants: Sulfur oxides, particulate matter, carbon monoxide, nitrogen dioxide, and ozone.
(b)
(1) Sulfur dioxide—100 μg/m
(2) Particulate matter—95 μg/m
(3) Carbon monoxide—55 mg/m
(4) Nitrogen dioxide—100 μg/m
(5) Ozone—195 μg/m
(c)
(d)
(1) Sulfur Dioxides—60-100 μg/m
(2) Particulate matter—60-95 μg/m
(e) In the absence of adequate monitoring data, appropriate models must be used to classify an area under paragraph (b) of this section, consistent with the requirements contained in § 51.112(a).
(f) Areas which do not meet the above criteria are classified Priority III.
Each plan for a Priority I region must include a contingency plan which must, as a mimimum, provide for taking action necessary to prevent ambient pollutant concentrations at any location in such region from reaching the following levels:
(a) Each contingency plan must—
(1) Specify two or more stages of episode criteria such as those set forth in appendix L to this part, or their equivalent;
(2) Provide for public announcement whenever any episode stage has been determined to exist; and
(3) Specify adequate emission control actions to be taken at each episode stage. (Examples of emission control actions are set forth in appendix L.)
(b) Each contingency plan for a Priority I region must provide for the following:
(1) Prompt acquisition of forecasts of atmospheric stagnation conditions and of updates of such forecasts as frequently as they are issued by the National Weather Service.
(2) Inspection of sources to ascertain compliance with applicable emission control action requirements.
(3) Communications procedures for transmitting status reports and orders as to emission control actions to be taken during an episode stage, including procedures for contact with public officials, major emission sources, public health, safety, and emergency agencies and news media.
(c) Each plan for a Priority IA and II region must include a contingency plan that meets, as a minimum, the requirements of paragraphs (b)(1) and (b)(2) of this section. Areas classified Priority III do not need to develop episode plans.
(d) Notwithstanding the requirements of paragraphs (b) and (c) of this section, the Administrator may, at his discretion—
(1) Exempt from the requirements of this section those portions of Priority I, IA, or II regions which have been designated as attainment or unclassifiable for national primary and secondary standards under section 107 of the Act; or
(2) Limit the requirements pertaining to emission control actions in Priority I regions to—
(i) Urbanized areas as identified in the most recent United States Census, and
(ii) Major emitting facilities, as defined by section 169(1) of the Act, outside the urbanized areas.
(a) States should periodically reevaluate priority classifications of all Regions or portion of Regions within their borders. The reevaluation must consider the three most recent years of air quality data. If the evaluation indicates a change to a higher priority classification, appropriate changes in the episode plan must be made as expeditiously as practicable.
(b) [Reserved]
(a) Each plan must set forth legally enforceable procedures that enable the State or local agency to determine whether the construction or modification of a facility, building, structure or installation, or combination of these will result in—
(1) A violation of applicable portions of the control strategy; or
(2) Interference with attainment or maintenance of a national standard in the State in which the proposed source (or modification) is located or in a neighboring State.
(b) Such procedures must include means by which the State or local agency responsible for final decisionmaking on an application for approval to construct or modify will prevent such construction or modification if—
(1) It will result in a violation of applicable portions of the control strategy; or
(2) It will interfere with the attainment or maintenance of a national standard.
(c) The procedures must provide for the submission, by the owner or operator of the building, facility, structure, or installation to be constructed or modified, of such information on—
(1) The nature and amounts of emissions to be emitted by it or emitted by associated mobile sources;
(2) The location, design, construction, and operation of such facility, building, structure, or installation as may be necessary to permit the State or local agency to make the determination referred to in paragraph (a) of this section.
(d) The procedures must provide that approval of any construction or modification must not affect the responsibility to the owner or operator to comply with applicable portions of the control strategy.
(e) The procedures must identify types and sizes of facilities, buildings, structures, or installations which will be subject to review under this section. The plan must discuss the basis for determining which facilities will be subject to review.
(f) The procedures must discuss the air quality data and the dispersion or other air quality modeling used to meet the requirements of this subpart.
(1) All applications of air quality modeling involved in this subpart shall be based on the applicable models, data bases, and other requirements specified in appendix W of this part (Guideline on Air Quality Models).
(2) Where an air quality model specified in appendix W of this part (Guideline on Air Quality Models) is inappropriate, the model may be modified or another model substituted. Such a modification or substitution of a model may be made on a case-by-case basis or, where appropriate, on a generic basis for a specific State program. Written approval of the Administrator must be obtained for any modification or substitution. In addition, use of a modified or substituted model must be subject to notice and opportunity for public comment under procedures set forth in § 51.102.
(a) The legally enforceable procedures in § 51.160 must also require the State or local agency to provide opportunity for public comment on information submitted by owners and operators. The public information must include the agency's analysis of the effect of construction or modification on ambient air quality, including the
(b) For purposes of paragraph (a) of this section, opportunity for public comment shall include, as a minimum—
(1) Availability for public inspection in at least one location in the area affected of the information submitted by the owner or operator and of the State or local agency's analysis of the effect on air quality;
(2) A 30-day period for submittal of public comment; and
(3) A notice by prominent advertisement in the area affected of the location of the source information and analysis specified in paragraph (b)(1) of this section.
(c) Where the 30-day comment period required in paragraph (b) of this section would conflict with existing requirements for acting on requests for permission to construct or modify, the State may submit for approval a comment period which is consistent with such existing requirements.
(d) A copy of the notice required by paragraph (b) of this section must also be sent to the Administrator through the appropriate Regional Office, and to all other State and local air pollution control agencies having jurisdiction in the region in which such new or modified installation will be located. The notice also must be sent to any other agency in the region having responsibility for implementing the procedures required under this subpart. For lead, a copy of the notice is required for all point sources. The definition of point for lead is given in § 51.100(k)(2).
Each plan must identify the State or local agency which will be responsible for meeting the requirements of this subpart in each area of the State. Where such responsibility rests with an agency other than an air pollution control agency, such agency will consult with the appropriate State or local air pollution control agency in carrying out the provisions of this subpart.
The plan must include the administrative procedures, which will be followed in making the determination specified in paragraph (a) of § 51.160.
Such procedures must provide that the degree of emission limitation required of any source for control of any air pollutant must not be affected by so much of any source's stack height that exceeds good engineering practice or by any other dispersion technique, except as provided in § 51.118(b). Such procedures must provide that before a State issues a permit to a source based on a good engineering practice stack height that exceeds the height allowed by § 51.100(ii) (1) or (2), the State must notify the public of the availability of the demonstration study and must provide opportunity for public hearing on it. This section does not require such procedures to restrict in any manner the actual stack height of any source.
(a) State Implementation Plan provisions satisfying sections 172(b)(6) and 173 of the Act shall meet the following conditions:
(1) All such plans shall use the specific definitions. Deviations from the following wording will be approved only if the State specifically demonstrates that the submitted definition is more stringent, or at least as stringent, in all respects as the corresponding definition below:
(i)
(ii)
(iii)
(iv)(A)
(
(
(B) A major stationary source that is major for volatile organic compounds shall be considered major for ozone
(C) The fugitive emissions of a stationary source shall not be included in determining for any of the purposes of this paragraph whether it is a major stationary source, unless the source belongs to one of the following categories of stationary sources:
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(v)(A)
(B) Any net emissions increase that is considered significant for volatile organic compounds shall be considered significant for ozone.
(C) A physical change or change in the method of operation shall not include:
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(vi)(A)
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(B) An increase or decrease in actual emissions is contemporaneous with the increase from the particular change only if it occurs before the date that the increase from the particular change occurs;
(C) An increase or decrease in actual emissions is creditable only if:
(
(
(D) An increase in actual emissions is creditable only to the extent that the new level of actual emissions exceeds the old level.
(E) A decrease in actual emissions is creditable only to the extent that:
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(F) An increase that results from a physical change at a source occurs
(vii)
(viii)
(ix)
(x)
(xi)
(A) The applicable standards set forth in 40 CFR part 60 or 61;
(B) Any applicable State Implementation Plan emissions limitation including those with a future compliance date; or
(C) The emissions rate specified as a federally enforceable permit condition, including those with a future compliance date.
(xii)(A)
(B) In general, actual emissions as of a particular date shall equal the average rate, in tons per year, at which the unit actually emitted the pollutant during a two-year period which precedes the particular date and which is representative of normal source operation. The reviewing authority shall allow the use of a different time period upon a determination that it is more representative of normal source operation. Actual emissions shall be calculated using the unit's actual operating hours, production rates, and types of materials processed, stored, or combusted during the selected time period.
(C) The reviewing authority may presume that the source-specific allowable emissions for the unit are equivalent to the actual emissions of the unit.
(D) For any emissions unit (other than an electric utility steam generating unit specified in paragraph (a)(1)(xii)(E) of this section) which has not begun normal operations on the particular date, actual emissions shall equal the potential to emit of the unit on that date.
(E) For an electric utility steam generating unit (other than a new unit or the replacement of an existing unit) actual emissions of the unit following the physical or operational change shall equal the representative actual annual emissions of the unit, provided the source owner or operator maintains and submits to the reviewing authority, on an annual basis for a period of 5 years from the date the unit resumes
(xiii)
(A) The most stringent emissions limitation which is contained in the implementation plan of any State for such class or category of stationary source, unless the owner or operator of the proposed stationary source demonstrates that such limitations are not achievable; or
(B) The most stringent emissions limitation which is achieved in practice by such class or category of stationary sources. This limitation, when applied to a modification, means the lowest achievable emissions rate for the new or modified emissions units within or stationary source. In no event shall the application of the term permit a proposed new or modified stationary source to emit any pollutant in excess of the amount allowable under an applicable new source standard of performance.
(xiv)
(xv)
(xvi)
(A) Begun, or caused to begin, a continuous program of actual on-site construction of the source, to be completed within a reasonable time; or
(B) Entered into binding agreements or contractual obligations, which cannot be canceled or modified without substantial loss to the owner or operator, to undertake a program of actual construction of the source to be completed within a reasonable time.
(xvii)
(xviii)
(xix)
(xx)
(xxi)
(A) Consider all relevant information, including but not limited to, historical operational data, the company's own representations, filings with the State or Federal regulatory authorities, and compliance plans under title IV of the Clean Air Act; and
(B) Exclude, in calculating any increase in emissions that results from the particular physical change or change in the method of operation at an electric utility steam generating unit, that portion of the unit's emissions following the change that could have been accommodated during the representative baseline period and is attributable to an increase in projected capacity utilization at the unit that is unrelated to the particular change, including any increased utilization due to the rate of electricity demand growth for the utility system as a whole.
(xxii)
(xxiii)
(xxiv)
(xxv)
(A) The installation of conventional or innovative pollution control technology, including but not limited to advanced flue gas desulfurization, sorbent injection for sulfur dioxide and nitrogen oxides controls and electrostatic precipitators;
(B) An activity or project to accommodate switching to a fuel which is less polluting than the fuel used prior to the activity or project, including, but not limited to natural gas or coal reburning, or the cofiring of natural gas and other fuels for the purpose of controlling emissions;
(C) A permanent clean coal technology demonstration project conducted under title II, sec. 101(d) of the Further Continuing Appropriations Act of 1985 (sec. 5903(d) of title 42 of the United States Code), or subsequent appropriations, up to a total amount of $2,500,000,000 for commercial demonstration of clean coal technology, or similar projects funded through appropriations for the Environmental Protection Agency; or
(D) A permanent clean coal technology demonstration project that constitutes a repowering project.
(2) Each plan shall adopt a preconstruction review program to satisfy the requirements of sections 172(b)(6) and 173 of the Act for any area designated nonattainment for any national ambient air quality standard under 40 CFR 81.300
(3)(i) Each plan shall provide that for sources and modifications subject to any preconstruction review program adopted pursuant to this subsection the baseline for determining credit for emissions reductions is the emissions limit under the applicable State Implementation Plan in effect at the time the application to construct is filed, except that the offset baseline shall be the actual emissions of the source from which offset credit is obtained where;
(A) The demonstration of reasonable further progress and attainment of ambient air quality standards is based upon the actual emissions of sources located within a designated nonattainment area for which the pre-con-struction review program was adopted; or
(B) The applicable State Implementation Plan does not contain an emissions limitation for that source or source category.
(ii) The plan shall further provide that:
(A) Where the emissions limit under the applicable State Implementation Plan allows greater emissions than the potential to emit of the source, emissions offset credit will be allowed only for control below this potential;
(B) For an existing fuel combustion source, credit shall be based on the allowable emissions under the applicable State Implementation Plan for the type of fuel being burned at the time the application to construct is filed. If the existing source commits to switch to a cleaner fuel at some future date, emissions offset credit based on the allowable (or actual) emissions for the fuels involved is not acceptable, unless the permit is conditioned to require the use of a specified alternative control measure which would achieve the same degree of emissions reduction should the source switch back to a dirtier fuel at some later date. The reviewing authority should ensure that adequate long-term supplies of the new fuel are available before granting emissions offset credit for fuel switches,
(C)(
(
(D) No emissions credit may be allowed for replacing one hydrocarbon compound with another of lesser reactivity, except for those compounds listed in Table 1 of EPA's “Recommended Policy on Control of Volatile Organic Compounds” (42 FR 35314, July 8, 1977; (This document is also available from Mr. Ted Creekmore, Office of Air Quality Planning and Standards, (MD-15) Research Triangle Park, NC 27711.))
(E) All emission reductions claimed as offset credit shall be federally enforceable;
(F) Procedures relating to the permissible location of offsetting emissions shall be followed which are at least as stringent as those set out in 40 CFR part 51 appendix S section IV.D.
(G) Credit for an emissions reduction can be claimed to the extent that the reviewing authority has not relied on it in issuing any permit under regulations approved pursuant to 40 CFR part 51 subpart I or the State has not relied on it in demonstration attainment or reasonable further progress.
(4) Each plan may provide that the provisions of this paragraph do not apply to a source or modification that would be a major stationary source or major modification only if fugitive emission to the extent quantifiable are considered in calculating the potential to emit of the stationary source or modification and the source does not belong to any of the following categories:
(i) Coal cleaning plants (with thermal dryers);
(ii) Kraft pulp mills;
(iii) Portland cement plants;
(iv) Primary zinc smelters;
(v) Iron and steel mills;
(vi) Primary aluminum ore reduction plants;
(vii) Primary copper smelters;
(viii) Municipal incinerators capable of charging more than 250 tons of refuse per day;
(ix) Hydrofluoric, sulfuric, or citric acid plants;
(x) Petroleum refineries;
(xi) Lime plants;
(xii) Phosphate rock processing plants;
(xiii) Coke oven batteries;
(xiv) Sulfur recovery plants;
(xv) Carbon black plants (furnace process);
(xvi) Primary lead smelters;
(xvii) Fuel conversion plants;
(xviii) Sintering plants;
(xix) Secondary metal production plants;
(xx) Chemical process plants;
(xxi) Fossil-fuel boilers (or combination thereof) totaling more than 250 million British thermal units per hour heat input;
(xxii) Petroleum storage and transfer units with a total storage capacity exceeding 300,000 barrels;
(xxiii) Taconite ore processing plants;
(xxiv) Glass fiber processing plants;
(xxv) Charcoal production plants;
(xxvi) Fossil fuel-fired steam electric plants of more than 250 million British thermal units per hour heat input;
(xxvii) Any other stationary source category which, as of August 7, 1980, is being regulated under section 111 or 112 of the Act.
(5) Each plan shall include enforceable procedures to provide that:
(i) Approval to construct shall not relieve any owner or operator of the responsibility to comply fully with applicable provision of the plan and any other requirements under local, State or Federal law.
(ii) At such time that a particular source or modification becomes a major stationary source or major modification solely by virtue of a relaxation in any enforcement limitation which was established after August 7, 1980, on the capacity of the source or modification otherwise to emit a pollutant, such as a restriction on hours of operation, then the requirements of regulations approved pursuant to this section shall apply to the source or modification as though construction had not yet commenced on the source or modification;
(b)(1) Each plan shall include a preconstruction review permit program or its equivalent to satisfy the requirements of section 110(a)(2)(D)(i) of the Act for any new major stationary source or major modification as defined in paragraphs (a)(1) (iv) and (v) of this section. Such a program shall apply to any such source or modification that would locate in any area designated as attainment or unclassifiable for any national ambient air quality standard pursuant to section 107 of the Act, when it would cause or contribute to a violation of any national ambient air quality standard.
(2) A major source or major modification will be considered to cause or contribute to a violation of a national ambient air quality standard when such source or modification would, at a minimum, exceed the following significance levels at any locality that does not or would not meet the applicable national standard:
(3) Such a program may include a provision which allows a proposed major source or major modification subject to paragraph (b) of this section to reduce the impact of its emissions upon air quality by obtaining sufficient emission reductions to, at a minimum, compensate for its adverse ambient impact where the major source or major modification would otherwise cause or contribute to a violation of any national ambient air quality standard. The plan shall require that, in the absence of such emission reductions, the State or local agency shall deny the proposed construction.
(4) The requirements of paragraph (b) of this section shall not apply to a major stationary source or major modification with respect to a particular pollutant if the owner or operator demonstrates that, as to that pollutant, the source or modification is located in an area designated as nonattainment pursuant to section 107 of the Act.
(a)(1)
(2)
(3)
(4)
(5)
(6)
(ii) Any revision to an implementation plan that would amend the provisions for the prevention of significant air quality deterioration in the plan shall specify when and as to what
(iii) Any revision to an implementation plan that an amendment to this section required shall take effect no later than the date of its approval and may operate prospectively.
(b)
(1)(i)
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(ii) A major source that is major for volatile organic compounds shall be considered major for ozone.
(iii) The fugitive emissions of a stationary source shall not be included in determining for any of the purposes of this section whether it is a major stationary source, unless the source belongs to one of the following categories of stationary sources:
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(2)(i)
(ii) Any net emissions increase that is significant for volatile organic compounds shall be considered significant for ozone.
(iii) A physical change or change in the method of operation shall not include:
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(3)(i)
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(ii) An increase or decrease in actual emissions is contemporaneous with the increase from the particular change only if it occurs within a reasonable
(iii) An increase or decrease in actual emissions is creditable only if the reviewing authority has not relied on it in issuing a permit for the source under regulations approved pursuant to this section, which permit is in effect when the increase in actual emissions from the particular change occurs.
(iv) An increase or decrease in actual emissions of sulfur dioxide, particulate matter, or nitrogen oxides, which occurs before the applicable minor source baseline date is creditable only if it is required to be considered in calculating the amount of maximum allowable increases remaining available. With respect to particulate matter, only PM-10 emissions can be used to evaluate the net emissions increase for PM-10.
(v) An increase in actual emissions is creditable only to the extent that the new level of actual emissions exceeds the old level.
(vi) A decrease in actual emissions is creditable only to the extent that:
(
(
(
(vii) An increase that results from a physical change at a source occurs when the emissions unit on which construction occurred becomes operational and begins to emit a particular pollutant. Any replacement unit that requires shakedown becomes operational only after a reasonable shakedown period, not to exceed 180 days.
(4)
(5)
(6)
(7)
(8)
(9)
(i) Begun, or caused to begin, a continuous program of actual on-site construction of the source, to be completed within a reasonable time; or
(ii) Entered into binding agreements or contractual obligations, which cannot be cancelled or modified without substantial loss to the owner or operator, to undertake a program of actual construction of the source to be completed within a reasonable time.
(10)
(11)
(12)
(13)(i)
(
(
(ii) The following will not be included in the baseline concentration and will affect the applicable maximum allowable increase(s):
(
(
(14)(i)
(
(
(ii)
(
(
(iii) The baseline date is established for each pollutant for which increments or other equivalent measures have been established if:
(
(
(iv) Any minor source baseline date established originally for the TSP increments shall remain in effect and shall apply for purposes of determining the amount of available PM-10 increments, except that the reviewing authority may rescind any such minor source baseline date where it can be shown, to the satisfaction of the reviewing authority, that the emissions increase from the major stationary source, or the net emissions increase from the major modification, responsible for triggering that date did not result in a significant amount of PM-10 emissions.
(15)(i)
(ii) Area redesignations under section 107(d)(1) (D) or (E) of the Act cannot intersect or be smaller than the area of impact of any major stationary source or major modification which:
(
(
(iii) Any baseline area established originally for the TSP increments shall remain in effect and shall apply for purposes of determining the amount of available PM-10 increments, except that such baseline area shall not remain in effect if the permit authority rescinds the corresponding minor source baseline date in accordance with paragraph (b)(14)(iv) of this section.
(16)
(i) The applicable standards as set forth in 40 CFR parts 60 and 61;
(ii) The applicable State Implementation Plan emissions limitation, including those with a future compliance date; or
(iii) The emissions rate specified as a federally enforceable permit condition.
(17)
(18)
(19)
(20)
(21)(i)
(ii) In general, actual emissions as of a particular date shall equal the average rate, in tons per year, at which the unit actually emitted the pollutant during a two-year period which precedes the particular date and which is representative of normal source operation. The reviewing authority may allow the use of a different time period upon a determination that it is more representative of normal source operation. Actual emissions shall be calculated using the unit's actual operating hours, production rates, and types of materials processed, stored, or combusted during the selected time period.
(iii) The reviewing authority may presume that source-specific allowable emissions for the unit are equivalent to the actual emissions of the unit.
(iv) For any emissions unit (other than an electric utility steam generating unit specified in paragraph (b)(21)(v) of this section) which has not begun normal operations on the particular date, actual emissions shall equal the potential to emit of the unit on that date.
(v) For an electric utility steam generating unit (other than a new unit or the replacement of an existing unit) actual emissions of the unit following the physical or operational change shall equal the representative actual annual emissions of the unit following the physical or operational change, provided the source owner or operator maintains and submits to the reviewing authority, on an annual basis for a period of 5 years from the date the unit resumes regular operation, information demonstrating that the physical or operational change did not result in an emissions increase. A longer period, not to exceed 10 years, may be required by the reviewing authority if it determines such a period to be more representative of normal source post-change operations.
(22)
(23)(i)
(ii)
(iii) Notwithstanding paragraph (b)(23)(i) of this section,
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
(i) The installation of conventional or innovative pollution control technology, including but not limited to advanced flue gas desulfurization, sorbent injection for sulfur dioxide and nitrogen oxides controls and electrostatic precipitators;
(ii) An activity or project to accommodate switching to a fuel which is less polluting than the fuel used prior to the activity or project, including but not limited to natural gas or coal re-burning, or the co-firing of natural gas and other fuels for the purpose of controlling emissions;
(iii) A permanent clean coal technology demonstration project conducted under title II, section 101(d) of the Further Continuing Appropriations Act of 1985 (section 5903(d) of title 42 of the United States Code), or subsequent appropriations, up to a total amount of $2,500,000,000 for commercial demonstration of clean coal technology, or similar projects funded through appropriations for the Environmental Protection Agency, or
(iv) A permanent clean coal technology demonstration project that constitutes a repowering project.
(32)
(i) Consider all relevant information, including but not limited to, historical operational data, the company's own representations, filings with the State or Federal regulatory authorities, and compliance plans under title IV of the Clean Air Act; and
(ii) Exclude, in calculating any increase in emissions that results from the particular physical change or change in the method of operation at an electric utility steam generating
(33)
(34)
(35)
(36)(i)
(ii) Repowering shall also include any oil and/or gas-fired unit which has been awarded clean coal technology demonstration funding as of January 1, 1991, by the Department of Energy.
(iii) The reviewing authority shall give expedited consideration to permit applications for any source that satisfies the requirements of this subsection and is granted an extension under section 409 of the Clean Air Act.
(37)
(i) Has not been in operation for the two-year period prior to the enactment of the Clean Air Act Amendments of 1990, and the emissions from such unit continue to be carried in the permitting authority's emissions inventory at the time of enactment;
(ii) Was equipped prior to shutdown with a continuous system of emissions control that achieves a removal efficiency for sulfur dioxide of no less than 85 percent and a removal efficiency for particulates of no less than 98 percent;
(iii) Is equipped with low-NO
(iv) Is otherwise in compliance with the requirements of the Clean Air Act.
(c)
(d)
(1) The concentration permitted under the national secondary ambient air quality standard, or
(2) The concentration permitted under the national primary ambient air quality standard, whichever concentration is lowest for the pollutant for a period of exposure.
(e)
(1) All of the following areas which were in existence on August 7, 1977, shall be Class I areas and may not be redesignated:
(i) International parks,
(ii) National wilderness areas which exceed 5,000 acres in size,
(iii) National memorial parks which exceed 5,000 acres in size, and
(iv) National parks which exceed 6,000 acres in size.
(2) Areas which were redesignated as Class I under regulations promulgated before August 7, 1977, shall remain Class I, but may be redesignated as provided in this section.
(3) Any other area, unless otherwise specified in the legislation creating such an area, is initially designated Class II, but may be redesignated as provided in this section.
(4) The following areas may be redesignated only as Class I or II:
(i) An area which as of August 7, 1977, exceeded 10,000 acres in size and was a national monument, a national primitive area, a national preserve, a national recreational area, a national wild and scenic river, a national wildlife refuge, a national lakeshore or seashore; and
(ii) A national park or national wilderness area established after August 7, 1977, which exceeds 10,000 acres in size.
(f)
(i) Concentrations attributable to the increase in emissions from stationary sources which have converted from the use of petroleum products, natural gas, or both by reason of an order in effect under section 2 (a) and (b) of the Energy Supply and Environmental Coordination Act of 1974 (or any superseding legislation) over the emissions from such sources before the effective date of such an order;
(ii) Concentrations attributable to the increase in emissions from sources which have converted from using natural gas by reason of natural gas curtailment plan in effect pursuant to the Federal Power Act over the emissions from such sources before the effective date of such plan;
(iii) Concentrations of particulate matter attributable to the increase in emissions from construction or other temporary emission-related activities of new or modified sources;
(iv) The increase in concentrations attributable to new sources outside the United States over the concentrations
(v) Concentrations attributable to the temporary increase in emissions of sulfur dioxide, particulate matter, or nitrogen oxides from stationary sources which are affected by plan revisions approved by the Administrator as meeting the criteria specified in paragraph (f)(4) of this section.
(2) If the plan provides that the concentrations to which paragraph (f)(1) (i) or (ii) of this section, refers shall be excluded, it shall also provide that no exclusion of such concentrations shall apply more than five years after the effective date of the order to which paragraph (f)(1)(i) of this section, refers or the plan to which paragraph (f)(1)(ii) of this section, refers, whichever is applicable. If both such order and plan are applicable, no such exclusion shall apply more than five years after the later of such effective dates.
(3) [Reserved]
(4) For purposes of excluding concentrations pursuant to paragraph (f)(1)(v) of this section, the Administrator may approve a plan revision that:
(i) Specifies the time over which the temporary emissions increase of sulfur dioxide, particulate matter, or nitrogen oxides would occur. Such time is not to exceed 2 years in duration unless a longer time is approved by the Administrator.
(ii) Specifies that the time period for excluding certain contributions in accordance with paragraph (f)(4)(i) of this section, is not renewable;
(iii) Allows no emissions increase from a stationary source which would:
(
(
(iv) Requires limitations to be in effect the end of the time period specified in accordance with paragraph (f)(4)(i) of this section, which would ensure that the emissions levels from stationary sources affected by the plan revision would not exceed those levels occurring from such sources before the plan revision was approved.
(g)
(2) The plan may provide that the State may submit to the Administrator a proposal to redesignate areas of the State Class I or Class II:
(i) At least one public hearing has been held in accordance with procedures established in § 51.102.
(ii) Other States, Indian Governing Bodies, and Federal Land Managers whose lands may be affected by the proposed redesignation were notified at least 30 days prior to the public hearing;
(iii) A discussion of the reasons for the proposed redesignation, including a satisfactory description and analysis of the health, environmental, economic, social, and energy effects of the proposed redesignation, was prepared and made available for public inspection at least 30 days prior to the hearing and the notice announcing the hearing contained appropriate notification of the availability of such discussion;
(iv) Prior to the issuance of notice respecting the redesignation of an area that includes any Federal lands, the State has provided written notice to the appropriate Federal Land Manager and afforded adequate opportunity (not in excess of 60 days) to confer with the State respecting the redesignation and to submit written comments and recommendations. In redesignating any area with respect to which any Federal Land Manager had submitted written comments and recommendations, the State shall have published a list of any inconsistency between such redesignation and such comments and recommendations (together with the reasons for making such redesignation
(v) The State has proposed the redesignation after consultation with the elected leadership of local and other substate general purpose governments in the area covered by the proposed redesignation.
(3) The plan may provide that any area other than an area to which paragraph (e) of this section refers may be redesignated as Class III if—
(i) The redesignation would meet the requirements of provisions established in accordance with paragraph (g)(2) of this section;
(ii) The redesignation, except any established by an Indian Governing Body, has been specifically approved by the Governor of the State, after consultation with the appropriate committees of the legislature, if it is in session, or with the leadership of the legislature, if it is not in session (unless State law provides that such redesignation must be specifically approved by State legislation) and if general purpose units of local government representing a majority of the residents of the area to be redesignated enact legislation (including resolutions where appropriate) concurring in the redesignation;
(iii) The redesignation would not cause, or contribute to, a concentration of any air pollutant which would exceed any maximum allowable increase permitted under the classification of any other area or any national ambient air quality standard; and
(iv) Any permit application for any major stationary source or major modification subject to provisions established in accordance with paragraph (l) of this section which could receive a permit only if the area in question were redesignated as Class III, and any material submitted as part of that application, were available, insofar as was practicable, for public inspection prior to any public hearing on redesignation of any area as Class III.
(4) The plan shall provide that lands within the exterior boundaries of Indian Reservations may be redesignated only by the appropriate Indian Governing Body. The appropriate Indian Governing Body may submit to the Administrator a proposal to redesignate areas Class I, Class II, or Class III:
(i) The Indian Governing Body has followed procedures equivalent to those required of a State under paragraphs (g) (2), (3)(iii), and (3)(iv) of this section; and
(ii) Such redesignation is proposed after consultation with the State(s) in which the Indian Reservation is located and which border the Indian Reservation.
(5) The Administrator shall disapprove, within 90 days of submission, a proposed redesignation of any area only if he finds, after notice and opportunity for public hearing, that such redesignation does not meet the procedural requirements of this section or is inconsistent with paragraph (e) of this section. If any such disapproval occurs, the classification of the area shall be that which was in effect prior to the redesignation which was disapproved.
(6) If the Administrator disapproves any proposed area designation, the State or Indian Governing Body, as appropriate, may resubmit the proposal after correcting the deficiencies noted by the Administrator.
(h)
(1) So much of a stack height, not in existence before December 31, 1970, as exceeds good engineering practice, or
(2) Any other dispersion technique not implemented before then.
(i)
(1) The plan shall provide that no major stationary source or major modification shall begin actual construction unless, as a minumum, requirements equivalent to those contained in paragraphs (j) through (r) of this section have been met.
(2) The plan shall provide that the requirements equivalent to those contained in paragraphs (j) through (r) of this section shall apply to any major stationary source and any major modification with respect to each pollutant subject to regulation under the Act
(3) The plan shall provide that requirements equivalent to those contained in paragraphs (j) through (r) of this section apply only to any major stationary source or major modification that would be constructed in an area which is designated as attainment or unclassifiable under section 107(a)(1) (D) or (E) of the Act; and
(4) The plan may provide that requirements equivalent to those contained in paragraphs (j) through (r) of this section do not apply to a particular major stationary source or major modification if:
(i) The major stationary source would be a nonprofit health or nonprofit educational institution or a major modification that would occur at such an institution; or
(ii) The source or modification would be a major stationary source or major modification only if fugitive emissions, to the extent quantifiable, are considered in calculating the potential to emit of the stationary source or modification and such source does not belong to any following categories:
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(iii) The source or modification is a portable stationary source which has previously received a permit under requirements equivalent to those contained in paragraphs (j) through (r) of this section, if:
(
(
(
(
(5) The plan may provide that requirements equivalent to those contained in paragraphs (j) through (r) of this section do not apply to a major stationary source or major modification with respect to a particular pollutant if the owner or operator demonstrates that, as to that pollutant, the source or modification is located in an area designated as nonattainment under section 107 of the Act.
(6) The plan may provide that requirements equivalent to those contained in paragraphs (k), (m), and (o) of this section do not apply to a proposed major stationary source or major modification with respect to a particular pollutant, if the allowable
(7) The plan may provide that requirements equivalent to those contained in paragraphs (k), (m), and (o) of this section as they relate to any maximum allowable increase for a Class II area do not apply to a modification of a major stationary source that was in existence on March 1, 1978, if the net increase in allowable emissions of each pollutant subject to regulation under the Act from the modification after the application of best available control technology would be less than 50 tons per year.
(8) The plan may provide that the reviewing authority may exempt a proposed major stationary source or major modification from the requirements of paragraph (m) of this section, with respect to monitoring for a particular pollutant, if:
(i) The emissions increase of the pollutant from a new stationary source or the net emissions increase of the pollutant from a modification would cause, in any area, air quality impacts less than the following amounts:
(
(
(c) Particulate matter—10 μg/m
(
(
(
(
(
(
(
(
(
(
(ii) The concentrations of the pollutant in the area that the source or modification would affect are less than the concentrations listed in (i)(8)(i) of this section; or
(iii) The pollutants is not listed in paragraph (i)(8)(i) of this section.
(9) If EPA approves a plan revision under 40 CFR 51.166 as in effect before August 7, 1980, any subsequent revision which meets the requirements of this section may contain transition provisions which parallel the transition provisions of 40 CFR 52.21(i)(9), (i)(10) and (m)(1)(v) as in effect on that date, which provisions relate to requirements for best available control technology and air quality analyses. Any such subsequent revision may not contain any transition provision which in the context of the revision would operate any less stringently than would its counterpart in 40 CFR 52.21.
(10) If EPA approves a plan revision under § 51.166 as in effect [before July 31, 1987], any subsequent revision which meets the requirements of this section may contain transition provisions which parallel the transition provisions of § 52.21 (i)(11), and (m)(1) (vii) and (viii) of this chapter as in effect on that date, these provisions being related to monitoring requirements for particulate matter. Any such subsequent revision may not contain any transition provision which in the context of the revision would operate any less stringently than would its counterpart in § 52.21 of this chapter.
(11) The plan may provide that the permitting requirements equivalent to those contained in paragraph (k)(2) of this section do not apply to a stationary source or modification with respect to any maximum allowable increase for nitrogen oxides if the owner or operator of the source or modification submitted an application for a permit under the applicable permit program approved or promulgated under the Act before the provisions embodying the maximum allowable increase took effect as part of the plan and the
(12) The plan may provide that the permitting requirements equivalent to those contained in paragraph (k)(2) of this section shall not apply to a stationary source or modification with respect to any maximum allowable increase for PM-10 if (i) the owner or operator of the source or modification submitted an application for a permit under the applicable permit program approved under the Act before the provisions embodying the maximum allowable increases for PM-10 took effect as part of the plan, and (ii) the permitting authority subsequently determined that the application as submitted before that date was complete. Instead, the applicable requirements equivalent to paragraph (k)(2) shall apply with respect to the maximum allowable increases for TSP as in effect on the date the application was submitted.
(j)
(1) A major stationary source or major modification shall meet each applicable emissions limitation under the State Implementation Plan and each applicable emission standards and standard of performance under 40 CFR parts 60 and 61.
(2) A new major stationary source shall apply best available control technology for each pollutant subject to regulation under the Act that it would have the potential to emit in significant amounts.
(3) A major modification shall apply best available control technology for each pollutant subject to regulation under the Act for which it would be a significant net emissions increase at the source. This requirement applies to each proposed emissions unit at which a net emissions increase in the pollutant would occur as a result of a physical change or change in the method of operation in the unit.
(4) For phased construction projects, the determination of best available control technology shall be reviewed and modified as appropriate at the least reasonable time which occurs no later than 18 months prior to commencement of construction of each independent phase of the project. At such time, the owner or operator of the applicable stationary source may be required to demonstrate the adequacy of any previous determination of best available control technology for the source.
(k)
(1) Any national ambient air quality standard in any air quality control region; or
(2) Any applicable maximum allowable increase over the baseline concentration in any area.
(l)
(1) All applications of air quality modeling involved in this subpart shall be based on the applicable models, data bases, and other requirements specified in appendix W of this part (Guideline on Air Quality Models).
(2) Where an air quality model specified in appendix W of this part (Guideline on Air Quality Models) is inappropriate, the model may be modified or another model substituted. Such a modification or substitution of a model may be made on a case-by-case basis or, where appropriate, on a generic basis for a specific State program. Written approval of the Administrator must be obtained for any modification or substitution. In addition, use of a modified or substituted model must be subject to notice and opportunity for public comment under procedures set forth in § 51.102.
(m)
(
(
(ii) The plan shall provide that, with respect to any such pollutant for which no National Ambient Air Quality Standard exists, the analysis shall contain such air quality monitoring data as the reviewing authority determines is necessary to assess ambient air quality for that pollutant in any area that the emissions of that pollutant would affect.
(iii) The plan shall provide that with respect to any such pollutant (other than nonmethane hydrocarbons) for which such a standard does exist, the analysis shall contain continuous air quality monitoring data gathered for purposes of determining whether emissions of that pollutant would cause or contribute to a violation of the standard or any maxiumum allowable increase.
(iv) The plan shall provide that, in general, the continuous air monitoring data that is required shall have been gathered over a period of one year and shall represent the year preceding receipt of the application, except that, if the reviewing authority determines that a complete and adequate analysis can be accomplished with monitoring data gathered over a period shorter than one year (but not to be less than four months), the data that is required shall have been gathered over at least that shorter period.
(v) The plan may provide that the owner or operator of a proposed major stationary source or major modification of volatile organic compounds who satisfies all conditions of 40 CFR part 51 appendix S, section IV may provide postapproval monitoring data for ozone in lieu of providing preconstruction data as required under paragraph (m)(1) of this section.
(2)
(3)
(n)
(2) The plan may provide that such information shall include:
(i) A description of the nature, location, design capacity, and typical operating schedule of the source or modification, including specifications and drawings showing its design and plant layout;
(ii) A detailed schedule for construction of the source or modification;
(iii) A detailed description as to what system of continuous emission reduction is planned by the source or modification, emission estimates, and any other information as necessary to determine that best available control technology as applicable would be applied;
(3) The plan shall provide that upon request of the State, the owner or operator shall also provide information on:
(i) The air quality impact of the source or modification, including meteorological and topographical data necessary to estimate such impact; and
(ii) The air quality impacts and the nature and extent of any or all general commercial, residential, industrial, and other growth which has occurred since August 7, 1977, in the area the source or modification would affect.
(o)
(1) The owner or operator shall provide an analysis of the impairment to visibility, soils, and vegetation that would occur as a result of the source or modification and general commercial,
(2) The owner or operator shall provide an analysis of the air quality impact projected for the area as a result of general commercial, residential, industrial, and other growth associated with the source or modification.
(p)
(2)
(3)
(4)
(5)
(i) The owner or operator of a proposed source or modification which cannot be approved under procedures developed pursuant to paragraph (q)(4) of this section may demonstrate to the Governor that the source or modification cannot be constructed by reason of any maximum allowable increase for sulfur dioxide for periods of twenty-four hours or less applicable to any Class I area and, in the case of Federal mandatory Class I areas, that a variance under this clause would not adversely affect the air quality related values of the area (including visibility);
(ii) The Governor, after consideration of the Federal Land Manager's recommendation (if any) and subject to
(iii) If such variance is granted, the reviewing authority may issue a permit to such source or modification in accordance with provisions developed pursuant to paragraph (q)(7) of this section:
(6)
(i) The recommendations of the Governor and the Federal Land Manager shall be transferred to the President in any case where the Governor recommends a variance in which the Federal Land Manager does not concur;
(ii) The President may approve the Governor's recommendation if he finds that such variance is in the national interest; and
(iii) If such a variance is approved, the reviewing authority may issue a permit in accordance with provisions developed pursuant to the requirements of paragraph (q)(7) of this section:
(7)
(q)
(1) The reviewing authority shall notify all applicants within a specified time period as to the completeness of the application or any deficiency in the application or information submitted. In the event of such a deficiency, the date of receipt of the application shall be the date on which the reviewing authority received all required information.
(2) Within one year after receipt of a complete application, the reviewing authority shall:
(i) Make a preliminary determination whether construction should be approved, approved with conditions, or disapproved.
(ii) Make available in at least one location in each region in which the proposed source would be constructed a copy of all materials the applicant submitted, a copy of the preliminary determination, and a copy or summary of other materials, if any, considered in making the preliminary determination.
(iii) Notify the public, by advertisement in a newspaper of general circulation in each region in which the proposed source would be constructed, of the application, the preliminary determination, the degree of increment consumption that is expected from the source or modification, and of the opportunity for comment at a public hearing as well as written public comment.
(iv) Send a copy of the notice of public comment to the applicant, the Administrator and to officials and agencies having cognizance over the location where the proposed construction would occur as follows: Any other State or local air pollution control agencies, the chief executives of the city and county where the source would be located; any comprehensive regional land use planning agency, and any State, Federal Land Manager, or
(v) Provide opportunity for a public hearing for interested persons to appear and submit written or oral comments on the air quality impact of the source, alternatives to it, the control technology required, and other appropriate considerations.
(vi) Consider all written comments submitted within a time specified in the notice of public comment and all comments received at any public hearing(s) in making a final decision on the approvability of the application. The reviewing authority shall make all comments available for public inspection in the same locations where the reviewing authority made available preconstruction information relating to the proposed source or modification.
(vii) Make a final determination whether construction should be approved, approved with conditions, or disapproved.
(viii) Notify the applicant in writing of the final determination and make such notification available for public inspection at the same location where the reviewing authority made available preconstruction information and public comments relating to the source.
(r)
(2) The plan shall provide that at such time that a particular source or modification becomes a major stationary source or major modification solely by virtue of a relaxation in any enforceable limitation which was established after August 7, 1980, on the capacity of the source or modification otherwise to emit a pollutant, such as a restriction on hours of operation, then the requirements of paragraphs (j) through (s) of this section shall apply to the source or modification as though construction had not yet commenced on the source or modification.
(s)
(2) The plan may provide that the reviewing authority may, with the consent of the Governor(s) of other affected State(s), determine that the source or modification may employ a system of innovative control technology, if:
(i) The proposed control system would not cause or contribute to an unreasonable risk to public health, welfare, or safety in its operation or function;
(ii) The owner or operator agrees to achieve a level of continuous emissions reduction equivalent to that which would have been required under paragraph (j)(2) of this section, by a date specified by the reviewing authority. Such date shall not be later than 4 years from the time of startup or 7 years from permit issuance;
(iii) The source or modification would meet the requirements equivalent to those in paragraphs (j) and (k) of this section, based on the emissions rate that the stationary source employing the system of innovative control technology would be required to meet on the date specified by the reviewing authority;
(iv) The source or modification would not before the date specified by the reviewing authority:
(
(
(v) All other applicable requirements including those for public participation have been met.
(vi) The provisions of paragraph (p) of this section (relating to Class I areas) have been satisfied with respect to all periods during the life of the source or modification.
(3) The plan shall provide that the reviewing authority shall withdraw any approval to employ a system of innovative control technology made under this section, if:
(i) The proposed system fails by the specified date to achieve the required continuous emissions reduction rate; or
(ii) The proposed system fails before the specified date so as to contribute to an unreasonable risk to public health, welfare, or safety; or
(iii) The reviewing authority decides at any time that the proposed system is unlikely to achieve the required level of control or to protect the public health, welfare, or safety.
(4) The plan may provide that if a source or modification fails to meet the required level of continuous emissions reduction within the specified time period, or if the approval is withdrawn in accordance with paragraph (s)(3) of this section, the reviewing authority may allow the source or modification up to an additional 3 years to meet the requirement for the application of best available control technology through use of a demonstrated system of control.
For
Secs. 110, 301(a), 313, 319, Clean Air Act (42 U.S.C. 7410, 7601(a), 7613, 7619).
The requirements for monitoring ambient air quality for purposes of the plan are located in subpart C of part 58 of this chapter.
Each plan must provide for monitoring the status of compliance with any rules and regulations that set forth any portion of the control strategy. Specifically, the plan must meet the requirements of this subpart.
The plan must provide for legally enforceable procedures for requiring owners or operators of stationary sources to maintain records of and periodically report to the State—
(a) Information on the nature and amount of emissions from the stationary sources; and
(b) Other information as may be necessary to enable the State to determine whether the sources are in compliance with applicable portions of the control strategy.
The plan must provide for—
(a) Periodic testing and inspection of stationary sources; and
(b) Establishment of a system for detecting violations of any rules and regulations through the enforcement of appropriate visible emission limitations and for investigating complaints.
(c) Enforceable test methods for each emission limit specified in the plan. For the purpose of submitting compliance certifications or establishing whether or not a person has violated or is in violation of any standard in this part, the plan must not preclude the use, including the exclusive use, of any credible evidence or information, relevant to whether a source would have been in compliance with applicable requirements if the appropriate performance or compliance test or procedure had been performed. As an enforceable method, States may use:
(1) Any of the appropriate methods in appendix M to this part, Recommended Test Methods for State Implementation Plans; or
(2) An alternative method following review and approval of that method by the Administrator; or
(3) Any appropriate method in appendix A to 40 CFR part 60.
(a) The plan must contain procedures for obtaining and maintaining data on actual emissions reductions achieved as a result of implementing transportation control measures.
(b) In the case of measures based on traffic flow changes or reductions in vehicle use, the data must include observed changes in vehicle miles traveled and average speeds.
(c) The data must be maintained in such a way as to facilitate comparison of the planned and actual efficacy of the transportation control measures.
(a) The plan must contain legally enforceable procedures to—
(1) Require stationary sources subject to emission standards as part of an applicable plan to install, calibrate, maintain, and operate equipment for continuously monitoring and recording emissions; and
(2) Provide other information as specified in appendix P of this part.
(b) The procedures must—
(1) Identify the types of sources, by source category and capacity, that must install the equipment; and
(2) Identify for each source category the pollutants which must be monitored.
(c) The procedures must, as a minimum, require the types of sources set forth in appendix P of this part to meet the applicable requirements set forth therein.
(d)(1) The procedures must contain provisions that require the owner or operator of each source subject to continuous emission monitoring and recording requirements to maintain a file of all pertinent information for at least two years following the date of collection of that information.
(2) The information must include emission measurements, continuous monitoring system performance testing measurements, performance evaluations, calibration checks, and adjustments and maintenance performed on such monitoring systems and other reports and records required by appendix P of this part.
(e) The procedures must require the source owner or operator to submit information relating to emissions and operation of the emission monitors to the State to the extent described in appendix P at least as frequently as described therein.
(f)(1) The procedures must provide that sources subject to the requirements of paragraph (c) of this section must have installed all necessary equipment and shall have begun monitoring and recording within 18 months after either—
(i) The approval of a State plan requiring monitoring for that source; or
(ii) Promulgation by the Agency of monitoring requirements for that source.
(2) The State may grant reasonable extensions of this period to sources that—
(i) Have made good faith efforts to purchases, install, and begin the monitoring and recording of emission data; and
(ii) Have been unable to complete the installation within the period.
Each plan must show that the State has legal authority to carry out the plan, including authority to:
(a) Adopt emission standards and limitations and any other measures necessary for attainment and maintenance of national standards.
(b) Enforce applicable laws, regulations, and standards, and seek injunctive relief.
(c) Abate pollutant emissions on an emergency basis to prevent substantial endangerment to the health of persons, i.e., authority comparable to that available to the Administrator under section 305 of the Act.
(d) Prevent construction, modification, or operation of a facility, building, structure, or installation, or combination thereof, which directly or indirectly results or may result in emissions of any air pollutant at any location which will prevent the attainment or maintenance of a national standard.
(e) Obtain information necessary to determine whether air pollution sources are in compliance with applicable laws, regulations, and standards, including authority to require recordkeeping and to make inspections and conduct tests of air pollution sources.
(f) Require owners or operators of stationary sources to install, maintain, and use emission monitoring devices and to make periodic reports to the State on the nature and amounts of emissions from such stationary sources; also authority for the State to make such data available to the public as reported and as correlated with any applicable emission standards or limitations.
(a) The provisions of law or regulation which the State determines provide the authorities required under this section must be specifically identified, and copies of such laws or regulations be submitted with the plan.
(b) The plan must show that the legal authorities specified in this subpart are available to the State at the time of submission of the plan.
(c) Legal authority adequate to fulfill the requirements of § 51.230 (e) and (f) of this subpart may be delegated to the State under section 114 of the Act.
(a) A State government agency other than the State air pollution control agency may be assigned responsibility for carrying out a portion of a plan if the plan demonstrates to the Administrator's satisfaction that the State governmental agency has the legal authority necessary to carry out the portion of plan.
(b) The State may authorize a local agency to carry out a plan, or portion thereof, within such local agency's jurisdiction if—
(1) The plan demonstrates to the Administrator's satisfaction that the local agency has the legal authority necessary to implement the plan or portion of it; and
(2) This authorization does not relieve the State of responsibility under the Act for carrying out such plan, or portion thereof.
Secs. 110, 121, 174(a), 301(a), Clean Air Act, as amended (42 U.S.C. 7410, 7421, 7504, and 7601(a)).
Each State implementation plan must identify organizations, by official title, that will participate in developing, implementing, and enforcing the plan and the responsibilities of such organizations. The plan shall include any related agreements or memoranda of understanding among the organizations.
(a) For each AQCR or portion of an AQCR in which the national primary standard for carbon monoxide or ozone will not be attained by July 1, 1979, the Governor (or Governors for interstate areas) shall certify, after consultation with local officials, the organization responsible for developing the revised implementation plan or portions thereof for such AQCR.
(b)-(f) [Reserved]
(a) Each plan shall contain legally enforceable compliance schedules setting forth the dates by which all stationary and mobile sources or categories of such sources must be in compliance with any applicable requirement of the plan.
(b) The compliance schedules must contain increments of progress required by § 51.262 of this subpart.
(a) Unless EPA grants an extension under subpart R, compliance schedules designed to provide for attainment of a primary standard must—
(1) Provide for compliance with the applicable plan requirements as soon as practicable; or
(2) Provide for compliance no later than the date specified for attainment of the primary standard under;
(b) Unless EPA grants an extension under subpart R, compliance schedules designed to provide for attainment of a secondary standard must—
(1) Provide for compliance with the applicable plan requirements in a reasonable time; or
(2) Provide for compliance no later than the date specified for the attainment of the secondary standard under § 51.110(c).
(a) Any compliance schedule or revision of it extending over a period of more than one year from the date of its adoption by the State agency must provide for legally enforceable increments of progress toward compliance by each affected source or category of sources. The increments of progress must include—
(1) Each increment of progress specified in § 51.100(q); and
(2) Additional increments of progress as may be necessary to permit close and effective supervision of progress toward timely compliance.
(b) [Reserved]
Secs. 110, 301(a), 313, 319, Clean Air Act (42 U.S.C. 7410, 7601(a), 7613, 7619).
Each plan must include a description of the resources available to the State and local agencies at the date of submission of the plan and of any additional resources needed to carry out the plan during the 5-year period following its submission. The description must include projections of the extent to which resources will be acquired at 1-, 3-, and 5-year intervals.
Emission limitations and other measures necessary for attainment and maintenance of any national standard, including any measures necessary to implement the requirements of subpart L must be adopted as rules and regulations enforceable by the State agency. Copies of all such rules and regulations must be submitted with the plan. Submittal of a plan setting forth proposed rules and regulations will not satisfy the requirements of this section nor will it be considered a timely submittal.
By March 1, 1980, the State shall submit a plan revision that contains provisions for:
(a) Notifying the public on a regular basis of instances or areas in which any primary standard was exceeded during any portion of the preceeding calendar year,
(b) Advising the public of the health hazards associated with such an exceedance of a primary standard, and
(c) Increasing public awareness of:
(1) Measures which can be taken to prevent a primary standard from being exceeded, and
(2) Ways in which the public can participate in regulatory and other efforts to improve air quality.
Secs. 110, 114, 121, 160-169, 169A, and 301 of the Clean Air Act, (42 U.S.C. 7410, 7414, 7421, 7470-7479, and 7601).
(a)
(b)
(i) Each State which has a mandatory Class I Federal area identified in part 81, subpart D, of this title, and (ii) each State in which there is any source the emissions from which may reasonably be anticipated to cause or contribute to any impairment of visibility in any such area.
(2) The provisions of this subpart pertaining to implementation plans to address reasonably attributable visibility impairment are applicable to the following States:
(3) The provisions of this subpart pertaining to implementation plans to address regional haze visibility impairment are applicable to all States as defined in section 302(d) of the Clean Air Act (CAA) except Guam, Puerto Rico, American Samoa, and the Northern Mariana Islands.
At 64 FR 35763, July 1, 1999, § 51.300 was amended by revising paragraphs (a), (b)(1) introductory text, and (b)(2), and by adding paragraph (b)(3), effective Aug. 30, 1999. For the convenience of the user, the superseded text follows:
(a)
(b)
(2) The provisions of this subpart are applicable to the following States:
(i) Alabama
(ii) Alaska
(iii) Arizona
(iv) Arkansas
(v) California
(vi) Colorado
(vii) Florida
(viii) Georgia
(ix) Hawaii
(x) Idaho
(xi) Kentucky
(xii) Louisiana
(xiii) Maine
(xiv) Michigan
(xv) Minnesota
(xvi) Missouri
(xvii) Montana
(xviii) Nevada
(xix) New Hampshire
(xx) New Jersey
(xxi) New Mexico
(xxii) North Carolina
(xxiii) North Dakota
(xxiv) Oklahoma
(xxv) Oregon
(xxvi) South Carolina
(xxvii) South Dakota
(xxviii) Tennessee
(xxix) Texas
(xxx) Utah
(xxxi) Vermont
(xxxii) Virginia
(xxxiii) Virgin Islands
(xxxiv) Washington
(xxxv) West Virginia
(xxxvi) Wyoming
For purposes of this subpart:
Fossil-fuel fired steam electric plants of more than 250 million British thermal units per hour heat input,
Coal cleaning plants (thermal dryers),
Kraft pulp mills,
Portland cement plants,
Primary zinc smelters,
Iron and steel mill plants,
Primary aluminum ore reduction plants,
Primary copper smelters,
Municipal incinerators capable of charging more than 250 tons of refuse per day,
Hydrofluoric, sulfuric, and nitric acid plants,
Petroleum refineries,
Lime plants,
Phosphate rock processing plants,
Coke oven batteries,
Sulfur recovery plants,
Carbon black plants (furnace process),
Primary lead smelters,
Fuel conversion plants,
Sintering plants,
Secondary metal production facilities,
Chemical process plants,
Fossil-fuel boilers of more than 250 million British thermal units per hour heat input,
Petroleum storage and transfer facilities with a capacity exceeding 300,000 barrels,
Taconite ore processing facilities,
Glass fiber processing plants, and
Charcoal production facilities.
At 64 FR 35763, 35774, July 1, 1999, § 51.301 was amended by removing the paragraph designations, placing the defined terms in alphabetical order, revising the definitions of
(g)
(p)
(q)
(x)
(a)
(2)(i) The State, prior to adoption of any implementation plan to address reasonably attributable visibility impairment required by this subpart, must conduct one or more public hearings on such plan in accordance with § 51.102.
(ii) In addition to the requirements in § 51.102, the State must provide written notification of such hearings to each affected Federal Land Manager, and other affected States, and must state where the public can inspect a summary prepared by the Federal Land Managers of their conclusions and recommendations, if any, on the proposed plan revision.
(3) Submission of plans as required by this subpart must be conducted in accordance with the procedures in § 51.103.
(b)
(i) A list of integral vistas that are to be listed by the State for the purpose of implementing section 304,
(ii) Identification of impairment of visibility in any mandatory Class I Federal area(s), and
(iii) Identification of elements for inclusion in the visibility monitoring strategy required by section 305.
(2) The State must provide opportunity for consultation, in person and at least 60 days prior to holding any public hearing on the plan, with the Federal Land Manager on the proposed SIP revision required by this subpart. This consultation must include the opportunity for the affected Federal Land Managers to discuss their:
(i) Assessment of impairment of visibility in any mandatory Class I Federal area, and
(ii) Recommendations on the development of the long-term strategy.
(3) The plan must provide procedures for continuing consultation between the State and Federal Land Manager on the implementation of the visibility protection program required by this subpart.
(c)
(2) The plan must contain the following to address reasonably attributable impairment:
(i) A long-term (10-15 years) strategy, as specified in § 51.305 and § 51.306, including such emission limitations, schedules of compliance, and such other measures including schedules for the implementation of the elements of the long-term strategy as may be necessary to make reasonable progress toward the national goal specified in § 51.300(a).
(ii) An assessment of visibility impairment and a discussion of how each element of the plan relates to the preventing of future or remedying of existing impairment of visibility in any mandatory Class I Federal area within the State.
(iii) Emission limitations representing BART and schedules for compliance with BART for each existing stationary facility identified according to paragraph (c)(4) of this section.
(3) The plan must require each source to maintain control equipment required by this subpart and establish procedures to ensure such control equipment is properly operated and maintained.
(4) For any existing reasonably attributable visibility impairment the Federal Land Manager certifies to the State under paragraph (c)(1) of this section, at least 6 months prior to plan submission or revision:
(i) The State must identify and analyze for BART each existing stationary facility which may reasonably be anticipated to cause or contribute to impairment of visibility in any mandatory Class I Federal area where the impairment in the mandatory Class I Federal area is reasonably attributable to that existing stationary facility. The State need not consider any integral vista the Federal Land Manager did not identify pursuant to § 51.304(b) at least 6 months before plan submission.
(ii) If the State determines that technologicial or economic limitations on the applicability of measurement methodology to a particular existing stationary facility would make the imposition of an emission standard infeasible it may instead prescribe a design, equipment, work practice, or other operational standard, or combination thereof, to require the application of BART. Such standard, to the degree possible, is to set forth the emission reduction to be achieved by implementation of such design, equipment, work practice or operation, and must provide for compliance by means which achieve equivalent results.
(iii) BART must be determined for fossil-fuel fired generating plants having a total generating capacity in excess of 750 megawatts pursuant to “Guidelines for Determining Best Available Retrofit Technology for Coal-fired Power Plants and Other Existing Stationary Facilities” (1980), which is incorporated by reference, exclusive of appendix E, which was published in the
(iv) The plan must require that each existing stationary facility required to install and operate BART do so as expeditiously as practicable but in no case later than five years after plan approval.
(v) The plan must provide for a BART analysis of any existing stationary facility that might cause or contribute to impairment of visibility in any mandatory Class I Federal area identified under this paragraph (c)(4) at such times, as determined by the Administrator, as new technology for control of the pollutant becomes reasonably available if:
(A) The pollutant is emitted by that existing stationary facility,
(B) Controls representing BART for the pollutant have not previously been required under this subpart, and
(C) The impairment of visibility in any mandatory Class I Federal area is reasonably attributable to the emissions of that pollutant.
At 64 FR 35764, 35774, July 1, 1999, § 51.302 was amended in paragraph (c)(2)(i) by removing“Section 305” and adding “§ 51.305”, by removing “Section 306” and adding “§ 51.306”, by removing “Section 300(a)” and adding “§ 51.300(a)” and in paragraph (c)(4)(i) by removing “Section 304(b)” and adding “§ 51.304(b)”, and by revising the section heading, paragraphs (a), (c) introductory text, (c)(1), (c)(2) introductory text, (c)(4) introductory text, and (c)(4)(iv), effective Aug. 30, 1999. For the convenience of the user, the superseded text is set forth as follows:
(a)
(2)(i) The State, prior to adoption of any implementation plan required by this subpart, must conduct one or more public hearings on such plan in accordance with § 51.4.
(ii) In addition to the requirements in § 51.4, the State must provide written notification of such hearings to each affected Federal Land Manager, and other affected
(3) Submission of plans as required by this subpart must be conducted in accordance with the procedures in § 51.5.
(c)
(2) The plan must contain:
(4) For any existing visibility impairment the Federal Land Manager certifies to the State under paragraph (c)(1) of this section, at least 6 months prior to plan submission:
(iv) The plan must require that each existing stationary facility required to install and operate BART do so as expeditiously as practicable but in no case later than five years after plan approval.
(a)(1) Any existing stationary facility subject to the requirement under § 51.302 to install, operate, and maintain BART may apply to the Administrator for an exemption from that requirement.
(2) An application under this section must include all available documentation relevant to the impact of the source's emissions on visibility in any mandatory Class I Federal area and a demonstration by the existing stationary facility that it does not or will not, by itself or in combination with other sources, emit any air pollutant which may be reasonably anticipated to cause or contribute to a significant impairment of visibility in any mandatory Class I Federal area.
(b) Any fossil-fuel fired power plant with a total generating capacity of 750 megawatts or more may receive an exemption from BART only if the owner or operator of such power plant demonstrates to the satisfaction of the Administrator that such power plant is located at such a distance from all mandatory Class I Federal areas that such power plant does not or will not, by itself or in combination with other sources, emit any air pollutant which may reasonably be anticipated to cause or contribute to significant impairment of visibility in any such mandatory Class I Federal area.
(c) Application under this § 51.303 must be accompanied by a written concurrence from the State with regulatory authority over the source.
(d) The existing stationary facility must give prior written notice to all affected Federal Land Managers of any application for exemption under this § 51.303.
(e) The Federal Land Manager may provide an initial recommendation or comment on the disposition of such application. Such recommendation, where provided, must be part of the exemption application. This recommendation is not to be construed as the concurrence required under paragraph (h) of this section.
(f) The Administrator, within 90 days of receipt of an application for exemption from control, will provide notice of receipt of an exemption application and notice of opportunity for public hearing on the application.
(g) After notice and opportunity for public hearing, the Administrator may grant or deny the exemption. For purposes of judicial review, final EPA action on an application for an exemption under this § 51.303 will not occur until EPA approves or disapproves the State Implementation Plan revision.
(h) An exemption granted by the Administrator under this § 51.303 will be effective only upon concurrence by all affected Federal Land Managers with the Administrator's determination.
At 64 FR 35774, July 1, 1999, § 51.303 was amended in paragraph (a)(1) by removing “Section 302” and adding “§ 51.302” and in paragraphs (c), (d), (g) and (h) by removing “Section 303” and adding “§ 51.303”, effective Aug. 30, 1999.
(a) On or before December 31, 1985 the Federal Land Manager may identify any integral vista. The integral vista
(b) The Federal Land Manager must notify the State of any integral vistas identified under paragraph (a) of this section, and the reasons therefor.
(c) The State must list in its implementation plan any integral vista the Federal Land Manager identifies at least six months prior to plan submission, and must list in its implementation plan at its earliest opportunity, and in no case later than at the time of the periodic review of the SIP required by § 51.306(c), any integral vista the Federal Land Manager identifies after that time.
(d) The State need not in its implementation plan list any integral vista the indentification of which was not made in accordance with the criteria in paragraph (a) of this section. In making this finding, the State must carefully consider the expertise of the Federal Land Manager in making the judgments called for by the criteria for identification. Where the State and the Federal Land Manager disagree on the identification of any integral vista, the State must give the Federal Land Manager an opportunity to consult with the Governor of the State.
At 64 FR 35774, July 1, 1999, § 51.304 was amended in paragraph (c) by removing “Section 306(c)” and adding “§ 51.306(c)”, effective Aug. 30, 1999.
(a) For the purposes of addressing reasonably attributable visibility impairment, each State containing a mandatory Class I Federal area must include in the plan a strategy for evaluating reasonably attributable visibility impairment in any mandatory Class I Federal area by visual observation or other appropriate monitoring techniques. Such strategy must take into account current and anticipated visibility monitoring research, the availability of appropriate monitoring techniques, and such guidance as is provided by the Agency.
(b) The plan must provide for the consideration of available visibility data and must provide a mechanism for its use in decisions required by this subpart.
At 64 FR 35764, July 1, 1999, § 31.305 was amended by revising the section heading and paragraph (a), effective Aug. 30, 1999. For the convenience of the user, the superseded text follows:
(a) The State must include in the plan a strategy for evaluating visibility in any mandatory Class I Federal area by visual observation or other appropriate monitoring techniques. Such strategy must take into account current and anticipated visibility monitoring research, the availability of appropriate monitoring techniques, and such guidance as is provided by the Agency.
(a)(1) For the purposes of addressing reasonably attributable visibility impairment, each plan must include a long-term (10-15 years) strategy for making reasonable progress toward the national goal specified in § 51.300(a). This strategy must cover any existing impairment the Federal Land Manager certifies to the State at least 6 months prior to plan submission, and any integral vista of which the Federal Land Manager notifies the State at least 6 months prior to plan submission.
(2) A long-term strategy must be developed for each mandatory Class I Federal area located within the State and each mandatory Class I Federal area located outside the State which may be affected by sources within the State. This does not preclude the development of a single comprehensive plan for all such areas.
(3) The plan must set forth with reasonable specificity why the long-term strategy is adequate for making reasonable progress toward the national
(b) The State must coordinate its long-term strategy for an area with existing plans and goals, including those provided by the affected Federal Land Managers, that may affect impairment of visibility in any mandatory Class I Federal area.
(c) The plan must provide for periodic review and revision, as appropriate, of the long-term strategy for addressing reasonably attributable visibility impairment. The plan must provide for such periodic review and revision not less frequently than every 3 years until the date of submission of the State's first plan addressing regional haze visibility impairment in accordance with § 51.308(b) and (c). On or before this date, the State must revise its plan to provide for review and revision of a coordinated long-term strategy for addressing reasonably attributable and regional haze visibility impairment, and the State must submit the first such coordinated long-term strategy. Future coordinated long-term strategies must be submitted consistent with the schedule for periodic progress reports set forth in § 51.308(g). Until the State revises its plan to meet this requirement, the State must continue to comply with existing requirements for plan review and revision, and with all emission management requirements in the plan to address reasonably attributable impairment. This requirement does not affect any preexisting deadlines for State submittal of a long-term strategy review (or element thereof) between August 30, 1999, and the date required for submission of the State's first regional haze plan. In addition, the plan must provide for review of the long-term strategy as it applies to reasonably attributable impairment, and revision as appropriate, within 3 years of State receipt of any certification of reasonably attributable impairment from a Federal Land Manager. The review process must include consultation with the appropriate Federal Land Managers, and the State must provide a report to the public and the Administrator on progress toward the national goal. This report must include an assessment of:
(1) The progress achieved in remedying existing impairment of visibility in any mandatory Class I Federal area;
(2) The ability of the long-term strategy to prevent future impairment of visibility in any mandatory Class I Federal area;
(3) Any change in visibility since the last such report, or, in the case of the first report, since plan approval;
(4) Additional measures, including the need for SIP revisions, that may be necessary to assure reasonable progress toward the national visibility goal;
(5) The progress achieved in implementing BART and meeting other schedules set forth in the long-term strategy;
(6) The impact of any exemption granted under § 51.303;
(7) The need for BART to remedy existing visibility impairment of any integral vista listed in the plan since the last such report, or, in the case of the first report, since plan approval.
(d) The long-term strategy must provide for review of the impacts from any new major stationary source or major modifications on visibility in any mandatory Class I Federal area. This review of major stationary sources or major modifications must be in accordance with § 51.307, § 51.166, § 51.160, and any other binding guidance provided by the Agency insofar as these provisions pertain to protection of visibility in any mandatory Class I Federal areas.
(e) The State must consider, at a minimum, the following factors during the development of its long-term strategy:
(1) Emission reductions due to ongoing air pollution control programs,
(2) Additional emission limitations and schedules for compliance,
(3) Measures to mitigate the impacts of construction activities,
(4) Source retirement and replacement schedules,
(5) Smoke management techniques for agricultural and forestry management purposes including such plans as currently exist within the State for these purposes, and
(6) Enforceability of emission limitations and control measures.
(f) The plan must discuss the reasons why the above and other reasonable measures considered in the development of the long-term strategy were or were not adopted as part of the long-term strategy.
(g) The State, in developing the long-term strategy, must take into account the effect of new sources, and the costs of compliance, the time necessary for compliance, the energy and nonair quality environmental impacts of compliance, and the remaining useful life of any affected existing source and equipment therein.
At 64 FR 35764, 35774, July 1, 1999, § 51.306 was amended in paragraph (a)(1) by removing “Section 300(a)” and adding “§ 51.300(a)” and paragraph (c)(6) was amended by removing “Section 303” and adding “§ 51.303”, and by revising the section heading, paragraph (a)(1), paragraph (c) introductory text, and paragraph (d), effective Aug. 30, 1999. For the convenience of the user, the superseded text follows:
(a)(1) Each plan must include a long-term (10-15 years) strategy for making reasonable progress toward the national goal specified in section 300(a). This strategy must cover any existing impairment the Federal Land Manager certifies to the State at least 6 months prior to plan submission, and any integral vista of which the Federal Land Manager notifies the State at least 6 months prior to plan submission.
(c) The plan must provide for periodic review and revision, as appropriate, of the long-term strategy not less frequent than every three years. This review process must include consultation with the appropriate Federal Land Managers, and the State must provide a report to the public and the Administrator on progress toward the national goal. This report must include an assessment of:
(d) The long-term strategy must provide for review of the impacts from any new major stationary source or major modifications on visibility in any mandatory Class I Federal area. This review of major stationary sources or major modifications must be in accordance with section 307, § 51.24, § 51.18 and any other binding guidance provided by the Agency insofar as these provisions pertain to protection of visibility in any mandatory Class I Federal areas.
(a) For purposes of new source review of any new major stationary source or major modification that would be constructed in an area that is designated attainment or unclassified under section 107(d)(1)(D) or (E) of the CAA, the State plan must, in any review under § 51.166 with respect to visibility protection and analyses, provide for:
(1) Written notification of all affected Federal Land Managers of any proposed new major stationary source or major modification that may affect visibility in any Federal Class I area. Such notification must be made in writing and include a copy of all information relevant to the permit application within 30 days of receipt of and at least 60 days prior to public hearing by the State on the application for permit to construct. Such notification must include an analysis of the anticipated impacts on visibility in any Federal Class I area,
(2) Where the State requires or receives advance notification (e.g. early consultation with the source prior to submission of the application or notification of intent to monitor under § 51.166) of a permit application of a source that may affect visibility the State must notify all affected Federal Land Managers within 30 days of such advance notification, and
(3) Consideration of any analysis performed by the Federal Land Manager, provided within 30 days of the notification and analysis required by paragraph (a)(1) of this section, that such proposed new major stationary source or major modification may have an adverse impact on visibility in any Federal Class I area. Where the State finds that such an analysis does not demonstrate to the satisfaction of the State that an adverse impact will result in the Federal Class I area, the State must, in the notice of public hearing, either explain its decision or give notice as to where the explanation can be obtained.
(b) The plan shall also provide for the review of any new major stationary source or major modification:
(1) That may have an impact on any integral vista of a mandatory Class I Federal area, if it is identified in accordance with § 51.304 by the Federal Land Manager at least 12 months before submission of a complete permit application, except where the Federal Land Manager has provided notice and opportunity for public comment on the integral vista in which case the review must include impacts on any integral vista identified at least 6 months prior to submission of a complete permit application, unless the State determines under § 51.304(d) that the identification was not in accordance with the identification criteria, or
(2) That proposes to locate in an area classified as nonattainment under section 107(d)(1)(A), (B), or (C) of the Clean Air Act that may have an impact on visibility in any mandatory Class I Federal area.
(c) Review of any major stationary source or major modification under paragraph (b) of this section, shall be conducted in accordance with paragraph (a) of this section, and § 51.166(o), (p)(1) through (2), and (q). In conducting such reviews the State must ensure that the source's emissions will be consistent with making reasonable progress toward the national visibility goal referred to in § 51.300(a). The State may take into account the costs of compliance, the time necessary for compliance, the energy and nonair quality environmental impacts of compliance, and the useful life of the source.
(d) The State may require monitoring of visibility in any Federal Class I area near the proposed new stationary source or major modification for such purposes and by such means as the State deems necessary and appropriate.
At 64 FR 35765, 35774, July 1, 1999, § 51.307 was amended in paragraph (b)(1) by removing “Section 304” and “Section 304(d)” and adding “§ 51.304” and “§ 51.304(d)” respectively; and paragraph (c) was amended by removing “Section 300(a)” and adding “§ 51.303(a)“; and revising paragraph (a) introductory text, (a)(2), and (c), effective Aug. 30, 1999. For the convenience of the user, the superseded text is set out as follows:
(a) For purposes of new source review of any new major stationary source or major modification that would be constructed in an area that is designated attainment or unclassified under section 107(d)(1)(D) or (E) of the Clean Air Act, the State plan must, in any review under § 51.24 with respect to visibility protection and analyses, provide for:
(2) Where the State requires or receives advance notification (e.g. early consultation with the source prior to submission of the application or notification of intent to monitor under § 51.24) of a permit application of a source that may affect visibility the State must notify all affected Federal Land Managers within 30 days of such advance notification, and
(c) Review of any major stationary source or major modification under paragraph (b) of this section, shall be conducted in accordance with paragraph (a) of this section, and § 51.24(o), (p) (1) through (2), and (q). In conducting such reviews the State must ensure that the source's emissions will be consistent with making reasonable progress toward the national visibility goal referred to in § 300(a). The State may take into account the costs of compliance, the time necessary for compliance, the energy and nonair quality environmental impacts of compliance, and the useful life of the source.
(a)
(b)
(1) For any area designated as attainment or unclassifiable for the national ambient air quality standard (NAAQS) for fine particulate matter (PM
(2) For any area designated as nonattainment for the PM
(c)
(1) The State must submit an implementation plan by the earliest date by which an implementation plan would be due for any area of the State under paragraph (b) of this section. This implementation plan must contain the following:
(i) A demonstration of ongoing participation in a regional planning process to address regional haze, and an agreement by the State to continue participating with one or more other States in such a process for the development of this and future implementation plan revisions;
(ii) A showing, based on available inventory, monitoring, or modeling information, that emissions from within the State contribute to visibility impairment in a mandatory Class I Federal Area outside the State, or that emissions from another State contribute to visibility impairment in any mandatory Class I Federal area within the State.
(iii) A description of the regional planning process, including a list of the States which have agreed to work together to address regional haze in a region (i.e., the regional planning group), the goals, objectives, management, and decisionmaking structure of the regional planning group, deadlines for completing significant technical analyses and developing emission management strategies, and a schedule for State review and adoption of regulations implementing the recommendations of the regional group;
(iv) A commitment by the State to submit an implementation plan revision addressing the requirements in paragraphs (d) and (e) of this section by the date specified in paragraph (c)(2) of this section. In addition, the State must commit to develop its plan revision in coordination with the other States participating in the regional planning process, and to fully address the recommendations of the regional planning group.
(v) A list of all BART-eligible sources within the State.
(2) The State must submit an implementation plan revision addressing the requirements in paragraphs (d) and (e) of this section by the latest date an area within the planning region would be required to submit an implementation plan under paragraph (b) of this section, but in any event, no later than December 31, 2008.
(d)
(1)
(i) In establishing a reasonable progress goal for any mandatory Class
(A) Consider the costs of compliance, the time necessary for compliance, the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any potentially affected sources, and include a demonstration showing how these factors were taken into consideration in selecting the goal.
(B) Analyze and determine the rate of progress needed to attain natural visibility conditions by the year 2064. To calculate this rate of progress, the State must compare baseline visibility conditions to natural visibility conditions in the mandatory Federal Class I area and determine the uniform rate of visibility improvement (measured in deciviews) that would need to be maintained during each implementation period in order to attain natural visibility conditions by 2064. In establishing the reasonable progress goal, the State must consider the uniform rate of improvement in visibility and the emission reduction measures needed to achieve it for the period covered by the implementation plan.
(ii) For the period of the implementation plan, if the State establishes a reasonable progress goal that provides for a slower rate of improvement in visibility than the rate that would be needed to attain natural conditions by 2064, the State must demonstrate, based on the factors in paragraph (d)(1)(i)(A) of this section, that the rate of progress for the implementation plan to attain natural conditions by 2064 is not reasonable; and that the progress goal adopted by the State is reasonable. The State must provide to the public for review as part of its implementation plan an assessment of the number of years it would take to attain natural conditions if visibility improvement continues at the rate of progress selected by the State as reasonable.
(iii) In determining whether the State's goal for visibility improvement provides for reasonable progress towards natural visibility conditions, the Administrator will evaluate the demonstrations developed by the State pursuant to paragraphs (d)(1)(i) and (d)(1)(ii) of this section.
(iv) In developing each reasonable progress goal, the State must consult with those States which may reasonably be anticipated to cause or contribute to visibility impairment in the mandatory Class I Federal area. In any situation in which the State cannot agree with another such State or group of States that a goal provides for reasonable progress, the State must describe in its submittal the actions taken to resolve the disagreement. In reviewing the State's implementation plan submittal, the Administrator will take this information into account in determining whether the State's goal for visibility improvement provides for reasonable progress towards natural visibility conditions.
(v) The reasonable progress goals established by the State are not directly enforceable but will be considered by the Administrator in evaluating the adequacy of the measures in the implementation plan to achieve the progress goal adopted by the State.
(vi) The State may not adopt a reasonable progress goal that represents less visibility improvement than is expected to result from implementation of other requirements of the CAA during the applicable planning period.
(2)
(i) Baseline visibility conditions for the most impaired and least impaired days. The period for establishing baseline visibility conditions is 2000 to 2004. Baseline visibility conditions must be calculated, using available monitoring data, by establishing the average degree of visibility impairment for the most and least impaired days for each calendar year from 2000 to 2004. The baseline visibility conditions are the average of these annual values. For mandatory Class I Federal areas without onsite monitoring data for 2000-2004, the State must establish baseline values using the most representative available monitoring data for 2000-2004, in consultation with the Administrator or his or her designee;
(ii) For an implementation plan that is submitted by 2003, the period for establishing baseline visibility conditions for the period of the first long-term strategy is the most recent 5-year period for which visibility monitoring data are available for the mandatory Class I Federal areas addressed by the plan. For mandatory Class I Federal areas without onsite monitoring data, the State must establish baseline values using the most representative available monitoring data, in consultation with the Administrator or his or her designee;
(iii) Natural visibility conditions for the most impaired and least impaired days. Natural visibility conditions must be calculated by estimating the degree of visibility impairment existing under natural conditions for the most impaired and least impaired days, based on available monitoring information and appropriate data analysis techniques; and
(iv)(A) For the first implementation plan addressing the requirements of paragraphs (d) and (e) of this section, the number of deciviews by which baseline conditions exceed natural visibility conditions for the most impaired and least impaired days; or
(B) For all future implementation plan revisions, the number of deciviews by which current conditions, as calculated under paragraph (f)(1) of this section, exceed natural visibility conditions for the most impaired and least impaired days.
(3)
(i) Where the State has emissions that are reasonably anticipated to contribute to visibility impairment in any mandatory Class I Federal area located in another State or States, the State must consult with the other State(s) in order to develop coordinated emission management strategies. The State must consult with any other State having emissions that are reasonably anticipated to contribute to visibility impairment in any mandatory Class I Federal area within the State.
(ii) Where other States cause or contribute to impairment in a mandatory Class I Federal area, the State must demonstrate that it has included in its implementation plan all measures necessary to obtain its share of the emission reductions needed to meet the progress goal for the area. If the State has participated in a regional planning process, the State must ensure it has included all measures needed to achieve its apportionment of emission reduction obligations agreed upon through that process.
(iii) The State must document the technical basis, including modeling, monitoring and emissions information, on which the State is relying to determine its apportionment of emission reduction obligations necessary for achieving reasonable progress in each mandatory Class I Federal area it affects. The State may meet this requirement by relying on technical analyses developed by the regional planning organization and approved by all State participants. The State must identify the baseline emissions inventory on which its strategies are based. The baseline emissions inventory year is presumed to be the most recent year of the consolidate periodic emissions inventory.
(iv) The State must identify all anthropogenic sources of visibility impairment considered by the State in developing its long-term strategy. The State should consider major and minor stationary sources, mobile sources, and area sources.
(v) The State must consider, at a minimum, the following factors in developing its long-term strategy:
(A) Emission reductions due to ongoing air pollution control programs, including measures to address reasonably attributable visibility impairment;
(B) Measures to mitigate the impacts of construction activities;
(C) Emissions limitations and schedules for compliance to achieve the reasonable progress goal;
(D) Source retirement and replacement schedules;
(E) Smoke management techniques for agricultural and forestry management purposes including plans as currently exist within the State for these purposes;
(F) Enforceability of emissions limitations and control measures; and
(G) The anticipated net effect on visibility due to projected changes in point, area, and mobile source emissions over the period addressed by the long-term strategy.
(4)
(i) The establishment of any additional monitoring sites or equipment needed to assess whether reasonable progress goals to address regional haze for all mandatory Class I Federal areas within the State are being achieved.
(ii) Procedures by which monitoring data and other information are used in determining the contribution of emissions from within the State to regional haze visibility impairment at mandatory Class I Federal areas both within and outside the State.
(iii) For a State with no mandatory Class I Federal areas, procedures by which monitoring data and other information are used in determining the contribution of emissions from within the State to regional haze visibility impairment at mandatory Class I Federal areas in other States.
(iv) The implementation plan must provide for the reporting of all visibility monitoring data to the Administrator at least annually for each mandatory Class I Federal area in the State. To the extent possible, the State should report visibility monitoring data electronically.
(v) A statewide inventory of emissions of pollutants that are reasonably anticipated to cause or contribute to visibility impairment in any mandatory Class I Federal area. The inventory must include emissions for a baseline year, emissions for the most recent year for which data are available, and estimates of future projected emissions. The State must also include a commitment to update the inventory periodically.
(vi) Other elements, including reporting, recordkeeping, and other measures, necessary to assess and report on visibility.
(e)
(1) To address the requirements for BART, the State must submit an implementation plan containing the following plan elements and include documentation for all required analyses:
(i) A list of all BART-eligible sources within the State.
(ii) A determination of BART for each BART-eligible source in the State that emits any air pollutant which may reasonably be anticipated to cause or contribute to any impairment of visibility in any mandatory Class I Federal area. All such sources are subject to BART. This determination must be based on the following analyses:
(A) An analysis of the best system of continuous emission control technology available and associated emission reductions achievable for each BART-eligible source within the State subject to BART. In this analysis, the State must take into consideration the technology available, the costs of compliance, the energy and nonair quality environmental impacts of compliance, any pollution control equipment in use at the source, and the remaining useful life of the source; and
(B) An analysis of the degree of visibility improvement that would be achieved in each mandatory Class I Federal area as a result of the emission reductions achievable from all sources subject to BART located within the region that contributes to visibility impairment in the Class I area, based on the analysis conducted under paragraph (e)(1)(ii)(A) of this section.
(iii) If the State determines in establishing BART that technological or economic limitations on the applicability of measurement methodology to a particular source would make the imposition of an emission standard infeasible, it may instead prescribe a design, equipment, work practice, or other operational standard, or combination thereof, to require the application of BART. Such standard, to the degree possible, is to set forth the emission reduction to be achieved by implementation of such design, equipment, work practice or operation, and must provide for compliance by means which achieve equivalent results.
(iv) A requirement that each source subject to BART be required to install and operate BART as expeditiously as practicable, but in no event later than 5 years after approval of the implementation plan revision.
(v) A requirement that each source subject to BART maintain the control equipment required by this subpart and establish procedures to ensure such equipment is properly operated and maintained.
(2) A State may opt to implement an emissions trading program or other alternative measure rather than to require sources subject to BART to install, operate, and maintain BART. To do so, the State must demonstrate that this emissions trading program or other alternative measure will achieve greater reasonable progress than would be achieved through the installation and operation of BART. To make this demonstration, the State must submit an implementation plan containing the following plan elements and include documentation for all required analyses:
(i) A demonstration that the emissions trading program or other alternative measure will achieve greater reasonable progress than would have resulted from the installation and operation of BART at all sources subject to BART in the State. This demonstration must be based on the following:
(A) A list of all BART-eligible sources within the State.
(B) An analysis of the best system of continuous emission control technology available and associated emission reductions achievable for each source within the State subject to BART. In this analysis, the State must take into consideration the technology available, the costs of compliance, the energy and nonair quality environmental impacts of compliance, any pollution control equipment in use at the source, and the remaining useful life of the source. The best system of continuous emission control technology and the above factors may be determined on a source category basis. The State may elect to consider both source-specific and category-wide information, as appropriate, in conducting its analysis.
(C) An analysis of the degree of visibility improvement that would be achieved in each mandatory Class I Federal area as a result of the emission reductions achievable from all such sources subject to BART located within the region that contributes to visibility impairment in the Class I area, based on the analysis conducted under paragraph (e)(2)(i)(B) of this section.
(ii) A demonstration that the emissions trading program or alternative measure will apply, at a minimum, to all BART-eligible sources in the State. Those sources having a federally enforceable emission limitation determined by the State and approved by EPA as meeting BART in accordance with § 51.302(c) or paragraph (e)(1) of this section do not need to meet the requirements of the emissions trading
(iii) A requirement that all necessary emission reductions take place during the period of the first long-term strategy for regional haze. To meet this requirement, the State must provide a detailed description of the emissions trading program or other alternative measure, including schedules for implementation, the emission reductions required by the program, all necessary administrative and technical procedures for implementing the program, rules for accounting and monitoring emissions, and procedures for enforcement.
(iv) A demonstration that the emission reductions resulting from the emissions trading program or other alternative measure will be surplus to those reductions resulting from measures adopted to meet requirements of the CAA as of the baseline date of the SIP.
(v) At the State's option, a provision that the emissions trading program or other alternative measure may include a geographic enhancement to the program to address the requirement under § 51.302(c) related to BART for reasonably attributable impairment from the pollutants covered under the emissions trading program or other alternative measure.
(3) After a State has met the requirements for BART or implemented emissions trading program or other alternative measure that achieve more reasonable progress than the installation and operation of BART, BART-eligible sources will be subject to the requirements of paragraph (d) of this section in the same manner as other sources.
(4) Any BART-eligible facility subject to the requirement under paragraph (e) of this section to install, operate, and maintain BART may apply to the Administrator for an exemption from that requirement. An application for an exemption will be subject to the requirements of § 51.303 (a)(2) through (h).
(f)
(1) Current visibility conditions for the most impaired and least impaired days, and actual progress made towards natural conditions during the previous implementation period. The period for calculating current visibility conditions is the most recent five year period preceding the required date of the implementation plan submittal for which data are available. Current visibility conditions must be calculated based on the annual average level of visibility impairment for the most and least impaired days for each of these five years. Current visibility conditions are the average of these annual values.
(2) The effectiveness of the long-term strategy for achieving reasonable progress goals over the prior implementation period(s); and
(3) Affirmation of, or revision to, the reasonable progress goal in accordance with the procedures set forth in paragraph (d)(1) of this section. If the State established a reasonable progress goal for the prior period which provided a slower rate of progress than that needed to attain natural conditions by the year 2064, the State must evaluate and determine the reasonableness, based on the factors in paragraph (d)(1)(i)(A) of this section, of additional measures that could be adopted to achieve the degree of visibility improvement projected by the analysis contained in the first implementation plan described in paragraph (d)(1)(i)(B) of this section.
(g)
(1) A description of the status of implementation of all measures included in the implementation plan for achieving reasonable progress goals for mandatory Class I Federal areas both within and outside the State.
(2) A summary of the emissions reductions achieved throughout the State through implementation of the measures described in paragraph (g)(1) of this section.
(3) For each mandatory Class I Federal area within the State, the State must assess the following visibility conditions and changes, with values for most impaired and least impaired days expressed in terms of 5-year averages of these annual values.
(i) The current visibility conditions for the most impaired and least impaired days;
(ii) The difference between current visibility conditions for the most impaired and least impaired days and baseline visibility conditions;
(iii) The change in visibility impairment for the most impaired and least impaired days over the past 5 years;
(4) An analysis tracking the change over the past 5 years in emissions of pollutants contributing to visibility impairment from all sources and activities within the State. Emissions changes should be identified by type of source or activity. The analysis must be based on the most recent updated emissions inventory, with estimates projected forward as necessary and appropriate, to account for emissions changes during the applicable 5-year period.
(5) An assessment of any significant changes in anthropogenic emissions within or outside the State that have occurred over the past 5 years that have limited or impeded progress in reducing pollutant emissions and improving visibility.
(6) An assessment of whether the current implementation plan elements and strategies are sufficient to enable the State, or other States with mandatory Federal Class I areas affected by emissions from the State, to meet all established reasonable progress goals.
(7) A review of the State's visibility monitoring strategy and any modifications to the strategy as necessary.
(h)
(1) If the State determines that the existing implementation plan requires no further substantive revision at this time in order to achieve established goals for visibility improvement and emissions reductions, the State must provide to the Administrator a negative declaration that further revision of the existing implementation plan is not needed at this time.
(2) If the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from sources in another State(s) which participated in a regional planning process, the State must provide notification to the Administrator and to the other State(s) which participated in the regional planning process with the States. The State must also collaborate with the other State(s) through the regional planning process for the purpose of developing additional strategies to address the plan's deficiencies.
(3) Where the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from sources in another country, the State shall provide notification, along with available information, to the Administrator.
(4) Where the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from sources within the State, the State shall revise
(i)
(1) By November 29, 1999, the State must identify in writing to the Federal Land Managers the title of the official to which the Federal Land Manager of any mandatory Class I Federal area can submit any recommendations on the implementation of this subpart including, but not limited to:
(i) Identification of impairment of visibility in any mandatory Class I Federal area(s); and
(ii) Identification of elements for inclusion in the visibility monitoring strategy required by § 51.305 and this section.
(2) The State must provide the Federal Land Manager with an opportunity for consultation, in person and at least 60 days prior to holding any public hearing on an implementation plan (or plan revision) for regional haze required by this subpart. This consultation must include the opportunity for the affected Federal Land Managers to discuss their:
(i) Assessment of impairment of visibility in any mandatory Class I Federal area; and
(ii) Recommendations on the development of the reasonable progress goal and on the development and implementation of strategies to address visibility impairment.
(3) In developing any implementation plan (or plan revision), the State must include a description of how it addressed any comments provided by the Federal Land Managers.
(4) The plan (or plan revision) must provide procedures for continuing consultation between the State and Federal Land Manager on the implementation of the visibility protection program required by this subpart, including development and review of implementation plan revisions and 5-year progress reports, and on the implementation of other programs having the potential to contribute to impairment of visibility in mandatory Class I Federal areas.
At 64 FR 35765, July 1, 1999, § 51.308 was added, effective Aug. 30, 1999.
(a)
(b)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(c)
(d)
(1)
(2)
(3)
(i) An identification of clean-air corridors. The EPA will evaluate the State's identification of such corridors based upon the reports of the Commission's Meteorology Subcommittee and any future updates by a successor organization;
(ii) Within areas that are clean-air corridors, an identification of patterns of growth or specific sites of growth that could cause, or are causing, significant emissions increases that could have, or are having, visibility impairment at one or more of the 16 Class I areas.
(iii) In areas outside of clean-air corridors, an identification of significant emissions growth that could begin, or is beginning, to impair the quality of air in the corridor and thereby lead to visibility degradation for the least-impaired days in one or more of the 16 Class I areas.
(iv) If impairment of air quality in clean air corridors is identified pursuant to paragraphs (d)(3)(ii) and (iii) of this section, an analysis of the effects
(v) A determination of whether other clean air corridors exist for any of the 16 Class I areas. For any such clean air corridors, an identification of the necessary measures to protect against future degradation of air quality in any of the 16 Class I areas.
(4)
(i) Monitoring and reporting of sulfur dioxide emissions. The plan submission must include provisions requiring the monitoring and reporting of actual stationary source sulfur dioxide emissions within the State. The monitoring and reporting data must be sufficient to determine whether a 13 percent reduction in actual stationary source sulfur dioxide emissions has occurred between the years 1990 and 2000, and whether milestones required by paragraph (f)(1)(i) of this section have been achieved for the transport region. The plan submission must provide for reporting of these data by the State to the Administrator. Where procedures developed under paragraph (f)(1)(ii) of this section and agreed upon by the State include reporting to a regional planning organization, the plan submission must provide for reporting to the regional planning body in addition to the Administrator.
(ii) Criteria and procedures for a market trading program. The plan must include the criteria and procedures for activating a market trading program or other program consistent with paragraph (f)(1)(i) of this section if an applicable regional milestone is exceeded, procedures for operation of the program, and implementation plan assessments and provisions for implementation plan assessments of the program in the years 2008, 2013, and 2018.
(iii) Provisions for activating a market trading program. Provisions to activate the market trading program or other program within 12 months after the emissions for the region are determined to exceed the applicable emission reduction milestone, and to assure that all affected sources are in compliance with allocation and other requirements within 5 years after the emissions for the region are determined to exceed the applicable emission reduction milestone.
(iv) Provisions for market trading program compliance reporting. If the market trading program has been activated, the plan submission must include provisions requiring the State to provide annual reports assuring that all sources are in compliance with applicable requirements of the market trading program.
(v) Provisions for stationary source NO
(5)
(i) Statewide inventories of current annual emissions and projected future annual emissions of VO
(ii) A determination whether mobile source emissions in any areas of the State contribute significantly to visibility impairment in any of the 16 Class I Areas, based on the statewide
(iii) For States with areas in which mobile source emissions are found to contribute significantly to visibility impairment in any of the 16 Class I areas:
(A) The establishment and documentation of a mobile source emissions budget for any such area, including provisions requiring the State to restrict the annual VOC, NO
(B) An emission tracking system providing for reporting of annual mobile source emissions from the State in the periodic implementation plan revisions required by paragraph (d)(10) of this section. The emission tracking system must be sufficient to determine the States’ contribution toward the Commission's objective of reducing emissions from mobile sources by 2005 or an alternate year that is determined by the State to represent the year during which mobile source emissions will be at their lowest levels within the State, and to ensure that mobile source emissions do not increase thereafter.
(iv) Interim reports to EPA and the public in years 2003, 2008, 2013, and 2018 on the implementation status of the regional and local strategies recommended by the Commission Report to address mobile source emissions.
(6)
(i) Documentation that all Federal, State, and private prescribed fire programs within the State evaluate and address the degree visibility impairment from smoke in their planning and application. In addition the plan must include smoke management programs that include all necessary components including, but not limited to, actions to minimize emissions, evaluation of smoke dispersion, alternatives to fire, public notification, air quality monitoring, surveillance and enforcement, and program evaluation.
(ii) A statewide inventory and emissions tracking system (spatial and temporal) of VOC, NO
(iii) Identification and removal wherever feasible of any administrative barriers to the use of alternatives to burning in Federal, State, and private prescribed fire programs within the State.
(iv) Enhanced smoke management programs for fire that consider visibility effects, not only health and nuisance objectives, and that are based on the criteria of efficiency, economics, law, emission reduction opportunities, land management objectives, and reduction of visibility impact.
(v) Establishment of annual emission goals for fire, excluding wildfire, that will minimize emission increases from fire to the maximum extent feasible and that are established in cooperation with States, tribes, Federal land management agencies, and private entities.
(7)
(8)
(i) An initial summary of all pollution prevention programs currently in place, an inventory of all renewable energy generation capacity and production in use, or planned as of the year 2002 (expressed in megawatts and megawatt-hours), the total energy generation capacity and production for the State, the percent of the total that is renewable energy, and the State's anticipated contribution toward the renewable energy goals for 2005 and 2015, as provided in paragraph (d)(8)(vi) of this section.
(ii) Programs to provide incentives that reward efforts that go beyond compliance and/or achieve early compliance with air-pollution related requirements.
(iii) Programs to preserve and expand energy conservation efforts.
(iv) The identification of specific areas where renewable energy has the potential to supply power where it is now lacking and where renewable energy is most cost-effective.
(v) Projections of the short- and long-term emissions reductions, visibility improvements, cost savings, and secondary benefits associated with the renewable energy goals, energy efficiency and pollution prevention activities.
(vi) A description of the programs relied on to achieve the State's contribution toward the Commission's goal that renewable energy will comprise 10 percent of the regional power needs by 2005 and 20 percent by 2015, and a demonstration of the progress toward achievement of the renewable energy goals in the years 2003, 2008, 2013, and 2018. This description must include documentation of the potential for renewable energy resources, the percentage of renewable energy associated with new power generation projects implemented or planned, and the renewable energy generation capacity and production in use and planned in the State. To the extent that it is not feasible for a State to meet its contribution to the regional renewable energy goals, the State must identify in the progress reports the measures implemented to achieve its contribution and explain why meeting the State's contribution was not feasible.
(9)
(10)
(i) The report will assess the area for reasonable progress as provided in this section for mandatory Class I Federal area(s) located within the State and for mandatory Class I Federal area(s) located outside the State which may be affected by emissions from within the State. This demonstration may be based on assessments conducted by the States and/or a regional planning body. The progress reports must contain at a minimum the following elements:
(A) A description of the status of implementation of all measures included in the implementation plan for achieving reasonable progress goals for mandatory Class I Federal areas both within and outside the State.
(B) A summary of the emissions reductions achieved throughout the State through implementation of the measures described in paragraph (d)(10)(i)(A) of this section.
(C) For each mandatory Class I Federal area within the State, an assessment of the following: the current visibility conditions for the most impaired and least impaired days; the difference between current visibility conditions for the most impaired and least impaired days and baseline visibility conditions; the change in visibility impairment for the most impaired and least impaired days over the past 5 years.
(D) An analysis tracking the change over the past 5 years in emissions of pollutants contributing to visibility impairment from all sources and activities within the State. Emissions changes should be identified by type of source or activity. The analysis must be based on the most recent updated emissions inventory, with estimates projected forward as necessary and appropriate, to account for emissions changes during the applicable 5-year period.
(E) An assessment of any significant changes in anthropogenic emissions within or outside the State that have occurred over the past 5 years that have limited or impeded progress in reducing pollutant emissions and improving visibility.
(F) An assessment of whether the current implementation plan elements and strategies are sufficient to enable the State, or other States with mandatory Federal Class I areas affected by emissions from the State, to meet all established reasonable progress goals.
(G) A review of the State's visibility monitoring strategy and any modifications to the strategy as necessary.
(ii) At the same time the State is required to submit any 5-year progress report to EPA in accordance with paragaph (d)(10)(i) of this section, the State must also take one of the following actions based upon the information presented in the progress report:
(A) If the State determines that the existing implementation plan requires no further substantive revision at this time in order to achieve established goals for visibility improvement and emissions reductions, the State must provide to the Administrator a negative declaration that further revision of the existing implementation plan is not needed at this time.
(B) If the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from sources in another State(s) which participated in a regional planning process, the State must provide notification to the Administrator and to the other State(s) which participated in the regional planning process with the States. The State must also collaborate with the other State(s) through the regional planning process for the purpose of developing additional strategies to address the plan's deficiencies.
(C) Where the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from sources in another country, the State shall provide notification, along with available information, to the Administrator.
(D) Where the State determines that the implementation plan is or may be inadequate to ensure reasonable progress due to emissions from within the State, the State shall develop additional strategies to address the plan deficiencies and revise the implementation plan no later than one year from the date that the progress report was due.
(11)
(12)
(e)
(f)
(i) The annex must contain quantitative emission reduction milestones for stationary source sulfur dioxide emissions for the reporting years 2003, 2008, 2013 and 2018. The milestones must provide for steady and continuing emission reductions for the 2003-2018 time period consistent with the Commission's definition of reasonable progress, its goal of 50 to 70 percent reduction in sulfur dioxide emissions from 1990 actual emission levels by 2040, applicable requirements under the CAA, and the timing of implementation plan assessments of progress and identification of deficiencies which will be due in the years 2008, 2013, and 2018. The emission reduction milestones must be shown to provide for greater reasonable progress than would be achieved by application of best available retrofit technology (BART) pursuant to § 51.308(e)(2) and would be approvable in lieu of BART.
(ii) The annex must contain documentation of the market trading program or other programs to be implemented pursuant to paragraph (d)(4) of this section if current programs and voluntary measures are not sufficient to meet the required emission reduction milestones. This documentation must include model rules, memoranda of understanding, and other documentation describing in detail how emission reduction progress will be monitored, what conditions will require the market trading program to be activated, how allocations will be performed, and how the program will operate.
(2) The Commission may elect, at the same time it submits the annex, to make recommendations intended to demonstrate reasonable progress for other mandatory Class I areas (beyond the original 16) within the Transport Region States, including the technical and policy justification for these additional mandatory Class I Federal areas in accordance with the provisions of paragraph (g) of this section.
(3) The EPA will publish the annex upon receipt. If EPA finds that the annex meets the requirements of paragraph (f)(1) of this section and assures reasonable progress, then, after public notice and comment, will amend the requirements of paragraph (d)(4) of this section to incorporate the provisions of the annex within 1 year after EPA receives the annex. If EPA finds that the annex does not meet the requirements of paragraph (f)(1) of this section, or does not assure reasonable progress, or if EPA finds that the annex is not received, then each Transport Region State must submit an implementation plan for regional haze meeting all of the requirements of § 51.308.
(4) In accordance with the provisions under paragraph (f)(1) of this section, the annex may include a geographic enhancement to the program provided for in paragraph (d)(4) of this section to address the requirement under § 51.302(c) related to Best Available Retrofit Technology for reasonably attributable impairment from the pollutants covered by the milestones or the backstop market trading program. The geographic enhancement program may include an appropriate level of reasonably attributable impairment which may require additional emission reductions over and above those achieved under the milestones defines in paragraph (f)(1)(i) of this section.
(g)
(1) In the plan submitted for the 16 Class I areas no later than December 31, 2003, a declaration indicating whether other Class I areas will be addressed under § 51.308 or paragraphs (g)(2) and (3) of this section.
(2) In a plan submitted no later than December 31, 2008, provide a demonstration of expected visibility conditions for the most impaired and least impaired days at the additional mandatory Class I Federal area(s) based on emissions projections from the long-term strategies in the implementation plan. This demonstration may be based on assessments conducted by the States and/or a regional planning body.
(3) In a plan submitted no later than December 31, 2008, provide revisions to the plan submitted under paragraph (c) of this section, including provisions to establish reasonable progress goals and implement any additional measures necessary to demonstrate reasonable progress for the additional mandatory Federal Class I areas. These revisions must comply with the provisions of § 51.308(d)(1) through (4).
(4) The following provisions apply for Transport Region States establishing reasonable progress goals and adopting any additional measures for Class I areas other than the 16 Class I areas under paragraphs (g)(2) and (3) of this section.
(i) In developing long-term strategies pursuant to § 51.308(d)(3), the State may build upon the strategies implemented under paragraph (d) of this section, and take full credit for the visibility improvement achieved through these strategies.
(ii) The requirement under § 51.308(e) related to Best Available Retrofit Technology for regional haze is deemed to be satisfied for pollutants addressed by the milestones and backstop trading program if, in establishing the emission reductions milestones under paragraph (f) of this section, it is shown that greater reasonable progress will be achieved for these Class I areas than would be achieved through the application of source-specific BART emission limitations under § 51.308(e)(1).
(iii) The Transport Region State may consider whether any strategies necessary to achieve the reasonable progress goals required by paragraph (g)(3) of this section are incompatible with the strategies implemented under paragraph (d) of this section to the extent the State adequately demonstrates that the incompatibility is related to the costs of the compliance, the time necessary for compliance, the energy and no air quality environmental impacts of compliance, or the remaining useful life of any existing source subject to such requirements.
At 64 FR 35769, July 1, 1999, § 51.309 was added, effective Aug. 30, 1999.
Secs. 110, 301(a), 313, 319, Clean Air Act (42 U.S.C. 7410, 7601(a), 7613, 7619).
The requirements for reporting air quality data collected for purposes of the plan are located in subpart C of part 58 of this chapter.
On an annual (calendar year) basis beginning with calendar year 1979, the State agency shall report to the Administrator (through the appropriate Regional Office) information as specified in §§ 51.323 through 51.326. Reports must be submitted by July 1 of each year for data collected and actions which took place during the period January 1 to December 31 of the previous year.
(a) Point sources subject to the annual emissions reporting requirements of § 51.321 are defined as follows:
(1) For particulate matter, PM
(2) For carbon monoxide, any facility that actually emits a total of 1814 metric tons (2000 tons) per year or more.
(3) For lead or lead compounds measured as elemental lead, any facility that actually emits a total of 4.5 metric tons (5 tons) per year or more.
(b) Annual emissions reporting requirements apply only to emissions of each pollutant from any individual emission point within the facility that emits:
(1) For particulate matter, PM
(2) For carbon monoxide, 227 metric tons (250 tons) per year or more.
(3) For lead or lead compounds measured as elemental lead, 4.5 metric tons (5 tons) per year or more.
(a) The State shall submit in the annual report the following emissions data and information:
(1) Emissions of particulate matter (PM10), sulfur oxides, carbon monoxide, nitrogen oxides, VOC and lead or lead compounds measured as elemental lead as specified by the AIRS Facility Subsystem User's Guide AF2 “AFS Data Coding” (EPA-454/B-94-004) point source coding form,
(2) [Reserved]
(3) Emissions of PM 2.5 as will be specified in a future guideline.
(b) Such emissions data and information specified in paragraph (a) of this section must be submitted to the AIRS/AFS database via either online data entry or batch update system.
(c) The emissions data and information specified by paragraph (a) of this section must be submitted in the annual report for any point source for which one or more of the following conditions occurs:
(1) A source achieves compliance at any time within the reporting period with any regulation of an applicable plan,
(2) A new or modified source receives approval to construct during the reporting period or begins operating during the reporting period,
(3) A source ceases operations during the reporting period, or
(4) A source's emissions have changed more than 5% from the most recently submitted emissions data.
(d) If, as determined by the State and the Regional Administrator, the emissions from any point source have not changed more than 5% from the most recently submitted emissions data, the State shall update the year of record of the previously reported data and information specified by paragraph (a) of this section.
(a) For each point source, the State shall report any achievement made during the reporting period of any increment of progress of compliance schedules required by:
(1) The applicable plan, or
(2) Any enforcement order or other State action required to be submitted pursuant to § 51.327.
(b) For each point source, the State shall report any enforcement action taken during the reporting period and not submitted under § 51.327 which results in civil or criminal penalties.
The State shall identify and describe all substantive plan revisions during the reporting period of the applicable plan other than revisions to rules and regulations or compliance schedules submitted in accordance with § 51.6(d). Substantive revisions shall include but are not limited to changes in stack-test procedures for determining compliance with applicable regulations, modifications in the projected total manpower needs to carry out the approved plan, and all changes in responsibilities given to local agencies to carry out various portions of the plan.
(a) Any State enforcement order, including any State court order, must be submitted to the Administrator within 60 days of its issuance or adoption by the State.
(b) A State enforcement order or other State action must be submitted as a revision to the applicable implementation plan pursuant to § 51.104 and approved by the Administrator in order to be considered a revision to such plan.
(a) Upon request of the State made in accordance with this section, the Administrator may, whenever he determines necessary, extend, for a period not to exceed 18 months, the deadline for submitting that portion of a plan that implements a secondary standard.
(b) Any such request must show that attainment of the secondary standards will require emission reductions exceeding those which can be achieved through the application of reasonably available control technology.
(c) Any such request for extension of the deadline with respect to any State's portion of an interstate region must be submitted jointly with requests for such extensions from all other States within the region or must show that all such States have been notified of such request.
(d) Any such request must be submitted sufficiently early to permit development of a plan prior to the deadline in the event that such request is denied.
Inspection/maintenance (I/M) programs are required in both ozone and carbon monoxide (CO) nonattainment areas, depending upon population and nonattainment classification or design value.
(a)
(2) Apart from those areas described in paragraph (a)(1) of this section, any area classified as serious or worse ozone nonattainment, or as moderate or serious CO nonattainment with a design value greater than 12.7 ppm, and having a 1980 Bureau of Census-defined (Census-defined) urbanized area population of 200,000 or more, shall implement enhanced I/M in the 1990 Census-defined urbanized area.
(3) Any area classified, as of November 5, 1992, as marginal ozone nonattainment or moderate CO nonattainment with a design value of 12.7 ppm or less shall continue operating I/M programs that were part of an approved State Implementation Plan (SIP) as of November 15, 1990, and shall update those programs as necessary to meet the basic I/M program requirements of this subpart. Any such area required by the Clean Air Act, as in effect prior to November 15, 1990, as interpreted in EPA guidance, to have an I/M program shall also implement a basic I/M program. Serious, severe and extreme ozone areas and CO areas over 12.7 ppm shall also continue operating existing -I/M programs and shall upgrade such programs, as appropriate, pursuant to this subpart.
(4) Any area classified as moderate ozone nonattainment, and not required
(5) [Reserved]
(6) If the boundaries of a moderate ozone nonattainment area are changed pursuant to section 107(d)(4)(A)(i)-(ii) of the Clean Air Act, such that the area includes additional urbanized areas with a population of 200,000 or more, then a basic I/M program shall be implemented in these additional urbanized areas.
(7) If the boundaries of a serious or worse ozone nonattainment area or of a moderate or serious CO nonattainment area with a design value greater than 12.7 ppm are changed any time after enactment pursuant to section 107(d)(4)(A) such that the area includes additional urbanized areas, then an enhanced I/M program shall be implemented in the newly included 1990 Census-defined urbanized areas, if the 1980 Census-defined urban area population is 200,000 or more.
(8) If a marginal ozone nonattainment area, not required to implement enhanced I/M under paragraph (a)(1) of this section, is reclassified to moderate, a basic I/M program shall be implemented in the 1990 Census-defined urbanized area(s) with a population of 200,000 or more. If the area is reclassified to serious or worse, an enhanced I/M program shall be implemented in the 1990 Census-defined urbanized area, if the 1980 Census-defined urban area population is 200,000 or more.
(9) If a moderate ozone or CO nonattainment area is reclassified to serious or worse, an enhanced I/M program shall be implemented in the 1990 Census-defined urbanized area, if the 1980 Census-defined population is 200,000 or more.
(b)
(2) Outside of ozone transport regions, programs shall nominally cover at least the entire urbanized area, based on the 1990 census. Exclusion of some urban population is allowed as long as an equal number of non-urban residents of the MSA containing the subject urbanized area are included to compensate for the exclusion.
(3) Emission reduction benefits from expanding coverage beyond the minimum required urban area boundaries can be applied toward the reasonable further progress requirements or can be used for offsets, provided the covered vehicles are operated in the nonattainment area, but not toward the enhanced I/M performance standard requirement.
(4) In a multi-state urbanized area with a population of 200,000 or more that is required under paragraph (a) of this section to implement I/M, any State with a portion of the area having a 1990 Census-defined population of 50,000 or more shall implement an I/M program. The other coverage requirements in paragraph (b) of this section shall apply in multi-state areas as well.
(5) Notwithstanding the limitation in paragraph (b)(3) of this section, in an ozone transport region, States which opt for a program which meets the performance standard described in § 51.351(h) and claim in their SIP less emission reduction credit than the basic performance standard for one or more pollutants, may apply a geographic bubble covering areas in the State not otherwise subject to an I/M requirement to achieve emission reductions from other measures equal to or greater than what would have been achieved if the low enhanced performance standard were met in the subject I/M areas. Emissions reductions from non-I/M measures shall not be counted towards the OTR low enhanced performance standard.
(c)
(d)
(a) Enhanced I/M programs shall be designed and implemented to meet or exceed a minimum performance standard, which is expressed as emission levels in area-wide average grams per mile (gpm), achieved from highway mobile sources as a result of the program. The emission levels achieved by the State's program design shall be calculated using the most current version, at the time of submittal, of the EPA mobile source emission factor model or an alternative model approved by the Administrator, and shall meet the minimum performance standard both in operation and for SIP approval. Areas shall meet the performance standard for the pollutants which cause them to be subject to enhanced I/M requirements. In the case of ozone nonattainment areas subject to enhanced I/M and subject areas in the Ozone Transport Region, the performance standard must be met for both oxides of nitrogen (NO
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(ii) Emission standards for 1986 through 1993 light duty trucks less than 6000 pounds gross vehicle weight rating (GVWR), and 1994 and 1995 trucks not meeting Tier 1 emission standards, of 1.2 gpm HC, 20 gpm CO, and 3.5 gpm NO
(iii) Emission standards for 1986 through 1993 light duty trucks greater than 6000 pounds GVWR, and 1994 and 1995 trucks not meeting Tier 1 emission standards, of 1.2 gpm HC, 20 gpm CO, and 3.5 gpm NO
(iv) Emission standards for 1994 and later light duty vehicles meeting Tier 1 emission standards of 0.70 gpm HC, 15 gpm CO, and 1.4 gpm NO
(v) Emission standards for 1994 and later light duty trucks under 6000 pounds GVWR and meeting Tier 1 emission standards of 0.70 gpm HC, 15 gpm CO and 2.0 gpm NO
(vi) Emission standards for 1994 and later light duty trucks greater than 6000 pounds GVWR and meeting Tier 1 emission standards of 0.80 gpm HC, 15 gpm CO and 2.0 gpm NO
(vii) Emission standards for 1981-1985 model year vehicles of 1.2% CO, and 220 ppm HC for the idle, two-speed tests and loaded steady-state tests (as described in appendix B of this subpart S); and
(viii) Maximum exhaust dilution measured as no less than 6% CO plus
(8)
(9)
(10)
(11)
(12)
(13)
(b)
(c)
(d)
(e) [Reserved]
(f)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(ii) Emission standards for 1986 through 1993 light duty trucks less than 6000 pounds gross vehicle weight rating (GVWR), and 1994 and 1995
(iii) Emission standards for 1986 through 1993 light duty trucks greater than 6000 pounds GVWR, and 1994 and 1995 trucks not meeting the Tier 1 emission standards, of 1.2 gpm HC, 20 gpm CO, and 3.5 gpm NO
(iv) Emission standards for 1994 and later light duty vehicles meeting Tier 1 emission standards of 0.70 gpm HC, 15 gpm CO, and 1.4 gpm NO
(v) Emission standards for 1994 and later light duty trucks under 6000 pounds GVWR and meeting Tier 1 emission standards of 0.70 gpm HC, 15 gpm CO, and 2.0 gpm NO
(vi) Emission standards for 1994 and later light duty trucks greater than 6000 pounds GVWR and meeting Tier 1 emission standards of 0.80 gpm HC, 15 gpm CO and 2.5 gpm NO
(vii) Emission standards for 1981-1985 model year vehicles of 1.2% CO, and 220 gpm HC for the idle, two-speed tests and loaded steady-state tests (as described in appendix B of this subpart S); and
(viii) Maximum exhaust dilution measured as no less than 6% CO plus carbon dioxide (CO
(viii) Maximum exhaust dilution measured as no less than 6% CO plus carbon dioxide (CO
(8)
(ii) Visual inspection of the positive crankcase ventilation valve on 1968 through 1971 model years, inclusive, and of the exhaust gas recirculation valve on 1972 through 1983 model year vehicles, inclusive.
(9)
(10)
(11)
(12)
(13)
(g)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12) Compliance rate. A 96% compliance rate.
(13) Evaluation date. Enhanced I/M program areas subject to the provisions of this paragraph shall be shown to obtain the same or lower emission levels as the model program described in this paragraph by 2000 for ozone nonattainment areas and 2001 for CO nonattainment areas, and for severe and extreme ozone nonattainment areas, on each applicable milestone and attainment deadline, thereafter. Milestones for NO
(h)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(a) Basic I/M programs shall be designed and implemented to meet or exceed a minimum performance standard, which is expressed as emission levels achieved from highway mobile sources as a result of the program. The performance standard shall be established using the following model I/M program inputs and local characteristics, such as vehicle mix and local fuel controls. Similarly, the emission reduction benefits of the State's program design shall be estimated using the most current version of the EPA mobile source emission model, and shall meet the minimum performance standard both in operation and for SIP approval.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(b)
(c)
(d)
Enhanced I/M programs shall be operated in a centralized test-only format, unless the State can demonstrate that a decentralized program is equally effective in achieving the enhanced I/M performance standard. Basic I/M programs can be centralized, decentralized, or a hybrid at the State's discretion, but shall be demonstrated to achieve the same emission reduction as the program described in § 51.352 of this subpart.
(a)
(b)
(i) Surveys that assess the effectiveness of repairs performed on vehicles that failed the tailpipe emission test and evaporative system tests;
(ii) In programs including tampering checks, measurement of actual tampering rates, their change over time, and the change attributable to finding and fixing such tampering as opposed to deterrence effects; and
(iii) The results of undercover surveys of inspector effectiveness as it relates to identifying vehicles that need repair.
(2) In the case of hybrid systems, which may be implemented in basic I/M areas, including both test-only and test-and-repair facilities, full credit shall apply to the portion of the fleet initially tested and subsequently retested at a test-only facility meeting the requirements of paragraph (a) of this section, and to the portion of the fleet initially tested and failed at a test-and-repair facility but subsequently passing a comprehensive retest at a test-only facility meeting those same requirements. The credit loss assumptions described in paragraph (b)(1) of this section shall apply to the portion of the fleet initially passed at a test-and-repair facility, and to the portion initially failed at a test-only facility and retested at a test-and-repair facility.
(3) Areas operating test-and-repair networks or hybrid networks may, in the future, claim greater effectiveness than described in paragraph (b)(1) of this section, if a demonstration of greater effectiveness is made to the satisfaction of the Administrator using the program evaluation protocol described in paragraph (c) of this section.
(c)
(1) The State shall report the results of the program evaluation on a biennial basis, starting two years after the initial start date of mandatory testing as required in § 51.373 of this subpart.
(2) The evaluation shall be considered in establishing actual emission reductions achieved from I/M for the purposes of satisfying the requirements of sections 182(g)(1) and 182(g)(2) of the Clean Air Act, relating to reductions in emissions and compliance demonstration.
(3) The evaluation program shall consist, at a minimum, of those items described in paragraph (b)(1) of this section and program evaluation data using a sound evaluation methodology, as approved by EPA, and evaporative system checks, specified in § 51.357(a) (9) and (10) of this subpart, for model years subject to those evaporative system test procedures. The test data shall be obtained from a representative, random sample, taken at the time of initial inspection (before repair) on a minimum of 0.1 percent of the vehicles subject to inspection in a given year. Such vehicles shall receive a State administered or monitored test, as specified in this paragraph (c)(3), prior to the performance of I/M-triggered repairs during the inspection cycle under consideration.
(4) The program evaluation test data shall be submitted to EPA and shall be capable of providing accurate information about the overall effectiveness of an I/M program, such evaluation to begin no later than November 30, 1998.
(5) Areas that qualify for and choose to implement an OTR low enhanced I/M program, as established in § 51.351(h), and that claim in their SIP less emission reduction credit than the basic performance standard for one or more pollutants, are exempt from the requirements of paragraphs (c)(1) through (c)(4) of this section. The reports required under § 51.366 of this part
(d)
(2) The SIP shall include a description of the evaluation schedule and protocol, the sampling methodology, the data collection and analysis system, the resources and personnel for evaluation, and related details of the evaluation program, and the legal authority enabling the evaluation program.
(a)
(b)
(c)
(d)
(1) The SIP shall include a detailed budget plan which describes the source of funds for personnel, program administration, program enforcement, purchase of necessary equipment (such as vehicles for undercover audits), and any other requirements discussed throughout, for the period prior to the next biennial self-evaluation required in § 51.366 of this subpart.
(2) The SIP shall include a description of personnel resources. The plan shall include the number of personnel dedicated to overt and covert auditing, data analysis, program administration, enforcement, and other necessary functions and the training attendant to each function.
(a) The performance standards for I/M programs assume an annual test frequency; other schedules may be approved if the required emission targets are achieved. The SIP shall describe the test schedule in detail, including the test year selection scheme if testing is other than annual. The SIP shall include the legal authority necessary to implement and enforce the test frequency requirement and explain how the test frequency will be integrated with the enforcement process.
(b) In enhanced I/M programs, test systems shall be designed in such a way as to provide convenient service to motorists required to get their vehicles
The performance standard for enhanced I/M programs assumes coverage of all 1968 and later model year light duty vehicles and light duty trucks up to 8,500 pounds GVWR, and includes vehicles operating on all fuel types. The standard for basic I/M programs does not include light duty trucks. Other levels of coverage may be approved if the necessary emission reductions are achieved. Vehicles registered or required to be registered within the I/M program area boundaries and fleets primarily operated within the I/M program area boundaries and belonging to the covered model years and vehicle classes comprise the subject vehicles.
(a)
(2) All subject fleet vehicles shall be inspected. Fleets may be officially inspected outside of the normal I/M program test facilities, if such alternatives are approved by the program administration, but shall be subject to the same test requirements using the same quality control standards as non-fleet vehicles. If all vehicles in a particular fleet are tested during one part of the cycle, then the quality control requirements shall be met during the time of testing only. Any vehicle available for rent in the I/M area or for use in the I/M area shall be subject. Fleet vehicles not being tested in normal I/M test facilities in enhanced I/M programs, however, shall be inspected in independent, test-only facilities, according to the requirements of § 51.353(a) of this subpart.
(3) Subject vehicles which are registered in the program area but are primarily operated in another I/M area shall be tested, either in the area of primary operation, or in the area of registration. Alternate schedules may be established to permit convenient testing of these vehicles (e.g., vehicles belonging to students away at college should be rescheduled for testing during a visit home). I/M programs shall make provisions for providing official testing to vehicles registered elsewhere.
(4) Vehicles which are operated on Federal installations located within an I/M program area shall be tested, regardless of whether the vehicles are registered in the State or local I/M area. This requirement applies to all employee-owned or leased vehicles (including vehicles owned, leased, or operated by civilian and military personnel on Federal installations) as well as agency-owned or operated vehicles, except tactical military vehicles, operated on the installation. This requirement shall not apply to visiting agency, employee, or military personnel vehicles as long as such visits do not exceed 60 calendar days per year. In areas without test fees collected in the lane, arrangements shall be made by the installation with the I/M program for reimbursement of the costs of tests provided for agency vehicles, at the discretion of the I/M agency. The installation shall provide documentation of proof of compliance to the I/M agency. The documentation shall include a list of subject vehicles and shall be updated periodically, as determined by the I/M program administrator, but no less frequently than each inspection cycle. The installation shall use one of the following methods to establish proof of compliance:
(i) Presentation of a valid certificate of compliance from the local I/M program, from any other I/M program at least as stringent as the local program, or from any program deemed acceptable by the I/M program administrator.
(ii) Presentation of proof of vehicle registration within the geographic area covered by the I/M program, except for any program whose enforcement is not through registration denial.
(iii) Another method approved by the State or local I/M program administrator.
(5) Special exemptions may be permitted for certain subject vehicles provided a demonstration is made that the performance standard will be met.
(b)
(2) The SIP shall include a description of any special exemptions which will be granted by the program, and an estimate of the percentage and number of subject vehicles which will be impacted. Such exemptions shall be accounted for in the emission reduction analysis.
(3) The SIP shall include the legal authority or rule necessary to implement and enforce the vehicle coverage requirement.
Written test procedures and pass/fail standards shall be established and followed for each model year and vehicle type included in the program.
(a)
(1) Initial tests (i.e., those occurring for the first time in a test cycle) shall be performed without repair or adjustment at the inspection facility, prior to the test, except as provided in paragraph (a)(10)(i) of this section.
(2) The vehicle owner or driver shall have access to the test area such that observation of the entire official inspection process on the vehicle is permitted. Such access may be limited but shall in no way prevent full observation.
(3) An official test, once initiated, shall be performed in its entirety regardless of intermediate outcomes except in the case of invalid test condition, unsafe conditions, or fast pass/fail algorithms.
(4) Tests involving measurement shall be performed with program-approved equipment that has been calibrated accordingly to the quality procedures contained in appendix A to this subpart.
(5) Vehicles shall be rejected from testing if the exhaust system is missing or leaking, or if the vehicle is in an unsafe condition for testing.
(6) Vehicles shall be retested after repair for any portion of the inspection that is failed on the previous test to determine if repairs were effective. To the extent that repair to correct a previous failure could lead to failure of another portion of the test, that portion shall also be retested. Evaporative system repairs shall trigger an exhaust emissions retest.
(7)
(8)
(9)
(10)
(i) Test equipment shall be connected to the fuel tank canister hose at the canister end. The gas cap shall be checked to ensure that it is properly, but not excessively tightened, and shall be tightened if necessary.
(ii) The system shall be pressurized to 14
(iii) Close off the pressure source, seal the evaporative system and monitor pressure decay for up to two minutes.
(iv) Loosen the gas cap after a maximum of two minutes and monitor for a sudden pressure drop, indicating that the fuel tank was pressurized.
(v) The inspector shall be responsible for ensuring that all items that are disconnected in the conduct of the test procedure are properly re-connected at the conclusion of the test procedure.
(vi) Alternative procedures may be used if they are shown to be equivalent or better to the satisfaction of the Administrator. Except in the case of government-run test facilities claiming sovereign immunity, any damage done to the evaporative emission control system during this test shall be repaired at the expense of the inspection facility.
(11)
(12)
(13)
(i) Such procedures are in accordance with good engineering practice, including errors of commission (at cutpoints corresponding to equivalent emission reductions) no higher than the tests they would replace;
(ii) Such procedures show a correlation with the Federal Test Procedure (with respect to their ability to detect high emitting vehicles and ensure their effective repair) equal to or better than the tests they would replace; and
(iii) Such procedures would produce equivalent emission reductions in combination with other program elements.
(b)
(i)
(ii)
(2)
(ii) Vehicles shall fail visual inspections of subject emission control devices if such devices are found to be incorrect for the certified vehicle configuration under inspection. Aftermarket parts, as well as original
(3)
(ii)
(4)
(c)
(d)
(1) Vehicles with engines other than the engine originally installed by the manufacturer or an identical replacement of such engine shall be subject to the test procedures and standards for the chassis type and model year including visual equipment inspections for all parts that are part of the original or now-applicable certified configuration and part of the normal inspection. States may choose to require vehicles with such engines to be subject to the test procedures and standards for the engine model year if it is newer than the chassis model year.
(2) Vehicles that have been switched from an engine of one fuel type to another fuel type that is subject to the program (e.g., from a diesel engine to a gasoline engine) shall be subject to the test procedures and standards for the current fuel type, and to the requirements of paragraph (d)(1) of this section.
(3) Vehicles that are switched to a fuel type for which there is no certified configuration shall be tested according to the most stringent emission standards established for that vehicle type and model year. Emission control device requirements may be waived if the program determines that the alternatively fueled vehicle configuration would meet the new vehicle standards for that model year without such devices.
(4) Mixing vehicle classes (e.g., light-duty with heavy-duty) and certification types (e.g., California with Federal) within a single vehicle configuration shall be considered tampering.
(e)
Computerized test systems are required for performing any measurement on subject vehicles.
(a)
(1) Emission test equipment shall be capable of testing all subject vehicles and shall be updated from time to time to accommodate new technology vehicles as well as changes to the program.
(2) At a minimum, emission test equipment:
(i) Shall be automated to the highest degree commercially available to minimize the potential for intentional fraud and/or human error;
(ii) Shall be secure from tampering and/or abuse;
(iii) Shall be based upon written specifications; and
(iv) Shall be capable of simultaneously sampling dual exhaust vehicles.
(3) The vehicle owner or driver shall be provided with a computer-generated record of test results, including all of the items listed in 40 CFR part 85, subpart W as being required on the test record. The test report shall include:
(i) A vehicle description, including license plate number, vehicle identification number, and odometer reading;
(ii) The date and time of test;
(iii) The name or identification number of the individual(s) performing the tests and the location of the test station and lane;
(iv) The type of tests performed, including emission tests, visual checks for the presence of emission control components, and functional, evaporative system checks;
(v) The applicable test standards;
(vi) The test results, including exhaust concentrations and pass/fail results for each mode measured, pass/fail results for evaporative system checks, and which emission control devices inspected were passed, failed, or not applicable;
(vii) A statement indicating the availability of warranty coverage as required in section 207 of the Clean Air Act;
(viii) Certification that tests were performed in accordance with the regulations and, in the case of decentralized programs, the signature of the individual who performed the test; and
(ix) For vehicles that fail the tailpipe emission test, information on the possible causes of the specific pattern of high emission levels found during the test.
(b)
(1) The test system shall automatically:
(i) Make a pass/fail decision for all measurements;
(ii) Record test data to an electronic medium;
(iii) Conduct regular self-testing of recording accuracy;
(iv) Perform electrical calibration and system integrity checks before each test, as applicable; and
(v) Initiate system lockouts for:
(A) Tampering with security aspects of the test system;
(B) Failing to conduct or pass periodic calibration or leak checks;
(C) Failing to conduct or pass the constant volume sampler flow rate check (if applicable);
(D) Failing to conduct or pass any of the dynamometer checks, including coast-down, roll speed and roll distance, power absorption capability, and inertia weight selection checks (if applicable);
(E) Failing to conduct or pass the pressure monitoring device check (if applicable);
(F) Failing to conduct or pass the purge flow metering system check (if applicable); and
(G) A full data recording medium or one that does not pass a cyclical redundancy check.
(2) Test systems in enhanced I/M programs shall include a real-time data link to a host computer that prevents unauthorized multiple initial tests on the same vehicle in a test cycle and to insure test record accuracy.
(3) The test system shall insure accurate data collection by limiting, cross-checking, and/or confirming manual data entry.
(4)
(c)
Quality control measures shall insure that emission measurement equipment is calibrated and maintained properly, and that inspection, calibration records, and control charts are accurately created, recorded and maintained.
(a)
(2) Preventive maintenance on all inspection equipment necessary to insure accurate and repeatable operation shall be performed on a periodic basis.
(3) Computerized analyzers shall automatically record quality control check information, lockouts, attempted tampering, and any other recordable circumstances which should be monitored to insure quality control (e.g., service calls).
(b)
(2) For analyzers that use ambient air as zero air, provision shall be made to draw the air from outside the inspection bay or lane in which the analyzer is situated.
(3) The analyzer housing shall be constructed to protect the analyzer bench and electrical components from ambient temperature and humidity fluctuations that exceed the range of the analyzer's design specifications.
(4) Analyzers shall automatically purge the analytical system after each test.
(c)
(d)
(e)
(1) Compliance documents shall be counterfeit resistant. Such measures as the use of special fonts, water marks, ultra-violet inks, encoded magnetic strips, unique bar-coded identifiers, and difficult to acquire materials may be used to accomplish this requirement.
(2) All inspection certificates, waiver certificates, and stickers shall be
(3) Measures shall be taken to ensure that compliance documents cannot be stolen or removed without being damaged.
(f)
The program may allow the issuance of a waiver, which is a form of compliance with the program requirements that allows a motorist to comply without meeting the applicable test standards, as long as the prescribed criteria described below are met.
(a)
(1) Waivers shall be issued only after a vehicle has failed a retest performed after all qualifying repairs have been completed. Qualifying repairs include repairs of the emission control components, listed in paragraph (a)(5) of this section, performed within 60 days of the test date.
(2) Any available warranty coverage shall be used to obtain needed repairs before expenditures can be counted towards the cost limits in paragraphs (a)(5) and (a)(6) of this section. The operator of a vehicle within the statutory age and mileage coverage under section 207(b) of the Clean Air Act shall present a written denial of warranty coverage from the manufacturer or authorized dealer for this provision to be waived for approved tests applicable to the vehicle.
(3) Waivers shall not be issued to vehicles for tampering-related repairs. The cost of tampering-related repairs shall not be applicable to the minimum expenditure in paragraphs (a)(5) and (a)(6) of this section. States may issue exemptions for tampering-related repairs if it can be verified that the part in question or one similar to it is no longer available for sale.
(4) Repairs shall be appropriate to the cause of the test failure, and a visual check shall be made to determine if repairs were actually made if, given the nature of the repair, it can be visually confirmed. Receipts shall be submitted for review to further verify that qualifying repairs were performed.
(5) General repairs shall be performed by a recognized repair technician (i.e., one professionally engaged in vehicle repair, employed by a going concern whose purpose is vehicle repair, or possessing nationally recognized certification for emission-related diagnosis and repair) in order to qualify for a waiver. I/M programs may allow the cost of parts (not labor) utilized by non-technicians (e.g., owners) to apply toward the waiver limit. The waiver would apply to the cost of parts for the repair or replacement of the following list of emission control components: oxygen sensor, catalytic converter, thermal reactor, EGR valve, fuel filler cap, evaporative canister, PCV valve, air pump, distributor, ignition wires, coil, and spark plugs. The cost of any hoses, gaskets, belts, clamps, brackets or other accessories directly associated with these components may also be applied to the waiver limit.
(6) In basic programs, a minimum of $75 for pre-81 vehicles and $200 for 1981 and newer vehicles shall be spent in order to qualify for a waiver. These model year cutoffs and the associated dollar limits shall be in full effect no later than January 1, 1998. Prior to January 1, 1998, States may adopt any minimum expenditure commensurate with the waiver rate committed to for the purposes of modeling compliance with the basic I/M performance standard.
(7) Beginning on January 1, 1998, enhanced I/M programs shall require the motorist to make an expenditure of at least $450 in repairs to qualify for a waiver. The I/M program shall provide that the $450 minimum expenditure shall be adjusted in January of each year by the percentage, if any, by which the Consumer Price Index for the preceding calendar year differs from the Consumer Price Index of 1989. Prior to January 1, 1998, States may
(i) The Consumer Price Index for any calendar year is the average of the Consumer Price Index for all-urban consumers published by the Department of Labor, as of the close of the 12-month period ending on August 31 of each calendar year. A copy of the current Consumer Price Index may be obtained from the Emission Planning and Strategies Division, U.S. Environmental Protection Agency, 2565 Plymouth Road, Ann Arbor, Michigan 48105.
(ii) The revision of the Consumer Price Index which is most consistent with the Consumer Price Index for calendar year 1989 shall be used.
(8) States may establish lower minimum expenditures if a program is established to scrap vehicles that do not meet standards after the lower expe nditure is made.
(9) A time extension, not to exceed the period of the inspection frequency, may be granted to obtain needed repairs on a vehicle in the case of economic hardship when waiver requirements have not been met. After having received a time extension, a vehicle must fully pass the applicable test standards before becoming eligible for another time extension. The extension for a vehicle shall be tracked and reported by the program.
(b)
(c)
(2) The program shall include methods of informing vehicle owners or lessors of potential warranty coverage, and ways to obtain warranty repairs.
(3) The program shall insure that repair receipts are authentic and cannot be revised or reused.
(4) The program shall insure that waivers are only valid for one test cycle.
(5) The program shall track, manage, and account for time extensions or exemptions so that owners or lessors cannot receive or retain a waiver improperly.
(d)
(2) The State shall take corrective action if the waiver rate exceeds that committed to in the SIP or revise the SIP and the emission reductions claimed.
(3) The SIP shall describe the waiver criteria and procedures, including cost limits, quality assurance methods and measures, and administration.
(4) The SIP shall include the necessary legal authority, ordinance, or rules to issue waivers, set and adjust cost limits as required in paragraph (a)(5) of this section, and carry out any other functions necessary to administer the waiver system, including enforcement of the waiver provisions.
Compliance shall be ensured through the denial of motor vehicle registration in enhanced I/M programs unless an exception for use of an existing alternative is approved. An enhanced I/M area may use an existing alternative if it demonstrates that the alternative
(a)
(1) Provide an external, readily visible means of determining vehicle compliance with the registration requirement to facilitate enforcement of the program;
(2) Adopt a schedule of testing (either annual or biennial) that clearly determines when a vehicle shall comply prior to registration;
(3) Design a testing certification mechanism (either paper-based or electronic) that shall be used for registration purposes and clearly indicates whether the certification is valid for purposes of registration, including:
(i) Expiration date of the certificate;
(ii) Unambiguous vehicle identification information; and
(iii) Whether the vehicle passed or received a waiver;
(4) Routinely issue citations to motorists with expired or missing license plates, with either no registration or an expired registration, and with no license plate decals or expired decals, and provide for enforcement officials other than police to issue citations (e.g., parking meter attendants) to parked vehicles in noncompliance;
(5) Structure the penalty system to deter non-compliance with the registration requirement through the use of mandatory minimum fines (meaning civil, monetary penalties, in this subpart) constituting a meaningful deterrent and through a requirement that compliance be demonstrated before a case can be closed;
(6) Ensure that evidence of testing is available and checked for validity at the time of a new registration of a used vehicle or registration renewal;
(7) Prevent owners or lessors from avoiding testing through manipulation of the title or registration system; title transfers may re-start the clock on the inspection cycle only if proof of current compliance is required at title transfer;
(8) Prevent the fraudulent initial classification or reclassification of a vehicle from subject to non-subject or exempt by requiring proof of address changes prior to registration record modification, and documentation from the testing program (or delegate) certifying based on a physical inspection that the vehicle is exempt;
(9) Limit and track the use of time extensions of the registration requirement to prevent repeated extensions;
(10) Provide for meaningful penalties for cases of registration fraud;
(11) Limit and track exemptions to prevent abuse of the exemption policy for vehicles claimed to be out-of-state; and
(12) Encourage enforcement of vehicle registration transfer requirements when vehicle owners move into the I/M area by coordinating with local and State enforcement agencies and structuring other activities (e.g., drivers license issuance) to effect registration transfers.
(b)
(i) For enhanced I/M programs, the area in question shall have had an operating I/M program using the alternative mechanism prior to enactment of the Clean Air Act Amendments of 1990. While modifications to improve compliance may be made to the program that was in effect at the time of enactment, the expected change in effectiveness cannot be considered in determining acceptability;
(ii) The State shall assess the alternative program's effectiveness, as well as the current effectiveness of the registration system, including the following:
(A) Determine the number and percentage of vehicles subject to the I/M program that were in compliance with the program over the course of at least one test cycle; and
(B) Determine the number and fraction of the same group of vehicles as in paragraph (b)(1)(ii)(A) of this section that were in compliance with the registration requirement over the same period. Late registration shall not be considered non-compliance for the purposes of this determination. The precise definition of late registration versus a non-complying vehicle shall be explained and justified in the SIP;
(iii) An alternative mechanism shall be considered more effective if the fraction of vehicles complying with the existing program, as determined according to the requirements of this section, is greater than the fraction of vehicles complying with the registration requirement. An alternative mechanism is as effective if the fraction complying with the program is at least equal to the fraction complying with the registration requirement.
(2)
(i) An assessment of the current extent of the following forms of non-compliance and demonstration that mechanisms exist to keep such non-compliance within acceptable limits:
(A) Use of stolen, counterfeit, or fraudulently obtained stickers;
(B) In States with safety inspections, the use of “Safety Inspection Only” stickers on vehicles that should be subject to the I/M requirement as well; and
(C) Operation of vehicles with expired stickers, including a stratification of non-compliance by length of noncompliance and model year.
(ii) The program as currently implemented or as proposed to be improved shall also:
(A) Require an easily observed external identifier such as the county name on the license plate, an obviously unique license plate tab, or other means that shows whether or not a vehicle is subject to the I/M requirement;
(B) Require an easily observed external identifier, such as a windshield sticker or license plate tab that shows whether a subject vehicle is in compliance with the inspection requirement;
(C) Impose monetary fines at least as great as the estimated cost of compliance with I/M requirements (e.g., test fee plus minimum waiver expenditure) for the absence of such identifiers;
(D) Require that such identifiers be of a quality that makes them difficult to counterfeit, difficult to remove without destroying once installed, and durable enough to last until the next inspection without fading, peeling, or other deterioration;
(E) Perform surveys in a variety of locations and at different times for the presence of the required identifiers such that at least 10% of the vehicles or 10,000 vehicles (whichever is less) in the subject vehicle population are sampled each year;
(F) Track missing identifiers for all inspections performed at each station, with stations being held accountable for all such identifiers they are issued; and
(G) Assess and collect significant fines for each identifier that is unaccounted for by a station.
(3)
(i) Require an expeditious system that results in at least 90% of the subject vehicles in compliance within 4 months of the compliance deadline;
(ii) Require that subject vehicles be given compliance deadlines based on the regularly scheduled test date, not the date of previous compliance;
(iii) Require that motorists pay monetary fines at least as great as the estimated cost of compliance with I/M requirements (e.g., test fee plus minimum waiver expenditure) for the continued operation of a noncomplying vehicle beyond 4 months of the deadline;
(iv) Require that continued non-compliance will eventually result in preventing operation of the non-complying vehicle (no later than the date of the next test cycle) through, at a minimum, suspension of vehicle registration and subsequent denial of reregistration;
(v) Demonstrate that the computer system currently in use is adequate to store and manipulate the I/M vehicle database, generate computerized notices, and provide regular backup to said system while maintaining auxiliary storage devices to insure ongoing operation of the system and prevent data losses;
(vi) Track each vehicle through the steps taken to ensure compliance, including:
(A) The compliance deadline;
(B) The date of initial notification;
(C) The dates warning letters are sent to non-complying vehicle owners;
(D) The dates notices of violation or other penalty notices are sent; and
(E) The dates and outcomes of other steps in the process, including the final compliance date;
(vii) Compile and report monthly summaries including statistics on the percentage of vehicles at each stage in the enforcement process; and
(viii) Track the number and percentage of vehicles initially identified as requiring testing but which are never tested as a result of being junked, sold to a motorist in a non-I/M program area, or for some other reason.
(c)
(i) A description of the existing compliance mechanism if it is to be used in the future and the demonstration that it is as effective or more effective than registration-denial enforcement;
(ii) An identification of the agencies responsible for performing each of the applicable activities in this section;
(iii) A description of and accounting for all classes of exempt vehicles; and
(iv) A description of the plan for testing fleet vehicles, rental car fleets, leased vehicles, and any other subject vehicles, e.g., those operated in (but not necessarily registered in) the program area.
(2) The SIP shall include a determination of the current compliance rate based on a study of the system that includes an estimate of compliance losses due to loopholes, counterfeiting, and unregistered vehicles. Estimates of the effect of closing such loopholes and otherwise improving the enforcement mechanism shall be supported with detailed analyses.
(3) The SIP shall include the legal authority to implement and enforce the program.
(4) The SIP shall include a commitment to an enforcement level to be used for modeling purposes and to be maintained, at a minimum, in practice.
The enforcement program shall be audited regularly and shall follow effective program management practices, including adjustments to improve operation when necessary.
(a)
(1) Verification of exempt vehicle status by inspecting and confirming such vehicles by the program or its delegate;
(2) Facilitation of accurate critical test data and vehicle identifier collection through the use of automatic data capture systems such as bar-code scanners or optical character readers, or through redundant data entry;
(3) Maintenance of an audit trail to allow for the assessment of enforcement effectiveness;
(4) Establishment of written procedures for personnel directly engaged in I/M enforcement activities;
(5) Establishment of written procedures for personnel engaged in -I/M document handling and processing, such as registration clerks or personnel involved in sticker dispensing and waiver processing, as well as written procedures for the auditing of their performance;
(6) Follow-up validity checks on out-of-area or exemption-triggering registration changes;
(7) Analysis of registration-change applications to target potential violators;
(8) A determination of enforcement program effectiveness through periodic audits of test records and program compliance documentation;
(9) Enforcement procedures for disciplining, retraining, or removing enforcement personnel who deviate from established requirements, or in the case of non-government entities that process registrations, for defranchising, revoking or otherwise discontinuing the activity of the entity issuing registrations; and
(10) The prevention of fraudulent procurement or use of inspection documents by controlling and tracking document distribution and handling, and making stations financially liable for missing or unaccounted for documents by assessing monetary fines reflecting the “street value” of these documents (i.e., the test fee plus the minimum waiver expenditure).
(b)
(1) Determine the subject vehicle population;
(2) Permit EPA audits of the enforcement process;
(3) Assure the accuracy of registration and other program document files;
(4) Maintain and ensure the accuracy of the testing database through periodic internal and/or third-party review; through automated or redundant data entry; and, through automated analysis for valid alpha-numeric sequences of the vehicle identification number (VIN), certificate number, or license plate number;
(5) Compare the testing database to the registration database to determine program effectiveness, establish compliance rates, and to trigger potential enforcement action against non-complying motorists; and
(6) Sample the fleet as a determination of compliance through parking lot surveys, road-side pull-overs, or other in-use vehicle measurements.
(c)
An ongoing quality assurance program shall be implemented to discover, correct and prevent fraud, waste, and abuse and to determine whether procedures are being followed, are adequate, whether equipment is measuring accurately, and whether other problems might exist which would impede program performance. The quality assurance and quality control procedures shall be periodically evaluated to assess their effectiveness and relevance in achieving program goals.
(a)
(1) Performance audits based upon written procedures and results shall be reported using either electronic or written forms to be retained in the inspector and station history files, with sufficient detail to support either an administrative or civil hearing;
(2) Performance audits in addition to regularly programmed audits for stations employing inspectors suspected
(3) Overt performance audits shall be performed at least twice per year for each lane or test bay and shall include:
(i) A check for the observance of appropriate document security;
(ii) A check to see that required record keeping practices are being followed;
(iii) A check for licenses or certificates and other required display information; and
(iv) Observation and written evaluation of each inspector's ability to properly perform an inspection;
(4) Covert performance audits shall include:
(i) Remote visual observation of inspector performance, which may include the use of aids such as binoculars or video cameras, at least once per year per inspector in high-volume stations (i.e., those performing more than 4000 tests per year);
(ii) Site visits at least once per year per number of inspectors using covert vehicles set to fail (this requirement sets a minimum level of activity, not a requirement that each inspector be involved in a covert audit);
(iii) For stations that conduct both testing and repairs, at least one covert vehicle visit per station per year including the purchase of repairs and subsequent retesting if the vehicle is initially failed for tailpipe emissions (this activity may be accomplished in conjunction with paragraph (a)(4)(ii) of this section but must involve each station at least once per year);
(iv) Documentation of the audit, including vehicle condition and preparation, sufficient for building a legal case and establishing a performance record;
(v) Covert vehicles covering the range of vehicle technology groups (e.g., carbureted and fuel-injected vehicles) included in the program, including a full range of introduced malfunctions covering the emission test, the evaporative system tests, and emission control component checks (as applicable);
(vi) Sufficient numbers of covert vehicles and auditors to allow for frequent rotation of both to prevent detection by station personnel; and
(vii) Access to on-line inspection databases by State personnel to permit the creation and maintenance of covert vehicle records.
(b)
(1) Software-based, computerized analysis to identify statistical inconsistencies, unusual patterns, and other discrepancies;
(2) Visits to inspection stations to review records not already covered in the electronic analysis (if any); and
(3) Comprehensive accounting for all official forms that can be used to demonstrate compliance with the program.
(c)
(1) A gas audit using gases of known concentrations at least as accurate as those required for regular equipment quality control and comparing these concentrations to actual readings;
(2) A check for tampering, worn instrumentation, blocked filters, and other conditions that would impede accurate sampling;
(3) A check for critical flow in critical flow CVS units;
(4) A check of the Constant Volume Sampler flow calibration;
(5) A check for the optimization of the Flame Ionization Detection fuel-air ratio using methane;
(6) A leak check;
(7) A check to determine that station gas bottles used for calibration purposes are properly labelled and within the relevant tolerances;
(8) Functional dynamometer checks addressing coast-down, roll speed and roll distance, inertia weight selection, and power absorption;
(9) A check of the system's ability to accurately detect background pollutant concentrations;
(10) A check of the pressure monitoring devices used to perform the evaporative canister pressure test; and
(11) A check of the purge flow metering system.
(d)
(i) The use of analyzers;
(ii) Program rules and regulations;
(iii) The basics of air pollution control;
(iv) Basic principles of motor vehicle engine repair, related to emission performance;
(v) Emission control systems;
(vi) Evidence gathering;
(vii) State administrative procedures laws;
(viii) Quality assurance practices; and
(ix) Covert audit procedures.
(2) Auditors shall themselves be audited at least once annually.
(3) The training and knowledge requirements in paragraph (d)(1) of this section may be waived for temporary auditors engaged solely for the purpose of conducting covert vehicle runs.
(e)
Enforcement against licensed stations or contractors, and inspectors shall include swift, sure, effective, and consistent penalties for violation of program requirements.
(a)
(1) The schedule shall categorize and list violations and the minimum penalties to be imposed for first, second, and subsequent violations and for multiple violation of different requirements. In the case of contracted systems, the State may use compensation retainage in lieu of penalties.
(2) Substantial penalties or retainage shall be imposed on the first offense for violations that directly affect emission reduction benefits. At a minimum, in test-and-repair programs inspector and station license suspension shall be imposed for at least 6 months whenever a vehicle is intentionally improperly passed for any required portion of the test. In test-only programs, inspectors shall be removed from inspector duty for at least 6 months (or a retainage penalty equivalent to the inspector's salary for that period shall be imposed).
(3) All findings of serious violations of rules or procedural requirements shall result in mandatory fines or retainage. In the case of gross neglect, a first offense shall result in a fine or retainage of no less than $100 or 5 times the inspection fee, whichever is greater, for the contractor or the licensed station, and the inspector if involved.
(4) Any finding of inspector incompetence shall result in mandatory training before inspection privileges are restored.
(5) License or certificate suspension or revocation shall mean the individual is barred from direct or indirect involvement in any inspection operation during the term of the suspension or revocation.
(b)
(2) The oversight agency shall have the authority to impose penalties against the licensed station or contractor, as well as the inspector, even if the licensee or contractor had no direct knowledge of the violation but was
(c)
(d)
(2) In the case of State constitutional impediments to immediate suspension authority, the State Attorney General shall furnish an official opinion for the SIP explaining the constitutional impediment as well as relevant case law.
(3) The SIP shall describe the administrative and judicial procedures and responsibilities relevant to the enforcement process, including which agencies, courts, and jurisdictions are involved; who will prosecute and adjudicate cases; and other aspects of the enforcement of the program requirements, the resources to be allocated to this function, and the source of those funds. In States without immediate suspension authority, the SIP shall demonstrate that sufficient resources, personnel, and systems are in place to meet the three day case management requirement for violations that directly affect emission reductions.
(e) Alternative quality assurance procedures or frequencies that achieve equivalent or better results may be approved by the Administrator. Statistical process control shall be used whenever possible to demonstrate the efficacy of alternatives.
(f) Areas that qualify for and choose to implement an OTR low enhanced I/M program, as established in § 51.351(h), and that claim in their SIP less emission reduction credit than the basic performance standard for one or more pollutants, are not required to meet the oversight specifications of this section.
Accurate data collection is essential to the management, evaluation, and enforcement of an I/M program. The program shall gather test data on individual vehicles, as well as quality control data on test equipment.
(a)
(1) Test record number;
(2) Inspection station and inspector numbers;
(3) Test system number;
(4) Date of the test;
(5) Emission test start time and the time final emission scores are determined;
(6) Vehicle Identification Number;
(7) License plate number;
(8) Test certificate number;
(9) Gross Vehicle Weight Rating (GVWR);
(10) Vehicle model year, make, and type;
(11) Number of cylinders or engine displacement;
(12) Transmission type;
(13) Odometer reading;
(14) Category of test performed (i.e., initial test, first retest, or subsequent retest);
(15) Fuel type of the vehicle (i.e., gas, diesel, or other fuel);
(16) Type of vehicle preconditioning performed (if any);
(17) Emission test sequence(s) used;
(18) Hydrocarbon emission scores and standards for each applicable test mode;
(19) Carbon monoxide emission scores and standards for each applicable test mode;
(20) Carbon dioxide emission scores (CO+CO
(21) Nitrogen oxides emission scores and standards for each applicable test mode;
(22) Results (Pass/Fail/Not Applicable) of the applicable visual inspections for the catalytic converter, air system, gas cap, evaporative system, positive crankcase ventilation (PCV) valve, fuel inlet restrictor, and any other visual inspection for which emission reduction credit is claimed;
(23) Results of the evaporative system pressure test expressed as a pass or fail;
(24) Results of the evaporative system purge test expressed as a pass or fail along with the total purge flow in liters achieved during the test; and
(25) Results of the on-board diagnostic check expressed as a pass or fail along with the diagnostic trouble codes revealed.
(b)
Data analysis and reporting are required to allow for monitoring and evaluation of the program by program management and EPA, and shall provide information regarding the types of program activities performed and their final outcomes, including summary statistics and effectiveness evaluations of the enforcement mechanism, the quality assurance system, the quality control program, and the testing element. Initial submission of the following annual reports shall commence within 18 months of initial implementation of the program as required by § 51.373 of this subpart. The biennial report shall commence within 30 months of initial implementation of the program as required by § 51.373 of this subpart.
(a)
(1) The number of vehicles tested by model year and vehicle type;
(2) By model year and vehicle type, the number and percentage of vehicles:
(i) Failing the emissions test initially;
(ii) Failing each emission control component check initially;
(iii) Failing the evaporative system functional and integrity checks initially;
(iv) Failing the first retest for tailpipe emissions;
(v) Passing the first retest for tailpipe emissions;
(vi) Initially failed vehicles passing the second or subsequent retest for tailpipe emissions;
(vii) Initially failed vehicles passing each emission control component check on the first or subsequent retest by component;
(viii) Initially failed vehicles passing the evaporative system functional and integrity checks on the first or subsequent retest by component;
(ix) Initially failed vehicles receiving a waiver;
(x) Vehicles with no known final outcome (regardless of reason);
(xi) Passing the on-board diagnostic check and failing the I/M emission test;
(xii) Failing the on-board diagnostic check and passing the I/M emission test;
(xiii) Passing both the on-board diagnostic check and I/M emission test;
(xiv) Failing both the on-board diagnostic check and I/M emission test;
(xv) Passing the on-board diagnostic check and failing the I/M evaporative test;
(xvi) Failing the on-board diagnostic check and passing the I/M evaporative test;
(xvii) Passing both the on-board diagnostic check and I/M evaporative test;
(xviii) Failing both the on-board diagnostic check and I/M evaporative test;
(xix) MIL is commanded on and no codes are stored;
(xx) MIL is not commanded on and codes are stored;
(xxi) MIL is commanded on and codes are stored;
(xxii) MIL is not commanded on and codes are not stored;
(xxiii) Readiness status indicates that the evaluation is not complete for any module supported by on-board diagnostic systems;
(3) The initial test volume by model year and test station;
(4) The initial test failure rate by model year and test station; and
(5) The average increase or decrease in tailpipe emission levels for HC, CO, and NO
(b)
(1) The number of inspection stations and lanes:
(i) Operating throughout the year; and
(ii) Operating for only part of the year;
(2) The number of inspection stations and lanes operating throughout the year:
(i) Receiving overt performance audits in the year;
(ii) Not receiving overt performance audits in the year;
(iii) Receiving covert performance audits in the year;
(iv) Not receiving covert performance audits in the year; and
(v) That have been shut down as a result of overt performance audits;
(3) The number of covert audits:
(i) Conducted with the vehicle set to fail the emission test;
(ii) Conducted with the vehicle set to fail the component check;
(iii) Conducted with the vehicle set to fail the evaporative system checks;
(iv) Conducted with the vehicle set to fail any combination of two or more of the above checks;
(v) Resulting in a false pass for emissions;
(vi) Resulting in a false pass for component checks;
(vii) Resulting in a false pass for the evaporative system check; and
(viii) Resulting in a false pass for any combination of two or more of the above checks;
(4) The number of inspectors and stations:
(i) That were suspended, fired, or otherwise prohibited from testing as a result of covert audits;
(ii) That were suspended, fired, or otherwise prohibited from testing for other causes; and
(iii) That received fines;
(5) The number of inspectors licensed or certified to conduct testing;
(6) The number of hearings:
(i) Held to consider adverse actions against inspectors and stations; and
(ii) Resulting in adverse actions against inspectors and stations;
(7) The total amount collected in fines from inspectors and stations by type of violation;
(8) The total number of covert vehicles available for undercover audits over the year; and
(9) The number of covert auditors available for undercover audits.
(c)
(1) The number of emission testing sites and lanes in use in the program;
(2) The number of equipment audits by station and lane;
(3) The number and percentage of stations that have failed equipment audits; and
(4) Number and percentage of stations and lanes shut down as a result of equipment audits.
(d)
(i) An estimate of the number of vehicles subject to the inspection program, including the results of an analysis of the registration data base;
(ii) The percentage of motorist compliance based upon a comparison of the number of valid final tests with the number of subject vehicles;
(iii) The total number of compliance documents issued to inspection stations;
(iv) The number of missing compliance documents;
(v) The number of time extensions and other exemptions granted to motorists; and
(vi) The number of compliance surveys conducted, number of vehicles surveyed in each, and the compliance rates found.
(2) Registration denial based enforcement programs shall provide the following additional information:
(i) A report of the program's efforts and actions to prevent motorists from falsely registering vehicles out of the program area or falsely changing fuel type or weight class on the vehicle registration, and the results of special studies to investigate the frequency of such activity; and
(ii) The number of registration file audits, number of registrations reviewed, and compliance rates found in such audits.
(3) Computer-matching based enforcement programs shall provide the following additional information:
(i) The number and percentage of subject vehicles that were tested by the initial deadline, and by other milestones in the cycle;
(ii) A report on the program's efforts to detect and enforce against motorists falsely changing vehicle classifications to circumvent program requirements, and the frequency of this type of activity; and
(iii) The number of enforcement system audits, and the error rate found during those audits.
(4) Sticker-based enforcement systems shall provide the following additional information:
(i) A report on the program's efforts to prevent, detect, and enforce against sticker theft and counterfeiting, and the frequency of this type of activity;
(ii) A report on the program's efforts to detect and enforce against motorists falsely changing vehicle classifications to circumvent program requirements, and the frequency of this type of activity; and
(iii) The number of parking lot sticker audits conducted, the number of vehicles surveyed in each, and the noncompliance rate found during those audits.
(e)
(1) Any changes made in program design, funding, personnel levels, procedures, regulations, and legal authority, with detailed discussion and evaluation of the impact on the program of all such changes; and
(2) Any weaknesses or problems identified in the program within the two-year reporting period, what steps have already been taken to correct those problems, the results of those steps, and any future efforts planned.
(f)
All inspectors shall receive formal training and be licensed or certified to perform inspections.
(a)
(i) The air pollution problem, its causes and effects;
(ii) The purpose, function, and goal of the inspection program;
(iii) Inspection regulations and procedures;
(iv) Technical details of the test procedures and the rationale for their design;
(v) Emission control device function, configuration, and inspection;
(vi) Test equipment operation, calibration, and maintenance;
(vii) Quality control procedures and their purpose;
(viii) Public relations; and
(ix) Safety and health issues related to the inspection process.
(2) If inspector training is not administered by the program, the responsible
(3) In order to complete the training requirement, a trainee shall pass (i.e., a minimum of 80% of correct responses or lower if an occupational analysis justifies it) a written test covering all aspects of the training. In addition, a hands-on test shall be administered in which the trainee demonstrates without assistance the ability to conduct a proper inspection, to properly utilize equipment and to follow other procedures. Inability to properly conduct all test procedures shall constitute failure of the test. The program shall take appropriate steps to insure the security and integrity of the testing process.
(b)
(2) Completion of inspector training and passing required tests shall be a condition of licensing or certification.
(3) Inspector licenses and certificates shall be valid for no more than 2 years, at which point refresher training and testing shall be required prior to renewal. Alternative approaches based on more comprehensive skill examination and determination of inspector competency may be used.
(4) Licenses or certificates shall not be considered a legal right but rather a privilege bestowed by the program conditional upon adherence to program requirements.
(c)
(a)
(b)
Effective repairs are the key to achieving program goals and the State shall take steps to ensure the capability exists in the repair industry to repair vehicles that fail I/M tests.
(a)
(1) The agency shall regularly inform repair facilities of changes in the inspection program, training course schedules, common problems being found with particular engine families, diagnostic tips and the like.
(2) The agency shall provide a hot line service to assist repair technicians with specific repair problems, answer technical questions that arise in the repair process, and answer questions related to the legal requirements of State and Federal law with regard to
(b)
(2) Programs shall provide feedback, including statistical and qualitative information to individual repair facilities on a regular basis (at least annually) regarding their success in repairing failed vehicles.
(3) A prerequisite for a retest shall be a completed repair form that indicates which repairs were performed, as well as any technician recommended repairs that were not performed, and identification of the facility that performed the repairs.
(c)
(1) Diagnosis and repair of malfunctions in computer controlled, close-loop vehicles;
(2) The application of emission control theory and diagnostic data to the diagnosis and repair of failures on the transient emission test and the evaporative system functional checks;
(3) Utilization of diagnostic information on systematic or repeated failures observed in the transient emission test and the evaporative system functional checks; and
(4) General training on the various subsystems related to engine emission control.
(d)
States shall establish methods to ensure that vehicles subject to enhanced I/M and that are included in either a “Voluntary Emissions Recall” as defined at 40 CFR 85.1902(d), or in a remedial plan determination made pursuant to section 207(c) of the Act, receive the required repairs. States shall require that owners of recalled vehicles have the necessary recall repairs completed, either in order to complete an annual or biennial inspection process or to obtain vehicle registration renewal. All recalls for which owner notification occurs after January 1, 1995 shall be included in the enhanced I/M recall requirement.
(a)
(2) The State shall require owners or lessees of vehicles with unresolved recalls to show proof of compliance with
(3) Compliance shall be required on the next registration or inspection date, allowing a reasonable period to comply, after notification of recall was received by the State.
(b)
(2) In the case of vehicles obtaining recall repairs but remaining on the updated list provided in paragraph (a)(1) of this section, the State shall have a means of verifying completion of the required repairs; electronic records or paper receipts provided by the authorized repair facility shall be required. The vehicle inspection or registration record shall be modified to include (or be supplemented with other VIN-linked records which include) the recall campaign number(s) and the date(s) repairs were performed. Documentation verifying required repairs shall include the following:
(i) The VIN, make, and model year of the vehicle; and
(ii) The recall campaign number and the date repairs were completed.
(c)
(1) The number of vehicles in the I/M area initially listed as having unresolved recalls, segregated by recall campaign number;
(2) The number of recalled vehicles brought into compliance by owners;
(3) The number of listed vehicles with unresolved recalls that, as of the end of the calendar year, were not yet due for inspection or registration;
(4) The number of recalled vehicles still in non-compliance that have either failed inspection or been denied registration on the basis of non-compliance with recall; and
(5) The number of recalled vehicles that are otherwise not in compliance.
(d)
On-road testing is defined as the measurement of HC, CO, NO
(a)
(2) On-road testing is not required in every season or on every vehicle but shall evaluate the emission performance of 0.5% of the subject fleet statewide or 20,000 vehicles, whichever is less, including any vehicles that may be subject to the follow-up inspection provisions of paragraph (a)(4) of this section, each inspection cycle.
(3) The on-road testing program shall provide information about the emission performance of in-use vehicles, by measuring on-road emissions through the use of remote sensing devices or roadside pullovers including tailpipe emission testing. The program shall collect, analyze and report on-road testing data.
(4) Owners of vehicles that have previously been through the normal periodic inspection and passed the final retest and found to be high emitters shall be notified that the vehicles are required to pass an out-of-cycle follow-up inspection; notification may be by mailing in the case of remote sensing on-road testing or through immediate notification if roadside pullovers are used.
(b)
(2) The SIP shall include the legal authority necessary to implement the on-road testing program, including the authority to enforce off-cycle inspection and repair requirements.
(3) Emission reduction credit for on-road testing programs shall be granted for a program designed to obtain significant emission reductions over and above those already predicted to be achieved by other aspects of the I/M program. The SIP shall include technical support for the claimed additional emission reductions.
(a)
(1) A schedule of implementation of the program including interim milestones leading to mandatory testing. The milestones shall include, at a minimum:
(i) Passage of enabling statutory or other legal authority;
(ii) Proposal of draft regulations and promulgation of final regulations;
(iii) Issuance of final specifications and procedures;
(iv) Issuance of final Request for Proposals (if applicable);
(v) Licensing or certifications of stations and inspectors;
(vi) The date mandatory testing will begin for each model year to be covered by the program;
(vii) The date full-stringency cutpoints will take effect;
(viii) All other relevant dates;
(2) An analysis of emission level targets for the program using the most current EPA mobile source emission model or an alternative approved by the Administrator showing that the program meets the performance standard described in § 51.351 or § 51.352 of this subpart, as applicable;
(3) A description of the geographic coverage of the program, including ZIP codes if the program is not county-wide;
(4) A detailed discussion of each of the required design elements, including provisions for Federal facility compliance;
(5) Legal authority requiring or allowing implementation of the I/M program and providing either broad or specific authority to perform all required elements of the program;
(6) Legal authority for I/M program operation until such time as it is no longer necessary (i.e., until a Section 175 maintenance plan without an I/M program is approved by EPA);
(7) Implementing regulations, interagency agreements, and memoranda of understanding; and
(8) Evidence of adequate funding and resources to implement all aspects of the program.
(b)
(1) States shall submit a SIP revision by November 15, 1992 which includes the schedule required in paragraph (a)(1) of this section and a formal commitment from the Governor to the adoption and implementation of an I/M program meeting all requirements of this subpart.
(2) A SIP revision, including all necessary legal authority and the items specified in (a)(1) through (a)(8) of this section, shall be submitted no later than November 15, 1993.
(3) States shall revise SIPS as EPA develops further regulations. Revisions to incorporate on-board diagnostic checks in the I/M program shall be submitted by August 6, 1998.
(c)
(1) Legal authority to implement a basic I/M program (or enhanced if the State chooses to opt up) as required by this subpart. The legislative authority for an I/M program shall allow the adoption of implementing regulations without requiring further legislation.
(2) A request to place the I/M plan (if no I/M program is currently in place or
(3) A contingency measure consisting of a commitment by the Governor or the Governor's designee to adopt or consider adopting regulations to implement an I/M program to correct a violation of the ozone or CO standard or other air quality problem, in accordance with the provisions of the maintenance plan.
(4) A contingency commitment that includes an enforceable schedule for adoption and implementation of the I/M program, and appropriate milestones. The schedule shall include the date for submission of a SIP meeting all of the requirements of this subpart. Schedule milestones shall be listed in months from the date EPA notifies the State that it is in violation of the ozone or CO standard or any earlier date specified in the State plan. Unless the State, in accordance with the provisions of the maintenance plan, chooses not to implement I/M, it must submit a SIP revision containing an I/M program no more than 18 months after notification by EPA.
(d) Basic areas continuing operation of I/M programs as part of their maintenance plan without implemented upgrades shall be assumed to be 80% as effective as an implemented, upgraded version of the same I/M program design, unless a State can demonstrate using operating information that the I/M program is more effective than the 80% level.
(e)
I/M programs shall be implemented as expeditiously as practicable.
(a) Decentralized basic programs shall be fully implemented by January 1, 1994, and centralized basic programs shall be fully implemented by July 1, 1994. More implementation time may be approved by the Administrator if an enhanced I/M program is implemented.
(b) For areas newly required to implement basic I/M after promulgation of this subpart (as a result of failure to attain, reclassification, or redesignation) decentralized programs shall be fully implemented within one year of obtaining legal authority. Centralized programs shall be fully implemented within two years of obtaining legal authority. More implementation time may be approved by the Administrator if an enhanced I/M program is implemented.
(c) All requirements related to enhanced I/M programs shall be implemented by January 1, 1995, with the following exceptions.
(1) Areas switching from an existing test-and-repair network to a test-only network may phase in the change between January of 1995 and January of 1996. Starting in January of 1995 at least 30% of the subject vehicles shall participate in the test-only system (in States with multiple I/M areas, implementation is not required in every area by January 1995 as long as statewide, 30% of the subject vehicles are involved in testing) and shall be subject to the new test procedures (including the evaporative system checks, visual inspections, and tailpipe emission tests).
(2) Areas starting new test-only programs and those with existing test-only programs may also phase in the new test procedures between January 1, 1995 and January 1, 1996. Other program requirements shall be fully implemented by January 1, 1995.
(d) In the case of areas newly required to implement enhanced I/M after promulgation of this subpart (as a result of failure to attain, reclassification, or nonattainment designation) enhanced I/M shall be implemented within 24 months of obtaining legal authority.
(e) Legal authority for the implementing agency or agencies to implement and enforce an I/M program consistent with this subpart shall be obtained from the State legislature or local governing body in the first legislative session after November 5, 1992, or after being newly required to implement or upgrade an I/M program as in paragraph (b) or (c) of this section, including sessions already in progress if at least 21 days remain before the final bill submittal deadline.
(f) Areas that choose to implement an enhanced I/M program only meeting the requirements of § 51.351(h) shall fully implement the program no later than July 1, 1999. The availability and use of this late start date does not relieve the area of the obligation to meet the requirements of § 51.351(h)(11) by the end of 1999.
(g) On-Board Diagnostic checks shall be implemented in all basic, low enhanced and high enhanced areas as part of the I/M program by January 1, 2001.
States may opt to use transient emission test equipment for steady-state tests and follow the quality control requirements in paragraph (II) of this appendix instead of the following requirements.
(a) Equipment shall be calibrated in accordance with the manufacturers' instructions.
(b)
(2)
(3)
(c)
(d)
(2)
(3)
(e)
(2)
(f)
(1)
(B) In high-volume stations, monthly multi-point calibrations shall be performed. Low-volume stations shall perform multi-point calibrations every six months. The calibration curve shall be checked at 20%, 40%, 60%, and 80% of full scale and adjusted or repaired if the specifications in appendix D(I)(b)(1) to this subpart are not met.
(2)
(a)
(b)
(2) The sample probe shall be cleaned and checked at least once per month. The main CVS venturi shall be cleaned and checked at least once per year.
(3) Verification that flow through the sample probe is adequate for the design shall be done daily. Deviations greater than the design tolerances shall be corrected.
(c)
(B) For all calibration curves, curve checks, span adjustments, and span checks, the zero gas shall be considered a down-scale reference gas, and the analyzer zero shall be set at the trace concentration value of the specific zero gas used.
(2) The basic curve shall be checked monthly by the same procedure used to generate the curve, and to the same tolerances.
(3) On a daily basis prior to vehicle testing—
(A) The curve for each analyzer shall be checked by adjusting the analyzer to correctly read a zero gas and an up-scale span gas, and then by correctly reading a mid-scale span gas within 2% of point. If the analyzer does not read the mid-scale span point within 2% of point, the system shall lock out. The up-scale span gas concentration for each analyzer shall correspond to approximately 80 percent of full scale, and the mid-point concentration shall correspond to approximately 15 percent of full scale; and
(B) After the up-scale span check, each analyzer in a given facility shall analyze a sample of a random concentration corresponding to approximately 0.5 to 3 times the cut point (in gpm) for the constituent. The value of the random sample may be determined by a gas blender. The deviation in analysis from the sample concentration for each analyzer shall be recorded and compared to the historical mean and standard deviation for the analyzers at the facility and at all facilities. Any reading exceeding 3 sigma shall cause the analyzer to lock out.
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
On a daily basis each purge flow meter shall be checked with a simulated purge flow against a reference flow measuring device with performance specifications equal to or better than those specified for the purge meter. The check shall include a mid-scale rate check, and a total flow check between 10 and 20 liters. Deviations greater than
(a) On a weekly basis pressure measurement devices shall be checked against a reference device with performance specifications equal to or better than those specified for the measurement device. Deviations exceeding the performance specifications shall be corrected. Flow measurement devices, if any, shall be checked according to paragraph III of this appendix.
(b) Systems that monitor evaporative system leaks shall be checked for integrity on a daily basis by sealing and pressurizing.
(a)
(2)
(3)
(4)
(5) This test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(i) The first-chance test, as described under paragraph (c) of this section, shall consist of an idle mode.
(ii) The second-chance test as described under paragraph (I)(d) of this appendix shall be performed only if the vehicle fails the first-chance test.
(2) The test sequence shall begin only after the following requirements are met:
(i) The vehicle shall be tested in as-received condition with the transmission in neutral or park and all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(ii) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor RPM. In the event that an OBD data link connector is not available or that an RPM signal is not available over the data link connector, a tachometer shall be used instead.
(iii) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(iv) The measured concentration of CO plus CO
(c)
(1) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset zero and resume timing. The minimum mode length shall be determined as described under paragraph (I)(c)(2) of this appendix. The maximum mode length shall be 90 seconds elapsed time (mt=90).
(2) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(i) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(ii) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30), if prior to that time the criteria of paragraph (I)(c)(2)(i) of this appendix are not satisfied and the measured values are less than or equal to the applicable short test standards as described in paragraph (I)(a)(2) of this appendix.
(iii) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (I)(a)(2) of this appendix.
(iv) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (I)(c)(2)(i), (ii) and (iii) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90). Alternatively, the vehicle may be failed if the provisions of paragraphs (I)(c)(2)(i) and (ii) of this appendix are not met within an elapsed time of 30 seconds.
(v)
(d)
(1)
(2)
(ii) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset to zero and resume timing. The minimum idle mode length shall be determined as described in paragraph (I)(d)(2)(iii) of this appendix. The maximum idle mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the idle mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30), if prior to that time the criteria of paragraph (I)(d)(2)(iii)(A) of this appendix are not satisfied and the measured values are less than or equal to the applicable short test standards as described in paragraph (I)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards described in paragraph (I)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (I)(d)(2)(iii)(A), (d)(2)(iii)(B), and (d)(2)(iii)(C) of this appendix are satisfied by an elapsed time of 90 seconds (mt=90).
(a)
(2)
(3)
(4)
(5) The test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(i) The first-chance test, as described under paragraph (II)(c) of this appendix, shall consist of an idle mode followed by a high-speed mode.
(ii) The second-chance high-speed mode, as described under paragraph (II)(c) of this appendix, shall immediately follow the first-chance high-speed mode. It shall be performed only if the vehicle fails the first-chance test. The second-chance idle mode, as described under paragraph (II)(d) of this appendix, shall follow the second-chance high-speed mode and be performed only if the vehicle fails the idle mode of the first-chance test.
(2) The test sequence shall begin only after the following requirements are met:
(i) The vehicle shall be tested in as-received condition with the transmission in neutral or park and all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(ii) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor RPM. In the event that an OBD data link connector is not available or that an RPM signal is not available over the data link connector, a tachometer shall be used instead.
(iii) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(iv) The measured concentration of CO plus CO
(c)
(1)
(ii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode terminated as follows:
(A) The vehicle shall pass the idle mode and the mode shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the mode shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (II)(c)(1)(ii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (II)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the mode shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (II)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the mode shall be terminated if none of the provisions of paragraphs (II)(c)(1)(ii)(A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90). Alternatively, the vehicle may be failed if the provisions of paragraphs (II)(c)(2)(i) and (ii) of this appendix are not met within an elapsed time of 30 seconds.
(E)
(2)
(i) The mode timer shall reset (mt=0) when the vehicle engine speed is between 2200 and 2800 rpm. If engine speed falls below 2200 rpm or exceeds 2800 rpm for more than two seconds in one excursion, or more than six seconds over all excursions within 30 seconds of the final measured value used in the pass/fail determination, the measured value shall be invalidated and the mode continued. If any excursion lasts for more than ten seconds, the mode timer shall reset to zero (mt=0) and timing resumed. The minimum high-speed mode length shall be determined as described under paragraphs (II)(c)(2)(ii) and (iii) of this appendix. The maximum high-speed mode length shall be 180 seconds elapsed time (mt=180).
(ii)
(A) A pass or fail determination, as described below, shall be used, for vehicles that passed the idle mode, to determine whether the high-speed test should be terminated prior to or at the end of an elapsed time of 180 seconds (mt=180).
(
(
(
(
(
(
(B) A pass or fail determination shall be made for vehicles that
(
(
(
(
(
(A) A pass or fail determination, as described below, shall be used for vehicles that passed the idle mode, to determine whether the high-speed mode should be terminated prior to or at the end of an elapsed time of 180 seconds (mt=180).
(
(
(
(
(B) A pass or fail determination shall be made for vehicles that
(
(
(d)
(1) The engines of 1981-1987 Ford Motor Company vehicles and 1984-1985 Honda Preludes shall be shut off for not more than 10 seconds and restarted. The probe may be removed from the tailpipe or the sample pump turned off if necessary to reduce analyzer fouling during the restart procedure. This procedure may also be used for 1988-1989 Ford Motor Company vehicles but should not be used for other vehicles.
(2) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If the engine speed exceeds 1100 rpm or falls below 350 rpm the mode timer shall reset to zero and resume timing. The minimum second-chance idle mode length
(3) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the second-chance idle mode shall be terminated as follows:
(i) The vehicle shall pass the second-chance idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), any measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(ii) The vehicle shall pass the second-chance idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (II)(d)(3)(i) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (II)(a)(2) of this appendix.
(iii) The vehicle shall pass the second-chance idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (II)(a)(2) of this appendix.
(iv) The vehicle shall fail the second-chance idle mode and the test shall be terminated if none of the provisions of paragraph (II)(d)(3)(i), (ii), and (iii) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90).
(a)
(2)
(3)
(4)
(5) The test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(2) The test sequence shall begin only after the following requirements are met:
(i) The dynamometer shall be warmed up, in stabilized operating condition, adjusted, and calibrated in accordance with the procedures of appendix A to this subpart. Prior to each test, variable-curve dynamometers shall be checked for proper setting of the road-load indicator or road-load controller.
(ii) The vehicle shall be tested in as-received condition with all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(iii) The vehicle shall be operated during each mode of the test with the gear selector in the following position:
(A) In drive for automatic transmissions and in second (or third if more appropriate) for manual transmissions for the loaded mode;
(B) In park or neutral for the idle mode.
(iv) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor RPM. In the event that an OBD data link connector is not available or that an RPM signal is not available over the data link connector, a tachometer shall be used instead.
(v) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(vi) The measured concentration of CO plus CO
(c)
(1)
(ii) The mode timer shall start (mt=0) when the dynamometer speed is within the limits specified for the vehicle engine size according to the following schedule. If the dynamometer speed falls outside the limits for more than five seconds in one excursion, or 15 seconds over all excursions, the mode timer shall reset to zero and resume timing. The minimum mode length shall be determined as described in paragraph (III)(c)(1)(iii)(A) of this appendix. The maximum mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the loaded mode and the mode shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards described in paragraph (a)(2) of this section.
(B) The vehicle shall fail the loaded mode and the mode shall be terminated if paragraph (III)(c)(1)(iii)(A) of this appendix is not satisfied by an elapsed time of 90 seconds (mt=90).
(C)
(2)
(ii) The mode timer shall start (mt=0) when the dynamometer speed is zero and the vehicle engine speed is between 350 and 1100 rpm. If engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset to zero and resume timing. The minimum idle mode length shall be determined as described in paragraph (II)(c)(2)(ii) of this appendix. The maximum idle mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (III)(c)(2)(iii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (III)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards described in paragraph (III)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (III)(c)(2)(iii)(A), (c)(2)(iii)(B), and (c)(2)(iii)(C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90).
(a)
(2)
(3)
(4)
(5) The test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(i) The first-chance test, as described under paragraph (IV)(c) of this appendix, shall consist of a preconditioning mode followed by an idle mode.
(ii) The second-chance test, as described under paragraph (IV)(d) of this appendix, shall be performed only if the vehicle fails the first-chance test.
(2) The test sequence shall begin only after the following requirements are met:
(i) The vehicle shall be tested in as-received condition with the transmission in neutral or park and all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(ii) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor RPM. In the event that an OBD data link connector is not available or that an RPM signal is not available over the data link connector, a tachometer shall be used instead.
(iii) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(iv) The measured concentration of CO plus CO2 shall be greater than or equal to six percent.
(c)
(1)
(2)
(ii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (IV)(c)(2)(ii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (IV)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards as described in paragraph (IV)(a)(2) of this section.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (IV)(c)(2)(ii)(A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90). Alternatively, the vehicle may be failed if the provisions of paragraphs (IV)(c)(2) (i) and (ii) of this appendix are not met within an elapsed time of 30 seconds.
(E)
(d)
(1)
(2)
(ii) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If the engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset to zero and resume timing. The minimum idle mode length shall be determined as described in paragraph (IV)(d)(2)(iii) of this appendix. The maximum idle mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (IV)(d)(2)(iii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (IV)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards described in paragraph (IV)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (IV)(d)(2)(iii) (A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90).
(a)
(2)
(3)
(4)
(5) The test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(i) The first-chance test, as described under paragraph (V)(c) of this appendix, shall consist of an idle mode.
(ii) The second-chance test as described under paragraph (V)(d) of this appendix shall be performed only if the vehicle fails the first-chance test.
(2) The test sequence shall begin only after the following requirements are met:
(i) The dynamometer shall be warmed up, in stabilized operating condition, adjusted, and calibrated in accordance with the procedures of appendix A to this subpart. Prior to each test, variable-curve dynamometers shall be checked for proper setting of the road-load indicator or road-load controller.
(ii) The vehicle shall be tested in as-received condition with all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(iii) The vehicle shall be operated during each mode of the test with the gear selector in the following position:
(A) In drive for automatic transmissions and in second (or third if more appropriate) for manual transmissions for the loaded preconditioning mode;
(B) In park or neutral for the idle mode.
(iv) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor RPM. In the event that an OBD data link connector is not available or that an RPM signal is not available over the data link connector, a tachometer shall be used instead.
(v) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(vi) The measured concentration of CO plus CO
(c)
(1) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If the engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset to zero and resume timing. The minimum mode length shall be determined as described in paragraph (V)(c)(2) of this appendix. The maximum mode length shall be 90 seconds elapsed time (mt=90).
(2) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(i) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(ii) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (V)(c)(2)(i) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (V)(a)(2) of this appendix.
(iii) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (V)(a)(2) of this appendix.
(iv) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (V)(c)(2)(i), (ii), and (iii) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90). Alternatively, the vehicle may be failed if the provisions of paragraphs (V)(c)(2) (i) and (ii) of this appendix are not met within an elapsed time of 30 seconds.
(v)
(d)
(1)
(2)
(ii) The mode timer shall start (mt=0) when the dynamometer speed is zero and the vehicle engine speed is between 350 and 1100 rpm. If the engine speed exceeds 1100 rpm or falls below 350 rpm, the mode timer shall reset to zero and resume timing. The minimum idle mode length shall be determined as described in paragraph (V)(d)(2)(ii) of this appendix. The maximum idle mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (V)(d)(2)(ii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (V)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (V)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (V)(d)(2)(ii)(A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90).
(a)
(2)
(3)
(4)
(5) The test shall be immediately terminated upon reaching the overall maximum test time.
(b)
(i) The first-chance test, as described under paragraph (VI)(c) of this appendix, shall consist of a first-chance high-speed mode followed immediately by a first-chance idle mode.
(ii) The second-chance test as described under paragraph (VI)(d) of this appendix shall be performed only if the vehicle fails the first-chance test.
(2) The test sequence shall begin only after the following requirements are met:
(i) The vehicle shall be tested in as-received condition with the transmission in neutral or park and all accessories turned off. The engine shall be at normal operating temperature (as indicated by a temperature gauge, temperature lamp, touch test on the radiator hose, or other visual observation for overheating).
(ii) For all pre-1996 model year vehicles, a tachometer shall be attached to the vehicle in accordance with the analyzer manufacturer's instructions. For 1996 and newer model year vehicles the OBD data link connector will be used to monitor rpm. In the event that an OBD data link connector is not available or that an rpm signal is not available over the data link connector, a tachometer shall be used instead.
(iii) The sample probe shall be inserted into the vehicle's tailpipe to a minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to this depth, a tailpipe extension shall be used.
(iv) The measured concentration of CO plus CO
(c)
(1)
(ii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the high-speed mode and the mode shall be terminated at an elapsed time of 90 seconds (mt=90) if any measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(B) The vehicle shall fail the high-speed mode and the mode shall be terminated if the requirements of paragraph (VI)(c)(1)(ii)(A) of this appendix are not satisfied by an elapsed time of 90 seconds (mt=90).
(C)
(2)
(ii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (VI)(c)(2)(ii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(C) The vehicle shall pass the idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), the measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(D) The vehicle shall fail the idle mode and the test shall be terminated if none of the provisions of paragraphs (VI)(c)(2)(ii) (A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90). Alternatively, the vehicle may be failed if the provisions of paragraphs (VI)(c)(2)(i) and (ii) of this appendix are not met within the elapsed time of 30 seconds.
(d)
(A) If the vehicle failed only the first-chance high-speed mode, the second-chance test shall consist of a second-chance high-speed mode as described in paragraph (VI)(d)(2) of this appendix. The overall maximum test time shall be 280 seconds (tt=280).
(B) If the vehicle failed only the first-chance idle mode, the second-chance test shall consist of a second-chance pre-conditioning mode followed immediately by a second-chance idle mode as described in paragraphs (VI)(d) (3) and (4) of this appendix. The overall maximum test time shall be 425 seconds (tt=425).
(C) If both the first-chance high-speed mode and first-chance idle mode were failed, the second-chance test shall consist of the second-chance high-speed mode followed immediately by the second-chance idle mode as described in paragraphs (VI)(d) (2) and (4) of this appendix. However, if during this second-chance procedure the vehicle fails the second-chance high-speed mode, then the second-chance idle mode may be eliminated. The overall maximum test time shall be 425 seconds (tt=425).
(2)
(ii) The mode timer shall reset (mt=0) when the vehicle engine speed is between 2200 and 2800 rpm. If the engine speed falls below 2200 rpm or exceeds 2800 rpm for more than two seconds in one excursion, or more than six seconds over all excursions within 30 seconds of the final measured value used in the pass/fail determination, the measured value shall be invalidated and the mode continued. The minimum second-chance high-speed mode length shall be determined as described in paragraphs (VI)(d)(2) (iii) and (iv) of this appendix. If any excursion lasts for more than ten seconds, the mode timer shall reset to zero (mt=0) and timing resumed. The maximum second-chance high-speed mode length shall be 180 seconds elapsed time (mt=180).
(iii) In the case where the second-chance high-speed mode is
(A) The vehicle shall pass the high-speed mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the high-speed mode and the test shall be terminated if at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (VI)(d)(2)(iii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(C) The vehicle shall pass the high-speed mode and the test shall be immediately terminated if, at any point between an elapsed time for 30 seconds (mt=30) and 180 seconds (mt=180), the measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(D) The vehicle shall fail the high-speed mode and the test shall be terminated if none of the provisions of paragraphs (VI)(d)(2)(iii) (A), (B), and (C) of this appendix is satisfied by an elapsed time of 180 seconds (mt=180).
(iv) In the case where the second-chance high-speed mode
(A) The vehicle shall pass the high-speed mode and the mode shall be terminated at the end of an elapsed time of 180 seconds (mt=180) if any measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(B) The vehicle shall fail the high-speed mode and the mode shall be terminated if paragraph (VI)(d)(2)(iv)(A) of this appendix is not satisfied by an elapsed time of 180 seconds (mt=180).
(3)
(4)
(ii) The mode timer shall start (mt=0) when the vehicle engine speed is between 350 and 1100 rpm. If the engine exceeds 1100 rpm or falls below 350 rpm the mode timer shall reset to zero and resume timing. The minimum second-chance idle mode length shall be determined as described in paragraph (VI)(d)(4)(iii) of this appendix. The maximum second-chance idle mode length shall be 90 seconds elapsed time (mt=90).
(iii) The pass/fail analysis shall begin after an elapsed time of 10 seconds (mt=10). A pass or fail determination shall be made for the vehicle and the mode shall be terminated as follows:
(A) The vehicle shall pass the second-chance idle mode and the test shall be immediately terminated if, prior to an elapsed time of 30 seconds (mt=30), measured values are less than or equal to 100 ppm HC and 0.5 percent CO.
(B) The vehicle shall pass the second-chance idle mode and the test shall be terminated at the end of an elapsed time of 30 seconds (mt=30) if, prior to that time, the criteria of paragraph (VI)(d)(4)(iii)(A) of this appendix are not satisfied, and the measured values are less than or equal to the applicable short test standards as described in paragraph (VI)(a)(2) of this appendix.
(C) The vehicle shall pass the second-chance idle mode and the test shall be immediately terminated if, at any point between an elapsed time of 30 seconds (mt=30) and 90 seconds (mt=90), measured values are less than or equal to the applicable short test standards described in paragraph (VI)(a)(2) of this appendix.
(D) The vehicle shall fail the second-chance idle mode and the test shall be terminated if none of the provisions of paragraphs (VI)(d)(4)(iii) (A), (B), and (C) of this appendix is satisfied by an elapsed time of 90 seconds (mt=90).
For 1981 and later model year light-duty vehicles for which any of the test procedures described in appendix B to this subpart are utilized to establish Emissions Performance Warranty eligibility (i.e., 1981 and later model year light-duty vehicles at low altitude and 1982 and later model year vehicles at high altitude to which high altitude certification standards of 1.5 gpm HC and 15 gpm CO or less apply), short test emissions for all tests and test modes shall not exceed:
(a) Hydrocarbons: 220 ppm as hexane.
(b) Carbon monoxide: 1.2%.
For 1981 and later model year light-duty trucks for which any of the test procedures described in appendix B to this subpart are utilized to establish Emissions Performance Warranty eligibility (i.e., 1981 and later model year light-duty trucks at low altitude and 1982 and later model year trucks at high altitude to which high altitude certification standards of 2.0 gpm HC and 26 gpm CO or less apply), short test emissions for all tests and test modes shall not exceed:
(a) Hydrocarbons: 220 ppm as hexane.
(b) Carbon monoxide: 1.2%.
(a)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(b)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(c)
(a) The chassis dynamometer for steady-state short tests shall provide the following capabilities:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(b) The dynamometer shall produce the load speed relationships specified in paragraphs (III) and (V) of appendix B to this subpart.
(I)
(II)
(a) States with areas subject to this subpart and part 93, subpart A, of this chapter must submit to the EPA and DOT a revision to their implementation plan which contains criteria and procedures for DOT, MPOs and other State or local agencies to assess the conformity of transportation plans, programs, and projects, consistent with this subpart and part 93, subpart A, of this chapter. This revision is to be submitted by November 25, 1994 (or within 12 months of an area's redesignation from attainment to nonattainment, if the State has not previously submitted such a revision). Further revisions to the implementation plan required by amendments to part 93, subpart A, of this chapter must be submitted within 12 months of the date of publication of such final amendments. EPA will provide DOT with a 30-day comment period before taking action to approve or disapprove the submission. A State's conformity provisions may contain criteria and procedures more stringent than the requirements described in this subpart and part 93, subpart A, of this chapter only if the State's conformity provisions apply equally to non-federal as well as Federal entities.
(b) The Federal conformity rules under part 93, subpart A, of this chapter, in addition to any existing applicable State requirements, establish the conformity criteria and procedures necessary to meet the requirements of Clean Air Act section 176(c) until such time as EPA approves the conformity implementation plan revision required by this subpart. Following EPA approval of the State conformity provisions (or a portion thereof) in a revision to the applicable implementation plan, conformity determinations would be governed by the approved (or approved portion of the) State criteria and procedures. The Federal conformity regulations contained in part 93, subpart A, of this chapter would apply only for the portion, if any, of the State's conformity provisions that is not approved by EPA. In addition, any previously applicable implementation plan conformity requirements remain enforceable until the State submits a revision to its applicable implementation plan to specifically remove them and that revision is approved by EPA.
(c) The implementation plan revision required by this section must meet all of the requirements of part 93, subpart A, of this chapter.
(d) In order for EPA to approve the implementation plan revision submitted to EPA and DOT under this subpart, the plan must address all requirements of part 93, subpart A, of this chapter in a manner which gives them full legal effect. In particular, the revision shall incorporate the provisions of the following sections of part 93, subpart A, of this chapter in verbatim form, except insofar as needed to clarify or to give effect to a stated intent in the revision to establish criteria and procedures more stringent than the requirements stated in the following sections of this chapter: §§ 93.101, 93.102, 93.103, 93.104, 93.106, 93.109, 93.110, 93.111, 93.112, 93.113, 93.114, 93.115, 93.116, 93.117, 93.118, 93.119, 93.120, 93.121, 93.126, and 93.127.
(a) The rules in this subpart apply to any statutory economic incentive program (EIP) submitted to the EPA as an implementation plan revision to comply with sections 182(g)(3), 182(g)(5), 187(d)(3), or 187(g) of the Act. Such programs may be submitted by any authorized governmental organization, including States, local governments, and Indian governing bodies.
(b) The provisions contained in these rules, except as explicitly exempted, shall also serve as the EPA's policy guidance on discretionary EIP's submitted as implementation plan revisions for any purpose other than to comply with the statutory requirements specified in paragraph (a) of this section.
(a)
(i) A required milestone compliance demonstration is not submitted within the required period.
(ii) The Administrator determines that the area has not met any applicable milestone.
(2) The plan revision in paragraph (a)(1) of this section shall be submitted within 9 months after such failure or determination, and shall be sufficient, in combination with other elements of the SIP, to achieve the next milestone.
(b)
(i) A milestone demonstration is not submitted within the required period, pursuant to section 187(d) of the Act.
(ii) The Administrator notifies the State, pursuant to section 187(d) of the Act, that a milestone has not been met.
(iii) The Administrator determines, pursuant to section 186(b)(2) of the Act that the NAAQS for CO has not been attained by the applicable date for that area. Such revision shall be submitted within 9 months after such failure or determination.
(2) Submittals made pursuant to paragraphs (b)(1) (i) and (ii) of this section shall be sufficient, together with a transportation control program, to achieve the specific annual reductions in CO emissions set forth in the implementation plan by the attainment date. Submittals made pursuant to paragraph (b)(1)(iii) of this section shall be adequate, in combination with other elements of the revised plan, to reduce the total tonnage of emissions of CO in the area by at least 5 percent per year in each year after approval of the plan revision and before attainment of the NAAQS for CO.
(c)
(d)
Economic incentive programs shall be State and federally enforceable, nondiscriminatory, and consistent with the timely attainment of NAAQS, all applicable RFP and visibility requirements, applicable PSD increments, and all other applicable requirements of the Act. Programs in nonattainment areas for which credit is taken in attainment and RFP demonstrations shall be designed to ensure that the effects of the program are quantifiable and permanent over the entire duration of the program, and that the credit taken is limited to that which is surplus. Statutory programs shall be designed to result in quantifiable, significant reductions in actual emissions. The EIP's shall include the following elements, as applicable:
(a)
(1) The statement of goals must include the goal that the program will benefit both the environment and the regulated entities. The program shall be designed so as to meaningfully meet this goal either directly, through increased or more rapid emissions reductions beyond those that would be achieved through a traditional regulatory program, or, alternatively, through other approaches that will result in real environmental benefits. Such alternative approaches include, but are not limited to, improved administrative mechanisms, reduced administrative burdens on regulatory agencies, improved emissions inventories, and the adoption of emission caps which over time constrain or reduce growth-related emissions beyond traditional regulatory approaches.
(2) The incentive-based strategy shall be described in terms of one of the following three strategies:
(i) Emission-limiting strategies, which directly specify limits on total mass emissions, emission-related parameters (e.g., emission rates per unit of production, product content limits), or levels of emissions reductions relative to a program baseline that affected sources are required to meet, while providing flexibility to sources to reduce the cost of meeting program requirements.
(ii) Market-response strategies, which create one or more incentives for affected sources to reduce emissions, without directly specifying limits on emissions or emission-related parameters that individual sources or even all sources in the aggregate are required to meet.
(iii) Directionally-sound strategies, for which adequate procedures to quantify emissions reductions are not defined.
(b)
(i) The extent to which the program is mandatory or voluntary for the affected sources.
(ii) Provisions, if any, by which sources that are not required to be in the program may voluntarily enter the program.
(iii) Provisions, if any, by which sources covered by the program may voluntarily leave the program.
(2) Any opt-in or opt-out provisions in paragraph (b)(1) of this section shall be designed to provide mechanisms by which such program changes are reflected in an area's attainment and RFP demonstrations, thus ensuring that there will not be an increase in the emissions inventory for the area caused by voluntary entry or exit from the program.
(3) The program scope shall be defined so as not to interfere with any other Federal requirements which apply to the affected sources.
(c)
(1) For EIP's submitted in conjunction with, or subsequent to, the submission of any areawide progress plan due at the time of EIP submission (e.g., the 15 percent RFP plan and/or subsequent 3 percent plans) or an attainment demonstration, a State may exercise flexibility in setting a program baseline provided the program baseline is consistent with and reflected in all relevant progress plans or attainment demonstration. A flexible program baseline may be based on the lower of actual, allowable, or some other intermediate or lower level of emissions. For any EIP submitted prior to the submittal of an attainment demonstration, the State shall include the following with its EIP submittal:
(i) A commitment that its subsequent attainment demonstration and all future progress plans, if applicable, will be consistent with the EIP baseline.
(ii) A discussion of how the baseline will be integrated into the subsequent attainment demonstration, taking into account the potential that credit issued prior to the attainment demonstration may no longer be surplus relative to the attainment demonstration.
(2) Except as provided for in paragraph (c)(4) of this section, for EIP's submitted during a time period when any progress plans are required but not yet submitted (e.g., the 15 percent RFP plan and/or the subsequent 3 percent plans), the program baseline shall be based on the lower-of-actual-or-allowable emissions. In such cases, actual emissions shall be taken from the most appropriate inventory, such as the 1990 actual emission inventory (due for submission in November 1992), and allowable emissions are the lower of SIP-allowable emissions or the level of emissions consistent with source compliance with all Federal requirements related to attainment and maintenance of the NAAQS.
(3) For EIP's that are designed to implement new and/or previously existing RACT requirements through emissions trading and are submitted in conjunction with, or subsequent to, the submission of an associated RACT rule, a State may exercise flexibility in setting a program baseline provided the program baseline is consistent with and reflected in the associated RACT rule, and any applicable progress plans and attainment demonstrations.
(4) For EIP's that are designed to implement new and/or previously existing RACT requirements through emissions trading and are submitted prior to the submission of a required RFP plan or attainment demonstration, States also have flexibility in determining the program baseline, provided the following conditions are met.
(i) For EIP's that implement new RACT requirements for previously unregulated source categories through emissions trading, the new RACT requirements must reflect, to the extent practicable, increased emissions reductions beyond those that would be achieved through a traditional RACT program.
(ii) For EIP's that impose new RACT requirements on previously unregulated sources in a previously regulated source category (e.g., RACT “catch-up” programs), the new incentive-based RACT rule shall, in the aggregate, yield reductions in actual emissions at least equivalent to that which would result from source-by-source compliance with the existing RACT limit for that source category.
(5) A program baseline for individual sources shall, as appropriate, be contained or incorporated by reference in federally-enforceable operating permits or a federally-enforceable SIP.
(6) An initial baseline for TCM's shall be calculated by establishing the preexisting conditions in the areas of interest. This may include establishing to what extent TCM's have already been implemented, what average vehicle occupancy (AVO) levels have been achieved during peak and off-peak periods, what types of trips occur in the region, and what mode choices have been made in making these trips. In addition, the extent to which travel options are currently available within the region of interest shall be determined. These travel options may include, but are not limited to, the degree of dispersion of transit services, the current ridership rates, and the availability and usage of parking facilities.
(7) Information used in setting a program baseline shall be of sufficient quality to provide for at least as high a degree of accountability as currently exists for traditional control requirements for the categories of sources affected by the program.
(d)
(1) Specification of quantification methods. This element shall specify the approach or the combination or range of approaches that are acceptable for each source category affected by the program. Acceptable approaches may include, but are not limited to:
(i) Test methods for the direct measurement of emissions, either continuously or periodically.
(ii) Calculation equations which are a function of process or control system parameters, ambient conditions, activity levels, and/or throughput or production rates.
(iii) Mass balance calculations which are a function of inventory, usage, and/or disposal records.
(iv) EPA-approved emission factors, where appropriate and adequate.
(v) Any combination of these approaches.
(2) Specification of averaging times.
(i) The averaging time for any specified mass emissions caps or emission rate limits shall be consistent with: attaining and maintaining all applicable
(ii) If the averaging time for any specified VOC or NO
(3) Accounting for shutdowns and production curtailments. This accounting shall include provisions which ensure that:
(i) Emissions reductions associated with shutdowns and production curtailments are not double-counted in attainment or RFP demonstrations.
(ii) Any resultant “shifting demand” which increases emissions from other sources is accounted for in such demonstrations.
(4) Accounting for batch, seasonal, and cyclical operations. This accounting shall include provisions which ensure that the approaches used to account for such variable operations are consistent with attainment and RFP plans.
(5) Accounting for travel mode choice options, as appropriate, for TCM's. This accounting shall consider the factors or attributes of the different forms of travel modes (e.g., bus, ridesharing) which determine which type of travel an individual will choose. Such factors include, but are not limited to, time, cost, reliability, and convenience of the mode.
(e)
(1) Emission limits.
(i) For programs that impose limits on total mass emissions, emission rates, or other emission-related parameter(s), there must be an appropriate tracking system so that a facility's limits are readily ascertainable at all times.
(ii) For emission-limiting EIP's that authorize RACT sources to meet their RACT requirements through RACT/non-RACT trading, such trading shall result in an exceptional environmental benefit. Demonstration of an exceptional environmental benefit shall require either the use of the statutory offset ratios for nonattainment areas as the determinant of the amount of emissions reductions that would be required from non-RACT sources generating credits for RACT sources or, alternatively, a trading ratio of 1.1 to 1, at a minimum, may be authorized, provided exceptional environmental benefits are otherwise demonstrated.
(2) Monitoring, recordkeeping, and reporting requirements.
(i) An EIP (or the SIP as a whole) must contain test methods and, where necessary, emission quantification methodologies, appropriate to the emission limits established in the SIP. EIP sources must be subject to clearly specified MRR requirements appropriate to the test methods and any applicable quantification methodologies, and consistent with the EPA's title V rules, where applicable. Such MRR requirements shall provide sufficiently reliable and timely information to determine compliance with emission limits and other applicable strategy-specific requirements, and to provide for State and Federal enforceability of such limits and requirements. Methods for MRR may include, but are not limited to:
(A) The continuous monitoring of mass emissions, emission rates, or process or control parameters.
(B) In situ or portable measurement devices to verify control system operating conditions.
(C) Periodic measurement of mass emissions or emission rates using reference test methods.
(D) Operation and maintenance procedures and/or other work practices designed to prevent, identify, or remedy noncomplying conditions.
(E) Manual or automated recordkeeping of material usage, inventories, throughput, production, or levels of required activities.
(F) Any combination of these methods. EIP's shall require that responsible parties at each facility in the EIP program certify reported information.
(ii) Procedures for determining required data, including the emissions contribution from affected sources, for periods for which required data monitoring is not performed, data are otherwise missing, or data have been demonstrated to have been inaccurately determined.
(3) Any other applicable strategy-specific requirements.
(f)
(i) For emission-limiting programs, the projected results shall be consistent with the reductions in mass emissions or emissions-related parameters specified in the program design.
(ii) For market-response programs, the projected results shall be based on market analyses relating levels of targeted emissions and/or emission-related activities to program design parameters.
(iii) For directionally-sound programs, the projected results may be descriptive and shall be consistent with the area's attainment demonstration or maintenance plan.
(2) Quantitative projected results shall be adjusted through the use of two uncertainty factors, as appropriate, to reflect uncertainties inherent in both the extent to which sources will comply with program requirements and the overall program design.
(i) Uncertainty resulting from incomplete compliance shall be addressed through the use of a rule compliance factor.
(ii) Programmatic uncertainty shall be addressed through the use of a program uncertainty factor. Any presumptive norms set by the EPA shall be used unless an adequate justification for an alternative factor is included in supporting information to be supplied with the SIP submittal. In the absence of any EPA-specified presumptive norms, the State shall provide an adequate justification for the selected factors as part of the supporting information to be supplied with the SIP submittal.
(3) Unless otherwise provided in program-specific guidance issued by the EPA, EIP's for which SIP credit is taken shall include audit procedures to evaluate program implementation and track program results in terms of both actual emissions reductions, and, to the extent practicable, cost savings relative to traditional regulatory program requirements realized during program implementation. Such audits shall be conducted at specified time intervals, not to exceed three years. The State shall provide timely post-audit reports to the EPA.
(i) For emission-limiting EIP's, the State shall commit to ensure the timely implementation of programmatic revisions or other measures which the State, in response to the audit, deems necessary for the successful operation of the program in the context of overall RFP and attainment requirements.
(ii) For market-response EIP's, reconciliation procedures that identify a range of appropriate actions or revisions to program requirements that will make up for any shortfall between credited results (i.e., projected results, as adjusted by the two uncertainty factors described above) and actual results obtained during program implementation shall be submitted together with the program audit provisions. Such measures must be federally enforceable, as appropriate, and automatically executing to the extent necessary to
(g)
(h)
(1) States shall furnish adequate documentation of existing legal authority and demonstrated administrative capacity to implement and enforce the provisions of the EIP.
(2) For programs which require private and/or public entities to establish emission-related economic incentives (e.g., programs requiring employers to exempt carpoolers/multiple occupancy vehicles from paying for parking), States shall furnish adequate documentation of State authority and administrative capacity to implement and enforce the underlying program.
(i)
(1) Emission limit violations. (i) Programs imposing limits on mass emissions or emission rates that provide for extended averaging times and/or compliance on a multisource basis shall include procedures for determining the number of violations, the number of days of violation, and sources in violation, for statutory maximum penalty purposes, when the limits are exceeded. The State shall demonstrate that such procedures shall not lessen the incentive for source compliance as compared to a program applied on a source-by-source, daily basis.
(ii) Programs shall require plans for remedying noncompliance at any facility that exceeds a multisource emissions limit for a given averaging period. These plans shall be enforceable both federally and by the State.
(2) Violations of MRR requirements. The MRR requirements shall apply on a daily basis, as appropriate, and violations thereof shall be subject to State enforcement sanctions and to the Federal penalty of up to $25,000 for each day a violation occurs or continues. In addition, where the requisite scienter conditions are met, violations of such requirements shall be subject to the Act's criminal penalty sanctions of section 113(c)(2), which provides for fines and imprisonment of up to 2 years.
Any revenues generated from statutory EIP's shall be used by the State for any of the following:
(a) Providing incentives for achieving emissions reductions.
(b) Providing assistance for the development of innovative technologies for the control of O
(c) Funding the administrative costs of State programs under this Act. Not more than 50 percent of such revenues may be used for this purpose. The use of any revenues generated from discretionary EIP's shall not be constrained by the provisions of this part.
(a) No department, agency or instrumentality of the Federal Government shall engage in, support in any way or provide financial assistance for, license or permit, or approve any activity which does not conform to an applicable implementation plan.
(b) A Federal agency must make a determination that a Federal action conforms to the applicable implementation plan in accordance with the requirements of this subpart before the action is taken.
(c) Paragraph (b) of this section does not include Federal actions where either:
(1) A National Environmental Policy Act (NEPA) analysis was completed as evidenced by a final environmental assessment (EA), environmental impact statement (EIS), or finding of no significant impact (FONSI) that was prepared prior to January 31, 1994;
(2)(i) Prior to January 31, 1994, an EA was commenced or a contract was awarded to develop the specific environmental analysis;
(ii) Sufficient environmental analysis is completed by March 15, 1994 so that the Federal agency may determine that the Federal action is in conformity with the specific requirements and the purposes of the applicable SIP pursuant to the agency's affirmative obligation under section 176(c) of the Clean Air Act (Act); and
(iii) A written determination of conformity under section 176(c) of the Act has been made by the Federal agency responsible for the Federal action by March 15, 1994.
(d) Notwithstanding any provision of this subpart, a determination that an action is in conformance with the applicable implementation plan does not exempt the action from any other requirements of the applicable implementation plan, the NEPA, or the Act.
(a) Each State must submit to the Environmental Protection Agency (EPA) a revision to its applicable implementation plan which contains criteria and procedures for assessing the conformity of Federal actions to the applicable implementation plan, consistent with this subpart. The State must submit the conformity provisions within 12 months after November 30, 1993 or within 12 months of an area's designation to nonattainment, whichever date is later.
(b) The Federal conformity rules under this subpart and 40 CFR part 93, in addition to any existing applicable State requirements, establish the conformity criteria and procedures necessary to meet the Act requirements until such time as the required conformity SIP revision is approved by EPA. A State's conformity provisions must contain criteria and procedures that are no less stringent than the requirements described in this subpart. A State may establish more stringent conformity criteria and procedures only if they apply equally to non-Federal as well as Federal entities. Following EPA approval of the State conformity provisions (or a portion thereof) in a revision to the applicable SIP, the approved (or approved portion of the) State criteria and procedures would govern conformity determinations and the Federal conformity regulations contained in 40 CFR part 93 would apply only for the portion, if any, of the State's conformity provisions that is not approved by EPA. In addition, any previously applicable SIP requirements relating to conformity remain enforceable until the State revises its SIP to specifically remove them from the SIP and that revision is approved by EPA.
Terms used but not defined in this part shall have the meaning given them by the Act and EPA's regulations, (40 CFR chapter I), in that order of priority.
(1) Causes a new violation of a national ambient air quality standard (NAAQS) at a location in a nonattainment or maintenance area which would otherwise not be in violation of the standard during the future period in question if the Federal action were not taken; or
(2) Contributes, in conjunction with other reasonably foreseeable actions, to a new violation of a NAAQS at a location in a nonattainment or maintenance area in a manner that would increase the frequency or severity of the new violation.
(1) Are caused by the Federal action, but may occur later in time and/or may be farther removed in distance from the action itself but are still reasonably foreseeable; and
(2) The Federal agency can practicably control and will maintain control over due to a continuing program responsibility of the Federal agency.
(1) For ozone, nitrogen oxides (NO
(2) For PM-10, those pollutants described in the PM-10 nonattainment area applicable SIP as significant contributors to the PM-10 levels.
(a) Conformity determinations for Federal actions related to transportation plans, programs, and projects developed, funded, or approved under title 23 U.S.C. or the Federal Transit Act (49 U.S.C. 1601
(b) For Federal actions not covered by paragraph (a) of this section, a conformity determination is required for
(1) For purposes of paragraph (b) of this section, the following rates apply in nonattainment areas (NAAs):
(2) For purposes of paragraph (b) of this section, the following rates apply in maintenance areas:
(c) The requirements of this subpart shall not apply to:
(1) Actions where the total of direct and indirect emissions are below the emissions levels specified in paragraph (b) of this section.
(2) The following actions which would result in no emissions increase or an increase in emissions that is clearly de minimis:
(i) Judicial and legislative proceedings.
(ii) Continuing and recurring activities such as permit renewals where activities conducted will be similar in scope and operation to activities currently being conducted.
(iii) Rulemaking and policy development and issuance.
(iv) Routine maintenance and repair activities, including repair and maintenance of administrative sites, roads, trails, and facilities.
(v) Civil and criminal enforcement activities, such as investigations, audits, inspections, examinations, prosecutions, and the training of law enforcement personnel.
(vi) Administrative actions such as personnel actions, organizational changes, debt management or collection, cash management, internal agency audits, program budget proposals, and matters relating to the administration and collection of taxes, duties and fees.
(vii) The routine, recurring transportation of materiel and personnel.
(viii) Routine movement of mobile assets, such as ships and aircraft, in home port reassignments and stations (when no new support facilities or personnel are required) to perform as operational groups and/or for repair or overhaul.
(ix) Maintenance dredging and debris disposal where no new depths are required, applicable permits are secured, and disposal will be at an approved disposal site.
(x) Actions, such as the following, with respect to existing structures, properties, facilities and lands where future activities conducted will be similar in scope and operation to activities currently being conducted at the existing structures, properties, facilities, and lands; for example, relocation of personnel, disposition of federally-owned existing structures, properties, facilities, and lands, rent subsidies, operation and maintenance cost subsidies, the exercise of receivership or conservatorship authority, assistance in purchasing structures, and the production of coins and currency.
(xi) The granting of leases, licenses such as for exports and trade, permits, and easements where activities conducted will be similar in scope and operation to activities currently being conducted.
(xii) Planning, studies, and provision of technical assistance.
(xiii) Routine operation of facilities, mobile assets and equipment.
(xiv) Transfers of ownership, interests, and titles in land, facilities, and
(xv) The designation of empowerment zones, enterprise communities, or viticultural areas.
(xvi) Actions by any of the Federal banking agencies or the Federal Reserve Banks, including actions regarding charters, applications, notices, licenses, the supervision or examination of depository institutions or depository institution holding companies, access to the discount window, or the provision of financial services to banking organizations or to any department, agency or instrumentality of the United States.
(xvii) Actions by the Board of Governors of the Federal Reserve System or any Federal Reserve Bank to effect monetary or exchange rate policy.
(xviii) Actions that implement a foreign affairs function of the United States.
(xix) Actions (or portions thereof) associated with transfers of land, facilities, title, and real properties through an enforceable contract or lease agreement where the delivery of the deed is required to occur promptly after a specific, reasonable condition is met, such as promptly after the land is certified as meeting the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), and where the Federal agency does not retain continuing authority to control emissions associated with the lands, facilities, title, or real properties.
(xx) Transfers of real property, including land, facilities, and related personal property from a Federal entity to another Federal entity and assignments of real property, including land, facilities, and related personal property from a Federal entity to another Federal entity for subsequent deeding to eligible applicants.
(xxi) Actions by the Department of the Treasury to effect fiscal policy and to exercise the borrowing authority of the United States.
(3) The following actions where the emissions are not reasonably foreseeable:
(i) Initial Outer Continental Shelf lease sales which are made on a broad scale and are followed by exploration and development plans on a project level.
(ii) Electric power marketing activities that involve the acquisition, sale and transmission of electric energy.
(4) Actions which implement a decision to conduct or carry out a conforming program such as prescribed burning actions which are consistent with a conforming land management plan.
(d) Notwithstanding the other requirements of this subpart, a conformity determination is not required for the following Federal actions (or portion thereof):
(1) The portion of an action that includes major new or modified stationary sources that require a permit under the new source review (NSR) program (section 173 of the Act) or the prevention of significant deterioration (PSD) program (title I, part C of the Act).
(2) Actions in response to emergencies or natural disasters such as hurricanes, earthquakes, etc., which are commenced on the order of hours or days after the emergency or disaster and, if applicable, which meet the requirements of paragraph (e) of this section.
(3) Research, investigations, studies, demonstrations, or training (other than those exempted under paragraph (c)(2) of this section), where no environmental detriment is incurred and/or, the particular action furthers air quality research, as determined by the State agency primarily responsible for the applicable SIP.
(4) Alteration and additions of existing structures as specifically required by new or existing applicable environmental legislation or environmental regulations (e.g., hush houses for aircraft engines and scrubbers for air emissions).
(5) Direct emissions from remedial and removal actions carried out under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and associated regulations to the extent such emissions either comply with the substantive requirements of the PSD/NSR permitting program or are exempted from other environmental regulation under the
(e) Federal actions which are part of a continuing response to an emergency or disaster under paragraph (d)(2) of this section and which are to be taken more than 6 months after the commencement of the response to the emergency or disaster under paragraph (d)(2) of this section are exempt from the requirements of this subpart only if:
(1) The Federal agency taking the actions makes a written determination that, for a specified period not to exceed an additional 6 months, it is impractical to prepare the conformity analyses which would otherwise be required and the actions cannot be delayed due to overriding concerns for public health and welfare, national security interests and foreign policy commitments; or
(2) For actions which are to be taken after those actions covered by paragraph (e)(1) of this section, the Federal agency makes a new determination as provided in paragraph (e)(1) of this section.
(f) Notwithstanding other requirements of this subpart, actions specified by individual Federal agencies that have met the criteria set forth in either paragraph (g)(1) or (g)(2) of this section and the procedures set forth in paragraph (h) of this section are presumed to conform, except as provided in paragraph (j) of this section.
(g) The Federal agency must meet the criteria for establishing activities that are presumed to conform by fulfilling the requirements set forth in either paragraph (g)(1) or (g)(2) of this section:
(1) The Federal agency must clearly demonstrate using methods consistent with this subpart that the total of direct and indirect emissions from the type of activities which would be presumed to conform would not:
(i) Cause or contribute to any new violation of any standard in any area;
(ii) Interfere with provisions in the applicable SIP for maintenance of any standard;
(iii) Increase the frequency or severity of any existing violation of any standard in any area; or
(iv) Delay timely attainment of any standard or any required interim emission reductions or other milestones in any area including, where applicable, emission levels specified in the applicable SIP for purposes of:
(A) A demonstration of reasonable further progress;
(B) A demonstration of attainment; or
(C) A maintenance plan; or
(2) The Federal agency must provide documentation that the total of direct and indirect emissions from such future actions would be below the emission rates for a conformity determination that are established in paragraph (b) of this section, based, for example, on similar actions taken over recent years.
(h) In addition to meeting the criteria for establishing exemptions set forth in paragraphs (g)(1) or (g)(2) of this section, the following procedures must also be complied with to presume that activities will conform:
(1) The Federal agency must identify through publication in the
(2) The Federal agency must notify the appropriate EPA Regional Office(s), State and local air quality agencies and, where applicable, the agency designated under section 174 of the Act and the MPO and provide at least 30 days for the public to comment on the list of proposed activities presumed to conform;
(3) The Federal agency must document its response to all the comments received and make the comments, response, and final list of activities available to the public upon request; and
(4) The Federal agency must publish the final list of such activities in the
(i) Notwithstanding the other requirements of this subpart, when the total of direct and indirect emissions of any pollutant from a Federal action does not equal or exceed the rates specified in paragraph (b) of this section, but represents 10 percent or more of a nonattainment or maintenance area's total emissions of that pollutant, the
(j) Where an action otherwise presumed to conform under paragraph (f) of this section is a regionally significant action or does not in fact meet one of the criteria in paragraph (g)(1) of this section, that action shall not be presumed to conform and the requirements of § 51.850 and §§ 51.855 through 51.860 shall apply for the Federal action.
(k) The provisions of this subpart shall apply in all nonattainment and maintenance areas.
Any Federal department, agency, or instrumentality of the Federal Government taking an action subject to this subpart must make its own conformity determination consistent with the requirements of this subpart. In making its conformity determination, a Federal agency must consider comments from any interested parties. Where multiple Federal agencies have jurisdiction for various aspects of a project, a Federal agency may choose to adopt the analysis of another Federal agency or develop its own analysis in order to make its conformity determination.
(a) A Federal agency making a conformity determination under § 51.858 must provide to the appropriate EPA Regional Office(s), State and local air quality agencies and, where applicable, affected Federal land managers, the agency designated under section 174 of the Act and the MPO a 30 day notice which describes the proposed action and the Federal agency's draft conformity determination on the action.
(b) A Federal agency must notify the appropriate EPA Regional Office(s), State and local air quality agencies and, where applicable, affected Federal land managers, the agency designated under section 174 of the Clean Air Act and the MPO within 30 days after making a final conformity determination under § 51.858.
(a) Upon request by any person regarding a specific Federal action, a Federal agency must make available for review its draft conformity determination under § 51.858 with supporting materials which describe the analytical methods and conclusions relied upon in making the applicability analysis and draft conformity determination.
(b) A Federal agency must make public its draft conformity determination under § 51.858 by placing a notice by prominent advertisement in a daily newspaper of general circulation in the area affected by the action and by providing 30 days for written public comment prior to taking any formal action on the draft determination. This comment period may be concurrent with any other public involvement, such as occurs in the NEPA process.
(c) A Federal agency must document its response to all the comments received on its draft conformity determination under § 51.858 and make the comments and responses available, upon request by any person regarding a specific Federal action, within 30 days of the final conformity determination.
(d) A Federal agency must make public its final conformity determination under § 51.858 for a Federal action by placing a notice by prominent advertisement in a daily newspaper of general circulation in the area affected by the action within 30 days of the final conformity determination.
(a) The conformity status of a Federal action automatically lapses 5 years from the date a final conformity determination is reported under § 51.855, unless the Federal action has been completed or a continuous program has been commenced to implement that Federal action within a reasonable time.
(b) Ongoing Federal activities at a given site showing continuous progress are not new actions and do not require periodic redeterminations so long as such activities are within the scope of the final conformity determination reported under § 51.855.
(c) If, after the conformity determination is made, the Federal action is changed so that there is an increase in the total of direct and indirect emissions above the levels in § 51.853(b), a new conformity determination is required.
(a) An action required under § 51.853 to have a conformity determination for a specific pollutant, will be determined to conform to the applicable SIP if, for each pollutant that exceeds the rates in § 51.853(b), or otherwise requires a conformity determination due to the total of direct and indirect emissions from the action, the action meets the requirements of paragraph (c) of this section, and meets any of the following requirements:
(1) For any criteria pollutant, the total of direct and indirect emissions from the action are specifically identified and accounted for in the applicable SIP's attainment or maintenance demonstration;
(2) For ozone or nitrogen dioxide, the total of direct and indirect emissions from the action are fully offset within the same nonattainment or maintenance area through a revision to the applicable SIP or a similarly enforceable measure that effects emission reductions so that there is no net increase in emissions of that pollutant;
(3) For any criteria pollutant, except ozone and nitrogen dioxide, the total of direct and indirect emissions from the action meet the requirements:
(i) Specified in paragraph (b) of this section, based on areawide air quality modeling analysis and local air quality modeling analysis; or
(ii) Meet the requirements of paragraph (a)(5) of this section and, for local air quality modeling analysis, the requirement of paragraph (b) of this section;
(4) For CO or PM-10—
(i) Where the State agency primarily responsible for the applicable SIP determines that an areawide air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meet the requirements specified in paragraph (b) of this section, based on local air quality modeling analysis; or
(ii) Where the State agency primarily responsible for the applicable SIP determines that an areawide air quality modeling analysis is appropriate and that a local air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meet the requirements specified in paragraph (b) of this section, based on areawide modeling, or meet the requirements of paragraph (a)(5) of this section; or
(5) For ozone or nitrogen dioxide, and for purposes of paragraphs (a)(3)(ii) and (a)(4)(ii) of this section, each portion of the action or the action as a whole meets any of the following requirements:
(i) Where EPA has approved a revision to an area's attainment or maintenance demonstration after 1990 and the State makes a determination as provided in paragraph (a)(5)(i)(A) of this section or where the State makes a commitment as provided in paragraph (a)(5)(i)(B) of this section:
(A) The total of direct and indirect emissions from the action (or portion thereof) is determined and documented by the State agency primarily responsible for the applicable SIP to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would not exceed the emissions budgets specified in the applicable SIP;
(B) The total of direct and indirect emissions from the action (or portion thereof) is determined by the State agency responsible for the applicable SIP to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would exceed an emissions budget specified in the applicable SIP and the State Governor or the Governor's designee for SIP actions makes a written commitment to EPA which includes the following:
(
(
(
(
(
(C) Where a Federal agency made a conformity determination based on a State commitment under paragraph (a)(5)(i)(B) of this section, such a State commitment is automatically deemed a call for a SIP revision by EPA under section 110(k)(5) of the Act, effective on the date of the Federal conformity determination and requiring response within 18 months or any shorter time within which the State commits to revise the applicable SIP;
(ii) The action (or portion thereof), as determined by the MPO, is specifically included in a current transportation plan and transportation improvement program which have been found to conform to the applicable SIP under 40 CFR part 51, subpart T, or 40 CFR part 93, subpart A;
(iii) The action (or portion thereof) fully offsets its emissions within the same nonattainment or maintenance area through a revision to the applicable SIP or an equally enforceable measure that effects emission reductions equal to or greater than the total of direct and indirect emissions from the action so that there is no net increase in emissions of that pollutant;
(iv) Where EPA has not approved a revision to the relevant SIP attainment or maintenance demonstration since 1990, the total of direct and indirect emissions from the action for the future years (described in § 51.859(d)) do not increase emissions with respect to the baseline emissions:
(A) The baseline emissions reflect the historical activity levels that occurred in the geographic area affected by the proposed Federal action during:
(
(
(
(B) The baseline emissions are the total of direct and indirect emissions calculated for the future years (described in § 51.859(d)) using the historic activity levels (described in paragraph (a)(5)(iv)(A) of this section) and appropriate emission factors for the future years; or
(v) Where the action involves regional water and/or wastewater projects, such projects are sized to meet only the needs of population projections that are in the applicable SIP.
(b) The areawide and/or local air quality modeling analyses must:
(1) Meet the requirements in § 51.859; and
(2) Show that the action does not:
(i) Cause or contribute to any new violation of any standard in any area; or
(ii) Increase the frequency or severity of any existing violation of any standard in any area.
(c) Notwithstanding any other requirements of this section, an action subject to this subpart may not be determined to conform to the applicable SIP unless the total of direct and indirect emissions from the action is in compliance or consistent with all relevant requirements and milestones contained in the applicable SIP, such as elements identified as part of the reasonable further progress schedules, assumptions specified in the attainment or maintenance demonstration, prohibitions, numerical emission limits, and work practice requirements.
(d) Any analyses required under this section must be completed, and any mitigation requirements necessary for a finding of conformity must be identified before the determination of conformity is made.
(a) The analyses required under this subpart must be based on the latest planning assumptions.
(1) All planning assumptions must be derived from the estimates of population, employment, travel, and congestion most recently approved by the MPO, or other agency authorized to make such estimates, where available.
(2) Any revisions to these estimates used as part of the conformity determination, including projected shifts in geographic location or level of population, employment, travel, and congestion, must be approved by the MPO or other agency authorized to make such estimates for the urban area.
(b) The analyses required under this subpart must be based on the latest and most accurate emission estimation techniques available as described below, unless such techniques are inappropriate. If such techniques are inappropriate and written approval of the EPA Regional Administrator is obtained for any modification or substitution, they may be modified or another technique substituted on a case-by-case basis or, where appropriate, on a generic basis for a specific Federal agency program.
(1) For motor vehicle emissions, the most current version of the motor vehicle emissions model specified by EPA and available for use in the preparation or revision of SIPs in that State must be used for the conformity analysis as specified in paragraphs (b)(1) (i) and (ii) of this section:
(i) The EPA must publish in the
(ii) A grace period of three months shall apply during which the motor vehicle emissions model previously specified by EPA as the most current version may be used. Conformity analyses for which the analysis was begun during the grace period or no more than 3 years before the
(2) For non-motor vehicle sources, including stationary and area source emissions, the latest emission factors specified by EPA in the “Compilation of Air Pollutant Emission Factors (AP-42)”
(c) The air quality modeling analyses required under this subpart must be based on the applicable air quality models, data bases, and other requirements specified in the most recent version of the “Guideline on Air Quality Models (Revised)” (1986), including supplements (EPA publication no. 450/2-78-027R)
(1) The guideline techniques are inappropriate, in which case the model may be modified or another model substituted on a case-by-case basis or, where appropriate, on a generic basis for a specific Federal agency program; and
(2) Written approval of the EPA Regional Administrator is obtained for any modification or substitution.
(d) The analyses required under this subpart, except § 51.858(a)(1), must be based on the total of direct and indirect emissions from the action and must reflect emission scenarios that are expected to occur under each of the following cases:
(1) The Act mandated attainment year or, if applicable, the farthest year for which emissions are projected in the maintenance plan;
(2) The year during which the total of direct and indirect emissions from the action is expected to be the greatest on an annual basis; and
(3) any year for which the applicable SIP specifies an emissions budget.
(a) Any measures that are intended to mitigate air quality impacts must be identified and the process for implementation and enforcement of such measures must be described, including
(b) Prior to determining that a Federal action is in conformity, the Federal agency making the conformity determination must obtain written commitments from the appropriate persons or agencies to implement any mitigation measures which are identified as conditions for making conformity determinations.
(c) Persons or agencies voluntarily committing to mitigation measures to facilitate positive conformity determinations must comply with the obligations of such commitments.
(d) In instances where the Federal agency is licensing, permitting or otherwise approving the action of another governmental or private entity, approval by the Federal agency must be conditioned on the other entity meeting the mitigation measures set forth in the conformity determination.
(e) When necessary because of changed circumstances, mitigation measures may be modified so long as the new mitigation measures continue to support the conformity determination. Any proposed change in the mitigation measures is subject to the reporting requirements of § 51.856 and the public participation requirements of § 51.857.
(f) The implementation plan revision required in § 51.851 shall provide that written commitments to mitigation measures must be obtained prior to a positive conformity determination and that such commitments must be fulfilled.
(g) After a State revises its SIP to adopt its general conformity rules and EPA approves that SIP revision, any agreements, including mitigation measures, necessary for a conformity determination will be both State and federally enforceable. Enforceability through the applicable SIP will apply to all persons who agree to mitigate direct and indirect emissions associated with a Federal action for a conformity determination.
The example regulations presented herein reflect generally recognized ways of preventing air pollution from reaching levels that would cause imminent and substantial endangerment to the health of persons. States are required under subpart H to have emergency episodes plans but they are not required to adopt the regulations presented herein.
1.0
1.1
(a)
(b)
In addition to the levels listed for the above pollutants, meterological conditions are such that pollutant concentrations can be expected to remain at the above levels for twelve (12) or more hours or increase, or in the case of ozone, the situation is likely to reoccur within the next 24-hours unless control actions are taken.
(c)
In addition to the levels listed for the above pollutants, meterological conditions are such that pollutant concentrations can be expected to remain at the above levels for twelve (12) or more hours or increase, or in the case of ozone, the situation is likely to reoccur within the next 24-hours unless control actions are taken.
(d)
In addition to the levels listed for the above pollutants, meterological conditions are such that pollutant concentrations can be expected to remain at the above levels for twelve (12) or more hours or increase, or in the case of ozone, the situation is likely to reoccur within the next 24-hours unless control actions are taken.
(e)
1.2
(b) Air Pollution Warning—When the Director declares an Air Pollution Warning, any person responsible for the operation of a source of air pollutants as set forth in Table II shall take all Air Pollution Warning actions as required for such source of air pollutants and shall put into effect the preplanned abatement strategy for an Air Pollution Warning.
(c) Air Pollution Emergency—When the Director declares an Air Pollution Emergency, any person responsible for the operation of a source of air pollutants as described in Table III shall take all Air Pollution Emergency actions as required for such source of air pollutants and shall put into effect the preplanned abatement strategy for an Air Pollution Emergency.
(d) When the Director determines that a specified criteria level has been reached at one or more monitoring sites solely because of emissions from a limited number of sources, he shall notify such source(s) that the preplanned abatement strategies of Tables I, II, and III or the standby plans are required, insofar as it applies to such source(s), and shall be put into effect until the criteria of the specified level are no longer met.
1.3
(b) Any person responsible for the operation of a source of air pollutants not set forth under section 1.3(a) shall, when requested by the Director in writing, prepare standby plans for reducing the emission of air pollutants during periods of an Air Pollution Alert, Air Pollution Warning, and Air Pollution Emergency. Standby plans shall be designed to reduce or eliminate emissions of air pollutants in accordance with the objectives set forth in Tables I-III.
(c) Standby plans as required under section 1.3(a) and (b) shall be in writing and identify the sources of air pollutants, the approximate amount of reduction of pollutants and a brief description of the manner in which the reduction will be achieved during an Air Pollution Alert, Air Pollution Warning, and Air Pollution Emergency.
(d) During a condition of Air Pollution Alert, Air Pollution Warning, and Air Pollution Emergency, standby plans as required by this section shall be made available on the premises to any person authorized to enforce the provisions of applicable rules and regulations.
(e) Standby plans as required by this section shall be submitted to the Director upon request within thirty (30) days of the receipt of such request; such standby plans shall be subject to review and approval by the Director. If, in the opinion of the Director, a standby plan does not effectively carry out the objectives as set forth in Table I-III, the Director may disapprove it, state his reason for disapproval and order the preparation of an amended standby plan within the time period specified in the order.
1. There shall be no open burning by any persons of tree waste, vegetation, refuse, or debris in any form.
2. The use of incinerators for the disposal of any form of solid waste shall be limited to the hours between 12 noon and 4 p.m.
3. Persons operating fuel-burning equipment which required boiler lancing or soot blowing shall perform such operations only between the hours of 12 noon and 4 p.m.
4. Persons operating motor vehicles should eliminate all unnecessary operations.
Any person responsible for the operation of a source of air pollutants listed below shall take all required control actions for this Alert Level.
1. There shall be no open burning by any persons of tree waste, vegetation, refuse, or debris in any form.
2. The use of incinerators for the disposal of any form of solid waste or liquid waste shall be prohibited.
3. Persons operating fuel-burning equipment which requires boiler lancing or soot blowing shall perform such operations only between the hours of 12 noon and 4 p.m.
4. Persons operating motor vehicles must reduce operations by the use of car pools and increased use of public transportation and elimination of unnecessary operation.
Any person responsible for the operation of a source of air pollutants listed below shall take all required control actions for this Warning Level.
1. There shall be no open burning by any persons of tree waste, vegetation, refuse, or debris in any form.
2. The use of incinerators for the disposal of any form of solid or liquid waste shall be prohibited.
3. All places of employment described below shall immediately cease operations.
a. Mining and quarrying of nonmetallic minerals.
b. All construction work except that which must proceed to avoid emergent physical harm.
c. All manufacturing establishments except those required to have in force an air pollution emergency plan.
d. All wholesale trade establishments; i.e., places of business primarily engaged in selling merchandise to retailers, or industrial, commercial, institutional or professional users, or to other wholesalers, or acting as agents in buying merchandise for or selling merchandise to such persons or companies, except those engaged in the distribution of drugs, surgical supplies and food.
e. All offices of local, county and State government including authorities, joint meetings, and other public bodies excepting such agencies which are determined by the chief administrative officer of local, county, or State government, authorities, joint meetings and other public bodies to be vital for public safety and welfare and the enforcement of the provisions of this order.
f. All retail trade establishments except pharmacies, surgical supply distributors, and stores primarily engaged in the sale of food.
g. Banks, credit agencies other than banks, securities and commodities brokers, dealers, exchanges and services; offices of insurance carriers, agents and brokers, real estate offices.
h. Wholesale and retail laundries, laundry services and cleaning and dyeing establishments; photographic studios; beauty shops, barber shops, shoe repair shops.
i. Advertising offices; consumer credit reporting, adjustment and collection agencies; duplicating, addressing, blueprinting; photocopying, mailing, mailing list and stenographic services; equipment rental services, commercial testing laboratories.
j. Automobile repair, automobile services, garages.
k. Establishments rendering amusement and recreational services including motion picture theaters.
l. Elementary and secondary schools, colleges, universities, professional schools, junior colleges, vocational schools, and public and private libraries.
4. All commercial and manufacturing establishments not included in this order will institute such actions as will result in maximum reduction of air pollutants from their operation by ceasing, curtailing, or postponing operations which emit air pollutants to the extent possible without causing injury to persons or damage to equipment.
5. The use of motor vehicles is prohibited except in emergencies with the approval of local or State police.
Any person responsible for the operation of a source of air pollutants listed below shall take all required control actions for this Emergency Level.
Presented herein are recommended test methods for measuring air pollu-tant-emana-ting from an emission source. They are provided for States to use in their plans to meet the requirements of subpart K—Source Surveillance.
The State may also choose to adopt other methods to meet the requirements of subpart K of this part, subject to the normal plan review process.
The State may also meet the requirements of subpart K of this part by adopting, again subject to the normal plan review process, any of the relevant methods in appendix A to 40 CFR part 60.
1.1 Applicability. This method applies to the in-stack measurement of particulate matter (PM) emissions equal to or less than an aerodynamic diameter of nominally 10 μm (PM
1.2 Principle. A gas sample is isokinetically extracted from the source. An in-stack cyclone is used to separate PM greater than PM
Method 5 as cited in this method refers to the method in 40 CFR part 60, appendix A.
2.1 Sampling Train. A schematic of the exhaust of the exhaust gas recycle (EGR) train is shown in Figure 1 of this method.
2.1.1 Nozzle with Recycle Attachment. Stainless steel (316 or equivalent) with a sharp tapered leading edge, and recycle attachment welded directly on the side of the nozzle (see schematic in Figure 2 of this method). The angle of the taper shall be on the outside. Use only straight sampling nozzles. “Gooseneck” or other nozzle extensions designed to turn the sample gas flow 90°, as in Method 5 are not acceptable. Locate a thermocouple in the recycle attachment to measure the temperature of the recycle gas as shown in Figure 3 of this method. The recycle attachment shall be made of stainless steel and shall be connected to the probe and nozzle with stainless steel fittings. Two nozzle sizes, e.g., 0.125 and 0.160 in., should be available to allow isokinetic sampling to be conducted over a range of flow rates. Calibrate each nozzle as described in Method 5, Section 5.1.
2.1.2 PM
2.1.3 Filter Holder. 63mm, stainless steel. An Andersen filter, part number SE274, has been found to be acceptable for the in-stack filter.
Mention of trade names or specific products does not constitute endorsement by the Environmental Protection Agency.
2.1.4 Pitot Tube. Same as in Method 5, Section 2.1.3. Attach the pitot to the pitot lines with stainless steel fittings and to the cyclone in a configuration similar to that shown in Figure 3 of this method. The pitot lines shall be made of heat resistant material and attached to the probe with stainless steel fittings.
2.1.5 EGR Probe. Stainless steel, 15.9-mm (
2.1.6 Condenser. Same as in Method 5, Section 2.1.7.
2.1.7 Umbilical Connector. Flexible tubing with thermocouple and power leads of sufficient length to connect probe to meter and flow control console.
2.1.8 Vacuum Pump. Leak-tight, oil-less, noncontaminating, with an absolute filter, “HEPA” type, at the pump exit. A Gast Model 0522-V103 G18DX pump has been found to be satisfactory.
2.1.9 Meter and Flow Control Console. System consisting of a dry gas meter and calibrated orifice for measuring sample flow rate and capable of measuring volume to
2.1.10 Barometer. Same as in Method 5, Section 2.1.9.
2.1.11 Rubber Tubing. 6.35-mm (
2.2 Sample Recovery.
2.2.1 Nozzle, Cyclone, and Filter Holder Brushes. Nylon bristle brushes property sized and shaped for cleaning the nozzle, cyclone, filter holder, and probe or probe liner, with stainless steel wire shafts and handles.
2.2.2 Wash Bottles, Glass Sample Storage Containers, Petri Dishes, Graduated Cylinder and Balance, Plastic Storage Containers, and Funnels. Same as Method 5, Sections 2.2.2 through 2.2.6 and 2.2.8, respectively.
2.3 Analysis. Same as in Method 5, Section 2.3.
The reagents used in sampling, sample recovery, and analysis are the same as that specified in Method 5, Sections 3.1, 3.2, and 3.3, respectively.
4.1 Sampling. The complexity of this method is such that, in order to obtain reliable results, testers should be trained and experienced with the test procedures.
4.1.1 Pretest Preparation. Same as in Method 5, Section 4.1.1.
4.1.2 Preliminary Determinations. Same as Method 5, Section 4.1.2, except use the directions on nozzle size selection in this section.
4.1.2.1 The cyclone and filter holder must be in-stack or at stack temperature during sampling. The blockage effects of the EGR sampling assembly will be minimal if the cross-sectional area of the sampling assembly is 3 percent or less of the cross-sectional area of the duct and a pitot coefficient of 0.84 may be assigned to the pitot. If the cross-sectional area of the assembly is greater than 3 percent of the cross-sectional area of the duct, then either determine the pitot coefficient at sampling conditions or use a standard pitot with a known coefficient in a configuration with the EGR sampling assembly such that flow disturbances are minimized.
4.1.2.2 Construct a setup of pressure drops for various
4.1.2.3 The EGR setup program allows the tester to select the nozzle size based on anticipated average stack conditions and prints a setup sheet for field use. The amount of recycle through the nozzle should be between 10 and 80 percent. Inputs for the EGR setup program are stack temperature (minimum, maximum, and average), stack velocity (minimum, maximum, and average), atmospheric pressure, stack static pressure, meter box temperature, stack moisture, percent 0
4.1.2.4 A less rigorous calculation for the setup sheet can be done manually using the equations on the example worksheets in Figures 7, 8, and 9 of this method, or by a Hewlett-Packard HP41 calculator using the program provided in appendix D of the EGR operators manual, entitled
4.1.2.5 The pressure upstream of the LFE's is assumed to be constant at 0.6 in. Hg in the EGR setup calculations.
4.1.2.6 The setup sheet constructed using this procedure shall be similar to Figure 6 of this method. Inputs needed for the calculation are the same as for the setup computer except that stack velocities are not needed.
4.1.3 Preparation of Collection Train. Same as in Method 5, Section 4.1.3, except use the following directions to set up the train.
4.1.3.1 Assemble the EGR sampling device, and attach it to probe as shown in Figure 3 of this method. If stack temperatures exceed 260 °C (500 °F), then assemble the EGR cyclone without the O-ring and reduce the vacuum requirement to 130 mm Hg (5.0 in. Hg) in the leak-check procedure in Section 4.1.4.3.2 of this method.
4.1.3.2 Connect the proble directly to the filter holder and condenser as in Method 5. Connect the condenser and probe to the meter and flow control console with the umbilical connector. Plug in the pump and attach pump lines to the meter and flow control console.
4.1.4 Leak-Check Procedure. The leak-check for the EGR Method consists of two parts: the sample-side and the recycle-side. The sample-side leak-check is required at the beginning of the run with the cyclone attached, and after the run with the cyclone removed. The cyclone is removed before the post-test leak-check to prevent any disturbance of the collected sample prior to analysis. The recycle-side leak-check tests the leak tight integrity of the recycle components and is required prior to the first test run and after each shipment.
4.1.4.1 Pretest Leak-Check. A pretest leak-check of the entire sample-side, including the cyclone and nozzle, is required. Use the leak-check procedure in Section 4.1.4.3 of this method to conduct a pretest leak-check.
4.1.4.2 Leak-Checks During Sample Run. Same as in Method 5, Section 4.1.4.1.
4.1.4.3 Post-Test Leak-Check. A leak-check is required at the conclusion of each sampling run. Remove the cyclone before the leak-check to prevent the vacuum created by the cooling of the probe from disturbing the collected sample and use the following procedure to conduct a post-test leak-check.
4.1.4.3.1 The sample-side leak-check is performed as follows: After removing the cyclone, seal the probe with a leak-tight stopper. Before starting pump, close the coarse total valve and both recycle valves, and open completely the sample back pressure valve and the fine total valve. After turning the
A lower vacuum may be used, provided that it is not exceeded during the test.
4.1.4.3.2 Leak rates in excess of 0.00057 m
4.1.4.3.3 To complete the leak-check, slowly remove the stopper from the nozzle until the vacuum is near zero, then immediately turn off the pump. This procedure sequence prevents a pressure surge in the manometer fluid and rupture of the filter.
4.1.4.3.4 The recycle-side leak-check is performed as follows: Close the coarse and fine total valves and sample back pressure valve. Plug the sample inlet at the meter box. Turn on the power and the pump, close the recycle valves, and open the total flow valves. Adjust the total flow fine adjust valve until a vacuum of 25 inches of mercury is achieved. If the desired vacuum is exceeded, either leak-check at this higher vacuum, or end the leak-check and start over. Minimum acceptable leak rates are the same as for the sample-side. If the leak rate is too high, void the sampling run.
4.1.5 EGR Train Operation. Same as in Method 5, Section 4.1.5, except omit references to nomographs and recommendations about changing the filter assembly during a run.
4.1.5.1 Record the data required on a data sheet such as the one shown in Figure 10 of this method. Make periodic checks of the manometer level and zero to ensure correct
4.1.5.2 The procedure for using the example EGR setup sheet is as follows: Obtain a stack velocity reading from the pitot manometer (
4.1.5.3 The top three numbers are differential pressures (in. H
4.1.5.4 For startup of the EGR sample train, the following procedure is recommended. Preheat the cyclone in the stack for 30 minutes. Close both the sample and recycle coarse valves. Open the fine total, fine recycle, and sample back pressure valves halfway. Ensure that the nozzle is properly aligned with the sample stream. After noting the
Isokinetic sampling and proper operation of the cyclone are not achieved unless the correct
4.1.5.5 During the test run, monitor the probe and filter temperatures periodically, and make adjustments as necessary to maintain the desired temperatures. If the sample loading is high, the filter may begin to blind or the cyclone may clog. The filter or the cyclone may be replaced during the sample run. Before changing the filter or cyclone, conduct a leak-check (Section 4.1.4.2 of this method). The total particulate mass shall be the sum of all cyclone and the filter catch during the run. Monitor stack temperature and
4.2 Sample Recovery. Allow the probe to cool. When the probe can be safely handled, wipe off all external PM adhering to the outside of the nozzle, cyclone, and nozzle attachment, and place a cap over the nozzle to prevent losing or gaining PM. Do not cap the nozzle tip tightly while the sampling train is cooling, as this action would create a vacuum in the filter holder. Disconnect the probe from the umbilical connector, and take the probe to the cleanup site. Sample recovery should be conducted in a dry indoor area or, if outside, in an area protected from wind and free of dust. Cap the ends of the
4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.3 Analysis. Same as in Method 5, Section 4.3, except handle EGR Container Numbers 1 and 2 like Container Number 1 in Method 5, EGR Container Numbers 3, 4, and 5 like Container Number 3 in Method 5, and EGR Container Number 6 like Container Number 3 in Method 5. Use Figure 11 of this method to record the weights of PM collected.
4.4 Quality Control Procedures. Same as in Method 5, Section 4.4.
4.5 PM
Maintain an accurate laboratory log of all calibrations.
5.1 Probe Nozzle. Same as in Method 5, Section 5.1.
5.2 Pitot Tube. Same as in Method 5, Section 5.2.
5.3 Meter and Flow Control Console.
5.3.1 Dry Gas Meter. Same as in Method 5, Section 5.3.
5.3.2 LFE Gauges. Calibrate the recycle, total, and inlet total LFE gauges with a manometer. Read and record flow rates at 10, 50, and 90 percent of full scale on the total and recycle pressure gauges. Read and record flow rates at 10, 20, and 30 percent of full scale on the inlet total LFE pressure gauge. Record the total and recycle readings to the nearest 0.3 mm (0.01 in.). Record the inlet total LFE readings to the nearest 3 mm (0.1 in.). Make three separate measurements at each setting and calculate the average. The maximum difference between the average pressure reading and the average manometer reading shall not exceed 1 mm (0.05 in.). If the differences exceed the limit specified, adjust or replace the pressure gauge. After each field use, check the calibration of the pressure gauges.
5.3.3 Total LFE. Same as the metering system in Method 5, Section 5.3.
5.3.4 Recycle LFE. Same as the metering system in Method 5, Section 5.3, except completely close both the coarse and fine recycle valves.
5.4 Probe Heater. Connect the probe to the meter and flow control console with the umbilical connector. Insert a thermocouple into the probe sample line approximately half the length of the probe sample line. Calibrate the probe heater at 66 °C (150 °F), 121 °C (250 °F), and 177 °C (350 °F). Turn on the power, and set the probe heater to the specified temperature. Allow the heater to equilibrate, and record the thermocouple temperature and the meter and flow control console temperature to the nearest 0.5 °C (1 °F). The two temperatures should agree within 5.5 °C (10 °F). If this agreement is not met, adjust or replace the probe heater controller.
5.5 Temperature Gauges. Connect all thermocouples, and let the meter and flow control console equilibrate to ambient temperature. All thermocouples shall agree to within 1.1 °C (2.0 °F) with a standard mercury-in-glass thermometer. Replace defective thermocouples.
5.6 Barometer. Calibrate against a standard mercury-in-glass barometer.
5.7 Probe Cyclone and Nozzle Combinations. The probe cyclone and nozzle combinations need not be calibrated if the cyclone meets the design specifications in Figure 12 of this method and the nozzle meets the design specifications in appendix B of the
5.7.1 Wind Tunnel. Perform calibration and PS tests in a wind tunnel (or equivalent test apparatus) capable of establishing and maintaining the required gas stream velocities within 10 percent.
5.7.2 Particle Generation System. The particle generation system shall be capable of producing solid monodispersed dye particles with the mass median aerodynamic diameters specified in Table 2 of this method. The particle size distribution verification should be performed on an integrated sample obtained during the sampling period of each test. An acceptable alternative is to verify the size distribution of samples obtained before and after each test, with both samples required to meet the diameter and monodispersity requirements for an acceptable test run.
5.7.2.1 Establish the size of the solid dye particles delivered to the test section of the wind tunnel using the operating parameters of the particle generation system, and verify the size during the tests by microscopic examination of samples of the particles collected on a membrane filter. The particle size, as established by the operating parameters of the generation system, shall be within the tolerance specified in Table 2 of this method. The precision of the particle size verification technique shall be at least
5.7.2.2 Certify the monodispersity of the particles for each test either by microscopic inspection of collected particles on filters or by other suitable monitoring techniques such as an optical particle counter followed by a multichannel pulse height analyzer. If the proportion of multiplets and satellites in an aerosol exceeds 10 percent by mass, the particle generation system is unacceptable for purposes of this test. Multiplets are particles that are agglomerated, and satellites are particles that are smaller than the specified size range.
5.7.3 Schematic Drawings. Schematic drawings of the wind tunnel and blower system and other information showing complete procedural details of the test atmosphere generation, verification, and delivery techniques shall be furnished with calibration data to the reviewing agency.
5.7.4 Flow Rate Measurement. Determine the cyclone flow rates with a dry gas meter and a stopwatch, or a calibrated orifice system capable of measuring flow rates to within 2 percent.
5.7.5 Performance Specification Procedure. Establish the test particle generator operation and verify the particle size microscopically. If mondispersity is to be verified by measurements at the beginning and the end of the run rather than by an integrated sample, these measurements may be made at this time.
5.7.5.1 The cyclone cut size (D
5.7.5.2 Perform three replicates and calculate the average cyclone efficiency as follows:
5.7.5.3 Calculate the standard deviation (
5.7.5.4Using the cyclone flow rate that produces D
5.7.5.5Set the air velocity in the wind tunnel to one of the nominal gas velocities from Table 2 of this method. Establish isokinetic sampling conditions and the correct flow rate through the sampler (cyclone and nozzle) using recycle capacity so that the D
5.7.5.6Calculate the overall efficiency (E
5.7.5.7 Do three replicates for each combination of gas velocities and particle sizes in Table 2 of this method. Calculate E
5.7.6 Criteria for Acceptance. For each of the three gas stream velocities, plot the average E
5.8 Cyclone Calibration Procedure. The purpose of this section is to develop the relationship between flow rate, gas viscosity, gas density, and D
5.8.1 Calculate cyclone flow rate. Determine the flow rates and D
5.8.1.1 On log-log graph paper, plot the Reynolds number (Re) on the abscissa, and the square root of the Stokes 50 number [(STK
5.8.1.2 Use a linear regression analysis to determine the slope (m), and the y-intercept (b). Use the following formula to determine Q, the cyclone flow rate required for a cut size of 10
5.8.2. Directions for Using Q. Refer to Section 5 of the EGR operators manual for directions in using this expression for Q in the setup calculations.
6.1 The EGR data reduction calculations are performed by the EGR reduction computer program, which is written in IBM BASIC computer language and is available through NTIS, Accession number PB90-500000, 5285 Port Royal Road, Springfield, Virginia 22161. Examples of program inputs and outputs are shown in Figure 14 of this method.
6.1.1 Calculations can also be done manually, as specified in Method 5, Sections 6.3 through 6.7, and 6.9 through 6.12, with the addition of the following:
6.1.2 Nomenclature.
6.2 PM
6.3 Total Particulate Weight. Determine the particulate catch for PM greater than PM
6.4 PM
6.5 Total Cyclone Flow Rate. The average flow rate at standard conditions is determined from the average pressure drop across the total LFE and is calculated as follows:
The flow rate, at actual cyclone conditions, is calculated as follows:
The flow rate, at actual cyclone conditions, is calculated as follows:
6.6 Aerodynamic Cut Size. Use the following procedure to determine the aerodynamic cut size (D
6.6.1 Determine the water fraction of the mixed gas through the cyclone by using the equation below.
6.6.2 Calculate the cyclone gas viscosity as follows:
6.6.3 Calculate the molecular weight on a wet basis of the cyclone gas as follows:
6.6.4 If the cyclone meets the design specification in Figure 12 of this method, calculate the actual D
6.6.5If the cyclone does not meet the design specifications in Figure 12 of this method, then use the following equation to calculate D
6.7 Acceptable Results. Acceptability of anisokinetic variation is the same as Method 5, Section 6.12.
6.7.1 If 9.0 μm
1. Same as Bibliography in Method 5.
2. McCain, J.D., J.W. Ragland, and A.D. Williamson. Recommended Methodology for the Determination of Particles Size Distributions in Ducted Sources, Final Report. Prepared for the California Air Resources Board by Southern Research Institute. May 1986.
3. Farthing, W.E., S.S. Dawes, A.D. Williamson, J.D. McCain, R.S. Martin, and J.W. Ragland. Development of Sampling Methods for Source PM-10 Emissions. Southern Research Institute for the Environmental Protection Agency. April 1989.
4.
Figure 7. Example worksheet 1, meter orifice pressure head calculation.
Figure 8. Example worksheet 1, meter orifice pressure head calculation.
Pressure head for recycle LFE:
Figure 9. Example worksheet 3, recycle LFE pressure head.
Figure 11. EGR method analysis sheet.
Test ID. Code: Chapel Hill 2.
Test Location: Baghouse Outlet.
Test Site: Chapel Hill.
Test Date: 10/20/86.
Operators(s): JB RH MH.
1.1 Applicability. This method applies to the in-stack measurement of particulate matter (PM) emissions equal to or less than an aerodynamic diameter of nominally 10 (PM
1.2 Principle. A gas sample is extracted at a constant flow rate through an in-stack sizing device, which separates PM greater than PM
Methods cited in this method are part of 40 CFR part 60, appendix A.
2.1 Sampling Train. A schematic of the Method 201A sampling train is shown in Figure 1 of this method. With the exception of the PM
2.1.1 Nozzle. Stainless steel (316 or equivalent) with a sharp tapered leading edge. Eleven nozzles that meet the design specification in Figure 2 of this method are recommended. A larger number of nozzles with small nozzle increments increase the likelihood that a single nozzle can be used for the entire traverse. If the nozzles do not meet the design specifications in Figure 2 of this method, then the nozzles must meet the criteria in Section 5.2 of this method.
2.1.2 PM
2.1.3 Filter Holder. 63-mm, stainless steel. An Andersen filter, part number SE274, has been found to be acceptable for the in-stack filter.
2.1.4 Pitot Tube. Same as in Method 5, Section 2.1.3. The pitot lines shall be made of heat resistant tubing and attached to the probe with stainless steel fittings.
2.1.5 Probe Liner. Optional, same as in Method 5, Section 2.1.2.
2.1.6 Differential Pressure Gauge, Condenser, Metering System, Barometer, and Gas Density Determination Equipment. Same as in Method 5, Sections 2.1.4, and 2.1.7 through 2.1.10, respectively.
2.2 Sample Recovery.
2.2.1 Nozzle, Sizing Device, Probe, and Filter Holder Brushes. Nylon bristle brushes with stainless steel wire shafts and handles, properly sized and shaped for cleaning the nozzle, sizing device, probe or probe liner, and filter holders.
2.2.2 Wash Bottles, Glass Sample Storage Containers, Petri Dishes, Graduated Cylinder and Balance, Plastic Storage Containers, Funnel and Rubber Policeman, and Funnel. Same as in Method 5, Sections 2.2.2 through 2.2.8, respectively.
2.3 Analysis. Same as in Method 5, Section 2.3.
The reagents for sampling, sample recovery, and analysis are the same as that specified in Method 5, Sections 3.1, 3.2, and 3.3, respectively.
4.1 Sampling. The complexity of this method is such that, in order to obtain reliable results, testers should be trained and experienced with the test procedures.
4.1.1 Pretest Preparation. Same as in Method 5, Section 4.1.1.
4.1.2 Preliminary Determinations. Same as in Method 5, Section 4.1.2, except use the directions on nozzle size selection and sampling time in this method. Use of any nozzle greater than 0.16 in. in diameter requires a sampling port diameter of 6 inches. Also, the required maximum number of traverse points at any location shall be 12.
4.1.2.1 The sizing device must be in-stack or maintained at stack temperature during sampling. The blockage effect of the CSR sampling assembly will be minimal if the cross-sectional area of the sampling assembly is 3 percent or less of the cross-sectional area of the duct. If the cross-sectional area of the assembly is greater than 3 percent of the cross-sectional area of the duct, then either determine the pitot coefficient at sampling conditions or use a standard pitot with a known coefficient in a configuration with the CSR sampling assembly such that flow disturbances are minimized.
4.1.2.2 The setup calculations can be performed by using the following procedures.
4.1.2.2.1 In order to maintain a cut size of 10 μm in the sizing device, the flow rate through the sizing device must be maintained at a constant, discrete value during the run. If the sizing device is a cyclone that meets the design specifications in Figure 3 of this method, use the equations in Figure 4 of this method to calculate three orifice heads (
4.1.2.2.2 If the sizing device is a cyclone that does not meet the design specifications in Figure 3 of this method, use the equations in Figure 4 of this method, except use the procedures in Section 5.3 of this method to determine Q
4.1.2.2.3 To select a nozzle, use the equations in Figure 5 of this method to calculate
4.1.2.2.4 Correct the Method 2 pitot readings to Method 201A pitot readings by multiplying the Method 2 pitot readings by the square of a ratio of the Method 201A pitot coefficient to the Method 2 pitot coefficient. Select the nozzle for which
4.1.2.2.5 Vary the dwell time, or sampling time, at each traverse point proportionately with the point velocity. Use the equations in Figure 6 of this method to calculate the dwell time at the first point and at each subsequent point. It is recommended that the number of minutes sampled at each point be rounded to the nearest 15 seconds.
4.1.3 Preparation of Collection Train. Same as in Method 5, Section 4.1.3, except omit directions about a glass cyclone.
4.1.4 Leak-Check Procedure. The sizing device is removed before the post-test leak-check to prevent any disturbance of the collected sample prior to analysis.
4.1.4.1 Pretest Leak-Check. A pretest leak-check of the entire sampling train, including the sizing device, is required. Use the leak-check procedure in Method 5, Section 4.1.4.1 to conduct a pretest leak-check.
4.1.4.2 Leak-Checks During Sample Run. Same as in Method 5, Section 4.1.4.1.
4.1.4.3 Post-Test Leak-Check. A leak-check is required at the conclusion of each sampling run. Remove the cyclone before the leak-check to prevent the vacuum created by the cooling of the probe from disturbing the collected sample and use the procedure in Method 5, Section 4.1.4.3 to conduct a post-test leak-check.
4.1.5 Method 201A Train Operation. Same as in Method 5, Section 4.1.5, except use the procedures in this section for isokinetic sampling and flow rate adjustment. Maintain the flow rate calculated in Section 4.1.2.2.1 of this method throughout the run provided the stack temperature is within 28 °C (50 °F) of the temperature used to calculate
4.2 Sample Recovery. If a cascade impactor is used, use the manufacturer's recommended procedures for sample recovery. If a cyclone is used, use the same sample recovery as that in Method 5, Section 4.2, except an increased number of sample recovery containers is required.
4.2.1
4.2.3
4.2.4
4.2.6
4.2.7
4.3 Analysis. Same as in Method 5, Section 4.3, except handle Method 201A Container Number 1 like Container Number 1, Method 201A Container Numbers 2 and 3 like Container Number 2, and Method 201A Container Number 4 like Container Number 3. Use Figure 7 of this method to record the weights of PM collected. Use Figure 5-3 in Method 5, Section 4.3, to record the volume of water collected.
4.4 Quality Control Procedures. Same as in Method 5, Section 4.4.
4.5 PM
Maintain an accurate laboratory log of all calibrations.
5.1 Probe Nozzle, Pitot Tube, Metering System, Probe Heater Calibration, Temperature Gauges, Leak-check of Metering System, and Barometer. Same as in Method 5, Section 5.1 through 5.7, respectively.
5.2 Probe Cyclone and Nozzle Combinations. The probe cyclone and nozzle combinations need not be calibrated if both meet design specifications in Figures 2 and 3 of this method. If the nozzles do not meet design specifications, then test the cyclone and nozzle combinations for conformity with performance specifications (PS's) in Table 1 of this method. If the cyclone does not meet design specifications, then the cylcone and nozzle combination shall conform to the PS's and calibrate the cyclone to determine the relationship between flow rate, gas viscosity, and gas density. Use the procedures in Section 5.2 of this method to conduct PS tests and the procedures in Section 5.3 of this method to calibrate the cyclone. The purpose of the PS tests are to conform that the cyclone and nozzle combination has the desired sharpness of cut. Conduct the PS tests in a wind tunnel described in Section 5.2.1 of this method and particle generation system described in Section 5.2.2 of this method. Use five particle sizes and three wind velocities as listed in Table 2 of this method. A minimum of three replicate measurements of collection efficiency shall be performed for each of the 15 conditions listed, for a minimum of 45 measurements.
5.2.1 Wind Tunnel. Perform the calibration and PS tests in a wind tunnel (or equivalent test apparatus) capable of establishing and maintaining the required gas stream velocities within 10 percent.
5.2.2 Particle Generation System. The particle generation system shall be capable of producing solid monodispersed dye particles with the mass median aerodynamic diameters specified in Table 2 of this method. Perform the particle size distribution verification on an integrated sample obtained during the sampling period of each test. An acceptable alternative is to verify the size distribution of samples obtained before and after each test, with both samples required to meet the diameter and monodispersity requirements for an acceptable test run.
5.2.2.1 Establish the size of the solid dye particles delivered to the test section of the wind tunnel by using the operating parameters of the particle generation system, and verify them during the tests by microscopic examination of samples of the particles collected on a membrane filter. The particle size, as established by the operating parameters of the generation system, shall be within the tolerance specified in Table 2 of this method. The precision of the particle size verification technique shall be at least
5.2.2.2 Certify the monodispersity of the particles for each test either by microscopic inspection of collected particles on filters or by other suitable monitoring techniques such as an optical particle counter followed by a multichannel pulse height analyzer. If the proportion of multiplets and satellites in an aerosol exceeds 10 percent by mass, the particle generation system is unacceptable for the purpose of this test. Multiplets are particles that are agglomerated, and satellites are particles that are smaller than the specified size range.
5.2.3 Schematic Drawings. Schematic drawings of the wind tunnel and blower system and other information showing complete procedural details of the test atmosphere generation, verification, and delivery techniques shall be furnished with calibration data to the reviewing agency.
5.2.4 Flow Measurements. Measure the cyclone air flow rates with a dry gas meter and a stopwatch, or a calibrated orifice system capable of measuring flow rates to within 2 percent.
5.2.5 Performance Specification Procedure. Establish test particle generator operation and verify particle size microscopically. If monodisperity is to be verified by measurements at the beginning and the end of the run rather than by an integrated sample, these measurements may be made at this time.
5.2.5.1 The cyclone cut size, or D
5.2.5.2.Do three replicates and calculate the average cyclone efficiency [E
5.2.5.3Calculate the standard deviation (
5.2.5.4 Measure the overall efficiency of the cyclone and nozzle, E
5.2.5.5 Set the air velocity and particle size from one of the conditions in Table 2 of this method. Establish isokinetic sampling conditions and the correct flow rate in the cyclone (obtained by procedures in this section) such that the D
5.2.5.6 Do three replicates for each combination of gas velocity and particle size in Table 2 of this method. Use the equation
5.2.5.7 Use the formula in Section 5.2.5.3 to calculate
5.2.6 Criteria for Acceptance. For each of the three gas stream velocities, plot the E
5.3 Cyclone Calibration Procedure. The purpose of this procedure is to develop the relationship between flow rate, gas viscosity, gas density, and D
5.3.1 Calculate Cyclone Flow Rate. Determine flow rates and D
5.3.1.1 On log-log graph paper, plot the Reynolds number (Re) on the abscissa, and the square root of the Stokes 50 number [(Stk
5.3.1.2 Use a linear regression analysis to determine the slope (m) and the Y-intercept (b). Use the following formula to determine Q, the cyclone flow rate required for a cut size of 10
5.3.1.3 Refer to the Method 201A operators manual, entitled
5.4 Cascade Impactor. The purpose of calibrating a cascade impactor is to determine the empirical constant (STK
5.4.1 Wind Tunnel. Same as in Section 5.2.1 of this method.
5.4.2 Particle Generation System. Same as in Section 5.2.2 of this method.
5.4.3 Hardware Configuration for Calibrations. An impaction stage constrains an aerosol to form circular or rectangular jets, which are directed toward a suitable substrate where the larger aerosol particles are collected. For calibration purposes, three stages of the cascade impactor shall be discussed and designated calibration stages 1, 2, and 3. The first calibration stage consists of the collection substrate of an impaction stage and all upstream surfaces up to and including the nozzle. This may include other preceding impactor stages. The second and
5.4.3.1 It is expected, but not necessary, that the complete hardware assembly will be used in each of the sampling runs of the calibration and performance determinations. Only the first calibration stage must be tested under isokinetic sampling conditions. The second and third calibration stages must be calibrated with the collection substrate of the preceding calibration stage in place, so that gas flow patterns existing in field operation will be simulated.
5.4.3.2 Each of the PM
5.4.4 Calibration Procedure. Establish test particle generator operation and verify particle size microscopically. If monodispersity is to be verified by measurements at the beginning and the end of the run rather than by an integrated sample, these measurements shall be made at this time. Measure in triplicate the PM collected by the calibration stage (m) and the PM on all surfaces downstream of the respective calibration stage (m') for all of the flow rates and particle size combinations shown in Table 2 of this method. Techniques of mass measurement may include the use of a dye and spectrophotometer. Particles on the upstream side of a jet plate shall be included with the substrate downstream, except agglomerates of particles, which shall be included with the preceding or upstream substrate. Use the following formula to calculate the collection efficiency (E) for each stage.
5.4.4.1 Use the formula in Section 5.2.5.3 of this method to calculate the standard deviation (
5.4.4.2 Use the following formula to calculate the average collection efficiency (E
E
5.4.4.3 Use the following formula to calculate Stk for each E
5.4.4.4 Determine Stk
5.4.4.5 The Stk
5.4.5 Criteria For Acceptance. Plot E
6.2 Analysis of Cascade Impactor Data. Use the manufacturer's recommended procedures to analyze data from cascade impactors.
6.3 Analysis of Cyclone Data. Use the following procedures to analyze data from a single stage cyclone.
6.3.1 PM
6.3.2 Total PM Weight (optional). Determine the PM catch for greater than PM
6.3.3 PM
6.3.4 Aerodynamic Cut Size. Calculate the stack gas viscosity as follows:
μ
6.3.4.1 The PM
6.3.4.2 Calculate the molecular weight on a wet basis of the stack gas as follows:
6.3.4.3 Calculate the actual D
6.3.5 Acceptable Results. The results are acceptable if two conditions are met. The first is that 9.0
1. Same as Bibliography in Method 5.
2. McCain, J.D., J.W. Ragland, and A.D. Williamson. Recommended Methodology for the Determination of Particle Size Distributions in Ducted Sources, Final Report. Prepared for the California Air Resources Board by Southern Research Institute. May 1986.
3. Farthing, W.E., S.S. Dawes, A.D. Williamson, J.D. McCain, R.S. Martin, and J.W. Ragland. Development of Sampling Methods for Source PM
4.
Barometric pressure,
Stack static pressure,
Average stack temperature,
Meter temperature, t
Orifice
Fraction moisture content,
Figure 4. Example worksheet 1, cyclone flow rate and
Stack viscosity, μ
Absolute stack pressure,
Average stack temperature,
Meter temperature, t
Method 201A pitot coefficient,
Cyclone flow rate, ft
Method 2 pitot coefficient,
Molecular weight of stack gas, wet basis,
Nozzle diameter, D
Maximum and minimum velocities:
Calculate R
If R
Eq. 1 v
Eq. 2 v
Calculate R
If R
Eq. 3 v
Eq. 4 v
Figure 5. Example worksheet 2, nozzle selection.
Figure 6. Example worksheet 3, dwell time.
Plant
Date
Run no.
Filter no.
Amount of liquid lost during
Acetone blank volume, ml
Acetone wash volume, ml (4)
Acetone blank conc., mg/mg (Equation 5-4,
Acetone wash blank, mg (Equation 5-5,
Figure 7. Method 201A analysis sheet.
1.1 Applicability.
1.1.1 This method applies to the determination of condensible particulate matter (CPM) emissions from stationary sources. It is intended to represent condensible matter as material that condenses after passing through a filter and as measured by this method (Note: The filter catch can be analyzed according to the appropriate method).
1.1.2 This method may be used in conjunction with Method 201 or 201A if the probes are glass-lined. Using Method 202 in conjunction with Method 201 or 201A, only the impinger train configuration and analysis is addressed by this method. The sample train operation and front end recovery and analysis shall be conducted according to Method 201 or 201A.
1.1.3 This method may also be modified to measure material that condenses at other temperatures by specifying the filter and probe temperature. A heated Method 5 out-of-stack filter may be used instead of the in-stack filter to determine condensible emissions at wet sources.
1.2 Principle.
1.2.1 The CPM is collected in the impinger portion of a Method 17 (appendix A, 40 CFR part 60) type sampling train. The impinger contents are immediately purged after the run with nitrogen (N
1.2.2 The potential for low collection efficiency exist at oil-fired boilers. To improve the collection efficiency at these type of sources, an additional filter placed between the second and third impinger is recommended.
2.1 Precision. The precision based on method development tests at an oil-fired boiler and a catalytic cracker were 11.7 and 4.8 percent, respectively.
2.2 Interference. Ammonia. In sources that use ammonia injection as a control technique for hydrogen chloride (HC1), the ammonia interferes by reacting with HC1 in the gas stream to form ammonium chloride (NH
3.1 Sampling Train. Same as in Method 17, section 2.1, with the following exceptions noted below (see Figure 202-1).
3.1.1 The probe extension shall be glass-lined or Teflon.
3.1.2 Both the first and second impingers shall be of the Greenburg-Smith design with the standard tip.
3.1.3 All sampling train glassware shall be cleaned prior to the test with soap and tap water, water, and rinsed using tap water, water, acetone, and finally, MeCl
3.2 Sample Recovery. Same as in Method 17, section 2.2, with the following additions:
3.2.1 N
3.2.2 Rotameter. Capable of measuring gas flow at 20 liters/min.
3.3 Analysis. The following equipment is necessary in addition to that listed in Method 17, section 2.3:
3.3.1 Separatory Funnel. Glass, 1-liter.
3.3.2 Weighing Tins. 350-ml.
3.3.3 Dry Equipment. Hot plate and oven with temperature control.
3.3.4 Pipets. 5-ml.
3.3.5 Ion Chromatograph. Same as in Method 5F, Section 2.1.6.
Unless otherwise indicated, all reagents must conform to the specifications established by the Committee on Analytical Reagents of the American Chemical Society. Where such specifications are not available, use the best available grade.
4.1 Sampling. Same as in Method 17, section 3.1, with the addition of deionized distilled water to conform to the American Society for Testing and Materials Specification D 1193-74, Type II and the omittance of section 3.1.4.
4.2 Sample Recovery. Same as in Method 17, section 3.2, with the following additions:
4.2.1 N
4.2.2 Methylene Chloride, ACS grade. Blanks shall be run prior to use and only methylene chloride with low blank values (0.001 percent) shall be used.
4.2.3 Water. Same as in section 4.1.
4.3 Analysis. Same as in Method 17, section 3.3, with the following additions:
4.3.1 Methylene Chloride. Same as section 4.2.2.
4.3.2 Ammonium Hydroxide. Concentrated (14.8 M) NH
4.3.3 Water. Same as in section 4.1.
4.3.4 Phenolphthalein. The pH indicator solution, 0.05 percent in 50 percent alcohol.
5.1 Sampling. Same as in Method 17, section 4.1, with the following exceptions:
5.1.1 Place 100 ml of water in the first three impingers.
5.1.2 The use of silicone grease in train assembly is not recommended because it is very soluble in MeCl
5.2 Sample Recovery. Same as in Method 17, section 4.2 with the addition of a post-test N
5.2.1 Post-test N
5.2.2 Sample Handling.
5.2.2.1 Container Nos. 1, 2, and 3. If filter catch is to be determined, as detailed in Method 17, section 4.2.
5.2.2.2 Container No. 4 (Impinger Contents). Measure the liquid in the first three impingers to within 1 ml using a clean graduated cylinder or by weighing it to within 0.5 g using a balance. Record the volume or weight of liquid present to be used to calculate the moisture content of the effluent gas. Quantitatively transfer this liquid into a clean sample bottle (glass or plastic); rinse each impinger and the connecting glassware, including probe extension, twice with water, recover the rinse water, and add it to the same sample bottle. Mark the liquid level on the bottle.
5.2.2.3 Container No. 5 (MeCl
5.2.2.4 Container No. 6 (Water Blank). Once during each field test, place 500 ml of water in a separate sample container.
5.2.2.5 Container No. 7 (MeCl
5.3 Analysis. Record the data required on a sheet such as the one shown in Figure 202-3. Handle each sample container as follows:
5.3.1 Container Nos. 1, 2, and 3. If filter catch is analyzed, as detailed in Method 17, section 4.3.
5.3.2 Container Nos. 4 and 5. Note the level of liquid in the containers and confirm on the analytical data sheet whether leakage occurred during transport. If a noticeable amount of leakage has occurred, either void the sample or use methods, subject to the approval of the Administrator, to correct the final results. Measure the liquid in Container No. 4 either volumetrically to
5.3.2.1 Extraction. Separate the organic fraction of the sample by adding the contents of Container No. 4 (MeCl
5.3.2.2 Organic Fraction Weight Determination (Organic Phase from Container Nos. 4 and 5). Evaporate the organic extract at room temperature and pressure in a laboratory hood. Following evaporation, desiccate the organic fraction for 24 hours in a desiccator containing anhydrous calcium sulfate. Weigh to a constant weight and report the results to the nearest 0.1 mg.
5.3.2.3 Inorganic Fraction Weight Determination. (Note: If NH
5.3.2.4 Analysis of Sulfate by IC to Determine Ammonium Ion (NH
5.3.3 Analysis of Water and MeCl
5.3.4 Analysis of Acetone Blank (Container No. 8). Same as in Method 17, section 4.3.
Same as in Method 17, section 5, except for the following:
6.1 IC Calibration. Same as Method 5F, section 5.
6.2 Audit Procedure. Concurrently, analyze the audit sample and a set of compliance samples in the same manner to evaluate the technique of the analyst and the standards preparation. The same analyst, analytical reagents, and analytical system shall be used both for compliance samples and the EPA audit sample. If this condition is met, auditing of subsequent compliance analyses for the same enforcement agency within 30 days is not required. An audit sample set may not be used to validate different sets of compliance samples under the jurisdiction of different enforcement agencies, unless prior arrangements are made with both enforcement agencies.
6.3 Audit Samples. Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing:
6.4 Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
Same as in Method 17, section 6, with the following additions:
7.1 Nomenclature. Same as in Method 17, section 6.1 with the following additions.
7.2 Correction for NH
7.3Mass of Inorganic CPM.
Concentration of CPM.
8.1 Determination of NH
8.1.1 An alternative procedure to determine the amount of NH
8.1.2 Calculate the concentration of SO
8.3.1 Calculate the CPM as described in section 7.
8.2 Analysis of Chlorides by IC. At the conclusion of the final weighing as described in section 5.3.2.3, redissolve the inorganic fraction in 100 ml of water. Analyze an aliquot of the redissolved sample for chlorides by IC using techniques similar to those described in Method 5F for sulfates. Previous drying of the sample should have removed all HCl. Therefore, the remaining chlorides measured by IC can be assumed to be NH
8.3 Air Purge to Remove SO
8.4 Chloroform-ether Extraction. As an alternative to the methylene chloride extraction described in section 5.3.2.1, the tester may opt to conduct a chloroform-ether extraction. Note: The Chloroform-ether was not as effective as the MeCl
8.4.1 Add the contents of Container No. 4 to a 1000-ml separatory funnel. Then add 75 ml of chloroform to the funnel, mix well, and drain off the lower organic phase. Repeat two more times with 75 ml of chloroform. Then perform three extractions with 75 ml of diethylether. This extraction should yield approximately 450 ml of organic extraction. Each time, leave a small amount of the organic/MeCl
8.4.2 Add the contents of Container No. 5 to the organic extraction. Place approximately 300 ml of the organic extract in a tared 350-ml weighing tin while storing the remaining organic extract in a sample container. As the organic extract evaporates, add the remaining extract to the weighing tin.
8.4.3 Determine the weight of the organic phase as described in Section 5.3.2.2.
8.5 Improving Collection Efficiency. If low impinger collection efficiency is suspected, the following procedure may be used.
8.5.1 Place an out-of-stock filter as described in Method 8 between the second and third impingers.
8.5.2 Recover and analyze the filter according to Method 17, Section 4.2. Include the filter holder as part of the connecting glassware and handle as described in sections 5.2.2.2 and 5.2.2.3.
8.5.3 Calculate the Concentration of CPM as follows:
8.6 Wet Source Testing. When testing at a wet source, use a heated out-of-stack filter as described in Method 5.
1. DeWees, W.D., S.C. Steinsberger, G.M. Plummer, L.T. Lay, G.D. McAlister, and R.T. Shigehara. “Laboratory and Field Evaluation of the EPA Method 5 Impinger Catch for Measuring Condensible Matter from Stationary Sources.” Paper presented at the 1989 EPA/AWMA International Symposium on Measurement of Toxic and Related Air Pollutants. Raleigh, North Carolina. May 1-5, 1989.
2. DeWees, W.D. and K.C. Steinsberger. “Method Development and Evaluation of Draft Protocol for Measurement of Condensible Particulate Emissions.” Draft Report. November 17, 1989.
3. Texas Air Control Board, Laboratory Division. “Determination of Particulate in Stack Gases Containing Sulfuric Acid and/or Sulfur Dioxide.”
4. Nothstein, Greg. Masters Thesis. University of Washington. Department of Environmental Health. Seattle, Washington.
5. “Particulate Source Test Procedures Adopted by Puget Sound Air Pollution Control Agency Board of Directors.” Puget Sound Air Pollution Control Agency, Engineering Division. Seattle, Washington. August 11, 1983.
6. Commonwealth of Pennsylvania, Department of Environmental Resources. Chapter 139, Sampling and Testing (Title 25, Rules and Regulations, Part I, Department of Environmental Resources, Subpart C, Protection of Natural Resources, Article III, Air Resources). January 8, 1960.
7. Wisconsin Department of Natural Resources.
This procedure is used to determine whether a permanent or temporary enclosure meets the criteria for a total enclosure. An existing building may be used as a temporary or permanent enclosure as long as it meets the appropriate criteria described in this method.
An enclosure is evaluated against a set of criteria. If the criteria are met and if all the exhaust gases from the enclosure are ducted to a control device, then the volatile organic compounds (VOC) capture efficiency (CE) is assumed to be 100 percent, and CE need not be measured. However, if part of the exhaust gas stream is not ducted to a control device, CE must be determined.
3.1Natural Draft Opening (NDO). Any permanent opening in the enclosure that remains open during operation of the facility and is not connected to a duct in which a fan is installed.
3.2Permanent Total Enclosure (PE). A permanently installed enclosure that completely surrounds a source of emissions such that all VOC emissions are captured and contained for discharge to a control device.
3.3Temporary Total Enclosure (TTE). A temporarily installed enclosure that completely surrounds a source of emissions such that all VOC emissions that are not directed through the control device (i.e. uncaptured) are captured by the enclosure and contained for discharge through ducts that allow for the accurate measurement of the uncaptured VOC emissions.
3.4Building Enclosure (BE). An existing building that is used as a TTE.
An evaluation of the proposed building materials and the design for the enclosure is recommended to minimize any potential hazards.
5.1Any NDO shall be at least four equivalent opening diameters from each VOC emitting point unless otherwise specified by the Administrator.
5.2Any exhaust point from the enclosure shall be at least four equivalent duct or hood diameters from each NDO.
5.3The total area of all NDO's shall not exceed 5 percent of the surface area of the enclosure's four walls, floor, and ceiling.
5.4The average facial velocity (FV) of air through all NDO's shall be at least 3,600 m/hr (200 fpm). The direction of air flow through all NDO's shall be into the enclosure.
5.5All access doors and windows whose areas are not included in section 5.3 and are not included in the calculation in section 5.4 shall be closed during routine operation of the process.
6.1Same as sections 5.1 and 5.3 through 5.5.
6.2All VOC emissions must be captured and contained for discharge through a control device.
7.1The success of this method lies in designing the TTE to simulate the conditions that exist without the TTE (i.e., the effect of the TTE on the normal flow patterns around the affected facility or the amount of uncaptured VOC emissions should be minimal). The TTE must enclose the application stations, coating reservoirs, and all areas from the application station to the oven. The oven does not have to be enclosed if it is under negative pressure. The NDO's of the temporary enclosure and an exhaust fan must be properly sized and placed.
7.2Estimate the ventilation rate of the TTE that best simulates the conditions that exist without the TTE (i.e., the effect of the TTE on the normal flow patterns around the affected facility or the amount of uncaptured VOC emissions should be minimal). Figure 204-1 or the following equation may be used as an aid.
7.3Monitor the VOC concentration of the captured gas steam in the duct before the capture device without the TTE. To minimize the effect of temporal variation on the captured emissions, the baseline measurement should be made over as long a time period as practical. However, the process conditions must be the same for the measurement in section 7.5 as they are for this baseline measurement. This may require short measuring times for this quality control check before and after the construction of the TTE.
7.4After the TTE is constructed, monitor the VOC concentration inside the TTE. This concentration should not continue to increase, and must not exceed the safe level according to Occupational Safety and Health Administration requirements for permissible exposure limits. An increase in VOC concentration indicates poor TTE design.
7.5Monitor the VOC concentration of the captured gas stream in the duct before the capture device with the TTE. To limit the effect of the TTE on the process, the VOC concentration with and without the TTE must be within 10 percent. If the measurements do not agree, adjust the ventilation rate from the TTE until they agree within 10 percent.
8.1Determine the equivalent diameters of the NDO's and determine the distances from each VOC emitting point to all NDO's. Determine the equivalent diameter of each exhaust duct or hood and its distance to all NDO's. Calculate the distances in terms of equivalent diameters. The number of equivalent diameters shall be at least four.
8.2Measure the total surface area (A
8.3Measure the volumetric flow rate, corrected to standard conditions, of each gas stream exiting the enclosure through an exhaust duct or hood using EPA Method 2. In some cases (e.g., when the building is the enclosure), it may be necessary to measure the volumetric flow rate, corrected to standard conditions, of each gas stream entering the enclosure through a forced makeup air duct using Method 2. Calculate FV using the following equation:
The FV shall be at least 3,600 m/hr (200 fpm). Alternatively, measure the pressure differential across the enclosure. A pressure drop of 0.013 mm Hg (0.007 in. H
8.4Verify that the direction of air flow through all NDO's is inward. If FV is less than 9,000 m/hr (500 fpm), the continuous inward flow of air shall be verified using streamers, smoke tubes, or tracer gases. Monitor the direction of air flow for at least 1 hour, with checks made no more than 10 minutes apart. If FV is greater than 9,000 m/hr (500 fpm), the direction of air flow through the NDOs shall be presumed to be inward at all times without verification.
1.1Applicability. This procedure is applicable for determining the input of volatile organic compounds (VOC). It is intended to be used in the development of liquid/gas protocols for determining VOC capture efficiency (CE) for surface coating and printing operations.
1.2Principle. The amount of VOC introduced to the process (L) is the sum of the products of the weight (W) of each VOC containing liquid (ink, paint, solvent, etc.) used and its VOC content (V).
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
The amount of VOC containing liquid introduced to the process is determined as the weight difference of the feed material before and after each sampling run. The VOC content of the liquid input material is determined by volatilizing a small aliquot of the material and analyzing the volatile material using a flame ionization analyzer (FIA). A sample of each VOC containing liquid is analyzed with an FIA to determine V.
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Liquid Weight.
4.1.1Balances/Digital Scales. To weigh drums of VOC containing liquids to within 0.2 lb or 1.0 percent of the total weight of VOC liquid used.
4.1.2Volume Measurement Apparatus (Alternative). Volume meters, flow meters, density measurement equipment, etc., as needed to achieve the same accuracy as direct weight measurements.
4.2VOC Content (FIA Technique). The liquid sample analysis system is shown in Figures 204A-1 and 204A-2. The following equipment is required:
4.2.1Sample Collection Can. An appropriately-sized metal can to be used to collect VOC containing materials. The can must be constructed in such a way that it can be grounded to the coating container.
4.2.2Needle Valves. To control gas flow.
4.2.3Regulators. For carrier gas and calibration gas cylinders.
4.2.4Tubing. Teflon or stainless steel tubing with diameters and lengths determined by connection requirements of equipment. The tubing between the sample oven outlet and the FIA shall be heated to maintain a temperature of 120
4.2.5Atmospheric Vent. A tee and 0- to 0.5-liter/min rotameter placed in the sampling line between the carrier gas cylinder and the VOC sample vessel to release the excess carrier gas. A toggle valve placed between the tee and the rotameter facilitates leak tests of the analysis system.
4.2.6Thermometer. Capable of measuring the temperature of the hot water bath to within 1 °C.
4.2.7Sample Oven. Heated enclosure, containing calibration gas coil heaters, critical orifice, aspirator, and other liquid sample analysis components, capable of maintaining a temperature of 120
4.2.8Gas Coil Heaters. Sufficient lengths of stainless steel or Teflon tubing to allow zero and calibration gases to be heated to the sample oven temperature before entering the critical orifice or aspirator.
4.2.9Water Bath. Capable of heating and maintaining a sample vessel temperature of 100
4.2.10Analytical Balance. To measure
4.2.11Disposable Syringes. 2-cc or 5-cc.
4.2.12Sample Vessel. Glass, 40-ml septum vial. A separate vessel is needed for each sample.
4.2.13Rubber Stopper. Two-hole stopper to accommodate 3.2-mm (
4.2.14Critical Orifices. Calibrated critical orifices capable of providing constant flow rates from 50 to 250 ml/min at known pressure drops. Sapphire orifice assemblies (available from O'Keefe Controls Company) and glass capillary tubing have been found to be adequate for this application.
4.2.15Vacuum Gauge. Zero to 760-mm (0- to 30-in.) Hg U-Tube manometer or vacuum gauge.
4.2.16Pressure Gauge. Bourdon gauge capable of measuring the maximum air pressure at the aspirator inlet (e.g., 100 psig).
4.2.17Aspirator. A device capable of generating sufficient vacuum at the sample vessel to create critical flow through the calibrated orifice when sufficient air pressure is present at the aspirator inlet. The aspirator must also provide sufficient sample pressure to operate the FIA. The sample is also mixed with the dilution gas within the aspirator.
4.2.18Soap Bubble Meter. Of an appropriate size to calibrate the critical orifices in the system.
4.2.19Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated that they would provide more accurate measurements. The FIA instrument should be the same instrument used in the gaseous analyses adjusted with the same
4.2.19.1Zero Drift. Less than
4.2.19.2Calibration Drift. Less than
4.2.19.3Calibration Error. Less than
4.2.20Integrator/Data Acquisition System. An analog or digital device or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is one measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.
4.2.21Chart Recorder (Optional). A chart recorder or similar device is recommended to provide a continuous analog display of the measurement results during the liquid sample analysis.
5.1Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.1.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H2/60 percent He or 40 percent H
5.1.2Carrier Gas. High purity air with less than 1 ppm of organic material (as propane) or less than 0.1 percent of the span value, whichever is greater.
5.1.3FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentrations of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown to the Administrator's satisfaction that equally accurate measurements would be achieved.
5.1.4System Calibration Gas. Gas mixture standard containing propane in air, approximating the undiluted VOC concentration expected for the liquid samples.
6.1Samples must be collected in a manner that prevents or minimizes loss of volatile components and that does not contaminate the coating reservoir.
6.2Collect a 100-ml or larger sample of the VOC containing liquid mixture at each application location at the beginning and end of each test run. A separate sample should be taken of each VOC containing liquid added to the application mixture during the test run. If a fresh drum is needed during the sampling run, then obtain a sample from the fresh drum.
6.3When collecting the sample, ground the sample container to the coating drum. Fill the sample container as close to the rim as possible to minimize the amount of headspace.
6.4After the sample is collected, seal the container so the sample cannot leak out or evaporate.
6.5Label the container to clearly identify the contents.
7.1Required instrument quality control parameters are found in the following sections:
7.1.1The FIA system must be calibrated as specified in section 8.1.
7.1.2The system drift check must be performed as specified in section 8.2.
7.2Audits.
7.2.1Audit Procedure. Concurrently, analyze the audit sample and a set of compliance samples in the same manner to evaluate the technique of the analyst and the standards preparation. The same analyst, analytical reagents, and analytical system shall be used both for compliance samples and the EPA audit sample. If this condition is met, auditing of subsequent compliance analyses for the same enforcement agency within 30 days is not required. An audit sample set may not be used to validate different sets of compliance samples under the jurisdiction of different enforcement agencies, unless prior arrangements are made with both enforcement agencies.
7.2.2Audit Samples and Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B), Quality Assurance Division, Atmospheric Research and
7.2.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
8.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero- and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low- and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all four gases are within 5 percent of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system.
8.2Systems Drift Checks. After each sample, repeat the system calibration checks in section 9.2.7 before any adjustments to the FIA or measurement system are made. If the zero or calibration drift exceeds
Alternatively, recalibrate the FIA as in section 8.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run.
8.3Critical Orifice Calibration.
8.3.1Each critical orifice must be calibrated at the specific operating conditions under which it will be used. Therefore, assemble all components of the liquid sample analysis system as shown in Figure 204A-3. A stopwatch is also required.
8.3.2Turn on the sample oven, sample line, and water bath heaters, and allow the system to reach the proper operating temperature. Adjust the aspirator to a vacuum of 380 mm (15 in.) Hg vacuum. Measure the time required for one soap bubble to move a known distance and record barometric pressure.
8.3.3Repeat the calibration procedure at a vacuum of 406 mm (16 in.) Hg and at 25-mm (1-in.) Hg intervals until three consecutive determinations provide the same flow rate. Calculate the critical flow rate for the orifice in ml/min at standard conditions. Record the vacuum necessary to achieve critical flow.
9.1Determination of Liquid Input Weight.
9.1.1Weight Difference. Determine the amount of material introduced to the process as the weight difference of the feed material before and after each sampling run. In determining the total VOC containing liquid usage, account for:
(a) The initial (beginning) VOC containing liquid mixture.
(b) Any solvent added during the test run.
(c) Any coating added during the test run.
(d) Any residual VOC containing liquid mixture remaining at the end of the sample run.
9.1.1.1Identify all points where VOC containing liquids are introduced to the process. To obtain an accurate measurement of VOC containing liquids, start with an empty fountain (if applicable). After completing the run, drain the liquid in the fountain back into the liquid drum (if possible) and weigh the drum again. Weigh the VOC containing liquids to
9.1.1.2If it is not possible to measure a single representative mixture, then weigh the various components separately (e.g., if solvent is added during the sampling run, weigh the solvent before it is added to the mixture). If a fresh drum of VOC containing liquid is needed during the run, then weigh both the empty drum and fresh drum.
9.1.2Volume Measurement (Alternative). If direct weight measurements are not feasible, the tester may use volume meters or flow rate meters and density measurements to determine the weight of liquids used if it can be demonstrated that the technique produces results equivalent to the direct weight measurements. If a single representative
9.2Determination of VOC Content in Input Liquids
9.2.1 Assemble the liquid VOC content analysis system as shown in Figure 204A-1.
9.2.2Permanently identify all of the critical orifices that may be used. Calibrate each critical orifice under the expected operating conditions (i.e., sample vacuum and temperature) against a volume meter as described in section 8.3.
9.2.3Label and tare the sample vessels (including the stoppers and caps) and the syringes.
9.2.4Install an empty sample vessel and perform a leak test of the system. Close the carrier gas valve and atmospheric vent and evacuate the sample vessel to 250 mm (10 in.) Hg absolute or less using the aspirator. Close the toggle valve at the inlet to the aspirator and observe the vacuum for at least 1 minute. If there is any change in the sample pressure, release the vacuum, adjust or repair the apparatus as necessary, and repeat the leak test.
9.2.5Perform the analyzer calibration and linearity checks according to the procedure in section 5.1. Record the responses to each of the calibration gases and the back-pressure setting of the FIA.
9.2.6Establish the appropriate dilution ratio by adjusting the aspirator air supply or substituting critical orifices. Operate the aspirator at a vacuum of at least 25 mm (1 in.) Hg greater than the vacuum necessary to achieve critical flow. Select the dilution ratio so that the maximum response of the FIA to the sample does not exceed the high-range calibration gas.
9.2.7Perform system calibration checks at two levels by introducing compressed gases at the inlet to the sample vessel while the aspirator and dilution devices are operating. Perform these checks using the carrier gas (zero concentration) and the system calibration gas. If the response to the carrier gas exceeds
9.2.8After completing the above checks, inject the system calibration gas for approximately 10 minutes. Time the exact duration of the gas injection using a stopwatch. Determine the area under the FIA response curve and calculate the system response factor based on the sample gas flow rate, gas concentration, and the duration of the injection as compared to the integrated response using Equations 204A-2 and 204A-3.
9.2.9Verify that the sample oven and sample line temperatures are 120
9.2.10Fill a tared syringe with approximately 1 g of the VOC containing liquid and weigh it. Transfer the liquid to a tared sample vessel. Plug the sample vessel to minimize sample loss. Weigh the sample vessel containing the liquid to determine the amount of sample actually received. Also, as a quality control check, weigh the empty syringe to determine the amount of material delivered. The two coating sample weights should agree within 0.02 g. If not, repeat the procedure until an acceptable sample is obtained.
9.2.11Connect the vessel to the analysis system. Adjust the aspirator supply pressure to the correct value. Open the valve on the carrier gas supply to the sample vessel and adjust it to provide a slight excess flow to the atmospheric vent. As soon as the initial response of the FIA begins to decrease, immerse the sample vessel in the water bath. (Applying heat to the sample vessel too soon may cause the FIA response to exceed the calibrated range of the instrument and, thus, invalidate the analysis.)
9.2.12Continuously measure and record the response of the FIA until all of the volatile material has been evaporated from the sample and the instrument response has returned to the baseline (i.e., response less than 0.5 percent of the span value). Observe the aspirator supply pressure, FIA back-pressure, atmospheric vent, and other system operating parameters during the run; repeat the analysis procedure if any of these parameters deviate from the values established during the system calibration checks in section 9.2.7. After each sample, perform the drift check described in section 8.2. If the drift check results are acceptable, calculate the VOC content of the sample using the equations in section 11.2. Alternatively, recalibrate the FIA as in section 8.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. Integrate the area under the FIA response curve, or determine the average concentration response and the duration of sample analysis.
10.1Nomenclature.
10.2Calculations
10.2.1Total VOC Content of the Input VOC Containing Liquid.
10.2.2Liquid Sample Analysis System Response Factor for Systems Using Integrators, Grams/Area Count.
10.2.3VOC Content of the Liquid Sample.
The measurement uncertainties are estimated for each VOC containing liquid as follows: W =
1.1Applicability. This procedure is applicable for determining the volatile organic compounds (VOC) content of captured gas streams. It is intended to be used in the development of a gas/gas protocol for determining VOC capture efficiency (CE) for surface coating and printing operations. The procedure may not be acceptable in certain site-specific situations [e.g., when: (1) direct-fired heaters or other circumstances affect the quantity of VOC at the control device inlet; and (2) particulate organic aerosols are formed in the process and are present in the captured emissions].
1.2Principle. The amount of VOC captured (G) is calculated as the sum of the products of the VOC content (C
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
A gas sample is extracted from the source though a heated sample line and, if necessary, a glass fiber filter to a flame ionization analyzer (FIA).
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Gas VOC Concentration. A schematic of the measurement system is shown in Figure 204B-1. The main components are as follows:
4.1.1Sample Probe. Stainless steel or equivalent. The probe shall be heated to prevent VOC condensation.
4.1.2Calibration Valve Assembly. Three-way valve assembly at the outlet of the sample probe to direct the zero and calibration gases to the analyzer. Other methods, such as quick-connect lines, to route calibration gases to the outlet of the sample probe are acceptable.
4.1.3Sample Line. Stainless steel or Teflon tubing to transport the sample gas to the analyzer. The sample line must be heated to prevent condensation.
4.1.4Sample Pump. A leak-free pump, to pull the sample gas through the system at a flow rate sufficient to minimize the response time of the measurement system. The components of the pump that contact the gas stream shall be constructed of stainless steel or Teflon. The sample pump must be heated to prevent condensation.
4.1.5Sample Flow Rate Control. A sample flow rate control valve and rotameter, or equivalent, to maintain a constant sampling rate within 10 percent. The flow rate control valve and rotameter must be heated to prevent condensation. A control valve may also be located on the sample pump bypass loop to assist in controlling the sample pressure and flow rate.
4.1.6Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated to the Administrator's satisfaction that they would provide equally accurate measurements. The system shall be capable of meeting or exceeding the following specifications:
4.1.6.1Zero Drift. Less than
4.1.6.2Calibration Drift. Less than
4.1.6.3Calibration Error. Less than
4.1.6.4Response Time. Less than 30 seconds.
4.1.7Integrator/Data Acquisition System. An analog or digital device, or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is one measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.
4.2Captured Emissions Volumetric Flow Rate.
4.2.1Method 2 or 2A Apparatus. For determining volumetric flow rate.
4.2.2Method 3 Apparatus and Reagents. For determining molecular weight of the gas stream. An estimate of the molecular weight of the gas stream may be used if approved by the Administrator.
4.2.3Method 4 Apparatus and Reagents. For determining moisture content, if necessary.
5.1Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.1.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H
5.1.2Carrier Gas. High purity air with less than 1 ppm of organic material (as propane or carbon equivalent) or less than 0.1 percent of the span value, whichever is greater.
5.1.3FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentrations of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown to the Administrator's satisfaction that equally accurate measurements would be achieved.
5.2Particulate Filter. An in-stack or an out-of-stack glass fiber filter is recommended if exhaust gas particulate loading is significant. An out-of-stack filter must be heated to prevent any condensation unless it can be demonstrated that no condensation occurs.
6.1Required instrument quality control parameters are found in the following sections:
6.1.1The FIA system must be calibrated as specified in section 7.1.
6.1.2The system drift check must be performed as specified in section 7.2.
6.1.3The system check must be conducted as specified in section 7.3.
6.2Audits.
6.2.1Analysis Audit Procedure. Immediately before each test, analyze an audit cylinder as described in section 7.2. The analysis audit must agree with the audit cylinder concentration within 10 percent.
6.2.2Audit Samples and Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B), Quality Assurance Division, Atmospheric Research and Exposure Assessment Labortory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 or by calling the STAC at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis.
6.2.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
7.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero-and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low- and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all four gases are within 5 percent of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system.
7.2Systems Drift Checks. Select the calibration gas that most closely approximates the concentration of the captured emissions for conducting the drift checks. Introduce the zero and calibration gases at the calibration valve assembly and verify that the appropriate gas flow rate and pressure are present at the FIA. Record the measurement system responses to the zero and calibration gases. The performance of the system is acceptable if the difference between the drift check measurement and the value obtained in section 7.1 is less than 3 percent of the span value. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value
7.3System Check. Inject the high-range calibration gas at the inlet of the sampling probe and record the response. The performance of the system is acceptable if the measurement system response is within 5 percent of the value obtained in section 7.1 for the high-range calibration gas. Conduct a system check before and after each test run.
8.1.Determination of Volumetric Flow Rate of Captured Emissions.
8.1.1Locate all points where emissions are captured from the affected facility. Using Method 1, determine the sampling points. Be sure to check each site for cyclonic or swirling flow.
8.1.2Measure the velocity at each sampling site at least once every hour during each sampling run using Method 2 or 2A.
8.2Determination of VOC Content of Captured Emissions.
8.2.1Analysis Duration. Measure the VOC responses at each captured emissions point during the entire test run or, if applicable, while the process is operating. If there are multiple captured emission locations, design a sampling system to allow a single FIA to be used to determine the VOC responses at all sampling locations.
8.2.2Gas VOC Concentration.
8.2.2.1Assemble the sample train as shown in Figure 204B-1. Calibrate the FIA according to the procedure in section 7.1.
8.2.2.2Conduct a system check according to the procedure in section 7.3.
8.2.2.3Install the sample probe so that the probe is centrally located in the stack, pipe, or duct, and is sealed tightly at the stack port connection.
8.2.2.4Inject zero gas at the calibration valve assembly. Allow the measurement system response to reach zero. Measure the system response time as the time required for the system to reach the effluent concentration after the calibration valve has been returned to the effluent sampling position.
8.2.2.5Conduct a system check before, and a system drift check after, each sampling run according to the procedures in sections 7.2 and 7.3. If the drift check following a run indicates unacceptable performance (see section 7.3), the run is not valid. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. The tester may elect to perform system drift checks during the run not to exceed one drift check per hour.
8.2.2.6Verify that the sample lines, filter, and pump temperatures are 120
8.2.2.7Begin sampling at the start of the test period and continue to sample during the entire run. Record the starting and ending times and any required process information as appropriate. If multiple captured emission locations are sampled using a single FIA, sample at each location for the same amount of time (e.g., 2 minutes) and continue to switch from one location to another for the entire test run. Be sure that total sampling time at each location is the same at the end of the test run. Collect at least four separate measurements from each sample point during each hour of testing. Disregard the measurements at each sampling location until two times the response time of the measurement system has elapsed. Continue sampling for at least 1 minute and record the concentration measurements.
8.2.3Background Concentration.
Not applicable when the building is used as the temporary total enclosure (TTE).
8.2.3.1Locate all natural draft openings (NDO's) of the TTE. A sampling point shall be at the center of each NDO, unless otherwise specified by the Administrator. If there are more than six NDO's, choose six sampling points evenly spaced among the NDO's.
8.2.3.2Assemble the sample train as shown in Figure 204B-2. Calibrate the FIA and conduct a system check according to the procedures in sections 7.1 and 7.3.
This sample train shall be separate from the sample train used to measure the captured emissions.
8.2.3.3Position the probe at the sampling location.
8.2.3.4Determine the response time, conduct the system check, and sample according to the procedures described in sections 8.2.2.4 through 8.2.2.7.
8.2.4Alternative Procedure. The direct interface sampling and analysis procedure described in section 7.2 of Method 18 may be used to determine the gas VOC concentration. The system must be designed to collect and analyze at least one sample every 10 minutes. If the alternative procedure is used to determine the VOC concentration of the captured emissions, it must also be used to determine the VOC concentration of the uncaptured emissions.
9.1Nomenclature.
9.2Calculations.
9.2.1Total VOC Captured Emissions.
9.2.2VOC Concentration of the Captured Emissions at Point j.
9.2.3Background VOC Concentration at Point i.
9.2.4Average Background Concentration.
If the concentration at each point is within 20 percent of the average concentration of all points, then use the arithmetic average.
The measurement uncertainties are estimated for each captured or uncaptured emissions point as follows: Q
1.1Applicability. This procedure is applicable for determining the volatile organic compounds (VOC) content of captured gas streams. It is intended to be used in the development of a gas/gas protocol in which uncaptured emissions are also measured for determining VOC capture efficiency (CE) for surface coating and printing operations. A dilution system is used to reduce the VOC concentration of the captured emissions to about the same concentration as the uncaptured emissions. The procedure may not be acceptable in certain site-specific situations [e.g., when: (1) direct-fired heaters or other circumstances affect the quantity of VOC at the control device inlet; and (2) particulate organic aerosols are formed in the process and are present in the captured emissions].
1.2Principle. The amount of VOC captured (G) is calculated as the sum of the products of the VOC content (C
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
A gas sample is extracted from the source using an in-stack dilution probe through a heated sample line and, if necessary, a glass fiber filter to a flame ionization analyzer (FIA). The sample train contains a sample gas manifold which allows multiple points to be sampled using a single FIA.
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Gas VOC Concentration. A schematic of the measurement system is shown in Figure 204C-1. The main components are as follows:
4.1.1Dilution System. A Kipp in-stack dilution probe and controller or similar device may be used. The dilution rate may be changed by substituting different critical orifices or adjustments of the aspirator supply pressure. The dilution system shall be heated to prevent VOC condensation. Note: An out-of-stack dilution device may be used.
4.1.2Calibration Valve Assembly. Three-way valve assembly at the outlet of the sample probe to direct the zero and calibration gases to the analyzer. Other methods, such as quick-connect lines, to route calibration gases to the outlet of the sample probe are acceptable.
4.1.3Sample Line. Stainless steel or Teflon tubing to transport the sample gas to the analyzer. The sample line must be heated to prevent condensation.
4.1.4Sample Pump. A leak-free pump, to pull the sample gas through the system at a flow rate sufficient to minimize the response time of the measurement system. The components of the pump that contact the gas stream shall be constructed of stainless steel or Teflon. The sample pump must be heated to prevent condensation.
4.1.5Sample Flow Rate Control. A sample flow rate control valve and rotameter, or equivalent, to maintain a constant sampling rate within 10 percent. The flow control valve and rotameter must be heated to prevent condensation. A control valve may also be located on the sample pump bypass loop to assist in controlling the sample pressure and flow rate.
4.1.6Sample Gas Manifold. Capable of diverting a portion of the sample gas stream to the FIA, and the remainder to the bypass discharge vent. The manifold components shall be constructed of stainless steel or Teflon. If captured or uncaptured emissions are to be measured at multiple locations, the measurement system shall be designed to use separate sampling probes, lines, and pumps for each measurement location and a common sample gas manifold and FIA. The sample gas manifold and connecting lines to the FIA must be heated to prevent condensation.
Depending on the number of sampling points and their location, it may not be possible to use only one FIA. However to reduce the effect of calibration error, the number of FIA's used during a test should be keep as small as possible.
4.1.7Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated to the Administrator's satisfaction that they would provide equally accurate measurements. The system shall be capable of meeting or exceeding the following specifications:
4.1.7.1Zero Drift. Less than
4.1.7.2Calibration Drift. Less than
4.1.7.3Calibration Error. Less than
4.1.7.4Response Time. Less than 30 seconds.
4.1.8Integrator/Data Acquisition System. An analog or digital device or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is one measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.
4.2Captured Emissions Volumetric Flow Rate.
4.2.1Method 2 or 2A Apparatus. For determining volumetric flow rate.
4.2.2Method 3 Apparatus and Reagents. For determining molecular weight of the gas stream. An estimate of the molecular weight of the gas stream may be used if approved by the Administrator.
4.2.3Method 4 Apparatus and Reagents. For determining moisture content, if necessary.
5.1Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.1.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H
5.1.2 Carrier Gas and Dilution Air Supply. High purity air with less than 1 ppm of organic material (as propane or carbon equivalent), or less than 0.1 percent of the span value, whichever is greater.
5.1.3 FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentrations of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown to the Administrator's satisfaction that equally accurate measurements would be achieved.
5.1.4Dilution Check Gas. Gas mixture standard containing propane in air, approximately half the span value after dilution.
5.2Particulate Filter. An in-stack or an out-of-stack glass fiber filter is recommended if exhaust gas particulate loading is significant. An out-of-stack filter must be heated to prevent any condensation unless it can be demonstrated that no condensation occurs.
6.1Required instrument quality control parameters are found in the following sections:
6.1.1The FIA system must be calibrated as specified in section 7.1.
6.1.2The system drift check must be performed as specified in section 7.2.
6.1.3The dilution factor must be determined as specified in section 7.3.
6.1.4The system check must be conducted as specified in section 7.4.
6.2Audits.
6.2.1Analysis Audit Procedure. Immediately before each test, analyze an audit cylinder as described in section 7.2. The analysis audit must agree with the audit cylinder concentration within 10 percent.
6.2.2Audit Samples and Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B), Quality Assurance Division, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 or by calling the STAC at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis.
6.2.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
7.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system after the dilution system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero-and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low-and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all four gases are within 5 percent of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system.
7.2Systems Drift Checks. Select the calibration gas that most closely approximates the concentration of the diluted captured emissions for conducting the drift checks. Introduce the zero and calibration gases at the calibration valve assembly, and verify that the appropriate gas flow rate and pressure are present at the FIA. Record the measurement system responses to the zero and calibration gases. The performance of the system is acceptable if the difference between the drift check measurement and the value obtained in section 7.1 is less than 3 percent of the span value. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. Conduct the system drift check at the end of each run.
7.3Determination of Dilution Factor. Inject the dilution check gas into the measurement system before the dilution system and record the response. Calculate the dilution factor using Equation 204C-3.
7.4System Check. Inject the high-range calibration gas at the inlet to the sampling probe while the dilution air is turned off. Record the response. The performance of the system is acceptable if the measurement system response is within 5 percent of the value obtained in section 7.1 for the high-range calibration gas. Conduct a system check before and after each test run.
8.1Determination of Volumetric Flow Rate of Captured Emissions
8.1.1Locate all points where emissions are captured from the affected facility. Using Method 1, determine the sampling points. Be sure to check each site for cyclonic or swirling flow.
8.2.2Measure the velocity at each sampling site at least once every hour during each sampling run using Method 2 or 2A.
8.2Determination of VOC Content of Captured Emissions
8.2.1Analysis Duration. Measure the VOC responses at each captured emissions point during the entire test run or, if applicable, while the process is operating. If there are multiple captured emissions locations, design a sampling system to allow a single FIA to be used to determine the VOC responses at all sampling locations.
8.2.2Gas VOC Concentration.
8.2.2.1Assemble the sample train as shown in Figure 204C-1. Calibrate the FIA according to the procedure in section 7.1.
8.2.2.2Set the dilution ratio and determine the dilution factor according to the procedure in section 7.3.
8.2.2.3Conduct a system check according to the procedure in section 7.4.
8.2.2.4Install the sample probe so that the probe is centrally located in the stack, pipe, or duct, and is sealed tightly at the stack port connection.
8.2.2.5Inject zero gas at the calibration valve assembly. Measure the system response time as the time required for the system to reach the effluent concentration after the calibration valve has been returned to the effluent sampling position.
8.2.2.6Conduct a system check before, and a system drift check after, each sampling run according to the procedures in sections 7.2 and 7.4. If the drift check following a run indicates unacceptable performance (see section 7.4), the run is not valid. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. The tester may elect to perform system drift checks during the run not to exceed one drift check per hour.
8.2.2.7Verify that the sample lines, filter, and pump temperatures are 120
8.2.2.8Begin sampling at the start of the test period and continue to sample during the entire run. Record the starting and ending times and any required process information as appropriate. If multiple captured emission locations are sampled using a single FIA, sample at each location for the same amount of time (e.g., 2 min.) and continue to switch from one location to another for the entire test run. Be sure that total sampling time at each location is the same at the end of the test run. Collect at least four separate measurements from each sample point during each hour of testing. Disregard the measurements at each sampling
8.2.3 Background Concentration.
Not applicable when the building is used as the temporary total enclosure (TTE).
8.2.3.1Locate all natural draft openings (NDO's) of the TTE. A sampling point shall be at the center of each NDO, unless otherwise approved by the Administrator. If there are more than six NDO's, choose six sampling points evenly spaced among the NDO's.
8.2.3.2Assemble the sample train as shown in Figure 204C-2. Calibrate the FIA and conduct a system check according to the procedures in sections 7.1 and 7.4.
8.2.3.3Position the probe at the sampling location.
8.2.3.4Determine the response time, conduct the system check, and sample according to the procedures described in sections 8.2.2.4 through 8.2.2.8.
8.2.4Alternative Procedure. The direct interface sampling and analysis procedure described in section 7.2 of Method 18 may be used to determine the gas VOC concentration. The system must be designed to collect and analyze at least one sample every 10 minutes. If the alternative procedure is used to determine the VOC concentration of the captured emissions, it must also be used to determine the VOC concentration of the uncaptured emissions.
9.1Nomenclature.
9.2Calculations.
9.2.1Total VOC Captured Emissions.
9.2.2VOC Concentration of the Captured Emissions at Point j.
9.2.3Dilution Factor.
9.2.4Background VOC Concentration at Point i.
9.2.5Average Background Concentration.
If the concentration at each point is within 20 percent of the average concentration of all points, then use the arithmetic average.
The measurement uncertainties are estimated for each captured or uncaptured emissions point as follows: Q
1.1Applicability. This procedure is applicable for determining the uncaptured volatile organic compounds (VOC) emissions from a temporary total enclosure (TTE). It is intended to be used as a segment in the development of liquid/gas or gas/gas protocols for determining VOC capture efficiency (CE) for surface coating and printing operations.
1.2Principle. The amount of uncaptured VOC emissions (F) from the TTE is calculated as the sum of the products of the VOC content (C
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
A gas sample is extracted from the uncaptured exhaust duct of a TTE through a heated sample line and, if necessary, a glass fiber filter to a flame ionization analyzer (FIA).
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Gas VOC Concentration. A schematic of the measurement system is shown in Figure 204D-1. The main components are as follows:
4.1.1Sample Probe. Stainless steel or equivalent. The probe shall be heated to prevent VOC condensation.
4.1.2Calibration Valve Assembly. Three-way valve assembly at the outlet of the sample probe to direct the zero and calibration gases to the analyzer. Other methods, such as quick-connect lines, to route calibration gases to the outlet of the sample probe are acceptable.
4.1.3Sample Line. Stainless steel or Teflon tubing to transport the sample gas to the analyzer. The sample line must be heated to prevent condensation.
4.1.4Sample Pump. A leak-free pump, to pull the sample gas through the system at a flow rate sufficient to minimize the response time of the measurement system. The components of the pump that contact the gas stream shall be constructed of stainless steel or Teflon. The sample pump must be heated to prevent condensation.
4.1.5Sample Flow Rate Control. A sample flow rate control valve and rotameter, or equivalent, to maintain a constant sampling rate within 10 percent. The flow control valve and rotameter must be heated to prevent condensation. A control valve may also be located on the sample pump bypass loop to assist in controlling the sample pressure and flow rate.
4.1.6Sample Gas Manifold. Capable of diverting a portion of the sample gas stream to the FIA, and the remainder to the bypass discharge vent. The manifold components shall be constructed of stainless steel or Teflon. If emissions are to be measured at multiple locations, the measurement system shall be designed to use separate sampling probes, lines, and pumps for each measurement location and a common sample gas manifold and FIA. The sample gas manifold and connecting lines to the FIA must be heated to prevent condensation.
4.1.7Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated to the Administrator's satisfaction that they would provide more accurate measurements. The system shall be capable of meeting or exceeding the following specifications:
4.1.7.1Zero Drift. Less than
4.1.7.2Calibration Drift. Less than
4.1.7.3Calibration Error. Less than
4.1.7.4Response Time. Less than 30 seconds.
4.1.8Integrator/Data Acquisition System. An analog or digital device or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is one measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.
4.2Uncaptured Emissions Volumetric Flow Rate.
4.2.1Method 2 or 2A Apparatus. For determining volumetric flow rate.
4.2.2Method 3 Apparatus and Reagents. For determining molecular weight of the gas stream. An estimate of the molecular weight of the gas stream may be used if approved by the Administrator.
4.2.3Method 4 Apparatus and Reagents. For determining moisture content, if necessary.
4.3Temporary Total Enclosure. The criteria for designing an acceptable TTE are specified in Method 204.
5.1Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.1.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H
5.1.2Carrier Gas. High purity air with less than 1 ppm of organic material (as propane or carbon equivalent) or less than 0.1 percent of the span value, whichever is greater.
5.1.3FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentrations of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown to the Administrator's satisfaction that equally accurate measurements would be achieved.
5.2Particulate Filter. An in-stack or an out-of-stack glass fiber filter is recommended if exhaust gas particulate loading is significant. An out-of-stack filter must be heated to prevent any condensation unless it can be demonstrated that no condensation occurs.
6.1Required instrument quality control parameters are found in the following sections:
6.1.1The FIA system must be calibrated as specified in section 7.1.
6.1.2The system drift check must be performed as specified in section 7.2.
6.1.3The system check must be conducted as specified in section 7.3.
6.2Audits.
6.2.1Analysis Audit Procedure. Immediately before each test, analyze an audit cylinder as described in section 7.2. The analysis audit must agree with the audit cylinder concentration within 10 percent.
6.2.2Audit Samples and Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B) Quality Assurance Division, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 or by calling the STAC at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis.
6.2.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
7.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero-and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low-and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all four gases are within 5 percent of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system.
7.2Systems Drift Checks. Select the calibration gas concentration that most closely approximates that of the uncaptured gas emissions concentration to conduct the drift checks. Introduce the zero and calibration gases at the calibration valve assembly and verify that the appropriate gas flow rate and pressure are present at the FIA. Record the measurement system responses to the zero and calibration gases. The performance of the system is acceptable if the difference between the drift check measurement and the value obtained in section 7.1 is less than 3 percent of the span value. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the
7.3System Check. Inject the high-range calibration gas at the inlet of the sampling probe and record the response. The performance of the system is acceptable if the measurement system response is within 5 percent of the value obtained in section 7.1 for the high-range calibration gas. Conduct a system check before each test run.
8.1Determination of Volumetric Flow Rate of Uncaptured Emissions
8.1.1 Locate all points where uncaptured emissions are exhausted from the TTE. Using Method 1, determine the sampling points. Be sure to check each site for cyclonic or swirling flow.
8.1.2Measure the velocity at each sampling site at least once every hour during each sampling run using Method 2 or 2A.
8.2Determination of VOC Content of Uncaptured Emissions.
8.2.1Analysis Duration. Measure the VOC responses at each uncaptured emission point during the entire test run or, if applicable, while the process is operating. If there are multiple emission locations, design a sampling system to allow a single FIA to be used to determine the VOC responses at all sampling locations.
8.2.2Gas VOC Concentration.
8.2.2.1Assemble the sample train as shown in Figure 204D-1. Calibrate the FIA and conduct a system check according to the procedures in sections 7.1 and 7.3, respectively.
8.2.2.2Install the sample probe so that the probe is centrally located in the stack, pipe, or duct, and is sealed tightly at the stack port connection.
8.2.2.3Inject zero gas at the calibration valve assembly. Allow the measurement system response to reach zero. Measure the system response time as the time required for the system to reach the effluent concentration after the calibration valve has been returned to the effluent sampling position.
8.2.2.4Conduct a system check before, and a system drift check after, each sampling run according to the procedures in sections 7.2 and 7.3. If the drift check following a run indicates unacceptable performance (see section 7.3), the run is not valid. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. The tester may elect to perform system drift checks during the run not to exceed one drift check per hour.
8.2.2.5Verify that the sample lines, filter, and pump temperatures are 120
8.2.2.6Begin sampling at the start of the test period and continue to sample during the entire run. Record the starting and ending times and any required process information, as appropriate. If multiple emission locations are sampled using a single FIA, sample at each location for the same amount of time (e.g., 2 min.) and continue to switch from one location to another for the entire test run. Be sure that total sampling time at each location is the same at the end of the test run. Collect at least four separate measurements from each sample point during each hour of testing. Disregard the response measurements at each sampling location until 2 times the response time of the measurement system has elapsed. Continue sampling for at least 1 minute and record the concentration measurements.
8.2.3Background Concentration.
8.2.3.1Locate all natural draft openings (NDO's) of the TTE. A sampling point shall be at the center of each NDO, unless otherwise approved by the Administrator. If there are more than six NDO's, choose six sampling points evenly spaced among the NDO's.
8.2.3.2Assemble the sample train as shown in Figure 204D-2. Calibrate the FIA and conduct a system check according to the procedures in sections 7.1 and 7.3.
8.2.3.3Position the probe at the sampling location.
8.2.3.4Determine the response time, conduct the system check, and sample according to the procedures described in sections 8.2.2.3 through 8.2.2.6.
8.2.4Alternative Procedure. The direct interface sampling and analysis procedure described in section 7.2 of Method 18 may be used to determine the gas VOC concentration. The system must be designed to collect and analyze at least one sample every 10 minutes. If the alternative procedure is used to determine the VOC concentration of the uncaptured emissions in a gas/gas protocol, it must also be used to determine the VOC concentration of the captured emissions. If a tester wishes to conduct a liquid/gas protocol using a gas chromatograph, the tester must use Method 204F for the liquid steam. A gas chromatograph is not an acceptable alternative to the FIA in Method 204A.
9.1Nomenclature.
9.2Calculations.
9.2.1Total Uncaptured VOC Emissions.
9.2.2VOC Concentration of the Uncaptured Emissions at Point j.
9.2.3Background VOC Concentration at Point i.
9.2.4Average Background Concentration.
If the concentration at each point is within 20 percent of the average concentration of all points, use the arithmetic average.
The measurement uncertainties are estimated for each uncaptured emission point as follows: Q
1.1Applicability. This procedure is applicable for determining the uncaptured volatile organic compounds (VOC) emissions from a building enclosure (BE). It is intended to be used in the development of liquid/gas or gas/gas protocols for determining VOC capture efficiency (CE) for surface coating and printing operations.
1.2Principle. The total amount of uncaptured VOC emissions (F
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
A gas sample is extracted from the uncaptured exhaust duct of a BE through a heated sample line and, if necessary, a glass fiber filter to a flame ionization analyzer (FIA).
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Gas VOC Concentration. A schematic of the measurement system is shown in Figure 204E-1. The main components are as follows:
4.1.1Sample Probe. Stainless steel or equivalent. The probe shall be heated to prevent VOC condensation.
4.1.2Calibration Valve Assembly. Three-way valve assembly at the outlet of the sample probe to direct the zero and calibration gases to the analyzer. Other methods, such as quick-connect lines, to route calibration gases to the outlet of the sample probe are acceptable.
4.1.3Sample Line. Stainless steel or Teflon tubing to transport the sample gas to the analyzer. The sample line must be heated to prevent condensation.
4.1.4Sample Pump. A leak-free pump, to pull the sample gas through the system at a flow rate sufficient to minimize the response time of the measurement system. The components of the pump that contact the gas stream shall be constructed of stainless steel or Teflon. The sample pump must be heated to prevent condensation.
4.1.5Sample Flow Rate Control. A sample flow rate control valve and rotameter, or equivalent, to maintain a constant sampling rate within 10 percent. The flow rate control valve and rotameter must be heated to prevent condensation. A control valve may also be located on the sample pump bypass loop to assist in controlling the sample pressure and flow rate.
4.1.6Sample Gas Manifold. Capable of diverting a portion of the sample gas stream to the FIA, and the remainder to the bypass discharge vent. The manifold components shall be constructed of stainless steel or Teflon. If emissions are to be measured at multiple locations, the measurement system shall be designed to use separate sampling probes, lines, and pumps for each measurement location, and a common sample gas manifold and FIA. The sample gas manifold must be heated to prevent condensation.
4.1.7Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated to the Administrator's satisfaction that they would provide equally accurate measurements. The system shall be capable of meeting or exceeding the following specifications:
4.1.7.1Zero Drift. Less than
4.1.7.2Calibration Drift. Less than
4.1.7.3Calibration Error. Less than
4.1.7.4Response Time. Less than 30 seconds.
4.1.8Integrator/Data Acquisition System. An analog or digital device or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is one measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.
4.2Uncaptured Emissions Volumetric Flow Rate.
4.2.1Flow Direction Indicators. Any means of indicating inward or outward flow, such as light plastic film or paper streamers, smoke tubes, filaments, and sensory perception.
4.2.2Method 2 or 2A Apparatus. For determining volumetric flow rate. Anemometers or similar devices calibrated according to the manufacturer's instructions may be used
4.2.3 Method 3 Apparatus and Reagents. For determining molecular weight of the gas stream. An estimate of the molecular weight of the gas stream may be used if approved by the Administrator.
4.2.4Method 4 Apparatus and Reagents. For determining moisture content, if necessary.
4.3Building Enclosure. The criteria for an acceptable BE are specified in Method 204.
5.1Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.1.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H
5.1.2Carrier Gas. High purity air with less than 1 ppm of organic material (propane or carbon equivalent) or less than 0.1 percent of the span value, whichever is greater.
5.1.3FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentrations of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown to the Administrator's satisfaction that equally accurate measurements would be achieved.
5.2Particulate Filter. An in-stack or an out-of-stack glass fiber filter is recommended if exhaust gas particulate loading is significant. An out-of-stack filter must be heated to prevent any condensation unless it can be demonstrated that no condensation occurs.
6.1Required instrument quality control parameters are found in the following sections:
6.1.1The FIA system must be calibrated as specified in section 7.1.
6.1.2The system drift check must be performed as specified in section 7.2.
6.1.3The system check must be conducted as specified in section 7.3.
6.2Audits.
6.2.1Analysis Audit Procedure. Immediately before each test, analyze an audit cylinder as described in section 7.2. The analysis audit must agree with the audit cylinder concentration within 10 percent.
6.2.2Audit Samples and Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B), Quality Assurance Division, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 or by calling the STAC at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis.
6.2.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
7.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero-and the high-range calibration gases, and adjust the analyzer calibration to provide the proper responses. Inject the low-and mid-range gases and record the responses of the measurement system. The
7.2Systems Drift Checks. Select the calibration gas that most closely approximates the concentration of the captured emissions for conducting the drift checks. Introduce the zero and calibration gases at the calibration valve assembly and verify that the appropriate gas flow rate and pressure are present at the FIA. Record the measurement system responses to the zero and calibration gases. The performance of the system is acceptable if the difference between the drift check measurement and the value obtained in section 7.1 is less than 3 percent of the span value. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. Conduct a system drift check at the end of each run.
7.3System Check. Inject the high-range calibration gas at the inlet of the sampling probe and record the response. The performance of the system is acceptable if the measurement system response is within 5 percent of the value obtained in section 7.1 for the high-range calibration gas. Conduct a system check before each test run.
8.1Preliminary Determinations. The following points are considered exhaust points and should be measured for volumetric flow rates and VOC concentrations:
8.1.1Forced Draft Openings. Any opening in the facility with an exhaust fan. Determine the volumetric flow rate according to Method 2.
8.1.2Roof Openings. Any openings in the roof of a facility which does not contain fans are considered to be exhaust points. Determine volumetric flow rate from these openings. Use the appropriate velocity measurement devices (e.g., propeller anemometers).
8.2Determination of Flow Rates.
8.2.1Measure the volumetric flow rate at all locations identified as exhaust points in section 8.1. Divide each exhaust opening into nine equal areas for rectangular openings and into eight equal areas for circular openings.
8.2.2Measure the velocity at each site at least once every hour during each sampling run using Method 2 or 2A, if applicable, or using the low velocity instruments in section 4.2.2.
8.3 Determination of VOC Content of Uncaptured Emissions.
8.3.1Analysis Duration. Measure the VOC responses at each uncaptured emissions point during the entire test run or, if applicable, while the process is operating. If there are multiple emissions locations, design a sampling system to allow a single FIA to be used to determine the VOC responses at all sampling locations.
8.3.2Gas VOC Concentration.
8.3.2.1Assemble the sample train as shown in Figure 204E-1. Calibrate the FIA and conduct a system check according to the procedures in sections 7.1 and 7.3, respectively.
8.3.2.2Install the sample probe so that the probe is centrally located in the stack, pipe, or duct, and is sealed tightly at the stack port connection.
8.3.2.3Inject zero gas at the calibration valve assembly. Allow the measurement system response to reach zero. Measure the system response time as the time required for the system to reach the effluent concentration after the calibration valve has been returned to the effluent sampling position.
8.3.2.4Conduct a system check before, and a system drift check after, each sampling run according to the procedures in sections 7.2 and 7.3. If the drift check following a run indicates unacceptable performance (see section 7.3), the run is not valid. Alternatively, recalibrate the FIA as in section 7.1 and report the results using both sets of calibration data (i.e., data determined prior to the test period and data determined following the test period). The data that results in the lowest CE value shall be reported as the results for the test run. The tester may elect to perform drift checks during the run, not to exceed one drift check per hour.
8.3.2.5Verify that the sample lines, filter, and pump temperatures are 120
8.3.2.6Begin sampling at the start of the test period and continue to sample during the entire run. Record the starting and ending times, and any required process information, as appropriate. If multiple emission locations are sampled using a single FIA, sample at each location for the same amount of time (e.g., 2 minutes) and continue to switch from one location to another for the entire test run. Be sure that total sampling time at each location is the same at the end of the test run. Collect at least four separate measurements from each sample point during each hour of testing. Disregard the response measurements at each sampling location until 2 times the response time of the measurement system has elapsed. Continue sampling for at least 1 minute, and record the concentration measurements.
8.4Alternative Procedure. The direct interface sampling and analysis procedure described in section 7.2 of Method 18 may be
9.1Nomenclature.
9.2Calculations
9.2.1Total VOC Uncaptured Emissions from the Building.
9.2.2VOC Concentration of the Uncaptured Emissions at Point j.
The measurement uncertainties are estimated for each uncaptured emissions point as follows: Q
1.1Applicability. This procedure is applicable for determining the input of volatile organic compounds (VOC). It is intended to be used as a segment in the development of liquid/gas protocols for determining VOC capture efficiency (CE) for surface coating and printing operations.
1.2Principle. The amount of VOC introduced to the process (L) is the sum of the products of the weight (W) of each VOC containing liquid (ink, paint, solvent, etc.) used,
1.3Sampling Requirements. A CE test shall consist of at least three sampling runs. Each run shall cover at least one complete production cycle, but shall be at least 3 hours long. The sampling time for each run need not exceed 8 hours, even if the production cycle has not been completed. Alternative sampling times may be used with the approval of the Administrator.
A sample of each coating used is distilled to separate the VOC fraction. The distillate is used to prepare a known standard for analysis by an flame ionization analyzer (FIA), calibrated against propane, to determine its RF.
Because this procedure is often applied in highly explosive areas, caution and care should be exercised in choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute endorsement. All gas concentrations (percent, ppm) are by volume, unless otherwise noted.
4.1Liquid Weight.
4.1.1Balances/Digital Scales. To weigh drums of VOC containing liquids to within 0.2 lb or 1.0 percent of the total weight of VOC liquid used.
4.1.2 Volume Measurement Apparatus (Alternative). Volume meters, flow meters, density measurement equipment, etc., as needed to achieve the same accuracy as direct weight measurements.
4.2 Response Factor Determination (FIA Technique). The VOC distillation system and Tedlar gas bag generation system apparatuses are shown in Figures 204F-1 and 204F-2, respectively. The following equipment is required:
4.2.1Sample Collection Can. An appropriately-sized metal can to be used to collect VOC containing materials. The can must be constructed in such a way that it can be grounded to the coating container.
4.2.2Needle Valves. To control gas flow.
4.2.3Regulators. For calibration, dilution, and sweep gas cylinders.
4.2.4Tubing and Fittings. Teflon and stainless steel tubing and fittings with diameters, lengths, and sizes determined by the connection requirements of the equipment.
4.2.5Thermometer. Capable of measuring the temperature of the hot water and oil baths to within 1 °C.
4.2.6Analytical Balance. To measure
4.2.7Microliter Syringe. 10-μl size.
4.2.8Vacuum Gauge or Manometer. 0- to 760-mm (0- to 30-in.) Hg U-Tube manometer or vacuum gauge.
4.2.9Hot Oil Bath, With Stirring Hot Plate. Capable of heating and maintaining a distillation vessel at 110
4.2.10Ice Water Bath. To cool the distillation flask.
4.2.11Vacuum/Water Aspirator. A device capable of drawing a vacuum to within 20 mm Hg from absolute.
4.2.12Rotary Evaporator System. Complete with folded inner coil, vertical style condenser, rotary speed control, and Teflon sweep gas delivery tube with valved inlet. Buchi Rotavapor or equivalent.
4.2.13Ethylene Glycol Cooling/Circulating Bath. Capable of maintaining the condenser coil fluid at −10 °C.
4.2.14Dry Gas Meter (DGM). Capable of measuring the dilution gas volume within 2 percent, calibrated with a spirometer or bubble meter, and equipped with a temperature gauge capable of measuring temperature within 3 °C.
4.2.15Activated Charcoal/Mole Sieve Trap. To remove any trace level of organics picked up from the DGM.
4.2.16Gas Coil Heater. Sufficient length of 0.125-inch stainless steel tubing to allow heating of the dilution gas to near the water bath temperature before entering the volatilization vessel.
4.2.17Water Bath, With Stirring Hot Plate. Capable of heating and maintaining a volatilization vessel and coil heater at a temperature of 100
4.2.18Volatilization Vessel. 50-ml midget impinger fitted with a septum top and loosely filled with glass wool to increase the volatilization surface.
4.2.19Tedlar Gas Bag. Capable of holding 30 liters of gas, flushed clean with zero air, leak tested, and evacuated.
4.2.20Organic Concentration Analyzer. An FIA with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated that they would provide equally accurate measurements. The FIA instrument should be the same instrument used in the gaseous analyses adjusted with the same fuel, combustion air, and sample back-pressure (flow rate) settings. The system shall be capable of meeting or exceeding the following specifications:
4.2.20.1Zero Drift. Less than
4.2.20.2Calibration Drift. Less than
4.2.20.3Calibration Error. Less than
4.2.21Integrator/Data Acquisition System. An analog or digital device or computerized data acquisition system used to integrate the FIA response or compute the average response and record measurement data.
4.2.22Chart Recorder (Optional). A chart recorder or similar device is recommended to provide a continuous analog display of the measurement results during the liquid sample analysis.
5.1Zero Air. High purity air with less than 1 ppm of organic material (as propane) or less than 0.1 percent of the span value, whichever is greater. Used to supply dilution air for making the Tedlar bag gas samples.
5.2THC Free N
5.3Calibration and Other Gases. Gases used for calibration, fuel, and combustion air (if required) are contained in compressed gas cylinders. All calibration gases shall be traceable to National Institute of Standards and Technology standards and shall be certified by the manufacturer to
5.3.1Fuel. The FIA manufacturer's recommended fuel should be used. A 40 percent H
5.3.2Combustion Air. High purity air with less than 1 ppm of organic material (as propane) or less than 0.1 percent of the span value, whichever is greater.
5.3.3FIA Linearity Calibration Gases. Low-, mid-, and high-range gas mixture standards with nominal propane concentration of 20-30, 45-55, and 70-80 percent of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown that equally accurate measurements would be achieved.
5.3.4System Calibration Gas. Gas mixture standard containing propane in air, approximating the VOC concentration expected for the Tedlar gas bag samples.
6.1Required instrument quality control parameters are found in the following sections:
6.1.1The FIA system must be calibrated as specified in section 7.1.
6.1.2The system drift check must be performed as specified in section 7.2.
6.2Precision Control. A minimum of one sample in each batch must be distilled and analyzed in duplicate as a precision control. If the results of the two analyses differ by more than
6.3Audits.
6.3.1Audit Procedure. Concurrently, analyze the audit sample and a set of compliance samples in the same manner to evaluate the technique of the analyst and the standards preparation. The same analyst, analytical reagents, and analytical system shall be used both for compliance samples and the EPA audit sample. If this condition is met, auditing of subsequent compliance analyses for the same enforcement agency within 30 days is not required. An audit sample set may not be used to validate different sets of compliance samples under the jurisdiction of different enforcement agencies, unless prior arrangements are made with both enforcement agencies.
6.3.2Audit Samples. Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (STAC) (MD-77B), Quality Assurance Division, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 or by calling the STAC at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis.
6.3.3Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency, and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency.
7.1FIA Calibration and Linearity Check. Make necessary adjustments to the air and fuel supplies for the FIA and ignite the burner. Allow the FIA to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero-and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low-and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all four gases are within 5 percent of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system. A calibration curve consisting of zero gas and two calibration levels must be performed at the beginning and end of each batch of samples.
7.2Systems Drift Checks. After each sample, repeat the system calibration checks in section 7.1 before any adjustments to the FIA or measurement system are made. If the zero or calibration drift exceeds
8.1Determination of Liquid Input Weight
8.1.1Weight Difference. Determine the amount of material introduced to the process as the weight difference of the feed material before and after each sampling run. In determining the total VOC containing liquid usage, account for: (a) The initial (beginning) VOC containing liquid mixture; (b) any solvent added during the test run; (c) any coating added during the test run; and (d) any residual VOC containing liquid mixture remaining at the end of the sample run.
8.1.1.1Identify all points where VOC containing liquids are introduced to the process. To obtain an accurate measurement of VOC containing liquids, start with an empty fountain (if applicable). After completing the run, drain the liquid in the fountain back into the liquid drum (if possible), and weigh the drum again. Weigh the VOC containing liquids to
8.1.1.2If it is not possible to measure a single representative mixture, then weigh the various components separately (e.g., if solvent is added during the sampling run, weigh the solvent before it is added to the mixture). If a fresh drum of VOC containing liquid is needed during the run, then weigh both the empty drum and fresh drum.
8.1.2Volume Measurement (Alternative). If direct weight measurements are not feasible, the tester may use volume meters and flow rate meters (and density measurements) to determine the weight of liquids used if it can be demonstrated that the technique produces results equivalent to the direct weight measurements. If a single representative mixture cannot be measured, measure the components separately.
8.2Determination of VOC Content in Input Liquids
8.2.1Collection of Liquid Samples.
8.2.1.1Collect a 1-pint or larger sample of the VOC containing liquid mixture at each application location at the beginning and end of each test run. A separate sample should be taken of each VOC containing liquid added to the application mixture during the test run. If a fresh drum is needed during the sampling run, then obtain a sample from the fresh drum.
8.2.1.2When collecting the sample, ground the sample container to the coating drum. Fill the sample container as close to the rim as possible to minimize the amount of headspace.
8.2.1.3After the sample is collected, seal the container so the sample cannot leak out or evaporate.
8.2.1.4Label the container to identify clearly the contents.
8.2.2Distillation of VOC.
8.2.2.1Assemble the rotary evaporator as shown in Figure 204F-1.
8.2.2.2Leak check the rotary evaporation system by aspirating a vacuum of approximately 20 mm Hg from absolute. Close up the system and monitor the vacuum for approximately 1 minute. If the vacuum falls more than 25 mm Hg in 1 minute, repair leaks and repeat. Turn off the aspirator and vent vacuum.
8.2.2.3Deposit approximately 20 ml of sample (inks, paints, etc.) into the rotary evaporation distillation flask.
8.2.2.4Install the distillation flask on the rotary evaporator.
8.2.2.5Immerse the distillate collection flask into the ice water bath.
8.2.2.6Start rotating the distillation flask at a speed of approximately 30 rpm.
8.2.2.7Begin heating the vessel at a rate of 2 to 3 °C per minute.
8.2.2.8After the hot oil bath has reached a temperature of 50 °C or pressure is evident on the mercury manometer, turn on the aspirator and gradually apply a vacuum to the evaporator to within 20 mm Hg of absolute. Care should be taken to prevent material burping from the distillation flask.
8.2.2.9Continue heating until a temperature of 110 °C is achieved and maintain this temperature for at least 2 minutes, or until the sample has dried in the distillation flask.
8.2.2.10Slowly introduce the N
8.2.2.11Continue sweeping the remaining solvent VOC from the distillation flask and condenser assembly for 2 minutes, or until all traces of condensed solvent are gone from the vessel. Some distillate may remain in the still head. This will not affect solvent recovery ratios.
8.2.2.12Release the vacuum, disassemble the apparatus and transfer the distillate to a labeled, sealed vial.
8.2.3Preparation of VOC standard bag sample.
8.2.3.1Assemble the bag sample generation system as shown in Figure 204F-2 and bring the water bath up to near boiling temperature.
8.2.3.2Inflate the Tedlar bag and perform a leak check on the bag.
8.2.3.3Evacuate the bag and close the bag inlet valve.
8.2.3.4Record the current barometric pressure.
8.2.3.5Record the starting reading on the dry gas meter, open the bag inlet valve, and start the dilution zero air flowing into the Tedlar bag at approximately 2 liters per minute.
8.2.3.6The bag sample VOC concentration should be similar to the gaseous VOC concentration measured in the gas streams. The amount of liquid VOC required can be approximated using equations in section 9.2. Using Equation 204F-4, calculate C
8.2.3.7Quickly withdraw an aliquot of the approximate amount calculated in section 8.2.3.6 from the distillate vial with the microliter syringe and record its weight from the analytical balance to the nearest 0.01 mg.
8.2.3.8Inject the contents of the syringe through the septum of the volatilization vessel into the glass wool inside the vessel.
8.2.3.9Reweigh and record the tare weight of the now empty syringe.
8.2.3.10Record the pressure and temperature of the dilution gas as it is passed through the dry gas meter.
8.2.3.11After approximately 20 liters of dilution gas have passed into the Tedlar bag, close the valve to the dilution air source and record the exact final reading on the dry gas meter.
8.2.3.12The gas bag is then analyzed by FIA within 1 hour of bag preparation in accordance with the procedure in section 8.2.4.
8.2.4Determination of VOC response factor.
8.2.4.1Start up the FIA instrument using the same settings as used for the gaseous VOC measurements.
8.2.4.2Perform the FIA analyzer calibration and linearity checks according to the procedure in section 7.1. Record the responses to each of the calibration gases and the back-pressure setting of the FIA.
8.2.4.3Connect the Tedlar bag sample to the FIA sample inlet and record the bag concentration in terms of propane. Continue the analyses until a steady reading is obtained for at least 30 seconds. Record the final reading and calculate the RF.
8.2.5Determination of coating VOC content as VOC (V
8.2.5.1Determine the VOC content of the coatings used in the process using EPA Method 24 or 24A as applicable.
9.1.Nomenclature.
9.2Calculations.
9.2.1Bag sample volume.
9.2.2Bag sample VOC concentration.
9.2.3Bag sample VOC concentration as propane.
9.2.4Response Factor.
9.2.5Total VOC Content of the Input VOC Containing Liquid.
1.1 Applicability. A gas dilution system can provide known values of calibration gases through controlled dilution of high-level calibration gases with an appropriate dilution gas. The instrumental test methods in 40 CFR part 60—e.g., Methods 3A, 6C, 7E, 10, 15, 16, 20, 25A and 25B—require on-site, multi-point calibration using gases of known concentrations. A gas dilution system that produces known low-level calibration gases from high-level calibration gases, with a degree of confidence similar to that for Protocol
1.2 Principle. The gas dilution system shall be evaluated on one analyzer once during each field test. A precalibrated analyzer is chosen, at the discretion of the source owner or operator, to demonstrate that the gas dilution system produces predictable gas concentrations spanning a range of concentrations. After meeting the requirements of this method, the remaining analyzers may be calibrated with the dilution system in accordance to the requirements of the applicable method for the duration of the field test. In Methods 15 and 16, 40 CFR part 60, appendix A, reactive compounds may be lost in the gas dilution system. Also, in Methods 25A and 25B, 40 CFR part 60, appendix A, calibration with target compounds other than propane is allowed. In these cases, a laboratory evaluation is required once per year in order to assure the Administrator that the system will dilute these reactive gases without significant loss.
The laboratory evaluation is required only if the source owner or operator plans to utilize the dilution system to prepare gases mentioned above as being reactive.
2.1 Gas Dilution System. The gas dilution system shall produce calibration gases whose measured values are within
2.1.1 The gas dilution system shall be recalibrated once per calendar year using NIST-traceable primary flow standards with an uncertainty ≤0.25 percent. A label shall be affixed at all times to the gas dilution system listing the date of the most recent calibration, the due date for the next calibration, and the person or manufacturer who carried out the calibration. Follow the manufacturer's instructions for the operation and use of the gas dilution system. A copy of the manufacturer's instructions for the operation of the instrument, as well as the most recent recalibration documentation shall be made available for the Administrator's inspection upon request.
2.1.2 Some manufacturers of mass flow controllers recommend that flow rates below 10 percent of flow controller capacity be avoided; check for this recommendation and follow the manufacturer's instructions. One study has indicated that silicone oil from a positive displacement pump produces an interference in SO
2.2 High-Level Supply Gas. An EPA Protocol calibration gas is recommended, due to its accuracy, as the high-level supply gas.
2.3 Mid-Level Supply Gas. An EPA Protocol gas shall be used as an independent check of the dilution system. The concentration of the mid-level supply gas shall be within 10 percent of one of the dilution levels tested in Section 3.2.
3.1 Laboratory Evaluation (Optional). If the gas dilution system is to be used to formulate calibration gases with reactive compounds (Test Methods 15, 16, and 25A/25B (only if using a calibration gas other than propane during the field test) in 40 CFR part 60, appendix A), a laboratory certification must be conducted once per calendar year for each reactive compound to be diluted. In the laboratory, carry out the procedures in Section 3.2 on the analyzer required in each respective test method to be laboratory certified (15, 16, or 25A and 25B for compounds other than propane). For each compound in which the gas dilution system meets the requirements in Section 3.2, the source must provide the laboratory certification data for the field test and in the test report.
3.2 Field Evaluation (Required). The gas dilution system shall be evaluated at the test site with an analyzer or monitor chosen by the source owner or operator. It is recommended that the source owner or operator choose a precalibrated instrument with a
3.2.1 Prepare the gas dilution system according to the manufacturer's instructions. Using the high-level supply gas, prepare, at a minimum, two dilutions within the range of each dilution device utilized in the dilution system (unless, as in critical orifice systems, each dilution device is used to make only one dilution; in that case, prepare one dilution for each dilution device). Dilution device in this method refers to each mass flow controller, critical orifice, capillary tube, positive displacement pump, or any other device which is used to achieve gas dilution.
3.2.2 Calculate the predicted concentration for each of the dilutions based on the flow rates through the gas dilution system (or the dilution ratios) and the certified concentration of the high-level supply gas.
3.2.3 Introduce each of the dilutions from Section 3.2.1 into the analyzer or monitor one at a time and determine the instrument response for each of the dilutions.
3.2.4 Repeat the procedure in Section 3.2.3 two times, i.e., until three injections are made at each dilution level. Calculate the average instrument response for each triplicate injection at each dilution level. No single injection shall differ by more than
3.2.5 For each level of dilution, calculate the difference between the average concentration output recorded by the analyzer and the predicted concentration calculated in Section 3.2.2. The average concentration output from the analyzer shall be within
3.2.6 Introduce the mid-level supply gas directly into the analyzer, bypassing the gas dilution system. Repeat the procedure twice more, for a total of three mid-level supply gas injections. Calculate the average analyzer output concentration for the mid-level supply gas. The difference between the certified concentration of the mid-level supply gas and the average instrument response shall be within
3.3 If the gas dilution system meets the criteria listed in Section 3.2, the gas dilution system may be used throughout that field test. If the gas dilution system fails any of the criteria listed in Section 3.2, and the tester corrects the problem with the gas dilution system, the procedure in Section 3.2 must be repeated in its entirety and all the criteria in Section 3.2 must be met in order for the gas dilution system to be utilized in the test.
1. “EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards,” EPA-600/R93/224, Revised September 1993.
1.0
1.1
1.1.1 Fossil fuel-fired steam generators, as specified in paragraph 2.1 of this appendix, shall be monitored for opacity, nitrogen oxides emissions, sulfur dioxide emissions, and oxygen or carbon dioxide.
1.1.2 Fluid bed catalytic cracking unit catalyst regenerators, as specified in paragraph 2.4 of this appendix, shall be monitored for opacity.
1.1.3 Sulfuric acid plants, as specified in paragraph 2.3 of this appendix, shall be monitored for sulfur dioxide emissions.
1.1.4 Nitric acid plants, as specified in paragraph 2.2 of this appendix, shall be monitored for nitrogen oxides emissions.
1.2
1.2.1 Subject to a new source performance standard promulgated in 40 CFR part 60 pursuant to section 111 of the Clean Air Act; or
1.2.2 not subject to an applicable emission standard of an approved plan; or
1.2.3 scheduled for retirement within 5 years after inclusion of monitoring requirements for the source in appendix P, provided that adequate evidence and guarantees are provided that clearly show that the source will cease operations prior to such date.
1.3
1.4
2.0
2.1
2.1.1 A continuous monitoring system for the measurement of opacity which meets the performance specifications of paragraph 3.1.1 of this appendix shall be installed, calibrated, maintained, and operated in accordance with the procedures of this appendix by the owner or operator of any such steam generator of greater than 250 million BTU per hour heat input except where:
2.1.1.1 gaseous fuel is the only fuel burned, or
2.1.1.2 oil or a mixture of gas and oil are the only fuels burned and the source is able to comply with the applicable particulate matter and opacity regulations without utilization of particulate matter collection equipment, and where the source has never been found, through any administrative or judicial proceedings, to be in violation of any visible emission standard of the applicable plan.
2.1.2 A continuous monitoring system for the measurement of sulfur dioxide which meets the performance specifications of paragraph 3.1.3 of this appendix shall be installed, calibrated, maintained, and operated on any fossil fuel-fired steam generator of greater than 250 million BTU per hour heat input which has installed sulfur dioxide pollutant control equipment.
2.1.3 A continuous monitoring system for the measurement of nitrogen oxides which meets the performance specification of paragraph 3.1.2 of this appendix shall be installed, calibrated, maintained, and operated on fossil fuel-fired steam generators of greater than 1000 million BTU per hour heat input when such facility is located in an Air Quality Control Region where the Administrator has specifically determined that a control strategy for nitrogen dioxide is necessary to attain the national standards, unless the source owner or operator demonstrates during source compliance tests as required by the State that such a source emits nitrogen oxides at levels 30 percent or more below the emission standard within the applicable plan.
2.1.4 A continuous monitoring system for the measurement of the percent oxygen or carbon dioxide which meets the performance specifications of paragraphs 3.1.4 or 3.1.5 of this appendix shall be installed, calibrated, operated, and maintained on fossil fuel-fired steam generators where measurements of oxygen or carbon dioxide in the flue gas are required to convert either sulfur dioxide or nitrogen oxides continuous emission monitoring data, or both, to units of the emission standard within the applicable plan.
2.2
2.3
2.4
3.0
3.1
3.1.1 Continuous monitoring systems for measuring opacity shall comply with Performance Specification 1.
3.1.2 Continuous monitoring systems for measuring nitrogen oxides shall comply with Performance Specification 2.
3.1.3 Continuous monitoring systems for measuring sulfur dioxide shall comply with Performance Specification 2.
3.1.4 Continuous monitoring systems for measuring oxygen shall comply with Performance Specification 3.
3.1.5 Continuous monitoring systems for measuring carbon dioxide shall comply with Performance Specification 3.
3.2
3.3
3.4
3.4.1 Continuous monitoring systems for measuring opacity shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 10-second period.
3.4.2 Continuous monitoring systems for measuring oxides of nitrogen, carbon dioxide, oxygen, or sulfur dioxide shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15-minute period.
3.5
3.6
3.7
3.8
3.9
3.9.1 Alternative monitoring requirements to accommodate continuous monitoring systems that require corrections for stack moisture conditions (e.g., an instrument measuring steam generator SO
3.9.2 Alternative locations for installing continuous monitoring systems or monitoring devices when the owner or operator can demonstrate that installation at alternative locations will enable accurate and representative measurements.
3.9.3 Alternative procedures for performing calibration checks (e.g., some instruments may demonstrate superior drift characteristics that require checking at less frequent intervals).
3.9.4 Alternative monitoring requirements when the effluent from one affected facility or the combined effluent from two or more identical affected facilities is released to the atmosphere through more than one point (e.g., an extractive, gaseous monitoring system used at several points may be approved if the procedures recommended are suitable for generating accurate emission averages).
3.9.5 Alternative continuous monitoring systems that do not meet the spectral response requirements in Performance Specification 1, appendix B of part 60, but adequately demonstrate a definite and consistent relationship between their measurements and the opacity measurements of a system complying with the requirements in Performance Specification 1. The State may require that such demonstration be performed for each affected facility.
4.0
4.1 The State plan shall require owners or operators of facilities required to install continuous monitoring systems to submit a written report of excess emissions for each calendar quarter and the nature and cause of the excess emissions, if known. The averaging period used for data reporting should be established by the State to correspond to the averaging period specified in the emission test method used to determine compliance with an emission standard for the pollutant/source category in question. The required report shall include, as a minimum, the data stipulated in this appendix.
4.2 For opacity measurements, the summary shall consist of the magnitude in actual percent opacity of all one-minute (or such other time period deemed appropriate by the State) averages of opacity greater than the opacity standard in the applicable plan for each hour of operation of the facility. Average values may be obtained by integration over the averaging period or by arithmetically averaging a minimum of four equally spaced, instantaneous opacity meas-ure-ments per minute. Any time period exempted shall be considered before determining the excess averages of opacity (e.g., whenever a regulation allows two minutes of opacity measurements in excess of the standard, the State shall require the source to report all opacity averages, in any one hour, in excess of the standard, minus the two-minute exemption). If more than one opacity standard applies, excess emissions data must be submitted in relation to all such standards.
4.3 For gaseous measurements the summary shall consist of emission averages, in the units of the applicable standard, for each averaging period during which the applicable standard was exceeded.
4.4 The date and time identifying each period during which the continuous monitoring system was inoperative, except for zero and
4.5 When no excess emissions have occurred and the continuous monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be included in the report.
4.6 The State plan shall require owners or operators of affected facilities to maintain a file of all information reported in the quarterly summaries, and all other data collected either by the continuous monitoring system or as necessary to convert monitoring data to the units of the applicable standard for a minimum of two years from the date of collection of such data or submission of such summaries.
5.0
5.1 For fossil fuel-fired steam generators the following procedures shall be used to convert gaseous emission monitoring data in parts per million to g/million cal (lb/million BTU) where necessary:
5.1.1 When the owner or operator of a fossil fuel-fired steam generator elects under paragraph 2.1.4 of this appendix to measure oxygen in the flue gases, the measurements of the pollutant concentration and oxygen concentration shall each be on a dry basis and the following conversion procedure used:
5.1.2 When the owner or operator elects under paragraph 2.1.4 of this appendix to measure carbon dioxide in the flue gases, the measurement of the pollutant concentration and the carbon dioxide concentration shall each be on a consistent basis (wet or dry) and the following conversion procedure used:
5.1.3 The values used in the equations under paragraph 5.1 are derived as follows:
5.2 For sulfuric acid plants the owner or operator shall:
5.2.1 establish a conversion factor three times daily according to the procedures to § 60.84(b) of this chapter;
5.2.2 multiply the conversion factor by the average sulfur dioxide concentration in the flue gases to obtain average sulfur dioxide emissions in Kg/metric ton (lb/short ton); and
5.2.3 report the average sulfur dioxide emission for each averaging period in excess of the applicable emission standard in the quarterly summary.
5.3 For nitric acid plants the owner or operator shall:
5.3.1 establish a conversion factor according to the procedures of § 60.73(b) of this chapter;
5.3.2 multiply the conversion factor by the average nitrogen oxides concentration in the flue gases to obtain the nitrogen oxides emissions in the units of the applicable standard;
5.3.3 report the average nitrogen oxides emission for each averaging period in excess of the applicable emission standard, in the quarterly summary.
5.4 Any State may allow data reporting or reduction procedures varying from those set forth in this appendix if the owner or operator of a source shows to the satisfaction of the State that his procedures are at least as accurate as those in this appendix. Such procedures may include but are not limited to, the following:
5.4.1 Alternative procedures for computing emission averages that do not require integration of data (e.g., some facilities may demonstrate that the variability of their emissions is sufficiently small to allow accurate reduction of data based upon computing averages from equally spaced data points over the averaging period).
5.4.2 Alternative methods of converting pollutant concentration measurements to the units of the emission standards.
6.0
6.1 Alternative monitoring requirements may be prescribed when installation of a continuous monitoring system or monitoring device specified by this appendix would not provide accurate determinations of emissions (e.g., condensed, uncombined water vapor may prevent an accurate determination of opacity using commercially available continuous monitoring systems).
6.2 Alternative monitoring requirements may be prescribed when the affected facility is infrequently operated (e.g., some affected facilities may operate less than one month per year).
6.3 Alternative monitoring requirements may be prescribed when the State determines that the requirements of this appendix would impose an extreme economic burden on the source owner or operator.
6.4 Alternative monitoring requirements may be prescribed when the State determines that monitoring systems prescribed by this appendix cannot be installed due to physical limitations at the facility.
This appendix sets forth EPA's Interpretative Ruling on the preconstruction review requirements for stationary sources of air pollution (not including indirect sources) under 40 CFR subpart I and section 129 of the Clean Air Act Amendments of 1977, Public Law 95-95, (note under 42 U.S.C. 7502). A major new source or major modification which would locate in an area designated in 40 CFR 81.300
For each area designated as exceeding an NAAQS (nonattainment area) under 40 CFR 81.300
The requirement of this Ruling shall not apply to any major stationary source or major modification that was not subject to the Ruling as in effect on January 16, 1979, if the owner or operator:
A. Obtained all final Federal, State, and local preconstruction approvals or permits necessary under the applicable State Implementation Plan before August 7, 1980;
B. Commenced construction within 18 months from August 7, 1980, or any earlier time required under the applicable State Implementation Plan; and
C. Did not discontinue construction for a period of 18 months or more and completed construction within a reasonable time.
A.
1.
2.
3.
4. (i)
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(ii) A major stationary source that is major for volatile organic compounds shall be considered major for ozone.
(iii) The fugitive emissions of a stationary source shall not be included in determining for any of the purposes of this ruling whether it is a major stationary source, unless the source belongs to one of the following categories of stationary sources:
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5. (i)
(ii) Any net emissions increase that is considered significant for volatile organic compounds shall be considered significant for ozone.
(iii) A physical change or change in the method of operation shall not include:
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6. (i)
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(ii) An increase or decrease in actual emissions is contemporaneous with the increase from the particular change only if it occurs between:
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(
(iii) An increase or decrease in actual emissions is creditable only if the Administrator has not relied on it in issuing a permit
(iv) An increase in actual emissions is creditable only to the extent that the new level of actual emissions exceeds the old level.
(v) A decrease in actual emissions is creditable only to the extent that:
(
(
(
(
(vi) An increase that results from a physical change at a source occurs when the emissions unit on which construction occurred becomes operational and begins to emit a particular pollutant. Any replacement unit that requires shakedown becomes operational only after a reasonable shakedown period, not to exceed 180 days.
7.
8.
9.
10. (i)
11.
(i) Applicable standards as set forth in 40 CFR parts 60 and 61;
(ii) Any applicable State Implementation Plan emissions limitation, including those with a future compliance date; or
(iii) The emissions rate specified as a federally enforceable permit condition, including those with a future compliance date.
12.
13. (i)
(ii) In general, actual emissions as of a particular date shall equal the average rate, in tons per year, at which the unit actually emitted the pollutant during a two-year period which precedes the particular date and which is representative of normal source operation. The reviewing authority shall allow the use of a different time period upon a determination that it is more representative of normal source operation. Actual emissions shall be calculated using the unit's actual operating hours, production rates, and types of materials processed, stored or combusted during the selected time period.
(iii) The reviewing authority may presume that source-specific allowable emissions for the unit are equivalent to the actual emissions of the unit.
(iv) For any emissions unit which has not begun normal operations on the particular date, actual emissions shall equal the potential to emit of the unit on that date.
14.
15.
(i) Begun, or caused to begin, a continuous program of actual on-site construction of the source, to be completed within a reasonable time; or
(ii) Entered into binding agreements or contractual obligations, which cannot be cancelled or modified without substantial loss to the owner or operator, to undertake a program of actual construction of the source to be completed within a reasonable time.
16.
17.
18.
(i) The most stringent emissions limitation which is contained in the implementation plan of any State for such class or category of stationary source, unless the owner or operator of the proposed stationary source demonstrates that such limitations are not achievable; or
(ii) The most stringent emissions limitation which is achieved in practice by such class or category of stationary source. This limitation, when applied to a modification, means the lowest achievable emissions rate for the new or modified emissions units within the stationary source. In no event shall the application of this term permit a proposed new or modified stationary source to emit any pollutant in excess of the amount allowable under applicable new source standards of performance.
19.
20.
B.
C.
D.-E. [Reserved]
F.
(1) Coal cleaning plants (with thermal dryers);
(2) Kraft pulp mills;
(3) Portland cement plants;
(4) Primary zinc smelters;
(5) Iron and steel mills;
(6) Primary aluminum ore reduction plants;
(7) Primary copper smelters;
(8) Municipal incinerators capable of charging more than 250 tons of refuse per day;
(9) Hydrofluoric, sulfuric, or nitric acid plants;
(10) Petroleum refineries;
(11) Lime plants;
(12) Phosphate rock processing plants;
(13) Coke oven batteries;
(14) Sulfur recovery plants;
(15) Carbon black plants (furnace process);
(16) Primary lead smelters;
(17) Fuel conversion plants;
(18) Sintering plants;
(19) Secondary metal production plants;
(20) Chemical process plants;
(21) Fossil-fuel boilers (or combination thereof) totaling more than 250 million British thermal units per hour heat input;
(22) Petroleum storage and transfer units with a total storage capacity exceeding 300,000 barrels;
(23) Taconite ore processing plants;
(24) Glass fiber processing plants;
(25) Charcoal production plants;
(26) Fossil fuel-fired steam electric plants of more than 250 million British thermal units per hour heat input;
(27) Any other stationary source category which, as of August 7, 1980, is being regulated under section 111 or 112 of the Act.
G.
A. This section applies only to major sources or major modifications which would locate in an area designated in 40 CFR 81.300
B. Sources to which this section applies must meet Conditions 1, 2, and 4 of Section IV.A. of this ruling.
C.
For sources of nitrogen oxides, the initial determination of whether a source would cause or contribute to a violation of the NAAQS for NO
For ozone, sources of volatile organic compounds, locating outside a designated ozone nonattainment area, will be presumed to have no significant impact on the designated nonattainment area. If ambient monitoring indicates that the area of source location is in fact nonattainment, then the source may be permitted under the provisions of any State plan adopted pursuant to section 110(a)(2)(D) of the Act until the area is designated nonattainment and a State Implementation Plan revision is approved. If no State plan pursuant to section 110(a)(2)(D) has been adopted and approved, then this Ruling shall apply.
As noted above, the determination as to whether a source would cause or contribute to a violation of an NAAQS should be made as of the new source's start-up date. Therefore, if a designated nonattainment area is projected to be an attainment area as part of an approved SIP control strategy by the new source start-up date, offsets would not be required if the new source would not cause a new violation.
D.
A.
Only intrapollutant emission offsets will be acceptable (e.g., hydrocarbon increases may not be offset against SO
B.
(i) Resource recovery facilities burning municipal solid waste, and (ii) sources which must switch fuels due to lack of adequate fuel supplies or where a source is required to be modified as a result of EPA regulations (e.g., lead-in-fuel requirements) and no exemption from such regulation is available to the source. Such an exemption may be granted only if:
1. The applicant demonstrates that it made its best efforts to obtain sufficient emission offsets to comply with Condition 1 under Section III or Conditions 3 and 4 under Section IV.A. and that such efforts were unsuccessful;
2. The applicant has secured all available emission offsets; and
3. The applicant will continue to seek the necessary emission offsets and apply them when they become available.
Such an exemption may result in the need to revise the SIP to provide additional control of existing sources.
Temporary emission sources, such as pilot plants, portable facilities which will be relocated outside of the nonattainment area after a short period of time, and emissions resulting from the construction phase of a new source, are exempt from Conditions 3 and 4 of this section.
C.
1.
Where the SIP emission limit allows greater emissions than the uncontrolled emission rate of the source (as when a State has a single particulate emission limit for all fuels), emission offset credit will be allowed only for control below the uncontrolled emission rate.
2.
3. (i)
A source may generally be credited with emissions reductions achieved by shutting down an existing source or permanently curtailing production or operating hours below baseline levels (see initial discussion in this Section IV.C), if such reductions are permanent, quantifiable, and federally enforceable, and if the area has an EPA-approved attainment plan. In addition, the shutdown or curtailment is creditable only if it occurred on or after the date specified for this purpose in the plan, and if such date is on or after the date of the most recent emissions inventory used in the plan's demonstration of attainment. Where the plan does not specify a cutoff date for shutdown credits, the date of the most recent emissions inventory or attainment demonstration, as the case may be, shall apply. However, in no event may credit be given for shutdowns which occurred prior to August 7, 1977. For purposes of this paragraph, a permitting authority may choose to consider a prior shutdown or curtailment to have occurred after the date of its most recent emissions inventory, if the inventory
(ii) Such reductions may be credited in the absence of an approved attainment demonstration only if the shutdown or curtailment occurred on or after the date the new source application is filed, or, if the applicant can establish that the proposed new source is a replacement for the shutdown or curtailed source and the cutoff date provisions of section IV.C.3.(i) are observed.
4.
5.
6.
D.
Offsets for NO
E.
F.
The necessary emission offsets may be proposed either by the owner of the proposed source or by the local community or the State. The emission reduction committed to must be enforceable by authorized State and/or local agencies and under the Clean Air Act, and must be accomplished by the new source's start-up date. If emission reductions are to be obtained in a State that neighbors the State in which the new source is to be located, the emission reductions committed to must be enforceable by the neighboring State and/or local agencies and under the Clean Air Act. Where the new facility is a replacement for a facility that is being shut down in order to provide the necessary offsets, the reviewing authority may allow up to 180 days for shakedown of the new facility before the existing facility is required to cease operation.
A.
(1) Reductions from sources controlled by the source owner (internal emission offsets); and/or (2) reductions from neighboring sources (external emission offsets). The source does not have to investigate all possible emission offsets. As long as the emission offsets obtained represent reasonable progress toward attainment, they will be acceptable. It is the reviewing authority's responsibility to assure that the emission offsets will be as effective as proposed by the source. An internal emission offset will be considered enforceable if it is made a SIP requirement by inclusion as a condition of the new source permit and the permit is forwarded to the appropriate EPA Regional Office.
The form of the SIP revision may be a State or local regulation, operating permit condition, consent or enforcement order, or any other mechanism available to the State that is enforceable under the Clean Air Act. If a SIP revision is required, the public hearing on the revision may be substituted for the normal public comment procedure required for all major sources under 40 CFR 51.18. The formal publication of the SIP revision approval in the
B.
In some cases, the dates for attainment of primary standards specified in the SIP under section 110 have not yet passed due to a delay in the promulgation of a plan under this section of the Act. In addition the Act provides more flexibility with respect to the dates for attainment of secondary NAAQS than for primary standards. Rather than setting specific deadlines, section 110 requires secondary NAAQS to be achieved within a “reasonable time”. Therefore, in some cases, the date for attainment of secondary standards specified in the SIP under section 110 may also not yet have passed. In such cases, a new source locating in an area designated in 40 CFR 81.3000
This appendix V sets forth the minimum criteria for determining whether a State implementation plan submitted for consideration by EPA is an official submission for purposes of review under § 51.103.
1.1 The EPA shall return to the submitting official any plan or revision thereof which fails to meet the criteria set forth in this appendix V, and request corrective action, identifying the component(s) absent or insufficient to perform a review of the submitted plan.
1.2 The EPA shall inform the submitting official whether or not a plan submission meets the requirements of this appendix V within 60 days of EPA's receipt of the submittal, but no later than 6 months after the date by which the State was required to submit the plan or revision. If a completeness determination is not made by 6 months from receipt of a submittal, the submittal shall be deemed complete by operation of law on the date 6 months from receipt. A determination of completeness under this paragraph means that the submission is an official submission for purposes of § 51.103.
The following shall be included in plan submissions for review by EPA:
2.1. Administrative Materials
(a) A formal letter of submittal from the Governor or his designee, requesting EPA approval of the plan or revision thereof (hereafter “the plan”).
(b) Evidence that the State has adopted the plan in the State code or body of regulations; or issued the permit, order, consent agreement (hereafter “document”) in final form. That evidence shall include the date of adoption or final issuance as well as the effective date of the plan, if different from the adoption/issuance date.
(c) Evidence that the State has the necessary legal authority under State law to adopt and implement the plan.
(d) A copy of the actual regulation, or document submitted for approval and incorporation by reference into the plan, including indication of the changes made to the existing approved plan, where applicable. The submittal shall be a copy of the official State regulation /document signed, stamped, dated by the appropriate State official indicating that it is fully enforceable by the State. The effective date of the regulation/document shall, whenever possible, be indicated in the document itself.
(e) Evidence that the State followed all of the procedural requirements of the State's laws and constitution in conducting and completing the adoption/issuance of the plan.
(f) Evidence that public notice was given of the proposed change consistent with procedures approved by EPA, including the date of publication of such notice.
(g) Certification that public hearings(s) were held in accordance with the information provided in the public notice and the State's laws and constitution, if applicable.
(h) Compilation of public comments and the State's response thereto.
2.2. Technical Support
(a) Identification of all regulated pollutants affected by the plan.
(b) Identification of the locations of affected sources including the EPA attainment/nonattainment designation of the locations and the status of the attainment plan for the affected areas(s).
(c) Quantification of the changes in plan allowable emissions from the affected sources; estimates of changes in current actual emissions from affected sources or, where appropriate, quantification of changes in actual emissions from affected sources through calculations of the differences between certain baseline levels and allowable emissions anticipated as a result of the revision.
(d) The State's demonstration that the national ambient air quality standards, prevention of significant deterioration increments, reasonable further progress demonstration, and visibility, as applicable, are protected if the plan is approved and implemented. For all requests to redesignate an area to attainment for a national primary ambient air quality standard, under section 107 of the Act, a revision must be submitted to provide for the maintenance of the national primary ambient air quality standards for at least 10 years as required by section 175A of the Act.
(e) Modeling information required to support the proposed revision, including input
(f) Evidence, where necessary, that emission limitations are based on continuous emission reduction technology.
(g) Evidence that the plan contains emission limitations, work practice standards and recordkeeping/reporting requirements, where necessary, to ensure emission levels.
(h) Compliance/enforcement strategies, including how compliance will be determined in practice.
(i) Special economic and technological justifications required by any applicable EPA policies, or an explanation of why such justifications are not necessary.
2.3. Exceptions
2.3.1. The EPA, for the purposes of expediting the review of the plan, has adopted a procedure referred to as “parallel processing.” Parallel processing allows a State to submit the plan prior to actual adoption by the State and provides an opportunity for the State to consider EPA comments prior to submission of a final plan for final review and action. Under these circumstances, the plan submitted will not be able to meet all of the requirements of paragraph 2.1 (all requirements of paragraph 2.2 will apply). As a result, the following exceptions apply to plans submitted explicitly for parallel processing:
(a) The letter required by paragraph 2.1(a) shall request that EPA propose approval of the proposed plan by parallel processing.
(b) In lieu of paragraph 2.1(b) the State shall submit a schedule for final adoption or issuance of the plan.
(c) In lieu of paragraph 2.1(d) the plan shall include a copy of the proposed/draft regulation or document, including indication of the proposed changes to be made to the existing approved plan, where applicable.
(d) The requirements of paragraphs 2.1(e)-2.1(h) shall not apply to plans submitted for parallel processing.
2.3.2. The exceptions granted in paragraph 2.3.1 shall apply only to EPA's determination of proposed action and all requirements of paragraph 2.1 shall be met prior to publication of EPA's final determination of plan approvability.
a. Industry and control agencies have long expressed a need for consistency in the application of air quality models for regulatory purposes. In the 1977 Clean Air Act, Congress mandated such consistency and encouraged the standardization of model applications. The Guideline on Air Quality Models (hereafter, Guideline) was first published in April 1978 to satisfy these requirements by specifying models and providing guidance for their use. The Guideline provides a common basis for estimating the air quality concentrations used in assessing control strategies and developing emission limits.
b. The continuing development of new air quality models in response to regulatory requirements and the expanded requirements for models to cover even more complex problems have emphasized the need for periodic review and update of guidance on these techniques. Four primary on-going activities provide direct input to revisions of the Guideline. The first is a series of annual EPA workshops conducted for the purpose of ensuring consistency and providing clarification in the application of models. The second activity, directed toward the improvement of modeling procedures, is the cooperative agreement that EPA has with the scientific community represented by the American Meteorological Society. This agreement provides scientific assessment of procedures and proposed techniques and sponsors workshops on key technical issues. The third activity is the solicitation and review of new models from the technical and user community. In the March 27, 1980
c. Based primarily on these four activities, this document embodies all revisions to the Guideline Although the text has been revised from the original 1978 guide, the present content and topics are similar. As necessary, new sections and topics are included. EPA does not make changes to the guidance on a predetermined schedule, but rather on an as needed basis. EPA believes that revisions of the Guideline should be timely and responsive to user needs and should involve public participation to the greatest possible extent. All future changes to the guidance will be
4.2.2 Refined Analytical Techniques
a. The Guideline recommends air quality modeling techniques that should be applied
b. Due to limitations in the spatial and temporal coverage of air quality measurements, monitoring data normally are not sufficient as the sole basis for demonstrating the adequacy of emission limits for existing sources. Also, the impacts of new sources that do not yet exist can only be determined through modeling. Thus, models, while uniquely filling one program need, have become a primary analytical tool in most air quality assessments. Air quality measurements though can be used in a complementary manner to dispersion models, with due regard for the strengths and weaknesses of both analysis techniques. Measurements are particularly useful in assessing the accuracy of model estimates. The use of air quality measurements alone however could be preferable, as detailed in a later section of this document, when models are found to be unacceptable and monitoring data with sufficient spatial and temporal coverage are available.
c. It would be advantageous to categorize the various regulatory programs and to apply a designated model to each proposed source needing analysis under a given program. However, the diversity of the nation's topography and climate, and variations in source configurations and operating characteristics dictate against a strict modeling “cookbook.” There is no one model capable of properly addressing all conceivable situations even within a broad category such as point sources. Meteorological phenomena associated with threats to air quality standards are rarely amenable to a single mathematical treatment; thus, case-by-case analysis and judgment are frequently required. As modeling efforts become more complex, it is increasingly important that they be directed by highly competent individuals with a broad range of experience and knowledge in air quality meteorology. Further, they should be coordinated closely with specialists in emissions characteristics, air monitoring and data processing. The judgment of experienced meteorologists and analysts is essential.
d. The model that most accurately estimates concentrations in the area of interest is always sought. However, it is clear from the needs expressed by the States and EPA Regional Offices, by many industries and trade associations, and also by the deliberations of Congress, that consistency in the selection and application of models and data bases should also be sought, even in case-by-case analyses. Consistency ensures that air quality control agencies and the general public have a common basis for estimating pollutant concentrations, assessing control strategies and specifying emission limits. Such consistency is not, however, promoted at the expense of model and data base accuracy. This guide provides a consistent basis for selection of the most accurate models and data bases for use in air quality assessments.
e. Recommendations are made in this guide concerning air quality models, data bases, requirements for concentration estimates, the use of measured data in lieu of model estimates, and model evaluation procedures. Models are identified for some specific applications. The guidance provided here should be followed in all air quality analyses relative to State Implementation Plans and in analyses required by EPA, State and local agency air programs. The EPA may approve the use of another technique that can be demonstrated to be more appropriate than those recommended in this guide. This is discussed at greater length in section 3.0. In all cases, the model applied to a given situation should be the one that provides the most accurate representation of atmospheric transport, dispersion, and chemical transformations in the area of interest. However, to ensure consistency, deviations from this guide should be carefully documented and fully supported.
f. From time to time situations arise requiring clarification of the intent of the guidance on a specific topic. Periodic workshops are held with the EPA Regional Meteorologists to ensure consistency in modeling guidance and to promote the use of more accurate air quality models and data bases. The workshops serve to provide further explanations of Guideline requirements to the Regional Offices and workshop reports are issued with this clarifying information. In addition, findings from on-going research programs, new model submittals, or results from model evaluations and applications are continuously evaluated. Based on this information changes in the guidance may be indicated.
g. All changes to the Guideline must follow rulemaking requirements since the Guideline is codified in this appendix W of part 51. EPA will promulgate proposed and final rules in the
h. A wide range of topics on modeling and data bases are discussed in the Guideline. Chapter 2 gives an overview of models and their appropriate use. Chapter 3 provides specific guidance on the use of “preferred” air quality models and on the selection of alternative techniques. Chapters 4 through 7 provide recommendations on modeling techniques for application to simple-terrain stationary source problems, complex terrain problems, and mobile source problems. Specific modeling requirements for selected regulatory issues are also addressed. Chapter 8 discusses issues common to many modeling analyses, including acceptable model components. Chapter 9 makes recommendations for data inputs to models including source, meteorological and background air quality data. Chapter 10 covers the uncertainty in model estimates and how that information can be useful to the regulatory decision-maker. The last chapter summarizes how estimates and measurements of air quality are used in assessing source impact and in evaluating control strategies.
i. This appendix W itself contains three appendices: A, B, and C. Thus, when reference is made to “Appendix A”, it refers to appendix A to this appendix W. Appendices B and C are referenced in the same way.
j. Appendix A contains summaries of refined air quality models that are “preferred” for specific applications; both EPA models and models developed by others are included. Appendix B contains summaries of other refined models that may be considered with a case-specific justification. Appendix C contains a checklist of requirements for an air quality analysis.
a. Before attempting to implement the guidance contained in this appendix, the reader should be aware of certain general information concerning air quality models and their use. Such information is provided in this section.
a. The extent to which a specific air quality model is suitable for the evaluation of source impact depends upon several factors. These include: (1) The meteorological and topographic complexities of the area; (2) the level of detail and accuracy needed for the analysis; (3) the technical competence of those undertaking such simulation modeling; (4) the resources available; and (5) the detail and accuracy of the data base, i.e., emissions inventory, meteorological data, and air quality data. Appropriate data should be available before any attempt is made to apply a model. A model that requires detailed, precise, input data should not be used when such data are unavailable. However, assuming the data are adequate, the greater the detail with which a model considers the spatial and temporal variations in emissions and meteorological conditions, the greater the ability to evaluate the source impact and to distinguish the effects of various control strategies.
b. Air quality models have been applied with the most accuracy or the least degree of uncertainty to simulations of long term averages in areas with relatively simple topography. Areas subject to major topographic influences experience meteorological complexities that are extremely difficult to simulate. Although models are available for such circumstances, they are frequently site specific and resource intensive. In the absence of a model capable of simulating such complexities, only a preliminary approximation may be feasible until such time as better models and data bases become available.
c. Models are highly specialized tools. Competent and experienced personnel are an essential prerequisite to the successful application of simulation models. The need for specialists is critical when the more sophisticated models are used or the area being investigated has complicated meteorological or topographic features. A model applied improperly, or with inappropriately chosen data, can lead to serious misjudgments regarding the source impact or the effectiveness of a control strategy.
d. The resource demands generated by use of air quality models vary widely depending on the specific application. The resources required depend on the nature of the model and its complexity, the detail of the data base, the difficulty of the application, and the amount and level of expertise required. The costs of manpower and computational facilities may also be important factors in the selection and use of a model for a specific analysis. However, it should be recognized that under some sets of physical circumstances and accuracy requirements, no present model may be appropriate. Thus, consideration of these factors should not lead to selection of an inappropriate model.
a. The air quality modeling procedures discussed in this guide can be categorized into four generic classes: Gaussian, numerical, statistical or empirical, and physical. Within these classes, especially Gaussian and numerical models, a large number of individual “computational algorithms” may exist, each with its own specific applications. While each of the algorithms may have the same generic basis, e.g., Gaussian, it is accepted practice to refer to them individually as models. For example, the Industrial Source Complex (ISC) model and the RAM model are
b. Gaussian models are the most widely used techniques for estimating the impact of nonreactive pollutants. Numerical models may be more appropriate than Gaussian models for area source urban applications that involve reactive pollutants, but they require much more extensive input data bases and resources and therefore are not as widely applied. Statistical or empirical techniques are frequently employed in situations where incomplete scientific understanding of the physical and chemical processes or lack of the required data bases make the use of a Gaussian or numerical model impractical. Various specific models in these three generic types are discussed in the Guideline.
c. Physical modeling, the fourth generic type, involves the use of wind tunnel or other fluid modeling facilities. This class of modeling is a complex process requiring a high level of technical expertise, as well as access to the necessary facilities. Nevertheless, physical modeling may be useful for complex flow situations, such as building, terrain or stack downwash conditions, plume impact on elevated terrain, diffusion in an urban environment, or diffusion in complex terrain. It is particularly applicable to such situations for a source or group of sources in a geographic area limited to a few square kilometers. If physical modeling is available and its applicability demonstrated, it may be the best technique. A discussion of physical modeling is beyond the scope of this guide. The EPA publication “Guideline for Fluid Modeling of Atmospheric Diffusion,”
a. In addition to the various classes of models, there are two levels of sophistication. The first level consists of general, relatively simple estimation techniques that provide conservative estimates of the air quality impact of a specific source, or source category. These are screening techniques or screening models. The purpose of such techniques is to eliminate the need of further more detailed modeling for those sources that clearly will not cause or contribute to ambient concentrations in excess of either the National Ambient Air Quality Standards (NAAQS)
b. The second level consists of those analytical techniques that provide more detailed treatment of physical and chemical atmospheric processes, require more detailed and precise input data, and provide more specialized concentration estimates. As a result they provide a more refined and, at least theoretically, a more accurate estimate of source impact and the effectiveness of control strategies. These are referred to as refined models.
c. The use of screening techniques followed by a more refined analysis is always desirable, however there are situations where the screening techniques are practically and technically the only viable option for estimating source impact. In such cases, an attempt should be made to acquire or improve the necessary data bases and to develop appropriate analytical techniques.
a. This section recommends refined modeling techniques that are preferred for use in regulatory air quality programs. The status of models developed by EPA, as well as those submitted to EPA for review and possible inclusion in this guidance, is discussed. The section also addresses the selection of models for individual cases and provides recommendations for situations where the preferred models are not applicable. Two additional sources of modeling guidance, the Model Clearinghouse
b. In all regulatory analyses, especially if other than preferred models are selected for use, early discussions among Regional Office staff, State and local control agencies, industry representatives, and where appropriate, the Federal Land Manager, are invaluable and are encouraged. Agreement on the data base to be used, modeling techniques to be applied and the overall technical approach, prior to the actual analyses, helps avoid misunderstandings concerning the final results and may reduce the later need for additional analyses. The use of an air quality checklist, such as presented in appendix C, and the preparation of a written protocol help to keep misunderstandings at a minimum.
c. It should not be construed that the preferred models identified here are to be permanently used to the exclusion of all others or that they are the only models available for relating emissions to air quality. The model that most accurately estimates concentrations in the area of interest is always sought. However, designation of specific models is needed to promote consistency in model selection and application.
d. The 1980 solicitation of new or different models from the technical community
a. EPA has developed approximately 10 models suitable for regulatory application. More than 20 additional models were submitted by private developers for possible inclusion in the Guideline. These refined models have all been organized into eight categories of use: rural, urban industrial complex, reactive pollutants, mobile sources, complex terrain, visibility, and long range transport. They are undergoing an intensive evaluation by category. The evaluation exercises
b. When a single model is found to perform better than others in a given category, it is recommended for application in that category as a preferred model and listed in appendix A. If no one model is found to clearly perform better through the evaluation exercise, then the preferred model listed in appendix A is selected on the basis of other factors such as past use, public familiarity, cost or resource requirements, and availability. No further evaluation of a preferred model is required if the source follows EPA recommendations specified for the model in the Guideline. The models not specifically recommended for use in a particular category are summarized in appendix B. These models should be compared with measured air quality data when they are used for regulatory applications consistent with recommendations in section 3.2.
c. The solicitation of new refined models which are based on sounder scientific principles and which more reliably estimate pollutant concentrations is considered by EPA to be continuous. Models that are submitted in accordance with the provisions outlined in the
i. The model must be computerized and functioning in a common Fortran language suitable for use on a variety of computer systems.
ii. The model must be documented in a user's guide which identifies the mathematics of the model, data requirements and program operating characteristics at a level of detail comparable to that available for currently recommended models, e.g., the Industrial Source Complex (ISC) model.
iii. The model must be accompanied by a complete test data set including input parameters and output results. The test data must be included in the user's guide as well as provided in computer-readable form.
iv. The model must be useful to typical users, e.g., State air pollution control agencies, for specific air quality control problems. Such users should be able to operate the computer program(s) from available documentation.
v. The model documentation must include a comparison with air quality data or with other well-established analytical techniques.
vi. The developer must be willing to make the model available to users at reasonable cost or make it available for public access through the National Technical Information Service; the model cannot be proprietary.
d. The evaluation process will include a determination of technical merit, in accordance with the above six items including the practicality of the model for use in ongoing regulatory programs. Each model will also be subjected to a performance evaluation for an appropriate data base and to a peer scientific review. Models for wide use (not just an isolated case!) found to perform better, based on an evaluation for the same data bases used to evaluate models in appendix A, will be proposed for inclusion as preferred models in future Guideline revisions.
a. Appendix A identifies refined models that are preferred for use in regulatory applications. If a model is required for a particular application, the user should select a model from appendix A. These models may be used without a formal demonstration of applicability as long as they are used as indicated in each model summary of appendix A. Further recommendations for the application of these models to specific source problems are found in subsequent sections of the Guideline.
b. If changes are made to a preferred model without affecting the concentration estimates, the preferred status of the model is unchanged. Examples of modifications that do not affect concentrations are those made to enable use of a different computer or those that affect only the format or averaging time of the model results. However, when any changes are made, the Regional Administrator should require a test case example to demonstrate that the concentration estimates are not affected.
c. A preferred model should be operated with the options listed in appendix A as “Recommendations for Regulatory Use.” If other options are exercised, the model is no
a. Selection of the best techniques for each individual air quality analysis is always encouraged, but the selection should be done in a consistent manner. A simple listing of models in this guide cannot alone achieve that consistency nor can it necessarily provide the best model for all possible situations. An EPA document, “Interim Procedures for Evaluating Air Quality Models”,
b. This section discusses the use of alternate modeling techniques and defines three situations when alternative models may be used.
a. Determination of acceptability of a model is a Regional Office responsibility. Where the Regional Administrator finds that an alternative model is more appropriate than a preferred model, that model may be used subject to the recommendations below. This finding will normally result from a determination that (1) A preferred air quality model is not appropriate for the particular application; or (2) a more appropriate model or analytical procedure is available and is applicable.
b. An alternative model should be evaluated from both a theoretical and a performance perspective before it is selected for use. There are three separate conditions under which such a model will normally be approved for use: (1) If a demonstration can be made that the model produces concentration estimates equivalent to the estimates obtained using a preferred model; (2) if a statistical performance evaluation has been conducted using measured air quality data and the results of that evaluation indicate the alternative model performs better for the application than a comparable model in appendix A; and (3) if there is no preferred model for the specific application but a refined model is needed to satisfy regulatory requirements. Any one of these three separate conditions may warrant use of an alternative model. Some known alternative models that are applicable for selected situations are contained in appendix B. However, inclusion there does not infer any unique status relative to other alternative models that are being or will be developed in the future.
c. Equivalency is established by demonstrating that the maximum or highest, second highest concentrations are within 2 percent of the estimates obtained from the preferred model. The option to show equivalency is intended as a simple demonstration of acceptability for an alternative model that is so nearly identical (or contains options that can make it identical) to a preferred model that it can be treated for practical purposes as the preferred model. Two percent was selected as the basis for equivalency since it is a rough approximation of the fraction that PSD Class I increments are of the NAAQS for SO
d. The procedures and techniques for determining the acceptability of a model for an individual case based on superior performance is contained in the document entitled “Interim Procedures for Evaluating Air Quality Models”,
e. When no appendix A model is applicable to the modeling problem, an alternative refined model may be used provided that:
i. The model can be demonstrated to be applicable to the problem on a theoretical basis; and
ii. The data bases which are necessary to perform the analysis are available and adequate; and
iii. Performance evaluations of the model in similar circumstances have shown that the model is not biased toward underestimates; or
iv. After consultation with the EPA Regional Office, a second model is selected as a baseline or reference point for performance and the interim procedures
a. The Regional Administrator has the authority to select models that are appropriate for use in a given situation. However, there is a need for assistance and guidance in the selection process so that fairness and consistency in modeling decisions is fostered among the various Regional Offices and the States. To satisfy that need, EPA established the Model Clearinghouse and also holds periodic workshops with headquarters, Regional Office and State modeling representatives.
a. The Model Clearinghouse is the single EPA focal point for review of air quality simulation models proposed for use in specific regulatory applications. Details concerning the Clearinghouse and its operation are found in the document, “Model Clearinghouse: Operational Plan.”
i. Review of decisions proposed by EPA Regional Offices on the use of modeling techniques and data bases.
ii. Periodic visits to Regional Offices to gather information pertinent to regulatory model usage.
iii. Preparation of an annual report summarizing activities of the Clearinghouse including specific determinations made during the course of the year.
a. The Regional Administrator may request assistance from the Model Clearinghouse after an initial evaluation and decision has been reached concerning the application of a model, analytical technique or data base in a particular regulatory action. The Clearinghouse may also consider and evaluate the use of modeling techniques submitted in support of any regulatory action. Additional responsibilities are: (1) Review proposed action for consistency with agency policy; (2) determine technical adequacy; and (3) make recommendations concerning the technique or data base.
a. EPA conducts an annual in-house workshop for the purpose of mutual discussion and problem resolution among Regional Office modeling specialists, EPA research modeling experts, EPA Headquarters modeling and regulatory staff and representatives from State modeling programs. A summary of the issues resolved at previous workshops was issued in 1981 as “Regional Workshops on Air Quality Modeling: A Summary Report.”
a. The Regional Office should always be consulted for information and guidance concerning modeling methods and interpretations of modeling guidance, and to ensure that the air quality model user has available the latest most up-to-date policy and procedures.
a. Simple terrain, as used in this section, is considered to be an area where terrain features are all lower in elevation than the top of the stack of the source(s) in question. The models recommended in this section are generally used in the air quality impact analysis of stationary sources for most criteria pollutants. The averaging time of the concentration estimates produced by these models ranges from 1 hour to an annual average.
b. Model evaluation exercises have been conducted to determine the “best, most appropriate point source model” for use in simple terrain.
a. Point source screening techniques are an acceptable approach to air quality analyses. One such approach is contained in the EPA document “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources”.
b. All screening procedures should be adjusted to the site and problem at hand. Close attention should be paid to whether the area
a. A brief description of preferred models for refined applications is found in appendix A. Also listed in appendix A are the model input requirements, the standard options that should be selected when running the program, and output options.
b. When modeling for compliance with short term NAAQS and PSD increments is of primary concern, a short term model may also be used to provide long term concentration estimates. However, when modeling sources for which long term standards alone are applicable (e.g., lead), then the long term models should be used. The conversion from long term to short term concentration averages by any transformation technique is not acceptable in regulatory applications.
a. For the purpose of the Guideline, complex terrain is defined as terrain exceeding the height of the stack being modeled. Complex terrain dispersion models are normally applied to stationary sources of pollutants such as SO
b. A major outcome from the EPA Complex Terrain Model Development project has been the publication of a refined dispersion model (CTDM) suitable for regulatory application to plume impaction assessments in complex terrain.
c. The methods discussed in this section should be considered in two categories: (1) Screening techniques, and (2) the refined dispersion model, CTDMPLUS, discussed below and listed in appendix A.
d. Continued improvements in ability to accurately model plume dispersion in complex terrain situations can be expected, e.g., from research on lee side effects due to terrain obstacles. New approaches to improve the ability of models to realistically simulate atmospheric physics, e.g., hybrid models which incorporate an accurate wind field analysis, will ultimately provide more appropriate tools for analyses. Such hybrid modeling techniques are also acceptable for regulatory applications after the appropriate demonstration and evaluation.
a. Recommendations in this section apply primarily to those situations where the impaction of plumes on terrain at elevations equal to or greater than the plume centerline during stable atmospheric conditions are determined to be the problem. If a violation of any NAAQS or the controlling increment is indicated by using any of the preferred screening techniques, then a refined complex terrain model may be used. Phenomena such as fumigation, wind direction shear, lee-side effects, building wake- or terrain-induced downwash, deposition, chemical transformation, variable plume trajectories, and long range transport are not addressed by the recommendations in this section.
b. Where site-specific data are used for either screening or refined complex terrain models, a data base of at least 1 full-year of meteorological data is preferred. If more data are available, they should be used. Meteorological data used in the analysis should be reviewed for both spatial and temporal representativeness.
c. Placement of receptors requires very careful attention when modeling in complex terrain. Often the highest concentrations are predicted to occur under very stable conditions, when the plume is near, or impinges on, the terrain. The plume under such conditions may be quite narrow in the vertical, so that even relatively small changes in a receptor's location may substantially affect the predicted concentration. Receptors within about a kilometer of the source may be even more sensitive to location. Thus, a dense array of receptors may be required in some cases. In order to avoid excessively large computer runs due to such a large array of receptors, it is often desirable to model the area twice. The first model run would use a moderate number of receptors carefully located over the area of interest. The second model run would use a more dense array of receptors in areas showing potential for high concentrations, as indicated by the results of the first model run.
d. When CTSCREEN or CTDMPLUS is used, digitized contour data must be first processed by the CTDM Terrain Processor
e. The user is encouraged to confer with the Regional Office if any unresolvable problems are encountered with any screening or refined analytical procedures, e.g., meteorological data, receptor siting, or terrain contour processing issues.
a. Five preferred screening techniques are currently available to aid in the evaluation of concentrations due to plume impaction during stable conditions: (1) for 24-hour impacts, the Valley Screening Technique
b. The Valley Model, COMPLEX I, SHORTZ/LONGZ, and RTDM should be used only to estimate concentrations at receptors whose elevations are greater than or equal to plume height. For receptors at or below stack height, a simple terrain model should be used (see Chapter 4). Receptors between stack height and plume height present a unique problem since none of the above models were designed to handle receptors in this narrow regime, the definition of which will vary hourly as meteorological conditions vary. CTSCREEN may be used to estimate concentrations under all stability conditions at all receptors located “on terrain” above stack top, but has limited applicability in multi-source situations. As a result, the estimation of concentrations at receptors between stack height and plume height should be considered on a case-by-case basis after consultation with the EPA Regional Office; the most appropriate technique may be a function of the actual source(s) and terrain configuration unique to that application. One technique that will generally be acceptable, but is not necessarily preferred for any specific application, involves applying both a complex terrain model (except for the Valley Model) and a simple terrain model. The Valley Model should not be used for any intermediate terrain receptor. For each receptor between stack height and plume height, an hour-by-hour comparison of the concentration estimates from both models is made. The higher of the two modeled concentrations should be chosen to represent the impact at that receptor for that hour, and then used to compute the concentration for the appropriate averaging time(s). For the simple terrain models, terrain may have to be “chopped off” at stack height, since these models are frequently limited to receptors no greater than stack height.
a. The Valley Screening Technique may be used to determine 24-hour averages. This technique uses the Valley Model with the following worst-case assumptions for rural areas: (1) P-G stability “F”; (2) wind speed of 2.5 m/s; and (3) 6 hours of occurrence. For urban areas the stability should be changed to “P-G stability E.”
b. When using the Valley Screening Technique to obtain 24-hour average concentrations the following apply: (1) multiple sources should be treated individually and the concentrations for each wind direction summed; (2) only one wind direction should be used (see User's Guide,
c. The standard polar receptor grid found in the Valley Model User's Guide may not be sufficiently dense for all analyses if only one geographical scale factor is used. The user should choose an additional set of receptors at appropriate downwind distances whose elevations are equal to plume height minus 10 meters. Alternatively, the user may exercise the “Valley equivalent” option in COMPLEX I or SCREEN and note the comments above on the placement of receptors in complex terrain models.
d. When using the “Valley equivalent” option in COMPLEX I, set the wind profile exponents (PL) to 0.0, respectively, for all six stability classes.
a. CTSCREEN may be used to obtain conservative, yet realistic, worst-case estimates for receptors located on terrain above stack height. CTSCREEN accounts for the three-dimensional nature of plume and terrain interaction and requires detailed terrain data representative of the modeling domain. The model description and user's instructions are contained in the user's guide.
a. If the area is rural, COMPLEX I may be used to estimate concentrations for all averaging times. COMPLEX I is a modification of the MPTER model that incorporates the plume impaction algorithm of the Valley Model.
b. When using the “Valley equivalent” option (only) in COMPLEX I, set the wind profile exponents (PL) to 0.0, respectively, for all six stability classes. For all other regulatory uses of COMPLEX I, set the wind profile exponents to the values used in the simple terrain models, i.e., 0.07, 0.07, 0.10, 0.15, 0.35, and 0.55, respectively, for rural modeling.
c. Gradual plume rise should be used to estimate concentrations at nearby elevated receptors, if plume impaction is likely on any elevated terrain closer to the source than the distance from the source to the final plume rise (see section 8.2.5).
a. If the source is located in an urbanized (Section 8.2.8) complex terrain valley, then the suggested screening technique is SHORTZ for short-term averages or LONGZ for long-term averages. SHORTZ and LONGZ may be used as screening techniques in these complex terrain applications without demonstration and evaluation. Application of these models in other than urbanized valley situations will require the same evaluation and demonstration procedures as are required for all appendix B models.
b. Both SHORTZ and LONGZ have a number of options. When using these models as screening techniques for urbanized valley applications, the options listed in table 5-2 should be selected.
a. RTDM with the options specified in table 5-3 may be used as a screening technique in rural complex terrain situations without demonstration and evaluation.
b. The RTDM screening technique can provide a more refined concentration estimate if on-site wind speed and direction characteristic of plume dilution and transport are used as input to the model. In complex terrain, these winds can seldom be estimated accurately from the standard surface (10m level) measurements. Therefore, in order to increase confidence in model estimates, EPA recommends that wind data input to RTDM should be based on fixed measurements at stack top height. For stacks greater than 100m, the measurement height may be limited to 100m in height relative to stack base. However, for very tall stacks, see guidance in section 9.3.3.2. This recommendation is broadened to include wind data representative of plume transport height where such data are derived from measurements taken with remote sensing devices such as SODAR. The data from both fixed and remote measurements should meet quality assurance and recovery rate requirements. The user should also be aware that RTDM in the screening mode accepts the input of measured wind speeds at only one height. The default values for the wind speed profile exponents shown in table 5-3 are used in the model to determine the wind speed at other heights. RTDM uses wind speed at stack top to calculate the plume rise and the critical dividing streamline height, and the wind speed at plume transport level to calculate dilution. RTDM treats wind direction as constant with height.
c. RTDM makes use of the “critical dividing streamline” concept and thus treats plume interactions with terrain quite differently from other models such as SHORTZ
a. For screening analyses using the Valley Screening Technique, COMPLEX I or RTDM, a sector greater than 22
a. When the results of the screening analysis demonstrate a possible violation of NAAQS or the controlling PSD increments, a more refined analysis may need to be conducted.
b. The Complex Terrain Dispersion Model Plus Algorithms for Unstable Situations (CTDMPLUS) is a refined air quality model that is preferred for use in all stability conditions for complex terrain applications. CTDMPLUS is a sequential model that requires five input files: (1) General program specifications; (2) a terrain data file; (3) a receptor file; (4) a surface meteorological data file; and (5) a user created meteorological profile data file. Two optional input files consist of hourly emissions parameters and a file containing upper air data from rawinsonde data files, e.g., a National Climatic Data Center TD-6201 file, unless there are no hours categorized as unstable in the record. The model description and user instructions are contained in Volume 1 of the User's Guide.
c. The performance of CTDMPLUS is greatly improved by the use of meteorological data from several levels up to plume height. However, due to the vast range of source-plume-hill geometries possible in complex terrain, detailed requirements for meteorological monitoring in support of refined analyses using CTDMPLUS should be determined on a case-by-case basis. The following general guidance should be considered in the development of a meteorological monitoring protocol for regulatory applications of CTDMPLUS and reviewed in detail by the Regional Office before initiating any monitoring. As appropriate, the On-Site Meteorological Program Guidance document
d. Site specific meteorological data are critical to dispersion modeling in complex terrain and, consequently, the meteorological requirements are more demanding than for simple terrain. Generally, three different meteorological files (referred to as surface, profile, and rawin files) are needed to run CTDMPLUS in a regulatory mode.
e. The surface file is created by the meteorological preprocessor (METPRO)
f. The profile data file is prepared by the user with on-site measurements (from at least three levels) of wind speed, wind direction, turbulence, and potential temperature. These measurements should be obtained up
g. Locating towers on nearby terrain to obtain stack height or plume height measurements for use in profiles by CTDMPLUS should be avoided unless it can clearly be demonstrated that such measurements would be representative of conditions affecting the plume.
h. The rawin file is created by a second meteorological preprocessor (READ62)
i. In the absence of an appropriate refined model, screening results may need to be used to determine air quality impact and/or emission limits.
a. Models discussed in this section are applicable to pollutants often associated with mobile sources, e.g., ozone (O
b. A control agency with jurisdiction over areas with significant ozone problems and which has sufficient resources and data to use a photochemical dispersion model is encouraged to do so. Experience with and evaluations of the Urban Airshed Model show it to be an acceptable, refined approach, and better data bases are becoming available that support the more sophisticated analytical procedures. However, empirical models (e.g., EKMA) fill the gap between more sophisticated photochemical dispersion models and proportional (rollback) modeling techniques and may be the only applicable procedure if the available data bases are insufficient for refined dispersion modeling.
c. Models for assessing the impact of carbon monoxide emissions are needed for a number of different purposes, e.g., to evaluate the effects of point sources, congested intersections and highways, as well as the cumulative effect on ambient CO concentrations of all sources of CO in an urban area.
d. Nitrogen oxides are reactive and also an important contribution to the photochemical ozone problem. They are usually of most concern in areas of high ozone concentrations. Unless suitable photochemical dispersion models are used, assumptions regarding the conversion of NO to NO
a. The Urban Airshed Model (UAM)
b. The empirical model, City-specific EKMA,
c. Appendix B contains some additional models that may be applied on a case-by-case basis for photochemical or reactive pollutant modeling. Other photochemical models, including multi-layered trajectory models, that are available may be used if shown to be appropriate. Most photochemical dispersion models require emission data on individual hydrocarbon species and may require three dimensional meteorological information on an hourly basis. Reasonably sophisticated computer facilities are also often required. Because the input data are not universally available and studies to collect such data are very resource intensive, there are only limited evaluations of those models.
d. For those cases which involve estimating the impact on ozone concentrations due to stationary sources of VOC and NO
e. Proportional (rollback/forward) modeling is not an acceptable procedure for evaluating ozone control strategies.
a. For analyzing CO impacts at roadway intersections, users should follow the procedures in the “Guideline for Modeling Carbon Monoxide from Roadway Intersections”.
b. For analyses of highways characterized by uninterrupted traffic flows, CALINE3 is recommended, with emissions input from the latest version of the MOBILE model.
c. The recommended model for urban areawide CO analyses is RAM or Urban Airshed Model (UAM); see appendix A. Information on SIP development and requirements for using these models can be found in references 34, 96, 97 and 98.
d. Where point sources of CO are of concern, they should be treated using the screening and refined techniques described in section 4 or 5 of the Guideline.
a. A tiered screening approach is recommended to obtain annual average estimates of NO
b. For Tier 1 (the initial screen), use an appropriate Gaussian model from appendix A to estimate the maximum annual average concentration and assume a total conversion of NO to NO
c. For Tier 2 (2nd level) screening analysis, multiply the Tier 1 estimate(s) by an empirically derived NO
d. In urban areas, a proportional model may be used as a preliminary assessment to evaluate control strategies to meet the NAAQS for multiple minor sources, i.e. minor point, area and mobile sources of NO
e. To demonstrate compliance with NO
f. More refined techniques to handle special circumstances may be considered on a case-by-case basis and agreement with the reviewing authority should be obtained. Such techniques should consider individual quantities of NO and NO
a. This section covers those cases where specific techniques have been developed for special regulatory programs. Most of the programs have, or will have when fully developed, separate guidance documents that cover the program and a discussion of the tools that are needed. The following paragraphs reference those guidance documents, when they are available. No attempt has been made to provide a comprehensive discussion of each topic since the reference documents were designed to do that. This section will undergo periodic revision as new programs are added and new techniques are developed.
b. Other Federal agencies have also developed specific modeling approaches for their own regulatory or other requirements. An example of this is the three-volume manual issued by the U. S. Department of Housing and Urban Development, “Air Quality Considerations in Residential Planning.”
c. The need to estimate impacts at distances greater than 50km (the nominal distance to which EPA considers most Gaussian models applicable) is an important one especially when considering the effects from secondary pollutants. Unfortunately, models submitted to EPA have not as yet undergone sufficient field evaluation to be recommended for general use. Existing data bases from field studies at mesoscale and long range transport distances are limited in detail. This limitation is a result of the expense to perform the field studies required to verify and improve mesoscale and long range transport models. Particularly important and sparse are meteorological data adequate for generating three dimensional wind fields. Application of models to complicated terrain compounds the difficulty. EPA has completed limited evaluation of several long range transport (LRT) models against two sets of field data. The evaluation results are discussed in the document, “Evaluation of Short-Term Long-Range Transport Models.”
d. There are several regulatory programs for which air pathway analysis procedures and modeling techniques have been developed. For continuous emission releases, ISC forms the basis of many analytical techniques. EPA is continuing to evaluate the performance of a number of proprietary and public domain models for intermittent and non-stack emission releases. Until EPA completes its evaluation, it is premature to recommend specific models for air pathway analyses of intermittent and non-stack releases in the Guideline.
e. Regional scale models are used by EPA to develop and evaluate national policy and assist State and local control agencies. Two such models are the Regional Oxidant Model (ROM)
a. Fugitive dust usually refers to the dust put into the atmosphere by the wind blowing over plowed fields, dirt roads or desert or
b. Fugitive emissions are usually defined as emissions that come from an industrial source complex. They include the emissions resulting from the industrial process that are not captured and vented through a stack but may be released from various locations within the complex. Where such fugitive emissions can be properly specified, the ISC model, with consideration of gravitational settling and dry deposition, is the recommended model. In some unique cases a model developed specifically for the situation may be needed.
c. Due to the difficult nature of characterizing and modeling fugitive dust and fugitive emissions, it is recommended that the proposed procedure be cleared by the appropriate Regional Office for each specific situation before the modeling exercise is begun.
a. The particulate matter NAAQS, promulgated on July 1, 1987 (52 FR 24634), includes only particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM-10). EPA promulgated regulations for PSD increments measured as PM-10 on June 3, 1993 (58 FR 31621), which are codified at §§ 51.166(c) and 52.21(c).
b. Screening techniques like those identified in section 4 are also applicable to PM-10 and to large particles. It is recommended that subjectively determined values for “half-life” or pollutant decay not be used as a surrogate for particle removal. Conservative assumptions which do not allow removal or transformation are suggested for screening. Proportional models (rollback/forward) may not be applied for screening analysis, unless such techniques are used in conjunction with receptor modeling.
c. Refined models such as those in section 4.0 are recommended for PM-10 and large particles. However, where possible, particle size, gas-to-particle formation, and their effect on ambient concentrations may be considered. For urban-wide refined analyses CDM 2.0 (long term) or RAM (short term) should be used. ISC is recommended for point sources of small particles and for source-specific analyses of complicated sources. No model recommended for general use at this time accounts for secondary particulate formation or other transformations in a manner suitable for SIP control strategy demonstrations. Where possible, the use of receptor models
d. Under certain conditions, recommended dispersion models are not available or applicable. In such circumstances, the modeling approach should be approved by the appropriate Regional Office on a case-by-case basis. For example, where there is no recommended air quality model and area sources are a predominant component of PM-10, an attainment demonstration may be based on rollback of the apportionment derived from two reconciled receptor models, if the strategy provides a conservative demonstration of attainment. At this time, analyses involving model calculations for distances beyond 50km and under stagnation conditions should also be justified on a case-by-case basis (see sections 7.2.6 and 8.2.10).
e. As an aid to assessing the impact on ambient air quality of particulate matter generated from prescribed burning activities, reference 110 is available.
a. The air quality analyses required for lead implementation plans are given in §§ 51.83, 51.84 and 51.85. Sections 51.83 and 51.85 require the use of a modified rollback model as a minimum to demonstrate attainment of the lead air quality standard but the use of a dispersion model is the preferred approach. Section 51.83 requires the analysis of an entire urban area if the measured lead concentration in the urbanized area exceeds a quarterly (three month) average of 4.0
b. The SIP should contain an air quality analysis to determine the maximum quarterly lead concentration resulting from major lead point sources, such as smelters, gasoline additive plants, etc. For these applications the ISC model is preferred, since the model can account for deposition of particles and the impact of fugitive emissions. If the source is located in complicated terrain or is subject to unusual climatic conditions, a case-specific review by the appropriate Regional Office may be required.
c. In modeling the effect of traditional line sources (such as a specific roadway or highway) on lead air quality, dispersion models
d. To model an entire major urban area or to model areas without significant sources of lead emissions, as a minimum a proportional (rollback) model may be used for air quality analysis. The rollback philosophy assumes that measured pollutant concentrations are proportional to emissions. However, urban or other dispersion models are encouraged in these circumstances where the use of such models is feasible.
e. For further information concerning the use of models in the development of lead implementation plans, the documents “Supplementary Guidelines for Lead Implementation Plans,”
a. The visibility regulations as promulgated in December 1980
b. Guidance and a screening model, VISCREEN, is contained in the EPA document “Workbook for Plume Visual Impact Screening and Analysis (Revised).”
c. PLUVUE II, listed in appendix B, may be applied on a case-by-case basis when refined plume visibility evaluations are needed. Plume visibility models have been evaluated against several data sets.
a. The use of stack height credit in excess of Good Engineering Practice (GEP) stack height or credit resulting from any other dispersion technique is prohibited in the development of emission limitations by §§ 51.118 and 51.164. The definitions of GEP stack height and dispersion technique are contained in § 51.100. Methods and procedures for making the appropriate stack height calculations, determining stack height credits and an example of applying those techniques are found in references 46, 47, 48, and 49.
b. If stacks for new or existing major sources are found to be less than the height defined by EPA's refined formula for determining GEP height,
a. Section 165(e) of the Clean Air Act requires that suspected significant impacts on PSD Class I areas be determined. However, 50km is the useful distance to which most Gaussian models are considered accurate for setting emission limits. Since in many cases PSD analyses may show that Class I areas may be threatened at distances greater than 50km from new sources, some procedure is needed to (1) determine if a significant impact will occur, and (2) identify the model to be used in setting an emission limit if the Class I increments are threatened (models for this purpose should be approved for use on a case-by-case basis as required in section 3.2). This procedure and the models selected for use should be determined in consultation with the EPA Regional Office and the appropriate Federal Land Manager (FLM). While the ultimate decision on whether a Class I area is adversely affected is the responsibility of the permitting authority, the FLM has an affirmative responsibility to protect air quality related values that may be affected.
b. If LRT is determined to be important, then estimates utilizing an appropriate refined model for receptors at distances greater than 50 km should be obtained. MESOPUFF II, listed in appendix B, may be applied on a case-by-case basis when LRT estimates are needed. Additional information on applying this model is contained in the EPA document “A Modeling Protocol For Applying MESOPUFF II to Long Range Transport Problems”.
a. When using the models recommended or discussed in the Guideline in support of programmatic requirements not specifically covered by EPA regulations, the model user should consult the appropriate Federal or State agency to ensure the proper application and use of that model. For modeling associated with PSD permit applications that involve a Class I area, the appropriate Federal Land Manager should be consulted on all modeling questions.
b. The Offshore and Coastal Dispersion (OCD) model
c. The Emissions and Dispersion Modeling System (EDMS)
a. Modeling is becoming an increasingly important tool for regulatory control agencies to assess the air quality impact of releases of toxics and hazardous waste materials. Appropriate screening techniques
b. Several regulatory programs within EPA have developed modeling techniques and guidance for conducting air pathway analyses as noted in references 116-129. ISC forms the basis of the modeling procedures for air pathway analyses of many of these regulatory programs and, where identified, is appropriate for obtaining refined ambient concentration estimates of neutrally buoyant continuous air toxic releases from traditional sources. Appendix A to the Guideline contains additional models appropriate for obtaining refined estimates of continuous air toxic releases from traditional sources. Appendix B contains models that may be used on a case-by-case basis for obtaining refined estimates of denser-than-air intermittent gaseous releases, e.g., DEGADIS;
c. Many air toxics models require input of chemical properties and/or chemical engineering variables in order to appropriately characterize the source emissions prior to dispersion in the atmosphere; reference 132 is one source of helpful data. In addition, EPA has numerous programs to determine emission factors and other estimates of air toxic emissions. The Regional Office should be consulted for guidance on appropriate emission estimating procedures and any uncertainties that may be associated with them.
a. This section contains recommendations concerning a number of different issues not explicitly covered in other sections of this guide. The topics covered here are not specific to any one program or modeling area but are common to nearly all modeling analyses.
a. An air quality analysis for SO
b. If the air quality analyses are conducted using the period of meteorological input data recommended in section 9.3.1.2 (e.g., 5 years of NWS data or 1 year of site-specific data), then the design concentration based on the
c. When sufficient and representative data exist for less than a 5-year period from a nearby NWS site, or when on-site data have been collected for less than a full continuous year, or when it has been determined that the on site data may not be temporally representative, then the highest concentration estimate should be considered the design value. This is because the length of the data record may be too short to assure that the conditions producing worst-case estimates have been adequately sampled. The highest value is then a surrogate for the concentration that is not to be exceeded more than once per year (the wording of the deterministic standards). Also, the highest concentration should be used whenever selected worst-case conditions are input to a screening technique. This specifically applies to the use of techniques such as outlined in “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources, Revised”.
d. If the controlling concentration is an annual average value and multiple years of data (on-site or NWS) are used, then the design value is the highest of the annual averages calculated for the individual years. If the controlling concentration is a quarterly average and multiple years are used, then the highest individual quarterly average should be considered the design value.
e. As long a period of record as possible should be used in making estimates to determine design values and PSD increments. If more than 1 year of site-specific data is available, it should be used.
a. Specific instructions for the determination of design concentrations for criteria pollutants with expected exceedance standards, ozone and PM-10, are contained in special guidance documents for the preparation of SIPs for those pollutants.
a. Receptor sites for refined modeling should be utilized in sufficient detail to estimate the highest concentrations and possible violations of a NAAQS or a PSD increment. In designing a receptor network, the emphasis should be placed on receptor resolution and location, not total number of receptors. The selection of receptor sites should be a case-by-case determination taking into consideration the topography, the climatology, monitor sites, and the results of the initialscreening procedure. For large sources (those equivalent to a 500MW power plant) and where violations of the NAAQS or PSD increment are likely, 360 receptors for a polar coordinate grid system and 400 receptors for a rectangular grid system, where the distance from the source to the farthest receptor is 10km, are usually adequate to identify areas of high concentration. Additional receptors may be needed in the high concentration location if greater resolution is indicated by terrain or source factors.
a. Gaussian models used in most applications should employ dispersion coefficients consistent with those contained in the preferred models in appendix A. Factors such as averaging time, urban/rural surroundings, and type of source (point vs. line) may dictate the selection of specific coefficients. Generally, coefficients used in appendix A models are identical to, or at least based on, Pasquill-Gifford coefficients
b. Research is continuing toward the development of methods to determine dispersion coefficients directly from measured or observed variables.
c. Buoyancy-induced dispersion (BID), as identified by Pasquill,
a. The Pasquill approach to classifying stability is generally required in all preferred models (Appendix A). The Pasquill method, as modified by Turner,
b. Procedures to determine Pasquill stability categories from other than NWS data are found in subsection 9.3. Any other method to determine Pasquill stability categories must be justified on a case-by-case basis.
c. For a given model application where stability categories are the basis for selecting
d. Sector averaging, which eliminates the
a. The plume rise methods of Briggs
b. Since there is insufficient information to identify and quantify dispersion during the transitional plume rise period, gradual plume rise is not generally recommended for use. There are two exceptions where the use of gradual plume rise is appropriate: (1) In complex terrain screening procedures to determine close-in impacts; (2) when calculating the effects of building wakes. The building wake algorithm in the ISC model incorporates and automatically (i.e., internally) exercises the gradual plume rise calculations. If the building wake is calculated to affect the plume for any hour, gradual plume rise is also used in downwind dispersion calculations to the distance of final plume rise, after which final plume rise is used.
c. Stack tip downwash generally occurs with poorly constructed stacks and when the ratio of the stack exit velocity to wind speed is small. An algorithm developed by Briggs (Hanna et al.)
d. Where aerodynamic downwash occurs due to the adverse influence of nearby structures, the algorithms included in the ISC model
a. The chemical transformation of SO
b. Complete conversion of NO to NO
c. Use of models incorporating complex chemical mechanisms should be considered only on a case-by-case basis with proper demonstration of applicability. These are generally regional models not designed for the evaluation of individual sources but used primarily for region-wide evaluations. Visibility models also incorporate chemical transformation mechanisms which are an integral part of the visibility model itself and should be used in visibility assessments.
a. An “infinite half-life” should be used for estimates of particle concentrations when Gaussian models containing only exponential decay terms for treating settling and deposition are used.
b. Gravitational settling and deposition may be directly included in a model if either is a significant factor. One preferred model (ISC) contains a settling and deposition algorithm and is recommended for use when particulate matter sources can be quantified and settling and deposition are problems.
a. The selection of either rural or urban dispersion coefficients in a specific application should follow one of the procedures suggested by Irwin
b. Land Use Procedure: (1) Classify the land use within the total area, A
c. Population Density Procedure: (1) Compute the average population density, p
d. Of the two methods, the land use procedure is considered more definitive. Population density should be used with caution and should not be applied to highly industrialized areas where the population density may be low and thus a rural classification would be indicated, but the area is sufficiently built-up so that the urban land use criteria would be satisfied. In this case, the classification should already be “urban” and urban dispersion parameters should be used.
e. Sources located in an area defined as urban should be modeled using urban dispersion parameters. Sources located in areas defined as rural should be modeled using the rural dispersion parameters. For analyses of whole urban complexes, the entire area should be modeled as an urban region if most of the sources are located in areas classified as urban.
a. Fumigation occurs when a plume (or multiple plumes) is emitted into a stable layer of air and that layer is subsequently mixed to the ground either through convective transfer of heat from the surface or because of advection to less stable surroundings. Fumigation may cause excessively high concentrations but is usually rather short-lived at a given receptor. There are no recommended refined techniques to model this phenomenon. There are, however, screening procedures (see “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources”
b. Fumigation is also an important phenomenon on and near the shoreline of bodies of water. This can affect both individual plumes and area-wide emissions. When fumigation conditions are expected to occur from a source or sources with tall stacks located on or just inland of a shoreline, this should be addressed in the air quality modeling analysis. The Shoreline Dispersion Model (SDM) listed in appendix B may be applied on a case-by-case basis when air quality estimates under shoreline fumigation conditions are needed.
a. Stagnation conditions are characterized by calm or very low wind speeds, and variable wind directions. These stagnant meteorological conditions may persist for several hours to several days. During stagnation conditions, the dispersion of air pollutants, especially those from low-level emissions sources, tends to be minimized, potentially leading to relatively high ground-level concentrations.
b. When stagnation periods such as these are found to occur, they should be addressed in the air quality modeling analysis. WYNDvalley, listed in appendix B, may be applied on a case-by-case basis for stagnation periods of 24 hours or longer in valley-type situations. Caution should be exercised when applying the model to elevated point sources. Users should consult with the appropriate Regional Office prior to regulatory application of WYNDvalley.
a. Calibration of long term multi-source models has been a widely used procedure even though the limitations imposed by statistical theory on the reliability of the calibration process for long term estimates are well known.
b. Calibration of short term models is not common practice and is subject to much greater error and misunderstanding. There have been attempts by some to compare short term estimates and measurements on an event-by-event basis and then to calibrate a model with results of that comparison. This approach is severely limited by uncertainties in both source and meteorological data and therefore it is difficult to precisely estimate the concentration at an exact location for a specific increment of time. Such uncertainties make calibration of short term models of questionable benefit. Therefore, short term model calibration is unacceptable.
a. Data bases and related procedures for estimating input parameters are an integral part of the modeling procedure. The most appropriate data available should always be selected for use in modeling analyses. Concentrations can vary widely depending on the source data or meteorological data used. Input data are a major source of inconsistencies in any modeling analysis. This section attempts to minimize the uncertainty associated with data base selection and use by identifying requirements for data used in
a. Sources of pollutants can be classified as point, line and area/volume sources. Point sources are defined in terms of size and may vary between regulatory programs. The line sources most frequently considered are roadways and streets along which there are well-defined movements of motor vehicles, but they may be lines of roof vents or stacks such as in aluminum refineries. Area and volume sources are often collections of a multitude of minor sources with individually small emissions that are impractical to consider as separate point or line sources. Large area sources are typically treated as a grid network of square areas, with pollutant emissions distributed uniformly within each grid square.
b. Emission factors are compiled in an EPA publication commonly known as AP-42
a. For point source applications the load or operating condition that causes maximum ground-level concentrations should be established. As a minimum, the source should be modeled using the design capacity (100 percent load). If a source operates at greater than design capacity for periods that could result in violations of the standards or PSD increments, this load
b. Plant layout. The connection scheme between boilers and stacks, and the distance and direction between stacks, building parameters (length, width, height, location and orientation relative to stacks) for plant structures which house boilers, control equipment, and surrounding buildings within a distance of approximately five stack heights.
c. Stack parameters. For all stacks, the stack height and inside diameter (meters), and the temperature (K) and volume flow rate (actual cubic meters per second) or exit gas velocity (meters per second) for operation at 100 percent, 75 percent and 50 percent load.
d. Boiler size. For all boilers, the associated megawatts, 10
e. Boiler parameters. For all boilers, the percent excess air used, the boiler type (e.g., wet bottom, cyclone, etc.), and the type of firing (e.g., pulverized coal, front firing, etc.).
f. Operating conditions. For all boilers, the type, amount and pollutant contents of fuel, the total hours of boiler operation and the boiler capacity factor during the year, and the percent load for peak conditions.
g. Pollution control equipment parameters. For each boiler served and each pollutant affected, the type of emission control equipment, the year of its installation, its design efficiency and mass emission rate, the data of the last test and the tested efficiency, the number of hours of operation during the latest year, and the best engineering estimate of its projected efficiency if used in conjunction with coal combustion; data for any anticipated modifications or additions.
h. Data for new boilers or stacks. For all new boilers and stacks under construction and for all planned modifications to existing boilers or stacks, the scheduled date of completion, and the data or best estimates available for paragraphs b through g of this section above following completion of construction or modification.
i. In stationary point source applications for compliance with short term ambient
j. Line source modeling of streets and highways requires data on the width of the roadway and the median strip, the types and amounts of pollutant emissions, the number of lanes, the emissions from each lane and the height of emissions. The location of the ends of the straight roadway segments should be specified by appropriate grid coordinates. Detailed information and data requirements for modeling mobile sources of pollution are provided in the user's manuals for each of the models applicable to mobile sources.
k. The impact of growth on emissions should be considered in all modeling analyses covering existing sources. Increases in emissions due to planned expansion or planned fuel switches should be identified. Increases in emissions at individual sources that may be associated with a general industrial/commercial/residential expansion in multi-source urban areas should also be treated. For new sources the impact of growth on emissions should generally be considered for the period prior to the start-up date for the source. Such changes in emissions should treat increased area source emissions, changes in existing point source emissions which were not subject to preconstruction review, and emissions due to sources with permits to construct that have not yet started operation.
a. Background concentrations are an essential part of the total air quality concentration to be considered in determining source impacts. Background air quality includes pollutant concentrations due to: (1) natural sources; (2) nearby sources other than the one(s) currently under consideration; and (3) unidentified sources.
b. Typically, air quality data should be used to establish background concentrations in the vicinity of the source(s) under consideration. The monitoring network used for background determinations should conform to the same quality assurance and other requirements as those networks established for PSD purposes.
c. If the source is not isolated, it may be necessary to use a multi-source model to establish the impact of nearby sources. Background concentrations should be determined for each critical (concentration) averaging time.
a. Two options (paragraph b or c of this section) are available to determine the background concentration near isolated sources.
b. Use air quality data collected in the vicinity of the source to determine the background concentration for the averaging times of concern.
c. If there are no monitors located in the vicinity of the source, a “regional site” may be used to determine background. A “regional site” is one that is located away from the area of interest but is impacted by similar natural and distant man-made sources.
a. In multi-source areas, two components of background should be determined.
b. Nearby Sources: All sources expected to cause a significant concentration gradient in the vicinity of the source or sources under consideration for emission limit(s) should be explicitly modeled. For evaluation for compliance with the short term and annual ambient standards, the nearby sources should be modeled using the emission input data shown in table 9-1 or 9-2. The number of such sources is expected to be small except in unusual situations. The nearby source inventory should be determined in consultation with the reviewing authority. It is envisioned that the nearby sources and the sources under consideration will be evaluated together using an appropriate appendix A model.
c. The impact of the nearby sources should be examined at locations where interactions between the plume of the point source under consideration and those of nearby sources (plus natural background) can occur. Significant locations include: (1) the area of maximum impact of the point source; (2) the area of maximum impact of nearby sources; and (3) the area where all sources combine to cause maximum impact. These locations may be identified through trial and error analyses.
d. Other Sources: That portion of the background attributable to all other sources (e.g., natural sources, minor sources and distant major sources) should be determined by the procedures found in section 9.2.2 or by application of a model using table 9-1 or 9-2.
a. The meteorological data used as input to a dispersion model should be selected on the basis of spatial and climatological (temporal) representativeness as well as the ability of the individual parameters selected to characterize the transport and dispersion conditions in the area of concern. The representativeness of the data is dependent on: (1) the proximity of the meteorological monitoring site to the area under consideration; (2) the complexity of the terrain; (3) the exposure of the meteorological monitoring site; and (4) the period of time during which data are collected. The spatial representativeness of the data can be adversely affected by large distances between the source and receptors of interest and the complex topographic characteristics of the area. Temporal representativeness is a function of the year-to-year variations in weather conditions.
b. Model input data are normally obtained either from the National Weather Service or as part of an on-site measurement program. Local universities, Federal Aviation Administration (FAA), military stations, industry and pollution control agencies may also be sources of such data. Some recommendations for the use of each type of data are included in this section 9.3.
a. The model user should acquire enough meteorological data to ensure that worst-case meteorological conditions are adequately represented in the model results. The trend toward statistically based standards suggests a need for all meteorological conditions to be adequately represented in the data set selected for model input. The number of years of record needed to obtain a stable distribution of conditions depends on the variable being measured and has been estimated by Landsberg and Jacobs
a. Five years of representative meteorological data should be used when estimating concentrations with an air quality model. Consecutive years from the most recent, readily available 5-year period are preferred. The meteorological data may be data collected either onsite or at the nearest National Weather Service (NWS) station. If the source is large, e.g., a 500MW power plant, the use of 5 years of NWS meteorological data or at least 1 year of site-specific data is required.
b. If one year or more, up to five years, of site-specific data is available, these data are preferred for use in air quality analyses. Such data should have been subjected to quality assurance procedures as described in section 9.3.3.2.
c. For permitted sources whose emission limitations are based on a specific year of meteorological data that year should be added to any longer period being used (e.g., 5 years of NWS data) when modeling the facility at a later time.
a. The National Weather Service (NWS) meteorological data are routinely available and familiar to most model users. Although the NWS does not provide direct measurements of all the needed dispersion model input variables, methods have been developed and successfully used to translate the basic NWS data to the needed model input. Direct measurements of model input parameters have been made for limited model studies and those methods and techniques are becoming more widely applied; however, most model applications still rely heavily on the NWS data.
b. There are two standard formats of the NWS data for use in air quality models. The short term models use the standard hourly weather observations available from the National Climatic Data Center (NCDC). These observations are then “preprocessed” before they can be used in the models. “STAR” summaries are available from NCDC for long term model use. These are joint frequency distributions of wind speed, direction and P-G stability category. They are used as direct input to models such as the long term version of ISC.
a. The preferred short term models listed in appendix A all accept as input the NWS meteorological data preprocessed into model compatible form. Long-term (monthly seasonal or annual) preferred models use NWS “STAR” summaries. Summarized concentration estimates from the short term models may also be used to develop long-term averages; however, concentration estimates based on the two separate input data sets may not necessarily agree.
b. Although most NWS measurements are made at a standard height of 10 meters, the actual anemometer height should be used as input to the preferred model.
c. National Weather Service wind directions are reported to the nearest 10 degrees. A specific set of randomly generated numbers has been developed for use with the preferred EPA models and should be used to ensure a lack of bias in wind direction assignments within the models.
d. Data from universities, FAA, military stations, industry and pollution control agencies may be used if such data are equivalent in accuracy and detail to the NWS data.
a. Spatial or geographical representativeness is best achieved by collection of all of the needed model input data at the actual site of the source(s). Site-specific measured data are therefore preferred as model input, provided appropriate instrumentation and quality assurance procedures are followed and that the data collected are representative (free from undue local or “micro” influences) and compatible with the input requirements of the model to be used. However, direct measurements of all the needed model input parameters may not be possible. This section discusses suggestions for the collection and use of on-site data. Since the methods outlined in this section are still being tested, comparison of the model parameters derived using these site-specific data should be compared at least on a spot-check basis, with parameters derived from more conventional observations.
a. The document “On-Site Meteorological Program Guidance for Regulatory Modeling Applications”
b. All site-specific data should be reduced to hourly averages. Table 9-3 lists the wind related parameters and the averaging time requirements.
c. Solar Radiation Measurements. Total solar radiation should be measured with a reliable pyranometer, sited and operated in accordance with established on-site meteorological guidance.
d. Temperature Measurements. Temperature measurements should be made at standard shelter height (2m) in accordance with established on-site meteorological guidance.
e. Temperature Difference Measurements. Temperature difference (
f. Siting, probe placement, and operation of
g. Wind Measurements. For refined modeling applications in simple terrain situations, if a source has a stack below 100m, select the stack top height as the wind measurement height for characterization of plume dilution and transport. For sources with stacks extending above 100m, a 100m tower is suggested unless the stack top is significantly above 100m (i.e., ≥200m). In cases with stack tops ≥200m, remote sensing may be a feasible alternative. In some cases, collection of stack top wind speed may be impractical or incompatible with the input requirements of the model to be used. In such cases, the Regional Office should be consulted to determine the appropriate measurement height.
h. For refined modeling applications in complex terrain, multiple level (typically three or more) measurements of wind speed and direction, temperature and turbulence (wind fluctuation statistics) are required. Such measurements should be obtained up to the representative plume height(s) of interest (i.e., the plume height(s) under those conditions important to the determination of the design concentration). The representative plume height(s) of interest should be determined using an appropriate complex terrain screening procedure (e.g., CTSCREEN) and should be documented in the monitoring/modeling protocol. The necessary meteorological measurements should be obtained from an appropriately sited meteorological tower augmented by SODAR if the representative plume height(s) of interest exceed 100m. The meteorological tower need not exceed the lesser of the representative plume height of interest (the highest plume height if there is more than one plume height of interest) or 100m.
i. In general, the wind speed used in determining plume rise is defined as the wind speed at stack top.
j. Specifications for wind measuring instruments and systems are contained in the “On-Site Meteorological Program Guidance for Regulatory Modeling Applications”.
k. Stability Categories. The P-G stability categories, as originally defined, couple near-surface measurements of wind speed with subjectively determined insolation assessments based on hourly cloud cover and ceiling height observations. The wind speed measurements are made at or near 10m. The insolation rate is typically assessed using observations of cloud cover and ceiling height based on criteria outlined by Turner.
l. The SRDT method, described in section 6.4.4.2 of reference 66, is modified slightly from that published by Bowen et al. (1983)
m. Hours in the record having missing data should be treated according to an established data substitution protocol and after valid data retrieval requirements have been met. Such protocols are usually part of the approved monitoring program plan. Data substitution guidance is provided in section 5.3 of reference 66.
n. Meteorological Data Processors. The following meteorological preprocessors are recommended by EPA: RAMMET, PCRAMMET, STAR, PCSTAR, MPRM,
a. Treatment of calm or light and variable wind poses a special problem in model applications since Gaussian models assume that concentration is inversely proportional to wind speed. Furthermore, concentrations become unrealistically large when wind speeds less than 1 m/s are input to the model. A procedure has been developed for use with NWS data to prevent the occurrence of overly conservative concentration estimates during periods of calms. This procedure acknowledges that a Gaussian plume model does not apply during calm conditions and that our knowledge of plume behavior and wind patterns during these conditions does not, at present, permit the development of a better technique. Therefore, the procedure disregards hours which are identified as calm. The hour is treated as missing and a convention for handling missing hours is recommended.
b. Preprocessed meteorological data input to most appendix A EPA models substitute a 1.00 m/s wind speed and the previous direction for the calm hour. The new treatment of calms in those models attempts to identify the original calm cases by checking for a 1.00 m/s wind speed coincident with a wind direction equal to the previous hour's wind direction. Such cases are then treated in a prescribed manner when estimating short term concentrations.
a. Hourly concentrations calculated with Gaussian models using calms should not be considered valid; the wind and concentration estimates for these hours should be disregarded and considered to be missing. Critical concentrations for 3-, 8-, and 24-hour averages should be calculated by dividing the sum of the hourly concentration for the period by the number of valid or non-missing hours. If the total number of valid hours is less than 18 for 24-hour averages, less than 6 for 8-hour averages or less than 3 for 3-hour averages, the total concentration should be divided by 18 for the 24-hour average, 6 for the 8-hour average and 3 for the 3-hour average. For annual averages, the sum of all valid hourly concentrations is divided by the number of non-calm hours during the year. A post-processor computer program, CALMPRO
b. The recommendations in paragraph a of this section apply to the use of calms for short term averages and do not apply to the determination of long term averages using “STAR” data summaries. Calms should continue to be included in the preparation of “STAR” summaries. A treatment for calms
c. Stagnant conditions, including extended periods of calms, often produce high concentrations over wide areas for relatively long averaging periods. The standard short term Gaussian models are often not applicable to such situations. When stagnation conditions are of concern, other modeling techniques should be considered on a case-by-case basis (see also section 8.2.10).
d. When used in Gaussian models, measured on-site wind speeds of less than 1 m/s but higher than the response threshold of the instrument should be input as 1 m/s; the corresponding wind direction should also be input. Observations below the response threshold of the instrument are also set to 1 m/s but the wind direction from the previous hour is used. If the wind speed or direction can not be determined, that hour should be treated as missing and short term averages should then be calculated as described in paragraph a of this section.
a. Increasing reliance has been placed on concentration estimates from models as the primary basis for regulatory decisions concerning source permits and emission control requirements. In many situations, such as review of a proposed source, no practical alternative exists. Therefore, there is an obvious need to know how accurate models really are and how any uncertainty in the estimates affects regulatory decisions. EPA recognizes the need for incorporating such information and has sponsored workshops
a. Dispersion models generally attempt to estimate concentrations at specific sites that really represent an ensemble average of numerous repetitions of the same event. The event is characterized by measured or “known” conditions that are input to the models, e.g., wind speed, mixed layer height, surface heat flux, emission characteristics, etc. However, in addition to the known conditions, there are unmeasured or unknown variations in the conditions of this event, e.g., unresolved details of the atmospheric flow such as the turbulent velocity field. These unknown conditions may vary among repetitions of the event. As a result, deviations in observed concentrations from their ensemble average, and from the concentrations estimated by the model, are likely to occur even though the known conditions are fixed. Even with a perfect model that predicts the correct ensemble average, there are likely to be deviations from the observed concentrations in individual repetitions of the event, due to variations in the unknown conditions. The statistics of these concentration residuals are termed “inherent” uncertainty. Available evidence suggests that this source of uncertainty alone may be responsible for a typical range of variation in concentrations of as much as
b. Moreover, there is “reducible” uncertainty
c. To use the terminology correctly, reference to model accuracy should be limited to that portion of reducible uncertainty which deals with the physics and the formulation of the model. The accuracy of the model is normally determined by an evaluation procedure which involves the comparison of model concentration estimates with measured air quality data.
a. A number of studies
b. As noted in paragraph a of this section, poor correlations between paired concentrations at fixed stations may be due to “reducible” uncertainties in knowledge of the precise plume location and to unquantified inherent uncertainties. For example, Pasquill
a. The accuracy of model estimates varies with the model used, the type of application, and site-specific characteristics. Thus, it is desirable to quantify the accuracy or uncertainty associated with concentration estimates used in decision-making. Communications between modelers and decision-makers must be fostered and further developed. Communications concerning concentration estimates currently exist in most cases, but the communications dealing with the accuracy of models and its meaning to the decision-maker are limited by the lack of a technical basis for quantifying and directly including uncertainty in decisions. Procedures for quantifying and interpreting uncertainty in the practical application of such concepts are only beginning to evolve; much study is still required.
b. In all applications of models an effort is encouraged to identify the reliability of the model estimates for that particular area and to determine the magnitude and sources of error associated with the use of the model. The analyst is responsible for recognizing and quantifying limitations in the accuracy, precision and sensitivity of the procedure. Information that might be useful to the decision-maker in recognizing the seriousness of potential air quality violations includes such model accuracy estimates as accuracy of peak predictions, bias, noise, correlation, frequency distribution, spatial extent of high concentration, etc. Both space/time pairing of estimates and measurements and unpaired comparisons are recommended. Emphasis should be on the highest concentrations and the averaging times of the standards or increments of concern. Where possible, confidence intervals about the statistical values should be provided. However, while such information can be provided by the modeler to the decision-maker, it is unclear how this information should be used to make an air pollution control decision. Given a range of possible outcomes, it is easiest and tends to ensure consistency if the decision-maker confines his judgment to use of the “best estimate” provided by the modeler (i.e., the design concentration estimated by a model recommended in the Guideline or an alternate model of known accuracy). This is an indication of the practical limitations imposed by current abilities of the technical community.
c. To improve the basis for decision-making, EPA has developed and is continuing to study procedures for determining the accuracy of models, quantifying the uncertainty, and expressing confidence levels in decisions that are made concerning emissions controls.
a. A number of actions are being taken to ensure that the best model is used correctly for each regulatory application and that a model is not arbitrarily imposed. First, the Guideline clearly recommends the most appropriate model be used in each case. Preferred models, based on a number of factors, are identified for many uses. General guidance on using alternatives to the preferred models is also provided. Second, all the models in eight categories (i.e., rural, urban, industrial complex, reactive pollutants, mobile source, complex terrain, visibility and long range transport) that are candidates for inclusion in the Guideline are being subjected to a systematic performance evaluation and a peer scientific review.
b. In addition to performance evaluation of models, sensitivity analyses are encouraged since they can provide additional information on the effect of inaccuracies in the data bases and on the uncertainty in model estimates. Sensitivity analyses can aid in determining the effect of inaccuracies of variations or uncertainties in the data bases on the range of likely concentrations. Such information may be used to determine source impact and to evaluate control strategies. Where possible, information from such sensitivity analyses should be made available to the decision-maker with an appropriate interpretation of the effect on the critical concentrations.
a. No specific guidance on the consideration of model uncertainty in decision-making is being given at this time. There is incomplete technical information on measures of model uncertainty that are most relevant to the decision-maker. It is not clear how a decisionmaker could use such information, particularly given limitations of the Clean Air Act. As procedures for considering uncertainty develop and become implementable, this guidance will be changed and expanded. For the present, continued use of the “best estimate” is acceptable and is consistent with Clean Air Act requirements.
a. Procedures with respect to the review and analysis of air quality modeling and data analyses in support of SIP revisions, PSD permitting or other regulatory requirements need a certain amount of standardization to ensure consistency in the depth and comprehensiveness of both the review and the analysis itself. This section recommends procedures that permit some degree of standardization while at the same time allowing the flexibility needed to assure the technically best analysis for each regulatory application.
b. Dispersion model estimates, especially with the support of measured air quality data, are the preferred basis for air quality demonstrations. Nevertheless, there are instances where the performance of recommended dispersion modeling techniques, by comparison with observed air quality data, may be shown to be less than acceptable. Also, there may be no recommended modeling procedure suitable for the situation. In these instances, emission limitations may be established solely on the basis of observed air quality data as would be applied to a modeling analysis. The same care should be given to the analyses of the air quality data as would be applied to a modeling analysis.
c. The current NAAQS for SO
d. This section discusses general requirements for concentration estimates and identifies the relationship to emission limits. The recommendations in section 11.2 apply to: (1) revisions of State Implementation Plans; (2) the review of new sources and the prevention of significant deterioration (PSD); and (3) analyses of the emissions trades (“bubbles”).
a. Every effort should be made by the Regional Office to meet with all parties involved in either a SIP revision or a PSD permit application prior to the start of any work on such a project. During this meeting, a protocol should be established between the preparing and reviewing parties to define the procedures to be followed, the data to be collected, the model to be used, and the analysis of the source and concentration data. An example of requirements for such an effort is contained in the Air Quality Analysis Checklist included here as appendix C. This checklist suggests the level of detail required to assess the air quality resulting from the proposed action. Special cases may require additional data collection or analysis and this should be determined and agreed upon at this preapplication meeting. The protocol should be written and agreed upon by the parties concerned, although a formal legal document is not intended. Changes in such a protocol are often required as the data collection and analysis progresses. However, the protocol establishes a common understanding of the requirements.
b. An air quality analysis should begin with a screening model to determine the potential of the proposed source or control strategy to violate the PSD increment or NAAQS. It is recommended that the screening techniques found in “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources”
c. If the concentration estimates from screening techniques indicate that the PSD increment or NAAQS may be approached or exceeded, then a more refined modeling analysis is appropriate and the model user should select a model according to recommendations in sections 4.0-8.0. In some instances, no refined technique may be specified in this guide for the situation. The model user is then encouraged to submit a model developed specifically for the case at hand. If that is not possible, a screening technique may supply the needed results.
d. Regional Offices should require permit applicants to incorporate the pollutant contributions of all sources into their analysis. Where necessary this may include emissions associated with growth in the area of impact of the new or modified source's impact. PSD air quality assessments should consider the amount of the allowable air quality increment that has already been granted to any other sources. Therefore, the most recent source applicant should model the existing or permitted sources in addition to the one currently under consideration. This would permit the use of newly acquired data or improved modeling techniques if such have become available since the last source was permitted. When remodeling, the worst case used in the previous modeling analysis should be one set of conditions modeled in the new analysis. All sources should be modeled for each set of meteorological conditions selected and for all receptor sites used in the previous applications as well as new sites specific to the new source.
a. Modeling is the preferred method for determining emission limitations for both new and existing sources. When a preferred model is available, model results alone (including background) are sufficient. Monitoring will normally not be accepted as the sole basis for emission limitation determination in flat terrain areas. In some instances when the modeling technique available is only a screening technique, the addition of air quality data to the analysis may lend credence to model results.
b. There are circumstances where there is no applicable model, and measured data may need to be used. Examples of such situations are: (1) complex terrain locations; (2) land/water interface areas; and (3) urban locations with a large fraction of particulate emissions from nontraditional sources. However, only in the case of an existing source should monitoring data alone be a basis for emission limits. In addition, the following items should be considered prior to the acceptance of the measured data:
i. Does a monitoring network exist for the pollutants and averaging times of concern?
ii. Has the monitoring network been designed to locate points of maximum concentration?
iii. Do the monitoring network and the data reduction and storage procedures meet EPA monitoring and quality assurance requirements?
iv. Do the data set and the analysis allow impact of the most important individual sources to be identified if more than one source or emission point is involved?
v. Is at least one full year of valid ambient data available?
vi. Can it be demonstrated through the comparison of monitored data with model results that available models are not applicable?
c. The number of monitors required is a function of the problem being considered. The source configuration, terrain configuration, and meteorological variations all have an impact on number and placement of monitors. Decisions can only be made on a case-by-case basis. The Interim Procedures for Evaluating Air Quality Models
d. Sources should obtain approval from the Regional Office or reviewing authority for the monitoring network prior to the start of monitoring. A monitoring protocol agreed to by all concerned parties is highly desirable. The design of the network, the number, type and location of the monitors, the sampling period, averaging time as well as the need for meteorological monitoring or the use of mobile sampling or plume tracking techniques, should all be specified in the protocol and agreed upon prior to start-up of the network.
a. Emission limits should be based on concentration estimates for the averaging time that results in the most stringent control requirements. The concentration used in specifying emission limits is called the design value or design concentration and is a sum of the concentration contributed by the source and the background concentration.
b. To determine the averaging time for the design value, the most restrictive National Ambient Air Quality Standard (NAAQS) should be identified by calculating, for each averaging time, the ratio of the applicable NAAQS (S)− background (B) to the predicted concentration (P) (i.e., (S−B)/P). The averaging time with the lowest ratio identifies the most restrictive standard. If the annual average is the most restrictive, the highest estimated annual average concentration from one or a number of years of data is the design value. When short term standards are most restrictive, it may be necessary to consider a broader range of concentrations than the highest value. For example, for pollutants such as SO
c. When the highest, second-highest concentration is used in assessing potential violations of a short term NAAQS, criteria that are identified in “Guideline for Interpretation of Air Quality Standards”
a. For new or modified sources predicted to have a significant ambient impact
a. The allowable PSD increments for criteria pollutants are established by regulation and cited in § 51.166. These maximum allowable increases in pollutant concentrations may be exceeded once per year at each site, except for the annual increment that may not be exceeded. The highest, second-highest increase in estimated concentrations for the short term averages as determined by a model should be less than or equal to the permitted increment. The modeled annual averages should not exceed the increment.
b. Screening techniques defined in sections 4.0 and 5.0 can sometimes be used to estimate short term incremental concentrations for the first new source that triggers the baseline in a given area. However, when multiple increment-consuming sources are involved in the calculation, the use of a refined model with at least 1 year of on-site or 5 years of off-site NWS data is normally required. In such cases, sequential modeling must demonstrate that the allowable increments are not exceeded temporally and spatially, i.e., for all receptors for each time period throughout the year(s) (time period means the appropriate PSD averaging time, e.g., 3-hour, 24-hour, etc.).
c. The PSD regulations require an estimation of the SO
a. EPA's final Emissions Trading Policy, commonly referred to as the “bubble policy,” was published in the
b. Emission increases and decreases within the bubble should result in ambient air quality equivalence. Two levels of analysis are defined for establishing this equivalence. In a Level I analysis the source configuration and setting must meet certain limitations (defined in the policy) that ensure ambient equivalence; no modeling is required. In a Level II analysis a modeling demonstration of ambient equivalence is required but only the sources involved in the emissions trade are modeled. The resulting ambient estimates of net increases/decreases are compared to a set of significance levels to determine if the bubble can be approved. A Level II analysis requires the use of a refined model and the most recent readily available full year of representative meteorological data. Sequential modeling must demonstrate that the significance levels are met temporally and spatially, i.e., for all receptors for each time period throughout the year (time period means the appropriate NAAQS averaging time, e.g., 3-hour, 24-hour, etc.).
c. For those bubbles that cannot meet the Level I or Level II requirements, the Emissions Trading Policy allows for a Level III analysis. A Level III analysis, from a modeling standpoint, is generally equivalent to the requirements for a standard SIP revision where all sources (and background) are considered and the estimates are compared to the NAAQS as in section 11.2.3.2.
d. The Emissions Trading Policy allows States to adopt generic regulations for processing bubbles. The modeling procedures recommended in the Guideline apply to such generic regulations. However, an added requirement is that the modeling procedures contained in any generic regulation must be replicable such that there is no doubt as to how each individual bubble will be modeled. In general this means that the models, the data bases and the procedures for applying the model must be defined in the regulation. The consequences of the replicability requirement are that bubbles for sources located in complex terrain and certain industrial sources where judgments must be made on source characterization cannot be handled generically.
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112. DiCristofaro, D.C. and S.R. Hanna, 1989. The Offshore and Coastal Dispersion (OCD) Model, Volume I: User's Guide, Volume II: Appendices. Version 4 Prepared for Minerals Management Services by Sigma Research Corporation, Westford, MA. (Docket No. A-88-04, II-D-A-06)
113. Federal Aviation Administration, 1988. A Microcomputer Pollution Model for Civilian Airports and Air Force Bases, Model Description, Model Application and Background, and EDMS User's Guide (June 1991). Federal Aviation Administration Publication Nos. FAA-EE-88-4 and 5; FAA-EE-91-3, respectively. United States Air Force Publication Nos. ESL-TR-88-53 and 55; ESL-TR-
114. Environmental Protection Agency, 1992. Workbook of Screening Techniques for Assessing Impacts of Toxic Air Pollutants (Revised). EPA Publication No. EPA-454/R-92-024. U.S. Environmental Protection Agency, Research Triangle Park, NC.
115. Environmental Protection Agency, 1990. User's Guide to TSCREEN: A Model for Screening Toxic Air Pollutant Concentrations. EPA Publication No. EPA-450/4-90-013. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 91-141820)
116. Environmental Protection Agency, 1989. Hazardous Waste TSDF Fugitive Particulate Matter Air Emissions Guidance Document. EPA Publication No. EPA-450/3-89-019. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 90-103250)
117. Environmental Protection Agency, 1989. Procedures for Conducting Air Pathway Analyses for Superfund Applications, Volume I Applications of Air Pathway Analyses for Superfund Activities and Volume IV Procedures for Dispersion Modeling and Air Monitoring for Superfund Air Pathway Analysis, EPA-450/1-89-001 and 004. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS Nos. PB 89-113374 and PB 89-113382)
118. Environmental Protection Agency, 1988. Air Dispersion Modeling as Applied to Hazardous Waste Incinerator Evaluations, An Introduction For the Permit Writer. U.S. Environmental Protection Agency, Research Triangle Park, NC. (Docket No. A-88-04, II-J-10)
119. Environmental Protection Agency, 1989. U.S. EPA Office of Toxic Substances Graphical Exposure Modeling System (GEMS) User's Guide and GAMS Version 3.0 User's Guide (DRAFT). Prepared under Contract No. 68-02-0481 for the U.S. Environmental Protection Agency, Washington, D.C. (Docket No. A-88-04, II-J-5a and II-J-13)
120. Federal Emergency Management Agency, 1989. Handbook of Chemical Hazard Analysis Procedures. Available on request by writing to: Federal Emergency Management Agency, Publications Office, 500 C Street, S.W., Washington, D.C. 20472.
121. Environmental Protection Agency, 1987. Technical Guidance for Hazards Analysis: Emergency Planning for Extremely Hazardous Substances. Available on request by telephone: 1-800-535-0202.
122. Environmental Protection Agency, 1988. Superfund Exposure Assessment Manual. EPA-540/1-88-001, OSWER Directive 9285.5-1. Office of Remedial Response, Washington, D.C. 20460. (NTIS No. PB 89-135859)
123. Environmental Protection Agency, 1989. Incineration of Sewage Sludge; Technical Support Document. Office of Water Regulations and Standards, Washington, D.C. 20460. (NTIS No. PB 89-136592)
124. Environmental Protection Agency, 1989. Sludge Incineration Modeling (SIM) System User's Guide (Draft). Office of Pesticides and Toxic Substances, Exposure Evaluation Division, Washington, D.C. 20460. (NTIS No. PB 89-138762)
125. Environmental Protection Agency, 1989. Risk Assessment Guidance for Superfund. Volume I: Human Health Evaluation Manual Part A. (Interim Final). OSWER Directive 9285.7-01a. Office of Solid Waste and Emergency Response, Washington, D.C. 20460.
126. Environmental Protection Agency, 1986. User's Manual for the Human Exposure Model (HEM). EPA Publication No. EPA-450/5-86-001. Office of Air Quality Planning and Standards, Research Triangle Park, NC. 27711.
127. Environmental Protection Agency, 1992. A Tiered Modeling Approach for Assessing the Risks Due to Sources of Hazardous Air Pollutants. EPA Publication No. EPA-450/4-92-001. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 92-164748)
128. Environmental Protection Agency, 1992. Toxic Modeling System Short-term (TOXST) User's Guide. EPA Publication No. EPA-450/4-92-002. Environmental Protection Agency, Research Triangle Park, NC.
129. Environmental Protection Agency, 1992. Toxic Modeling System Long-term (TOXLT) User's Guide. EPA Publication No. EPA-450/4-92-003. Environmental Protection Agency, Research Triangle Park, NC.
130. Environmental Protection Agency, 1989. User's Guide for the DEGADIS 2.1 Dense Gas Dispersion Model. EPA Publication No. EPA-450/4-89-019. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 90-213893)
131. Environmental Protection Agency, 1993. Guidance on the Application of Refined Models for Air Toxics Releases. EPA Publication No. EPA-450/4-91-007. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 91-190983)
132. Perry, R.H. and Chilton, C.H., 1973.
133. Environmental Protection Agency, 1988. User's Guide to SDM—A Shoreline Dispersion Model. EPA Publication No. EPA-450/4-88-017. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 89-164305)
134. Environmental Protection Agency, 1987. Analysis and Evaluation of Statistical
135. Environmental Protection Agency, 1996. Meteorological Processor for Regulatory Models (MPRM) User's Guide. EPA Publication No. EPA-454/B-96-002. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 96-180518)
136. Bowen, B.M., J.M. Dewart and A.I. Chen, 1983. Stability Class Determination: A Comparison for One Site. Proceedings, Sixth Symposium on Turbulence and Diffusion. American Meteorological Society, Boston, MA; pp. 211-214. (Docket No. A-92-65, II-A-7)
137. Environmental Protection Agency, 1993. An Evaluation of a Solar Radiation/Delta-T (SRDT) Method for Estimating Pasquill-Gifford (P-G) Stability Categories. EPA Publication No. EPA-454/R-93-055. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 94-113958)
138. Environmental Protection Agency, 1993. PCRAMMET User's Guide. EPA Publication No. EPA-454/B-93-009. U.S. Environmental Protection Agency, Research Triangle Park, NC.
139. American Society of Mechanical Engineers, 1979. Recommended Guide for the Prediction of Airborne Effluents, Third Edition. American Society of Mechanical Engineers, New York, NY.
American Meteorological Society, 1971-1985. Symposia on Turbulence, Diffusion, and Air Pollution (1st-7th), Boston, MA.
American Meteorological Society, 1977-1984. Joint Conferences on Applications of Air Pollution Meteorology (1st-4th). Sponsored by the American Meteorological Society and the Air Pollution Control Association, Boston, MA.
American Meteorological Society, 1978. Accuracy of Dispersion Models. Bulletin of the American Meteorological Society, 59(8): 1025-1026.
American Meteorological Society, 1981. Air Quality Modeling and the Clean Air Act: Recommendations to EPA on Dispersion Modeling for Regulatory Applications, Boston, MA.
Briggs, G.A., 1969. Plume Rise. U.S. Atomic Energy Commission Critical Review Series, Oak Ridge National Laboratory, Oak Ridge, TN.
Dickerson, W.H. and P.H. Gudiksen, 1980. ASCOT FY 79 Program Report. Report UCRL—52899, ASCOT 80-1. Lawrence Livermore National Laboratory, Livermore, CA.
Drake, R.L. and S.M. Barrager, 1979. Mathematical Models for Atmospheric Pollutants. EPRI EA-1131. Electric Power Research Institute, Palo Alto, CA.
Environmental Protection Agency, 1978. Workbook for Comparison of Air Quality Models. EPA Publication No. EPA-450/2-78-028a and b. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Fox, D.G., and J.E. Fairobent, 1981. NCAQ Panel Examines Uses and Limitations of Air Quality Models. Bulletin of the American Meteorological Society, 62(2): 218-221.
Gifford, F.A., 1976. Turbulent Diffusion Typing Schemes: A Review. Nuclear Safety, 17(1): 68-86.
Gudiksen, P.H., and M.H. Dickerson, Eds., Executive Summary: Atmospheric Studies in Complex Terrain Technical Progress Report FY-1979 Through FY-1983. Lawrence Livermore National Laboratory, Livermore, CA. (Docket Reference No. II-I-103).
Hales, J.M., 1976. Tall Stacks and the Atmospheric Environment. EPA Publication No. EPA-450/3-76-007. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Hanna, S.R., G.A. Briggs, J. Deardorff, B.A. Egan, G.A. Gifford and F. Pasquill, 1977. AMS Workshop on Stability Classification Schemes And Sigma Curves—Summary of Recommendations. Bulletin of the American Meteorological Society, 58(12): 1305-1309.
Hanna, S.R., G.A. Briggs and R.P. Hosker, Jr., 1982. Handbook on Atmospheric Diffusion. Technical Information Center, U.S. Department of Energy, Washington, D.C.
Haugen, D.A., Workshop Coordinator, 1975. Lectures on Air Pollution and Environmental Impact Analyses. Sponsored by the American Meteorological Society, Boston, MA.
Hoffnagle, G.F., M.E. Smith, T.V. Crawford and T.J. Lockhart, 1981. On-site Meteorological Instrumentation Requirements to Characterize Diffusion from Point Sources—A Workshop, 15-17 January 1980, Raleigh, NC. Bulletin of the American Meteorological Society, 62(2): 255-261.
McMahon, R.A. and P.J. Denison, 1979. Empirical Atmospheric Deposition Parameters—A Survey. Atmospheric Environment, 13: 571-585.
McRae, G.J., J.A. Leone and J.H. Seinfeld, 1983. Evaluation of Chemical Reaction Mechanisms for Photochemical Smog. Part I: Mechanism Descriptions and Documentation. EPA Publication No. EPA-600/3/83-086. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Pasquill, F. and F.B. Smith, 1983. Atmospheric Diffusion, 3rd Edition. Ellis Horwood Limited, Chichester, West Sussex, England, 438 pp.
Randerson, D., Ed., 1984. Atmospheric Science and Power Production. DOE/TIC
Roberts, J.J., Ed., 1977. Report to U.S. EPA of the Specialists' Conference on the EPA Modeling Guideline. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Smith, M.E., Ed., 1973. Recommended Guide for the Prediction of the Dispersion of Airborne Effluents. The American Society of Mechanical Engineers, New York, NY.
Stern, A.C., Ed., 1976. Air Pollution, Third Edition, Volume I: Air Pollutants, Their Transformation and Transport. Academic Press, New York, NY.
Turner, D.B., 1979. Atmospheric Dispersion Modeling: A Critical Review. Journal of the Air Pollution Control Association, 29(5): 502-519.
Whiteman, C.D. and K.J. Allwine, 1982. Green River Ambient Model Assessment Program FY-1982 Progress Report. PNL-4520. Pacific Northwest Laboratory, Richland, WA.
(1) Natural sources;
(2) Nearby sources other than the one(s) currently under consideration; and
(3) Unidentified sources.
This appendix summarizes key features of refined air quality models preferred for specific regulatory applications. For each model, information is provided on availability, approximate cost, regulatory use,
Many of these models have been subjected to a performance evaluation using comparisons with observed air quality data. A summary of such comparisons for models contained in this appendix is included in Moore et al. (1982). Where possible, several of the models contained herein have been subjected to evaluation exercises, including (1) statistical performance tests recommended by the American Meteorological Society and (2) peer scientific reviews. The models in this appendix have been selected on the basis of the results of the model evaluations, experience with previous use, familiarity of the model to various air quality programs, and the costs and resource requirements for use.
All models and user's documentation in this appendix are available from: Computer Products, National Technical Information Service (NTIS), U.S. Department of Commerce, Springfield, VA 22161, Phone: (703) 487-4650. In addition, model codes and selected, abridged user's guides are available from the Support Center for Regulatory Air Models Bulletin Board System
Schulman, Lloyd L. and Joseph S. Scire, 1980. Buoyant Line and Point Source (BLP) Dispersion Model User's Guide. Document P-7304B. Environmental Research and Technology, Inc., Concord, MA. (NTIS No. PB 81-164642)
The computer code is available on the Support Center for Regulatory Models Bulletin Board System and also on diskette (as PB 90-500281) from the National Technical Information Service (see section A.0).
BLP is a Gaussian plume dispersion model designed to handle unique modeling problems associated with aluminum reduction plants, and other industrial sources where plume rise and downwash effects from stationary line sources are important.
The BLP model is appropriate for the following applications:
Aluminum reduction plants which contain buoyant, elevated line sources;
Rural areas;
Transport distances less than 50 kilometers;
Simple terrain; and
One hour to one year averaging times.
The following options should be selected for regulatory applications:
Rural (IRU=1) mixing height option;
Default (no selection) for plume rise wind shear (LSHEAR), transitional point source plume rise (LTRANS), vertical potential temperature gradient (DTHTA), vertical wind speed power law profile exponents (PEXP), maximum variation in number of stability classes per hour (IDELS), pollutant decay (DECFAC), the constant in Briggs' stable plume rise equation (CONST2), constant in Briggs' neutral plume rise equation (CONST3), convergence criterion for the line source calculations (CRIT), and maximum iterations allowed for line source calculations (MAXIT); and
Terrain option (TERAN) set equal to 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
For other applications, BLP can be used if it can be demonstrated to give the same estimates as a recommended model for the same application, and will subsequently be executed in that mode.
BLP can be used on a case-by-case basis with specific options not available in a recommended model if it can be demonstrated, using the criteria in section 3.2, that the model is more appropriate for a specific application.
Source data: point sources require stack location, elevation of stack base, physical stack height, stack inside diameter, stack gas exit velocity, stack gas exit temperature, and pollutant emission rate. Line sources require coordinates of the end points of the line, release height, emission rate, average line source width, average building width, average spacing between buildings, and average line source buoyancy parameter.
Meteorological data: hourly surface weather data from punched cards or from the preprocessor program RAMMET which provides hourly stability class, wind direction, wind speed, temperature, and mixing height.
Receptor data: locations and elevations of receptors, or location and size of receptor grid or request automatically generated receptor grid.
Printed output (from a separate post-processor program) includes:
Total concentration or, optionally, source contribution analysis; monthly and annual frequency distributions for 1-, 3-, and 24-hour average concentrations; tables of 1-, 3-, -and 24-hour average concentrations at each receptor; table of the annual (or length of run) average concentrations at each receptor;
Five highest 1-, 3-, and 24-hour average concentrations at each receptor; and
Fifty highest 1-, 3-, and 24-hour concentrations over the receptor field.
BLP is a gaussian plume model.
BLP may be used to model primary pollutants. This model does not treat settling and deposition.
BLP treats up to 50 point sources, 10 parallel line sources, and 100 receptors arbitrarily located.
User-input topographic elevation is applied for each stack and each receptor.
BLP uses plume rise formulas of Schulman and Scire (1980).
Vertical potential temperature gradients of 0.02 Kelvin per meter for E stability and 0.035 Kelvin per meter are used for stable plume rise calculations. An option for user input values is included.
Transitional rise is used for line sources.
Option to suppress the use of transitional plume rise for point sources is included.
The building downwash algorithm of Schulman and Scire (1980) is used.
Constant, uniform (steady-state) wind is assumed for an hour.
Straight line plume transport is assumed to all downwind distances.
Wind speeds profile exponents of 0.10, 0.15, 0.20, 0.25, 0.30, and 0.30 are used for stability classes A through F, respectively. An option for user-defined values and an option to suppress the use of the wind speed profile feature are included.
Vertical wind speed is assumed equal to zero.
Rural dispersion coefficients are from Turner (1969), with no adjustment made for variations in surface roughness or averaging time.
Six stability classes are used.
Rural dispersion coefficients are from Turner (1969), with no adjustment made for variations in surface roughness.
Six stability classes are used.
Mixing height is accounted for with multiple reflections until the vertical plume standard deviation equals 1.6 times the mixing height; uniform mixing is assumed beyond that point.
Perfect reflection at the ground is assumed.
Chemical transformations are treated using linear decay. Decay rate is input by the user.
Physical removal is not explicitly treated.
Schulman, L.L. and J.S. Scire, 1980. Buoyant Line and Point Source (BLP) Dispersion Model User's Guide, P-7304B. Environmental Research and Technology, Inc., Concord, MA.
Scire, J.S. and L.L. Schulman, 1981. Evaluation of the BLP and ISC Models with SF
Benson, Paul E., 1979. CALINE3—A Versatile Dispersion Model for Predicting Air Pollutant Levels Near Highways and Arterial Streets. Interim Report, Report Number FHWA/CA/TL-79/23. Federal Highway Administration, Washington, D.C. (NTIS No. PB 80-220841)
The CALINE3 model is available on diskette (as PB 95-502712) from NTIS. The source code and user's guide are also available on the Support Center for Regulatory Models Bulletin Board System (see section A.0).
CALINE3 can be used to estimate the concentrations of nonreactive pollutants from highway traffic. This steady-state Gaussian model can be applied to determine air pollution concentrations at receptor locations downwind of “at-grade,” “fill,” “bridge,” and “cut section” highways located in relatively uncomplicated terrain. The model is applicable for any wind direction, highway orientation, and receptor location. The model has adjustments for averaging time and surface roughness, and can handle up to 20 links and 20 receptors. It also contains an
CALINE-3 is appropriate for the following applications:
Highway (line) sources;
Urban or rural areas;
Simple terrain;
Transport distances less than 50 kilometers; and
One-hour to 24-hour averaging times.
Source data: up to 20 highway links classed as “at-grade,” “fill” “bridge,” or “depressed”; coordinates of link end points; traffic volume; emission factor; source height; and mixing zone width.
Meteorological data: wind speed, wind angle (measured in degrees clockwise from the Y axis), stability class, mixing height, ambient (background to the highway) concentration of pollutant.
Receptor data: coordinates and height above ground for each receptor. c.
Printed output includes concentration at each receptor for the specified meteorological condition.
CALINE-3 is a Gaussian plume model.
CALINE-3 may be used to model primary pollutants.
Up to 20 highway links are treated.
CALINE-3 applies user input location and emission rate for each link. User-input receptor locations are applied.
Plume rise is not treated.
User-input hourly wind speed and direction are applied.
Constant, uniform (steady-state) wind is assumed for an hour.
Vertical wind speed is assumed equal to zero.
Six stability classes are used.
Rural dispersion coefficients from Turner (1969) are used, with adjustment for roughness length and averaging time.
Initial traffic-induced dispersion is handled implicitly by plume size parameters.
Six stability classes are used.
Empirical dispersion coefficients from Benson (1979) are used including an adjustment for roughness length.
Initial traffic-induced dispersion is handled implicitly by plume size parameters.
Adjustment for averaging time is included.
Not treated.
Optional deposition calculations are included.
Bemis, G.R. et al., 1977. Air Pollution and Roadway Location, Design, and Operation—Project Overview. FHWA-CA-TL-7080-77-25, Federal Highway Administration, Washington, D.C.
Cadle, S.H. et al., 1976. Results of the General Motors Sulfate Dispersion Experiment, GMR-2107. General Motors Research Laboratories, Warren, MI.
Dabberdt, W.F., 1975. Studies of Air Quality on and Near Highways, Project 2761. Stanford Research Institute, Menlo Park, CA.
Irwin, J.S., T. Chico and J. Catalano, 1985. CDM 2.0—Climatological Dispersion Model—User's Guide. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 86-136546)
The source code and user's guide is available on the Support Center for Regulatory Models Bulletin Board System. The computer code is also available on diskette (as PB 90-500406) from the National Technical Information Service (see section A.0).
CDM is a climatological steady-state Gaussian plume model for determining long-term (seasonal or annual) arithmetic average pollutant concentrations at any ground-level receptor in an urban area.
CDM is appropriate for the following applications:
Point and area sources;
Urban areas;
Flat terrain;
Transport distances less than 50 kilometers;
Long term averages over one month to one year or longer.
The following option should be selected for regulatory applications:
Set the regulatory “default option” (NDEF=1) which automatically selects stack tip downwash, final plume rise, buoyancy-induced dispersion (BID), and the appropriate wind profile exponents.
Enter “0” for pollutant half-life for all pollutants except for SO
Source data: location, average emissions rates and heights of emissions for point and area sources. Point source data requirements also include stack gas temperature, stack gas exit velocity, and stack inside diameter for plume rise calculations for point sources.
Meteorological data: stability wind rose (STAR deck day/night version), average mixing height and wind speed in each stability category, and average air temperature.
Receptor data: cartesian coordinates of each receptor.
Printed output includes:
Average concentrations for the period of the stability wind rose data (arithmetic mean only) at each receptor, and
Optional point and area concentration rose for each receptor.
CDM is a climatological Gaussian plume model.
CDM may be used to model primary pollutants. Settling and deposition are not treated.
CDM applies user-specified locations for all point sources and receptors.
Area sources are input as multiples of a user-defined unit area source grid size.
User specified release heights are applied for individual point sources and the area source grid.
Actual separation between each source-receptor pair is used.
The user may select a single height at or above ground level that applies to all receptors.
No terrain differences between source and receptor are treated.
CDM uses Briggs (1969, 1971, 1975) plume rise equations. Optionally a plume rise-wind speed product may be input for each point source.
Stack tip downwash equation from Briggs (1974) is preferred for regulatory use. The Bjorklund and Bowers (1982) equation is also included.
No plume rise is calculated for area sources.
Does not treat fumigation or building downwash.
Wind data are input as a stability wind rose (joint frequency distribution of 16 wind directions, 6 wind classes, and 5 stability classes).
Wind speed profile exponents for the urban case (Irwin, 1979; EPA, 1980) are used, assuming the anemometer height is at 10.0 meters.
Vertical wind speed is assumed equal to zero.
Pollutants are assumed evenly distributed across a 22.5 or 10.0 degree sector.
There are seven vertical dispersion parameter schemes, but the following is recommended for regulatory applications:
• Briggs-urban (Gifford, 1976).
Mixing height has no effect until dispersion coefficient equals 0.8 times the mixing height; uniform vertical mixing is assumed beyond that point.
Buoyancy-induced dispersion (Pasquill, 1976) is included as an option. Perfect reflection is assumed at the ground.
Chemical transformations are treated using exponential decay. Half-life is input by the user.
Physical removal is not explicitly treated.
Busse, A.D. and J.R. Zimmerman, 1973. User's Guide for the Climatological Dispersion Model—Appendix E. EPA Publication No. EPA/R4-73-024. Office of Research and Development, Research Triangle Park, NC.
Irwin, J.S. and T.M. Brown, 1985. A Sensitivity Analysis of the Treatment of Area Sources by the Climatological Dispersion Model. Journal of Air Pollution Control Association, 35: 359-364.
Londergan, R., D. Minott, D. Wachter and R. Fizz, 1983. Evaluation of Urban Air Quality Simulation Models, EPA Publication No. EPA-450/4-83-020. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Zimmerman, J.R., 1971. Some Preliminary Results of Modeling from the Air Pollution Study of Ankara, Turkey, Proceedings of the Second Meeting of the Expert Panel on Air Pollution Modeling, NATO Committee on the Challenges of Modern Society, Paris, France.
Zimmerman, J.R., 1972. The NATO/CCMS Air Pollution Study of St. Louis, Missouri. Presented at the Third Meeting of the Expert Panel on Air Pollution Modeling, NATO Committee on the Challenges of Modern Society, Paris, France.
Turner, D.B. and J.H. Novak, 1978. User's Guide for RAM. Publication No. EPA-600/8-78-016, Vol. a and b. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS Nos. PB 294791 and PB 294792)
Catalano, J.A., D.B. Turner and H. Novak, 1987. User's Guide for RAM—Second Edition. U.S. Environmental Protection Agency, Research Triangle Park, NC.
The source code and user's guide is available on the Support Center for Regulatory Models Bulletin Board System. The computer code is also available on diskette (as PB 90-500315) from the National Technical Information Service (see section A.0).
RAM is a steady-state Gaussian plume model for estimating concentrations of relatively stable pollutants, for averaging times from an hour to a day, from point and area sources in a rural or urban setting. Level terrain is assumed. Calculations are performed for each hour.
RAM is appropriate for the following applications:
Point and area sources;
Urban areas;
Flat terrain;
Transport distances less than 50 kilometers; and
One hour to one year averaging times.
The following options should be selected for regulatory applications:
Set the regulatory “default option” to automatically select stack tip downwash, final plume rise, buoyancy-induced dispersion (BID), the new treatment for calms, the appropriate wind profile exponents, and the appropriate value for pollutant half-life.
Source data: point sources require location, emission rate, physical stack height, stack gas exit velocity, stack inside diameter and stack gas temperature. Area sources require location, size, emission rate, and height of emissions.
Meteorological data: hourly surface weather data from the preprocessor program RAMMET which provides hourly stability class, wind direction, wind speed, temperature, and mixing height. Actual anemometer height (a single value) is also required.
Receptor data: coordinates of each receptor. Options for automatic placement of receptors near expected concentration maxima, and a gridded receptor array are included.
Printed output optionally includes:
One to 24-hour and annual average concentrations at each receptor,
Limited individual source contribution list, and
Highest through fifth highest concentrations at each receptor for period, with the highest and high, second-high values flagged.
RAM is a Gaussian plume model.
RAM may be used to model primary pollutants. Settling and deposition are not treated.
RAM applies user-specified locations for all point sources and receptors. Area sources are input as multiples of a user-defined unit area source grid size.
User specified stack heights are applied for individual point sources.
Up to 3 effective release heights may be specified for the area sources. Area source release heights are assumed to be appropriate for a 5 meter per second wind and to be inversely proportional to wind speed.
Actual separation between each source-receptor pair is used.
All receptors are assumed to be at the same height at or above ground level.
No terrain differences between source and receptor are accounted for.
RAM uses Briggs (1969, 1971, 1975) plume rise equations for final rise.
Stack tip downwash equation from Briggs (1974) is used.
A user supplied fraction of the area source height is treated as the physical height. The
Fumigation and building downwash are not treated.
Constant, uniform (steady state) wind is assumed for an hour.
Straight line plume transport is assumed to all downwind distances.
Separate wind speed profile exponents (Irwin, 1979; EPA, 1980) for urban cases are used.
Vertical wind speed is assumed equal to zero.
Urban dispersion coefficients from Briggs (Gifford, 1976) are used.
Buoyancy-induced dispersion (Pasquill, 1976) is included.
Six stability classes are used.
Urban dispersion coefficients from Briggs (Gifford, 1976) are used.
Buoyancy-induced dispersion (Pasquill, 1976) is included.
Six stability classes are used.
Mixing height is accounted for with multiple reflections until the vertical plume standard deviation equals 1.6 times the mixing height; uniform vertical mixing is assumed beyond that point.
Perfect reflection is assumed at the ground.
Chemical transformations are treated using exponential decay. Half-life is input by the user.
Physical removal is not explicitly treated.
Ellis, H., P. Lou, and G. Dalzell, 1980. Comparison Study of Measured and Predicted Concentrations with the RAM Model at Two Power Plants Along Lake Erie. Second Joint Conference on Applications of Air Pollution Meteorology, New Orleans, LA.
Environmental Research and Technology, 1980. SO
Guldberg, P.H. and C.W. Kern, 1978. A Comparison Validation of the RAM and PTMTP Models for Short-Term Concentrations in Two Urban Areas. Journal of Air Pollution Control Association, 28: 907-910.
Hodanbosi, R.R. and L.K. Peters, 1981. Evaluation of RAM Model for Cleveland, Ohio. Journal of Air Pollution Control Association, 31: 253-255.
Kennedy, K.H., R.D. Siegel and M.P. Steinberg, 1981. Case-Specific Evaluation of the RAM Atmospheric Dispersion Model in an Urban Area. 74th Annual Meeting of the American Institute of Chemical Engineers, New Orleans, LA.
Kummier, R.H., B. Cho, G. Roginski, R. Sinha and A. Greenburg, 1979. A Comparative Validation of the RAM and Modified SAI Models for Short Term SO
Londergan, R.J., N.E. Bowne, D.R. Murray, H. Borenstein and J. Mangano, 1980. An Evaluation of Short-Term Air Quality Models Using Tracer Study Data. Report No. 4333, American Petroleum Institute, Washington, D.C.
Londergan, R., D. Minott, D. Wackter and R. Fizz, 1983. Evaluation of Urban Air Quality Simulation Models. EPA Publication No. EPA-450/4-83-020. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Morgenstern, P., M.J. Geraghty, and A. McKnight, 1979. A Comparative Study of the RAM (Urban) and RAMR (Rural) Models for Short-term SO
Ruff, R.E., 1980. Evaluation of the RAM Using the RAPS Data Base. Contract 68-02-2770, SRI International, Menlo Park, CA.
Environmental Protection Agency, 1995. User's Guide for the Industrial Source Complex (ISC3) Dispersion Models, Volumes 1 and 2. EPA Publication Nos. EPA-454/B-95-003a & b. Environmental Protection Agency, Research Triangle Park, NC. (NTIS Nos. PB 95-222741 and PB 95-222758, respectively)
The model code is available on the Support Center for Regulatory Air Models Bulletin Board System. ISCST3 (as PB 96-502000) and ISCLT3 (PB 96-502018) are also available on diskette from the National Technical Information Service (see section A.0).
The ISC3 model is a steady-state Gaussian plume model which can be used to assess pollutant concentrations from a wide variety of sources associated with an industrial source complex. This model can account for the following: settling and dry deposition of particles; downwash; area, line and volume
ISC3 is appropriate for the following applications:
• Industrial source complexes;
• Rural or urban areas;
• Flat or rolling terrain;
• Transport distances less than 50 kilometers;
• 1-hour to annual averaging times; and
• Continuous toxic air emissions.
The following options should be selected for regulatory applications: For short term or long term modeling, set the regulatory “default option”; i.e., use the keyword DFAULT, which automatically selects stack tip downwash, final plume rise, buoyancy induced dispersion (BID), the vertical potential temperature gradient, a treatment for calms, the appropriate wind profile exponents, the appropriate value for pollutant half-life, and a revised building wake effects algorithm; set the “rural option” (use the keyword RURAL) or “urban option” (use the keyword URBAN); and set the “concentration option” (use the keyword CONC).
Source data: location, emission rate, physical stack height, stack gas exit velocity, stack inside diameter, and stack gas temperature. Optional inputs include source elevation, building dimensions, particle size distribution with corresponding settling velocities, and surface reflection coefficients.
Meteorological data: ISCST3 requires hourly surface weather data from the preprocessor program RAMMET, which provides hourly stability class, wind direction, wind speed, temperature, and mixing height. For ISCLT3, input includes stability wind rose (STAR deck), average afternoon mixing height, average morning mixing height, and average air temperature.
Receptor data: coordinates and optional ground elevation for each receptor.
Printed output options include:
• Program control parameters, source data, and receptor data;
• Tables of hourly meteorological data for each specified day;
• “N”-day average concentration or total deposition calculated at each receptor for any desired source combinations;
• Concentration or deposition values calculated for any desired source combinations at all receptors for any specified day or time period within the day;
• Tables of highest and second highest concentration or deposition values calculated at each receptor for each specified time period during a(n) “N”-day period for any desired source combinations, and tables of the maximum 50 concentration or deposition values calculated for any desired source combinations for each specified time period.
ISC3 is a Gaussian plume model. It has been revised to perform a double integration of the Gaussian plume kernel for area sources.
ISC3 may be used to model primary pollutants and continuous releases of toxic and hazardous waste pollutants. Settling and deposition are treated.
ISC3 applies user-specified locations for point, line, area and volume sources, and user-specified receptor locations or receptor rings.
User input topographic evaluation for each receptor is used. Elevations above stack top are reduced to the stack top elevation, i.e., “terrain chopping”.
User input height above ground level may be used when necessary to simulate impact at elevated or “flag pole” receptors, e.g., on buildings.
Actual separation between each source-receptor pair is used.
ISC3 uses Briggs (1969, 1971, 1975) plume rise equations for final rise.
Stack tip downwash equation from Briggs (1974) is used.
Revised building wake effects algorithm is used. For stacks higher than building height plus one-half the lesser of the building height or building width, the building wake algorithm of Huber and Snyder (1976) is used. For lower stacks, the building wake algorithm of Schulman and Scire (Schulman and Hanna, 1986) is used, but stack tip downwash and BID are not used.
For rolling terrain (terrain not above stack height), plume centerline is horizontal at height of final rise above source.
Fumigation is not treated.
Constant, uniform (steady-state) wind is assumed for each hour.
Straight line plume transport is assumed to all downwind distances.
Separate wind speed profile exponents (Irwin, 1979; EPA, 1980) for both rural and urban cases are used.
An optional treatment for calm winds is included for short term modeling.
Vertical wind speed is assumed equal to zero.
Rural dispersion coefficients from Turner (1969) are used, with no adjustments for surface roughness or averaging time.
Urban dispersion coefficients from Briggs (Gifford, 1976) are used.
Buoyancy induced dispersion (Pasquill, 1976) is included.
Six stability classes are used.
Rural dispersion coefficients from Turner (1969) are used, with no adjustments for surface roughness.
Urban dispersion coefficients from Briggs (Gifford, 1976) are used.
Buoyancy induced dispersion (Pasquill, 1976) is included.
Six stability classes are used.
Mixing height is accounted for with multiple reflections until the vertical plume standard deviation equals 1.6 times the mixing height; uniform vertical mixing is assumed beyond that point.
Perfect reflection is assumed at the ground.
Chemical transformations are treated using exponential decay. Time constant is input by the user.
Dry deposition effects for particles are treated using a resistance formulation in which the deposition velocity is the sum of the resistances to pollutant transfer within the surface layer of the atmosphere, plus a gravitational settling term (EPA, 1994), based on the modified surface depletion scheme of Horst (1983).
Bowers, J.F. and A.J. Anderson, 1981. An Evaluation Study for the Industrial Source Complex (ISC) Dispersion Model, EPA Publication No. EPA-450/4-81-002. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Bowers, J.F., A.J. Anderson and W.R. Hargraves, 1982. Tests of the Industrial Source Complex (ISC) Dispersion Model at the Armco Middletown, Ohio Steel Mill. EPA Publication No. EPA-450/4-82-006. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Environmental Protection Agency, 1992. Comparison of a Revised Area Source Algorithm for the Industrial Source Complex Short Term Model and Wind Tunnel Data. EPA Publication No. EPA-454/R-92-014. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 93-226751)
Environmental Protection Agency, 1992. Sensitivity Analysis of a Revised Area Source Algorithm for the Industrial Source Complex Short Term Model. EPA Publication No. EPA-454/R-92-015. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 93-226769)
Environmental Protection Agency, 1992. Development and Evaluation of a Revised Area Source Algorithm for the Industrial source complex Long Term Model. EPA Publication No. EPA-454/R-92-016. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 93-226777)
Environmental Protection Agency, 1994. Development and Testing of a Dry Deposition Algorithm (Revised). EPA Publication No. EPA-454/R-94-015. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 94-183100)
Scire, J.S. and L.L. Schulman, 1981. Evaluation of the BLP and ISC Models with SF
Schulman, L.L. and S.R. Hanna, 1986. Evaluation of Downwash Modification to the Industrial Source Complex Model. Journal of the Air Pollution Control Association, 36: 258-264.
Environmental Protection Agency, 1990. User's Guide for the Urban Airshed Model, Volume I-VIII. EPA Publication Nos. EPA-450/4-90-007a-c, d(R), e-g, and EPA-454/B-93-004, respectively. U.S. Environmental Protection Agency, Research Triangle Park, NC (NTIS Nos. PB 91-131227, PB 91-131235, PB 91-131243, PB 93-122380, PB 91-131268, PB 92-145382, and PB 92-224849, respectively, for Vols. I-VII).
The model code is available on the Support Center for Regulatory Air Models Bulletin Board System (see section A.0).
UAM is an urban scale, three dimensional, grid type numerical simulation model. The model incorporates a condensed photochemical kinetics mechanism for urban atmospheres. The UAM is designed for computing ozone (O
UAM is appropriate for the following applications: urban areas having significant ozone attainment problems and one hour averaging times.
UAM has many options but no specific recommendations can be made at this time on all options. The reviewing agency should be consulted on selection of options to be used in regulatory applications.
Source data: gridded, hourly emissions of PAR, OLE, ETH, XYL, TOL, ALD2, FORM, ISOR, ETOTH, MEOH, CO, NO, and NO
Meteorological data: hourly, gridded, divergence free, u and v wind components for each vertical level; hourly gridded mixing heights and surface temperatures; hourly exposure class; hourly vertical potential temperature gradient above and below the mixing height; hourly surface atmospheric pressure; hourly water mixing ratio; and gridded surface roughness lengths.
Air quality data: concentration of all carbon bond 4 species at the beginning of the simulation for each grid cell; and hourly concentrations of each pollutant at each level along the inflow boundaries and top boundary of the modeling region.
Other data requirements are: hourly mixed layer average, NO
Printed output includes:
• Gridded instantaneous concentration fields at user-specified time intervals for user-specified pollutants and grid levels;
• Gridded time-average concentration fields for user-specified time intervals, pollutants, and grid levels.
UAM is a three dimensional, numerical, photochemical grid model.
UAM may be used to model ozone (O
Low-level area and point source emissions are specified within each surface grid cell. Emissions from major point sources are placed within cells aloft in accordance with calculated effective plume heights.
Hourly average concentrations of each pollutant are calculated for all grid cells at each vertical level.
Plume rise is calculated for major point sources using relationships recommended by Briggs (1971).
See Input Requirements.
Calculated at each vertical grid cell interface from the mass continuity relationship using the input gridded horizontal wind field.
Horizontal eddy diffusivity is set to a user specified constant value (nominally 50 m
Vertical eddy diffusivities for unstable and neutral conditions calculated using relationships of Lamb
UAM employs a simplified version of the Carbon-Bond IV Mechanism (CBM-IV) developed by Gery
Dry deposition of ozone and other pollutant species are calculated. Vegetation (scaling) factors are applied to the reference surface uptake resistance of each species depending on land use type.
Builtjes, P.J.H., K.D. van der Hurt and S.D. Reynolds, 1982. Evaluation of the Performance of a Photochemical Dispersion Model in Practical Applications. 13th International Technical Meeting on Air Pollution Modeling and Its Application, Ile des Embiez, France.
Cole, H.S., D.E. Layland, G.K. Moss and C.F. Newberry, 1983. The St. Louis Ozone Modeling Project. EPA Publication No. EPA-450/4-83-019. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Dennis, R.L., M.W. Downton and R.S. Keil, 1983. Evaluation of Performance Measures for an Urban Photochemical Model. EPA Publication No. EPA-450/4-83-021. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Haney, J.L. and T.N. Braverman, 1985. Evaluation and Application of the Urban Airshed Model in the Philadelphia Air Quality Control Region. EPA Publication No. EPA-450/4-85-003. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Layland, D.E. and H.S. Cole, 1983. A Review of Recent Applications of the SAI Urban Airshed Model. EPA Publication No. EPA-450/4-84-004. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Layland, D.E., S.D. Reynolds, H. Hogo and W.R. Oliver, 1983. Demonstration of Photochemical Grid Model Usage for Ozone Control Assessment. 76th Annual Meeting of the Air Pollution Control Association, Atlanta, GA.
Morris, R.E. et al., 1990. Urban Airshed Model Study of Five Cities. EPA Publication No. EPA-450/4-90-006a-g. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Reynolds, S.D., H. Hogo, W.R. Oliver and L.E. Reid, 1982. Application of the SAI Airshed Model to the Tulsa Metropolitan Area, SAI No. 82004. Systems Applications, Inc., San Rafael, CA.
Schere, K.L. and J.H. Shreffler, 1982. Final Evaluation of Urban-Scale Photochemical Air Quality Simulation Models. EPA Publication No. EPA-600/3-82-094. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Seigneur C., T.W. Tesche, C.E. Reid, P.M. Roth, W.R. Oliver and J.C. Cassmassi, 1981. The Sensitivity of Complex Photochemical Model Estimates to Detail In Input Information, Appendix A—A Compilation of Simulation Results. EPA Publication No. EPA-450/4-81-031b. U.S. Environmental Protection Agency, Research Triangle Park, NC.
South Coast Air Quality Management District, 1989. Air Quality Management Plan—Appendix V-R (Urban Airshed Model Performance Evaluation). El Monte, CA.
Stern, R. and B. Scherer, 1982. Simulation of a Photochemical Smog Episode in the Rhine-Ruhr Area with a Three Dimensional Grid Model. 13th International Technical Meeting on Air Pollution Modeling and Its Application, Ile des Embiez, France.
Tesche, T.W., C. Seigneur, L.E. Reid, P.M. Roth, W.R. Oliver and J.C. Cassmassi, 1981. The Sensitivity of Complex Photochemical Model Estimates to Detail in Input Information. EPA Publication No. EPA-450/4-81-031a. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Tesche, T.W., W.R. Oliver, H. Hogo, P. Saxeena and J.L. Haney, 1983. Volume IV—Assessment of NO
Tesche, T.W., W.R. Oliver, H. Hogo, P. Saxeena and J.L. Haney, 1983. Volume IV—Assessment of NO
Tesche, T.W., 1988. Accuracy of Ozone Air Quality Models. Journal of Environmental Engineering, 114(4): 739-752.
DiCristofaro, D.C. and S.R. Hanna, 1989. OCD: The Offshore and Coastal Dispersion Model, Version 4. Volume I: User's Guide, and Volume II: Appendices. Sigma Research Corporation, Westford, MA. (NTIS Nos. PB 93-144384 and PB 93-144392)
This model code is available on the Support Center for Regulatory Air Models Bulletin Board System and also on diskette (as PB 91-505230) from the National Technical Information Service (see section A.0).
Minerals Management Service, Attn: Mr. Dirk Herkhof, Parkway Atrium Building, 381 Elden Street, Herndon, VA 22070-4817, Phone: (703) 787-1735.
OCD is a straight-line Gaussian model developed to determine the impact of offshore emissions from point, area or line sources on the air quality of coastal regions. OCD incorporates overwater plume transport and dispersion as well as changes that occur as the plume crosses the shoreline. Hourly meteorological data are needed from both offshore and onshore locations. These include water surface temperature, overwater air temperature, mixing height, and relative humidity.
Some of the key features include platform building downwash, partial plume penetration into elevated inversions, direct use of turbulence intensities for plume dispersion, interaction with the overland internal boundary layer, and continuous shoreline fumigation.
OCD has been recommended for use by the Minerals Management Service for emissions
Source data: point, area or line source location, pollutant emission rate, building height, stack height, stack gas temperature, stack inside diameter, stack gas exit velocity, stack angle from vertical, elevation of stack base above water surface and gridded specification of the land/water surfaces. As an option, emission rate, stack gas exit velocity and temperature can be varied hourly.
Meteorological data (over water): wind direction, wind speed, mixing height, relative humidity, air temperature, water surface temperature, vertical wind direction shear (optional), vertical temperature gradient (optional), turbulence intensities (optional).
Meteorological data (over land): wind direction, wind speed, temperature, stability class, mixing height.
Receptor data: location, height above local ground-level, ground-level elevation above the water surface.
All input options, specification of sources, receptors and land/Water map including locations of sources and receptors.
Summary tables of five highest concentrations at each receptor for each averaging period, and average concentration for entire run period at each receptor.
Optional case study printout with hourly plume and receptor characteristics. Optional table of annual impact assessment from non-permanent activities.
Concentration files written to disk or tape can be used by ANALYSIS postprocessor to produce the highest concentrations for each receptor, the cumulative frequency distributions for each receptor, the tabulation of all concentrations exceeding a given threshold, and the manipulation of hourly concentration files.
OCD is a Gaussian plume model constructed on the framework of the MPTER model.
OCD may be used to model primary pollutants. Settling and deposition are not treated.
Up to 250 point sources, 5 area sources, or 1 line source and 180 receptors may be used.
Receptors and sources are allowed at any location.
The coastal configuration is determined by a grid of up to 3600 rectangles. Each element of the grid is designated as either land or water to identify the coastline.
As in MPTER, the basic plume rise algorithms are based on Briggs' recommendations.
Momentum rise includes consideration of the stack angle from the vertical.
The effect of drilling platforms, ships, or any overwater obstructions near the source are used to decrease plume rise using a revised platform downwash algorithm based on laboratory experiments.
Partial plume penetration of elevated inversions is included using the suggestions of Briggs (1975) and Weil and Brower (1984).
Continuous shoreline fumigation is parametrized using the Turner method where complete vertical mixing through the thermal internal boundary layer (TIBL) occurs as soon as the plume intercepts the TIBL.
Constant, uniform wind is assumed for each hour.
Overwater wind speed can be estimated from overland wind speed using relationship of Hsu (1981).
Wind speed profiles are estimated using similarity theory (Businger, 1973). Surface layer fluxes for these formulas are calculated from bulk aerodynamic methods.
Vertical wind speed is assumed equal to zero.
Lateral turbulence intensity is recommended as a direct estimate of horizontal dispersion. If lateral turbulence intensity is not available, it is estimated from boundary layer theory. For wind speeds less than 8 m/s, lateral turbulence intensity is assumed inversely proportional to wind speed.
Horizontal dispersion may be enhanced because of obstructions near the source. A virtual source technique is used to simulate the initial plume dilution due to downwash.
Formulas recommended by Pasquill (1976) are used to calculate buoyant plume enhancement and wind direction shear enhancement.
At the water/land interface, the change to overland dispersion rates is modeled using a virtual source. The overland dispersion rates can be calculated from either lateral turbulence intensity or Pasquill-Gifford curves. The change is implemented where the plume intercepts the rising internal boundary layer.
Observed vertical turbulence intensity is not recommended as a direct estimate of vertical dispersion. Turbulence intensity should be estimated from boundary layer theory as default in the model. For very stable conditions, vertical dispersion is also a function of lapse rate.
Vertical dispersion may be enhanced because of obstructions near the source. A virtual source technique is used to simulate the initial plume dilution due to downwash.
Formulas recommended by Pasquill (1976) are used to calculate buoyant plume enhancement.
At the water/land interface, the change to overland dispersion rates is modeled using a virtual source. The overland dispersion rates can be calculated from either vertical turbulence intensity or the Pasquill-Gifford coefficients. The change is implemented where the plume intercepts the rising internal boundary layer.
Chemical transformations are treated using exponential decay. Different rates can be specified by month and by day or night.
Physical removal is also treated using exponential decay.
DiCristofaro, D.C. and S.R. Hanna, 1989. OCD: The Offshore and Coastal Dispersion Model. Volume I: User's Guide. Sigma Research Corporation, Westford, MA.
Hanna, S.R., L.L. Schulman, R.J. Paine and J.E. Pleim, 1984. The Offshore and Coastal Dispersion (OCD) Model User's Guide, Revised. OCS Study, MMS 84-0069. Environmental Research & Technology, Inc., Concord, MA. (NTIS No. PB 86-159803)
Hanna, S.R., L.L. Schulman, R.J. Paine, J.E. Pleim and M. Baer, 1985. Development and Evaluation of the Offshore and Coastal Dispersion (OCD) Model. Journal of the Air Pollution Control Association, 35: 1039-1047.
Hanna, S.R. and D.C. DiCristofaro, 1988. Development and Evaluation of the OCD/API Model. Final Report, API Pub. 4461, American Petroleum Institute, Washington, D.C.
Segal, H.M., 1991. “EDMS—Microcomputer Pollution Model for Civilian Airports and Air Force Bases: User's Guide.” FAA Report No. FAA-EE-91-3; USAF Report No. ESL-TR-91-31, Federal Aviation Administration, 800 Independence Avenue, S.W., Washington, D.C. 20591. (NTIS No. ADA 240528)
Segal, H.M. and Hamilton, P.L., 1988. “A Microcomputer Pollution Model for Civilian Airports and Air Force Bases—Model Description.” FAA Report No. FAA-EE-88-4; USAF Report No. ESL-TR-88-53, Federal Aviation Administration, 800 Independence Avenue, S.W., Washington, D.C. 20591. (NTIS No. ADA 199003)
Segal, H.M., 1988. “A Microcomputer Pollution Model for Civilian Airports and Air Force Bases—Model Application and Background.” FAA Report No. FAA-EE-88-5; USAF Report No. ESL-TR-88-55, Federal Aviation Administration, 800 Independence Avenue, S.W., Washington, D.C. 20591. (NTIS No. ADA 199794)
EDMS is available for $40 from: Federal Aviation Administration, Attn: Ms. Diana Liang, AEE-120, 800 Independence Avenue, S.W., Washington, D.C. 20591, Phone: (202) 267-3494.
EDMS is a combined emissions/dispersion model for assessing pollution at civilian airports and military air bases. This model, which was jointly developed by the Federal Aviation Administration (FAA) and the United States Air Force (USAF), produces an emission inventory of all airport sources and calculates concentrations produced by these sources at specified receptors. The system stores emission factors for fixed sources such as fuel storage tanks and incinerators and also for mobile sources such as automobiles or aircraft. EDMS incorporates an emissions model to calculate an emission inventory for each airport source and a dispersion model, the Graphical Input Microcomputer Model (GIMM) (Segal, 1983) to calculate pollutant concentrations produced by these sources at specified receptors. The GIMM, which processes point, area, and line sources, also incorporates a special meteorological preprocessor for processing up to one year of National Climatic Data Center (NCDC) hourly data. The model operates in both a screening and refined mode, accepting up to 170 sources and 10 receptors.
EDMS is appropriate for the following applications:
• Cumulative effect of changes in aircraft operations, point source and mobile source emissions at airports or air bases;
• Simple terrain;
• Transport distances less than 50 kilometers; and
• 1-hour to annual averaging times.
All data are entered through a “runtime” version of the Condor data base which is an
Wind speed, wind direction, hourly temperature, and Pasquill-Gifford stability category (P-G) are the meteorological inputs. They can be entered manually through the EDMS data entry screens or automatically through the processing of previously loaded NCDC hourly data.
Printed outputs consist of:
• A monthly and yearly emission inventory report for each source entered; and
• A concentration summing report for up to 8760 hours (one year) of data.
For its emissions inventory calculations, EDMS uses algorithms consistent with the EPA Compilation of Air Pollutant Emission Factors, AP-42. For its dispersion calculations, EDMS uses the GIMM model which is described in reports FAA-EE-88-4 and FAA-EE-88-5, referenced above. GIMM uses a Gaussian plume algorithm.
EDMS inventories and calculates the dispersion of carbon monoxide, nitrogen oxides, sulphur oxides, hydrocarbons, and suspended particles.
Up to 170 sources and 10 receptors can be treated simultaneously. Area sources are treated as a series of lines that are positioned perpendicular to the wind.
Line sources (roadways, runways) are modeled as a series of points. Terrain elevation differences between sources and receptors are neglected.
Receptors are assumed to be at ground level.
Plume rise is calculated for all point sources (heating plants, incinerators, etc.) using Briggs plume rise equations (Catalano, 1986; Briggs, 1969; Briggs, 1971; Briggs, 1972).
Building and stack tip downwash effects are not treated.
Roadway dispersion employs a modification to the Gaussian plume algorithms as suggested by Rao and Keenan (1980) to account for close-in vehicle-induced turbulence.
Steady state winds are assumed for each hour. Winds are assumed to be constant with altitude.
Winds are entered manually by the user or automatically by reading previously loaded NCC annual data files.
Vertical wind speed is assumed to be zero.
Four stability classes are used (P-G classes B through E).
Horizontal dispersion coefficients are computed using a table look-up and linear interpolation scheme. Coefficients are based on Pasquill (1976) as adapted by Petersen (1980).
A modified coefficient table is used to account for traffic-enhanced turbulence near roadways. Coefficients are based upon data included in Rao and Keenan (1980).
Four stability classes are used (P-G classes B through E).
Vertical dispersion coefficients are computed using a table look-up and linear interpolation scheme. Coefficients are based on Pasquill (1976) as adapted by Petersen (1980).
A modified coefficient table is used to account for traffic-enhanced turbulence near roadways. Coefficients are based upon data from Roa and Keenan (1980).
Chemical transformations are not accounted for.
Deposition is not treated.
Segal, H.M. and P.L. Hamilton, 1988. A Microcomputer Pollution Model for Civilian Airports and Air Force Bases—Model Description. FAA Report No. FAA-EE-88-4; USAF Report No. ESL-TR-88-53, Federal Aviation Administration, 800 Independence Avenue, S.W., Washington, D.C. 20591.
Segal, H.M., 1988. A Microcomputer Pollution Model for Civilian Airports and Air Force Bases—Model Application and Background. FAA Report No. FAA-EE-88-5; USAF Report No. ESL-TR-88-55, Federal Aviation Administration, 800 Independence Avenue, S.W., Washington, D.C. 20591.
Perry, S.G., D.J. Burns, L.H. Adams, R.J. Paine, M.G. Dennis, M.T. Mills, D.G.
Paine, R.J., D.G. Strimaitis, M.G. Dennis, R.J. Yamartino, M.T. Mills and E.M. Insley, 1987. User's Guide to the Complex Terrain Dispersion Model, Volume 1. EPA Publication No. EPA-600/8-87-058a. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 88-162169)
This model code is available on the Support Center for Regulatory Air Models Bulletin Board System and also on diskette (as PB 90-504119) from the National Technical Information Service (see section A.0).
CTDMPLUS is a refined point source Gaussian air quality model for use in all stability conditions for complex terrain applications. The model contains, in its entirety, the technology of CTDM for stable and neutral conditions. However, CTDMPLUS can also simulate daytime, unstable conditions, and has a number of additional capabilities for improved user friendliness. Its use of meteorological data and terrain information is different from other EPA models; considerable detail for both types of input data is required and is supplied by preprocessors specifically designed for CTDMPLUS. CTDMPLUS requires the parameterization of individual hill shapes using the terrain preprocessor and the association of each model receptor with a particular hill.
CTDMPLUS is appropriate for the following applications:
• Elevated point sources;
• Terrain elevations above stack top;
• Rural or urban areas;
• Transport distances less than 50 kilometers; and
• One hour to annual averaging times when used with a post-processor program such as CHAVG.
Source data: For each source, user supplies source location, height, stack diameter, stack exit velocity, stack exit temperature, and emission rate; if variable emissions are appropriate, the user supplies hourly values for emission rate, stack exit velocity, and stack exit temperature.
Meteorological data: the user must supply hourly averaged values of wind, temperature and turbulence data for creation of the basic meteorological data file (“PROFILE”). Meteorological preprocessors then create a SURFACE data file (hourly values of mixed layer heights, surface friction velocity, Monin-Obukhov length and surface roughness length) and a RAWINsonde data file (upper air measurements of pressure, temperature, wind direction, and wind speed).
Receptor data: receptor names (up to 400) and coordinates, and hill number (each receptor must have a hill number assigned).
Terrain data: user inputs digitized contour information to the terrain preprocessor which creates the TERRAIN data file (for up to 25 hills).
When CTDMPLUS is run, it produces a concentration file, in either binary or text format (user's choice), and a list file containing a verification of model inputs, i.e.,
• Input meteorological data from “SURFACE” and “PROFILE”
• Stack data for each source
• Terrain information
• Receptor information
• Source-receptor location (line printer map).
In addition, if the case-study option is selected, the listing includes:
• Meteorological variables at plume height
• Geometrical relationships between the source and the hill
• Plume characteristics at each receptor, i.e.,
−> distance in along-flow and cross flow direction
−> effective plume-receptor height difference
−> effective
−> concentration components due to WRAP, LIFT and FLAT.
If the user selects the TOPN option, a summary table of the top 4 concentrations at each receptor is given. If the ISOR option is selected, a source contribution table for every hour will be printed.
A separate disk file of predicted (1-hour only) concentrations (“CONC”) is written if the user chooses this option. Three forms of output are possible:
(1) A binary file of concentrations, one value for each receptor in the hourly sequence as run;
(2) A text file of concentrations, one value for each receptor in the hourly sequence as run; or
(3) A text file as described above, but with a listing of receptor information (names, positions, hill number) at the beginning of the file.
Hourly information provided to these files besides the concentrations themselves includes the year, month, day, and hour information as well as the receptor number with the highest concentration.
CTDMPLUS is a refined steady-state, point source plume model for use in all stability conditions for complex terrain applications.
CTDMPLUS may be used to model non-reactive, primary pollutants.
Up to 40 point sources, 400 receptors and 25 hills may be used. Receptors and sources are allowed at any location. Hill slopes are assumed not to exceed 15°, so that the linearized equation of motion for Boussinesq flow are applicable. Receptors upwind of the impingement point, or those associated with any of the hills in the modeling domain, require separate treatment.
As in CTDM, the basic plume rise algorithms are based on Briggs' (1975) recommendations.
A central feature of CTDMPLUS for neutral/stable conditions is its use of a critical dividing-streamline height (H
The model calculates on an hourly (or appropriate steady averaging period) basis how the plume trajectory (and, in stable/neutral conditions, the shape) is deformed by each hill. Hourly profiles of wind and temperature measurements are used by CTDMPLUS to compute plume rise, plume penetration (a formulation is included to handle penetration into elevated stable layers, based on Briggs (1984)), convective scaling parameters, the value of H
CTDMPLUS does not simulate calm meteorological conditions. Both scalar and vector wind speed observations can be read by the model. If vector wind speed is unavailable, it is calculated from the scalar wind speed. The assignment of wind speed (either vector or scalar) at plume height is done by either:
• Interpolating between observations above and below the plume height, or
• Extrapolating (within the surface layer) from the nearest measurement height to the plume height.
Vertical flow is treated for the plume component above the critical dividing streamline height (H
Horizontal dispersion for stable/neutral conditions is related to the turbulence velocity scale for lateral fluctuations,
Direct estimates of vertical dispersion for stable/neutral conditions are based on observed vertical turbulence intensity, e.g.,
Chemical transformation is not treated by CTDMPLUS.
Physical removal is not treated by CTDMPLUS (complete reflection at the ground/hill surface is assumed).
Burns, D.J., L.H. Adams and S.G. Perry, 1990. Testing and Evaluation of the CTDMPLUS Dispersion Model: Daytime Convective Conditions. Environmental Protection Agency, Research Triangle Park, NC.
Paumier, J.O., S.G. Perry and D.J. Burns, 1990. An Analysis of CTDMPLUS Model Predictions with the Lovett Power Plant Data Base. Environmental Protection Agency, Research Triangle Park, NC.
Paumier, J.O., S.G. Perry and D.J. Burns, 1992. CTDMPLUS: A Dispersion Model for Sources near Complex Topography. Part II: Performance Characteristics. Journal of Applied Meteorology, 31(7): 646-660.
Benson, P.E., 1979. CALINE3—A Versatile Dispersion Model for Predicting Air Pollution Levels Near Highways and Arterial Streets. Interim Report, Report Number FHWA/CA/TL-79/23. Federal Highway Administration, Washington, D.C.
Briggs, G.A., 1969. Plume Rise. U.S. Atomic Energy Commission Critical Review Series,
Briggs, G.A., 1971. Some Recent Analyses of Plume Rise Observations. Proceedings of the Second International Clean Air Congress, edited by H.M. Englund and W.T. Berry. Academic Press, New York, NY.
Briggs, G.A., 1974. Diffusion Estimation for Small Emissions. USAEC Report ATDL-106. U.S. Atomic Energy Commission, Oak Ridge, TN.
Briggs, G.A., 1975. Plume Rise Predictions. Lectures on Air Pollution and Environmental Impact Analyses. American Meteorological Society, Boston, MA, pp. 59-111.
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs. EPA Publication No. EPA-903/9-82-004a and b. U.S. Environmental Protection Agency, Region III, Philadelphia, PA.
Businger, J.A., 1973. Turbulence Transfer in the Atmospheric Surface Layer. Workshop in Micrometeorology. American Meteorological Society, Boston, MA, pp. 67-100.
Businger, J.A. and S.P. Arya, 1974. Height of the Mixed Layer in the Stably Stratified Planetary Boundary Layer. Advances in Geophysics, Vol. 18A, F.N. Frankiel and R.E. Munn (Eds.), Academic Press, New York, NY.
Catalano, J.A., 1986. Addendum to the User's Manual for the Single Source (CRSTER) Model. EPA Publication No. EPA-600/8-86-041. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 87-145843)
Environmental Protection Agency, 1980. Recommendations on Modeling (October 1980 Meetings). Appendix G to: Summary of Comments and Responses on the October 1980 Proposed Revisions to the Guideline on Air Quality Models. Meteorology and Assessment Division, Office of Research and Development, Research Triangle Park, NC.
Gery, M.W., G.Z. Whitten and J.P. Killus, 1988. Development and Testing of CBM-IV for Urban and Regional Modeling. EPA Publication No. EPA-600/3-88-012. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 88-180039)
Gery, M.W., G.Z. Whitten, J.P. Killus and M.C. Dodge, 1989. A Photochemical Kinetics Mechanism for Urban and Regional Scale Computer Modeling. Journal of Geophysical Research, 94: 12,925-12,956.
Gifford, F.A., Jr. 1976. Turbulent Diffusion Typing Schemes—A Review. Nuclear Safety, 17: 68-86.
Horst, T.W., 1983. A Correction to the Gaussian Source-depletion Model. In
Hsu, S.A., 1981. Models for Estimating Offshore Winds from Onshore Meteorological Measurements. Boundary Layer Meteorology, 20: 341-352.
Huber, A.H. and W.H. Snyder, 1976. Building Wake Effects on Short Stack Effluents. Third Symposium on Atmospheric Turbulence, Diffusion and Air Quality, American Meteorological Society, Boston, MA.
Irwin, J.S., 1979. A Theoretical Variation of the Wind Profile Power-Law Exponent as a Function of Surface Roughness and Stability. Atmospheric Environment, 13: 191-194.
Lamb, R.G. et al., 1977. Continued Research in Mesoscale Air Pollution Simulation Modeling—Vol. VI: Further Studies in the Modeling of Microscale Phenomena, Report Number EF77-143. Systems Applications, Inc., San Rafael, CA.
Liu, M.K. et al., 1976. The Chemistry, Dispersion, and Transport of Air Pollutants Emitted from Fossil Fuel Power Plants in California: Data Analysis and Emission Impact Model. Systems Applications, Inc., San Rafael, CA.
Moore, G.E., T.E. Stoeckenius and D.A. Stewart, 1982. A Survey of Statistical Measures of Model Performance and Accuracy for Several Air Quality Model. EPA Publication No. EPA-450/4-83-001. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Pasquill, F., 1976. Atmospheric Dispersion Parameters in Gaussian Plume Modeling Part II. Possible Requirements for Change in the Turner Workbook Values. EPA Publication No. EPA-600/4-76-030b. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Petersen, W.B., 1980. User's Guide for HIWAY-2 A Highway Air Pollution Model. EPA Publication No. EPA-600/8-80-018. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS PB 80-227556)
Rao, T.R. and M.T. Keenan, 1980. Suggestions for Improvement of the EPA-HIWAY Model. Journal of the Air Pollution Control Association, 30: 247-256 (and reprinted as Appendix C in Petersen, 1980).
Segal, H.M., 1983. Microcomputer Graphics in Atmospheric Dispersion Modeling. Journal of the Air Pollution Control Association, 23: 598-600.
Turner, D.B., 1969. Workbook of Atmospheric Dispersion Estimates. PHS Publication No. 999-26. U.S. Environmental Protection Agency, Research Triangle, Park, NC.
Weil, J.C. and R.P. Brower, 1984. An Updated Gaussian Plume Model for Tall Stacks. Journal of the Air Pollution Control Association, 34: 818-827.
This appendix summarizes key features of refined air quality models that may be considered on a case-by-case basis for individual regulatory applications. For each model, information is provided on availability, approximate cost, regulatory use, data input, output format and options, simulation of atmospheric physics and accuracy. The models are listed by name in alphabetical order.
There are three separate conditions under which these models will normally be approved for use:
1. A demonstration can be made that the model produces concentration estimates equivalent to the estimates obtained using a preferred model (e.g., the maximum or high, second-high concentration is within 2% of the estimate using the comparable preferred model);
2. A statistical performance evaluation has been conducted using measured air quality data and the results of that evaluation indicate the model in appendix B performs better for the application than a comparable model in appendix A; and
3. There is no preferred model for the specific application but a refined model is needed to satisfy regulatory requirements.
Any one of these three separate conditions may warrant use of these models. See section 3.2, Use of Alternative Models, for additional details.
Many of these models have been subject to a performance evaluation by comparison with observed air quality data. A summary of such comparisons for models contained in this appendix is included in Moore
A source for some of these models and user's documentation is: Computer Products, National Technical Information Service (NTIS), U.S. Department of Commerce, Springfield, VA 22161, Phone: (703) 487-4650. A number of the model codes and selected, abridged user's guides are also available from the Support Center for Regulatory Air Models Bulletin Board System
Zannetti, P., G. Carboni and R. Lewis, 1985. AVACTA II User's Guide (Release 3). AeroVironment, Inc., Technical Report AV-OM-85/520.
A 3
The AVACTA II model is a Gaussian model in which atmospheric dispersion phenomena are described by the evolution of plume elements, either segments or puffs. The model can be applied for short time (e.g., one day) simulations in both transport and calm conditions.
The user is given flexibility in defining the computational domain, the three-dimensional meteorological and emission input, the receptor locations, the plume rise formulas, the sigma formulas, etc. Without explicit user's specifications, standard default values are assumed.
AVACTA II provides both concentration fields on the user specified receptor points, and dry/wet deposition patterns throughout the domain. The model is particularly oriented to the simulation of the dynamics and transformation of sulfur species (SO
AVACTA II can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. AVACTA II must be executed in the equivalent mode.
AVACTA II can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section
A time-varying input is required at each computational step. Only those data which have changed need to be input by the user.
Source data requirements are: Coordinates, emission rates of primary and secondary pollutants, initial plume sigmas (for non-point sources), exit temperature, exit velocity, stack inside diameter.
Meteorological data requirements are: surface wind measurements, wind profiles (if available), atmospheric stability profiles, mixing heights.
Receptor data requirements are: receptor coordinates.
Other data requirements: coordinates of the computational domain, grid cell specification, terrain elevations, user's computational and printing options.
The model's output is provided according to user's printing flags. Hourly, 3-hour and 24-hour concentration averages are computed, together with highest and highest-second-highest concentration values. Both partial and total concentrations are provided.
AVACTA II is Gaussian segment/puff model.
AVACTA II can handle any couple of primary-secondary pollutants (e.g., SO
The AVACTA II approach maintains the basic Gaussian formulation, but allows a numerical simulation of both nonstationary and nonhomogeneous meteorological conditions. The emitted pollutant material is divided into a sequence of “elements,” either segments or puffs, which are connected together but whose dynamics are a function of the local meteorological conditions. Since the meteorological parameters vary with time and space, each element evolves according to the different meteorological conditions encountered along its trajectory.
AVACTA II calculates the partial contribution of each source in each receptor during each interval. The partial concentration is the sum of the contribution of all existing puffs, plus that of the closest segment.
The user can select the following plume rise formulas:
Briggs (1969, 1971, 1972)
CONCAWE (Briggs, 1975)
Lucas-Moore (Briggs, 1975)
User's function, i.e., a subroutine supplied by the user
With cold plumes, the program uses a special routine for the computation of the jet plume rise. The user can also select several computational options that control plume behavior in complex terrain and its total/partial reflections.
A 3D mass-consistent wind field is optionally generated.
A 3D mass-consistent wind field is optionally generated.
During each step, the sigmas of each element are increased. The user can select the following sigma functions:
Pasquill-Gifford-Turner (in the functional form specified by Green et al., 1980)
Brookhaven (Gifford, 1975)
Briggs, open country (Gifford, 1975)
Briggs, urban, i.e., McElroy-Pooler (Gifford, 1975)
Irwin (1979a)
LO-LOCAT (MacCready et al., 1974)
User-specified function, by points
User-specified function, with a user's subroutine
The virtual distance/age concept is used for incrementing the sigmas at each time step.
During each step, the sigmas of each element are increased. The user can select the following sigma functions:
Pasquill-Gifford-Turner (in the functional form specified by Green et al., 1980)
Brookhaven (Gifford, 1975)
Briggs, open country (Gifford, 1975)
Briggs, urban, i.e., McElroy-Pooler (Gifford, 1975)
LO-LOCAT (MacCready et al., 1974)
User-specified function, with a user's subroutine
The virtual distance/age concept is used for incrementing the sigmas at each time step.
First order chemical reactions (primary-to-secondary pollutant)
First order dry and wet deposition schemes
Zannetti P., G. Carboni and A. Ceriani, 1985. AVACTA II Model Simulations of Worst-Case Air Pollution Scenarios in
Environmental Protection Agency, 1989. User's Guide for the DEGADIS 2.1—Dense Gas Dispersion Model. EPA Publication No. EPA-450/4-89-019. U.S. Environmental Protection Agency, Research Triangle Park, NC 27711. (NTIS No. PB 90-213893)
The model code is only available on the Support Center for Regulatory Air Models Bulletin Board System (see section B.0).
DEGADIS 2.1 is a mathematical dispersion model that can be used to model the transport of toxic chemical releases into the atmosphere. Its range of applicability includes continuous, instantaneous, finite duration, and time-variant releases; negatively-buoyant and neutrally-buoyant releases; ground-level, low-momentum area releases; ground-level or elevated upwardly-directed stack releases of gases or aerosols. The model simulates only one set of meteorological conditions, and therefore should not be considered applicable over time periods much longer than 1 or 2 hours. The simulations are carried out over flat, level, unobstructed terrain for which the characteristic surface roughness is not a significant fraction of the depth of the dispersion layer. The model does not characterize the density of aerosol-type releases; rather, the user must assess that independently prior to the simulation.
DEGADIS can be used as a refined modeling approach to estimate short-term ambient concentrations (1-hour or less averaging times) and the expected area of exposure to concentrations above specified threshold values for toxic chemical releases. The model is especially useful in situations where density effects are suspected to be important and where screening estimates of ambient concentrations are above levels of concern.
Data may be input directly from an external input file or via keyboard using an interactive program module. The model is not set up to accept real-time meteorological data or convert units of input values. Chemical property data must be input by the user. Such data for a few selected species are available within the model. Additional data may be added to this data base by the user.
Source data requirements are: emission rate and release duration; emission chemical and physical properties (molecular weight, density vs. concentration profile in the case of aerosol releases, and contaminant heat capacity in the case of a nonisothermal gas release; stack parameters (i.e., diameter, elevation above ground level, temperature at release point).
Meteorological data requirements are: wind speed at designated height above ground, ambient temperature and pressure, surface roughness, relative humidity, and ground surface temperature (which in most cases can be adequately approximated by the ambient temperature).
Receptor data requirements are: averaging time of interest, above-ground height of receptors, and maximum distance between receptors (since the model computes downwind receptor distances to optimize model performance, this parameter is used only for nominal control of the output listing, and is of secondary importance). No indoor concentrations are calculated by the model.
Printed output includes in tabular form:
• Listing of model input data;
• Plume centerline elevation, mole fraction, concentration, density, and temperature at each downwind distance;
•
• Off-centerline distances to 2 specified concentration values at a specified receptor height at each downwind distance (these values can be used to draw concentration isopleths after model execution);
• Concentration vs. time histories for finite-duration releases (if specified by user).
The output print file is automatically saved and must be sent to the appropriate printer by the user after program execution.
No graphical output is generated by the current version of this program.
DEGADIS estimates plume rise and dispersion for vertically-upward jet releases using mass and momentum balances with air entrainment based on laboratory and field-scale data. These balances assume Gaussian similarity profiles for velocity, density, and concentration within the jet. Ground-level denser-than-air phenomena is treated using a power law concentration distribution profile in the vertical and a hybrid top hat-Gaussian concentration distribution profile in the horizontal. A power law specification is used for the vertical wind profile. Ground-level cloud slumping phenomena and air entrainment are based on laboratory measurements and field-scale observations.
Neutrally- or negatively-buoyant gases and aerosols. Pollutants are assumed to be non-reactive and non-depositing.
Only one source can be modeled at a time.
There is no limitation to the number of receptors; the downwind receptor distances are internally-calculated by the model. The DEGADIS calculation is carried out until the plume centerline concentration is 50% below the lowest concentration level specified by the user.
The model contains no modules for source calculations or release characterization.
Jet/plume trajectory is estimated from mass and momentum balance equations. Surrounding terrain is assumed to be flat, and stack tip downwash, building wake effects, and fumigation are not treated.
Constant logarithmic velocity profile which accounts for stability and surface roughness is used.
The wind speed profile exponent is determined from a least squares fit of the logarithmic profile from ground level to the wind speed reference height. Calm winds can be simulated for ground-level low-momentum releases.
Along-wind dispersion of transient releases is treated using the methods of Colenbrander (1980) and Beals (1971).
Not treated.
When the plume centerline is above ground level, horizontal dispersion coefficients are based upon Turner (1969) and Slade (1968) with adjustments made for averaging time and plume density.
When the plume centerline is at ground level, horizontal dispersion also accounts for entrainment due to gravity currents as parameterized from laboratory experiments.
When the plume centerline is above ground level, vertical dispersion coefficients are based upon Turner (1969) and Slade (1968). Perfect ground reflection is applied.
In the ground-level dense-gas regime, vertical dispersion is also based upon results from laboratory experiments in density-stratified fluids.
Not specifically treated.
Not treated.
Spicer, T.O. and J.A. Havens, 1986. Development of Vapor Dispersion Models for Nonneutrally Buoyant Gas Mixtures—Analysis of USAF/N
Spicer, T.O. and J.A. Havens, 1988. Development of Vapor Dispersion Models for Nonneutrally Buoyant Gas Mixtures—Analysis of TFI/NH
The model requires either a VAX computer or an IBM
ENSR Consulting and Engineering, 1990. ERT Visibility Model: Version 4; Technical Description and User's Guide. Document M2020-003. ENSR Consulting and Engineering, 35 Nagog Park, Acton, MA 01720.
The user's guide and model code on diskette are available as a package (as PB 96-501978) from the National Technical Information Service (see section B.0).
The ERT Visibility Model is a Gaussian dispersion model designed to estimate visibility impairment for arbitrary lines of sight due to isolated point source emissions by simulating gas-to-particle conversion, dry deposition, NO to NO
There is no specific recommendation at the present time. The ERT Visibility Model may be used on a case-by-case basis.
Source data requirements are: stack height, stack temperature, emissions of SO
Meteorological data requirements are: hourly ambient temperature, mixing depth,
Receptor data requirements are: observer coordinates with respect to source, latitude, longitude, time zone, date, time of day, elevation, relative humidity, background visual range, line-of-sight azimuth and elevation angle, inclination angle of the observed object, distance from observer to object, object and surface reflectivity, number and spacing of integral receptor points along line of sight.
Other data requirements are: ambient concentrations of O
Printed output includes both summary and detailed results as follows: Summary output: Page 1—site, observer and object parameters; Page 2—optical pollutants and associated extinction coefficients; Page 3—plume model input parameters; Page 4—total calculated visual range reduction, and each pollutant's contribution; Page 5—calculated plume contrast, object contrast and object contrast degradation at the 550nm wavelength; Page 6—calculated blue/red ratio and
Detailed output: phase functions for each pollutant in four wavelengths (400, 450, 550, 650nm), concentrations for each pollutant along sight path, solar geometry contrast parameters at all wavelengths, intensities, tristimulus values and chromaticity coordinates for views of the object, sun, background sky and plume.
ERT Visibility model is a Gaussian plume model for estimating visibility impairment.
Optical activity of sulfate, nitrate (derived from SO
Single source and hour is simulated. Unlimited number of lines-of-sight (receptors) is permitted per model run.
Briggs (1971) plume rise equations for final rise are used.
A single wind speed and direction is specified for each case study. The wind is assumed to be spatially uniform.
Vertical wind speed is assumed equal to zero.
Rural dispersion coefficients from Turner (1969) are used.
Rural dispersion coefficients from Turner (1969) are used. Mixing height is accounted for with multiple reflection handled by summation of series near the source, and Fourier representation farther downwind.
First order transformations of sulfates and nitrates are used.
Dry deposition is treated by the source depletion method.
Seigneur, C., R.W. Bergstrom and A.B. Hudischewskyj, 1982. Evaluation of the EPA PLUVUE Model and the ERT Visibility Model Based on the 1979 VISTTA Data Base. EPA Publication No. EPA-450/4-82-008. U.S. Environmental Protection Agency, Research Triangle Park, NC.
White, W.H., C. Seigneur, D.W. Heinold, M.W. Eltgroth, L.W. Richards, P.T. Roberts, P.S. Bhardwaja, W.D. Conner and W.E. Wilson, Jr., 1985. Predicting the Visibility of Chimney Plumes: An Inter-comparison of Four Models with Observations at a Well-Controlled Power Plant. Atmospheric Environment, 19: 515-528.
(Dispersion Models for Ideal Gases and Hydrogen Fluoride)
Post, L. (ed.), 1994. HGSYSTEM 3.0 Technical Reference Manual. Shell Research Limited, Thornton Research Centre, Chester, United Kingdom. (TNER 94.059)
Post, L., 1994. HGSYSTEM 3.0 User's Manual. Shell Research Limited, Thornton Research Centre, Chester, United Kingdom. (TNER 94.059)
The PC-DOS version of the HGSYSTEM software (HGSYSTEM: Version 3.0, Programs for modeling the dispersion of ideal gas and hydrogen fluoride releases, executable programs and source code can be installed from diskettes. These diskettes and all documentation are available as a package from API [(202) 682-8340] or from NTIS as PB 96-501960 (see section B.0).
Doug N. Blewitt, AMOCO Corporation, 1670 Broadway/MC 2018, Denver, CO, 80201, (303) 830-5312.
Howard J. Feldman, American Petroleum Institute, 1220 L Street Northwest, Washington, DC 20005, (202) 682-8340.
HGSYSTEM is a PC-based software package consisting of mathematical models for estimating of one or more consecutive phases between spillage and near-field and far-field dispersion of a pollutant. The pollutant can be either a two-phase, multi-compound mixture of non-reactive compounds or hydrogen fluoride (HF) with chemical reactions. The individual models are:
Database program:
DATAPROP Generates physical properties used in other HGSYSTEM models
Source term models:
SPILL Transient liquid release from a pressurized vessel
HFSPILL SPILL version specifically for HF
LPOOL Evaporating multi-compound liquid pool model
Near-field dispersion models:
AEROPLUME High-momentum jet dispersion model
HFPLUME AEROPLUME version specifically for HF
HEGABOX Dispersion of instantaneous heavy gas releases
Far-field dispersion models:
HEGADAS(S,T) Heavy gas dispersion (steady-state and transient version)
PGPLUME Passive Gaussian dispersion
Utility programs:
HFFLASH Flashing of HF from pressurized vessel
POSTHS/POSTHT Post-processing of HEGADAS(S,T) results
PROFILE Post-processor for concentration contours of airborne plumes
GET2COL Utility for data retrieval
The models assume flat, unobstructed terrain. HGSYSTEM can be used to model steady-state, finite-duration, instantaneous and time dependent releases, depending on the individual model used. The models can be run consecutively, with relevant data being passed on from one model to the next using link files. The models can be run in batch mode or using an iterative utility program.
HGSYSTEM can be used as a refined model to estimate short-term ambient concentrations. For toxic chemical releases (non-reactive chemicals or hydrogen fluoride; 1-hour or less averaging times) the expected area of exposure to concentrations above specified threshold values can be determined. For flammable non-reactive gases it can be used to determine the area in which the cloud may ignite.
HFSPILL input data: reservoir data (temperature, pressure, volume, HF mass, mass-fraction water), pipe-exit diameter and ambient pressure.
EVAP input data: spill rate, liquid properties, and evaporation rate (boiling pool) or ambient data (non-boiling pool).
HFPLUME and PLUME input data: reservoir characteristics, pollutant parameters, pipe/release data, ambient conditions, surface roughness and stability class.
HEGADAS input data: ambient conditions, pollutant parameters, pool data or data at transition point, surface roughness, stability class and averaging time.
PGPLUME input data: link data provided by HFPLUME and the averaging time.
The HGSYSTEM models contain three post-processor programs which can be used to extract modeling results for graphical display by external software packages. GET2COL can be used to extract data from the model output files. HSPOST can be used to develop isopleths, extract any 2 parameters for plotting and correct for finite release duration. HTPOST can be used to produce time history plots.
HFSPILL output data: reservoir mass, spill rate, and other reservoir variables as a function of time. For HF liquid, HFSPILL generates link data to HFPLUME for the initial phase of choked liquid flow (flashing jet), and link data to EVAP for the subsequent phase of unchoked liquid flow (evaporating liquid pool).
EVAP output data: pool dimensions, pool evaporation rate, pool mass and other pool variables for steady state conditions or as a function of time. EVAP generates link data to the dispersion model HEGADAS (pool dimensions and pool evaporation rate).
HFPLUME and PLUME output data: plume variables (concentration, width, centroid height, temperature, velocity, etc.) as a function of downwind distance.
HEGADAS output data: concentration variables and temperature as a function of downwind distance and (for transient case) time.
PGPLUME output data: concentration as a function of downwind distance, cross-wind distance and height.
HGSYSTEM is made up of four types of dispersion models. HFPLUME and PLUME simulate the near-field dispersion and PGPLUME simulates the passive-gas dispersion downwind of a transition point.
HGSYSTEM may be used to model non-reactive chemicals or hydrogen fluoride.
HGSYSTEM estimates the expected area of exposure to concentrations above user-specified threshold values. By imposing conservation of mass, momentum and energy the concentration, density, speed and temperature are evaluated as a function of downwind distance.
HFPLUME and PLUME: (1) are steady-state models assuming a top-hat profile with cross-section averaged plume variables; and (2) the momentum equation is taken into account for horizontal ambient shear, gravity, ground collision, gravity-slumping pressure forces and ground-surface drag.
HEGADAS: assumes the heavy cloud to move with the ambient wind speed, and adopts a power-law fit of the ambient wind speed for the velocity profile.
PGPLUME: simulates the passive-gas dispersion downwind of a transition point from HFPLUME or PLUME for steady-state and finite duration releases.
A power law fit of the ambient wind speed is used.
Not treated.
HFPLUME and PLUME: Plume dilution is caused by air entrainment resulting from high plume speeds, trailing vortices in wake of falling plume (before touchdown), ambient turbulence and density stratification. Plume dispersion is assumed to be steady and momentum-dominated, and effects of downwind diffusion and wind meander (averaging time) are not taken into account.
HEGADAS: This model adopts a concentration similarity profile expressed in terms of an unknown center-line ground-level concentration and unknown vertical/cross-wind dispersion parameters. These quantities are determined from a number of basic equations describing gas-mass conservation, air entrainment (empirical law describing vertical top-entrainment in terms of global Richardson number), cross-wind gravity spreading (initial gravity spreading followed by gravity-current collapse) and cross-wind diffusion (Briggs formula).
PGPLUME: This model assumes a Gaussian concentration profile in which the cross-wind and vertical dispersion coefficients are determined by empirical expressions. All unknown parameters in this profile are determined by imposing appropriate matching criteria at the transition point.
See description above.
Not treated.
Not treated.
PLUME has been validated against field data for releases of liquified propane, and wind tunnel data for buoyant and vertically-released dense plumes. HFPLUME and PLUME have been validated against field data for releases of HF (Goldfish experiments) and propane releases. In addition, the plume rise algorithms have been tested against Hoot, Meroney, and Peterka, Ooms and Petersen databases. HEGADAS has been validated against steady and transient releases of liquid propane and LNG over water (Maplin Sands field data), steady and finite-duration pressurized releases of HF (Goldfish experiments; linked with HFPLUME), instantaneous release of Freon (Thorney Island field data; linked with the box model HEGABOX) and wind tunnel data for steady, isothermal dispersion.
Validation studies are contained in the following references.
McFarlane, K., Prothero, A., Puttock, J.S., Roberts, P.T. and H.W.M. Witlox, 1990. Development and validation of atmospheric dispersion models for ideal gases and hydrogen fluoride, Part I: Technical Reference Manual. Report TNER.90.015. Thornton Research Centre, Shell Research, Chester, England. [EGG 1067-1151] (NTIS No. DE 93-000953)
Witlox, H.W.M., McFarlane, K., Rees, F.J. and J.S. Puttock, 1990. Development and validation of atmospheric dispersion models for ideal gases and hydrogen fluoride, Part II: HGSYSTEM Program User's Manual. Report TNER.90.016. Thornton Research Centre, Shell Research, Chester, England. [EGG 1067-1152] (NTIS No. DE 93-000954)
Mellor, G.L. and T. Yamada, 1974. A Hierarchy of Turbulence Closure Models for Planetary Boundary Layers. Journal of Atmospheric Sciences, 31: 1791-1806.
Mellor, G.L. and T. Yamada, 1982. Development of a Turbulence Closure Model for Geophysical Fluid Problems. Rev. Geophys. Space Phys., 20: 851-875.
Yamada, T. and S. Bunker, 1988. Development of a Nested Grid, Second Moment Turbulence Closure Model and Application to the 1982 ASCOT Brush Creek Data Simulation. Journal of Applied Meteorology, 27: 562-578.
For a cost to be negotiated with the model developer, a
YSA Corporation offers a comprehensive modeling system for environmental studies. The system includes a mesoscale meteorological code, a transport and diffusion code, and extensive Graphical User Interfaces (GUIs). This system is unique because the diffusion code uses time dependent, three-dimensional winds and turbulence distributions that are forecasted by a mesoscale weather prediction model. Consequently the predicted concentration distributions are more accurate than those predicted by traditional models when surface conditions are heterogeneous. In general, the modeled concentration distributions are not Gaussian because winds and turbulence distributions The models were originally developed by using super computers. However, recent advancement of computer hardware has made it possible to run complex three-dimensional meteorological models on desktop workstations. The present versions of the programs are running on super computers and workstations. GUIs are available on Sun Microsystems and Silicon Graphics workstations. The modeling system can also run on a laptop workstation which makes it possible to run the programs in the field or away from the office. As technology continues to advance, a version of HOTMAC/RAPTAD suitable for PC-based platforms will be considered for release by YSA.
HOTMAC, Higher Order Turbulence Model for Atmospheric Circulation, is a mesoscale weather prediction model that forecasts wind, temperature, humidity, and atmospheric turbulence distributions over complex surface conditions. HOTMAC has options to include non-hydrostatic pressure computation, nested grids, land-use distributions, cloud, fog, and precipitation physics. HOTMAC can interface with tower, rawinsonde, and large-scale weather data using a four-dimensional data assimilation method. RAPTAD, Random Puff Transport and Diffusion, is a Lagrangian random puff model that is used to forecast transport and diffusion of airborne materials over complex terrain. Concentrations are computed by summing the concentration of each puff at the receptor location. The random puff method is equivalent to the random particle method with a Gaussian kernel for particle distribution. The advantage of the puff method is the accuracy and speed of computation. The particle method requires the release of a large number of particles which could be computationally expensive. The puff method requires the release of a much less number of puffs, typically
The averaging time for concentration estimates is variable from 5 minutes to 15 minutes for each receptor. In addition to the concentration computation at the receptor sites, RAPTAD computes and graphically displays hourly concentration contours at the ground level. RAPTAD is applicable to point and area sources.
The meteorological data produced from HOTMAC are used as input to RAPTAD. RAPTAD can forecast concentration distributions for neutrally buoyant gas, buoyant gas and denser-than-air gas. The models are significantly advanced in both their model physics and in their operational procedures. GUIs are provided to help the user prepare input files, run programs, and display the modeled results graphically in three dimensions.
There are no specific recommendations at the present time. The HOTMAC/RAPTAD modeling system may be used on a case-by-case basis.
Meteorological Data: The modeling system is significantly different from the majority of regulatory models in terms of how meteorological data are provided and used in concentration simulations. Regulatory models use the wind data which are obtained directly from measurements or analyzed by using a simple constraint such as a mass conservation equation. Thus, the accuracy of the computation will depend significantly on the quantity and quality of the wind data. This approach is acceptable as long as the study area is flat and the simulation period is short. As the regulations become more stringent and more realistic surface conditions are required, a significantly large volume of meteorological data is required which could become very expensive.
An alternative approach is to augment the measurements with predicted values from a mesoscale meteorological model. This is the approach we have taken here. This approach
HOTMAC requires meteorological data for initialization and to provide boundary conditions if the boundary conditions change significantly with time. The minimum amount of data required to run HOTMAC is wind and potential temperature profiles at a single station. HOTMAC forecasts wind and turbulence distributions in the boundary layer through a set of model equations for solar radiation, heat energy balance at the ground, conservation of momentum, conservation of internal energy, and conservation of mass.
Terrain Data: HOTMAC and RAPTAD use the digitized terrain data from the U.S. Geological Survey and the Defense Mapping Agency. Extraction of terrain data is greatly simplified by using YSA's GUI software called Topo. The user specifies the latitudes and longitudes of the southwest and northeast corner points of the study area. Then, Topo extracts the digitized elevation data within the area specified and converts from the latitudes and longitudes to the UTM (Universal Transverse Mercator) coordinates for up to three nested grids.
Emission Data: Emission data requirements are emission rate, stack height, stack diameter, stack location, stack gas exit velocity, and stack buoyancy.
Receptor Data: Receptor data requirements are names, location coordinates, and desired averaging time for concentration estimates, which is variable from 5 to 15 minutes.
HOTMAC outputs include hourly winds, temperatures, and turbulence variables at every grid point. Ancillary codes graphically display vertical profiles of wind, temperature, and turbulence variables at selected locations and wind vector distributions at specified heights above the ground. These codes also produce graphic files of wind direction projected on vertical cross sections.
RAPTAD outputs include hourly values of surface concentration, time variations of mean and standard deviation of concentrations at selected locations, and coordinates of puff center locations. Ancillary codes produce color contour plots of surface concentration, time variations of mean concentrations and ratios of standard deviation to mean value at selected locations, and concentration distributions in the vertical cross sections. The averaging time of concentration at a receptor location is variable from 5 to 15 minutes. Color contour plots of surface concentration can be animated on the monitor to review time variations of high concentration areas.
HOTMAC is a 3-dimensional Eulerian model for weather forecasting, and RAPTAD is a 3-dimensional Lagrangian random puff model for pollutant transport and diffusion.
RAPTAD may be used to model any inert pollutants, including dense and buoyant gases.
Up to six point or area sources are specified and up to 50 sampling locations are selected. Source and receptor heights are specified by the user.
Neutrally buoyant plumes are transported by mean and turbulence winds that are modeled by HOTMAC. Non-neutrally buoyant plume equations are based on Van Dop (1992). In general, plumes are non-Gaussian.
RAPTAD uses wind speed, wind direction, and turbulence on a gridded array that is supplied hourly by HOTMAC. Stability effect and mixed layer height are incorporated through the intensity of turbulence which is a function of stability. HOTMAC predicts turbulence intensity by solving a turbulence kinetic energy equation and a length scale equation. RAPTAD interpolates winds and turbulence at puff center locations every 10 seconds from the values on a gridded array. RAPTAD can also use the winds observed at towers and by rawinsondes.
RAPTAD uses vertical winds on a gridded array that are supplied hourly by HOTMAC. HOTMAC computes vertical wind either by solving an equation of motion for the vertical wind or a mass conservation equation. RAPTAD interpolates vertical winds at puff center locations every 10 seconds from the values on a gridded array.
Horizontal dispersion is based on the standard deviations of horizontal winds that are computed by HOTMAC.
Vertical dispersion is based on the standard deviations of vertical wind that are computed by HOTMAC.
HOTMAC can provide meteorological inputs to other models that handle chemical reactions, e.g., UAM.
Not treated.
Yamada, T., S. Bunker and M. Moss, 1992. A Numerical Simulation of Atmospheric Transport and Diffusion over Coastal Complex Terrain. Journal of Applied Meteorology, 31: 565-578.
Yamada, T. and T. Henmi, 1994. HOTMAC: Model Performance Evaluation by Using Project WIND Phase I and II Data. Mesoscale Modeling of the Atmosphere, American Meteorological Society, Monograph 47, pp. 123-135.
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs, Volumes I and II, EPA Publication No. EPA-903/9-82-004. U.S. Environmental Protection Agency, Region III, Philadelphia, PA.
The computer code is available on the Support Center for Regulatory Air Models Bulletin Board System and on diskette (as PB 96-501994) from the National Technical Information Service (see section B.0).
LONGZ utilizes the steady-state univariate Gaussian plume formulation for both urban and rural areas in flat or complex terrain to calculate long-term (seasonal and/or annual) ground-level ambient air concentrations attributable to emissions from up to 14,000 arbitrarily placed sources (stacks, buildings and area sources). The output consists of the total concentration at each receptor due to emissions from each user-specified source or group of sources, including all sources. An option which considers losses due to deposition (see the description of SHORTZ) is deemed inappropriate by the authors for complex terrain, and is not discussed here.
LONGZ can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. LONGZ must be executed in the equivalent mode.
LONGZ can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section 3.2 of appendix W, that LONGZ is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data requirements are: for point, building or area sources, location, elevation, total emission rate (optionally classified by gravitational settling velocity) and decay coefficient; for stack sources, stack height, effluent temperature, effluent exit velocity, stack radius (inner), emission rate, and ground elevation (optional); for building sources, height, length and width, and orientation; for area sources, characteristic vertical dimension, and length, width and orientation.
Meteorological data requirements are: wind speed and measurement height, wind profile exponents, wind direction standard deviations (turbulent intensities), mixing height, air temperature, vertical potential temperature gradient.
Receptor data requirements are: coordinates, ground elevation.
Printed output includes total concentration due to emissions from user-specified source groups, including the combined emissions from all sources (with optional allowance for depletion by deposition).
LONGZ is a climatological Gaussian plume model.
LONGZ may be used to model primary pollutants. Settling and deposition are treated.
LONGZ applies user specified locations for sources and receptors. Receptors are assumed to be at ground level.
Plume rise equations of Bjorklund and Bowers (1982) are used.
Stack tip downwash (Bjorklund and Bowers, 1982) is included.
All plumes move horizontally and will fully intercept elevated terrain.
Plumes above mixing height are ignored.
Perfect reflection at mixing height is assumed for plumes below the mixing height.
Plume rise is limited when the mean wind at stack height approaches or exceeds stack exit velocity.
Perfect reflection at ground is assumed for pollutants with no settling velocity.
Zero reflection at ground is assumed for pollutants with finite settling velocity.
LONGZ does not simulate fumigation.
Tilted plume is used for pollutants with settling velocity specified.
Buoyancy-induced dispersion is treated (Briggs, 1972).
Wind field is homogeneous and steady-state.
Wind speed profile exponents are functions of both stability class and wind speed. Default values are specified in Bjorklund and Bowers (1982).
Vertical wind speed is assumed equal to zero.
Pollutants are initially uniformly distributed within each wind direction sector. A smoothing function is then used to remove discontinuities at sector boundaries.
Vertical dispersion is derived from input vertical turbulent intensities using adjustments to plume height and rate of plume growth with downwind distance specified in Bjorklund and Bowers (1982).
Chemical transformations are treated using exponential decay. Time constant is input by the user.
Gravitational settling and dry deposition of particulates are treated.
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs, Volume I and II. EPA Publication No. EPA-903/9-82-004. U.S. Environmental Protection Agency, Region III, Philadelphia, PA.
Brower, R., 1982. The Maryland Power Plant Siting Program (PPSP) Air Quality Model User's Guide. Ref. No. PPSP-MP-38. Prepared for Maryland Department of Natural Resources by Environmental Center, Martin Marietta Corporation, Baltimore, MD. (NTIS No. PB 82-238387)
Weil, J.C. and R.P. Brower, 1982. The Maryland PPSP Dispersion Model for Tall Stacks. Ref. No. PPSP-MP-36. Prepared for Maryland Department of Natural Resources by Environmental Center, Martin Marietta Corporation, Baltimore, MD. (NTIS No. PB 82-219155)
The model code and test data are available on diskette for a nominal cost to defray shipping and handling charges from: Mr. Roger Brower, Versar, Inc., 9200 Rumsey Road, Columbia, MD 21045; Phone: (410) 964-9299.
PPSP is a Gaussian dispersion model applicable to tall stacks in either rural or urban areas, but in terrain that is essentially flat (on a scale large compared to the ground roughness elements). The PPSP model follows the same general formulation and computer coding as CRSTER, also a Gaussian model, but it differs in four major ways. The differences are in the scientific formulation of specific ingredients or “sub-models” to the Gaussian model, and are based on recent theoretical improvements as well as supporting experimental data. The differences are: (1) stability during daytime is based on convective scaling instead of the Turner criteria; (2) Briggs' dispersion curves for elevated sources are used; (3) Briggs plume rise formulas for convective conditions are included; and (4) plume penetration of elevated stable layers is given by Briggs' (1984) model.
PPSP can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. PPSP must be executed in the equivalent mode.
PPSP can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section 3.2 of appendix W, that PPSP is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data requirements are: emission rate (monthly rates optional), physical stack height, stack gas exit velocity, stack inside diameter, stack gas temperature.
Meteorological data requirements are: hourly surface weather data from the EPA meteorological preprocessor program.
Receptor data requirements are: distance of each of the five receptor rings.
Printed output includes:
Highest and second highest concentrations for the year at each receptor for averaging times of 1, 3, and 24-hours, plus a user-selected averaging time which may be 2, 4, 6, 8, or 12 hours;
Annual arithmetic average at each receptor; and
For each day, the highest 1-hour and 24-hour concentrations over the receptor field.
PPSP is a Gaussian plume model.
PPSP may be used to model primary pollutants. Settling and deposition are not treated.
Up to 19 point sources are treated.
All point sources are assumed at the same location.
Unique stack height and stack exit conditions are applied for each source.
Receptor locations are restricted to 36 azimuths (every 10 degrees) and five user-specified radial distances.
Briggs (1975) final rise formulas for buoyant plumes are used. Momentum rise is not considered.
Transitional or distance-dependent plume rise is not modeled.
Penetration (complete, partial, or zero) of elevated inversions is treated with Briggs (1984) model; ground-level concentrations are dependent on degree of plume penetration.
Wind speeds are corrected for release height based on power law variation, with different exponents for different stability classes and variable reference height (7 meters is default). Wind speed power law exponents are 0.10, 0.15, 0.20, 0.25, 0.30, and 0.30 for stability classes A through F, respectively.
Constant, uniform (steady-state) wind assumed within each hour.
Vertical wind speed is assumed equal to zero.
Rural dispersion parameters are Briggs (Gifford, 1975), with stability class defined by u/w* during daytime, and by the method of Turner (1964) at night.
Urban dispersion is treated by changing all stable cases to stability class D.
Buoyancy-induced dispersion (Pasquill, 1976) is included (using
Rural dispersion parameters are Briggs (Gifford, 1975), with stability class defined by u/w* during daytime, and by the method of Turner (1964).
Urban dispersion is treated by changing all stable cases to stability class D.
Buoyancy-induced dispersion (Pasquill, 1976) is included (using
Not treated.
Not treated.
Londergan, R., D. Minott, D. Wackter, T. Kincaid and D. Bonitata, 1983. Evaluation of Rural Air Quality Simulation Models, Appendix G: Statistical Tables for PPSP. EPA Publication No. EPA-450/4-83-003. Environmental Protection Agency, Research Triangle Park, NC.
Weil, J.C. and R.P. Brower, 1982. The Maryland PPSP dispersion model for tall stacks. Ref. No. PPSP MP-36. Prepared for Maryland Department of Natural Resources. Prepared by Environmental Center, Martin Marietta Corporation, Baltimore, Maryland. (NTIS No. PB 82-219155)
Scire, J.S., F.W. Lurmann, A. Bass and S.R. Hanna, 1984. User's Guide to the Mesopuff II Model and Related Processor Programs. EPA Publication No. EPA-600/8-84-013. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 84-181775)
A Modeling Protocol for Applying MESOPUFF II to Long Range Transport Problems, 1992. EPA Publication No. EPA-454/R-92-021. U.S. Environmental Protection Agency, Research Triangle Park, NC.
This model code is available on the Support Center for Regulatory Air Models Bulletin Board System and also on diskette (as PB 93-500247) from the National Technical Information Service (see section B.0).
MESOPUFF II is a short term, regional scale puff model designed to calculate concentrations of up to 5 pollutant species (SO
There is no specific recommendation at the present time. The model may be used on a case-by-case basis.
Required input data include four types: (1) input control parameters and selected technical options, (2) hourly surface meteorological data and twice daily upper air measurements, hourly precipitation data are optional, (3) surface land use classification information, (4) source and emissions data.
Data from up to 25 surface National Weather Service stations and up to 10 upper air stations may be considered. Spatially variable fields at hour intervals of winds, mixing height, stability class, and relevant turbulence parameters are derived by MESOPAC II, the meteorological preprocessor program described in the User Guide.
Source and emission data for up to 25 point sources and/or up to 5 area sources can be included. Required information are: location in grid coordinates, stack height, exit velocity and temperature, and emission rates for the pollutant to be modeled.
Receptor data requirements: up to a 40×40 grid may be used and non-gridded receptor locations may be considered.
Line printer output includes: all input parameters, optionally selected arrays of ground-level concentrations of pollutant species at specified time intervals.
Line printer contour plots output from MESOFILE II post-processor program. Computer readable output of concentration array to disk/tape for each hour.
MESOPUFF II is a Gaussian puff superposition model.
Up to five pollutant species may be modeled simultaneously and include: SO
Up to 25 point sources and/or up to 5 area sources are permitted.
Briggs (1975) plume rise equations are used, including plume penetration with buoyancy flux computed in the model.
Fumigation of puffs is considered and may produce immediate mixing or multiple reflection calculations at user option.
Gridded wind fields are computed for 2 layers; boundary layer and above the mixed layer. Upper air rawinsonde data and hourly surface winds are used to obtain spatially variable u,v component fields at hourly intervals. The gridded fields are computed by interpolation between stations in the MESOPAC II preprocessor.
Vertical winds are assumed to be zero.
Incremental puff growth is computed over discrete time steps with horizontal growth parameters determined from power law equations fit to sigma y curves of Turner out to 100km. At distances greater than 100km, puff growth is determined by the rate given by Heffter (1965).
Puff growth is a function of stability class and changes in stability are treated. Optionally, user input plume growth coefficients may be considered.
For puffs emitted at an effective stack height which is less than the mixing height, uniform mixing of the pollutant within the mixed layer is performed. For puffs centered above the mixing height, no effect at the ground occurs.
Hourly chemical rate constants are computed from empirical expressions derived from photochemical model simulations.
Dry deposition is treated with a resistance method.
Wet removal may be considered if hourly precipitation data are input.
Results of tests for some model parameters are discussed in:
Scire, J.S., F.W. Lurmann, A. Bass and S.R. Hanna, 1984. Development of the MESOPUFF II Dispersion Model. EPA Publication No. EPA-600/3-84-057. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Wang, I.T. and T.L. Waldron, 1980. User's Guide for MTDDIS Mesoscale Transport, Diffusion, and Deposition Model for Industrial Sources. EMSC6062.1UR(R2). Combustion Engineering, Newbury Park, CA.
A diskette copy of the FORTRAN coding and the user's guide are available for a cost of $100 from: Dr. I. T. Wang, Environmental Modeling & Analysis, 2219 E. Thousand Oaks Blvd., Suite 435, Thousand Oaks, CA 91362.
MTDDIS is a variable-trajectory Gaussian puff model applicable to long-range transport of point source emissions over level or rolling terrain. The model can be used to determine 3-hour maximum and 24-hour average concentrations of relatively nonreactive pollutants from up to 10 separate stacks.
There is no specific recommendation at the present time. The MTDDIS Model may be used on a case-by-case basis.
Source data requirements are: emission rate, physical stack height, stack gas exit velocity, stack inside diameter, stack gas temperature, and location.
Meteorological data requirements are: hourly surface weather data, from up to 10 stations, including cloud ceiling, wind direction, wind speed, temperature, opaque cloud cover and precipitation. For long-range applications, user-analyzed daily mixing heights are recommended. If these are not available, the NWS daily mixing heights will be used by the program. A single upper air sounding station for the region is assumed. For each model run, air trajectories are generated for a 48-hour period, and therefore, the afternoon mixing height of the day before and the mixing heights of the day after are also required by the model as input, in order to generate hourly mixing heights for the modeled period.
Receptor data requirements are: up to three user-specified rectangular grids.
Printed output includes:
Tabulations of hourly meteorological parameters include both input surface observations and calculated hourly stability classes and mixing heights for each station;
Printed air trajectories for the two consecutive 24-hour periods for air parcels generated 4 hours apart starting at 0000 LST; and
3-hour maximum and 24-hour average grid concentrations over user-specified rectangular grids are output for the second 24-hour period.
MTDDIS is a Gaussian puff model.
MTDDIS can be used to model primary pollutants. Dry deposition is treated. Exponential decay can account for some reactions.
MTDDIS treats up to 10 point sources.
Up to three rectangular receptor grids may be specified by the user.
Briggs (1971, 1972) plume rise formulas are used.
If plume height exceeds mixing height, ground level concentration is assumed zero.
Fumigation and downwash are not treated.
Wind speeds and wind directions at each station are first corrected for release height. Speed conversions are based on power law variation and direction conversions are based on linear height dependence as recommended by Irwin (1979b).
Converted wind speeds and wind directions are then weighted according to the algorithms of Heffter (1980) to calculate the effective transport wind speed and direction.
Vertical wind speed is assumed equal to zero.
Transport-time-dependent dispersion coefficients from Heffter (1980) are used.
Transport-time-dependent dispersion coefficients from Heffter (1980) are used.
Chemical transformations are treated using exponential decay. Half-life is input by the user.
Dry deposition is treated. User input deposition velocity is required.
Wet deposition is treated. User input hourly precipitation rate and precipitation layer depth or cloud ceiling height are required.
Carhart, R.A., A.J. Policastro, M. Wastag and L. Coke, 1989. Evaluation of Eight Short-Term Long-Range Transport Models Using Field Data. Atmospheric Environment, 23: 85-105.
Malik, M.H. and B. Baldwin, 1980. Program Documentation for Multi-Source (SCSTER) Model. Program Documentation EN7408SS. Southern Company Services, Inc., Technical Engineering Systems, 64 Perimeter Center East, Atlanta, GA.
The SCSTER model and user's manual are available at no charge on a limited basis through Southern Company Services. The computer code may be provided on a diskette. Requests should be directed to: Mr. Stanley S. Vasa, Senior Environmental Specialist, Southern Company Services, P.O. Box 2625, Birmingham, AL 35202.
SCSTER is a modified version of the EPA CRSTER model. The primary distinctions of SCSTER are its capability to consider multiple sources that are not necessarily collocated, its enhanced receptor specifications, its variable plume height terrain adjustment procedures and plume distortion from directional wind shear.
SCSTER can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. SCSTER must be executed in the equivalent mode.
SCSTER can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section 3.2 of appendix W, that SCSTER is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data requirements are: emission rate, stack gas exit velocity, stack gas temperature, stack exit diameter, physical stack height, elevation of stack base, and coordinates of stack location. The variable emission data can be monthly or annual averages.
Meteorological data requirements are: hourly surface weather data from the EPA meteorological preprocessor program. Preprocessor output includes hourly stability class wind direction, wind speed, temperature, and mixing height. Actual anemometer height (a single value) is optional. Wind speed profile exponents (one for each stability class) are optional.
Receptor data requirements are: cartesian coordinates and elevations of individual receptors; distances of receptor rings, with elevation of each receptor; receptor grid networks, with elevation of each receptor.
Any combination of the three receptor input types may be used to consider up to 600 receptor locations.
Printed output includes:
Highest and second highest concentrations for the year at each receptor for averaging times of 1-, 3-, and 24-hours, a user-selected averaging time which may be 2-12 hours, and a 50 high table for 1-, 3-, and 24-hours;
Annual arithmetic average at each receptor; and the highest 1-hour and 24-hour concentrations over the receptor field for each day considered.
Optional tables of source contributions of individual point sources at up to 20 receptor locations for each averaging period;
Optional magnetic tape output in either binary or fixed block format includes:
All 1-hour concentrations.
Optional card/disk output includes for each receptor:
Receptor coordinates; receptor elevation; highest and highest, second-highest, 1-, 3-, and 24-hour concentrations; and annual average concentration.
SCSTER is a Gaussian plume model.
SCSTER may be used to model primary pollutants. Settling and deposition are not treated.
SCSTER can handle up to 60 separate stacks at varying locations and up to 600 receptors, including up to 15 receptor rings.
User input topographic elevation for each receptor is used.
SCSTER uses Briggs (1969, 1971, 1972) final plume rise formulas.
Transitional plume rise is optional.
SCSTER contains options to incorporate wind directional shear with a plume distortion method described in appendix A of the User's Guide.
SCSTER provides four terrain adjustments including the CRSTER full terrain height adjustment and a user-input, stability-dependent plume path coefficient adjustment for receptors above stack height.
Wind speeds are corrected for release height based on power law exponents from DeMarrais (1959), different exponents for different stability classes; default reference height of 7m. Default exponents are 0.10, 0.15, 0.20, 0.25, 0.30, and 0.30 for stability classes A through F, respectively.
Steady-state wind is assumed within a given hour.
Optional consideration of plume distortion due to user-input, stability-dependent wind-direction shear gradients.
Vertical wind speed is assumed equal to zero.
Rural dispersion coefficients from Turner (1969) are used.
Six stability classes are used.
Rural dispersion coefficients from Turner (1969) are used.
Six stability classes are used.
An optional test for plume height above mixing height before terrain adjustment is included.
Chemical transformations are treated using exponential decay. Half-life is input by the user.
Physical removal is treated using exponential decay. Half-life is input by the user.
Londergan, R., D. Minott, D. Wackter, T. Kincaid and D. Bonitata, 1983. Evaluation of Rural Air Quality Simulation Models. EPA Publication No. EPA-450/4-83-003. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Transoft Group, 1994. User's Guide of Fluidyn-PANACHE, a Three-Dimensional Deterministic Simulation of Pollutants Dispersion Model for Complex Terrain; Cary, North Carolina.
For a cost to be negotiated with the model developer, the computer code is available from: Transoft US, Inc., 818 Reedy Creek Road, Cary, NC 27513-3307; Phone: (919) 380-7500, Fax: (919) 380-7592.
PANACHE is an Eulerian (and Lagrangian for particulate matter), 3-dimensional finite volume fluid mechanics code designed to simulate continuous and short-term pollution dispersion in the atmosphere, in simple or complex terrain. For single or multiple sources, pollutant emissions from stack, point, area, volume, general sources and distant sources are treated. The model automatically treats obstacles, effects of vegetation and water bodies, the effects of vertical temperature stratification on the wind and diffusion fields, and turbulent shear flows caused by atmospheric boundary layer or terrain effects. The code solves Navier Stokes equations in a curvilinear mesh espousing the terrain and obstacles. A 2nd order resolution helps keep the number of cells limited in case of shearing flow. An initial wind field is computed by using a Lagrangian multiplier to interpolate wind data collected on site. The mesh generator, the solver and the numerical schemes have been adopted for atmospheric flows with or without chemical reactions. The model code operates on any workstation or IBM—compatible PC (486 or higher). Gaussian and puff modes are available in PANACHE for fast, preliminary simulation.
On a case-by-case basis, PANACHE may be appropriate for the following types of situations: industrial or urban zone on a flat or complex terrain, transport distance from a few meters to 50km, continuous releases with hourly, monthly or annual averaging times, chemically reactive or non-reactive gases or particulate emissions for stationary or roadway sources.
Data may be input directly from an external source (e.g., GIS file) or interactively. The model provides the option to use default values when input parameters are unavailable.
PANACHE user environment integrates the pre- and post-processor with the solver. The calculations can be done interactively or in batch mode. An inverse scheme is provided to estimate missing data from a few measured values of the wind.
Terrain data requirements:
• Location, surface roughness estimates, and altitude contours.
• Location and dimensions of obstacles, forests, fields, and water bodies.
Source data requirements:
For all types of sources, the exit temperature and plume mass flow rates and concentration of each of the pollutants are required. External sources require mass flow rate. For roadways, estimated traffic volume and vehicular emissions are required.
Meteorological data requirements:
Hourly stability class, wind direction, wind speed, temperature, cloud cover, humidity, and mixing height data with lapse rate below and above it.
Primary meteorological variables available from the National Weather Service can be processed using PCRAMMET (see section 9.3.3.2 of appendix W) to an input file.
Data required at the domain boundary:
Wind profile (uniform, log or power law), depending on the terrain conditions (e.g., residential area, forest, sea, etc.).
Chemical source data requirements:
A database of selected species with specific heats and molecular weights can be extended by the user. For heavy gases the database includes a compressibility coefficients table.
Solar reflection:
For natural convection simulation with low wind on a sunny day, approximate values of temperature for fields, forests, water bodies, shadows and their variations with the time of the day are determined automatically.
Printed output option: pollutant concentration at receptor points, and listing of input data (terrain, chemical, weather, and source data) with turbulence and precision control data.
Graphical output includes: In 3-dimensional perspective or in any crosswind, downwind or horizontal plane: wind velocity, pollutant concentration, 3-dimensional isosurface. The profile of concentration can be obtained along any line on the terrain. The concentration contours can be either instantaneous or time integrated for the emission from a source or a source combination. A special utility is included to help prepare a report or a video animation. The user can select images, put in annotations, or do animation.
The model uses an Eulerian (and Lagrangian for particulate matter) 3-dimensional finite volume model solving full Navier-Stokes equations. The numerical diffusion is low with appropriate turbulence models for building wakes. A second order resolution may be sought to limit the diffusion. Gaussian and puff modes are available. The numerical scheme is self adaptive for the following situations:
• A curvilinear mesh or a chopped Cartesian mesh is generated automatically or manually;
• Thermal and gravity effects are simulated by full gravity (heavy gases), no gravity (well mixed light gases at ambient temperature), and Boussinesq approximation methods;
• K-diff, K-e or a boundary layer turbulence models are used for turbulence calculations. The flow behind obstacles such as buildings, is calculated by using a modified K-e.
• For heavy gases, a 3-dimensional heat conduction from the ground and a stratification model for heat exchange from the atmosphere are used (with anisotropic turbulence).
• If local wind data are available, an initial wind field with terrain effects can be computed using a Lagrangian multiplier, which substantially reduces computation time.
• Scavenging, Acid Rain: A module for water droplets traveling through a plume considers the absorption and de-absorption effects of the pollutants by the droplet. Evaporation and chemical reactions with gases are also taken into account.
• Visibility: Predicts plume visibility and surface deposition of aerosol.
• Particulate matter: Calculates settling and dry deposition of particles based on a Probability Density Function (PDF) of their diameters. The exchange of mass, momentum and heat between particles and gas is treated with implicit coupling procedures.
• Ozone formation and dispersion: The photochemical model computes ozone formation and dispersion at street level in the presence of sunlight.
• Roadway Pollutants: Accounts for heat and turbulence due to vehicular movement. Emissions are based on traffic volume and emission factors.
• Odor Dispersion: Identifies odor sources for waste water plants.
• Radon Dispersion: Simulates natural radon accumulation in valleys and mine environments.
PANACHE may also be used in emergency planning and management for episodic emissions, and fire and soot spread in forested and urban areas or from combustible pools.
Simultaneous use of multiple kinds of sources at user defined locations. Any number of user defined receptors can identify pollutants from each source individually.
The options influencing the behavior are full gravity, Boussinesq approximation or no gravity.
Horizontal wind speed approximations are made only at the boundaries based on National Weather Service data. Inside the domain of interest, full Navier-Stokes resolution with natural viscosity is used for 3-dimensional terrain and temperature dependent wind field calculation.
Vertical wind speed approximations are made only at the boundaries based on National Weather Service data. The domain of interest is treated as for horizontal winds.
Diffusion is calculated using appropriate turbulence models. A 2nd order solution for shearing flow can be sought when the number of meshes is limited between obstacles.
Dispersion by full gravity unless Boussinesq approximation or no gravity requested. Vertical dispersion is treated as above for horizontal dispersion.
PANCHEM, an atmospheric chemistry module for chemical reactions, is available. Photochemical reactions are used for tropospheric ozone calculations.
Physical removal is treated using dry deposition coefficients
Goldwire, H.C. Jr, T.G. McRae, G.W. Johnson, D.L. Hipple, R.P. Koopman, J.W. McClure, L.K. Morris and R.T. Cederhall, 1985. Desert Tortoise Series Data Report: 1983 Pressurized Ammonia Spills. UCID 20562, Lawrence Livermore National Laboratory; Livermore, California.
Green, S.R., 1992. Modeling Turbulent Air Flow in a Stand of Widely Spaced Trees, The PHOENICS Journal of Computational Fluid Dynamics and Its Applications, 5: 294-312.
Gryning, S.E. and E. Lyck, 1984. Atmospheric Dispersion from Elevated Sources in an Urban Area: Comparison Between Tracer Experiments and Model Calculations. Journal of Climate and Applied Meteorology, 23: 651-660.
Havens, J., T. Spicer, H. Walker and T. Williams, 1995. Validation of Mathematical Models Using Wind-Tunnel Data Sets for Dense Gas Dispersion in the Presence of Obstacles. University of Arkansas, 8th International Symposium-Loss Prevention and Safety Promotion in the Process Industries; Antwerp, Belgium.
McQuaid, J. (ed), 1985. Heavy Gas Dispersion Trials at Thorney Island. Proc. of a Symposium held at the University of Sheffield, Great Britain.
Pavitskiy, N.Y., A.A. Yakuskin and S.V. Zhubrin, 1993. Vehicular Exhaust Dispersion Around Group of Buildings. The PHOENICS Journal of Computational Fluid Dynamics and Its Applications, 6: 270-285.
Tripathi, S., 1994. Evaluation of Fluidyn-PANACHE on Heavy Gas Dispersion Test Case. Seminar on Evaluation of Models of Heavy Gas Dispersion Organized by European Commission; Mol, Belgium.
Environmental Protection Agency, 1992. User's Manual for the Plume Visibility Model, PLUVUE II (Revised). EPA Publication No. EPA-454/B-92-008, (NTIS PB93-188233). U.S. Environmental Protection Agency, Research Triangle Park, NC.
This model code is available on the Support Center for Regulatory Air Models Bulletin Board System and also on diskette (as PB 90-500778) from the National Technical Information Service (see section B.0).
The Plume Visibility Model (PLUVUE II) is used for estimating visual range reduction and atmospheric discoloration caused by plumes consisting of primary particles, nitrogen oxides and sulfur oxides emitted from a single emission source. PLUVUE II uses Gaussian formulations to predict transport and dispersion. The model includes chemical reactions, optical effects and surface deposition. Four types of optics calculations are made: horizontal and non-horizontal views through the plume with a sky viewing background; horizontal views through the plume with white, gray and black viewing backgrounds; and horizontal views along the axis of the plume with a sky viewing background.
The Plume Visibility Model (PLUVUE II) may be used on a case-by-case basis as a third level screening model. When applying PLUVUE II, the following precautions should be taken:
1. Treat the optical effects of NO
2. Examine the visual impact of the plume in 0.1 (or 0), 0.5, and 1.0 times the expected level of particulate matter in the background air.
3. Examine the visual impact of the plume over the full range of observer-plume sun angles.
4. The user should consult the appropriate Federal Land Manager when using PLUVUE II to assess visibility impacts in a Class I area.
Source data requirements are: location and elevation; emission rates of SO
Meteorological data requirements are: stability class, wind direction (for an observer-based run), wind speed, lapse rate, air temperature, relative humidity, and mixing height.
Other data requirements are: ambient background concentrations of NO
Receptor (observer) data requirements are: location, terrain elevation at points along plume trajectory, white, gray, and black viewing backgrounds, the distance from the observer to the terrain observed behind the plume.
Printed output includes plume concentrations and visual effects at specified downwind distances for calculated or specified lines of sight.
PLUVUE II is a Gaussian plume model. Visibility impairment is quantified once the spectral light intensity has been calculated for the specific lines of sight. Visibility impairment includes visual range reduction, plume contrast, relative coloration of a plume to its viewing background, and plume perceptibility due to its contrast and color with respect to a viewing background.
PLUVUE II treats NO, NO
For performing the optics calculations at selected points along the plume trajectory, PLUVUE II has two modes: plume based and observer based calculations. The major difference is the orientation of the viewer to the source and the plume.
Briggs (1969, 1971, 1972) final plume rise equations are used.
User-specified wind speed (and direction for an observer-based run) are assumed constant for the calculation.
Vertical wind speed is assumed equal to zero.
Constant, uniform (steady-state) wind is assumed for each hour. Straight line plume transport is assumed to all downwind distances.
Rural dispersion coefficients from Turner (1969) are used, with no adjustment for surface roughness. Six stability classes are used.
The chemistry of NO, NO
Dry deposition of gaseous and particulate pollutants is treated using deposition velocities.
Bergstrom, R.W., C. Seigneur, B.L. Babson, H.Y. Holman and M.A. Wojcik, 1981. Comparison of the Observed and Predicted Visual Effects Caused by Power Plant Plumes. Atmospheric Environment, 15: 2135-2150.
Bergstrom, R.W., Seigneur, C.D. Johnson and L.W. Richards, 1984. Measurements and Simulations of the Visual Effects of Particulate Plumes. Atmospheric Environment, 18(10): 2231-2244.
Seigneur, C., R.W. Bergstrom and A.B. Hudischewskyj, 1982. Evaluation of the EPA PLUVUE Model and the ERT Visibility Model Based on the 1979 VISTTA Data Base. EPA Publication No. EPA-450/4-82-008. U.S. Environmental Protection Agency, Research Triangle Park, NC.
White, W.H., C. Seigneur, D.W. Heinold, M.W. Eltgroth, L.W. Richards, P.T. Roberts, P.S. Bhardwaja, W.D. Conner and W.E. Wilson, Jr, 1985. Predicting the Visibility of Chimney Plumes: An Inter-comparison of Four Models with Observations at a Well-Controlled Power Plant. Atmospheric Environment, 19: 515-528.
Petersen, W.B, 1978. User's Guide for PAL—A Gaussian-Plume Algorithm for Point, Area, and Line Sources. EPA Publication No. EPA-600/4-78-013. Office of Research and Development, Research Triangle Park, NC. (NTIS No. PB 281306)
Rao, K.S. and H.F. Snodgrass, 1982. PAL-DS Model: The PAL Model Including Deposition and Sedimentation. EPA Publication No. EPA-600/8-82-023. Office of Research and Development, Research Triangle Park, NC. (NTIS No. PB 83-117739)
The computer code is available on diskette (as PB 90-500802) from the National Technical Information Service (see section B.0).
PAL-DS is an acronym for this point, area, and line source algorithm and is a method of estimating short-term dispersion using Gaussian-plume steady-state assumptions. The algorithm can be used for estimating concentrations of non-reactive pollutants at 99 receptors for averaging times of 1 to 24 hours, and for a limited number of point, area, and line sources (99 of each type). This algorithm is not intended for application to entire urban areas but is intended, rather, to assess the impact on air quality, on scales of tens to hundreds of meters, of portions of urban areas such as shopping centers, large parking areas, and airports. Level terrain is assumed. The Gaussian point source equation estimates concentrations from point sources after determining the effective height of emission and the upwind and crosswind distance of the source from the receptor. Numerical integration of the Gaussian point source equation is used to determine concentrations from the four types of line sources. Subroutines are included that estimate concentrations for multiple lane line and curved path sources, special line sources (line sources with endpoints at different heights above ground), and special curved path sources. Integration over the area source, which includes edge effects from the source region, is done by considering finite line sources perpendicular to the wind at intervals upwind from the receptor. The crosswind integration is done analytically; integration upwind is done numerically by successive approximations.
The PAL-DS model utilizes Gaussian plume-type diffusion-deposition algorithms based on analytical solutions of a gradient-transfer model. The PAL-DS model can treat deposition of both gaseous and suspended particulate pollutants in the plume since gravitational settling and dry deposition of the particles are explicitly accounted for. The analytical diffusion-deposition expressions listed in this report in the limit when pollutant settling and deposition velocities are zero, they reduce to the usual Gaussian plume diffusion algorithms in the PAL model.
PAL-DS can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. PAL-DS must be executed in the equivalent mode.
PAL-DS can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section 3.2, that PAL-DS is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data: point-sources—emission rate, physical stack height, stack gas temperature, stack gas velocity, stack diameter, stack gas volume flow, coordinates of stack, initial
Meteorological data: wind profile exponents, anemometer height, wind direction and speed, stability class, mixing height, air temperature, and hourly variations in emission rate.
Receptor data: receptor coordinates.
Printed output includes:
Hourly concentration and deposition flux for each source type at each receptor; and
Average concentration for up to 24 hours for each source type at each receptor.
PAL-DS is a Gaussian plume model.
PAL-DS may be used to model non-reactive pollutants.
Up to 99 sources of each of 6 source types: point, area, and 4 types of line sources.
Source and receptor coordinates are uniquely defined.
Unique stack height for each source.
Coordinates of receptor locations are user defined.
Briggs final plume rise equations are used.
Fumigation and downwash are not treated.
If plume height exceeds mixing height, concentrations are assumed equal to zero.
Surface concentrations are set to zero when the plume centerline exceeds mixing height.
User-supplied hourly wind data are used.
Constant, uniform (steady-state) wind is assumed within each hour. Wind is assumed to increase with height.
Assumed equal to zero.
Rural dispersion coefficients from Turner (1969) are used with no adjustments made for surface roughness.
Six stability classes are used.
Dispersion coefficients (Pasquill-Gifford) are assumed based on a 3cm roughness height.
Six stability classes are used.
Rural dispersion coefficients from Turner (1969) are used; no further adjustments are made for variation in surface roughness, transport or averaging time.
Multiple reflection is handled by summation of series until the vertical standard deviation equals 1.6 times mixing height. Uniform vertical mixing is assumed thereafter.
Not treated.
PAL-DS can treat deposition of both gaseous and suspended particulates in the plume since gravitational settling and dry deposition of the particles are explicitly accounted for.
None Cited.
Environmental Protection Agency, 1993. Reactive Plume Model IV (RPM-IV) User's Guide. EPA Publication No. EPA-454/B-93-012. U.S. Environmental Protection Agency (ESRL), Research Triangle Park, NC. (NTIS No. PB 93-217412)
The above report and model computer code are available on the Support Center for Regulatory Air Models Bulletin Board System. The model code is also available on diskette (as PB 96-502026) from the National Technical Information Service (see section B.0).
The Reactive Plume Model, RPM-IV, is a computerized model used for estimating short-term concentrations of primary and secondary reactive pollutants resulting from single or, in some special cases, multiple sources if they are aligned with the mean wind direction. The model is capable of simulating the complex interaction of plume dispersion and non-linear photochemistry. If Carbon Mechanism IV (CBM-IV) is used, emissions must be disaggregated into carbon bond classes prior to model application. The model can be run on a mainframe computer, workstation, or IBM-compatible PC with at least 2 megabytes of memory. A major feature of RPM-IV is its ability to interface with input and output files from EPA's Regional Oxidant Model (ROM) and Urban Airshed Model (UAM) to provide an internally consistent set of modeled ambient concentrations for various pollutant species.
There is no specific recommendation at the present time. RPM-IV may be used on a case-by-case basis.
Source data requirements are: emission rates, name, and molecular weight of each species of pollutant emitted; ambient pressure, ambient temperature, stack height, stack diameter, stack exit velocity, stack gas temperature, and location.
Meteorological data requirements are: wind speeds, plume widths or stability classes, photolytic rate constants, and plume depths or stability classes.
Receptor data requirements are: downwind distances or travel times at which calculations are to be made.
Initial concentration of all species is required, and the specification of downwind ambient concentrations to be entrained by the plume is optional.
Short-term concentrations of primary and secondary pollutants at either user specified time increments, or user specified downwind distances.
Reactive Gaussian plume model.
Currently, using the Carbon Bond Mechanism (CBM-IV), 34 species are simulated (82 reactions), including NO, NO
Single point source.
Single area or volume source.
Multiple sources can be simulated if they are lined up along the wind trajectory.
Predicted concentrations are obtained at a user specified time increment, or at user specified downwind distances.
Briggs (1971) plume rise equations are used.
User specifies wind speeds as a function of time.
Not treated.
User specified plume widths, or user may specify stability and widths will be computed using Turner (1969).
User specified plume depths, or user may specify stability in which case depths will be calculated using Turner (1969). Note that vertical uniformity in plume concentration is assumed.
RPM-IV has the flexibility of using any user input chemical kinetic mechanism. Currently it is run using the chemistry of the Carbon Bond Mechanism, CBM-IV (Gery et al., 1988). The CBM-IV mechanism, as incorporated in RPM-IV, utilizes an updated simulation of PAN chemistry that includes a peroxy-peroxy radical termination reaction, significant when the atmosphere is NO
Not treated.
Stewart, D.A. and M-K Liu, 1981. Development and Application of a Reactive Plume Model. Atmospheric Environment, 15: 2377-2393.
PEI Associates, 1988. User's Guide to SDM-A Shoreline Dispersion Model. EPA Publication No. EPA-450/4-88-017. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 89-164305)
The model code is available on the Support Center for Regulatory Air Models Bulletin Board System (see section B.0).
SDM is a hybrid multi-point Gaussian dispersion model that calculates source impact for those hours during the year when fumigation events are expected using a special fumigation algorithm and the MPTER regulatory model for the remaining hours (see appendix A).
SDM may be used on a case-by-case basis for the following applications:
• Tall stationary point sources located at a shoreline of any large body of water;
• Rural or urban areas;
• Flat terrain;
• Transport distances less than 50 km;
• 1-hour to 1-year averaging times.
Source data: location, emission rate, physical stack height, stack gas exit velocity, stack inside diameter, stack gas temperature and shoreline coordinates.
Meteorological data: hourly values of mean wind speed within the Thermal Internal Boundary Layer (TIBL) and at stack height; mean potential temperature over land and over water; over water lapse rate; and surface sensible heat flux. In addition to these meteorological data, SDM access standard NWS surface and upper air meteorological data through the RAMMET preprocessor.
Receptor data: coordinates for each receptor.
Printed output includes the MPTER model output as well as: special shoreline fumigation applicability report for each day and source; high-five tables on the standard output with “F” designation next to the concentration if that averaging period includes a fumigation event.
SDM is hybrid Gaussian model.
SDM may be used to model primary pollutants. Settling and deposition are not treated.
SDM applies user-specified locations of stationary point sources and receptors. User input stack height, shoreline orientation and source characteristics for each source. No topographic elevation is input; flat terrain is assumed.
SDM uses Briggs (1975) plume rise for final rise. SDM does not treat stack tip or building downwash.
Constant, uniform (steady-state) wind is assumed for an hour. Straight line plume transport is assumed to all downwind distances. Separate wind speed profile exponents (EPA, 1980) for both rural and urban cases are assumed.
Vertical wind speed is assumed equal to zero.
For the fumigation algorithm coefficients based on Misra (1980) and Misra and McMillan (1980) are used for plume transport in stable air above TIBL and based on Lamb (1978) for transport in the unstable air below the TIBL. An effective horizontal dispersion coefficient based on Misra and Onlock (1982) is used. For nonfumigation periods, algorithms contained in the MPTER model are used (see appendix A).
For the fumigation algorithm, coefficients based on Misra (1980) and Misra and McMillan (1980) are used.
Chemical transformation is not included in the fumigation algorithm.
Physical removal is not explicitly treated.
Environmental Protection Agency, 1987. Analysis and Evaluation of Statistical Coastal Fumigation Models. EPA Publication No. EPA-450/4-87-002. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS PB 87-175519)
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs, Volumes I and II. EPA Publication No. EPA-903/9-82-004a and b. U.S. Environmental Protection Agency, Region III, Philadelphia, PA.
The computer code is available on the Support Center for Regulatory Air Models Bulletin Board System and on diskette (as PB 96-501986) from the National Technical Information Service (see section B.0).
SHORTZ utilizes the steady state bivariate Gaussian plume formulation for both urban and rural areas in flat or complex terrain to calculate ground-level ambient air concentrations. The model can calculate 1-hour, 2-hour, 3-hour etc. average concentrations due to emissions from stacks, buildings and area sources for up to 300 arbitrarily placed sources. The output consists of total concentration at each receptor due to emissions from each user-specified source or group of sources, including all sources. If the option for gravitational settling is invoked, analysis cannot be accomplished in complex terrain without violating mass continuity.
SHORTZ can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. SHORTZ must be executed in the equivalent mode.
SHORTZ can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using the criteria in section 3.2, that SHORTZ is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data requirements are: for point, building or area sources, location, elevation, total emission rate (optionally classified by gravitational settling velocity) and decay coefficient; for stack sources, stack height, effluent temperature, effluent exit velocity, stack radius (inner), actual volumetric flow rate, and ground elevation (optional); for building sources, height, length and width, and orientation; for area sources, characteristic vertical dimension, and length, width and orientation.
Meteorological data requirements are: wind speed and measurement height, wind profile exponents, wind direction, standard deviations of vertical and horizontal wind directions, (i.e., vertical and lateral turbulent
Receptor data requirements are: coordinates, ground elevation.
Printed output includes total concentration due to emissions from user-specified source groups, including the combined emissions from all sources (with optional allowance for depletion by deposition).
SHORTZ is a Gaussian plume model.
SHORTZ may be used to model primary pollutants. Settling and deposition of particulates are treated.
User specified locations for sources and receptors are used.
Receptors are assumed to be at ground level.
Plume rise equations of Bjorklund and Bowers (1982) are used.
Stack tip downwash (Bjorklund and Bowers, 1982) is included.
All plumes move horizontally and will fully intercept elevated terrain.
Plumes above mixing height are ignored.
Perfect reflection at mixing height is assumed for plumes below the mixing height.
Plume rise is limited when the mean wind at stack height approaches or exceeds stack exit velocity.
Perfect reflection at ground is assumed for pollutants with no settling velocity.
Zero reflection at ground is assumed for pollutants with finite settling velocity.
Tilted plume is used for pollutants with settling velocity specified. Buoyancy-induced dispersion (Briggs, 1972) is included.
Winds are assumed homogeneous and steady-state.
Wind speed profile exponents are functions of both stability class and wind speed. Default values are specified in Bjorklund and Bowers (1982).
Vertical winds are assumed equal to zero.
Horizontal plume size is derived from input lateral turbulent intensities using adjustments to plume height, and rate of plume growth with downwind distance specified in Bjorklund and Bowers (1982).
Vertical plume size is derived from input vertical turbulent intensities using adjustments to plume height and rate of plume growth with downwind distance specified in Bjorklund and Bowers (1982).
Chemical transformations are treated using exponential decay. Time constant is input by the user.
Settling and deposition of particulates are treated.
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs. EPA Publication No. EPA-903/9-82-004. EPA Environmental Protection Agency, Region III, Philadelphia, PA.
Wackter, D. and R. Londergan, 1984. Evaluation of Complex Terrain Air Quality Simulation Models. EPA Publication No. EPA-450/4-84-017. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Chock, D.P., 1980. User's Guide for the Simple Line-Source Model for Vehicle Exhaust Dispersion Near a Road. Ford Research Laboratory, Dearborn, MI.
Copies of the above reference are available without charge from: Dr. D.P. Chock, Ford Research Laboratory, P.O. Box 2053; MD-3083, Dearborn, MI 48121-2053. The short model algorithm is contained in the User's Guide.
The Simple Line-Source Model is a simple steady-state Gaussian plume model which can be used to determine hourly (or half-hourly) averages of exhaust concentrations within 100m from a roadway on a relatively flat terrain. The model allows for plume rise due to the heated exhaust, which can be important when the crossroad wind is very low. The model also utilizes a new set of vertical dispersion parameters which reflects the influence of traffic-induced turbulence.
The Simple Line-Source Model can be used if it can be demonstrated to estimate concentrations equivalent to those provided by the preferred model for a given application. The model must be executed in the equivalent mode.
The Simple Line-Source Model can be used on a case-by-case basis in lieu of a preferred model if it can be demonstrated, using criteria in section 3.2, that it is more appropriate for the specific application. In this case the model options/modes which are most appropriate for the application should be used.
Source data requirements are: emission rate per unit length per lane, the number of lanes on each road, distances from lane centers to the receptor, source and receptor heights.
Meteorological data requirements are: buoyancy flux, ambient stability condition, ambient wind and its direction relative to the road.
Receptor data requirements are: distance and height above ground.
Printed output includes hourly or (half-hourly) concentrations at the receptor due to exhaust emission from a road (or a system of roads by summing the results from repeated model applications).
The Simple Line-Source Model is a Gaussian plume model.
The Simple Line-Source Model can be used to model primary pollutants. Settling and deposition are not treated.
The Simple Line-Source Model treats arbitrary location of line sources and receptors.
Plume-rise formula adequate for a heated line source is used.
The Simple Line-Source Model uses user-supplied hourly (or half-hourly) ambient wind speed and direction. The wind measurements are from a height of 5 to 10m.
Vertical wind speed is assumed equal to zero.
Horizontal dispersion parameter is not used.
A vertical dispersion parameter is used which is a function of stability and wind-road angle. Three stability classes are used: unstable, neutral and stable. The parameters take into account the effect of traffic-generated turbulence (Chock, 1980).
Not treated.
Not treated.
Chock, D.P., 1978. A Simple Line-Source Model for Dispersion Near Roadways. Atmospheric Environment, 12: 823-829.
Sistla, G., P. Samson, M. Keenan and S.T. Rao, 1979. A Study of Pollutant Dispersion Near Highways. Atmospheric Environment, 13: 669-685.
Ermak, D.L., 1990. User's Manual for SLAB: An Atmospheric Dispersion Model for Denser-than-Air Releases (UCRL-MA-105607), Lawrence Livermore National Laboratory.
The computer code can be obtained from: Energy Science and Technology Center, P.O. Box 1020, Oak Ridge, TN 37830, Phone (615) 576-2606.
The User's Manual (as DE 91-008443) can be obtained from the National Technical Information Service. The computer code is also available on the Support Center for Regulatory Air Models Bulletin Board System (Public Upload/ Download Area; see section B.0.)
The SLAB model is a computer model, PC-based, that simulates the atmospheric dispersion of denser-than-air releases. The types of releases treated by the model include a ground-level evaporating pool, an elevated horizontal jet, a stack or elevated vertical jet and an instantaneous volume source. All sources except the evaporating pool may be characterized as aerosols. Only one type of release can be processed in any individual simulation. Also, the model simulates only one set of meteorological conditions; therefore direct application of the model over time periods longer than one or two hours is not recommended.
The SLAB model should be used as a refined model to estimate spatial and temporal distribution of short-term ambient concentration (e.g., 1-hour or less averaging times) and the expected area of exposure to
The SLAB model is executed in the batch mode. Data are input directly from an external input file. There are 29 input parameters required to run each simulation. These parameters are divided into 5 categories by the user's guide: source type, source properties, spill properties, field properties, and meteorological parameters. The model is not designed to accept real-time meteorological data or convert units of input values. Chemical property data are not available within the model and must be input by the user. Some chemical and physical property data are available in the user's guide.
Source type is chosen as one of the following: evaporating pool release, horizontal jet release, vertical jet or stack release, or instantaneous or short duration evaporating pool release.
Source property data requirements are physical and chemical properties (molecular weight, vapor heat capacity at constant pressure; boiling point; latent heat of vaporization; liquid heat capacity; liquid density; saturation pressure constants), and initial liquid mass fraction in the release.
Spill properties include: source temperature, emission rate, source dimensions, instantaneous source mass, release duration, and elevation above ground level.
Required field properties are: desired concentration averaging time, maximum downwind distance (to stop the calculation), and four separate heights at which the concentration calculations are to be made.
Meteorological parameter requirements are: ambient measurement height, ambient wind speed at designated ambient measurement height, ambient temperature, surface roughness, relative humidity, atmospheric stability class, and inverse Monin-Obukhov length (optional, only used as an input parameter when stability class is unknown).
No graphical output is generated by the current version of this program. The output print file is automatically saved and must be sent to the appropriate printer by the user after program execution. Printed output includes in tabular form:
Listing of model input data;
Instantaneous spatially-averaged cloud parameters—time, downwind distance, magnitude of peak concentration, cloud dimensions (including length for puff-type simulations), volume (or mole) and mass fractions, downwind velocity, vapor mass fraction, density, temperature, cloud velocity, vapor fraction, water content, gravity flow velocities, and entrainment velocities;
Time-averaged cloud parameters—parameters which may be used externally to calculate time-averaged concentrations at any location within the simulation domain (tabulated as functions of downwind distance);
Time-averaged concentration values at plume centerline and at five off-centerline distances (off-centerline distances are multiples of the effective cloud half-width, which varies as a function of downwind distance) at four user-specified heights and at the height of the plume centerline.
As described by Ermak (1989), transport and dispersion are calculated by solving the conservation equations for mass, species, energy, and momentum, with the cloud being modeled as either a steady-state plume, a transient puff, or a combination of both, depending on the duration of the release. In the steady-state plume mode, the crosswind-averaged conservation equations are solved and all variables depend only on the downwind distance. In the transient puff mode, the volume-averaged conservation equations are solved, and all variables depend only on the downwind travel time of the puff center of mass. Time is related to downwind distance by the height-averaged ambient wind speed. The basic conservation equations are solved via a numerical integration scheme in space and time.
Pollutants are assumed to be non-reactive and non-depositing dense gases or liquid-vapor mixtures (aerosols). Surface heat transfer and water vapor flux are also included in the model.
Only one source can be modeled at a time.
There is no limitation to the number of receptors; the downwind receptor distances are internally-calculated by the model. The SLAB calculation is carried out up to the user-specified maximum downwind distance.
The model contains submodels for the source characterization of evaporating pools, elevated vertical or horizontal jets, and instantaneous volume sources.
Plume trajectory and dispersion is based on crosswind-averaged mass, species, energy, and momentum balance equations. Surrounding terrain is assumed to be flat and of uniform surface roughness. No obstacle or building effects are taken into account.
A power law approximation of the logarithmic velocity profile which accounts for stability and surface roughness is used.
Not treated.
The crosswind dispersion parameters are calculated from formulas reported by Morgan et al. (1983), which are based on experimental data from several sources. The formulas account for entrainment due to atmospheric turbulence, surface friction, thermal convection due to ground heating, differential motion between the air and the cloud, and damping due to stable density stratification within the cloud.
The horizontal dispersion parameters are calculated from formulas similar to those described for vertical dispersion, also from the work of Morgan et al. (1983).
The thermodynamics of the mixing of the dense gas or aerosol with ambient air (including water vapor) are treated. The relationship between the vapor and liquid fractions within the cloud is treated using the local thermodynamic equilibrium approximation. Reactions of released chemicals with water or ambient air are not treated.
Not treated.
Blewitt, D.N., J.F. Yohn and D.L. Ermak, 1987. An Evaluation of SLAB and DEGADIS Heavy Gas Dispersion Models Using the HF Spill Test Data. Proceedings, AIChE International Conference on Vapor Cloud Modeling, Boston, MA, November, pp. 56-80.
Ermak, D.L., S.T. Chan, D.L. Morgan and L.K. Morris, 1982. A Comparison of Dense Gas Dispersion Model Simulations with Burro Series LNG Spill Test Results. J. Haz. Matls., 6: 129-160.
Zapert, J.G., R.J. Londergan and H. Thistle, 1991. Evaluation of Dense Gas Simulation Models. EPA Publication No. EPA-450/4-90-018. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Harrison, Halstead, 1992. “A User's Guide to WYNDvalley 3.11, an Eulerian-Grid Air-Quality Dispersion Model with Versatile Boundaries, Sources, and Winds,” WYNDsoft Inc., Mercer Island, WA.
Copies of the user's guide and the executable model computer codes are available at a cost of $295.00 from: WYNDsoft, Incorporated, 6333 77th Avenue, Mercer Island, WA 98040, Phone: (206) 232-1819.
WYNDvalley 3.11 is a multi-layer (up to five vertical layers) Eulerian grid dispersion model that permits users flexibility in defining borders around the areas to be modeled, the boundary conditions at these borders, the intensities and locations of emissions sources, and the winds and diffusivities that affect the dispersion of atmospheric pollutants. The model's output includes gridded contour plots of pollutant concentrations for the highest brief episodes (during any single time step), the highest and second-highest 24-hour averages, averaged dry and wet deposition fluxes, and a colored “movie” showing evolving dispersal of pollutant concentrations, together with temporal plots of the concentrations at specified receptor sites and statistical inference of the probabilities that standards will be exceeded at those sites. WYNDvalley is implemented on IBM compatible microcomputers, with interactive data input and color graphics display.
WYNDvalley may be used on a case-by-case basis to estimate concentrations during valley stagnation periods of 24 hours or longer. Recommended inputs are listed below.
Input data, including model options, modeling domain boundaries, boundary conditions, receptor locations, source locations, and emission rates, may be entered interactively, or through existing template files from a previous run. Meteorological data, including wind speeds, wind directions, rain rates (optionally, for wet deposition calculations), and time of day and year, may be of arbitrary time increment (usually an hour) and are entered into the model through an external meteorological data file. Optionally, users may specify diffusivities and
Output from WYNDvalley includes gridded contour maps of the highest pollutant concentrations at each time step and the highest and second-highest 24-hour average concentrations. Output also includes the deposition patterns for wet, dry, and total fluxes of the pollutants to the surface, integrated over the simulation period. A running “movie” of the concentration patterns is displayed on the screen (with optional printout) as they evolve during the simulation. Output files include tables of daily-averaged pollutant concentrations at every modeled grid cell, and of hourly concentrations at up to eight specified receptors. Statistical analyses are performed on the hourly and daily data to estimate the probabilities that specified levels will be exceeded more than once during an arbitrary number of days with similar weather.
WYNDvalley is a three dimensional Eulerian grid model.
WYNDvalley may be used to model any inert pollutant.
Source and receptors may be located anywhere within the user-defined modeling domain. All point and area sources, or portions of an area source, within a given grid cell are summed to define a representative emission rate for that cell. Concentrations are calculated for each and every grid cell in the modeling domain. Up to eight grid cells may be selected as receptors, for which time histories of concentration and deposition fluxes are determined, and probabilities of exceedance are calculated.
Emissions for buoyant point sources are placed by the user in a grid cell which best reflects the expected effective plume height during stagnation conditions. Five vertical layers are available to the user.
During each time step in the model, the winds are assumed to be uniform throughout the modeling domain. Numerical diffusion is minimized in the advection algorithm. To account for terrain effects on winds and dispersion, an ad hoc algorithm is employed in the model to distribute concentrations near boundaries.
Winds are assumed to be constant with height.
Horizontal eddy diffusion coefficients may be entered explicitly by the user at every time step. Alternatively, a default algorithm may be invoked to estimate these coefficients from the wind velocities and their variances.
Vertical eddy diffusion coefficients and a top-of-model boundary condition may be entered explicitly by the user at every time step. Alternatively, a default algorithm may be invoked to estimate these coefficients from the horizontal wind velocities and their variances, and from an empirical time-of-day correction derived from temperature gradient measurements and Monin-Obukhov similarities.
Chemical transformation is not explicitly treated by WYNDvalley.
WYNDvalley optionally simulates both wet and dry deposition. Dry deposition is proportional to concentration in the lowest layer, while wet deposition is proportional to rain rate and concentration in each layer. Appropriate coefficients (deposition velocities and washout ratios) are input by the user.
Harrison, H., G. Pade, C. Bowman and R. Wilson, 1990. Air Quality During Stagnations: A Comparison of RAM and WYNDvalley with PM-10 Measurements at Five Sites. Journal of the Air & Waste Management Association, 40: 47-52.
Maykut, N. et al., 1990. Evaluation of the Atmospheric Deposition of Toxic Contaminants to Puget Sound. State of Washington, Puget Sound Water Quality Authority, Seattle, WA.
Yoshida, C., 1990. A Comparison of WYNDvalley Versions 2.12 and 3.0 with PM-10 Measurements in Six Cities in the Pacific Northwest. Lane Regional Air Pollution Authority, Springfield, OR.
Beals, G.A., 1971. A Guide to Local Dispersion of Air Pollutants. Air Weather Service Technical Report
Bjorklund, J.R. and J.F. Bowers, 1982. User's Instructions for the SHORTZ and LONGZ Computer Programs. EPA Publication No. EPA-903/9-82-004a and b. U.S. Environmental Protection Agency, Region III, Philadelphia, PA.
Briggs, G.A., 1969. Plume Rise. U.S. Atomic Energy Commission Critical Review Series, Oak Ridge National Laboratory, Oak Ridge, TN. (NTIS No. TID-25075)
Briggs, G.A., 1971. Some Recent Analyses of Plume Rise Observations. Proceedings of the Second International Clean Air Congress, edited by H.M. Englund and W.T. Berry. Academic Press, New York, NY.
Briggs, G.A., 1972. Discussion on Chimney Plumes in Neutral and Stable Surroundings. Atmospheric Environment, 6: 507-510.
Briggs, G.A., 1974. Diffusion Estimation for Small Emissions. USAEC Report ATDL-106. U.S. Atomic Energy Commission, Oak Ridge, TN.
Briggs, G.A., 1975. Plume Rise Predictions. Lectures on Air Pollution and Environmental Impact Analyses. American Meteorological Society, Boston, MA, pp. 59-111.
Briggs, G.A., 1984. Plume Rise and Buoyancy Effects. Atmospheric Science and Power Production, Darryl Randerson (Ed.). DOE Report DOE/TIC-27601, Technical Information Center, Oak Ridge, TN. (NTIS No. DE84005177)
Carpenter, S.B., T.L. Montgomery, J.M. Leavitt, W.C. Colbaugh and F.W. Thomas, 1971. Principal Plume Dispersion Models: TVA Power Plants. Journal of Air Pollution Control Association, 21: 491-495.
Chock, D.P., 1980. User's Guide for the Simple Line-Source Model for Vehicle Exhaust Dispersion Near a Road. Environmental Science Department, General Motors Research Laboratories, Warren, MI.
Colenbrander, G.W., 1980. A Mathematical Model for the Transient Behavior of Dense Vapor Clouds, 3rd International Symposium on Loss Prevention and Safety Promotion in the Process Industries, Basel, Switzerland.
DeMarrais, G.A., 1959. Wind Speed Profiles at Brookhaven National Laboratory. Journal of Applied Meteorology, 16: 181-189.
Ermak, D.L., 1989. A Description of the SLAB Model, presented at JANNAF Safety and Environmental Protection Subcommittee Meeting, San Antonio, TX, April, 1989.
Gery, M.W., G.Z. Whitten and J.P. Killus, 1988. Development and Testing of CBM-IV for Urban and Regional Modeling. EPA Publication No. EPA-600/3-88-012. U.S. Environmental Protection Agency, Research Triangle Park, NC. (NTIS No. PB 88-180039)
Gery, M.W., G.Z. Whitten, J.P. Killus and M.C. Dodge, 1989. A Photochemical Kinetics Mechanism for Urban and Regional Scale Computer Modeling. Journal of Geophysical Research, 94: 12,925-12,956.
Gifford, F.A. and S.R. Hanna, 1970. Urban Air Pollution Modeling. Proceedings of the Second International Clean Air Congress, Academic Press, Washington, D.C.; pp. 140-1151.
Gifford, F.A., 1975. Atmospheric Dispersion Models for Environmental Pollution Applications. Lectures on Air Pollution and Environmental Impact Analyses. American Meteorological Society, Boston, MA.
Green, A.E., Singhal R.P. and R. Venkateswar, 1980. Analytical Extensions of the Gaussian Plume Model. Journal of the Air Pollution Control Association, 30: 773-776.
Heffter, J.L., 1965. The Variations of Horizontal Diffusion Parameters with Time for Travel Periods of One Hour or Longer. Journal of Applied Meteorology, 4: 153-156.
Heffter, J.L., 1980. Air Resources Laboratories Atmospheric Transport and Dispersion Model (ARL-ATAD). NOAA Technical Memorandum ERL ARL-81. Air Resources Laboratories, Silver Spring, MD.
Irwin, J.S., 1979a. Estimating Plume Dispersion—A Recommended Generalized Scheme. Fourth Symposium on Turbulence, Diffusion and Air Pollution, Reno, Nevada.
Irwin, J.S., 1979b. A Theoretical Variation of the Wind Profile Power-Law Exponent as a Function of Surface Roughness and Stability. Atmospheric Environment, 13: 191-194.
MacCready, P.B., Baboolal, L.B. and P.B. Lissaman, 1974. Diffusion and Turbulence Aloft Over Complex Terrain. Preprint Volume, AMS Symposium on Atmospheric Diffusion and Air Pollution, Santa Barbara, CA. American Meteorological Society, Boston, MA.
Moore, G.E., T.E. Stoeckenius and D.A. Stewart, 1982. A Survey of Statistical Measures of Model Performance and Accuracy for Several Air Quality Models. EPA Publication No. EPA-450/4-83-001. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Morgan, D.L., Jr., L.K. Morris and D.L. Ermak, 1983. SLAB: A Time-Dependent Computer Model for the Dispersion of Heavy Gas Released in the Atmosphere, UCRL-53383, Lawrence Livermore National Laboratory, Livermore, CA.
Pasquill, F., 1976. Atmospheric Dispersion Parameters in Gaussian Plume Modeling, Part II. EPA Publication No. EPA-600/4-76-030b. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Slade, D.H., 1968.
Turner, D.B., 1964. A Diffusion Model of An Urban Area. Journal of Applied Meteorology, 3: 83-91.
Turner, D.B., 1969. Workbook of Atmospheric Dispersion Estimates. PHS Publication No. 999-AP-26. U.S. Environmental Protection Agency, Research Triangle Park, NC.
Van Dop, H., 1992. Buoyant Plume Rise in a Lagrangian Frame Work. Atmospheric Environment, 26A: 1335-1346.
This checklist recommends a standardized set of data and a standard basic level of analysis needed for PSD applications and SIP revisions. The checklist implies a level of detail required to assess both PSD increments and the NAAQS. Individual cases may require more or less information and the Regional Meteorologist should be consulted at an early stage in the development of a data base for a modeling analysis.
At pre-application meetings between source owner and reviewing authority, this checklist should prove useful in developing a consensus on the data base, modeling techniques and overall technical approach prior to the actual analyses. Such agreement will help avoid misunderstandings concerning the final results and may reduce the later need for additional analyses.
1. Source location map(s)
• Urban areas
• PSD Class I areas
• Nonattainment areas
• Topographic features (terrain, lakes, river valleys, etc.)
• Other major existing sources
• Other major sources subject to PSD requirements
• NWS meteorological observations (surface and upper air)
• On-site/local meteorological observations (surface and upper air)
• State/local/on-site air quality monitoring locations
• Plant layout on a topographic map covering a 1km radius of the source with information sufficient to determine GEP stack heights
2. Information on urban/rural characteristics:
• Land use within 3km of source classified according to Auer (1978): Correlation of land use and cover with meteorological anomalies. Journal of Applied Meteorology, 17: 636-643.
• Population
−> total
−> density
• Based on current guidance determination of whether the area should be addressed using urban or rural modeling methodology
3. Emission inventory and operating/design parameters for major sources within region of significant impact of proposed site (same as required for applicant)
• Actual and allowable annual emission rates (g/s) and operating rates
• Maximum design load short-term emission rate (g/s)
• Associated emissions/stack characteristics as a function of load for maximum, average, and nominal operating conditions if stack height is less than GEP or located in complex terrain. Screening analyses as footnoted above or detailed analyses, if necessary, must be employed to determine the constraining load condition (e.g., 50%, 75%, or 100% load) to be relied upon in the short-term modeling analysis.
—location (UTM's)
—height of stack (m) and grade level above MSL
—stack exit diameter (m)
—exit velocity (m/s)
—exit temperature (°K)
• Area source emissions (rates, size of area, height of area source)
• Location and dimensions of buildings (plant layout drawing)
—to determine GEP stack height
—to determine potential building downwash considerations for stack heights less than GEP
• Associated parameters
—boiler size (megawatts, pounds/hr. steam, fuel consumption, etc.)
—boiler parameters (% excess air, boiler type, type of firing, etc.)
—operating conditions (pollutant content in fuel, hours of operation, capacity factor, % load for winter, summer, etc.)
—pollutant control equipment parameters (design efficiency, operation record, e.g., can it be bypassed?, etc.)
• Anticipated growth changes
4. Air quality monitoring data:
• Summary of existing observations for latest five years (including any additional quality assured measured data which can be obtained from any State or local agency or company)
• Comparison with standards
• Discussion of background due to uninventoried sources and contributions from outside the inventoried area and description of the method used for determination of background (should be consistent with the Guideline)
5. Meteorological data:
• Five consecutive years of the most recent representative sequential hourly National Weather Service (NWS) data, or one or more years of hourly sequential on-site data
• Discussion of meteorological conditions observed (as applied or modified for the site-specific area, i.e., identify possible variations due to difference between the monitoring site and the specific site of the source)
• Discussion of topographic/land use influences
6. Air quality modeling analyses:
• Model each individual year for which data are available with a recommended model or model demonstrated to be acceptable on a case-by-case basis
—urban dispersion coefficients for urban areas
—rural dispersion coefficients for rural areas
• Evaluate downwash if stack height is less than GEP
• Define worst case meteorology
• Determine background and document method
—long-term
—short-term
• Provide topographic map(s) of receptor network with respect to location of all sources
• Follow current guidance on selection of receptor sites for refined analyses
• Include receptor terrain heights (if applicable) used in analyses
• Compare model estimates with measurements considering the upper ends of the frequency distribution
• Determine extent of significant impact; provide maps
• Define areas of maximum and highest, second-highest impacts due to applicant source (refer to format suggested in Air Quality Summary Tables)
−> long-term
−> short-term
7. Comparison with acceptable air quality levels:
• NAAQS
• PSD increments
• Emission offset impacts if nonattainment
8. Documentation and guidelines for modeling methodology:
• Follow guidance documents
−> appendix W to 40 CFR part 51
−> “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources, Revised” (EPA-450/R-92-019), 1992
−> “Guideline for Determination of Good Engineering Practice Stack Height (Technical Support Document for the Stack Height Regulations)” (EPA-450/4-80-023R), 1985
−> “Ambient Monitoring Guidelines for PSD” (EPA-450/4-87-007), 1987
−> Applicable sections of 40 CFR parts 51 and 52.
This appendix contains examples of EIP's which are covered by the EIP rules. Program descriptions identify key provisions which distinguish the different model program types. The examples provide additional information and guidance on various types of regulatory programs collectively referred to as EIP's. The examples include programs involving stationary, area, and mobile sources. The definition section at 40 CFR 51.491 defines an EIP as a program which may include State established emission fees or a system of marketable permits, or a system of State fees on sale or manufacture of products the use of which contributes to O
The EIP's are comprised of several elements that, in combination with each other, must insure that the fundamental principles of any regulatory program (including accountability, enforceability and noninterference with other requirements of the Act) are met. There are many possible combinations of program elements that would be acceptable. Also, it is important to emphasize that the effectiveness of an EIP is dependent upon the particular area in which it is implemented. No two areas face the same air quality circumstances and, therefore, effective strategies and programs will differ among areas.
Because of these considerations, the EPA is not specifying one particular design or type of strategy as acceptable for any given EIP. Such specific guidance would potentially discourage States (or other entities with delegated authority to administer parts of an implementation plan) from utilizing other equally viable program designs that may be more appropriate for their situation. Thus, the examples given in this Appendix are general in nature so as to avoid limiting innovation on the part of the States in developing programs tailored to individual State needs.
Another important consideration in designing effective EIP's is the extent to which different strategies, or programs targeted at different types of sources, can complement one another when implemented together as an EIP “package.” The EPA encourages States to consider packaging different measures together when such a strategy is likely to increase the overall benefits from the program as a whole. Furthermore, some activities, such as information distribution or public awareness programs, while not EIP's in and of themselves, are often critical to the success of other measures and, therefore, would be appropriate complementary components of a program package. All SIP emissions reductions credits should reflect a consideration of the effectiveness of the entire package.
There is a wide variety of programs that fall under the general heading of EIP's. Further, within each general type of program are several different basic program designs. This section describes common types of EIP's that have been implemented, designed, or discussed in the literature for stationary and mobile sources. The program types discussed below do not include all of the possible types of EIP's. Innovative approaches incorporating new ideas in existing programs, different combinations of existing program elements, or wholly new incentive systems provide additional opportunities for States to find ways to meet environmental goals at lower total cost.
One prominent class of EIP's is based upon the creation of a market in which trading of source-specific emissions requirements may occur. Such programs may include traditional rate-based emissions limits (generally referred to as emissions averaging) or overall limits on a source's total mass emissions per unit of time (generally referred to as an
Stationary, area, and mobile sources could be allowed to participate in a common emissions trading market. Programs involving emissions trading markets are particularly effective at reducing overall costs when individual affected sources face significantly different emissions control costs. A wider range in control costs among affected sources creates greater opportunities for cost-reducing trades. Thus, for example, areas which face relatively high stationary source control costs relative to mobile source control costs benefit most by including both stationary and mobile sources in a single emissions trading market.
Programs involving emissions trading markets have generally been designated as either emission allowance or emission reduction credit (ERC) trading programs. The Federal Acid Rain Program is an example of an emission allowance trading program, while “bubbles” and “generic bubbles” created under the EPA's 1986 Emission Trading Policy Statement are examples of ERC trading. Allowance trading programs can establish emission allocations to be effective at the start of a program, at some specific time in the future, or at varying levels over time. An ERC trading program requires ERC's to be measured against a pre-established emission baseline. Allowance allocations or emission baselines can be established either directly by the EIP rules or by reference to traditional regulations (e.g., RACT requirements). In either type of program, sources can either meet their EIP requirements by maintaining their own emissions within the limits established by the program, or by buying surplus allowances or ERC's from other sources. In any case, the State will need to establish adequate enforceable procedures for certifying and tracking trades, and for monitoring and enforcing compliance with the EIP.
The definition of the commodity to be traded and the design of the administrative procedures the buyer and seller must follow to complete a trade are obvious elements that must be carefully selected to help ensure a successful trading market that achieves the desired environmental goal at the lowest cost. An emissions market is defined as efficient if it achieves the environmental goal at the lowest possible total cost. Any feature of a program that unnecessarily increases the total cost without helping achieve the environmental goals causes market inefficiency. Thus, the design of an emission trading program should be evaluated not only in terms of the likelihood that the program design will ensure that the environmental goals of the program will be met, but also in terms of the costs that the design imposes upon market transactions and the impact of those costs on market efficiency.
Transaction costs are the investment in time and resources to acquire information about the price and availability of allowances or ERC's, to negotiate a trade, and to assure the trade is properly recorded and legally enforceable. All trading markets impose some level of transaction costs. The level of transaction costs in an emissions trading market are affected by various aspects of the design of the market, such as the nature of the procedures for reviewing, approving, and recording trades, the timing of such procedures (i.e., before or after the trade is made), uncertainties in the value of the allowance or credit being traded, the legitimacy of the allowance or credit being offered for sale, and the long-term integrity of the market itself. Emissions trading programs in which every transaction is different, such as programs requiring significant consideration of the differences in the chemical properties or geographic location of the emissions, can result in higher transaction costs than programs with a standardized trading commodity and well-defined rules for acceptable trades. Transaction costs are also affected by the relative ease with which information can be obtained about the availability and price of allowances or credits.
While the market considerations discussed above are clearly important in designing an efficient market to minimize the transaction costs of such a program, other considerations, such as regulatory certainty, enforcement issues, and public acceptance, also clearly need to be factored into the design of any emissions trading program.
A fee on each unit of emissions is a strategy that can provide a direct incentive for sources to reduce emissions. Ideally, fees should be set so as to result in emissions
There can be significant variations in emission fee programs. For example, potential emissions could be targeted by placing a fee on an input (e.g., a fee on the quantity and BTU content of fuel used in an industrial boiler) rather than on actual emissions. Sources paying a fee on potential emissions could be eligible for a fee waiver or rebate by demonstrating that potential emissions are not actually emitted, such as through a carbon absorber system on a coating operation.
Some fee program variations are designed to mitigate the potentially large amount of revenue that a fee program could generate. Although more complex than a simple fee program, programs that reduce or eliminate the total revenues may be more readily adopted in a SIP than a simple emission fee. Some programs lower the amount of total revenues generated by waiving the fee on some emissions. These programs reduce the total amount of revenue generated, while providing an incentive to decrease emissions. Alternatively, a program may impose higher per-unit fees on a portion of the emissions stream, providing a more powerful but targeted incentive at the same revenue levels. For example, fees could be collected on all emissions in excess of some fixed level. The level could be set as a percentage of a baseline (e.g., fees on emissions above some percentage of historical emissions), or as the lowest emissions possible (e.g., fees on emissions in excess of the lowest demonstrated emissions from the source category).
Other fee programs are “revenue neutral,” meaning that the pollution control agency does not receive any net revenues. One way to design a revenue-neutral program is to have both a fee provision and a rebate provision. Rebates must be carefully designed to avoid lessening the incentive provided by the emission fee. For example, a rebate based on comparing a source's actual emissions and the average emissions for the source category can be designed to be revenue neutral and not diminish the incentive.
Other types of fee programs collect a fee in relation to particular activities or types of products to encourage the use of alternatives. While these fees are not necessarily directly linked to the total amount of emissions from the activity or product, the relative simplicity of a usage fee may make such programs an effective way to lower emissions. An area source example is a construction permit fee for wood stoves. Such a permit fee is directly related to the potential to emit inherent in a wood stove, and not to the actual emissions from each wood stove in use. Fees on raw materials to a manufacturing process can encourage product reformulation (e.g., fees on solvent sold to makers of architectural coatings) or changes in work practices (e.g., fees on specialty solvents and degreasing compounds used in manufacturing).
Road pricing mechanisms are fee programs that are available to curtail low occupancy vehicle use, fund transportation system improvements and control measures, spatially and temporally shift driving patterns, and attempt to effect land usage changes. Primary examples include increased peak period roadway, bridge, or tunnel tolls (this could also be accomplished with automated vehicle identification systems as well), and toll discounts for pooling arrangements and zero-emitting/low-emitting vehicles.
Modifications to existing State or local tax codes, zoning provisions, and land use planning can provide effective economic incentives. Possible modifications to encourage emissions reductions cover a broad span of programs, such as accelerated depreciation of capital equipment used for emissions reductions, corporate income tax deductions or credits for emission abatement costs, property tax waivers based on decreasing emissions, exempting low-emitting products from sales tax, and limitations on parking spaces for office facilities. Mobile source strategies include waiving or lowering any of the following for zero- or low-emitting vehicles: vehicle registration fees, vehicle property tax, sales tax, taxicab license fees, and parking taxes.
A State may create incentives for reducing emissions by offering direct subsidies, grants or low-interest loans to encourage the purchase of lower-emitting capital equipment, or a switch to less polluting operating practices. Examples of such programs include clean vehicle conversions, starting shuttle bus or van pool programs, and mass transit fare subsidies. Subsidy programs often suffer from a variety of “free rider” problems. For instance, subsidies for people or firms who were going to switch to the cleaner alternative anyway lower the effectiveness of the subsidy program, or drive up the cost of achieving a targeted level of emissions reductions.
The following measures are the TCM's listed in section 108(f):
(i) Programs for improved public transit;
(ii) Restriction of certain roads or lanes to, or construction of such roads or lanes for use by, passenger buses or high occupancy vehicles;
(iii) Employer-based transportation management plans, including incentives;
(iv) Trip-reduction ordinances;
(v) Traffic flow improvement programs that achieve emission reductions;
(vi) Fringe and transportation corridor parking facilities serving multiple-occupancy vehicle programs or transit service;
(vii) Programs to limit or restrict vehicle use in downtown areas or other areas of emission concentration particularly during periods of peak use;
(viii) Programs for the provision of all forms of high-occupancy, shared-ride services;
(ix) Programs to limit portions of road surfaces or certain sections of the metropolitan area to the use of non-motorized vehicles or pedestrian use, both as to time and place;
(x) Programs for secure bicycle storage facilities and other facilities, including bicycle lanes, for the convenience and protection of bicyclists, in both public and private areas;
(xi) Programs to control extended idling of vehicles;
(xii) Programs to reduce motor vehicle emissions, consistent with title II, which are caused by extreme cold start conditions;
(xiii) Employer-sponsored programs to permit flexible work schedules;
(xiv) Programs and ordinances to facilitate non-automobile travel, provision and utilization of mass transit, and to generally reduce the need for single-occupant vehicle travel, as part of transportation planning and development efforts of a locality, including programs and ordinances applicable to new shopping centers, special events, and other centers of vehicle activity;
(xv) Programs for new construction and major reconstruction of paths, tracks or areas solely for the use by pedestrian or other non-motorized means of transportation when economically feasible and in the public interest. For purposes of this clause, the Administrator shall also consult with the Secretary of the Interior; and
(xvi) Programs to encourage the voluntary removal from use and the marketplace of pre-1980 model year light-duty vehicles and pre-1980 model light-duty trucks.
A list of CFR titles, subtitles, chapters, subchapters and parts and an alphabetical list of agencies publishing in the CFR are included in the CFR Index and Finding Aids volume to the Code of Federal Regulations which is published separately and revised annually.
Material Approved for Incorporation by Reference
Table of CFR Titles and Chapters
Alphabetical List of Agencies Appearing in the CFR
List of CFR Sections Affected
The Director of the Federal Register has approved under 5 U.S.C. 552(a) and 1 CFR Part 51 the incorporation by reference of the following publications. This list contains only those incorporations by reference effective as of the revision date of this volume. Incorporations by reference found within a regulation are effective upon the effective date of that regulation. For more information on incorporation by reference, see the preliminary pages of this volume.
All changes in this volume of the Code of Federal Regulations which were made by documents published in the Federal Register since January 1, 1986, are enumerated in the following list. Entries indicate the nature of the changes effected. Page numbers refer to Federal Register pages. The user should consult the entries for chapters and parts as well as sections for revisions.
For the period before January 1, 1986, see the “List of CFR Sections Affected, 1949-1963, 1964-1972, and 1973-1985” which is published in seven separate volumes.