[Federal Register Volume 79, Number 93 (Wednesday, May 14, 2014)]
[Proposed Rules]
[Pages 27690-27716]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-10824]
[[Page 27689]]
Vol. 79
Wednesday,
No. 93
May 14, 2014
Part II
Environmental Protection Agency
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40 CFR Part 60
Performance Specification 18--Specifications and Test Procedures for
Gaseous HCl Continuous Emission Monitoring Systems at Stationary
Sources; Proposed Rule
Federal Register / Vol. 79 , No. 93 / Wednesday, May 14, 2014 /
Proposed Rules
[[Page 27690]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 60
[EPA-HQ-OAR-2013-0696; FRL-9909-79-OAR]
RIN 2060-5689
Performance Specification 18--Specifications and Test Procedures
for Gaseous HCl Continuous Emission Monitoring Systems at Stationary
Sources
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing
performance specifications and test procedures for hydrogen chloride
continuous emission monitoring systems to provide sources and
regulatory agencies with criteria and test procedures for evaluating
the acceptability of hydrogen chloride continuous emission monitoring
systems. The proposed specification (Performance Specification 18)
includes requirements for initial acceptance including instrument
accuracy and stability assessments. This action also proposes quality
assurance procedures for hydrogen chloride continuous emission
monitoring systems used for compliance determination at stationary
sources. The quality assurance procedures (Procedure 6) specify the
minimum quality assurance requirements necessary for the control and
assessment of the quality of continuous emission monitoring systems
data submitted to the EPA.
This action would establish consistent requirements for ensuring
and assessing the quality of data measured by hydrogen chloride
continuous emission monitoring systems. The affected systems are those
used for determining compliance with emission standards for hydrogen
chloride on a continuous basis as specified in an applicable permit or
regulation. The affected industries and their North American Industry
Classification System codes are listed in the SUPPLEMENTARY INFORMATION
section of this preamble.
DATES: Comments. Comments must be received on or before June 13, 2014.
Public Hearing. The EPA will hold a public hearing on this rule if
requested. Requests for a hearing must be made by May 27, 2014.
Requests for a hearing should be made to Ms. Candace Sorrell via email
at [email protected] or by phone at (919) 541-1064. If a hearing
is requested, it will be held on May 28, 2014 at the EPA facility in
Research Triangle Park, NC.
ADDRESSES: Comments. Submit your comments, identified by Docket ID No.
EPA-HQ-OAR-2013-0696, by one of the following methods:
http://www.regulations.gov: Follow the online instructions
for submitting comments.
Email: [email protected], Attention Docket ID Number
EPA-HQ-OAR-2013-0696.
Fax: (202) 566-9744, Attention Docket ID No. EPA-HQ-OAR-
2013-0696.
Mail: U.S. Postal Service, send comments to: EPA Docket
Center, William J. Clinton (WJC) West Building, Attention Docket ID
Number EPA-HQ-OAR-2013-0696, U.S. Environmental Protection Agency, Mail
code: 28221T, 1200 Pennsylvania Ave. NW., Washington, DC 20460. Please
include a total of two copies.
Hand Delivery: U.S. Environmental Protection Agency, WJC
West Building (Air Docket), Room 3334, 1301 Constitution Ave. NW.,
Washington, DC, 20004, Attention Docket ID Number EPA-HQ-OAR-2013-0696.
Such deliveries are only accepted during the Docket's normal hours of
operation, and special arrangements should be made for deliveries of
boxed information.
Instructions. Direct your comments to Docket ID Number EPA-HQ-OAR-
2013-0696. The EPA's policy is that all comments received will be
included in the public docket without change and may be made available
online at http://www.regulations.gov, including any personal
information provided, unless the comment includes information claimed
to be Confidential Business Information (CBI) or other information
whose disclosure is restricted by statute. Do not submit information
that you consider to be CBI or otherwise protected through http://www.regulations.gov or email. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means the EPA will not know
your identity or contact information unless you provide it in the body
of your comment. If you send an email comment directly to the EPA
without going through http://www.regulations.gov, your email address
will be automatically captured and included as part of the comment that
is placed in the public docket and made available on the Internet. If
you submit an electronic comment, the EPA recommends that you include
your name and other contact information in the body of your comment and
with any disk or CD-ROM you submit. If the EPA cannot read your comment
due to technical difficulties and cannot contact you for clarification,
the EPA may not be able to consider your comment. Electronic files
should not include special characters or any form of encryption and be
free of any defects or viruses. For additional information about the
EPA's public docket, visit the EPA Docket Center homepage at: http://www.epa.gov/epahome/dockets.
Docket: The EPA has established a docket for this rulemaking under
Docket ID Number EPA-HQ-OAR-2013-0696. All documents in the docket are
listed in the regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, is not placed on the Internet and will be
publicly available only in hard copy. Publicly available docket
materials are available either electronically in regulations.gov or in
hard copy at the EPA Docket Center, WJC West Building, Room 3334, 1301
Constitution Ave. NW., Washington, DC 20004. The Public Reading Room is
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding
legal holidays. The telephone number for the Public Reading Room is
(202) 566-1744, and the telephone number for the EPA Docket Center is
(202) 566-1742.
FOR FURTHER INFORMATION CONTACT: For questions about this proposed
action, contact Ms. Candace Sorrell, Office of Air Quality Planning and
Standards, Air Quality Assessment Division (AQAD), Measurement
Technology Group, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina 27709; telephone number: (919) 541-1064;
fax number: (919) 541-0516; email address: [email protected].
SUPPLEMENTARY INFORMATION: Organization of this Document. The
information in this preamble is organized as follows:
I. General Information
A. Does this action apply to me?
B. Where can I get a copy of this document and other related
information?
C. What should I consider as I prepare my comments for the EPA?
II. Background
III. Summary of Proposed Performance Specification 18
A. What is the purpose of PS-18?
B. Who must comply with PS-18?
C. When must I comply with PS-18?
D. What are the basic requirements of PS-18?
E. What are the reporting and recordkeeping requirements for PS-
18?
IV. Summary of Proposed Procedure 6
A. What is the purpose of Procedure 6?
B. Who must comply with Procedure 6?
C. When must I comply with Procedure 6?
D. What are the basic requirements of Procedure 6?
[[Page 27691]]
E. What are the reporting and recordkeeping requirements for
Procedure 6?
V. Rationale for Selecting the Proposed Requirements of Performance
Specification 18 and Procedure 6
A. What information did we use to develop PS-18 and Procedure 6?
B. How did we select the requirements for PS-18 and Procedure 6?
C. Solicitation for Comment
VI. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
I. National Technology Transfer and Advancement Act
J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
I. General Information
A. Does this action apply to me?
The major entities that would potentially be affected by the
proposed performance specification 18 (PS-18) and the quality assurance
(QA) requirements of Procedure 6 for gaseous hydrogen chloride (HCl)
continuous emission monitoring systems (CEMS) are those entities that
are required to install a new CEMS, relocate an existing CEMS, or
replace an existing CEMS under any applicable subpart of 40 CFR parts
60, 61 or 63. Table 1 of this preamble lists the current federal rules
by subpart and the corresponding source categories to which the
proposed PS-18 and Procedure 6 potentially would apply.
Table 1--Source Categories That Would Be Subject to PS-18 and Procedure
6
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Subpart(s) Source category
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40 CFR part 60
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Subpart F......................... Portland Cement Plants.
Subpart Da........................ Fossil Fuel-Fired Electric Utility,
Industrial-Commercial-
Institutional, and Small Industrial-
Commercial-Institutional Steam
Generating Units.
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40 CFR part 63
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Subpart LLL....................... Portland Cement Manufacturing
Industry.
Subpart UUUUU..................... Coal- and Oil-fired Electric Utility
Steam Generating Units.
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The requirements of the proposed PS-18 and Procedure 6 may also
apply to stationary sources located in a state, district, reservation
or territory that adopts PS-18 or Procedure 6 in its implementation
plan.
Should PS-18 and Procedure 6 ultimately be finalized, we plan to
amend 40 CFR part 63 subpart UUUUU, National Emission Standards for
Hazardous Air Pollutants: Coal- and Oil-fired Electric Utility Steam
Generating Units to offer PS-18 and Procedure 6 as an alternative to
PS-15 for continuous monitoring of HCl. Note, however, that the
alternative test method approval process of 63.7(f) is already
available, even without any regulatory amendment, as a way for affected
facilities to request approval to use PS-18/Procedure 6 in lieu of PS-
15.
With regard to 40 CFR part 63, Subpart LLL which affects Portland
cement manufacturing facilities and includes HCl monitoring
requirements, should PS-18 and Procedure 6 be finalized, no amendments
will be needed as Subpart LLL already allows for use of any promulgated
performance specification for HCl CEMS in 40 CFR part 60, Appendix B.
Table 2 lists the corresponding North American Industry
Classification System (NAICS) codes for the source categories listed in
Table 1 of this preamble.
Table 2--NAICS for Potentially Regulated Entities
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Industry NAICS Codes
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Fossil Fuel-Fired Electric Utility Steam Generating 327310
Units............................................... \a\ 921150
Portland Cement Manufacturing Plants................. 327310
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\a\ Industry in Indian Country.
Tables 1 and 2 are not intended to be exhaustive, but rather they
provide a guide for readers regarding entities potentially affected by
this action. If you have any questions regarding the potential
applicability of the proposed PS-18 and test procedures (Procedure 6)
to a particular entity, consult the person listed in the FOR FURTHER
INFORMATION CONTACT section.
B. Where can I get a copy of this document and other related
information?
In addition to being available in the docket, an electronic copy of
this action is available on the Internet through the EPA's Technology
Transfer Network (TTN) Web site, a forum for information and technology
exchange in various areas of air pollution control. Following signature
by the EPA Administrator, the EPA will post a copy of this proposed
action on the TTN's policy and guidance page for newly proposed or
promulgated rules at: http://www.epa.gov/ttn/oarpg/t3pfpr.html.
Following publication in the Federal Register, the EPA will post the
signed proposal and key technical documents
[[Page 27692]]
on the project Web site: http://www.epa.gov/ttn/emc/proposed.html.
C. What should I consider as I prepare my comments for the EPA?
1. Submitting CBI
Do not submit information containing CBI to the EPA through http://www.regulations.gov or email. Clearly mark the part or all of the
information that you claim to be CBI. For CBI information on a disk or
CD-ROM that you will mail to the EPA, mark the outside of the disk or
CD-ROM as CBI and then identify electronically within the disk or CD-
ROM the specific information that is claimed as CBI. In addition to one
complete version of the comments that includes information claimed as
CBI, you must submit a copy of the comments that does not contain the
information claimed as CBI for inclusion in the public docket. If you
submit a CD-ROM or disk that does not contain CBI, mark the outside of
the disk or CD-ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and the EPA's
electronic public docket without prior notice. Information marked as
CBI will not be disclosed except in accordance with procedures set
forth in 40 Code of Federal Regulations (CFR) part 2. Send or deliver
information identified as CBI only to the following address: Roberto
Morales, OAQPS Document Control Officer (C404-02), OAQPS, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Attention Docket ID Number EPA-HQ-OAR-2013-0696.
2. Tips for Preparing Your Comments
When submitting comments, remember to:
Identify the rulemaking by docket number and other
identifying information (subject heading, Federal Register date and
page number).
Follow directions. Respond to specific questions and
organize comments by a section number.
Explain why you agree or disagree; suggest alternatives
and substitute language for your requested changes.
Describe any assumptions and provide any technical
information and/or data that you used.
If you estimate potential costs or burdens, explain how
you arrived at your estimate in sufficient detail to allow for it to be
reproduced.
Provide specific examples to illustrate your concerns and
suggest alternatives.
Explain your views as clearly as possible, avoiding the
use of profanity or personal threats or character assassination.
Make sure to submit your comments by the comment period
deadline.
II. Background
The EPA recently promulgated the Portland Cement Maximum Achievable
Control Technology (MACT) rule (75 FR 54970, September 9, 2010; 78 FR
10006, February 12, 2013) and the Mercury and Air Toxics Standards
(MATS) rule (77 FR 9303, February 16, 2012; 78 FR 24075, April 24,
2013). Both rules specify the use of extractive Fourier Transform
Infrared Spectroscopy (FTIR) and PS-15 when affected facilities opt or
are required to continuously measure HCl emissions. To facilitate use
of alternative technologies to FTIR and aid in measuring the low levels
of HCl specified in those rules the EPA has developed and is proposing
these new specifications and quality control (QC) procedures (PS-18 and
Procedure 6) for HCl CEMS as an alternative to the use of PS-15.
Multiple technologies are available for HCl emissions monitoring.
The goals of the proposed PS-18 and Procedure 6 are (1) to allow for
the use of different HCl CEMS sampling and analytical technologies as
long as the required performance criteria set out in the performance
specification (PS) are met; and (2) to establish consistent
requirements for ensuring and assessing the quality of data measured by
HCl CEMS.
III. Summary of Proposed Performance Specification 18
A. What is the purpose of PS-18?
Proposed PS-18 establishes the criteria to evaluate acceptable
performance of HCl CEMS at the time of installation or soon after and
when regulations require reevaluation of HCl CEMS performance.
B. Who must comply with PS-18?
You may comply with PS-18 as an alternative to other HCl CEMS
performance specifications (e.g., PS-15) allowed under an applicable
subpart if you use CEMS to monitor HCl emissions from controlled and
uncontrolled emission sources subject to HCl CEMS requirements under a
part 60, 61 or 63 regulation.
C. When must I comply with PS-18?
If you are the owner or operator of existing facilities required to
install HCl CEMS in compliance with an associated rule, regulation or
permit, you must comply with PS-18 if you choose and have these
specifications approved as an alternative to other PS required under an
applicable subpart [e.g., PS-15]. Equipment and supplies for HCl CEMS
will vary depending on the measurement technology and equipment
vendors. If you are the owner or operator of affected HCl CEMS at new
stationary sources, you must comply with either the HCl CEMS PS [e.g.,
PS-15] required by the associated rule or permit or PS-18 as an
approved alternative when you install and place into operation the
affected HCl CEMS.
D. What are the basic requirements of PS-18?
The proposed PS-18 would require owners and operators subject to
HCl CEMS requirements to: (1) Select an HCl CEMS that satisfies basic
equipment control criteria; (2) install your HCl CEMS according to the
manufacturer's specifications and the requirements set out in PS-18;
(3) verify that the instrument is functioning properly; (4) calibrate
and standardize your equipment; and (5) perform PS-18 procedures that
demonstrate initial performance requirements for the HCl CEMS. A
summary of the basic requirements is presented below.
1. HCl CEMS Equipment Selection
As noted in section III.C, PS-18 equipment and supplies for HCl
CEMS can and will vary depending on the measurement technology and
equipment vendors you select. The proposed PS-18 describes the typical
key equipment and supply components found in one or more types of HCl
CEMS. Extractive HCl CEMS typically include a sample extraction system,
sample conditioning module, HCl analyzer, diluent analyzer, system
controller, data recorder, reference gas system and moisture
measurement system. Hydrogen chloride integrated path-CEMS (HCl IP-
CEMS) typically include source temperature and pressure monitors and an
optical transmitter and receiver with or without optics to generate
longer measurement paths in the emission stream.
The proposed PS-18 defines the differing HCl CEMS equipment
components and specifies design/operation basic criteria for the
differing equipment components. For example, (1) for reference gas
systems, PS-18 specifies that, for extractive CEMS, the system must be
designed to be able to introduce reference gas flow sufficient to flood
the sampling probe and prevent entry of gas from the effluent stream;
and (2) for sample conditioning that, you must operate the module in
such a way as to keep the particle-free gas sample above the modules,
PS-18
[[Page 27693]]
specifies dew point temperature of its components. For HCl IP-CEMS, you
must operate and qualify equipment to measure source gas temperature
and pressure.
2. CEMS Measurement Location Specifications and Pretest Preparation
After you have selected the appropriate HCl CEMS for your
operations, the proposed PS-18 requires that you install the system
according to the manufacturer's specifications and as specified under
section 8.0 of PS-18. The proposed PS-18 requires that you install the
CEMS at an accessible location where the pollutant concentration or
emission rate measurements are directly representative of the HCl
emissions or can be corrected to be representative of the emissions
from the affected facility.
With regards to HCl CEMS emissions measurement location, the
proposed PS-18 specifies that it should be (1) at least two equivalent
diameters downstream of the nearest control device, point of pollution
generation or other point at which a change of pollutant concentration
may occur; and (2) at least half an equivalent diameter (calculated
according to Method 1 in Appendix A-1 to part 60) upstream from the
effluent exhaust. We are soliciting comment on alternative measurement
location requirements in this preamble (see section V.C of this
preamble).
3. HCl CEMS Measurement Range
After installation, the proposed PS-18 recommends that you check,
record and document the continuous emissions measurement range of the
HCl CEMS to verify that the instrument is functioning correctly.
Performance Specification 18 requires that the data collection device
output range include zero and the upper limit of the measurement range.
4. HCl CEMS Performance Requirements and Procedures
After you have installed, set up, verified, and calibrated your HCl
CEMS, the proposed PS-18 requires that you follow specified performance
tests and procedures for the initial demonstration of your HCl CEMS and
subsequent performance evaluations of your HCl CEMS. In general, the
proposed PS-18 requires that: (1) Technology used to measure gaseous
HCl provides a distinct response (DR) and addresses any appropriate
interference correction(s); (2) the relative accuracy (RA) be
established against a reference method (RM); and (3) dynamic spiking
(DS) into the CEMS using a National Institute of Standards and
Technology (NIST) traceable standard may be required to demonstrate
initial performance at sources with emissions near the detection level
of the CEMS and for ongoing QA tests. Specific proposed PS-18 test
procedures are outlined below.
Interference Test. You must test to detect analyzer
responses to interferences not adequately accounted for in the
calibration procedure that may cause measurement bias. The combined
interference response for the analyzer used for the test must not be
greater than 3.0 percent of the equivalent HCl
concentration used for the interference test.
Beam Intensity Test for Integrated Patch CEMS (IP-CEMS).
For IP-CEMS, you must establish the light attenuation tolerance of your
system and demonstrate that the HCl response is independent of the beam
intensity. The percent difference during the attenuated light
calibration check must not be more than 3.0 percent of the
measured concentration with no attenuation used for the test.
Temperature Measurement Verification Procedure for IP-
CEMS. You must perform a temperature verification test as part of
initial installation and verification procedures for an IP-CEMS.
Temperature measurement must agree with a NIST traceable calibrated
temperature measuring device within 2.8 [deg]C (5.0 [deg]F).
Pressure Measurement Verification Test for IP-CEMS. You
must conduct a pressure measurement verification test if you have an
IP-CEMS. Your pressure monitor must agree with a NIST traceable
calibrated measurement device within 5 percent or <= 0.12
kilopascals (0.5 inches of water column), whichever is greater. For
stack pressure verification, you should select a gauge or monitor that
conforms to the design requirements of American Society of Mechanical
Engineers (ASME) standard B40.100-2010, ``Pressure Gauges and Gauge
Attachments'' (incorporated by reference, see Sec. 60.17).
Level of Detection (LOD) Determination. You must determine
the minimum amount of HCl that can be detected above the background in
an HCl-free representative gas matrix (the LOD). If you choose to
perform the LOD determination test in a controlled environment, you
must verify the LOD during the initial field certification test using
the DS test procedure (included in Appendix A of the PS). You must make
three independent DS measurements at no more than five times the LOD
for the detection level verification. If you cannot detect the DS HCl
at the estimated LOD, you must increase the spike concentration
incrementally until you establish a field verified detection level
where the HCl measurement is a minimum of three times the noise for
zero HCL concentration. The field verified detection level would
replace the controlled environment LOD and would become the site- or
installation-specific LOD.
Response Time (RT) Determination. You must determine the
average upscale and downscale response time as the response time for
the system (the RT). This is the time it takes for the measurement
system, while operating normally, to respond to a known step change in
gas concentration (from a low- or zero-level to high-level gas
concentration or vice versa). Stable RT measurements are made when
measured HCl concentration is within five percent of the spike gas
concentration (i.e., the measurements must meet the 5
percent calibration error requirement; see below).
Calibration Error (CE) Test. The CE test is the mean
difference between the HCl calibration gas value and the CEMS response
at each calibration point expressed as a percentage of the span. The CE
of your HCl CEMS must be less than five percent.
Seven-Day Calibration Drift (CD) Test. Prior to conducting
an RA test on your HCl CEMS, you must perform a 7-day CD test. The
purpose of the 7-day CD test is to verify the ability of the CEMS to
maintain calibration for each of seven, 24-hour periods. The zero-level
and high-level drift for each day must be less than five percent of the
span value. You must pass each day's drift checks for seven days to
meet this requirement and each drift check must be recorded and
reported for the 7-day drift check test.
RA Test. You must determine the RA for your HCl CEMS. As
noted above, the RA must be established against an RM. The RA is the
absolute mean difference between the gas concentration determined by
the CEMS and the value determined by the RM, plus the 2.5 percent error
confidence coefficient of a series of tests divided by the average of
the RM or the applicable emission standard.
E. What are the reporting and recordkeeping requirements for PS-18?
The proposed PS-18 specifies requirements to record and report
supporting data for test procedures and calculations set out in PS-18.
For example, for systems that use a gas blender and/or liquid
evaporative calibrator to deliver HCl gas standards, PS-18 requires
that you record and report supporting data for these devices,
[[Page 27694]]
including liquid feed calibrations, liquid standard(s) concentration,
feed rate and gas flow calibrations for all diluent and HCl gas flows.
The proposed PS-18 also requires that you record and report summaries
(in tabular form) of the results of CD tests, linearity tests, RT
tests, CE tests, RA tests and optional spike recovery procedures.
Additionally, the proposed PS-18 requires that you record and report
supporting dilution system data and LOD and system limitation
verification data for installed HCl CEMS.
IV. Summary of Proposed Procedure 6
A. What is the purpose of Procedure 6?
This proposed procedure specifies the minimum QA requirements
necessary for the control and assessment of the quality of CEMS data
submitted to the EPA. The proposed Procedure 6 would have two distinct
and important purposes. First, the procedure would assess the quality
of the HCl CEMS data produced by estimating accuracy. Second, the
procedure would assist in the control and improvement of the quality of
the CEMS data by implementing QC policies and corrective actions. Both
of these purposes work together to ensure that data quality is
acceptable.
B. Who must comply with Procedure 6?
Under the proposed Procedure 6, if you are responsible for one or
more CEMS used for HCl compliance monitoring, you would be required to
meet the minimum requirements of Procedure 6 and are encouraged to
develop and implement a more extensive QA program or to continue such
programs where they already exist. The proposed Procedure 6 would apply
to any HCl CEMS that is subject to PS-18. That is, if you are required
under an applicable subpart to parts 60, 61, or 63 to install and
operate an HCl CEMS and you choose to comply with PS-18, you would be
subject to both PS-18 and Procedure 6.
C. When must I comply with Procedure 6?
If you are the owner or operator of an affected HCl CEMS, you must
comply with Procedure 6 when you install and place into operation an
HCl CEMS that is subject to PS-18 or when an existing HCl CEMS becomes
subject to PS-18.
D. What are the basic requirements of Procedure 6?
Requirements are based on proposed PS-18. Procedure 6 includes
requirements for: (1) QC plan; (2) daily quality, calibration and
measurement standardization procedures; and (3) data accuracy
assessment. A summary of the proposed basic requirements is presented
below.
1. Quality Control Plan
The proposed Procedure 6 requires that you develop and implement a
QC plan that includes written procedures and manufacturer's information
describing in detail complete, step-by-step measures that ensure
quality data. The QC plan must cover procedures and operations for
specified activities (e.g., CD checks of HCl CEMS, HCl IP-CEMS emission
source temperature and pressure accuracy). Records of these written
procedures must be maintained and available for inspection by
enforcement agencies. The proposed Procedure 6 requires either revising
the QC plan or modifying or replacing the CEMS when quality control
failures occur for two consecutive quarters.
2. Daily Quality Requirements, Calibration and Measurement Procedures
CD Assessment. You are required to check, record and
quantify the CD at two concentration values at least once daily in
accordance with the method prescribed by the manufacturer. The HCl CEMS
calibration must, at a minimum, be adjusted whenever the daily zero (or
low-level) CD or daily high-level CD exceeds two times the drift limits
of the applicable performance specification (e.g., PS-18).
Beam Intensity Requirement for HCl IP-CEMS. You must
check, record and quantify the beam intensity of your IP-CEMS at least
once daily according to manufacturer's specifications and procedures.
If the HCl CEMS is out-of-control (the beam intensity falls outside of
the operation range determined by section 11.2 of the proposed PS-18 of
part 60), you must take the necessary corrective action and verify that
the issue has been corrected (i.e., by documenting and reporting the
results of the quality control check procedure following corrective
action showing the CEMS to be operating within specifications).
CEMS Data Status During Out-of-Control Period. Procedure 6
requires that CEMS data obtained during out-of-control periods not be
used when calculating compliance with an emissions limit or counted
toward meeting minimum data availability requirements under an
applicable regulation or permit.
3. Data Accuracy Assessment
Procedure 6 requires a weekly ``above span linearity'' challenge of
the monitoring system with a certified calibration value greater than
your highest expected hourly concentration. The ``above span''
reference gas must be introduced to the measurement system at the
probe. You must record and report the results of this procedure as you
would for a daily calibration. The ``above span linearity'' challenge
must fall within 10 percent of the certified value of the reference
gas.
Temperature and Pressure Accuracy Assessment. Procedure 6
requires temperature and pressure accuracy verification for HCl IP-
CEMS. The accuracy of the temperature and pressure measurement systems
in each HCl IP-CEMS and stack pressure readings used with IP-CEMS data
need to be verified and recorded at least once each calendar quarter
(according to procedures in section 11.3 of the proposed PS-18).
Procedure 6 also requires that measurement instruments or devices used
to conduct verification of temperature or pressure measurement have an
accuracy that is traceable to NIST. If the temperature and pressure
verification exceeds criteria specified in the procedure that indicates
that the HCl IP-CEMS is out-of-control, you need to take the necessary
corrective action to eliminate the problem and verify that it has been
corrected by repeating the failed verification (i.e., by documenting
and reporting the results of the audit following corrective action
showing the CEMS to be operating within specifications).
Concentration Accuracy Auditing Requirements. Procedure 6
requires that the accuracy of each HCl CEMS be audited at least once
each calendar quarter by a relative accuracy test audit (RATA), DS
audit (DSA), a cylinder gas audit (CGA) or other acceptable alternative
approved by the Administrator. Hydrogen chloride audit gases are
required to be NIST certified or NIST-traceable. Procedure 6 also
requires a RATA to be conducted at least once every four calendar
quarters unless the affected facility is off-line. Procedure 6 would
require the analysis of RM audit samples, if they are available,
concurrently with RM tests as specified in the general provisions of
the applicable part (i.e., based on the part [i.e., part 60, 61, or 63]
that contains the subpart that requires the owner or operator to
install and operate an HCl CEMS).
Excessive Audit Inaccuracy. Procedure 6 requires
corrective actions to eliminate problem(s) when the CEMS is out-of-
control. The procedure also requires that you verify that you have
eliminated the problem(s) by documenting and reporting the results of
the audit following corrective action
[[Page 27695]]
showing the CEMS to be operating within specifications. For purposes of
excessive audit inaccuracy, a CEMS is considered out-of-control when
(1) RA is greater than 20 percent of the RM when RMavg is used in the
denominator to determine RA or greater than 15 percent when the
equivalent emission standard value in parts per million by volume wet
(ppmvw) is used in the denominator to determine RA; (2) the RA of the
DSA is greater than 15 percent if the average spike value is used to
determine RA or greater than 20 percent of the applicable emission
standard if the emission standard is used to determine RA; or (3) the
error determined by the CGA is greater than five percent of span.
Procedure 6 proposes that CEMS data collected during out-of-control
periods not be used in calculating compliance with emission limits nor
be counted towards meeting minimum data availability requirements under
an applicable regulation or permit.
Criteria for Acceptable QC Procedures. In situations where
a CEMS experiences excessive audit inaccuracies for two consecutive
quarters, the proposed procedure requires that you revise your QC
procedures, or modify or replace your CEMS.
Criteria for Optional QA Test Frequency. The proposed
Procedure 6 specifies that, if a CEMS is determined to be in-control
for eight consecutive quarters that include a minimum of two RATA, you
may revise your auditing procedures to use CGA or DSA each quarter for
eight subsequent quarters. Under this scenario, you would only be
required to perform a RATA that meets the acceptance criteria once
every two years. If a CEMS fails a RATA, CGA, or DSA, you would need to
revert to the original auditing schedule until the audit results meet
in-control criteria to start re-qualifying for the optional QA test
frequency again.
Calculations for CEMS Data Accuracy. The proposed
Procedure 6 specifies RA, CGA accuracy and DSA accuracy calculation
requirements.
E. What are the reporting and recordkeeping requirements for Procedure
6?
The proposed Procedure 6 would require that if you own or operate
an affected HCl CEMS, you must report for each CEMS the accuracy and CD
assessment results as a Data Assessment Report (DAR) (an example of a
DAR format is provided in Procedure 6; section 9.0, Figure 1). At a
minimum, the DAR must contain source owner and operator information;
identification and location of monitors in the CEMS; manufacturer and
model number of each monitor in the CEMS; assessment of CEMS data
accuracy; and date of assessment. The DAR is required to be submitted
with the report of emissions required under the applicable regulation
or permit that requires continuous emission monitoring.
V. Rationale for Selecting the Proposed Requirements of Performance
Specification 18 and Procedure 6
A. What information did we use to develop PS-18 and Procedure 6?
To develop proposed PS-18 and Procedure 6, we considered the
requirements of emission standards promulgated under 40 CFR parts 60,
61 and 63; state agency requirements for CEMS; manufacturer and vendor
recommendations; and current operational and design practices in the
industry. As part of this consideration, the EPA's Office of Air
Quality Planning and Standards (OAQPS) gathered information from
instrument and gas vendors, affected facilities, testers and regulatory
bodies with experience performing continuous measurements of HCl from
stationary sources.
Concurrent with the EPA's OAQPS' information gathering efforts, the
EPA's Office of Research and Development (ORD) conducted research to
establish additional data to support the new performance specification
and QA test procedures. As part of the EPA's ORD's research efforts,
they evaluated commercial HCl CEMS under controlled and representative
emission environments, the suitability of candidate RMs and the status
and quality of available gas standards. The ORD focused their testing
research on interference tests, LOD tests, 7-day drift, linearity,
RATAs and DS.
B. How did we select the requirements for PS-18 and Procedure 6?
Generally, the basic requirements proposed under PS-18 and
Procedure 6 for calibration error, calibration drift, RATA, and
cylinder gas audit agreement are consistent with other CEMS performance
specifications. The proposed LOD requirements are based on an adequate
safety margin so that equipment can measure quantitatively at the
compliance limit. The proposed DS requirements are consistent with
other RM recovery requirements (e.g., EPA Method 320, EPA Method 18).
The above-span calibration and linearity requirements proposed are
based on the PS-12 precedent used for mercury CEMS.
During the development of the proposed PS-18 and Procedure 6, we
evaluated all options and attempted to develop the most appropriate
performance specifications and procedures based on available
information, testing and feedback from vendors and industry regarding
the use of HCl CEMS. Although we believe this proposal includes the
most appropriate HCl CEMS performance specifications and procedures
(for use as an alternative to PS-15 for HCl CEMS), we are soliciting
comment on several issues provided in paragraph V.C of this preamble.
C. Solicitation for Comment
1. Performance Specification 18 Topics
a. Integrated Path (IP-CEMS) Line Strength Factor
Calibration error procedures proposed for IP-CEMS in PS-18 require
correcting for calibration cell path length, temperature, pressure,
line strength factor (LSM) and, if necessary, the native source gas HCl
concentration when you calculate the stack equivalent concentration of
the HCl gas measured in your calibration cell. The proposed
specification allows the use of the line LSM provided by the instrument
manufacturer or an instrument-specific LSM experimentally determined
using a heated gas cell at effective gas concentrations equivalent to
between 50 and 150 percent of the emission limit. We are soliciting
comment on approaches used by IP instrument vendors to determine LSM
and data showing the effect of LSM on the accuracy of the stack
equivalent concentration calculation.
b. Optical Measurement Path Length Determination
An IP-CEMS measures the gas concentration along an open optical
path across the stack or duct cross section. Specifically, for IP-CEMS,
measurement path is the distance of the optical path that passes
through the source gas in the stack or duct correcting for ports,
standoffs, and extensions or CEM-specific optical path length
alterations. The optical measurement path length must be measured and
not based on engineering diagrams. We are requesting information on
procedures currently available to measure the optical path length for
IP monitors that will result in an accuracy of at least 1
percent. (See PS-1 of Appendix B to Part 60 (Specifications and Test
Procedures for Continuous Opacity Monitoring Systems in Stationary
Sources); section 8.1.)
[[Page 27696]]
c. Alternative CEMS Probe Placement Locations
Section 8.3 of the proposed PS-18 specifies HCl measurement
location requirements downstream of the control device, point of
pollution generation or other point at which a change of pollutant
concentration may occur and upstream of the exhaust. We are seeking
comment and supporting data on alternative probe placement locations
such as in the breeching of the stack (i.e., in the exhaust duct or
pipe that leads from the stack) that pass the RATA requirements.
2. Appendix F Procedure 6 Topics
a. Effect of Temperature and Pressure on HCl Concentration
Determination During DS Measurements
We provided options in Appendix F Procedure 6 for initial and
ongoing quality control using DS for IP-CEMS. The procedure to perform
DS is described in Appendix A of PS-18. For IP-CEMS, dynamic spiking is
a standard addition procedure where you spike a known concentration of
HCl gas into a calibration cell. You are required to assess the
accurate recovery of HCl introduced into the measurement system in the
presence of potential interference from the flue gas sample matrix. The
measurement involves recording the combined optical signal from HCl in
the calibration cell at ambient temperature and HCl in the stack at
elevated temperature. The combination of HCl absorbance at two
different temperatures would create hybrid spectra features of both
temperatures. Based on our evaluation, we understand there can be as
much as a 10 percent difference line shape/area used for IP
measurements between instrument operating temperature near 20[deg]C and
typical stack temperatures up to 250[deg]C. We are requesting comment
on procedures that can be used to determine the concentration when IP
calibration cells contain HCl at ambient temperature (approximately
20[deg]C) or the need to heat the calibration cell to a specific
temperature during DS measurements that include absorbance for both
stack gas (HCl) at elevated temperature and ambient temperature
calibration cell HCl.
b. Use of Dynamic Spiking
The proposed PS-18 and Procedure 6 require that you audit the
accuracy of each HCl CEMS at least once each calendar quarter (except
the quarter the RATA is conducted) by a DSA, a CGA or other acceptable
alternative. Appendix A to the proposed PS-18 describes the procedure
and performance requirements for DS as a quality check for HCl CEMS. We
are proposing this option as one of three alternatives to a RATA in
three of the four quarterly QA checks required in Procedure 6. We are
soliciting comment on our proposal and data on the use of periodic DS
as an alternative to the use of a CGA.
c. Alternative QA for Low Level RM RATA Measurements
We are proposing a mandatory RATA with the appropriate RM during
initial demonstration and periodically thereafter. We are also
soliciting comment and data on alternative or additional QA that should
be performed when the stack HCl concentration is below the RM
quantitation limit.
d. Long-Term Quality Control Under Procedure 6
The proposed Appendix F to part 60 (Quality Assurance Procedure 6)
requires a RATA at least once every four calendar quarters, except in
the case where the affected facility is off-line (does not operate in
the fourth calendar quarter since the quarter of the previous RATA).
Section 5.5 of the procedure specifies that if the CEMS is in-control
for eight consecutive quarters that include a minimum of two RATA, you
may revise your auditing procedures to use CGA or DSA each quarter for
eight subsequent quarters, but you must perform at least one RATA and
demonstrate that the source meets the acceptance criteria every 2
years. We are requesting comments and data on alternative grace periods
allowed between required RATAs when your audits demonstrate that the
source has been in-control long-term under Procedure 6.
e. Method 205 to Generate Cylinder Gas Audit Concentrations for
Quarterly Audits
Section 7.3 (Reagents and Standards) of the proposed PS-18 allows
the use of diluted high concentration HCl standards to achieve the HCl
gas concentrations required in PS-18 as long as you follow Method 205
or other procedures approved by the Administrator. We are soliciting
comment and data comparing the uncertainty of gases generated by
dilution using Method 205 to the tolerance allowed for cylinder gas
audits in section 5.2.2.3 of Procedure 6 proposed for 40 CFR part 60,
Appendix F.
f. Direct Instrument Cell Calibration Checks
As noted previously, for extractive CEMS, DS involves adding a
known concentration of HCl gas at a known flow rate into the probe
sample gas stream to assess the ability of the measurement system to
recover and accurately measure HCl in the presence of potential
interference from the flue gas matrix. We are considering an
alternative that includes instrument calibration checks for extractive
CEMS and request comment and supporting data on two topics related to
calibration check procedures: (1) What is the feasibility of achieving
DS accuracy to 95 percent of the theoretical spike at the span
concentration? and (2) If calibration checks are performed at the
instrument for extractive CEMS, what is the accuracy of dynamic spike
recovery?
g. Using DS and Associated Acceptance Criteria as an Alternative to
Daily Calibration Check for Quality Assurance Procedure 6
Calibration drift is a quantitative assessment of whether your HCl
CEMS measurements are in control. Checking calibration also allows the
facility to reset the calibration and improve the consistency and
quality of HCl CEMS data. We are considering using dynamic spiking as
an alternative to direct cylinder gas assessment of calibration drift
as a measure of QC for HCl CEMS. We are taking comment and data on the
quantitative comparison of dynamic spike recovery results compared to
CD results to determine if there are comparable criteria for DS to
qualify as an alternative for CD tests.
h. Moisture Measurements To Correct HCl Results
Section 6.8 (Moisture Measurement System) of the proposed PS-18
stipulates that, if correction of the measured HCl emissions for
moisture is required, either Method 4 in Appendix A-3 of part 60 or
other moisture measurement methods approved by the Administrator will
be needed to measure stack gas moisture content. We are requesting
comment/data on conditions or situations where continuous moisture
measurements should be required to correct HCl results to the units of
the standard, and where periodic Method 4 tests or equivalent is good
enough on a periodic basis to define moisture for the entire duration
between Method 4 tests.
i. Other Initial or On-Going Procedures for IP-CEMS
We are soliciting comment/data on other initial or on-going
procedures for
[[Page 27697]]
IP-CEMS not included in the proposal that are commonly performed and
necessary to ensure data are of known and acceptable quality to
demonstrate compliance.
VI. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a ``significant regulatory action'' under the
terms of Executive Order 12866 (58 FR 51735, October 4, 1993) and is
therefore not subject to review under Executive Orders 12866 and 13563
(76 FR 3821, January 21, 2011).
B. Paperwork Reduction Act
This action does not impose an information collection burden under
the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq.
Burden is defined at 5 CFR 1320.3(b). This action provides performance
criteria and QA test procedures for assessing the acceptability of HCl
CEMS performance and data quality. These criteria and QA test
procedures do not add information collection requirements beyond those
currently required under the applicable regulation.
C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of this rule on small
entities, small entity is defined as: (1) A small business as defined
by the Small Business Administration's regulations at 13 CFR 121.201;
(2) a small governmental jurisdiction that is a government of a city,
county, town, school district or special district with a population of
less than 50,000; and (3) a small organization that is any not-for-
profit enterprise which is independently owned and operated and is not
dominant in its field.
After considering the economic impacts of this rule on small
entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. This
proposed rule will not impose any requirements on small entities. We
continue to be interested in the potential impacts of the proposed rule
on small entities and welcome comments on issues related to such
impacts.
D. Unfunded Mandates Reform Act
This action contains no federal mandates under the provisions of
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), 2 U.S.C.
1531-1538, for state, local or tribal governments or the public sector.
This action imposes no enforceable duty on any state, local or tribal
governments or the private sector. Therefore, this action is not
subject to the requirements of sections 202 or 205 of UMRA.
This action is also not subject to the requirements of section 203
of the UMRA because it contains no regulatory requirements that might
significantly or uniquely affect small governments. This rule will not
apply to such governments and will not impose any obligations upon
them.
E. Executive Order 13132: Federalism
This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states or on the distribution of power
and responsibilities among the various levels of government, as
specified in Executive Order 13132. Thus, Executive Order 13132 does
not apply to this action.
In the spirit of Executive Order 13132 and consistent with EPA
policy to promote communications between the EPA and state and local
governments, the EPA specifically solicits comment on this proposed
rule from state and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
This action does not have tribal implications, as specified in
Executive Order 13175 (65 FR 67249, November 9, 2000). This action
proposes performance specifications that can be used as an additional
option to PS-15 for HCl continuous emissions monitoring. Thus,
Executive Order 13175 does not apply to this action. The EPA solicits
additional comment on this proposed action from tribal officials.
G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks
The EPA interprets Executive Order 13045 (62 FR 19885, April 23,
1997) as applying only to regulatory actions that are based on health
or safety risks, such that the analysis required under section 5-501 of
the Executive Order has the potential to influence the regulation. This
action is not subject to Executive Order 13045 because it does not
establish an environmental standard intended to mitigate health or
safety risks.
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
This action is not subject to Executive Order 13211 (66 FR 28355
(May 22, 2001)), because it is not a significant regulatory action
under Executive Order 12866.
I. National Technology Transfer and Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Public Law 104-113, 12(d) (15 U.S.C. 272 note)
directs the EPA to use voluntary consensus standards (VCS) in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by VCS bodies. The NTTAA directs the EPA to provide Congress,
through OMB, explanations when the agency decides not to use available
and applicable VCS. This proposed rule does not involve technical
standards. Therefore, the EPA is not considering the use of any
voluntary consensus standards.
J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations
Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
federal executive policy on environmental justice. Its main provision
directs federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
The EPA has determined that this proposed rule will not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations
[[Page 27698]]
because it does not affect the level of protection provided to human
health or the environment. This proposed rule will help to ensure that
emission control devices are operated properly and maintained as
needed, thereby helping to ensure compliance with emission standards,
which would benefit all affected populations.
Performance Specification 18--Specifications and Test Procedures for
Gaseous HCl Continuous Emission Monitoring Systems at Stationary
Sources
List of Subjects in 40 CFR Part 60
Environmental protection, Administrative practice and procedure,
Air pollution control, Continuous emission monitoring systems, Hydrogen
chloride, Performance specifications, Test methods and procedures.
Dated: April 30, 2014.
Gina McCarthy,
Administrator.
For the reasons stated in the preamble, the Environmental
Protection Agency proposes to amend title 40, chapter 1 of the Code of
Federal Regulations as follows:
0
1. The authority citation for part 60 continues to read as follows:
Authority: 42 U.S.C., 7401-7671q.
0
2. Appendix B is amended by adding Performance Specification 18 and
Appendix A to Performance Specification 18 to read as follows:
Appendix B to Part 60--Performance Specifications
* * * * *
PERFORMANCE SPECIFICATION 18--PERFORMANCE SPECIFICATIONS AND TEST
PROCEDURES FOR GASEOUS HYDROGEN CHLORIDE (HCl) CONTINUOUS EMISSION
MONITORING SYSTEMS AT STATIONARY SOURCES
1.0 Scope and Application.
1.1 Analyte. This performance specification (PS) is applicable
for measuring gaseous concentrations of hydrogen chloride (HCl),
CAS: 7647-01-0, on a continuous basis in the units of the applicable
standard or in units that can be converted to units of the
applicable standard(s).
1.2 Applicability.
1.2.1 This specification is used to evaluate the acceptability
of HCl continuous emission monitoring systems (CEMS) at the time of
installation or soon after and when regulations require reevaluation
of HCl CEMS performance. The specification includes requirements for
initial acceptance including instrument accuracy and stability
assessments.
1.2.2 The Administrator may require the operator under section
114 of the Clean Air Act (CAA), to conduct CEMS performance
evaluations at other times besides the initial test to evaluate the
CEMS performance. See 40 CFR part 60, Sec. 60.13(c) and Sec.
63.8(e)(1).
1.2.3 A source that demonstrates their CEMS meets the criteria
of this PS may use the system to continuously monitor gaseous HCl.
If your HCl CEMS is capable of reporting the HCl concentration in
the units of the existing standard, no additional CEMS components
are necessary. If your HCl CEMS does not report concentrations in
the units of the existing standard, then other CEMS components
(e.g., oxygen (O2), temperature, stack gas flow, moisture
and pressure) are necessary to convert the units reported by your
HCl CEMS to the units of the standard.
1.2.4 These specification test results are intended to be valid
for the life of the system. As a result, the HCl measurement system
must be tested and operated in a configuration consistent with the
configuration that will be used for ongoing continuous emissions
monitoring.
1.2.5 Substantive changes to the system configuration require
retesting according to this PS. Examples of such conditions include,
but are not limited to: major changes in dilution ratio (for
dilution based systems); changes in catalyst materials, if used;
changes in sample conditioning, if used, such as filtering device
design or materials; changes in probe design or configuration; light
source or detector substitution; and changes in materials of
construction.
1.2.6 This specification is not designed to evaluate the ongoing
CEMS performance nor does it identify specific calibration
techniques and auxiliary procedures to assess CEMS performance over
an extended period of time. The source owner or operator is
responsible to calibrate, maintain, and operate the CEMS properly.
2.0 Summary of Performance Specification.
2.1 This specification covers the procedures that each HCl CEMS
must meet during the performance evaluation test. Installation and
measurement location specifications, data reduction procedures and
performance criteria are included.
2.2 The technology used to measure gaseous HCl must provide a
distinct response and address any appropriate interference
correction(s). It must accurately measure gaseous HCl in a
representative sample (path or point sampling) of stack effluent.
2.3 The relative accuracy (RA) must be established against a
reference method (RM) (e.g., Method 26A, Method 320, ASTM
International (ASTM) D6348-12, including mandatory annexes, or
Method 321, as appropriate for the source concentration and
category).
2.4 Dynamic spiking (DS) into the CEMS using a National
Institute of Standards and Technology (NIST) traceable standard may
be required to demonstrate performance at sources with emissions
near the detection level of the CEMS and for ongoing quality
assurance tests.
3.0 Definitions.
3.1 Calibration Cell means a gas containment cell used with
cross stack or integrated path (IP) monitors to perform precision
and calibration checks. The cell may be a removable sealed cell or
an evacuated and/or purged cell capable of exchanging calibration
and zero gases. When charged, it contains a known concentration of
HCl calibration gas. The calibration cell is filled with zero gas or
removed from the optical path during stack gas measurement.
3.2 Calibration Drift (CD) means the absolute value of the
difference between the CEMS output response and an upscale reference
or a zero-level reference, expressed as a percentage of the span
value, when the CEMS is challenged after a stated period of
operation during which no unscheduled maintenance or repair took
place. A separate CD determination must be performed for pollutant
and diluent analyzers.
3.3 Calibration Error (CE) means the mean difference between the
concentration measured by the CEMS and the known concentration from
a calibration standard, divided by the span, when the entire CEMS,
including the sampling interface, is challenged.
3.4 Calibration Range Above Span (CRAS) means the upper limit of
the measurement range. The calibration range must accommodate the DS
procedure if that option is selected. The CRAS should be a
conservatively high estimate of the range of HCl measurements
expected from the source category. The CRAS value defines the
calibration and quality assurance at the upper limit of HCl
concentration measurement. The CRAS may require a calibration
standard above span.
3.5 Centroidal Area means a central area that is geometrically
identical to the stack or duct cross section and is no greater than
ten percent of the stack or duct cross-sectional area.
3.6 Continuous Emission Monitoring System (CEMS) means the total
equipment required to measure the pollutant concentration or
emission rate continuously.
3.7 Continuous Operation means the time between periodic
maintenance when an instrument and sampling system operates without
user intervention, continuously samples flue gas, analyzes the
sample gas for HCl and related parameters (e.g., gas flow, diluent),
records measurement data, and saves the results to a computer file.
User intervention is permitted for initial set-up of sampling
system, initial calibrations, periodic calibration corrections,
periodic maintenance and periodic quality assurance audits.
3.8 Data Recorder means the portion of the CEMS that provides a
permanent record of analyzer output. The data recorder may record
other pertinent data such as effluent flow rates, various instrument
temperatures or abnormal CEMS operation. The data recorder may also
include automatic data reduction capabilities and CEMS control
capabilities.
3.9 Dynamic Spiking (DS) means the procedure where a known
concentration of HCl gas is injected into the probe sample gas
stream for extractive CEMS at a known flow rate, or used to fill a
calibration cell for in situ IP-CEMS, in order to assess the
accuracy of the measurement system in the presence of potential
interference from the flue gas sample matrix.
3.10 Independent Measurement(s) means the series of CEMS data
values taken during
[[Page 27699]]
sample gas analysis separated by two times the response time (RT) of
the CEMS.
3.11 Integrated Path CEMS (IP-CEMS) means a CEMS that measures
the gas concentration along an optical path in the stack or duct
cross section.
3.12 Interference means a compound or material in the sample
matrix other than HCl whose characteristics may bias the CEMS
measurement (positively or negatively). The interference may not
prevent the sample measurement, but could increase the analytical
uncertainty in the measured HCl concentration through reaction with
HCl or by changing the electronic signal generated during HCl
measurement.
3.13 Interference Test means the test to detect analyzer
responses to interferences that are not adequately accounted for in
the calibration procedure and may cause measurement bias.
3.14 Level of Detection (LOD) means the lowest level of
pollutant the CEMS can detect with 99 percent confidence in the
presence of typical source gas matrix interferents.
3.15 Liquid Evaporative Standard means a reference gas produced
by vaporizing NIST traceable liquid standards of known HCl
concentration and quantitatively mixing the resultant vapor with a
diluent carrier gas.
3.16 Optical Path means the route light travels from the light
source to the receiver used to make an optical CEMS sample
measurement.
3.17 Path Length means, for extractive optical CEMS, the
distance in meters of the optical path within a gas measurement
cell. For IP-CEMS, path length is the distance in meters of the
optical path that passes through the source gas in the stack or
duct.
3.18 Point CEMS means a CEMS that measures the source gas
concentration, either at a single point at the sampling probe tip or
over an optical path less than 10 percent of the equivalent diameter
of the stack or duct cross section.
3.19 Relative Accuracy (RA) means the absolute mean difference
between the gas concentration determined by the CEMS and the value
determined by the RM, plus the 2.5 percent error confidence
coefficient of a series of tests divided by the average of the RM or
the applicable emission standard.
3.20 Response Time (RT) means the time it takes for the
measurement system, while operating normally at its target sample
flow rate, dilution ratio, or data collection rate to respond to a
known step change in gas concentration, either from a low- or zero-
level to a high-level gas concentration or from a high level to a
low or zero level, and to read within five percent of the stable gas
response.
3.21 Sample Interface means the portion of the CEMS used for one
or more of the following: Sample acquisition, sample transport,
sample conditioning, optical measurement path, or protection of the
analyzer from the effects of stack gas.
3.22 Span Value means the value established by the relevant
regulatory requirement or is equal to twice the emission limit if
not otherwise specified.
3.23 Stratification means the identification of when a
measurement taken at a single point in a duct or emission stack is
different from measurements taken at multiple points that traverse
the duct or stack.
3.24 Zero gas means a calibration gas or liquid evaporative
spike with an HCl concentration that is below the LOD of the
measurement system.
4.0 Interferences.
Sample gas interferences will vary depending on the instrument
or technology used to make the measurement. Interferences must be
evaluated through the interference test in this performance
specification. Several compounds including carbon dioxide
(CO2), carbon monoxide (CO), formaldehyde
(CH2O), methane (CH4), and water
(H2O) are potential optical interferences with certain
types of HCl monitoring technology. Ammonia is a potential chemical
interference with HCl.
5.0 Safety.
The procedures required under this PS may involve hazardous
materials, operations, and equipment. This PS may not address all of
the safety issues associated with these procedures. It is the user's
responsibility to establish appropriate safety and health practices
and determine the applicable regulatory limitations prior to
performing these procedures. The CEMS users should consult
instrument operation manuals, compressed gas safety requirements
such as Occupational Safety and Health Administration regulations
and other material safety data sheets for specific precautions to be
taken.
6.0 Equipment and Supplies.
Equipment and supplies for HCl CEMS will vary depending on the
measurement technology and equipment vendors. This section provides
a description of the equipment and supplies typically found in one
or more types of HCl CEMS.
6.1 Sample Extraction System. The portion of an extractive CEMS
that collects and transports the sample to the pressure regulation
and sample conditioning module. The extraction system must deliver a
representative sample to the measurement instrument. The sample
extraction system typically consists of a sample probe and a heated
umbilical line.
6.2 Sample Conditioning Module. The portion of an extractive
CEMS that removes particulate matter and moisture from the gas
stream and provides a sample gas stream to the CEMS analysis module
or analyzer. You must keep the particle-free gas sample above the
dew point temperature of its components.
6.3 HCl Analyzer. The portion of the CEMS that detects,
quantifies and generates an output proportional to the stack gas HCl
concentration.
6.4 Diluent Analyzer. The portion of the CEMS that quantifies
stack gas concentrations of O2 or CO2. For
systems with a multi-component analyzer, the same analyzer may
quantify for all measured gases.
6.5 System Controller. The portion of the CEMS that provides
control of the analyzer and any sample extraction system components
including the probe, pressure sensing and regulation, sample
conditioning module and the sample interface.
6.6 Data Recorder. The portion of the CEMS that provides a
record of analyzer output. The data recorder may record other
pertinent data such as effluent flow rates, various instrument
temperatures or abnormal CEMS operation. The data recorder output
range must include the full range of expected HCl concentration
values in the gas stream to be sampled including zero and span
value. Multiple instrument ranges or extended calibration points to
extend the measurement range may be necessary to measure
concentrations encountered during normal process operation.
6.7 Reference Gas System(s). One or more systems may be needed
to introduce calibration gases into the measurement system. You will
use a reference gas system to introduce a known concentration of HCl
gas into the measurement system. For extractive CEMS, the system
must be able to introduce reference gas flow sufficient to flood the
sampling probe and prevent entry of gas from the effluent stream.
For IP-CEMS, the system must be able to introduce a known
concentration of HCl, at known pressure and temperature, into the
optical path used to measure HCl gas concentration.
6.8 Moisture Measurement System. If correction of the measured
HCl emissions for moisture is required, either Method 4 in Appendix
A-3 of this part or other moisture measurement methods approved by
the Administrator will be needed to measure stack gas moisture
content.
7.0 Reagents and Standards.
7.1 Reference cylinder gas(es) or liquid evaporative gas
standards used to meet the performance specifications must be
traceable to NIST.
7.2 Cylinder gas and/or liquid evaporative standards must be
used within their certification period.
7.3 High concentration HCl standards may be diluted for use in
this specification. You must document the quantitative introduction
of HCl standards into the system using Method 205 or other procedure
approved by the Administrator.
8.0 CEMS Measurement Location Specifications and Pretest
Preparation.
8.1 Prior to the start of your initial PS tests, you must ensure
that the HCl CEMS is installed according to the manufacturer's
specifications and the requirements in this section. You may use
either point or IP sampling technology.
8.2 Installation. Install the CEMS at an accessible location
where the pollutant concentration or emission rate measurements are
directly representative of the HCl emissions or can be corrected so
as to be representative of the emissions from the affected facility.
For CEMS sampling at a single point, a location that has been shown
to be free of HCl (or sulfur dioxide (SO2))
stratification is recommended. If you fail the RA requirements in
this specification due to the measurement location and a
satisfactory correction technique cannot be established, the
Administrator may require the CEMS to be relocated.
8.3 Measurement Location. The measurement location should be (1)
at least two equivalent diameters downstream of the nearest control
device, point of pollution generation or other point at which a
change of pollutant concentration may occur; and (2)
[[Page 27700]]
at least half an equivalent diameter upstream from the effluent
exhaust. The equivalent duct diameter is calculated according to
Method 1 in Appendix A-1 to this part.
8.3.1 Single point sample gas extraction should be (1) no less
than 1.0 meter (3.3 ft.) from the stack or duct wall or (2) within
the centroidal velocity traverse area of the stack or duct cross
section.
8.3.2 Path-integrated measurements must (1) be conducted totally
within the inner area bounded by a line 1.0 meter (3.3 ft.) from the
stack or duct wall, or (2) have at least 70 percent of the path
within the inner 50 percent of the stack or duct cross-sectional
area, or (3) be located over any part of the centroidal area.
8.4 CEMS and Data Recorder Scale Check. After CEMS installation,
we recommend you check the CE as described in section 11.7 to verify
that the instrument is functioning properly. Record and document the
measurement range of the HCl CEMS. The CEMS operating range (zero
through CRAS) and the range of the data collection device must
encompass the applicable emission limit and all expected HCl
concentrations. The CEMS and data collection device output range
must include zero and the CRAS value.
9.0 Quality Control. [Reserved]
10.0 Calibration and Standardization. [Reserved]
11.0 Performance Specification Test Procedure.
After completing the CEMS installation, setup and calibration,
you must complete the performance specification test procedures in
this section. You must perform the following procedures and meet the
performance requirements for the initial demonstration of your HCl
CEMS:
a. Interference Test;
b. Beam Intensity Test (IP-CEMS only);
c. Stack Temperature Verification (IP-CEMS only);
d. Stack Pressure Verification (IP-CEMS only);
e. Level of Detection (LOD) Determination;
f. Response Time (RT) Test;
g. Calibration Error (CE) Test;
h. Calibration Drift (CD) Test; and
i. Relative Accuracy (RA) Test:
Comparison with RM
Stratification Test
Optional Dynamic Spiking (DS) Test.
11.1 Interference Test
11.1.1 You must conduct the interference test of your
measurement system prior to its initial use in the field to verify
that the candidate system measures HCl accurately in the presence of
common interferences in emission matrices.
11.1.2 Your interference test may be conducted in either a
controlled environment or on-site during initial setup and
qualification of your CEMS.
11.1.3 If you have multiple measurement systems with components
of the same make and model numbers, you need only perform this
interference check on one system and you may also rely on an
interference test conducted by the manufacturer on a system having
components of the same make and model(s) of the system that you use.
11.1.4 Perform the interference check with an HCl concentration
between 10 and 40 percent of the span value anticipated for your
source CEMS application. Alternatively, successfully conducting the
interference test at the relevant regulatory standard may be used to
demonstrate performance.
11.1.5 Introduce the interference test gases listed in Table 1
in section 17.0 into the measurement system separately or in any
combination.
11.1.5.1 For extractive CEMS, the interference test gases must
be introduced into the sampling system at the probe such that the
interference gas mixtures pass through all filters, scrubbers,
conditioners, and other components as would be configured at a
typical field site.
11.1.5.2 For IP-CEMS, the interference test gases may be added
with the HCl in a calibration cell or separately in a temperature-
controlled cell with an effective path length in the optical CEMS
path representative of the required method detection level. Test gas
and interference gas is added to the cell at a concentration that is
equivalent to the effective stack concentration corrected for
pressure, temperature and the nominal stack sampling path length of
the CEMS.
11.1.6 The interference test must be performed by combining an
HCl gas with each interference test gas (or gas mixture). You must
measure the baseline HCl response, followed by the response after
adding the interference test gas(es) at a constant HCl
concentration. Your baseline HCl measurement must agree within three
percent of the theoretical HCl concentration. You must perform each
interference gas injection and evaluation in triplicate, and assess
the combined interference of all of the gases in Table 1.
(Note: The baseline HCl injection may include interference gases at
concentrations typical of ambient air (e.g., 21 percent
O2, 400 parts per million (ppm) CO2, 2 percent
H2O), but these concentrations must be brought to the
concentrations listed in Table 1 when their interference effects are
being evaluated.)
11.1.7 You must document the quality and quantity of the gas
volume/rate, temperature, and pressure used to conduct the
interference test to be able to establish the error of blending the
HCl and interference gases while maintaining a known HCl
concentration. A gas blending system or manifold may be used.
11.1.8 The duration of each interference test should be
sufficient to ensure the HCl measurement system surfaces are
conditioned and a stable measurement is obtained.
11.1.9 Measure the HCl response of the analyzer to these gases
in ppm. Record the responses and determine the overall interference
response using Table 2 in section 17.0.
11.1.10 For each interference gas (or mixture), calculate the
mean difference ([Delta]MCavg) between the measurement
system responses with and without the interference test gas(es)
using Equation 1 in section 12.0. Summarize the results following
the format contained in Table 2 in section 17.0.
11.1.11 Calculate the total percent interference (I) for the gas
runs using Equation 2 in section 12.0. The combined interference
response for the analyzer that was used for the test must not be
greater than 3.0 percent of the equivalent HCl
concentration used for the interference test.
11.2 Beam Intensity Test for IP-CEMS
11.2.1 For IP-CEMS, you must establish the beam intensity
attenuation tolerance of your system and demonstrate that the HCl
span response is independent of the beam intensity in the absence of
HCl.
11.2.2 Insert one or more neutral density filter(s) or otherwise
attenuate the beam intensity (e.g., 90 percent of the beam
intensity).
11.2.3 Perform a high-level calibration check.
11.2.4 Record and report the attenuated beam intensity,
calibration gas concentration measured by the CEMS and the percent
difference between the measured calibration gas concentration at
full beam intensity and the measured concentration with attenuated
beam intensity. The percent difference during the attenuated beam
intensity calibration check for the light source and detector used
in the IP-CEMS must not be more than 3.0 percent of the
measured calibration concentration used for the test.
11.2.5 In the future, you may not operate your IP-CEMS at a beam
intensity lower than that established during this test. However, you
may repeat the test to establish a lower beam intensity cut point.
11.3 Temperature Measurement Verification Procedure for IP-CEMS
11.3.1 Any measurement instrument or device that is used to
conduct ongoing verification of temperature measurement must have an
accuracy that is traceable to NIST.
11.3.2 You must perform a temperature verification test on-site
as part of the initial installation and verification procedures.
11.3.3 Comparison to Calibrated Temperature Measurement Device.
11.3.3.1 Place the sensor of a calibrated temperature
measurement device adjacent to the sensor used to measure stack
temperature for your HCl CEMS. The calibrated temperature
measurement device must satisfy the accuracy requirements specified
in Table 3 of this PS. The calibrated temperature measurement device
must also have a range equal to or greater than the range of your
HCl CEMS temperature monitor.
11.3.3.2 Allow sufficient time for the response of the
calibrated temperature measurement device to reach equilibrium. With
the process or control device operating under normal conditions
concurrently, record the temperatures measured by your HCl CEMS
system (Mt) and the calibrated measurement device
(Vt). You must meet the accuracy requirements described
in section 13.5.4 of this PS.
11.3.3.3 If your HCl CEMS temperature monitor does not satisfy
the accuracy requirement of this PS, check all system components and
take any corrective action that is necessary to achieve the required
minimum accuracy. Repeat this validation check procedure until the
accuracy requirement of this specification is satisfied.
11.4 Pressure Measurement Verification Test for IP-CEMS
[[Page 27701]]
11.4.1 For stack pressure verification, you should select a
gauge or monitor that conforms to the design requirements of ASME
B40.100-2010, ``Pressure Gauges and Gauge Attachments''
(incorporated by reference--see Sec. 60.17).
11.4.2 As an alternative for a calibrated pressure measurement
device with NIST traceable accuracy, you may use a mercury-in-glass
or water-in-glass U-tube manometer to validate your pressure
measurement equipment.
11.4.3 Allow sufficient time for the response of the calibrated
pressure measurement device to reach equilibrium. With the process
or control device operating under normal conditions, concurrently
record the pressures measured by your HCl CEMS system
(MP) and the calibrated measurement device
(Vp). You must meet the accuracy requirements described
in section 13.5.5 of this PS.
11.4.4 If your HCl CEMS pressure monitor does not satisfy the
accuracy requirement of this PS, check all system components and
take any corrective action that is necessary to achieve the required
minimum accuracy. Repeat this validation check procedure until the
accuracy requirement of this specification is satisfied.
11.5 Level of Detection (LOD) Determination
11.5.1 You must determine the minimum amount of HCl that can be
detected above the background in a representative gas matrix.
11.5.2 You may perform the LOD determination as part of the
interference test in section 11.1, in either a controlled
environment or on-site during initial setup and qualification of
your CEMS.
11.5.2.1 For extractive CEMS, spike the HCl and interferents
into the CEMS at the probe prior to all filters and sample
conditioning elements.
11.5.2.2 For IP-CEMS, spike the mixture described in section
11.1.4 into the system calibration cell.
11.5.3 The challenge standard mixture used to determine LOD must
include HCl at a concentration no greater than three times the
estimated LOD and must include the interferences listed in Table 1
of this PS.
11.5.4 Collect seven consecutive measurements separated by twice
the response time.
11.5.5 Calculate the standard deviation of the measured values
and define the LOD as three times the standard deviation of these
measurements.
11.5.5.1 The LOD for extractive units must be determined and
reported in ppmv.
11.5.5.2 The LOD for IP units must be determined and reported on
a ppm-meter basis and the site- or installation-specific LOD must be
calculated based on the actual measurement path length and gas
density of the specific site installation in ppmv.
11.5.6 If you choose to perform the LOD determination test in a
controlled environment, you must verify the LOD during the initial
field certification test using the DS test procedure in Appendix A
of this PS.
11.5.6.1 You must make three independent DS measurements at no
more than five times the LOD for the detection level verification.
11.5.6.2 If your system limitation verification does not
demonstrate the ability to distinguish the spike concentration from
the background, you must increase the spike concentration
incrementally until you establish a field verified detection level
where the HCl measurement is a minimum of three times the noise for
zero HCl concentration. The field verified detection level replaces
the controlled environment LOD and becomes the site- or
installation-specific LOD.
11.6 Response Time Determination
11.6.1 If your HCl CEMS extracts gas from stack emissions you
must determine the average upscale and downscale RTs from three
repetitions of each test. You will report the greater of the average
upscale or average downscale RTs as the RT for the system.
11.6.2 Start the upscale RT determination by injecting zero gas
into the measurement system at the extractive probe tip or IP
calibration cell inlet. You may use humidified zero gas.
11.6.3 When the system output has stabilized (no change greater
than 1 percent of full scale for 30 sec), record the response in
ppmv and introduce an upscale reference gas.
11.6.4 Take repetitive measurements until you obtain a stable
value at 95 percent or greater than the expected calibration gas
response. You may use humidified calibration gas.
11.6.5 Record the time (upscale RT) required to reach 95 percent
of the final stable value.
11.6.6 Next, reintroduce the zero gas and record the time
required to reach five percent of the zero gas reading. This time is
the downscale RT.
(Note: For CEMS that perform a series of operations (purge, blow
back, sample integration, analyze, etc.), you must start adding
calibration gases immediately after these procedures are complete.)
11.6.7 Repeat the entire procedure three times and determine the
mean upscale and downscale RTs. The slower or longer of the two
means is the system RT.
11.7 Calibration Error (CE) Test. The percent CE is the mean
difference between the HCl calibration gas value and the CEMS
response at each calibration point expressed as a percentage of the
span. The CE must be less than five percent.
11.7.1 Extractive CEMS CE check.
11.7.1.1 Sequentially introduce calibration gas to the CEMS
probe, before the sample conditioning and filtration system.
11.7.1.2 Measure three upscale HCl gas concentrations in the
ranges shown in Table 4 of this PS.
11.7.1.3 Introduce the gases into the sampling probe with
sufficient flow rate to replace the entire source gas sample.
11.7.1.4 Continue to add the standard gas until the response is
stable as evidenced when the difference between two consecutive
measurements is less than the LOD or within five percent of each
other.
11.7.1.5 Make triplicate measurements for each gas standard.
Introduce different calibration concentrations in any order but do
not introduce the same gas concentration twice in succession.
Conduct independent measurements three times for each concentration,
for a total of nine measurements.
11.7.1.6 At each reference gas concentration, determine the
average of the three CEMS responses
[GRAPHIC] [TIFF OMITTED] TP14MY14.038
Calculate the CE using Equation 3 in section 12.0.
11.7.1.7 If you desire to determine the system RT during this
test, you may inject zero gas immediately followed by the high-level
standard.
11.7.1.8 For non-dilution systems, you may adjust the system to
maintain the correct flow rate at the analyzer during the test, but
you may not make adjustments for any other purpose. For dilution
systems, you must operate the measurement system at the appropriate
dilution ratio during all system CE checks, and you may make only
the adjustments necessary to maintain the proper ratio.
11.7.2 IP-CEMS CE check
11.7.2.1 Conduct a 3-point system CE test by sequential addition
of known concentrations of HCl standard into a calibration cell of
known volume, temperature, pressure and path length.
(Note: The optical path used for IP-CEMS calibration error checks
must include the native measurement path. You must also collect
native stack concentration before and after each HCl standard
measurement. Bracketing HCl standard measurements with native stack
measurements may be used in the calculations to correct the upscale
measurements for stack gas HCl concentration changes.)
11.7.2.2 Introduce HCl standards into your calibration cell in a
range of concentrations that produce responses equivalent to the
source concentrations shown in Table 4 for your path length.
11.7.2.3 Introduce the low-, mid-, and high-level calibration
standards in any order. Make three independent measurements of each
concentration. Introduce different calibration concentrations in any
order but do not introduce the same gas concentration twice in
succession.
11.7.2.4 You must calculate the equivalent concentration
(Ci,eff) of the HCl calibration gas equivalent to the
stack concentration by correcting for calibration cell temperature,
pressure, path length, line
[[Page 27702]]
strength factor (LSM) and, if necessary, the native source gas HCl
concentration using equations 4, 5 and 6 in section 12.0.
11.7.2.5 You may use the LSM provided by your instrument
manufacturer or determine an instrument-specific LSM as a function
of temperature using a heated gas cell and effective gas
concentrations (Ci,eff) between 50 and 150 percent of the
emission limit.
11.7.2.6 At each gas concentration, determine the average of the
three independent CEMS measurement responses corrected for stack
concentration, and the average response during zero gas injections
(background or native stack gas measurement). Calculate the CE using
Equation 6 in section 12.0.
11.7.3 You may use Figure 1 to record and report your CE test
results.
11.7.4 If the CE specification is not met for all three standard
concentrations, take corrective action and repeat the test until an
acceptable 3-point CE test is achieved.
11.8 Seven-Day Calibration Drift (CD) Test
11.8.1 The CD Test Period. Prior to the start of the RA tests,
you must perform a CD test. The purpose of the CD measurement is to
verify the ability of the CEMS to maintain calibration for each of
seven, 24-hour periods.
11.8.2 The CD tests must be performed using the zero and either
mid-level or high-level calibration standards as defined in Table 4.
11.8.3 Conduct the CD test during normal facility operations
following the procedures in section 11.7 of this PS.
11.8.4 If periodic automatic or manual adjustments are made to
the CEMS zero and upscale response factor settings, conduct the CD
test immediately before these adjustments.
(Note: Automatic signal or mathematical processing of all
measurement data to determine emission results may be performed
throughout the entire CD process.)
11.8.5 Determine the magnitude of the CD at 24-hour intervals,
for seven consecutive unit operating days. The seven consecutive
unit operating days need not be seven consecutive calendar days. You
may use Figure 2 to record and report the results of your CD test.
11.8.6 Record the average CEMS response for zero gas and mid- or
high-level calibration gas.
11.8.6.1 For extractive CEMS, calculate the CD using Equation 3
in section 12. Report the absolute value of the differences as a
percentage of the span value.
11.8.6.2 For IP-CEMS, you may exclude the in stack measurement
path when determining zero gas concentration. Calculate the CD using
equations in section 12.4.
11.8.7 You must record the average CEMS response for each
reference gas and calculate the mid- or high-level CD using Equation
6 in section 12.0. Calculate the zero drift value using Equation 7.
11.8.8 The zero-level and high-level drift for each day must be
less than five percent of the span value. You must pass each day's
drift checks for seven days to meet this requirement. Each zero- and
high-level drift check must be recorded and reported for the seven-
day drift check tests.
11.9 Relative Accuracy (RA) Test
11.9.1 Unless otherwise specified in an applicable subpart of
the regulations, use Method 26A in 40 CFR part 60 Appendix A-8,
Method 320 and Method 321, both found in 40 CFR part 63 Appendix A,
or ASTM D6348-12 including mandatory annexes, as the acceptable
reference methods for HCl measurement. Other RMs for moisture,
O2, etc., may be necessary. Conduct the RM tests in such
a way that they will yield results representative of the emissions
from the source and can be compared to the CEMS data.
11.9.2 Conduct the diluent (if applicable), moisture (if
needed), and pollutant measurements simultaneously. However, diluent
and moisture measurements that are taken within an hour of the
pollutant measurements may be used to calculate dry pollutant
concentration and emission rates.
11.9.3 Stratification Test. A stratification test must be
conducted during normal facility operating conditions. The purpose
of this test is to verify that excess stratification of the target
pollutant does not render the sampling point of the CEMS non-
representative. You must traverse as required in this section while
taking reference method samples used for the RA testing.
11.9.3.1 Perform a stratification test at each test site to
determine the appropriate number of sample traverse points. If
testing for multiple pollutants or diluents at the same site, a
stratification test using only one pollutant or diluent satisfies
this requirement. A stratification test is not required for small
stacks that are less than four inches in diameter. To test for
stratification, use a probe of appropriate length to measure the HCl
concentration or an alternative analyte, as described in this
section, at 12 traverse points located according to Table 1-1 or
Table 1-2 of Method 1 in Appendix A-1 to 40 CFR part 60, as
appropriate.
11.9.3.2 You may substitute a stratification test for
SO2 for the HCl stratification test if the HCl
concentration is less than ten times the LOD of your HCl CEMS. If
you select this option, you must follow the test procedures in
Method 6C of Appendix A-4 to 40 CFR part 60.
11.9.3.3 You may substitute a stratification test for
CO2, CO or nitrogen oxides (NOX) if you
anticipate the concentration of both SO2 and HCl are less
than ten times the associated LOD for the CEMS instrument.
11.9.3.4 Calculate the mean measured concentration for all
sampling points (MNavg).
11.9.3.5 Calculate the percent stratification (St) of
each traverse point using Equation 8 in section 12.0.
11.9.3.5.1 If the concentration at any traverse point differs
from the mean concentration for all traverse points by no more than:
(a) 5.0 percent of the mean concentration or (b) 0.5 ppm (whichever is less restrictive), the gas stream is
considered unstratified and you may perform a single point RA test.
11.9.3.5.2 If the 5.0 percent or 0.5 ppm criterion is not met,
but the concentration at any traverse point differs from the mean
concentration for all traverse points by no more than: (a) 10.0 percent of the mean or (b) 1.0 ppm (whichever
is less restrictive), the gas stream is considered to be minimally
stratified, and you may take RA samples from three points. Space the
three points at 16.7, 50.0, and 83.3 percent of the measurement
traverse line.
11.9.3.5.3 If the traverse point differs from the mean
concentration by more than 10 percent, the gas stream is considered
stratified and you must conduct a full traversing RA test following
tables 1-1 and 1-2 of Method 1 in Appendix A-1 to 40 CFR part 60.
11.9.3.6 Conduct all necessary RM tests within 3 cm (1.2 in.) of
the traverse points, but no closer than 3 cm (1.2 in.) to the stack
or duct wall.
11.9.3.7 In order to correlate the CEMS and RM data properly,
record the beginning and end of each RM run (including the exact
time of day) with the permanent record of CEMS output.
11.9.4 Conduct the RA test using an RM.
11.9.4.1 You must conduct RA tests at the affected facility
during process operating conditions representing average production
and full control operation at the source, or as specified in an
applicable subpart.
11.9.4.2 Conduct a minimum of nine sets of all necessary RM test
runs.
11.9.4.3 If HCl CEMS measurements are less than or equal to 20
percent of the applicable standard, you must perform a DS
verification test during CEMS installation and performance tests
following the procedures in Appendix A of this PS.
11.9.4.4 When Method 26A is used as the RM, you must conduct the
RM test runs with paired or duplicate sampling systems and use the
average of the HCl concentrations measured by the two trains. You
must sample sufficient gas to reach three times your method
detection limit for Method 26A in 40 CFR part 60, Appendix A-8, or
for a minimum of one hour, whichever is less.
11.9.4.5 Identify outliers in the paired Method 26A data by
calculating the relative difference (RD) for the paired RM tests.
Data that do not meet the RD criteria may not be used in the
calculation of RA. The primary reason for performing paired RM
sampling is to ensure the quality of the RM data. Determine the RD
for paired data points using Equation 9 in section 12.0.
11.9.4.6 The minimum performance criteria for RM paired HCl data
is an RD for any data pair of <=10 percent when the mean HCl
concentration is greater than 50 percent of the applicable emission
limit expressed as an equivalent concentration. If the mean HCl
concentration is less than or equal to 50 percent of the applicable
emission limit expressed as an equivalent concentration, the RD must
be <=20 percent. Pairs of RM data exceeding these RD criteria must
be eliminated from the data set used to develop the HCl CEMS RA
assessment.
(Note: More than nine sets of RM tests may be performed. If this
option is chosen, a maximum of three sets of the test results may be
rejected when the HCl concentration is greater than 50 percent of
the applicable standard; a maximum of six sets of test
[[Page 27703]]
results may be rejected when the HCl concentration is less than 50
percent of the applicable standard so long as the total number of
test results used to determine the RA is greater than or equal to
nine. However, all data must be reported, including the rejected
data.)
11.9.5 When Method 320 and Method 321, both found in 40 CFR part
63 Appendix A, or ASTM D6348-12, are used, you must collect gas
samples that are at stack conditions (hot and wet) and you must
traverse as required in section 11.9.3.
11.9.6 Analyze the results from the RM test runs using equations
in section 12.7 (equations 10-15). Calculate and report the RA
between the HCl CEMS results and the RM.
11.9.7 As an option, in addition to performing a RATA with a
reference method, you may perform a DS test verification during CEMS
installation and performance tests following the procedures in
Appendix A of this PS. If the HCl CEMS passes the DS test
verification, you may use DS as an alternative to selected quarterly
RATA tests as specified in 40 CFR part 60 Appendix F requirements
for ongoing quality assessment of the HCl CEMS.
11.10 Reporting
11.10.1 For systems that use a gas blender and/or liquid
evaporative calibrator to deliver HCl gas standards, record and
report supporting data for these devices, including liquid feed
calibrations, liquid standard(s) concentration, feed rate and gas
flow calibrations for all diluent and HCl gas flows. All
calibrations must include a stated uncertainty, and the combined
uncertainty of the delivered gas concentration must be calculated
and reported.
11.10.2 Record and summarize in tabular form the results of the
CD test, the linearity tests, the RT test, CE test, RA test, and
optional spike recovery procedure, as appropriate. Include all data
sheets, calculations, CEMS data records (i.e., charts, records of
CEMS responses), and cylinder gas or other reference material
certifications necessary to confirm that the performance of the CEMS
met the performance specifications.
11.10.3 Record and report supporting dilution system data
including standard cylinder gas flow, total gas flow, and the
results of the test measurements.
11.10.4 Record and report the LOD and system limitation
verification in ppmv for the HCl CEMS as installed.
12.0 Calculations and Data Analysis.
12.1 Nomenclature
Ci = Actual HCl calibration gas concentration used for
test i (ppmv);
Ci,eff = Equivalent concentration of the reference value,
Ci, at the specified conditions;
CC = Confidence coefficient;
CDextractive = Calibration drift for extractive CEMS
(percent);
CDIP = Calibration drift for IP-CEMS (percent);
CD0 = The calibration drift at zero HCl concentrations
for an IP-CEMS;
CEextractive = Calibration error for extractive CEMS
(percent);
CEIP = Calibration error for IP-CEMS (percent);
davg = Mean difference between CEMS response and the
reference gas (ppmv);
di = Difference of CEMS response and the RM value (ppmv);
I = Total interference from major matrix stack gases, percent;
LSM = Line strength factor for IP-CEMS, measurements, temperature
dependent derivation from the HITRAN database;
[Delta]MCavg = Average of the 3 absolute values of the
difference between the measured HCl calibration gas concentrations
with and without interference from selected stack gases (ppmv);
MCi = Measured HCl calibration gas concentration i
(ppmv);
MCint = Measured HCl concentration of the HCl calibration
gas plus the individual or combined interference gases (ppmv);
MNavg = Average concentration at all sampling points
(ppmv);
MNb = Measured native concentration bracketing
calibration spike measurements;
MNi = Measured native concentration for test or run i
(ppmv);
n = Number of measurements in an average value;
PLCell = Path length of IP-CEMS calibration cell;
PLStack = Path length of IP-CEMS stack optical path;
Ra = HCl concentration measured by the first of two RM
pairs (ppmv);
Rb = HCl concentration measured by the second of two RM
pairs (ppmv);
RA = Relative accuracy of CEMS compared to a RM (percent);
RD = Relative difference between paired RM trains (percent);
RMi = RM concentration for test run I;
RMavg = Mean measured RM value or the mean dynamic spike
concentration (ppmv);
S = Span of the instrument (ppmv);
Sd = Standard deviation of the differences;
St = Stratification (percent);
t0.975 = One-sided t-value obtained from Table 5 for n-1
measurements;
Treference = Temperature of the calibration cell for IP-
CEMS (degrees Kelvin);
Tstack = Temperature of the stack at the monitoring
location for IP-CEM (degrees Kelvin).
12.2 Calculate the difference between the measured HCl
concentration with and without interferents for each interference
gas (or mixture) for your CEMS as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.014
Calculate the total percent interference as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.015
12.3 Calculate the calibration error or calibration drift at
concentration i for an extractive CEMS as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.016
12.4 Calculate the calibration error or calibration drift at
concentration i for IP-CEMS that use a calibration cell as follows:
12.4.1 Calculate the equivalent concentration Ci,eff
using Equation 4:
[[Page 27704]]
[GRAPHIC] [TIFF OMITTED] TP14MY14.017
12.4.2 Calculate the average native concentration before and
after a calibration check measurement as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.018
12.4.3 Calculate the calibration error or calibration drift at
concentration i for an IP-CEMS as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.019
12.4.4 Calculate the calibration drift at zero HCl
concentrations for an IP-CEMS as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.020
12.5 Calculate the percent stratification at each traverse point
as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.021
12.6 Calculate the relative difference between paired RM
sampling train results as:
[GRAPHIC] [TIFF OMITTED] TP14MY14.022
12.7 Calculate the relative accuracy using RM and CEMS Data.
12.7.1 Determine the HCl CEMS final integrated minute average
pollutant concentration or emission rate for each RM test period.
Consider system response time, if important, and confirm that the
results have been corrected to the same moisture, temperature and
diluent concentration basis.
12.7.2 When Method 26A, found in 40 CFR part 60 Appendix A-8, is
used as the RM, compare each CEMS integrated average value against
the corresponding average of the paired RM values.
12.7.3 If the RM is Method 320 or Method 321, found in 40 CFR
part 63 Appendix A, or ASTM D6348-12, make a direct comparison of
the average RM results and CEMS average value for identical test
periods.
12.7.4 Calculate the arithmetic difference of the RA
measurements to the CEMS one-minute average results using Equation
10.
[GRAPHIC] [TIFF OMITTED] TP14MY14.023
12.7.5 Calculate the standard deviation of the differences (Sd)
of the HCl CEMS measured and RM results using Equation 11.
[GRAPHIC] [TIFF OMITTED] TP14MY14.024
[[Page 27705]]
12.7.6 Calculate the confidence coefficient (CC) for the
relative accuracy tests using Equation 12.
[GRAPHIC] [TIFF OMITTED] TP14MY14.025
12.7.7 Calculate the mean difference (davg) between the RM and
CEMS values in the units of ppmv or the emission standard using
Equation 13.
[GRAPHIC] [TIFF OMITTED] TP14MY14.026
12.7.8 Calculate the average RM value using Equation 14.
[GRAPHIC] [TIFF OMITTED] TP14MY14.027
12.7.9 Calculate RA for the HCl CEMS using Equation 15.
[GRAPHIC] [TIFF OMITTED] TP14MY14.028
13.0 Method Performance.
13.1 Level of Detection. You may not use an HCl CEMS whose LOD
is greater than 20 percent of the regulatory limit or other action
level for the intended use of the data. An LOD less than or equal to
20 percent of the standard should result in 95 percent confidence
level or better for measurements at the level of the standard.
13.2 Calibration Drift. The calibration drift for the HCl CEMS
must not drift or deviate from the reference gas value by more than
five percent of the span value for seven consecutive days.
13.3 Calibration Error Check (linear or quadratic)
13.3.1 The calibration intercept must be equal to or less than
15 percent of the system span.
13.3.2 The mean percent difference between the reference gas
value and the CEMS measured concentration at each of the three
points (Eq.7) must be less than five percent of span.
13.4 Relative Accuracy Check--Reference Method. The RA of the
CEMS compared to a RM in the units of the HCl concentration must be
less than or equal to 20 percent of the RM when RMavg is used in the
denominator of Equation 14. In cases where the average emission
level for the test is less than 50 percent of the applicable
standard, substitute the equivalent emission standard value in ppmvw
in the denominator of Equation 14 in place of RMavg, and this
alternative calculated RA must be less than or equal to 15 percent
of the RM.
13.5 Response Time.
13.5.1 The RT to a measurable change in concentration must be
less than or equal to 15 minutes.
13.5.2 Interference Check. The combined interference response
for the HCl CEMS that was used for the test must not be greater than
3.0 percent of the equivalent HCl concentration used for
the interference test.
13.5.3 Integrated Path Beam Intensity. The percent difference
during attenuated light calibration check for the light source and
detector used in an IP-CEMS must not be more than 3.0
percent of the known measured concentration without attenuation used
for the test.
13.5.4 Your temperature monitor satisfies the accuracy required
if the absolute relative difference between Mt and
Vt is <= one percent or if the absolute difference
between measured value of stack temperature (Mt) and the
value of calibrated temperature reference device (Vt) is
<=2.8 [deg]C (5.0 [deg]F), whichever is greater.
13.5.5 Your pressure monitor satisfies the accuracy required if
the absolute relative difference between MP and the value
of calibrated pressure reference device (VP) is <= five
percent or if the absolute difference between the measured value of
stack pressure (Mp and VP) is <=0.12
kilopascals (0.5 inches of water column), whichever is greater.
14.0 Pollution Prevention. [Reserved]
15.0 Waste Management. [Reserved]
16.0 References.
1. Method 318, 40 CFR, part 63, Appendix A (Draft), ``Measurement of
Gaseous Formaldehyde, Phenol and Methanol Emissions by FTIR
Spectroscopy,'' EPA Contract No. 68D20163, Work Assignment 2-18,
February, 1995.
2. ``EPA Protocol for the Use of Extractive Fourier Transform
Infrared (FTIR) Spectrometry in Analyses of Gaseous Emissions from
Stationary Industrial Sources,'' February, 1995.
3. ``Measurement of Gaseous Organic and Inorganic Emissions by
Extractive FTIR Spectroscopy,'' EPA Contract No. 68-D2-0165, Work
Assignment 3-08.
4. ``Method 301--Field Validation of Pollutant Measurement Methods
from Various Waste Media,'' 40 CFR part 63, Appendix A.
5. EPA Traceability Protocol for Assay and Certification of Gaseous
Calibration Standards 2012. See www.epa.gov/ttn/emc.
17.0 Tables, Diagrams, Flowcharts, and Validation Data.
Table 1--Interference Check Gas Concentrations
------------------------------------------------------------------------
Approximate concentration
Potential interferent gas \1\ (balance N[ihel2])
------------------------------------------------------------------------
CO[ihel2]................................. 15% 1%
CO[ihel2].\2\
CO........................................ 100 20 ppm.
CH[ihel2]O................................ 20 ppm.
CH[ihel4]................................. 100 20 ppm.
NH[ihel3]................................. 10 ppm (extractive CEMS
only).
NO[ihel2]................................. 250 50 ppm.
SO[ihel2]................................. 200 20 ppm.
O[ihel2].................................. 3% 1%
O[ihel2].\2\
H[ihel2]O................................. 10% 1%
H[ihel2]O.\2\
N[ihel2].................................. Balance.\2\
------------------------------------------------------------------------
\1\ Any of these specific gases can be tested at a lower level if the
manufacturer has provided reliable means for limiting or scrubbing
that gas to a specified level.
\2\ Gases for short path IP cell interference tests added at relative
concentration ratios indicated in the table.
[[Page 27706]]
Table 2--Example Interference Test Data Sheet
Date of Test:----------------------------------------------------------
Analyzer Type:---------------------------------------------------------
Model No.:-------------------------------------------------------------
Serial No.:------------------------------------------------------------
Span:------------------------------------------------------------------
Calibration Range Above Span:------------------------------------------
Test Organization:-----------------------------------------------------
Test Personnel:--------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
HCl concentration
Interference gas or HCl concentration (ppmv) w/ Absolute difference Average absolute
gas combination (ppmv) interference (ppmv) difference (ppmv)
----------------------------------------------------------------------------------------------------------------
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Sum of Responses
----------------------------------------------------------------------------------------------------------------
% of Calibration Span
----------------------------------------------------------------------------------------------------------------
Table 3--Design Standards for Temperature Sensors
------------------------------------------------------------------------
You can use the following design
If the sensor is a . . . standards as guidance in
selecting a sensor for your CPMS
------------------------------------------------------------------------
1. Thermocouple...................... a. ASTM E235-88 (1996),
``Specification for
Thermocouples, Sheathed, Type K,
for Nuclear or Other High-
Reliability Applications.''
[[Page 27707]]
b. ASTM E585/E585M-04,
``Specification for Compacted
Mineral-Insulated, Metal-
Sheathed, Base Metal
Thermocouple Cable.''
c. ASTM E608/E608M-06,
``Specification for Mineral-
Insulated, Metal-Sheathed Base
Metal Thermocouples.''
d. ASTM E696-07, ``Specification
for Tungsten-Rhenium Alloy
Thermocouple Wire.''
e. ASTM E1129/E1129M-98 (2002),
``Standard Specification for
Thermocouple Connectors.''
f. ASTM E1159-98 (2003),
``Specification for Thermocouple
Materials, Platinum-Rhodium
Alloys, and Platinum.''
g. ISA-MC96.1-1982, ``Temperature
Measurement Thermocouples.''
------------------------------------------------------------------------
2. Resistance temperature detector... ASTM E1137/E1137M-04, ``Standard
Specification for Industrial
Platinum Resistance
Thermometers.''
------------------------------------------------------------------------
Table 4--Performance Specification Test Calibration Gas Ranges
----------------------------------------------------------------------------------------------------------------
HCl calibration material concentrations \a\
------------------------------------------------
Test Units High Section
Zero Low level Mid level level
----------------------------------------------------------------------------------------------------------------
Calibration Drift............... % of Span.......... 2.0 percent accuracy or calculate the flow using a stable
tracer gas included in your spike gas standard.
8.2.4.2 If you use flow measurements to determine the spike
dilution, then use equation A1 in section 11 of this appendix to
calculate the DF. Total probe flow measurement requires measurement
of HCl spike flow (Qspike) and total flow through the CEM
sampling system (Qprobe).
8.2.4.3 If your CEMS is capable of measuring an independent
stable tracer gas, you may use a spike gas that includes the tracer
to determine the DF using equation A2 in section 11 of this
appendix.
8.2.5 Begin by collecting unspiked sample measurements. You must
use the average of two unspiked sample measurements as your pre-
spike background.
(Note: Measurements should agree within five percent or three
times the level of detection to avoid biasing the spike recovery
results.)
8.2.5.1 Introduce the HCl gas spike into the permanent CEMS
probe, upstream of the particulate filter or sample conditioning
system and as close to the sampling inlet as practical.
8.2.5.2 Maintain the HCl gas spike for at least twice the
response time of your CEMS or until the consecutive measurements
agree within five percent. Collect two independent measurements of
the native plus spiked HCl concentration.
8.2.5.3 Stop the flow of spike gas for at least twice the
response time of your CEMS or until the consecutive measurements
agree within five percent. Collect two independent measurements of
the native HCl concentration.
8.2.6 Repeat the collection of sample measurements in section
8.2.5 until you have data for each spike concentration for a total
of nine sets of data including a final set of unspiked sample
measurements according to section 8.2.5.
8.2.7 Calculate the percent recovery for extractive CEMS as
described in section 11.2 of this appendix.
8.2.8 If the spikes persistently show poor recovery
repeatability, or if the recoveries are not within the range
specified in section 12 of this appendix, you must take corrective
action and repeat the dynamic spiking accuracy procedure.
8.3 Dynamic Spiking Procedure for IP-CEMS.
8.3.1 For IP-CEMS, you must spike a known quantity of
calibration gas into a calibration cell that is in the optical path
used to make CEMS source measurements.
8.3.2 Use calibration gas at a concentration that produces a
signal equivalent to the ranges specified in Table 4 of PS-18.
8.3.3 Introduce zero gas into a permanently mounted calibration
cell located in the optical measurement path of the instrument.
Continue to flush the zero gas into the cell for at least the
response time of your CEMS or until two consecutive measurements
taken are within five percent, then collect two independent
measurements. Introduce spike gas into the same calibration cell.
Continue to flush the spike gas into the cell for at least the
response time of your CEMS or until two consecutive measurements
taken are within five percent. Then collect two independent
measurements.
8.3.4 Repeat the collection of sample spike and native HCl
measurements in section 8.3.3 until you have data for each spike
concentration for a total of nine sets of data including a final
zero gas sample measurement. The measured concentrations must be
corrected for calibration cell and stack temperature, pressure and
stack measurement path length.
8.3.5 Calculate the percent spike recovery (%SA) for IP-CEMS, as
described in section 11.2.3.5, using the appropriate equations in
section 11.2 of this appendix.
8.3.6 If the spikes persistently show poor repeatability, or if
the recoveries are not within the range specified in section 12 of
this appendix, you must take corrective action and repeat the
dynamic spiking accuracy procedure.
A9. Quality Control. (Reserved)
A10. Calibration and Standardization. (Reserved)
A11. Calculations and Data Analysis. Calculate the spike
recoveries for each injection and its associated pair of native HCl
measurements, using equations in this section. (Note: For cases
where the emission standard is expressed in units of lb/MMBtu or
corrected to a specified O2 or CO2
concentration, an absolute accuracy specification based on a span at
stack conditions may be calculated using the average concentration
and applicable conversion factors. The appropriate procedures for
use in cases where a percent removal standard is more restrictive
than the emission standard are the same as in 40 CFR part 60 PS-2,
sections 12 and 13.)
11.1 Nomenclature
Ci = Actual HCl calibration gas concentration used for
test i (ppmv);
Ci,eff = Spike equivalent concentration of the reference
value, Ci, at the specified conditions;
Cspike gas = Actual HCl standard gas concentration spiked (e.g.,
bottle or standard gas concentration) ppmv;
Ctracer spiked = Tracer gas concentration injected with spike gas
(``standard concentration'') ppmv;
Cexpected = Expected HCl concentration response for dynamic spike;
CC = Confidence coefficient;
DF = Spiked gas dilution factor;
LSM = Line strength factor for integrated path; measurements,
temperature dependent derivation from the HITRAN database (see
http://www.cfa.harvard.edu/hitran/ for HITRAN access);
MCi = Measured HCl calibration gas concentration i
(ppmv);
MCnative = Average measured concentration of the native
HCl (ppmv);
Mnative tracer = Measured tracer gas concentration
present in native effluent gas (ppmv);
Mspiked tracer = Measured diluted tracer gas
concentration in a spiked sample (ppmv);
n = Number of measurements in an average value;
PLCell = Path length of IP-CEMS calibration cell;
PLStack = Path length of IP-CEMS stack optical path;
Qspike = Flow rate of the dynamic spike gas (Lpm);
Qprobe = Average total stack sample flow through the
system (Lpm);
S = Span;
%SA = Spike recovery accuracy (percent);
%SRavg = Mean dynamic spike recovery (percent);
%SRi = Dynamic spike recovery (percent);
Sd = Standard deviation of the differences;
t0.975 = One-sided Students t-value n-1 measurements;
Tstack = Temperature of the stack gas;
Treference = Temperature measured by the reference
temperature indicator.
11.2 Calculating Dynamic Spike Recovery for Extractive CEMS.
11.2.1 If you determine your spike dilution factor using spike
gas and stack sample flow measurements, calculate the dilution
factor for dynamic spiking accuracy tests using equation A1:
[[Page 27710]]
[GRAPHIC] [TIFF OMITTED] TP14MY14.000
11.2.2 If you determine your spike dilution factor using an
independent stable tracer gas that is not present in the native
source gas, calculate the dilution factor for dynamic spiking using
equation A2:
[GRAPHIC] [TIFF OMITTED] TP14MY14.001
11.2.3 If you determine your spike dilution factor using an
independent stable tracer that is present in the native source gas,
calculate the dilution factor for dynamic spiking using equation A3:
[GRAPHIC] [TIFF OMITTED] TP14MY14.002
11.2.3.1 Calculate the percent spike recovery (SRi)
between the CEMS results and the spike gas concentration for each
spiked sample measurement using equation A4.
[GRAPHIC] [TIFF OMITTED] TP14MY14.003
11.2.3.2 You must calculate the mean of the recovery for the
nine (or more) dynamic spikes using equation A5.
[GRAPHIC] [TIFF OMITTED] TP14MY14.004
11.2.3.3 You must calculate the standard deviation of the spike
recoveries for the nine (or more) dynamic spiking measurements to
determine CEMS accuracy using equation A6.
[GRAPHIC] [TIFF OMITTED] TP14MY14.005
11.2.3.4 Calculate the confidence coefficient (CC) for the
relative accuracy tests using equation A7.
[GRAPHIC] [TIFF OMITTED] TP14MY14.006
11.2.3.5 Calculate the percent %SA for the extractive CEMS using
equation A8.
[GRAPHIC] [TIFF OMITTED] TP14MY14.007
11.3 DS Recovery for IP-CEMS.
11.3.1 If you use an in-situ IP-CEMS and a calibration cell,
calculate and substitute the spike equivalent concentration
Ci,eff for Cspike using equation A9:
[[Page 27711]]
[GRAPHIC] [TIFF OMITTED] TP14MY14.008
11.3.2 Calculate the percent spike equivalent recovery
(%SRi) between the CEMS results and the spike equivalent
concentration for each spiked sample measurement using equation A10.
[GRAPHIC] [TIFF OMITTED] TP14MY14.009
11.3.3 Calculate the average spike recovery (SRavg)
using equation A11.
[GRAPHIC] [TIFF OMITTED] TP14MY14.010
11.3.4 Calculate the standard deviation of the spike recoveries
for the nine (or more) dynamic spiking measurements to determine
CEMS accuracy using equation A12.
[GRAPHIC] [TIFF OMITTED] TP14MY14.011
11.3.5 Calculate the confidence coefficient (CC) for the spiking
accuracy using equation A13.
[GRAPHIC] [TIFF OMITTED] TP14MY14.012
11.3.6 Calculate the relative spike recovery accuracy (%SA) for
the IP-CEMS using equation A14.
[GRAPHIC] [TIFF OMITTED] TP14MY14.013
A12. Performance Requirements DS Spike Accuracy Check.
12.1 The %SA of the average CEMS results calculated using
equation A8 for extractive CEMS or equation A14 for IP-CEMS in the
units of HCl concentration (ppm) must be less than or equal to 25
percent of (the average of) the spiked sample concentration.
A13. Tables and Figures.
Table 1--Spike Recovery Work Sheet
------------------------------------------------------------------------
------------------------------------------------------------------------
Facility name: Date: Time:
------------------------------------------------------------------------
Unit(s) tested: Test personnel:
------------------------------------------------------------------------
Analyzer make and model: ...................................
------------------------------------
Serial number: ...................................
------------------------------------
Calibration range above span: ...................................
------------------------------------------------------------------------
[[Page 27712]]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cnative Actual Values
Qspike ------------------------------------------------------------------------- SR (% spike
Qprobe (lpm) (lpm) CF\1\ Ci\2\ recovery)
Pre Post Avg (ppmv) MCss\3\ (ppmv)
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
........... ........... ........... ........... ........... ........... Average ...................
--------------------------------------------------------------------------------------------------------------------------------------------------------
........... ........... ........... ........... ........... ........... SD ...................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ CF must be >= 10 for extractive CEMS.
\2\ Ci = Actual HCl concentration of the spike gas, ppmv.
\3\ MCss = Measured HCl concentration of the spiked sample at the target level, ppmv.
0
3. Appendix F to part 60 is amended by adding Procedure 6 to read as
follows:
Appendix F to Part 60--Quality Assurance Procedures
* * * * *
Procedure 6. Quality Assurance Requirements for Gaseous Hydrogen
Chloride (HCl) Continuous Emission Monitoring Systems Used for
Compliance Determination at Stationary Sources
1.0 Applicability and Principle.
1.1 Applicability. Procedure 6 is used to evaluate the
effectiveness of quality control (QC) and quality assurance (QA)
procedures and evaluate the quality of data produced by any hydrogen
chloride (HCl) gas, CAS: 7647-01-0, continuous emission monitoring
system (CEMS) that is used for determining compliance with emission
standards for HCl on a continuous basis as specified in an
applicable permit or regulation.
1.1.1 This procedure specifies the minimum QA requirements
necessary for the control and assessment of the quality of CEMS data
submitted to the Environmental Protection Agency (EPA). Source
owners and operators responsible for one or more CEMS used for HCl
compliance monitoring must meet these minimum requirements and are
encouraged to develop and implement a more extensive QA program or
to continue such programs where they already exist.
1.1.2 Data collected as a result of QA and QC measures required
in this procedure are to be submitted to the EPA or the delegated
authority. These data are to be used by both the responsible agency
and the CEMS operator in assessing the effectiveness of the CEMS QC
and QA procedures in the maintenance of acceptable CEMS operation
and valid emission data.
1.2 Principle.
1.2.1 The QA procedures consist of two distinct and equally
important functions. One function is the assessment of the quality
of the HCl CEMS data by estimating accuracy. The other function is
the control and improvement of the quality of the CEMS data by
implementing QC policies and corrective actions. These two functions
form an iterative control loop. When the assessment function
indicates that the data quality is inadequate, the control effort
must be increased until the data quality is acceptable. In order to
provide uniformity in the assessment and reporting of data quality,
this procedure specifies the assessment procedures to evaluate
response drift and accuracy. The procedures specified are based on
Performance Specification 18 (PS-18) in appendix B of this part.
Procedure 6 also requires the analysis of reference method audit
samples, if they are available, concurrently with reference method
tests as specified in the general provisions of the applicable part.
(Note: Because the control and corrective action function
encompasses a variety of policies, specifications, standards and
corrective measures, this procedure treats QC requirements in
general terms to allow each source owner or operator to develop the
most effective and efficient QC system for their circumstances.)
2.0 Definitions.
2.1 Calibration Cell means a gas containment cell used with
cross stack or integrated path (IP) monitoring systems to perform
precision and calibration checks. The cell may be a removable sealed
cell or an evacuated and/or purged cell capable of exchanging
calibration and zero gases. When charged for calibration, the
calibration cell contains a known concentration of calibration gas.
The calibration cell is filled with zero gas or removed from the
optical path during normal stack gas measurement.
2.2 Calibration Drift (CD) means the absolute value of the
difference between the CEMS output response and an upscale reference
gas or a zero-level reference gas, expressed as a percentage of the
span value, when the CEMS is challenged after a stated period of
operation during which no unscheduled maintenance or repair took
place. A separate CD determination must be performed for pollutant
and diluent analyzers. The calibration standards must meet the
requirements of section 7.0 in PS-18 of Appendix B in this part.
2.3 Continuous Emission Monitoring System (CEMS) means the total
equipment required under the emission monitoring sections in
applicable subparts, used to sample and condition (if applicable),
to analyze, and to provide a permanent record of emissions or
process parameters.
2.4 Diluent Gas means a major gaseous constituent in a gaseous
pollutant mixture. For combustion sources, either carbon dioxide
(CO2) or oxygen (O2) or a combination of these
two gases are the major gaseous diluents of interest.
2.5 Dynamic Spiking (DS) means, for extractive CEMS, the
procedure where a known concentration of HCl gas is injected into
the sample gas stream at the probe with a known flow rate; for in-
situ IP-CEMS, it is a procedure where a known concentration of HCl
gas is spiked into a calibration cell. In both cases, the procedure
is performed to assess the accurate recovery of HCl introduced into
the measurement system in the presence of potential interference
from the flue gas sample matrix.
2.6 Liquid Evaporative Standard means a calibration standard
produced by vaporizing National Institute of Standards and Testing
(NIST) traceable liquid standards of known
[[Page 27713]]
HCl concentration and quantitatively mixing the resultant vapor with
a diluent carrier gas.
2.7 Span Value means the calibration portion of the measurement
range as established by the applicable regulatory requirement. If
the span is not specified by an applicable regulation or other
requirement, then it must be equal to an instrument value
representative of twice the emission limit.
2.8 HCl concentration values (Zero, Low-Level, Mid-Level and
High-Level Values) means the values that are defined in Table 4 of
PS-18 in Appendix B of this part.
2.9 Relative Accuracy (RA) means the value calculated using
Equation 15 of PS-18 in Appendix B of this part or as specified in
an applicable regulation. The RA is the absolute mean difference
between the gas concentration determined by the CEMS and the value
determined by the reference method (RM), plus the 2.5 percent error
confidence coefficient of a series of tests divided by the average
of the RM or the applicable emission standard.
3.0 QC Plan Requirements.
3.1 Each source owner or operator must develop and implement a
QC program. As a minimum, each QC program must include written
procedures and/or manufacturer's information which should describe
in detail, complete, step-by-step procedures and operations for each
of the following activities:
(a) CD checks of HCl CEMS;
(b) CD determination and adjustment of HCl CEMS;
(c) Integrated path HCl CEMS emission source (e.g., stack)
temperature and pressure accuracy;
(d) Integrated path HCl CEMS beam intensity checks;
(e) Routine and preventative maintenance of HCl CEMS (including
spare parts inventory);
(f) Data recording, calculations, and reporting;
(g) Accuracy audit procedures for HCl CEMS including sampling
and analysis methods; and
(h) Program of corrective action for malfunctioning HCl CEMS.
3.2 These written procedures must be kept on record and
available for inspection by the enforcement agency. As described in
section 5.3, whenever excessive inaccuracies occur for two
consecutive quarters, the source owner or operator must revise the
current written procedures or modify or replace the CEMS to correct
the deficiency causing the excessive inaccuracies.
4.0 Daily Quality Requirements, Calibration and Measurement
Standardization Procedures.
4.1 CD Assessment.
4.1.1 CD Requirement. As described in 40 CFR 60.13(d) and
63.8(c), source owners and operators of HCl CEMS must check, record,
and quantify the CD at two concentration values and at the
calibration range above span (CRAS) concentration value at least
once daily (approximately 24 hours) in accordance with the method
prescribed by the manufacturer. The HCl CEMS calibration must, at a
minimum, be adjusted whenever the daily zero (or low-level) CD or
the daily high-level CD exceeds two times the drift limits of the
applicable performance specification (e.g., PS-18 in Appendix B to
this part).
4.1.2 Recording Requirement for Automatic CD Adjusting CEMS. A
CEMS that automatically adjusts the data to the corrected
calibration values (e.g., microprocessor control) must be programmed
to record the unadjusted concentration measured in the CD prior to
resetting the calibration, if performed, or record the amount of
adjustment.
4.1.3 Criteria for Excessive CD. If either the zero (or low-
level) or high-level CD result exceeds twice the drift requirement
in the applicable performance specification in Appendix B of this
part for five consecutive daily periods, the CEMS is out-of-control.
If either the zero (or low-level) or high-level CD result exceeds
four times the applicable drift specification during any CD check,
the CEMS is out-of-control. If the CEMS is out-of-control, take
necessary corrective action. Following corrective action, repeat the
CD checks.
4.1.4 Out-Of-Control Period Definition. The beginning of the
out-of-control period for the CEMS calibration is the time
corresponding to the completion of the fifth consecutive daily check
with a CD in excess of two times the allowable limit, or the time
corresponding to the completion of the daily CD check preceding the
daily CD check that results in a CD in excess of four times the
allowable limits. The end of the out-of-control period is the time
corresponding to the completion of the CD check following corrective
action that results in the CDs at both the zero (or low-level) and
high-level measurement points being within the corresponding
allowable CD limit (i.e., either two times or four times the
allowable limit of the applicable rule).
4.2 Beam Intensity Requirement for HCl integrated path-CEMS (IP-
CEMS).
4.2.1 Beam Intensity Verification. Source owners and operators
of HCl IP-CEMS must quantify and record the beam intensity of their
IP-CEMS in appropriate units at least once daily (approximately 24
hours apart) according to manufacturer's specifications and
procedures.
4.2.2 Criteria for Excessive Beam Intensity Loss. If the beam
intensity falls below the level established for the operation range
determined following the procedures in section 11.2 of PS-18 of this
part, then the HCl CEMS is out-of-control. This quality check is
independent of whether the HCl CEMS daily calibration drift is
acceptable. If the HCl CEMS is out-of-control, take necessary
corrective action. Following corrective action, repeat the beam
intensity check.
4.3 CEMS Data Status During Out-of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used in
calculating compliance with an emissions limit nor be counted
towards meeting minimum data availability as required and described
in the applicable regulation or permit.
5.0 Data Accuracy Assessment.
Each CEMS must be audited at least once each calendar quarter.
Successive quarterly audits shall occur no closer than two months.
5.1 Temperature and Pressure Accuracy Assessment for IP CEMS.
5.1.1 Stack or source gas temperature measurement audits for HCl
IP-CEMS must be conducted and recorded at least quarterly in
accordance with the procedure described in section 11.3 of PS-18 in
Appendix B of this part. Any measurement instrument or device that
is used to conduct ongoing verification of temperature measurement
must have an accuracy that is traceable to NIST.
5.1.2 Stack or source gas pressure measurements for HCl IP-CEMS
must be checked and recorded at least quarterly in accordance with
the procedure described in section 11.4 of PS-18 in Appendix B of
this part. Any measurement instrument or device that is used to
conduct ongoing verification of pressure measurement must have an
accuracy that is traceable to NIST.
5.1.3 Excessive Parameter Verification Inaccuracy. If the
temperature or pressure verification exceeds the criteria in section
5.3.5, the HCl CEMS is out-of-control. If the CEMS is out-of-
control, take necessary corrective action to eliminate the problem.
Following corrective action, the source owner or operator must
repeat the failed verification to determine if the HCl CEMS is
operating within the specifications.
5.2 Concentration Accuracy Auditing Requirements. The accuracy
of each HCl CEMS must be audited at least once each calendar quarter
(except the quarter the relative accuracy audit test (RATA) is
conducted) by dynamic spiking audit (DSA), a cylinder gas audit
(CGA), a relative accuracy audit (RAA), or other acceptable
alternative. Successive quarterly audits must occur no closer than
two months apart. The accuracy audits shall be conducted as follows:
5.2.1 Relative Accuracy Test Audit. The RATA must be conducted
at least once every four calendar quarters, except as otherwise
noted in section 5.2.5 of this procedure. Unless otherwise specified
in an applicable regulation or permit, conduct the RATA during
process operating conditions representing average production and
full control operation at the source as specified in section 11.9.4
of PS-18 in Appendix B of this part.
5.2.1.1 Repeating the stratification test in section 11.9.3 is
not required unless the flow path of the emission stream has been
altered or changed since the initial RATA.
5.2.1.2 You must analyze and pass the appropriate performance
audit samples for the reference method (i.e., Method 26 and Method
26A) as described in the general provisions to the applicable part
(e.g. 40 CFR part 60 or 63).
5.2.1.3 If the measured source concentration during a RATA is 20
percent or less than the applicable emission standard, you must
perform a CGA or a DSA for at least one subsequent (one of the
following three) quarterly audits.
5.2.2 Quarterly Cylinder Gas Audit. A quarterly CGA may be
conducted as an option to conducting a RATA in three of four
calendar quarters, but in no more than three quarters in succession.
5.2.2.1 To perform a CGA, challenge the CEMS with a zero-level
and two upscale
[[Page 27714]]
level audit gases of known concentrations within the following
ranges:
------------------------------------------------------------------------
Audit point Audit range
------------------------------------------------------------------------
1 (Mid-Level)............................. 50 to 60% of span value.
2 (High-Level)............................ 80 to 120% of span value.
------------------------------------------------------------------------
5.2.2.2 Sequentially inject each of the three audit gases (zero
and two upscale) three times each for a total of nine injections.
Inject the gases in such a manner that the entire CEMS is
challenged. Do not inject the same gas concentration twice in
succession.
5.2.2.3 Use HCl audit gases that are NIST certified or NIST
traceable. Cylinder gases must be certified accurate to a tolerance
of five percent or less.
5.2.2.4 Calculate results as described in section 6.3.
5.2.3 Dynamic Spiking Audit (DSA). A DSA may be conducted as an
option to a RATA in three of four calendar quarters, but in no more
than three quarters in succession.
5.2.3.1 To conduct a DSA, you must conduct the dynamic spiking
procedure as described in Appendix A to PS-18 of Appendix B to this
part.
5.2.3.2 You must calculate the mean and relative standard
deviation for dynamic spiking measurements to determine CEMS
accuracy.
5.2.3.3 For extractive HCl CEMS, you must perform the DSA by
passing the spiked source gas through all filters, scrubbers,
conditioners and other monitoring system components used during
normal sampling, and as much of the sampling probe as is practical.
For IP-CEMS, you must perform the DSA by adding or passing a known
concentration calibration gas into a calibration cell in the optical
path of the CEMS. You must include the source measurement optical
path while performing a DSA using an IP-CEMS.
5.2.4 Relative Accuracy Audit (RAA). As an alternative to a CGA
or DSA, an RAA may be conducted in one to three of four calendar
quarters. To conduct an RAA, follow the RATA test procedures in
section 11.9 of PS-18 in Appendix B to this part, except that only
three test runs are required.
5.2.5 Other Alternative Quarterly Audits. Other alternative
audit procedures, as approved by the Administrator, may be used for
three of four calendar quarters. One RATA is required at least every
four calendar quarters, except in the case where the affected
facility is off-line (does not operate in the fourth calendar
quarter since the quarter of the previous RATA). In that case, the
RATA shall be performed in the quarter in which the unit recommences
operation. Also, a CGA, DSA, RAA, or RATA is not required for
calendar quarters in which the affected facility does not operate.
5.3 Excessive Audit Inaccuracy. If the results of the RATA, the
DSA, CGA, or RAA exceed the criteria in section 5.3.5, the HCl CEMS
is out-of-control. If the CEMS is out-of-control, take necessary
corrective action to eliminate the problem. Following corrective
action, the source owner or operator must audit the CEMS with a
RATA, DSA, CGA, or RAA to determine if the HCl CEMS is operating
within the specifications.
5.3.1 A RATA must always follow an out-of-control period
resulting from a RATA.
5.3.2 If the audit results show the CEMS to be out-of-control,
the CEMS operator shall report both the audit showing the CEMS to be
out-of-control and the results of the audit following corrective
action showing the CEMS to be operating within specifications.
5.3.3 Out-Of-Control Period Definition. The beginning of the
out-of-control period is the time corresponding to the completion of
the sampling for the failed RATA, CGA or DSA. The end of the out-of-
control period is the time corresponding to the completion of the
sampling of the subsequent successful audit.
5.3.4 CEMS Data Status During Out-Of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used in
calculating emission compliance nor be counted towards meeting
minimum data availability as required and described in the
applicable regulation or permit.
5.3.5 Criteria for Excessive Quarterly Test Inaccuracy. Unless
specified otherwise in the applicable regulation or permit, the
criteria for excessive inaccuracy are:
(a) For the RATA, the allowable RA is equal to 20 percent of the
RM when RMavg is used in the denominator of equation 15
in PS-18 of Appendix B to this part. In cases where the average
emission level for the test is less than 50 percent of the
applicable standard, you may substitute the equivalent emission
standard value (in ppmvw) in the denominator of equation 15 in the
place of RMavg and this alternative calculation of RA
must be less than or equal to 15 percent of the RM.
(b) For CGA, the allowable calibration error in PS-18 of
Appendix B to this part is applicable (less than five percent of
span).
(c) For the DSA, the allowable RA is + 15 percent of the average
spike value or 20 percent of the applicable emission
standard at source conditions under the production rate during the
time of the DSA, whichever is greater.
(d) For temperature verification, the CEMS must satisfy the
requirements in section 13.5.4 in PS-18 of Appendix B to this part.
(e) For pressure verification, the CEMS must satisfy the
requirements in section 13.5.5 in PS-18 of Appendix B to this part.
5.4 Criteria for Acceptable QC Procedures. Repeated excessive
inaccuracies (i.e., out-of-control conditions resulting from the
quarterly audits) indicate that the QC procedures are inadequate or
that the CEMS is incapable of providing quality data. Therefore,
whenever excessive inaccuracies occur for two consecutive quarters,
the source owner or operator must revise the QC procedures (see
section 3.0) or modify or replace the CEMS.
5.5 Criteria for Optional QA Test Frequency. If all the quality
criteria are met in section 4 and 5 of this procedure, the CEMS is
in-control.
5.5.1 If the CEMS is in-control and if the source releases <= 75
percent of the HCl emission limit for eight consecutive quarters
that include a minimum of two RATA, the source owner or operator may
revise their auditing procedures to use CGA, RAA or DSA each quarter
for eight subsequent quarters following a RATA.
5.5.2 The source owner or operator must perform at least one
RATA that meets the acceptance criteria every two years.
If the source owner or operator fails a RATA, CGA, or DSA, then
the audit schedule in section 5.2 must be followed until the audit's
results meet the criteria in section 5.3.5 to start requalifying for
the optional QA test frequency in section 5.5.
6.0 Calculations for CEMS Data Accuracy.
6.1 RATA RA Calculation. Follow equation 15 in Section 12 of PS-
18 in Appendix B to this part to calculate the RA for the RATA. The
RATA must be calculated in units of the applicable emission
standard.
6.2 CGA Accuracy Calculation. For each reference gas
concentration, determine the average of the three CEMS responses and
subtract the average response for the reference gas value. For
extractive HCl CEMS, calculate the measurement error at each gas
level using Equation 3 in section 12.3 of PS-18 in Appendix B to
this part. For IP-CEMS, calculate the measurement error at each gas
level using Equation 6 in section 12.6 of PS-18. Calculate CGA
accuracy in units of the appropriate concentration (e.g., ppmvd, lb/
MWhr, lb/MMBtu).
6.3 DSA Accuracy Calculation.
6.3.1 For extractive HCl CEMS, use the equations described in
section 11.2 in Appendix A of PS-18 of this part to calculate the
accuracy for the dynamic spike accuracy assessment. The DSA reported
as the percent spike recovery accuracy (%SA) must be calculated in
units of the applicable emission standard (e.g., ppmv).
6.3.2 For HCl IP-CEMS, use the equations described in section
11.3 in Appendix A of PS-18 to this part to calculate the accuracy
for the dynamic spike accuracy assessment for IP-CEMS. The DSA
reported as the percent spike recovery accuracy (%SA) must be
calculated in units of the applicable emission standard (e.g.,
ppmvd, lb/MWhr, lb/MMBtu).
7.0 Reporting Requirements.
At the reporting interval specified in the applicable regulation
or permit, report for each CEMS the accuracy results from section 6
and the CD assessment results from section 4.
7.1 Report the drift and accuracy information as a Data
Assessment Report (DAR), and include one copy of this DAR for each
quarterly audit with the report of emissions required under the
applicable subparts of this part or other applicable regulations or
permits. An example of a DAR format is shown in Figure 1.
7.1.1 At a minimum, the DAR must contain the following
information:
a. Source owner or operator name and address.
b. Identification and location of monitors in the CEMS.
c. Manufacturer and model number of each monitor in the CEMS.
d. Assessment of CEMS data accuracy and date of assessment as
determined by a RATA, CGA or DSA described in section 5 including:
The RA for the RATA;
The RA for the CGA or DSA;
Beam intensity results for IP-CEMS;
[[Page 27715]]
The RM results, the cylinder gases certified values;
The CEMS responses;
The calculations results as defined in section 6;
Results from EPA performance audit samples described in
section 5 and the applicable RMs; and
Summary of all corrective actions taken when CEMS was
determined out-of-control, as described in sections 4 and 5.
7.1.2 If the accuracy audit results show the CEMS to be out-of-
control, the CEMS operator shall report both the audit results
showing the CEMS to be out-of-control and the results of the audit
following corrective action showing the CEMS to be operating within
specifications.
8.0 Bibliography.
1. ``A Procedure for Establishing Traceability of Gas Mixtures
to Certain National Bureau of Standards Standard Reference
Materials.'' Joint publication by NBS and EPA-600/7-81--10, Revised
1989. Available from the U.S. Environmental Protection Agency.
Quality Assurance Division (MD-77). Research Triangle Park, NC
27711.
2. Method 205, ``Verification of Gas Dilution Systems for Field
Instrument Calibrations,'' 40 CFR 51, appendix M.
9.0 Tables, Diagrams, Flowcharts and Validation Data.
9.1 Accuracy assessment results. Complete the applicable DAR
sections (A, B and C) for each CEMS or for each pollutant and
diluent analyzer, as applicable. If the quarterly audit results show
the CEMS to be out-of-control, report the results of both the
quarterly audit and the audit following corrective action showing
the CEMS to be operating properly.
Figure 1--Example Format for Data Assessment Report
Period ending date
------------------------------------------------------------------------
Year
------------------------------------------------------------------------
Company name
------------------------------------------------------------------------
Plant name
------------------------------------------------------------------------
Source unit No.
------------------------------------------------------------------------
CEMS manufacturer
------------------------------------------------------------------------
Model No.
------------------------------------------------------------------------
CEMS serial No.
------------------------------------------------------------------------
CEMS type (e.g., extractive, integrated path)
------------------------------------------------------------------------
CEMS sampling location (e.g., control device outlet)
------------------------------------------------------------------------
CEMS span values as per the applicable regulation: ------------ (e.g.,
HCl ppmv)
A--Relative Accuracy Test Audit (RATA) for HCl in ppmv
1. Date of audit ------------
------------------------------------------------------------------------
2. Reference methods (RMs) used ------------ (e.g., Methods 26A, 320,
321).
------------------------------------------------------------------------
3. Average RM value ---- (e.g., lb/MMw, ng/J, mg/dsm \3\, or percent
volume).
------------------------------------------------------------------------
4. Average CEMS value ---- .
------------------------------------------------------------------------
5. Absolute value of mean difference [d] ----.
------------------------------------------------------------------------
6. Confidence coefficient [CC] ----.
------------------------------------------------------------------------
7. Percent relative accuracy (RA) ---- percent.
------------------------------------------------------------------------
8. * Method 26A performance audit results:
a. Audit lot number (1) ---- (2) ----
------------------------------------------------------------------------
b. Audit sample number (1) ---- (2) ----
------------------------------------------------------------------------
c. Results (mg/dsm \3\) (1) ---- (2) ----
------------------------------------------------------------------------
d. Actual value (mg/dsm \3\) (1) ---- (2)----
------------------------------------------------------------------------
e. Relative error (1) ---- (2) ----
* As applicable
B--Cylinder Gas Audit (CGA) for HCl in ppmv
----------------------------------------------------------------------------------------------------------------
Audit point 1 Audit point 2
----------------------------------------------------------------------------------------------------------------
1. Date of audit
2. Cylinder ID number
3. Date of certification
4. Type of certification.......... .......................... .......................... e.g., EPA Protocol 1
or CRM).
5. Certified audit value.......... .......................... .......................... (e.g., ppm).
6. CEMS response value............ .......................... .......................... (e.g., ppm).
[[Page 27716]]
7. Accuracy....................... .......................... .......................... Percent.
----------------------------------------------------------------------------------------------------------------
C--Dynamic Spiking Audit (DSA) for HCL in ppmv
----------------------------------------------------------------------------------------------------------------
Concentration 1 Concentration 2 Concentration 3
----------------------------------------------------------------------------------------------------------------
1. Date of audit
----------------------------------------------------------------------------------------------------------------
2. Effective Spike Addition
(ppmv)
----------------------------------------------------------------------------------------------------------------
3. Average CEMS value
----------------------------------------------------------------------------------------------------------------
4. Spike Recovery Accuracy (%SA)
----------------------------------------------------------------------------------------------------------------
5. Average Recovery Accuracy (%SA
average.)
----------------------------------------------------------------------------------------------------------------
[FR Doc. 2014-10824 Filed 5-13-14; 8:45 am]
BILLING CODE 6560-50-P