[Federal Register Volume 62, Number 109 (Friday, June 6, 1997)]
[Proposed Rules]
[Pages 31025-31037]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-14848]
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[AZ 69-0012; FRL-5836-9]
Approval and Promulgation of Implementation Plans; Arizona--
Maricopa County PM-10 Nonattainment Area
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
-----------------------------------------------------------------------
SUMMARY: EPA is proposing to approve in part and disapprove in part the
final Plan for Attainment of the 24-hour PM-10 Standard--Maricopa
County PM-10 Nonattainment Area, (May 1997) (plan or microscale plan)
submitted by the Arizona Department of Environmental Quality on May 7,
1997. The microscale plan evaluates attainment of the 24-hour
particulate matter (PM-10) national ambient air quality standard at
four monitoring locations in the Maricopa County (Phoenix), Arizona,
PM-10 nonattainment area. EPA is proposing to approve the attainment
and reasonable further progress (RFP) demonstrations for two of these
sites (Salt River and Maryvale) and disapprove them for two other sites
(West Chandler and Gilbert). EPA is also proposing to approve the
reasonably available control measure/best available control measure
(RACM/BACM) demonstrations in the
[[Page 31026]]
microscale plan for some significant source categories of PM-10, but
disapprove them for others.
DATES: Comments on this proposal must be received in writing by June
20, 1997.
ADDRESSES: Comments should be addressed to the contact listed below.
Copies of the State's submittals, the technical support document,
and other information are contained in the docket for this rulemaking.
A copy of this notice and the TSD are also available in the air
programs section of EPA Region 9's website, http://www.epa.gov/
region09. The docket is available for inspection during normal business
hours at the following locations:
U.S. Environmental Protection Agency, Region 9, Office of Air Planning,
Air Division, 17th Floor, 75 Hawthorne Street, San Francisco,
California 94105, (415) 744-1248.
Arizona Department of Environmental Quality, Office of Outreach and
Information, First Floor, 3033 N. Central Avenue, Phoenix, Arizona
85012, (602) 207-2217.
Maricopa County Environmental Services Department, Technical Services
Division, 1001 N. Central Avenue, Suite 201, Phoenix, Arizona 85004,
(602) 506-6010.
FOR FURTHER INFORMATION CONTACT: Frances Wicher, Office of Air Planning
(AIR-2), U.S. Environmental Protection Agency, Region 9, 75 Hawthorne
Street, San Francisco, California 94105. (415) 744-1248.
SUPPLEMENTARY INFORMATION:
I. Background
A. Clean Air Act Requirements
1. Designation and Classification
On the date of enactment of the 1990 Clean Air Act Amendments, PM-
10 areas meeting the conditions of section 107(d) of the Act, including
portions of Maricopa County (the Maricopa County PM-10 nonattainment
area), were designated nonattainment for the PM-10 national ambient air
quality standards (NAAQS) 1 by operation of law. Once an
area is designated nonattainment, section 188 of the Clean Air Act
(CAA) outlines the process for classification of the area and
establishes the area's attainment date. In accordance with section
188(a), at the time of designation, all PM-10 nonattainment areas were
initially classified as ``moderate'' by operation of law. 56 FR 11101
(March 15, 1991).
---------------------------------------------------------------------------
\1\ There are two PM-10 NAAQS, a 24-hour standard and an annual
standard. 40 CFR 50.6.
---------------------------------------------------------------------------
A moderate area could subsequently be reclassified as ``serious''
under CAA section 188(b)(1), if at any time, EPA determined that the
area could not practicably attain the PM-10 NAAQS by the applicable
attainment date for moderate areas, December 31, 1994. Moreover, a
moderate area was reclassified by operation of law if EPA determined
after the applicable attainment date that, based on actual air quality
data, the area was not in attainment after that date. CAA section
188(b)(2).
On May 10, 1996, EPA published a final reclassification of the
Maricopa County PM-10 nonattainment area as a serious PM-10
nonattainment area based on actual air quality data. 61 FR 21372.
Having been reclassified, the area is required to meet the serious area
requirements in the CAA, including a demonstration that the area will
attain the PM-10 NAAQS as expeditiously as practicable but no later
than December 31, 2001. CAA sections 188(c)(2) and 189(b). Pursuant to
section 189(b)(2), the State of Arizona must submit a serious area plan
addressing both PM-10 NAAQS for the area by December 10, 1997.
2. Moderate Area Planning Requirements
The air quality planning requirements for PM-10 nonattainment areas
are set out in subparts 1 and 4 of title I of the Clean Air Act. EPA
has issued a ``General Preamble'' 2 describing EPA's
preliminary views on how the Agency intends to review SIPs and SIP
revisions submitted under Title I of the Act, including those state
submittals containing moderate PM-10 nonattainment area SIP provisions.
---------------------------------------------------------------------------
\2\ See ``State Implementation Plans; General Preamble for the
Implementation of Title I of the Clean Air Act Amendments of 1990,''
57 FR 13498 (April 16, 1992) and 57 FR 18070 (April 28, 1992).
---------------------------------------------------------------------------
Those states containing initial moderate PM-10 nonattainment areas
were required to submit, among other things, the following provisions
by November 15, 1991:
(a) Provisions to assure that reasonably available control measures
(RACM) (including such reductions in emissions from existing sources in
the area as may be obtained through the adoption, at a minimum, of
reasonably available control technology (RACT)) shall be implemented no
later than December 10, 1993 (CAA sections 172(c)(1) and 189(a)(1)(C));
(b) Provisions to assure implementation of RACT on major stationary
sources of PM-10 precursors except where EPA has determined that such
sources do not contribute significantly to exceedances of the PM-10
standards (CAA section 189(e));
(c) Either a demonstration (including air quality modeling) that
the plan will provide for attainment as expeditiously as practicable
but no later than December 31, 1994 or a demonstration that attainment
by that date is impracticable (CAA sections 188(c)(1) and
189(a)(1)(B));
(d) For plan revisions demonstrating attainment, quantitative
milestones which are to be achieved every 3 years and which demonstrate
reasonable further progress (RFP) toward attainment by December 31,
1994 (CAA section 189(c)); 3 and
---------------------------------------------------------------------------
\3\ As will be seen below, the moderate area PM-10 plan for the
Maricopa area did not demonstrate attainment by December 31, 1994,
but rather included the alternative demonstration that attainment by
that date is impracticable. Therefore, section 189(c) did not apply
to the State's moderate area plan.
---------------------------------------------------------------------------
(e) For plan revisions demonstrating impracticability, such annual
incremental reductions in PM-10 emissions as are required by part D of
the Act or may reasonably be required by the Administrator for the
purpose of ensuring attainment of the PM-10 NAAQS by the applicable
attainment date (CAA sections 172(c)(2) and 171(1)).
Moderate area plans were also required to meet the generally
applicable SIP requirements for reasonable notice and public hearing
under section 110(l), necessary assurances that the implementing
agencies have adequate personnel, funding and authority under section
110(a)(2)(E)(i) and 40 CFR Sec. 51.280; and the description of
enforcement methods as required by 40 CFR Sec. 51.111, and EPA guidance
implementing these sections.
3. Serious Area Planning Requirements
EPA has issued an Addendum to the General Preamble (Addendum)
describing the Agency's preliminary views on how it intends to review
SIPs and SIP revisions containing serious area plan
provisions.4
---------------------------------------------------------------------------
\4\ See ``State Implementation Plans for Serious PM-10
Nonattainment Areas, and Attainment Date Waivers for PM-10
Nonattainment Areas Generally; Addendum to the General Preamble for
the Implementation of Title I of the Clean Air Act Amendments of
1990,'' 59 FR 41998 (August 16, 1996).
---------------------------------------------------------------------------
Moderate PM-10 areas that have been reclassified to serious, such
as the Maricopa area, in addition to meeting the moderate area
requirements outlined above, must submit a plan that includes
provisions addressing additional requirements. The additional serious
area requirements that are relevant to this proposed action include:
(a) Provisions to assure that the best available control measures
(BACM)
[[Page 31027]]
(including such reductions in emissions from existing sources in the
area as may be obtained through the adoption, at a minimum, of best
available control technology (BACT)) for the control of PM-10 shall be
implemented no later than 4 years after the area is reclassified (CAA
section 189(b)(1)(B));
(b) Provisions to assure implementation of BACT on major stationary
sources of PM-10 precursors except where EPA has determined that such
sources do not contribute significantly to exceedances of the PM-10
standards (CAA section 189(e));
(c) A demonstration (including air quality modeling) that the plan
will provide for attainment as expeditiously as practicable but no
later than December 31, 2001 (CAA sections 188(c)(2) and
189(b)(1)(A)(i)); 5 and
---------------------------------------------------------------------------
\5\ Section 189(b)(1)(A)(ii) provides for an alternative
demonstration of impracticability similar to that available for
moderate areas. Since the State did not make such a demonstration,
this alternative requirement is not addressed in this notice.
---------------------------------------------------------------------------
(d) For plan revisions demonstrating attainment, quantitative
milestones which are to be achieved every 3 years and which demonstrate
RFP toward attainment by December 31, 2001 (CAA section 189(c)).
As discussed above in connection with the moderate area plan
requirements, SIPs submitted to meet the CAA's serious area
requirements must conform to general requirements applicable to all
SIPs.
B. EPA Approval of Arizona's Moderate Area PM-10 Plan
On July 28, 1994, EPA proposed to approve the State's moderate area
PM-10 implementation plan revision for the Maricopa area. 59 FR 38402.
Among other elements in that plan, EPA proposed to approve the State's
RFP and RACM demonstrations as meeting the requirements of sections
171(1), 172(c)(1), 172(c)(2), and 189(a)(1)(C) of the CAA. Based on its
approval of the RACM demonstration, EPA also proposed to approve, as
meeting the requirements of section 189(a)(1)(B), the State's
demonstration that even with the implementation of all RACM by December
10, 1993, it was impracticable for the Maricopa area to attain the PM-
10 NAAQS by December 31, 1994.6
---------------------------------------------------------------------------
\6\ The reader should refer to both the proposed approval, 59 FR
38402, and the final rule, 60 FR 18010 (April 10, 1995), for EPA's
interpretation of the certain moderate area PM-10 requirements of
the CAA and the Agency's application of these interpretations to the
State's moderate area PM-10 plan. Those notices should also be
consulted for the history of the State's PM-10 plan submittals and
EPA's actions concerning them.
---------------------------------------------------------------------------
During the public comment period on the EPA's proposed action, the
Arizona Center for Law in the Public Interest (ACLPI) submitted lengthy
comments on many aspects of EPA's proposed approval of the State's
moderate area PM-10 plan. Among ACLPI's comments were claims that the
plan as submitted failed in numerous respects to meet the moderate area
requirements of the CAA for RACM, RFP and attainment demonstrations.
ACLPI further claimed that the State's impracticability and RACM
demonstrations were additionally deficient in that the State had failed
to address both the annual and 24-hour PM-10 standards as required by
the CAA and EPA guidance. In response to this comment, EPA concluded
that the State's demonstration that the Maricopa area could not
practicably attain the annual standard was sufficient to meet the
requirements of section 189(a)(1)(B) and therefore a separate analysis
was not necessary for the 24-hour standard.
On April 10, 1995, having considered ACLPI's comments, EPA
published a final rule in the Federal Register approving the State's
moderate area PM-10 SIP for the Maricopa area. 60 FR 18010. In its
final action, EPA approved, among other elements of the plan, the
State's RACM and RFP demonstrations, and the State's demonstration that
even with the implementation of all RACM by December 10, 1993, it was
not practicable for the Maricopa area to attain the PM-10 NAAQS by
December 31, 1994.
C. Ninth Circuit Litigation
On May 1, 1995, ACLPI filed, on behalf of two Phoenix residents, a
petition for review, Ober v. EPA, No. 95-70352, of EPA's approval of
Arizona's moderate area PM-10 plan for the Maricopa area in the United
States Court of Appeals for the Ninth Circuit. On May 14, 1996, the
court issued its opinion in the Ober case vacating EPA's approval of
the State's plan. 7
---------------------------------------------------------------------------
\7\ The reader is referred to the text of the opinion for the
court's disposition of the range of issues raised by ACLPI in its
petition. 84 F.3d 304 (9th Cir. 1996). This notice addresses that
disposition only as it relates to the 24-hour standard. See also 61
FR 54972 (October 23, 1996) in which EPA preliminarily addresses the
court's opinion as it relates to the RACM, RFP and attainment
demonstrations for the annual standard.
---------------------------------------------------------------------------
As it relates to this proposed rulemaking, the court found that the
State was required to address in its SIP the moderate area requirements
in the CAA regarding RFP, RACM and attainment or impracticability for
both the 24-hour and the annual PM-10 NAAQS. The court concluded that
because there are two separate NAAQS for PM-10, the CAA requires an
implementation plan to address each of them. In order to remedy the
failure of the State to address the required demonstrations for the 24-
hour standard, the court required EPA to in turn require the State to
submit those demonstrations. 84 F.3d at 311.
D. EPA's Response to the Ober Opinion
In the wake of the Ninth Circuit's Ober opinion, EPA considered how
to appropriately implement the court's directive in the context of the
State's then prevailing PM-10 planning efforts for the Maricopa area.
The Maricopa area was reclassified as a serious PM-10 nonattainment
area just days before the case was decided and, as noted above, the
State is now required to submit a new PM-10 plan meeting the serious
area requirements by December 10, 1997. Simply put, EPA had to
reconcile, with respect to both timing and content, the court's mandate
that the State submit a plan correcting its moderate area plan
deficiencies regarding the 24-hour standard concurrent with its
responsibility to submit a plan meeting the serious area requirements
for both NAAQS.
1. Timing
As an initial matter, EPA concluded that, given the substantial
overlap of the moderate and serious area planning requirements, it
would not be in the public interest to require the State to divert its
scarce resources into two independent planning exercises. At the same
time the Agency recognized that deferring submittal of a plan
addressing the moderate area plan deficiencies until the serious area
submittal deadline of December 10, 1997 would not constitute a timely
response to the court. Therefore EPA, in consultation with the Arizona
Department of Environmental Quality (ADEQ) and the Maricopa County
Environmental Services Department (MCESD), decided that the State would
incorporate the moderate area plan elements for the 24-hour standard
into the serious area plan, but would split that planning effort into
two related parts. Accordingly, EPA required submittal of a limited,
locally-targeted plan (microscale plan) meeting both the moderate and
serious area requirements for the 24-hour standard by May 9, 1997
(extended from an original deadline of April 18) and a full regional
plan meeting those requirements for both the 24-hour and annual
standards by December 10, 1997. Thus, the microscale and regional plans
taken together would satisfy both the moderate area requirements
mandated by the court and the serious area planning requirements for
both
[[Page 31028]]
standards. Therefore, until the regional plan is submitted and reviewed
by EPA, it is premature to conclude that the microscale plan fully
meets or does not meet the CAA requirements discussed below. The
subject of this proposed action is the microscale plan only.
The submittal deadlines and statutory requirements applicable to
the microscale plan are contained in letters dated September 18, 1996
and March 5, 1997 from Felicia Marcus, Regional Administrator, EPA
Region IX, to Russell Rhoades, Director, ADEQ (Marcus letter).
2. Content
As specified in EPA's September 18, 1996 letter to ADEQ, the
microscale plan was to address the 24-hour standard violations at five
specific monitors and meet the statutory attainment, RACM and RFP
requirements for moderate PM-10 areas and EPA guidance. In addition,
the microscale plan was to meet the statutory attainment, BACM and RFP
requirements for serious PM-10 areas and EPA guidance at 59 FR 41998.
Further, the plan was to contain the air quality modeling and emissions
inventory information necessary to support these attainment, RFP, RACM,
and BACM demonstrations and must meet the general SIP requirements
discussed above.
Having concluded that the hybrid moderate/serious plans described
above would effectuate the intent of the Ninth Circuit's mandate, EPA
then turned to the issue of how to define the moderate area
requirements applicable to the microscale plan after the moderate area
attainment deadline, December 31, 1994, has passed. The following
discussion addresses that issue and the interrelationship of those
requirements with the serious area requirements as they apply to that
plan.
(a) Attainment Demonstration. EPA believes that because the
Maricopa area was reclassified from a moderate to a serious
nonattainment area, the moderate area requirements (demonstration of
impracticability or attainment by no later than December 31, 1994) have
been superseded by the serious area attainment requirement (attainment
by no later than December 31, 2001) and are therefore now moot. Having
reviewed the CAA's moderate and serious area PM-10 attainment
provisions, EPA has concluded that when a moderate PM-10 area has been
reclassified after the moderate area attainment deadline has passed and
been replaced with a new deadline, the moderate area deadline no longer
has any logical, practical or legal significance.
Thus, under this interpretation, there would be no need for the
State's microscale plan, to the extent that it is intended to meet the
CAA's moderate area requirements, to demonstrate attainment. In other
words, such an attainment demonstration would only be required when the
State submits in late 1997 the complete serious area plan to comply
with the section 189(b)(1) attainment demonstration requirement. EPA
believes that its interpretation can be reconciled with the Ober
court's directive that EPA require the State to address the moderate
area attainment requirements for the 24-hour standard and that such an
interpretation is reasonable given the legal and factual context in
which that case was decided. EPA's reasoning is explained in detail at
61 FR 54972, 54974-54975 (October 23, 1996). Nevertheless, EPA has
chosen to comply with the court's remedies regarding the moderate area
attainment requirements. 8
---------------------------------------------------------------------------
\8\ While EPA could have sought clarification from the Ninth
Circuit in order to apply its interpretation in the context of
compliance with the court's remedies in Ober, the Agency did not
believe that it would have been in the public interest to do so.
Such a review would necessarily have occurred without benefit of a
thorough briefing on the issue and in the absence of an
administrative record. The Agency does, however, reserve its right
to assert its interpretation in any challenge to EPA's
implementation of the court's remedies or in the context of other
reclassifications. Because EPA is not applying this interpretation
in this rulemaking, it does not constitute final agency action.
---------------------------------------------------------------------------
Having determined that it must require the State to meet the CAA's
moderate attainment requirements for the 24-hour standard, EPA has
concluded that since the December 31, 1994 deadline has passed and the
Maricopa area has been reclassified, the only attainment deadline
currently applicable to the area is the serious area deadline, that is,
no later than December 31, 2001. Thus the attainment deadline for both
the moderate and serious area components of the State's microscale PM-
10 plan would be as expeditiously as practicable but no later than
December 31, 2001. Therefore, if the microscale plan demonstrates
attainment of the 24-hour standard at each monitor specified in EPA's
September 18, 1996 letter by no later than December 31, 2001, it will
be deemed to comply with sections 189(a)(1)(B) and (b)(1)(A) of the
CAA.
(b) RACM/BACM Demonstration. Sections 172(c)(1) and 189(a)(1)(C)
read together require that moderate area PM-10 SIPs include RACM and
RACT for existing sources of PM-10. These SIPs were to provide for
implementation of RACM/RACT no later than December 10, 1993. Since the
moderate area deadline for the implementation of RACM/RACT has passed,
EPA has concluded that the RACM/RACT required in the State's microscale
plan must be implemented as soon as possible. Delaney v. EPA, 898 F.2d
687, 691 (9th Cir. 1990).
The methodology for determining RACM/RACT is described in detail in
the General Preamble. 57 FR at 13540-13541. In summary, EPA suggests
starting to define RACM with the list of available control measures for
fugitive dust, residential wood combustion, and prescribed burning
contained in Appendices C1, C2, and C3 of the General Preamble and
adding to this list any additional control measures proposed and
documented in public comments. The state can then cull from the list
any measures for insignificant emission sources of PM-10 and any
measures that are unreasonable for technological or economic reasons.
The General Preamble does not define insignificant except to say that
it would be unreasonable to apply controls to sources that are
negligible (``de minimis'') contributors to ambient concentrations.
However, EPA's serious area plan guidance does define, for use in BACM
determinations, a ``significant contributor'' source category as one
that contributes 5 g/m \3\ or more of PM-10 to a location of
expected 24-hour exceedances. Addendum at 42011. For purposes of the
microscale plan only, EPA is proposing to use this same definition to
define significant in determining which source categories require the
application of RACM.
For any RACM that are rejected by the state, the plan must provide
a reasoned justification for the rejection. Once the final list of RACM
is defined, each RACM must be converted into a legally enforceable
vehicle such as a rule, permit, or other enforceable document. General
Preamble at 13541.
Under section 189(b)(2), for moderate areas that have been
reclassified as serious, the state must submit BACM 18 months after
reclassification, i.e., December 10, 1997 for the Maricopa area, and
must implement those measures four years after reclassification, i.e.,
by June 10, 2000 for the Maricopa area.
BACM is defined as the ``maximum degree of emission reduction of
PM-10 and PM-10 precursors from a [significant] source [category] which
is determined on a case-by-case basis, taking into account energy,
environmental, and economic impacts and other costs, to be achievable
for such sources through application of
[[Page 31029]]
production processes and available methods, systems, and techniques * *
*.'' Addendum at 42010. BACM/BACT must be determined and documented
consistent with the Addendum (59 FR at 42012-14) and must be applied to
each significant area-wide source category and individual stationary
source. Addendum at 42010, footnote 33. A ``significant'' source
category is defined as one that contributes 5 g/m \3\ or more
of PM-10 to a location of expected 24-hour violation. Addendum at
42011.
The state must document its selection of BACM by showing what
control measures applicable to each significant source category were
considered. See Addendum at 42014. BACM should go beyond existing RACM
controls and can include expanded use of RACM controls (e.g., paving
more miles of unpaved roads). Addendum at 42013. Additionally, BACM
should emphasize prevention pf PM-10 emissions where possible over
remediation. Addendum at 42013.
For the microscale plan, EPA required that Arizona submit RACM and
BACM demonstrations by May 9, 1997 as they relate to exceedances of the
24-hour standard at the five specified monitors. RACM and BACM were to
be identified, documented, and realistically evaluated for
effectiveness for contributing sources to each modeled exceedance.
Marcus letter. Evaluation of RACM/BACM in the microscale plan is
limited to controls for sources that are contributing significantly and
directly to the localized violations rather than to sources
contributing to background PM-10 levels. A full analysis of RACM/BACM
for sources that significantly contribute to PM-10 levels in the
Maricopa County PM-10 nonattainment area but are not directly
implicated in the localized exceedances is to be conducted as part of
the regional serious area plan, due December 10, 1997.
(c) RFP/Quantitative Milestones. Both PM-10 moderate and serious
area nonattainment SIPs demonstrating attainment must include
quantitative milestones to be achieved every three years until the area
is designated attainment and must demonstrate RFP toward attainment by
the applicable date. CAA section 189(c)(1). EPA has addressed these
requirements in several guidance documents. See the General Preamble at
13539, the Addendum at 42015-42017, and the memorandum from Sally
Shaver, EPA, to EPA Division Directors, ``Criteria for Granting 1-Year
Extensions of Moderate PM-10 Nonattainment Area Attainment Dates,
Making Attainment Determinations, and Reporting on Quantitative
Milestones,'' November 14, 1994 (Shaver memorandum). Of these guidance
documents, the most comprehensive is the Addendum which discusses both
the RFP annual incremental reduction requirement and the appropriate
interpretation of the milestone requirement as it relates to moderate
areas that have been reclassified to serious.
With respect to RFP, EPA determined that SIPs must indicate the
annual emission reductions that correspond to the compliance schedules
for the control measures in the plan. EPA then has considerable
discretion in reviewing the SIP to determine whether the annual
incremental emission reductions to be achieved are reasonable in light
of the statutory objective of timely attainment. Addendum at 42015.
With respect to the quantitative milestone requirement, for initial
moderate areas, EPA concluded that the SIP should initially address at
least two milestones and that the starting point for the first 3-year
period would be the SIP submittal due date, i.e. November 15, 1991. EPA
further concluded that since the time lag between that date and the
December 31, 1994 attainment deadline was de minimis, emission
reduction progress made between the submittal date and December 31,
1994 would satisfy the first milestone. The second milestone to be
addressed by these initial moderate area SIPs was November 15, 1997.
General Preamble at 131539, Addendum at 42016, and Shaver memorandum.
For moderate areas that are reclassified as serious, the third
milestone achievement date is November 15, 2000. Addendum at 42016. The
quantitative milestones should consist of elements that allow progress
to be quantified or measured, e.g., percent compliance with implemented
control measures. Addendum at 42016.
EPA will assess whether an area has achieved RFP in conjunction
with determining compliance with the quantitative milestone
requirement. Thus a state should address compliance with both
requirements in its RFP/milestone reports. The contents of these
reports is discussed in the General Preamble, its Addendum, and the
Shaver memorandum.
Since the Ober court found that Arizona had failed to submit a
moderate area SIP addressing the 24-hour PM-10 standard in 1991 and the
regional plan addressing both the moderate and serious area
requirements for both PM-10 NAAQS is now due on December 10, 1997, EPA
believes that it is reasonable to conclude, by applying the de minimis
reasoning above, that the November 15, 1997 milestone can be satisfied
by the December plan submittal. Therefore, the microscale plan need not
address the CAA section 189(c)(1) quantitative milestone requirement
and it is not discussed further in this notice.
II. Evaluation of the State's Submittal
The Plan for Attainment of the 24-hour PM-10 Standard--Maricopa
County PM-10 Nonattainment Area (May, 1997) (microscale plan) was
submitted to EPA by the Arizona Department of Environmental Quality
(ADEQ) in draft on March 28, 1997 and in final on May 9, 1997. EPA has
found both submittals complete pursuant to CAA section 110(k) and 40
CFR part 51, Appendix V. Letter, David P. Howekamp, EPA, to Russell F.
Rhoades, ADEQ, May 23, 1997.9
---------------------------------------------------------------------------
\9\ ADEQ requested that EPA propose action on the draft plan in
parallel with the State's public comment period (see March 28, 1997
submittal letter); however, the final plan was submitted before EPA
could do so. Therefore, EPA's evaluation of the microscale plan, as
described in this notice, is based on the final plan and all
references in this notice are to that plan.
---------------------------------------------------------------------------
EPA has evaluated the plan for compliance with the applicable
statutory, regulatory, and policy requirements described above. This
evaluation is summarized here, and the detailed analysis can be found
in the technical support document which is located in the docket for
this proposed rulemaking.
A. Air Quality Modeling
1. The Microscale Approach
CAA section 189(b)(1)(A)(i) requires serious area plans to include
air quality modeling as part of their attainment demonstrations. For
the microscale plan, base case air quality modeling was required for
exceedances at the (East) Chandler,10 West Chandler,
Gilbert, and Maryvale monitors. For the Salt River monitor, air quality
modeling was required for each unique emissions scenario leading to an
exceedance. In addition, all modeling inputs had to be fully documented
and the air quality
[[Page 31030]]
modeling protocols must conform to EPA guidance or be approved in
advance by EPA. Marcus letter.
---------------------------------------------------------------------------
\10\ The East Chandler site was dropped from the microscale plan
because there was insufficient source activity information to
develop a useable inventory for modeling the exceedances at the
site. Plan, Appendix A, p. 3-1. From the information that is
available about the East Chandler site, it appears that exceedances
there have similar causes to those at the modeled West Chandler
site, that is, they are related to windblown dust during high winds
from a mix of urban and agricultural sources. See facsimiles, Randy
Sedlacek, ADEQ, to Frances Wicher, EPA, May 21, 1997 (found in the
docket). The Gilbert site also had similar source characteristics.
Plan, Appendix A, p. 4-7. Therefore, RACM/BACM implemented for the
West Chandler and Gilbert sites should also contribute to emission
reductions at the East Chandler site. Consequently there will be no
further reference to this site in this notice.
---------------------------------------------------------------------------
Base case air quality modeling attempts to replicate observed PM-10
NAAQS exceedances using historical observations of air quality,
meteorology, and emissions. The modeling results indicate what sources
are contributing to the exceedances and what level of emissions
reductions are needed to eliminate these exceedances.
The modeling approach used in the microscale plan is significantly
different than default approaches in EPA guidelines and approaches used
in other areas. The main concept of the approach used in the microscale
plan is that if PM-10 exceedances are caused mainly by relatively
nearby sources, then an attainment demonstration can be based on
modeling over a relatively small (microscale) geographic domain, i.e.,
over sub-areas of the nonattainment area. The microscale approach is
more fully described in Microscale Monitoring and Modeling Protocol for
the Maricopa PM-10 Nonattainment Area, Harding Lawson Associates,
August 31, 1994.
Normally, attainment demonstrations should address attainment for
the entire nonattainment area; however, emission inventory development
and modeling for areas with substantial fugitive dust problems, such as
the Maricopa area, have proved difficult because of the marked
uncertainty and temporal and spatial variability of fugitive dust
emissions. Fugitive PM-10 has more localized effects than the other
criteria pollutants because it is emitted near ground level and has
relatively sharp spatial gradients as dust settles out with distance
from the source. These considerations suggest that effort should be
focused on intensive inventorying and modeling of small areas and short
episodes. The approach in the microscale plan can be viewed as an
extension of the microinventory method cited in early EPA guidance on
PM-10 (Receptor Model Technical Series, Volume I, Overview of Receptor
Model Application to Particulate Source Apportionment, EPA-450-4-81-
016a, July 1981, p. 27) but goes a step further in using that emission
inventory as input into a dispersion model to enable a more precise
apportionment of the various sources' effects.
Nevertheless, sources can have effects farther away than is implied
by the term ``microscale.'' The finer component of fugitive PM-10 can
settle out relatively slowly, and during high wind conditions, at least
some of the larger component can be carried long distances. These
effects create a regional component that is not captured in the
emissions of a small area near a monitor. This regional component can
be dealt with as part of a regional modeling exercise or as part of a
``background'' to be added to the microscale results. The latter
approach is taken in the microscale plan. The fact that the background
levels in the plan are relatively high relative compared to the total
concentrations indicates a limitation of the microscale approach. Plan,
pp. 24-26. On the other hand, since fugitive dust control measures
derived from the microscale analysis area to be applied over the entire
nonattainment area, the background will likely also be reduced because
it too is made up primarily of fugitive dust. Therefore, keeping the
background constant between uncontrolled and controlled scenarios, as
is done in the microscale plan, makes for a conservative microscale
attainment demonstration, partly compensating for shortcomings in the
microscale approach.
EPA guidance for ozone and carbon monoxide modeling (e.g.,
Guideline for the Regulatory Application of the Urban Airshed Model,
EPA-450/4-91-013, July 1991) describes the selection of pollution
episodes to model; there is no comparable guidance for PM-10, but the
reasoning would be the same. Basically, the day(s) chosen should be
representative of the meteorological conditions and emissions scenarios
that lead to NAAQS exceedances and have an adequate database for the
development of model inputs. In addition, a microscale approach must
ensure that the particular sites chosen for modeling are worst case or
representative of PM-10 exceedances in the area.
2. Evaluation of the Microscale Plan's Air Quality Modeling
While documentation in the plan is sparse in places, enough
information is provided to assess the adequacy of the approaches used.
The following summarizes EPA's evaluation of the microscale modeling.
The complete evaluation can be found in the TSD.
The rationale for the choice of monitoring sites to model with the
microscale approach is given in Appendix A to the plan. Past emission
inventory and modeling work for the Maricopa ara have identified
several fugitive dust source categories as being especially important
for PM-10 exceedances including urban lots, highway and other
construction activities, agricultural activities, and some industrial
sources. Study sites were chosen in areas of high emissions density:
South Phoenix for its mix of urban sources; 11 Salt River
for its proximity to industrial sources; West Chandler for its nearby
highway construction; and East Chandler for its mix of urban and
agricultural sources. The Gilbert and Maryvale sites were later added
because they recorded 24-hour exceedances during 1995. These sites are
characterized by nearby agricultural land and by park construction/
landscaping, respectively.
---------------------------------------------------------------------------
\11\ The South Phoenix site was not included in the microscale
plan because it did not record any 24-hour PM-10 exceedances in
1995. EPA's criterion for determining which sites were to be
analyzed in the microscale plan was whether the site had recorded
exceedances of the 24-hour NAAQS during 1995.
---------------------------------------------------------------------------
Together, all these sites present a representative cross-section of
the emission sources in the Maricopa area that are suspected of
contributing to PM-10 exceedances.
The microscale study took place throughout 1995. In addition to the
EPA's standard AP-42 emission methodologies and some other prior
special studies for particular source categories, the microscale study
included field surveys, aerial photography, examination of activity
logs, and interviews with source operators. This study resulted in a
substantially better emissions inventory data than is usually
available.
To help define the geographic domains to be included in the final
modeling, initial screening modeling was performed to determine the
distance beyond which sources have an insignificant impact at the
monitors. Concentrations observed at neighborhood scale monitors, and
information on the land uses that affect these, were used to develop
background concentrations for each portion of the modeling domain.
Background concentrations were then added to the results of the EPA-
recommended ISCST model to yield total predicted concentrations.
Episodes for modeling were chosen from among exceedance days that
occurred during the 1995 study. Because of the importance to the
microscale approach of an intensive emission inventory database, some
days had to be discarded for lack of adequate emission source activity
data.
The Sunday, April 9, 1995 high wind episode day was chosen for the
Gilbert, West Chandler, and Maryvale sites.12 For the Salt
River site, October 16, 1995
[[Page 31031]]
was selected since all the relevant sources were in operation, the
model validated well, and an October day was desirable since many of
the exceedances were in that month. Plan, Appendix A, pp. 7-18 to 7-19.
Multiple days could have been used and would have been desirable given
the seasonal shifts in the daily times of high concentration noted in
the plan. However, these varying concentrations were mainly dependent
on wind direction, and the chosen October 16, 1995 day exhibits fairly
high values in both morning and evening. Thus, the modeled phenomena
are similar enough to the other episodes that this single design day is
sufficient for the Salt River site.
---------------------------------------------------------------------------
\12\ For the Gilbert and Maryvale sites, the April 9, 1995
exceedance was the only 24-hour exceedance recorded in 1995. The
West Chandler site recorded a second exceedance on July 30, 1995.
Plan, p. 15. This exceedance also appears to be related to a high
wind event. Plan, Appendix A, p. 3-4.
---------------------------------------------------------------------------
Overall, the episodes modeled are representative of the conditions
under which exceedances of the 24-hour PM-10 NAAQS occur. Model
performance was generally good, especially for the Salt River site, and
well within what can be expected from the type of model used, a
Gaussian dispersion model.
The microscale plan's approach for demonstrating attainment within
each sub-area or modeling domain was proportional rollback. The basic
assumption in proportional rollback is that a given percentage
reduction in emissions yields the same percentage reduction in
concentration at the receptor. Every attainment demonstration for a
chemically-inert pollutant (that is, a pollutant that does not react in
the atmosphere) such as primary PM-10 is implicitly based on
proportional rollback, so the plan's approach is acceptable.
Air quality modeling should evaluate the effectiveness of controls
throughout the entire modeling domain. A control strategy sufficient
for attainment at the monitor or at the maximum modeled receptor might
not be sufficient at other receptor points within the domain where
source contributions could be different because of the varying
distances between the receptors and the sources. For the microscale
plan, this variation is probably not important for the Maryvale or Salt
River sub-areas, where a single source category at each site is so
dominant, but could be important for the Gilbert and West Chandler sub-
areas with their more equal mix of sources.13
---------------------------------------------------------------------------
\13\ The microscale plan does not demonstrate attainment at the
Gilbert and West Chandler sites; therefore, this point is moot. When
additional controls are analyzed for these sites, an array of points
within each modeling domain should be evaluated. Evaluation of
controls at a single point will not be adequate for an attainment
demonstration.
---------------------------------------------------------------------------
As the sub-areas are representative of the sources and conditions
that lead to exceedances, the air quality modeling in the microscale
plan is adequate for demonstrating attainment of the 24-hour PM-10
NAAQS for the Maryvale and Salt River sites within the context of the
microscale approach.
B. Evaluation of RACM/BACM
1. RACM/BACM Analysis
(a) Maryvale Site. The Maryvale PM-10 monitoring site is located
next to the Desert West Park which was under construction in early
1995. Plan, Appendix A, p. 4-2. The air quality modeling evaluation of
the Sunday, April 9, 1995 exceedance at the monitor showed that
windblown fugitive dust, all from the area cleared for the park (that
is, a disturbed cleared area), was the single largest contributor to
the exceedance. Plan, p. 18.
The microscale plan includes a list of potential control measures
for the disturbed cleared area category including wind fences, chemical
stabilizers, watering to maintain adequate soil moisture, and water to
maintain a crust. Plan, p. 22. This source category is also subject to
MCESD's Rule 310, Open Fugitive Dust Sources, which requires the
application of RACM to open sources of fugitive dust. RACM is defined
in the Rule 310 (section 221) and is detailed on the rule's dust
control plan checklist and handbook ``A Guide for Reducing Air
Pollution from Construction.'' See Plan, Appendix E, Letter, Joy Bell,
MCESD, to Joe Gibbs, ADEQ, May 6, 1997 (Bell letter).14
These measures include EPA's suggested RACM for this source
category.15 See General Preamble, Appendix C1.
---------------------------------------------------------------------------
\14\ The Maricopa County Board of Supervisors adopted on May 14,
1997 a resolution committing to implement improvements to the
administration of the fugitive dust control program and to foster
interagency cooperation to address fugitive dust. The microscale
plan included the draft resolution, and ADEQ transmitted the adopted
resolution to EPA on May 27, 1997. See letter from Nancy Wrona,
ADEQ, to John Kennedy, EPA.
\15\ Background concentrations at each of the monitoring sites
were substantial (80 to 90 g/m3). Analysis of the causes of
the high background levels was not part of the microscale protocol.
It is possible, therefore, that there are other significant sources
contributing to the exceedances at the monitors that have not been
identified because they only contribute to the background.
---------------------------------------------------------------------------
The microscale plan also identifies BACM enhancements, including
revising the dust control plan checklist to make permit holders aware
of the importance of preventing wind-blown dust even when areas are
inactive and the requirement to stabilize disturbed surfaces at all
times, and revising the handbook to encourage them to plan their
projects to minimize the amount of land disturbed at one time. Plan, p
27. These types of enhancements meet EPA's guidance for BACM by going
beyond existing RACM controls, expanding the use of RACM controls, and
emphasizing prevention over remediation.
(b) Salt River Site. The Salt River monitor is located on the
grounds of the City of Phoenix's Salt River Service Center Yard. The
site is surrounded by a number of industrial operations (including pre-
cast concrete manufacturing and sand and gravel operations), landfills
(the 19th Avenue Landfill superfund site and the 27th Avenue Landfill),
and other fugitive dust sources such as unpaved parking lots and roads.
Plan, Appendix A, pp. 6-3 and 6-4. The modeling showed that fugitive
dust from earth moving activities at 19th Avenue Landfill was the
single largest contributor to the modeled October 16, 1995 exceedance
and was the result of not watering to the depth of the cut during earth
moving operations. Plan, pp. 17 and 23. Fugitive dust from unpaved
parking lots, industrial haul roads and other unpaved roads also
contributed significantly to the exceedance. Plan, p. 17. See also
footnote 15 of this notice.
All these significant source categories are subject to the RACM
requirements in Rule 310. The microscale plan also includes a list of
controls for earth moving and unpaved parking lots,16 many
of which duplicate RACM required by Rule 310. Plan, p. 21. These
measures include EPA's suggested RACM for these source categories.
General Preamble, Appendix C1.
---------------------------------------------------------------------------
\16\ The identified control measures for unpaved parking lots
are also applicable to unpaved roads.
---------------------------------------------------------------------------
The microscale plan also identifies an enhancement to RACM for
earth moving operations. This enhancement requires watering to the
depth of the cut or other equivalent technique. Plan, p. 23. This type
of enhancement meets EPA's guidance for BACM by going beyond existing
RACM controls, expanding the use of RACM controls, and emphasizing
prevention over remediation. The microscale plan does not explicitly
identify BACM for unpaved parking lots, industrial haul roads, and
unpaved roads although clarifications to Rule 310 to make permit
holders aware of the importance of preventing wind-blown dust even when
areas are inactive and of the requirement to stabilize disturbed
surfaces at all times should improve control on these types of sources
when they are located at permitted facilities.
(c) Gilbert Site. The Gilbert monitoring site is located on the
grounds of the City of Gilbert's
[[Page 31032]]
wastewater treatment plant and has agriculture fields and aprons to its
north, paved and unpaved parking to the north and west, and a city park
to the south. Plan, Appendix A, pp. 4-5. The modeling showed that
windblown fugitive dust from agriculture aprons and unpaved parking
lots was the largest contributor to the Sunday, April 9, 1995
exceedance. Plan, p. 18. Fugitive dust from disturbed cleared areas was
also a significant contributor to the exceedance. Plan, p. 18. See also
footnote 15 of this notice. All these source categories are subject to
the RACM requirements in Rule 310.17 The RACM in Rule 310
include EPA's suggested RACM for these source category. General
Preamble, Appendix C1.
---------------------------------------------------------------------------
\17\ Application of Rule 310 to agricultural sources including
fields and aprons is affected by the provision in section 102
(incorporating A.R.S. 49-504.4) that the rule ``shall not be
construed so as to prevent normal farm cultural practices.''
Therefore, applicability of the rule to such sources depends on what
dust-generating operation is occurring at the source. In other
words, Rule 310 applies to some operations on agricultural fields
and aprons and not to others.
---------------------------------------------------------------------------
The BACM enhancement identified for these categories are
clarifications to the dust control requirements in Rule 310 and
improved enforcement of Rule 310. Plan, p. 23. These types of
enhancements meet EPA's guidance for BACM by going beyond existing RACM
controls, expanding the use of RACM controls, and emphasizing
prevention over remediation. The microscale plan also includes
development of a partnering process with the U.S. Natural Resources
Conservation Service (NRCS) to address fugitive dust from agricultural
sources (Plan, p. 36) and with the local jurisdictions in Maricopa
County to address unpaved parking (Plan, p 35); however, no potential
controls are identified for these sources, nor is there any analysis as
to why controls are not available.
(d) West Chandler Site. The West Chandler monitoring site is
located near the corner of Price and Frye Roads and is bordered on the
west by agriculture fields (which were idle on April 9, 1995) and the
right of way for Price Road/Freeway which was under construction in
early 1995. Plan, Appendix A, p. 4-4. The modeling showed that
windblown fugitive dust, mainly from agricultural fields and road
construction (disturbed cleared area), was the largest contributor to
the April 9, 1995 exceedance. Fugitive dust from vacant lands and
agricultural aprons was also a significant contributor. Plan, p. 19.
See also footnote 15 of this notice. All these source categories are
subject to the RACM requirements in Rule 310 (see footnote 17 of this
notice). These measures include EPA's suggested RACM for all these
source category except agricultural fields. General Preamble, Appendix
C1.
The BACM enhancements to RACM for these categories are similar to
those recommended for Gilbert and Maryvale. Plan, p. 28. These types of
enhancements meet EPA's guidance for BACM by going beyond existing RACM
controls, expanding the use of RACM controls, and emphasizing
prevention over remediation.
(e) PM-10 Precursors. CAA section 189(e) states that the control
requirements applicable under PM-10 plans for major stationary sources
of PM-10 are also applicable to major stationary sources of PM-10
precursors (such as NOX and SOX sources) except
where EPA determines that such sources do not contribute significantly
to PM-10 levels. General Preamble at 13541-13542. ``Significant'' is
not defined in the General Preamble, rather for moderate areas, the
determination was to be made on a case-by-case basis. General Preamble
at 13539. For serious areas, a ``significant'' source category is
defined as one that contributes 5 g/m3 or more of
PM-10 to a location of expected 24-hour violation. Addendum at 42001.
For this rulemaking only, EPA is proposing to apply the serious area
definition to both the RACT and BACT necessity determinations.
It is clear from the modeling that primary-emitted PM-10 (i.e.,
fugitive dust) is the only significant contributor to the 24-hour PM-10
exceedances at the four modeled sites. Based on this evidence, EPA is
proposing to determine under section 189(e) that sources of PM-10
precursors do not contribute significantly to PM-10 levels which exceed
the 24-hour standard at the Gilbert, West Chandler, Maryvale, and Salt
River monitors and therefore no RACM/BACM controls are necessary for
these sources. This proposed finding applies only to the microscale
plan and will need to be evaluated again for the full regional plan.
2. RACM/BACM Implementation
(a) MCESD Rules and Commitments. The primary conclusion of the air
quality modeling is that the 24-hour PM-10 exceedances at the four
evaluated sites are related solely to fugitive dust. The eight source
categories of fugitive dust that were identified as significant (that
is, had an impact of 5 g/m3 or more) at one or more
monitoring sites are regulated wholly or in part by MCESD's Rule 310
(Open Sources of Fugitive Dust). See footnote 17 of this notice. These
significant source categories are disturbed cleared area, earth moving,
unpaved parking lots, unpaved roads, industrial haul roads, vacant
land, agricultural fields, and agricultural aprons.
(i) Rule 310. Rule 310 was adopted by Maricopa County in 1988,
substantially revised in 1993, and revised again in 1994. The rule was
initially submitted to EPA in 1994 as part of the moderate area PM-10
plan for the Maricopa area, and EPA approved the rule on April 10, 1995
(60 FR 18010) in conjunction with its approval of the overall moderate
area plan. This plan's approval was subsequently vacated by the Ninth
Circuit in Ober. Although the court's opinion did not address the SIP
approvability of Rule 310, its disposition had the incidental effect of
also vacating EPA's approval of Rule 310.
In the 1994 proposed approval of the moderate area plan, EPA found
that Rule 310 met the CAA's enforceability requirements and proposed to
approve the rule except for a ``director's discretion''
provision.18 59 FR 38402 (July 28, 1994). Several comments
questioning the enforceability of Rule 310 were received on the
proposal but none changed EPA's conclusion that the rule was
enforceable. 60 FR 18018. Neither the rule nor EPA's finding that the
rule meets the SIP enforceability criteria has changed since that time.
Therefore EPA is reaffirming its previous finding that Rule 310 meets
the requirements of CAA sections 110(a)(2)(A) and 172(c)(6) for
enforceable emission limitations. As a result, EPA is proposing to
reapprove Rule 310 as an element of the Arizona SIP for the Maricopa
PM-10 nonattainment area.
---------------------------------------------------------------------------
\18\ This provision was subsequently deleted from the rule.
---------------------------------------------------------------------------
Implementation of Rule 310. Rule 310 requires the application of
reasonably available control measures to open sources of fugitive dust.
RACM is defined in the rule (section 221) and is detailed on the dust
control plan checklist and in the Rule 310 handbook ``A Guide for
Reducing Air Pollution from Construction.'' The microscale plan
includes revisions to the checklist and handbook to reflect BACM. Plan,
Appendix E, Bell letter. These revisions include making clear that the
dust control plan must be implemented throughout the life of the
project until all roads and disturbed areas are stabilized and that
watering is required to the depth of an earth moving cut.
Rule 310 also requires that an earth moving permit be obtained
prior to
[[Page 31033]]
engaging in any commercial, industrial or institutional earth moving or
dust generating operation that disturbs a total surface area of 0.10
acres or more.\19\ Rule 310, section 302 (dust generating operations--
permits required). A dust control plan must be submitted with the
permit application. Rule 310, section 303 (control plans). Earth moving
permits must be renewed every year. Rule 200 (Permit Requirements),
section 305.4. No permit is required for other fugitive dust sources
regulated by Rule 310 such as unpaved parking lots, unpaved roads,
vacant lots, agricultural fields, and agricultural aprons.
---------------------------------------------------------------------------
\19\ Maricopa County's interpretation of the prohibition in
A.R.S. 49-504.4 that county air pollution control agencies cannot
``prevent [] normal farm cultural practices which cause dust'' has
effectively exempted agricultural sources from the permit
requirements of Rule 310. Plan, p. 31.
---------------------------------------------------------------------------
To help permit applicants develop dust control plans, MCESD has
developed a general dust control plan or checklist that lists RACM by
category (e.g., earth moving, disturbed surface areas). Permit
applicants can simply check off the RACM they will use but must check
off at least one measure per category. Alternatively, applicants may
craft their own dust control plans provided they meet the requirements
of Rule 310. See Plan, p. 34 (revised dust control plan checklist).
Review of earth moving permit applications and dust control plans
as well as the inspection of permitted earth moving sites is done
primarily by the MCESD's Earthmoving/Burn Permit
Coordinator.20 Inspections are conducted for all projects
greater than 10 acres in size and smaller operations are inspected
based on several factors including the compliance history of the
contractor/developer or complaints. Some inspections are performed by
the Department's regional offices when time allows. Plan, Appendix B,
p. 2-5. MCESD inspectors also note earth moving operations when they
are out in the field and stop to check if the required permit is
posted. Plan, Appendix G, p. 18. Historically, stationary sources have
not been inspected for Rule 310 violations even when they have fugitive
dust sources subject to the rule.21 Plan, Appendix B, p. 2-
5.
---------------------------------------------------------------------------
\20\ During the fall and winter this Coordinator is also
responsible for implementing the County's residential wood burning
restriction rule. Given the demonstrated contribution of earth
moving sources to Maricopa area PM-10 exceedances, MCESD may want to
re-evaluate splitting the Coordinator's time between the fugitive
dust and no burn programs.
\21\ MCESD is addressing the permitting process for stationary
sources subject to dust control plan requirements in a work flow
review and analysis of the Department's permitting process.
Recommendations from this review (such as revised permitting
procedures) will be implemented in July, 1997. Plan, Appendix E,
Bell letter. Improved permitting of these sources should result in
better inspections.
---------------------------------------------------------------------------
MCESD only inspects sources that do not require permits (such as
vacant land and unpaved parking lots) on a complaint basis and has no
proactive inspection or compliance assurance program for these types of
sources. Plan, p. 12.
The microscale plan identifies a number of recommended changes to
improve implementation of Rule 310. MCESD has or will undertake a
number of internal program modifications to implement these
recommendations and will lead a regional program to foster interagency
cooperation to reduce particulate pollution.
Some of the internal program modifications the Department has
already made are revising a number of documents that support
implementation of Rule 310 including the dust control plan, the Rule
310 handbook, the guideline for earth moving inspection checklist, and
the standard operating procedures (SOP) for earth moving permit
application processing and site inspection. In addition, MCESD is
revising the SOP for air pollution inspection procedures.22
Plan, Appendix E, Bell letter. Other changes include updating staff
training on Rule 310 (target completion date: May 31, 1997), initiating
a weekend inspection program for Rule 310 sources (target date: May,
1997), and linking the earth moving permit, complaint, and enforcement
databases to improve access to information on permitted sources (target
completion date: February, 1998). Plan, Appendix E, Bell letter. A
complete description of MCESD's commitments can be found in the Plan,
Appendix E, Bell letter.
---------------------------------------------------------------------------
\22\ EPA recently complete a review of permit files at MCESD.
One of the focuses of this file review was to evaluate the effect of
the SOPs on the completeness and quality of inspections. The review
showed that the SOPs have resulted in more thorough and higher
quality inspections. Memorandum, Colleen McKaughan to Doug McDaniel,
``File Review at Maricopa County Environmental Services Department
April 7-10, 1997'' May 19, 1997 (found in the docket).
---------------------------------------------------------------------------
Regional Program. MCESD has also committed to a regional program to
foster interagency cooperation including designating a MCESD staff
person as a coordinator, holding Rule 310 workshops for cities and
contractors, creating material on Rule 310 for distributing to City/
County staff and contractors, continuing to conduct workshops in 1997
on studying and improving the current dust control program, expanding
public awareness programs for particulate pollution, and publicizing
MCESD's public complaint line number. The regional program will be
fully implemented in 1997. A complete description of MCESD's
commitments can be found in the Plan, Appendix E, Bell letter.
In total, MCESD's commitments clearly identify the actions required
and the deadlines for those actions and thus constitute enforceable
control measures under CAA sections 110(a)(2)(A) and 172(c)(6). EPA,
therefore, proposes to approve them as elements of the Arizona SIP.
Resources for Rule 310 Implementation. MCESD will continue to
implement Rule 310 through a program of reviewing and evaluating dust
control plans, inspection of sources with earthmoving permits, and
responding to complaints. The Earthmoving/Burn Permit Coordinator has
primary responsibility for reviewing dust control plans and inspections
and is aided in inspections by four dedicated stationary source
inspectors in the main office. In addition, MCESD has recently hired a
public involvement coordinator and an assistant to the Earthmoving/Burn
Permit Coordinator. Finally, the Department's Small Business Assistance
Program also assists in implementing Rule 310 through outreach and
compliance assistance. Plan, Appendix E, Bell letter.
Complaints are handled by the appropriate regional office. Each
regional office has one supervising inspector and two staff inspectors.
The regional offices also do earth moving inspections as time allows
during the summer months. These non-complaint inspections are limited
to permitted sites from 5 to 10 acres. Plan, Appendix B, pp. 2-4 and 2-
5.
In all, there are 1.75 full time equivalent (FTE) positions working
directly on Rule 310 implementation, plus the Department has 19
inspectors, aides, engineers, and supervisors available to perform
field observations and respond to complaints. Plan, Appendix E, Bell
letter. This level of staffing (when combined with the support from the
rest of the Department's inspection staff) is sufficient to ensure
implementation of Rule 310 at the level assumed and committed to in the
microscale plan, that is, a reasonable level of implementation on
permitted sources but minimal implementation on nonpermitted
sources.23
---------------------------------------------------------------------------
\23\ The microscale plan only assumes emission reductions from
sources subject to permitting (e.g., earth moving, disturbed cleared
areas). No reductions are assumed for nonpermitted sources (e.g.,
vacant lots, unpaved parking). See Plan, pp. 37-40.
---------------------------------------------------------------------------
[[Page 31034]]
(ii) Rules 311 and 316. Individual point sources (e.g., several
concrete manufacturers and sand and gravel operations) whose emissions
are accounted for within several of the source categories at the Salt
River site are also covered by MCESD's Rule 311 (Particulate Matter
from Process Industries) and Rule 316 (Nonmetallic Mineral Mining and
Processing). These rules were approved by EPA as RACT for PM-10 sources
as part of the approval of the moderate area plan. 60 FR 18009. While
not at issue in the litigation regarding that plan's approval, EPA's
approval of these rules was also incidently vacated by the Ober
decision. EPA, therefore, will be restoring its approval of these rules
in its final action on this proposal.
(b) City Resolutions. The microscale plan includes resolutions
adopted by the Cities of Phoenix, Tempe, Chandler, Glendale,
Scottsdale, and Mesa and the Town of Gilbert (collectively, city or the
cities). Plan, Appendix E, ``Resolutions Adopted by Various Cities and
Towns within Maricopa County'' (resolutions). The resolutions commit
each city to participate in a regional program led by MCESD to foster
interagency cooperation to reduce particulate pollution. This
participation requires the city to (1) designate a staff person to
coordinate the city's participation in the regional dust control
program, (2) participate in workshops (to be held by MCESD) to study
current dust control programs and to evaluate options for additional
efforts, (3) distribute MCESD information on dust control to grading
and certain building permit applicants, (4) ensure appropriate city
personnel receive training on Rule 310 requirements, and (5) distribute
information on particulate pollution to the public. The resolutions do
not commit the cities to adopt any additional dust control
requirements.
The cities will undertake these actions using current staffing and
funding. Plan, p. 35 and Appendix E, resolutions. Because these actions
are easily integrated into on-going city activities, these staffing and
funding levels are adequate to implement the commitments. MCESD has
complemented the cities' efforts by committing to designate a staff
person as the regional program coordinator, to hold workshops, develop
material for distribution, and provide training on Rule 310. Plan,
Appendix E, Bell letter.
The commitment to address fugitive dust is an important additional
step by the cities to help solve Maricopa's PM-10 problem in the long
term.24 The air quality modeling clearly shows that fugitive
dust from nonpermitted sources such as vacant lands, unpaved parking
lots, and unpaved roads are significant contributors to exceedances.
Given the size of the Maricopa PM-10 nonattainment area and MCESD's
limited resources, the cities and towns will need to take a more active
role in reducing fugitive dust from these nonpermitted sources.
---------------------------------------------------------------------------
\24\ Many of the cities and towns in Maricopa County have
already committed to undertake other PM-10 control measures such as
paving unpaved roads. See MAG 1991 Particulate Plan.
---------------------------------------------------------------------------
The cities' resolutions clearly identify the actions required and
the deadlines for those actions and thus constitute enforceable
commitments. As such, EPA proposes to approve them into the Arizona SIP
for the Maricopa PM-10 nonattainment area.
(c) Agricultural Sources. As discussed previously, the air quality
modeling demonstrated that control of fugitive dust from agricultural
fields and field aprons is necessary for attainment of the 24-hour PM-
10 standard at the Gilbert and West Chandler sites. Rule 310, while
nominally applicable to agricultural sources, is not in general
enforced against them. Plan, p. 31. See also footnote 17 of this
notice. The microscale plan contains no controls for these source
categories but does include an agreement by ADEQ, MCESD, and the
federal Natural Resources Conservation Services (NRCS) to develop a
protocol to address fugitive dust on agricultural land and refine
roles, objectives and schedule. Plan, p. 36 and Appendix E, ``Agreement
of ADEQ, U.S. NRCS, and MCESD'' (NRCS agreement).
EPA appreciates the agreement of the three agencies to develop a
protocol to address fugitive dust from agricultural sources and fully
supports this effort. However, given the impact of these sources on PM-
10 levels in the Maricopa area, it is important that the protocol and
the work that follows it are focused on getting appropriate RACM and
BACM measures in place by the applicable deadlines.
(d) Proposed Finding on RACM/BACM Implementation. There are eight
source categories of fugitive dust identified in the microscale plan as
significant at one or more monitoring sites: disturbed cleared area,
earth moving, unpaved parking lots, unpaved roads, industrial haul
roads, vacant land, agricultural field aprons, and agricultural
fields.25 Plan, pp. 17-19. These sources divide into three
categories. In the first category are sources subject to permitting:
disturbed cleared areas, earth moving, and industrial haul
roads.26 In the second category are sources that are not
subject to permitting (i.e., nonpermitted sources): unpaved parking
lots, unpaved roads, and vacant land. Finally, in the third category
are the two sources that are essentially unregulated by Rule 310:
agricultural fields and agricultural aprons.
---------------------------------------------------------------------------
\25\ As noted previously (footnote 15), there may be other
significant sources impacting the monitors that were not identified
in the microscale modeling because they formed part of the
background concentration.
\26\ Haul roads are considered permitted sources in the
microscale plan because, at the Salt River site where this category
was significant, the haul roads are located on permitted sources.
---------------------------------------------------------------------------
As discussed above, MCESD has an adequate implementation strategy
for dealing with permitted sources including review and approval of
dust control plans and proactive inspections and has sufficient
resources to carry out that strategy. The Department adopted Rule 310
in 1994 and is already implementing and improving the program. Plan,
pp. 7-13 and 32-33. The BACM improvements to the Rule 310 program and
the other commitments in the microscale plan will all be fully
implemented within one year of submittal of the final plan, with many
being implemented within one or two months. Plan, pp. 32-33. EPA,
therefore, is proposing to find that the microscale plan assures
implementation of RACM as soon as possible and BACM by December 10,
2000 as required by CAA sections 189(a)(1)(C) and 189(b)(1)(B) for the
significant source categories of: disturbed cleared areas, earth
moving, and industrial haul roads. EPA is proposing to approve the
RACM/BACM demonstrations for these source categories.
For nonpermitted sources, MCESD seeks compliance with Rule 310 only
when complaints are received. MCESD has adopted RACM controls for these
sources in Rule 310 and is committed along with the seven cities to
evaluate options to reduce particulate from vacant lands, unpaved
roads, and unpaved parking areas. Plan, Appendix E, Bell Letter. The
microscale plan, however, contains no commitments to assure RACM/BACM
will be implemented for these sources at a meaningful level nor any
analysis as to why RACM or BACM implementation on these sources is
infeasible. As a result, the microscale plan does not claim any credit
in the attainment demonstrations for these nonpermitted sources. Plan,
pp. 37-40. EPA, therefore, is proposing to find that the microscale
plan does not assure implementation of
[[Page 31035]]
either RACM or BACM as required by CAA sections 189(a)(1)(C) and
189(b)(1)(B) and to disapprove the RACM/BACM demonstrations for the
unpaved parking lots, unpaved roads, and vacant land source categories.
As discussed previously, there are currently no effective controls
on agricultural sources in the Maricopa area. The microscale plan
provides for the development of a partnership to identify appropriate
controls but does not contain any actual controls nor is there any
analysis as to why RACM/BACM implementation on these sources is
infeasible. EPA is, therefore, proposing to find that the microscale
plan does not assure implementation of either RACM or BACM as required
by CAA sections 189(a)(1)(C) and 189(b)(1)(B) and to disapprove the
RACM/BACM demonstrations for these sources.
These proposed findings are applicable only to the microscale plan
and thus, if finalized, will not constitute EPA's final decision as to
the State's full compliance with the requirements of CAA sections
189(a)(1)(C) and 189(b)(1)(B) for RACM and BACM for the eight source
categories. The State will need to re-evaluate appropriate RACM and
BACM for these sources in the full regional plan.
C. Evaluation of Attainment and RFP Demonstrations
1. Salt River Site
As discussed above, attainment of the 24-hour PM-10 standard at the
Salt River site requires additional controls for earth moving
activities, specifically watering to the depth of the cut or other
equivalent techniques, in addition to the existing control provided by
Rule 310. Plan, p. 37. These earth moving activities are subject to
permitting under Rule 310. MCESD will revise its dust control plan
checklist to clarify the earth moving requirement in May, 1997, and
will begin including the requirement in all new earth moving permits
and permit renewals by June 1, 1997. Plan, Appendix E, Bell letter.
Permit renewals are required annually, thus full implementation will
occur within one year of the submittal of the final plan. Plan, p. 38.
Attainment is predicted based on acceptable air quality modeling.
EPA will be restoring its approval of Rules 311 and 316. EPA is also
proposing to reapprove Rule 310 and to approve the additional controls
assumed in the attainment demonstration. Finally, EPA is also proposing
to find that MCESD has adequate resources, personnel, and authority to
assure implementation of the measures required for attainment at this
site. EPA is, therefore, proposing to approve the attainment
demonstration at the Salt River monitor pursuant to CAA sections
189(a)(1)(B) and 189(b)(1)(A).
Reasonable further progress is defined in CAA section 171(1) as
``such annual incremental reductions in emissions of the relevant air
pollutant as * * * may be reasonably be required by the Administrator
for the purposes of ensuring attainment of the applicable [NAAQS].''
Because attainment will occur within one year of final plan submittal,
the RFP and attainment demonstrations at this monitor are the same;
that is the annual increment needed for progress toward attainment is
the same as the emission reduction needed for attainment. Therefore,
EPA is proposing to approve the RFP demonstration at this monitor
pursuant to CAA section 189(c).
2. The Maryvale Site
Attainment of the 24-hour PM-10 standard at the Maryvale site
requires stabilization of disturbed cleared areas at all times. Plan,
p. 38. Disturbed cleared areas is a source category subject to
permitting under Rule 310. MCESD has revised its dust control plan
checklist for Rule 310 to clarify the requirement to stabilize all
disturbed areas at all times and will begin including the requirement
in all new earth moving permits and permit renewals by June 1, 1997.
Plan, Appendix E, Bell letter. Permit renewals are required annually,
thus full implementation and attainment will occur within one year of
the submittal of the final plan. Plan, p. 38.
Attainment is predicted based on acceptable air quality modeling.
EPA is proposing to reapprove Rule 310 and to approve the additional
controls assumed in the attainment demonstration. Finally, EPA is
proposing to find that MCESD has adequate resources, personnel, and
authority to assure implementation of the measures to the extent
required for attainment at this site. EPA is, therefore, proposing to
approve the attainment demonstration at the Maryvale monitor pursuant
to CAA sections 189(a)(1)(B) and 189(b)(1)(A).
Because attainment will occur within one year of final plan
submittal, the RFP and attainment demonstrations at this monitor are
essentially the same; that is the annual increment needed for progress
toward attainment is the same as the emission reductions needed for
attainment. Therefore, EPA is proposing to approve the RFP
demonstration at this monitor pursuant to CAA section 189(c).
3. The Gilbert Site
The microscale plan does not demonstrate attainment or RFP at the
Gilbert site because of uncontrolled fugitive dust emissions from
agricultural aprons and unpaved parking lots. Plan, p. 38. As noted
before, the microscale plan does include strategies to evaluate
controls on these sources but, at this time, does not assure
implementation of controls for them. EPA is, therefore, proposing to
disapprove the attainment and RFP demonstrations for this site.
4. The West Chandler Site
The microscale plan does not demonstrate attainment or RFP for the
West Chandler site because of uncontrolled fugitive dust emissions from
agricultural fields and aprons and vacant land. Plan, p. 39. As noted
before, the microscale plan does include strategies to evaluate
controls on these sources but, at this time, does not assure
implementation of controls for them. EPA is, therefore, proposing to
disapprove the attainment and RFP demonstrations for this site.
These proposed approvals and disapprovals are applicable only to
the microscale plan and thus, if finalized, will not constitute EPA's
final decision as to the State's full compliance with the requirements
of CAA sections 189(a)(1)(B), 189(b)(1)(A) and 189(c)(1) for attainment
and RFP demonstrations at the Salt River, Maryvale, Gilbert and West
Chandler monitoring sites. Because regional factors may influence
attainment at these sites, the State will need to re-evaluate modeling
at all four sites as part of the full regional plan.
D. General SIP Requirements
1. Section 110(l) Finding
CAA section 110(l) states that the ``Administrator shall not
approve a revision of a plan if the revision would interfere with any
applicable requirement concerning attainment and reasonable further
progress * * * or any other applicable requirement of this Act.''
Pursuant to section 110(l) of the Act, EPA proposes to find that
its proposed partial approval of the microscale plan does not interfere
with any other requirements of the Act applicable to the Maricopa PM-10
nonattainment area including the requirements for attainment and RFP.
In fact, the control measures and commitments in the plan are essential
elements in the demonstrations of attainment and RFP for the area for
the 24-hour PM-10
[[Page 31036]]
NAAQS and partially meet the statutory requirement for the adoption and
implementation of RACM and BACM.
2. Adequate Personnel, Funding, and Authority
Section 110(a)(2)(E)(i) of the Clean Air Act requires that
implementation plans provide necessary assurances that the state (or
the general purpose local government) will have adequate personnel,
funding and authority under state law. Requirements for legal authority
are further defined in 40 CFR part 51, subpart L (51.230-232) and for
resources in 40 CFR 51.280. States and responsible local agencies must
demonstrate that they have the legal authority to adopt and enforce
provisions of the SIP and to obtain information necessary to determine
compliance. SIPs must also describe the resources that are available or
will be available to the State and local agencies to carry out the
plan, both at the time of submittal and during the 5-year period
following submittal.
Adequate Personnel and Funding. For Rule 310, the microscale plan
reflects MCESD's current bifurcated implementation strategy of
proactive compliance and enforcement on permitted sources and reactive
enforcement on nonpermitted sources. This implementation strategy is
assumed in the attainment demonstrations in which emission reductions
are assumed only from permitted sources and not from nonpermitted
sources. Plan, pp. 37-40. MCESD's available resources (both personnel
and funding) for carrying out this bifurcated strategy for Rule 310 and
its other commitments are discussed above and are adequate. MCESD
expects to maintain this level of resource commitment over the next
five years of plan implementation. Plan, p. 33.
The cities' resources for implementing their respective commitments
are also discussed above and are adequate. Each agency is expected to
maintain this level of resource commitment over the next five years of
plan implementation. Plan, pp. 35 and 36.
Adequate Legal Authority. The primary implementing agency of the
controls in the microscale plan is the County of Maricopa through its
Environmental Services Department. A.R.S. 49-479 provides that the
board of supervisors ``shall adopt such rules as it determines are
necessary and feasible to control release into the atmosphere of air
contaminants. * * *'' A.R.S. 49-476.01 provides the County control
officer the authority to require sources to monitor, sample, or
otherwise quantify their emissions and the board of supervisors the
authority to adopt rules for source monitoring, sampling, etc. These
sections provide the County and MCESD with sufficient authority under
State law to adopt and enforce the proposed control measures and to
obtain the information necessary to determine compliance.
Legal authority for the cities to adopt and implement their
resolutions are described in the microscale plan on pp. 35-36 and
appears to be adequate.
These proposed findings regarding adequate authority and resources
are applicable only to the control strategy and commitments as
submitted in the microscale plan.
3. Description of Enforcement Methods
Section 110(a)(2)(C) requires SIPs to include a program to provide
for the enforcement of SIP measures. The implementing regulation for
this section is found at 40 CFR 51.111(a) and requires control
strategies to include a description of enforcement methods including
(1) procedures for monitoring compliance with each of the selected
control measures, (2) procedures for handling violations, and (3) the
designation of the agency responsible for enforcement.
Procedures for monitoring compliance (i.e., the inspection
strategy) with Rule 310 are discussed in the section on MCESD
commitments above. MCESD is the designated agency for enforcing Rule
310. See legal authority section above.
MCESD has developed an Air Enforcement Policy (April 4, 1997). A
summary of this strategy can be found in the microscale plan, Appendix
E, Bell letter. Currently, the Department issues Notices of Violations
(NOVs) whenever violations of rules are observed (Plan, p. 12) and will
continue to do so. Orders of abatement will be issued after NOVs when
compliance is not attainable within a reasonable time frame. Additional
enforcement actions may be initiated based on several factors including
actual or significant potential harm or willful noncompliance. The
additional actions include filing criminal or civil complaints.
Appropriate monetary penalties will be sought for criminal or civil
complaints and the Department encourages Environmental Community Action
Projects as part of settlements. Plan, Appendix E, Bell letter.
EPA has also encouraged MCESD to take more enforcement actions with
monetary penalties in order to make clear to the regulated community
that compliance with Rule 310 should be a priority and to develop a
system for tracking the number of NOVs and monetary penalties. See
letter, Frances Wicher, EPA, to Joe Gibbs, ADEQ, April 30, 1997 (found
in the Plan, Appendix D). In all, the Department's Air Enforcement
Policy is adequate to meet the requirements of 40 CFR 51.111(a) and CAA
section 110(a)(2)(C).
III. Summary of Proposed Action
A. Proposed Approvals and Disapprovals
For the reasons discussed above, EPA is proposing to approve:
(1) Under sections 172(c)(1), 189(a)(1)(C) and 189(b)(1)(B), the
provisions for implementing RACM and BACM for the significant source
categories of disturbed cleared areas, earth moving, and industrial
haul roads; and
(2) Under sections 189(a)(1)(B), 189(b)(1)(A), and 189(c), the
attainment and RFP demonstrations for the Maryvale and Salt River
sites.
For the reasons discussed above, EPA is proposing to disapprove:
(1) Under sections 172(c)(1), 189(a)(1)(C) and 189(b)(1)(B), the
provisions for implementing RACM and BACM for the significant source
categories of agricultural fields, agricultural aprons, vacant lands,
unpaved parking lots, and unpaved roads; and
(2) Under sections 189(a)(1)(B), 189(b)(1)(A), and 189(c)(1), the
attainment and RFP demonstrations at the West Chandler and Gilbert
sites.
Finally, EPA is proposing to find that the microscale plan (1)
provides the necessary assurances that the state and local agencies
have adequate personnel, funding and authority under state law to carry
out the submitted microscale plan, and (2) includes an adequate
enforcement program, as required by CAA sections 110(a)(2)(E)(i) and
110(a)(2)(C).
B. Consequences of the Proposed Disapprovals
As noted before, EPA required submittal of a microscale plan
meeting both the moderate and serious area requirements for the 24-hour
PM-10 standard by May 9, 1997 and a full regional plan meeting those
requirements for both the 24-hour and annual standards by December 10,
1997. The microscale and regional plans taken together would satisfy
both the moderate area requirements for the 24-hour standard mandated
by the Ninth Circuit in Ober and the serious area planning requirements
for both standards. The subject of this proposed action is the
microscale plan only; the full regional plan is not due until late
1997. It is, therefore, premature to
[[Page 31037]]
determine if the microscale plan, in and of itself, fully complies with
the Clean Air Act requirements for moderate and serious PM-10
nonattainment areas. Such a determination is not possible until the
regional plan is submitted and reviewed.
Because the microscale plan taken alone is not intended to fully
comply with the RACM/BACM implementation, reasonable further progress
and attainment demonstration requirements of the Clean Air Act, final
disapprovals of portions of the microscale plan would not trigger
sanctions under CAA section 179(a). CAA section 179(a) requires the
imposition of one of the sanctions in section 179(b) within 18 months
of a disapproval if EPA ``disapproves a [State] submission * * * based
on the submission's failure to meet one or more of the elements
required by [the CAA].'' Because the purpose of the microscale plan was
to, in effect, provide a down payment towards meeting certain
requirements of the Act, EPA is not, at this time, proposing to find
that the State has failed to meet any of the applicable elements
required by the CAA as contemplated by section 179(a).
EPA is subject to the terms of a consent decree approved by the
U.S. District Court for the District of Arizona on March 25, 1997. Ober
v. Browner, No. CIV 94-1318 PHX PGR. The consent decree obligates EPA
to propose a federal implementation plan (FIP) for PM-10 in the
Maricopa nonattainment area by March 20, 1998 and finalize that FIP by
July 18, 1998 27 if the Agency disapproves all or part of
the microscale plan. Therefore, if EPA finalizes the proposed
disapprovals described above, EPA will have an obligation to promulgate
a regional moderate area PM-10 FIP that addresses the statutory
requirements for attainment, RACM and RFP. Under the consent decree,
the scope of this FIP obligation is reduced to the extent that EPA
approves by July 18, 1998 SIP provisions meeting the statutory
requirements for RACM, RFP and attainment for moderate PM-10
nonattainment areas.
---------------------------------------------------------------------------
\27\ The FIP deadlines each advance 2 months if EPA fails to act
on the microscale plan by July 18, 1997.
---------------------------------------------------------------------------
EPA believes, as is expressed in CAA section 101(a), that air
pollution control is primarily the responsibility of states and local
jurisdictions. Therefore, the Agency will work with the State of
Arizona and the local agencies and jurisdictions responsible for PM-10
planning and control in Maricopa County to develop SIP provisions that
can reduce the scope of, or eliminate, any potential FIP. Considerable
work is already underway or planned in the area to address the PM-10
problem. As noted before, the full serious area regional PM-10 plan is
due December 10, 1997. In addition, the microscale plan contains two
initiatives, MCESD's regional program to address controls on
nonpermitted sources and the ADEQ/MCESD/NRCS agreement to address
fugitive dust from agricultural sources, that are targeted at
significant but currently uncontrolled sources of PM-10.
IV. Administrative Requirements
A. Executive Order 12866
This action has been classified as a Table 3 action for signature
by the Regional Administrator under the procedures published in the
Federal Register on January 19, 1989 (54 FR 2214-2225), as revised by a
July 10, 1995 memorandum from Mary Nichols, Assistant Administrator for
Air and Radiation. The Office of Management and Budget (OMB) has
exempted this regulatory action from E.O. 12866 review.
B. Regulatory Flexibility Act
Under the Regulatory Flexibility Act, 5 U.S.C. Sec. 600 et seq.,
EPA must prepare a regulatory flexibility analysis assessing the impact
of any proposed or final rule on small entities. 5 U.S.C. Secs. 603 and
604. Alternatively, EPA may certify that the rule will not have a
significant impact on a substantial number of small entities. Small
entities include small businesses, small not-for-profit enterprises,
and government entities with jurisdiction over populations of less than
50,000.
SIP approvals under sections 110 and 301, and subchapter I, part D
of the CAA do not create any new requirements but simply act on
requirements that the State is already imposing. Therefore, because the
Federal SIP approval does not impose any new requirements, I certify
that it does not have a significant impact on any small entities
affected. Moreover, due to the nature of the Federal-State relationship
under the CAA, preparation of a flexibility analysis would constitute
Federal inquiry into the economic reasonableness of State action. The
Clean Air Act forbids EPA to base its action concerning SIPs on such
grounds. Union Electric Co. v. U.S. EPA, 427 U.S. 246, 255-66 (1976);
42 U.S.C. Sec. 7410(a)(2).
C. Unfunded Mandates
Under section 202 of the Unfunded Mandates Reform Act of 1995
(``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA
must prepare a budgetary impact statement to accompany any proposed or
final rule that includes a Federal mandate that may result in estimated
costs to State, local, or tribal governments in the aggregate; or to
private sector, of $100 million or more. Under section 205, EPA must
select the most cost-effective and least burdensome alternative that
achieves the objectives of the rule and is consistent with statutory
requirements. Section 203 requires EPA to establish a plan for
informing and advising any small governments that may be significantly
or uniquely impacted by the rule.
EPA has determined that the approval/disapproval action proposed
does not include a Federal mandate that may result in estimated costs
of $100 million or more to either State, local, or tribal governments
in the aggregate, or to the private sector. This Federal action
approves pre-existing requirements under State or local law, and
imposes no new Federal requirements. Accordingly, no additional costs
to State, local, or tribal governments, or to the private sector,
result from this action.
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Particulate
matter, Incorporation by reference.
Authority: 42 U.S.C. 7401.
Dated: May 29, 1997.
Felicia Marcus,
Regional Administrator.
[FR Doc. 97-14848 Filed 6-5-97; 8:45 am]
BILLING CODE 6560-50-P