[Federal Register Volume 80, Number 150 (Wednesday, August 5, 2015)]
[Rules and Regulations]
[Pages 46494-46508]
[FR Doc No: 2015-19090]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R03-OAR-2014-0910; FRL-9931-80-Region 3]

Approval and Promulgation of Air Quality Implementation Plans;
Pennsylvania; Infrastructure Requirements for the 2008 Ozone and 2010
Sulfur Dioxide National Ambient Air Quality Standards

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is approving
portions of two State Implementation Plan (SIP) revisions submitted by
the Commonwealth of Pennsylvania through the Pennsylvania Department of
Environmental Protection (PADEP) pursuant to the Clean Air Act (CAA).
Whenever new or revised National Ambient Air Quality Standards (NAAQS)
are promulgated, the CAA requires states to submit a plan for the
implementation, maintenance, and enforcement of such NAAQS. The plan is
required to address basic program elements, including but not limited
to regulatory structure, monitoring, modeling, legal authority, and
adequate resources necessary to assure implementation, maintenance, and
enforcement of the NAAQS. These elements are referred to as
infrastructure requirements. PADEP made submittals addressing the
infrastructure requirements for the 2008 ozone NAAQS and the 2010
sulfur dioxide (SO2) primary NAAQS.

DATES: This final rule is effective on September 4, 2015.

ADDRESSES: EPA has established a docket for this action under Docket ID
Number EPA-R03-OAR-2014-0910. All documents in the docket are listed in
the www.regulations.gov Web site. Although listed in the electronic
docket, some information is not publicly available, i.e., confidential
business information (CBI) or other information whose disclosure is
restricted by statute. Certain other material, such as copyrighted
material, is not placed on the Internet and will be publicly available
only in hard copy form. Publicly available docket materials are
available either electronically through www.regulations.gov or in hard
copy for public inspection during normal business hours at the Air
Protection Division, U.S. Environmental Protection Agency, Region III,
1650 Arch Street, Philadelphia, Pennsylvania 19103. Copies of the State
submittal are available at the Pennsylvania Department of Environmental
Protection, Bureau of Air Quality Control, P. O. Box 8468, 400 Market
Street, Harrisburg, Pennsylvania 17105.

FOR FURTHER INFORMATION CONTACT: Ruth Knapp,<PHONE_NUMBER>, or by
email at<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

I. Summary of SIP Revision

    On March 27, 2008 (73 FR 16436), EPA promulgated a revised ozone
NAAQS based on 8-hour average concentrations. EPA revised the level of
the 8-hour ozone NAAQS from 0.08 parts per million (ppm) to 0.075 ppm.
On June 22, 2010 (75 FR 35520), EPA promulgated a 1-hour primary
SO2 NAAQS at a level of 75 parts per billion (ppb), based on
a 3-year average of the annual 99th percentile of 1-hour daily maximum
concentrations. Pursuant to section 110(a)(1) of the CAA, states are
required to submit SIPs meeting the applicable requirements of section
110(a)(2) within three years after promulgation of a new or revised
NAAQS or within such shorter period as EPA may prescribe.
    On July 15, 2014, the Commonwealth of Pennsylvania, through the
PADEP, submitted SIP revisions that address the infrastructure elements
specified in section 110(a)(2) of the CAA necessary to implement,
maintain, and enforce the 2008 ozone NAAQS and the 2010 SO2
NAAQS. On February 6, 2015 (80 FR 6672), EPA published a notice of
proposed rulemaking (NPR) for Pennsylvania proposing approval of
portions of both SIP revisions as well as portions of SIP submittals
for other NAAQS.\1\ In the NPR, EPA proposed approval of Pennsylvania's
submissions addressing the following infrastructure elements: Section
110(a)(2)(A), (B), (C), (D)(i)(II) (prevention of significant
deterioration), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M).
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    \1\ On July 15, 2014, PADEP also submitted SIP revisions
addressing the infrastructure requirements for the 2010 nitrogen
dioxide (NO2) NAAQS and the 2012 fine particulate matter
(PM2.5) NAAQS. In the February 6, 2015 NPR, EPA also
proposed approval of portions of these infrastructure SIPs. Because
EPA did not receive adverse comments applicable to Pennsylvania's
infrastructure SIPs for the 2010 NO2 NAAQS or the 2012
PM2.5 NAAQS or applicable to EPA's proposed approval of
those specific SIPs, EPA took final action to approve portions of
the infrastructure SIPs for the 2010 NO2 NAAQS and 2012
PM2.5 NAAQS on May 8, 2015. 80 FR 26461. Thus, this final
action only addresses the July 15, 2014 infrastructure SIPs PADEP
submitted addressing the 2008 ozone NAAQS and the 2010
SO2 NAAQS.
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    Pennsylvania's July 15, 2014 infrastructure SIP submittals for the
2008 ozone NAAQS and the 2010 SO2 NAAQS did not contain any
provisions addressing section 110(a)(2)(I) which pertains to the
nonattainment requirements of part D, Title I of the CAA, because this
element is not required to be submitted by the 3-year submission
deadline of section 110(a)(1) and will be addressed in a separate
process. In addition, Pennsylvania's July 15, 2014 infrastructure SIP
submittals for the 2008 ozone NAAQS and the 2010 SO2 NAAQS
did not contain any provisions addressing CAA section
110(a)(2)(D)(i)(I), and therefore EPA's February 6, 2015 NPR did not
propose any action on the SIP submittals for section 110(a)(2)(D)(i)(I)
for either SIP submittal. Thus, this rulemaking action likewise does
not include action on CAA section 110(a)(2)(D)(i)(I) for either the
2008 ozone NAAQS or the 2010 SO2 NAAQS because PADEP's July
15, 2014 infrastructure SIP submittals did not include provisions for
this element. Finally, at this time, EPA is not taking action on
section 110(a)(2)(D)(i)(II) (which addresses visibility protection) for
the 2008 ozone or 2010 SO2 NAAQS as explained in the NPR.
Although Pennsylvania's July 15, 2014 infrastructure SIP submittals for
the 2008 ozone NAAQS and the 2010 SO2 NAAQS referred to
Pennsylvania's regional haze SIP to address section 110(a)(2)(D)(i)(II)
for visibility protection, EPA intends to take later, separate action
on Pennsylvania's SIP submittals for these elements as explained in the
NPR and the Technical Support Document (TSD) which accompanied the NPR.
    The rationale supporting EPA's proposed rulemaking action approving
portions of the July 15, 2014 infrastructure SIP submittals for the
2008 ozone and 2010 SO2 NAAQS, including the scope of
infrastructure SIPs in general, is explained in the NPR and the TSD
accompanying the NPR and will not be restated here. The NPR and TSD are
available in the docket for this rulemaking at www.regulations.gov,
Docket ID Number EPA-R03-OAR-

2014-0910.\2\ EPA received public comments on the NPR. Summaries of the
comments as well as EPA's responses are in section II of this
rulemaking notice. EPA's responses provide further explanation and
rationale where appropriate to support the final action approving
portions of the July 15, 2014 infrastructure SIPs.
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    \2\ EPA's final rulemaking action on Pennsylvania's
infrastructure SIP revisions for the 2010 NO2 NAAQS and
the 2012 PM2.5 NAAQS can also be found in this docket
with Docket ID Number EPA-R03-OAR-2014-0910.
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II. Public Comments and EPA's Responses

    EPA received substantive comments from two commenters, the State of
New Jersey Department of Environmental Protection (NJDEP) and the
Sierra Club, on the February 6, 2015 proposed rulemaking action on
Pennsylvania's 2008 ozone and 2010 SO2 infrastructure SIP
revisions. The Sierra Club's comments on the NPR include general
comments on infrastructure SIP requirements for emission limitations
and specific comments on emission limitations to address the 2010
SO2 NAAQS and the 2008 ozone NAAQS. A full set of all
comments is provided in the docket for today's final rulemaking action.

A. NJDEP

    Comment: NJDEP asserts that Pennsylvania's infrastructure SIP is
deficient because it does not include any information relating to
Pennsylvania's ``good neighbor'' obligation to address CAA section
110(a)(2)(D).\3\ NJDEP asserts the ability of downwind states including
New Jersey to attain the 2008 ozone NAAQS is substantially impacted by
interstate transport of pollution from Pennsylvania. NJDEP asserts
recent EPA modeling for the 2008 ozone NAAQS demonstrates Pennsylvania
significantly contributes to ozone nonattainment areas in New Jersey
and other states. New Jersey further asserts that EPA must ``make a
finding that Pennsylvania has failed to submit a SIP that complies with
Section 110(a)(2)(D) of the Clean Air Act'' because Pennsylvania did
not make a submission to address 110(a)(2)(D).
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    \3\ EPA believes NJDEP refers specifically to CAA section
110(a)(2)(D)(i)(I) which addresses interstate transport of pollution
and not to section 110(a)(2)(D)(i)(II) which addresses visibility
protection and prevention of significant deterioration.
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    Response: In this rulemaking EPA is not taking any final action
with respect to the provisions in section 110(a)(2)(D)(i)(I)--the
portion of the good neighbor provision which addresses emissions that
significantly contribute to nonattainment or interfere with maintenance
of the NAAQS in another state. In its July 15, 2014 infrastructure SIP
revisions for several NAAQS, the Commonwealth of Pennsylvania did not
include any provisions in its SIP revision submittals to address the
requirements of section 110(a)(2)(D)(i)(I). In the NPR, EPA did not
propose to take any action with respect to Pennsylvania's obligations
pursuant to section 110(a)(2)(D)(i)(I) for the July 15, 2014
infrastructure SIP submittals and is not, in this rulemaking action,
taking any final action on the 110(a)(2)(D)(i)(I) obligations.
    Because Pennsylvania did not make a submission in its July 15, 2014
SIP submittals to address the requirements of section
110(a)(2)(D)(i)(I), EPA is not required to have proposed or to take
final SIP approval or disapproval action on this element under section
110(k) of the CAA. In this case, there has been no substantive
submission for EPA to evaluate under section 110(k). EPA interprets its
authority under section 110(k)(3) of the CAA as affording EPA the
discretion to approve, or conditionally approve, individual elements of
Pennsylvania's infrastructure SIP submissions, separate and apart from
any action with respect to the requirements of section
110(a)(2)(D)(i)(I) of the CAA. EPA views discrete infrastructure SIP
requirements in section 110(a)(2), such as the requirements of
110(a)(2)(D)(i)(I), as severable from the other infrastructure elements
and interprets section 110(k)(3) as allowing it to act on individual
severable measures in a plan submission.
    EPA acknowledges NJDEP's concern for the interstate transport of
air pollutants and agrees in general that sections 110(a)(1) and (a)(2)
of the CAA require states to submit, within three years of promulgation
of a new or revised NAAQS, a plan which addresses cross-state air
pollution under section 110(a)(2)(D)(i)(I). However, in this
rulemaking, EPA is only approving portions of Pennsylvania's
infrastructure SIP submissions for the 2008 ozone and 2010
SO2 NAAQS which did not include provisions for
110(a)(2)(D)(i)(I) for interstate transport. Findings of failure to
submit a SIP submission for a NAAQS addressing a specific element, such
as CAA section 110(a)(2)(D)(i)(I), would need to occur in separate
rulemakings. As that issue was not addressed in the February 6, 2015
NPR and is therefore not pertinent to this rulemaking, EPA provides no
further response. Pennsylvania's obligations regarding interstate
transport of ozone pollution for the 2008 ozone NAAQS will be addressed
in another rulemaking.

B. Sierra Club General Comments on Emission Limitations

1. The Plain Language of the CAA
    Comment 1: Sierra Club (hereafter referred to as Commenter)
contends that the plain language of section 110(a)(2)(A) of the CAA,
legislative history of the CAA, case law, EPA regulations such as 40
CFR 51.112(a), and EPA interpretations in rulemakings require the
inclusion of enforceable emission limits in an infrastructure SIP to
aid in attaining and maintaining the NAAQS and contends an
infrastructure SIP must be disapproved where emission limits are
inadequate to prevent exceedances of the NAAQS. The Commenter states
EPA may not approve an infrastructure SIP that fails to ensure
attainment and maintenance of the NAAQS.
    The Commenter states that the main objective of the infrastructure
SIP process ``is to ensure that all areas of the country meet the
NAAQS'' and states that nonattainment areas are addressed through
``nonattainment SIPs.'' The Commenter asserts the NAAQS ``are the
foundation upon which air emission standards for the entire country are
set'' including specific emission limitations for most large stationary
sources, such as coal-fired power plants. The Commenter discusses the
CAA's framework whereby states have primary responsibility to assure
air quality within the state pursuant to CAA section 107(a) which the
states carry out through SIPs such as infrastructure SIPs required by
section 110(a)(2). The Commenter also states that on its face the CAA
requires infrastructure SIPs ``to be adequate to prevent exceedances of
the NAAQS.'' In support, the Commenter quotes the language in section
110(a)(1) which requires states to adopt a plan for implementation,
maintenance, and enforcement of the NAAQS and the language in section
110(a)(2)(A) which requires SIPs to include enforceable emissions
limitations as may be necessary to meet the requirements of the CAA
which the Commenter claims includes attainment and maintenance of the
NAAQS. The Commenter notes the CAA definition of emission limit and
reads these CAA provisions together to require ``enforceable emission
limits on source emissions sufficient to ensure maintenance of the
NAAQS.''
    Response 1: EPA disagrees that section 110 is clear ``on its face''
and must be interpreted in the manner

suggested by the Commenter. As we have previously explained in response
to the Commenter's similar comments on EPA's action approving other
states' infrastructure SIPs, section 110 is only one provision that is
part of the complicated structure governing implementation of the NAAQS
program under the CAA, as amended in 1990, and it must be interpreted
in the context of not only that structure, but also of the historical
evolution of that structure.\4\
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    \4\ See 80 FR 11557 (March 4, 2015) (approval of Virginia
SO2 infrastructure SIP); 79 FR 62022 (October 16, 2014)
(approval of West Virginia SO2 infrastructure SIP); 79 FR
19001 (April 7, 2014) (approval of West Virginia ozone
infrastructure SIP); and 79 FR 17043 (March 27, 2014) (approval of
Virginia ozone infrastructure SIP).
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    EPA interprets infrastructure SIPs as more general planning SIPs,
consistent with the CAA as understood in light of its history and
structure. When Congress enacted the CAA in 1970, it did not include
provisions requiring states and the EPA to label areas as attainment or
nonattainment. Rather, states were required to include all areas of the
state in ``air quality control regions'' (AQCRs) and section 110 set
forth the core substantive planning provisions for these AQCRs. At that
time, Congress anticipated that states would be able to address air
pollution quickly pursuant to the very general planning provisions in
section 110 and could bring all areas into compliance with a new NAAQS
within five years. Moreover, at that time, section 110(a)(2)(A)(i)
specified that the section 110 plan provide for ``attainment'' of the
NAAQS and section 110(a)(2)(B) specified that the plan must include
``emission limitations, schedules, and timetables for compliance with
such limitations, and such other measures as may be necessary to insure
attainment and maintenance [of the NAAQS].''
    In 1977, Congress recognized that the existing structure was not
sufficient and many areas were still violating the NAAQS. At that time,
Congress for the first time added provisions requiring states and EPA
to identify whether areas of a state were violating the NAAQS (i.e.,
were nonattainment) or were meeting the NAAQS (i.e., were attainment)
and established specific planning requirements in section 172 for areas
not meeting the NAAQS. In 1990, many areas still had air quality not
meeting the NAAQS and Congress again amended the CAA and added yet
another layer of more prescriptive planning requirements for each of
the NAAQS. At that same time, Congress modified section 110 to remove
references to the section 110 SIP providing for attainment, including
removing pre-existing section 110(a)(2)(A) in its entirety and
renumbering subparagraph (B) as section 110(a)(2)(A). Additionally,
Congress replaced the clause ``as may be necessary to insure attainment
and maintenance [of the NAAQS]'' with ``as may be necessary or
appropriate to meet the applicable requirements of this chapter.''
Thus, the CAA has significantly evolved in the more than 40 years since
it was originally enacted. While at one time section 110 of the CAA did
provide the only detailed SIP planning provisions for states and
specified that such plans must provide for attainment of the NAAQS,
under the structure of the current CAA, section 110 is only the initial
stepping-stone in the planning process for a specific NAAQS. More
detailed, later-enacted provisions govern the substantive planning
process, including planning for attainment of the NAAQS.
    Thus, EPA believes that section 110 of the CAA is only one
provision that is part of the complicated structure governing
implementation of the NAAQS program under the CAA, as amended in 1990,
and it must be interpreted in the context of that structure and the
historical evolution of that structure. In light of the revisions to
section 110 since 1970 and the later-promulgated and more specific
planning requirements of the CAA, EPA reasonably interprets the
requirement in section 110(a)(2)(A) of the CAA that the plan provide
for ``implementation, maintenance and enforcement'' to mean that the
SIP must contain enforceable emission limits that will aid in attaining
and/or maintaining the NAAQS and that the state demonstrate that it has
the necessary tools to implement and enforce a NAAQS, such as adequate
state personnel and an enforcement program. EPA has interpreted the
requirement for emission limitations in section 110 to mean that the
state may rely on measures already in place to address the pollutant at
issue or any new control measures that the state may choose to submit.
Finally, as EPA stated in the Infrastructure SIP Guidance which
specifically provides guidance to states in addressing the 2008 ozone
and 2010 SO2 NAAQS, ``[t]he conceptual purpose of an
infrastructure SIP submission is to assure that the air agency's SIP
contains the necessary structural requirements for the new or revised
NAAQS, whether by establishing that the SIP already contains the
necessary provisions, by making a substantive SIP revision to update
the SIP, or both.'' Infrastructure SIP Guidance at p. 2.\5\
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    \5\ Thus, EPA disagrees with the Commenter's general assertion
that the main objective of infrastructure SIPs is to ensure all
areas of the country meet the NAAQS, as we believe the
infrastructure SIP process is the opportunity to review the
structural requirements of a state's air program. While the NAAQS
can be a foundation upon which emission limitations are set, as
explained in responses to subsequent comments, these emission
limitations are generally set in the attainment planning process
envisioned by part D of title I of the CAA, including, but not
limited to, CAA sections 172, 181-182, and 191-192.
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    The Commenter makes general allegations that Pennsylvania does not
have sufficient protective measures to prevent ozone violations/
exceedances and SO2 NAAQS exceedances. EPA addressed the
adequacy of Pennsylvania's infrastructure SIP for 110(a)(2)(A) purposes
to meet applicable requirements of the CAA in the TSD accompanying the
February 6, 2015 NPR and explained why the SIP includes enforceable
emission limitations and other control measures necessary for
maintenance of the 2008 ozone and 2010 SO2 NAAQS throughout
the Commonwealth.\6\
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    \6\ The TSD for this action is available on line at
www.regulations.gov, Docket ID Number EPA-R03-OAR-2014-0910.
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2. The Legislative History of the CAA
    Comment 2: The Commenter cites two excerpts from the legislative
history of the 1970 CAA claiming they support an interpretation that
SIP revisions under CAA section 110 must include emissions limitations
sufficient to show maintenance of the NAAQS in all areas of the state.
The Commenter also contends that the legislative history of the CAA
supports the interpretation that infrastructure SIPs under section
110(a)(2) must include enforceable emission limitations, citing the
Senate Committee Report and the subsequent Senate Conference Report
accompanying the 1970 CAA.
    Response 2: As provided in the previous response, the CAA, as
enacted in 1970, including its legislative history, cannot be
interpreted in isolation from the later amendments that refined that
structure and deleted relevant language from section 110 concerning
demonstrating attainment. See also 79 FR at 17046 (responding to
comments on Virginia's ozone infrastructure SIP). In any event, the two
excerpts of legislative history the Commenter cites merely provide that
states should include enforceable emission limits in their SIPs, and
they do not mention or otherwise address whether states are required to
include maintenance plans for all areas of the state as part of the
infrastructure SIP. As provided in

response to another comment in this rulemaking, the TSD for the
proposed rule explains why the Pennsylvania SIP includes enforceable
emissions limitations for ozone precursors and for SO2 for
the relevant areas.
3. Case Law
    Comment 3: The Commenter also discusses several cases applying the
CAA which the Commenter claims support its contention that courts have
been clear that section 110(a)(2)(A) requires enforceable emissions
limits in infrastructure SIPs to prevent exceedances of the NAAQS. The
Commenter first cites to language in Train v. NRDC, 421 U.S. 60, 78
(1975), addressing the requirement for ``emission limitations'' and
stating that emission limitations ``are specific rules to which
operators of pollution sources are subject, and which, if enforced,
should result in ambient air which meet the national standards.'' The
Commenter also cites to Pennsylvania Dept. of Envtl. Resources v. EPA,
932 F.2d 269, 272 (3d Cir. 1991) for the proposition that the CAA
directs EPA to withhold approval of a SIP where it does not ensure
maintenance of the NAAQS, and to Mision Industrial, Inc. v. EPA, 547
F.2d 123, 129 (1st Cir. 1976), which quoted section 110(a)(2)(B) of the
CAA of 1970. The Commenter contends that the 1990 Amendments do not
alter how courts have interpreted the requirements of section 110,
quoting Alaska Dept. of Envtl. Conservation v. EPA, 540 U.S. 461, 470
(2004) which in turn quoted section 110(a)(2)(A) of the CAA and also
stated that ``SIPs must include certain measures Congress specified''
to ensure attainment of the NAAQS. The Commenter also quotes several
additional opinions in this vein. Mont. Sulphur & Chem. Co. v. EPA, 666
F.3d 1174, 1180 (9th Cir. 2012) (``The Clean Air Act directs states to
develop implementation plans--SIPs--that `assure' attainment and
maintenance of [NAAQS] through enforceable emissions limitations'');
Hall v. EPA 273 F.3d 1146, 1153 (9th Cir. 2001) (``Each State must
submit a [SIP] that specif[ies] the manner in which [NAAQS] will be
achieved and maintained within each air quality control region in the
State''); Conn. Fund for Env't, Inc. v. EPA, 696 F.2d 169, 172 (D.C.
Cir. 1982) (CAA requires SIPs to contain ``measures necessary to ensure
attainment and maintenance of NAAQS''). Finally, the Commenter cites
Mich. Dept. of Envtl. Quality v. Browner, 230 F.3d 181 (6th Cir. 2000)
for the proposition that EPA may not approve a SIP revision that does
not demonstrate how the rules would not interfere with attainment and
maintenance of the NAAQS.
    Response 3: None of the cases the Commenter cites support its
contention that section 110(a)(2)(A) is clear that infrastructure SIPs
must include detailed plans providing for attainment and maintenance of
the NAAQS in all areas of the state, nor do they shed light on how
section 110(a)(2)(A) may reasonably be interpreted. With the exception
of Train, none of the cases the Commenter cites concerned the
interpretation of CAA section 110(a)(2)(A) (or section 110(a)(2)(B) of
the pre-1990 Act). Rather, the courts reference section 110(a)(2)(A)
(or section 110(a)(2)(B) of the pre-1990 CAA) in the background
sections of decisions in the context of a challenge to an EPA action on
revisions to a SIP that was required and approved or disapproved as
meeting other provisions of the CAA or in the context of an enforcement
action.
    In Train, 421 U.S. 60, the Court was addressing a state revision to
an attainment plan submission made pursuant to section 110 of the CAA,
the sole statutory provision at that time regulating such submissions.
The issue in that case concerned whether changes to requirements that
would occur before attainment was required were variances that should
be addressed pursuant to the provision governing SIP revisions or were
``postponements'' that must be addressed under section 110(f) of the
CAA of 1970, which contained prescriptive criteria. The Court concluded
that EPA reasonably interpreted section 110(f) not to restrict a
state's choice of the mix of control measures needed to attain the
NAAQS and that revisions to SIPs that would not impact attainment of
the NAAQS by the attainment date were not subject to the limits of
section 110(f). Thus the issue was not whether a section 110 SIP needs
to provide for attainment or whether emissions limits providing such
are needed as part of the SIP; rather the issue was which statutory
provision governed when the state wanted to revise the emission limits
in its SIP if such revision would not impact attainment or maintenance
of the NAAQS. To the extent the holding in the case has any bearing on
how section 110(a)(2)(A) might be interpreted, it is important to
realize that in 1975, when the opinion was issued, section 110(a)(2)(B)
(the predecessor to section 110(a)(2)(A)) expressly referenced the
requirement to attain the NAAQS, a reference that was removed in 1990.
    The decision in Pennsylvania Dept. of Envtl. Resources was also
decided based on the pre-1990 provision of the CAA. At issue was
whether EPA properly rejected a revision to an approved plan where the
inventories relied on by the state for the updated submission had gaps.
The Court quoted section 110(a)(2)(B) of the pre-1990 CAA in support of
EPA's disapproval, but did not provide any interpretation of that
provision. Yet, even if the Court had interpreted that provision, EPA
notes that it was modified by Congress in 1990; thus, this decision has
little bearing on the issue here.
    At issue in Mision Industrial, 547 F.2d 123, was the definition of
``emissions limitation,'' not whether section 110 requires the state to
demonstrate how all areas of the state will attain and maintain the
NAAQS as part of their infrastructure SIPs. The language from the
opinion the Commenter quotes does not interpret but rather merely
describes section 110(a)(2)(A). The Commenter does not raise any
concerns about whether the measures relied on by the Commonwealth in
the infrastructure SIPs are ``emissions limitations'' and the decision
in this case has no bearing here.\7\ In Mont. Sulphur & Chem. Co., 666
F.3d 1174, the Court was not reviewing an infrastructure SIP, but
rather EPA's disapproval of a SIP and promulgation of a federal
implementation plan (FIP) after a long history of the state failing to
submit an adequate SIP in response to EPA's finding under section
110(k)(5) that the previously approved SIP was substantially inadequate
to attain or maintain the NAAQS. The Court cited generally to sections
107 and 110(a)(2)(A) of the CAA for the proposition that SIPs should
assure attainment and maintenance of NAAQS through emission
limitations, but this language was not part of the Court's holding in
the case, which focused instead on whether EPA's finding of SIP
inadequacy, disapproval of the state's required responsive attainment
demonstration under section 110(k)(5), and adoption of a remedial FIP
under section 110(c) were lawful. The Commenter suggests that Alaska
Dept. of Envtl. Conservation, 540 U.S. 461, stands for the proposition
that the 1990 CAA Amendments do not alter how courts interpret section
110. This claim is inaccurate. Rather, the Court quoted section
110(a)(2)(A), which, as noted previously, differs from the pre-1990
version of that provision and the Court

made no mention of the changed language. Furthermore, the Commenter
also quotes the Court's statement that ``SIPs must include certain
measures Congress specified,'' but that statement specifically
referenced the requirement in section 110(a)(2)(C), which requires an
enforcement program and a program for the regulation of the
modification and construction of new sources. Notably, at issue in that
case was the state's ``new source'' permitting program, not its
infrastructure SIP.
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    \7\ While the Commenter does contend that the Commonwealth
shouldn't be allowed to rely on emission reductions that were
developed for the prior standards (which we address herein), it does
not claim that any of the measures are not ``emissions limitations''
within the definition of the CAA.
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    Two of the other cases the Commenter cites, Mich. Dept. of Envtl.
Quality, 230 F.3d 181, and Hall, 273 F.3d 1146, interpret CAA section
110(l), the provision governing ``revisions'' to plans, and not the
initial plan submission requirement under section 110(a)(2) for a new
or revised NAAQS, such as the infrastructure SIP at issue in this
instance. In those cases, the courts cited to section 110(a)(2)(A)
solely for the purpose of providing a brief background of the CAA.
    EPA does not believe any of these court decisions addressed
required measures for infrastructure SIPs and believes nothing in the
opinions addressed whether infrastructure SIPs need to contain measures
to ensure attainment and maintenance of the NAAQS.
4. EPA Regulations, Such as 40 CFR 51.112(a)
    Comment 4: The Commenter cites to 40 CFR 51.112(a), providing that
``[e]ach plan must demonstrate that the measures, rules and regulations
contained in it are adequate to provide for the timely attainment and
maintenance of the [NAAQS].'' The Commenter asserts that this
regulation requires infrastructure SIPs to include emissions limits
necessary to ensure attainment and maintenance of the NAAQS. The
Commenter states that the provisions of 40 CFR 51.112 are not limited
to nonattainment SIPs and instead applies to infrastructure SIPs which
are required to attain and maintain the NAAQS in areas not designated
nonattainment. The Commenter relies on a statement in the preamble to
the 1986 action restructuring and consolidating provisions in part 51,
in which EPA stated that ``[i]t is beyond the scope of th[is]
rulemaking to address the provisions of Part D of the Act . . .'' 51 FR
40656, 40656 (November 7, 1986). The Commenter asserts 40 CFR 51.112(a)
identifies the plans to which it applies as those that implement the
NAAQS.
    Response 4: The Commenter's reliance on 40 CFR 51.112 to support
its argument that infrastructure SIPs must contain emission limits
adequate to ensure attainment and maintenance of the NAAQS is not
supported. As an initial matter, EPA notes this regulatory provision
was initially promulgated and later restructured and consolidated prior
to the CAA Amendments of 1990, in which Congress removed all references
to ``attainment'' in section 110(a)(2)(A). And, it is clear on its face
that 40 CFR 51.112 applies to plans specifically designed to attain the
NAAQS. EPA interprets these provisions to apply when states are
developing ``control strategy'' SIPs such as the detailed attainment
and maintenance plans required under other provisions of the CAA, as
amended in 1977 and again in 1990, such as sections 175A, 181-182, and
191-192. The Commenter suggests that these provisions must apply to
section 110 SIPs because in the preamble to EPA's action
``restructuring and consolidating'' provisions in part 51, EPA stated
that the new attainment demonstration provisions in the 1977 Amendments
to the CAA were ``beyond the scope'' of the rulemaking. It is important
to note, however, that EPA's action in 1986 was not to establish new
substantive planning requirements, but rather was meant merely to
consolidate and restructure provisions that had previously been
promulgated. EPA noted that it had already issued guidance addressing
the new ``Part D'' attainment planning obligations. Also, as to
maintenance regulations, EPA expressly stated that it was not making
any revisions other than to re-number those provisions. 51 FR 40657.
    Although EPA was explicit that it was not establishing requirements
interpreting the provisions of new ``Part D'' of the CAA, it is clear
that the regulations being restructured and consolidated were intended
to address control strategy plans. In the preamble, EPA clearly stated
that 40 CFR 51.112 was replacing 40 CFR 51.13 (``Control strategy:
SOx and PM (portion)''), 51.14 (``Control strategy: CO, HC,
Ox and NO2 (portion)''), 51.80 (``Demonstration
of attainment: Pb (portion)''), and 51.82 (``Air quality data
(portion)''). Id. at 40660. Thus, the present-day 40 CFR 51.112
contains consolidated provisions that are focused on control strategy
SIPs, and the infrastructure SIP is not such a plan.
5. EPA Interpretations in Other Rulemakings
    Comment 5: The Commenter also references a prior EPA rulemaking
action where EPA disapproved a SIP and claims that action shows EPA
relied on section 110(a)(2)(A) and 40 CFR 51.112 to reject the SIP. The
Commenter points to a 2006 partial approval and partial disapproval of
revisions to Missouri's existing control strategy plans addressing the
SO2 NAAQS. The Commenter claims EPA cited section
110(a)(2)(A) for disapproving a revision to the state plan on the basis
that the State failed to demonstrate the SIP was sufficient to ensure
maintenance of the SO2 NAAQS after revision of an emission
limit and claims EPA cited to 40 CFR 51.112 as requiring that a plan
demonstrates the rules in a SIP are adequate to attain the NAAQS. The
Commenter claims the revisions to Missouri's control strategy SIP for
SO2 were rejected by EPA because the revised control
strategy limits were also in Missouri's infrastructure SIP and thus the
weakened limits would have impacted the infrastructure SIP's ability to
aid in attaining and maintaining the NAAQS.
    Response 5: EPA does not agree that the prior Missouri rulemaking
action referenced by the Commenter establishes how EPA reviews
infrastructure SIPs. It is clear from the final Missouri rule that EPA
was not reviewing initial infrastructure SIP submissions under section
110 of the CAA, but rather reviewing revisions that would make an
already approved SIP designed to demonstrate attainment of the NAAQS
less stringent. EPA's partial approval and partial disapproval of
revisions to restrictions on emissions of sulfur compounds for the
Missouri SIP in 71 FR 12623 addressed a control strategy SIP and not an
infrastructure SIP. Nothing in that action addresses the necessary
content of the initial infrastructure SIP for a new or revised NAAQS.

C. Sierra Club Comments on Pennsylvania SIP SO2 Emission
Limits

    The Commenter contends that the Pennsylvania 2008 ozone and 2010
SO2 infrastructure SIP revisions did not revise the existing
ozone precursor emission limits and SO2 emission limits in
response to the 2008 ozone and 2010 SO2 NAAQS and fail to
comport with assorted CAA requirements for SIPs to establish
enforceable emission limits that are adequate to prohibit NAAQS
exceedances in areas not designated nonattainment. EPA will address
SO2 comments and ozone comments respectively.
    Comment 6: Citing section 110(a)(2)(A) of the CAA, the Commenter
contends that EPA may not approve Pennsylvania's proposed 2010
SO2 infrastructure SIP because it does not include
enforceable 1-hour SO2 emission limits for sources currently

allowed to cause ``NAAQS exceedances.'' The Commenter asserts the
proposed infrastructure SIP fails to include enforceable 1-hour
SO2 emissions limits or other required measures to ensure
attainment and maintenance of the SO2 NAAQS in areas not
designated nonattainment as the Commenter claims is required by section
110(a)(2)(A). The Commenter asserts an infrastructure SIP must ensure,
through state-wide regulations or source specific requirements, proper
mass limitations and emissions rates with short term averaging on
specific large sources of pollutants such as power plants. The
Commenter asserts that emission limits are especially important for
meeting the 1-hour SO2 NAAQS because SO2 impacts
are strongly source-oriented. The Commenter states coal-fired electric
generating units (EGUs) are large contributors to SO2
emissions but contends Pennsylvania did not demonstrate that emissions
allowed by the proposed infrastructure SIP from such large sources of
SO2 will ensure compliance with the 2010 1-hour
SO2 NAAQS. The Commenter claims the proposed infrastructure
SIP would allow major sources to continue operating with present
emission limits.\8\ The Commenter then refers to air dispersion
modeling it conducted for five coal-fired EGUs in Pennsylvania,
including Brunner Island Steam Electric Station, Montour Steam Electric
Station, Cheswick Power Station, New Castle Power Plant, and Shawville
Coal Plant. The Commenter asserts the results of the air dispersion
modeling it conducted employing EPA's AERMOD program for modeling used
the plants' allowable emissions and showed the plants could cause
exceedances of the 2010 SO2 NAAQS with allowable
emissions.\9\ Based on the modeling, the Commenter asserts the
Pennsylvania SO2 infrastructure SIP submittal authorizes the
EGUs to cause exceedances of the NAAQS with allowable emission rates
and therefore the infrastructure SIP fails to include adequate
enforceable emission limitations or other required measures for sources
of SO2 sufficient to ensure attainment and maintenance of
the 2010 SO2 NAAQS.\10\ The Commenter therefore asserts EPA
must disapprove Pennsylvania's proposed 2010 SO2
infrastructure SIP revision. In addition, the Commenter asserts ``EPA
may only approve an I-SIP that incorporates enforceable emission
limitations on major sources of SO2 pollution in the state,
including coal-fired power plants, with one-hour averaging times that
are no less stringent than the modeling based limits . . . necessary to
protect the one-hour SO2 NAAQS and attain and maintain the
standard in Pennsylvania. These emission limits must apply at all times
. . . to ensure that Pennsylvania is able to attain and maintain the
2010 SO2 NAAQS.'' The Commenter claimed additional modeling
for two EGUs, Brunner Island and Montour, done with actual historical
hourly SO2 emissions show these facilities have actually
been causing ``exceedances of the NAAQS'' while operating pursuant to
existing emission limits which the Commenter claims Pennsylvania
included as part of the SO2 infrastructure SIP submission.
The Commenter also asserts that any coal-fired units slated for
retirement should be incorporated into the infrastructure SIP with an
enforceable emission limit or control measure.
---------------------------------------------------------------------------

    \8\ The Commenter provides a chart in its comments claiming 80
percent of SO2 emissions in Pennsylvania are from coal-
electric generating units based on 2011 data.
    \9\ The Commenter asserts its modeling followed protocols
pursuant to 40 CFR part 51, Appendix W and EPA's modeling guidance
issued March 2011 and December 2013.
    \10\ The Commenter again references 40 CFR 51.112 in support of
its position that the infrastructure SIP must include emission
limits for attainment and maintenance of the 2010 SO2
NAAQS.
---------------------------------------------------------------------------

    Response 6: EPA disagrees with the Commenter that EPA must
disapprove Pennsylvania's SO2 infrastructure SIP for the
reasons provided by the Commenter including the Commenter's modeling
results and insufficient SO2 emission limits. EPA is not in
this action making a determination regarding the Commonwealth's current
air quality status or regarding whether its control strategy is
sufficient to attain and maintain the NAAQS. Therefore, EPA is not
making any judgment on whether the Commenter's submitted modeling
demonstrates the NAAQS exceedances that the Commenter claims. EPA
believes that section 110(a)(2)(A) of the CAA is reasonably interpreted
to require states to submit infrastructure SIPs that reflect the first
step in their planning for attainment and maintenance of a new or
revised NAAQS. These SIP revisions should contain a demonstration that
the state has the available tools and authority to develop and
implement plans to attain and maintain the NAAQS and show that the SIP
has enforceable control measures. In light of the structure of the CAA,
EPA's long-standing position regarding infrastructure SIPs is that they
are general planning SIPs to ensure that the state has adequate
resources and authority to implement a NAAQS in general throughout the
state and not detailed attainment and maintenance plans for each
individual area of the state. As mentioned above, EPA has interpreted
this to mean, with regard to the requirement for emission limitations
that states may rely on measures already in place to address the
pollutant at issue or any new control measures that the state may
choose to submit.
    As stated in response to a previous more general comment, section
110 of the CAA is only one provision that is part of the complicated
structure governing implementation of the NAAQS program under the CAA,
as amended in 1990, and it must be interpreted in the context of not
only that structure, but also of the historical evolution of that
structure. In light of the revisions to section 110 since 1970 and the
later-promulgated and more specific planning requirements of the CAA,
EPA reasonably interprets the requirement in section 110(a)(2)(A) of
the CAA that the plan provide for ``implementation, maintenance and
enforcement'' to mean that the SIP must contain enforceable emission
limits that will aid in attaining and/or maintaining the NAAQS and that
the Commonwealth demonstrate that it has the necessary tools to
implement and enforce a NAAQS, such as adequate state personnel and an
enforcement program. As discussed above, EPA has interpreted the
requirement for emission limitations in section 110 to mean that the
state may rely on measures already in place to address the pollutant at
issue or any new control measures that the state may choose to submit.
Finally, as EPA stated in the Infrastructure SIP Guidance which
specifically provides guidance to states in addressing the 2010
SO2 NAAQS and the 2008 Ozone NAAQS, ``[t]he conceptual
purpose of an infrastructure SIP submission is to assure that the air
agency's SIP contains the necessary structural requirements for the new
or revised NAAQS, whether by establishing that the SIP already contains
the necessary provisions, by making a substantive SIP revision to
update the SIP, or both.'' Infrastructure SIP Guidance at p. 2.
    On April 12, 2012, EPA explained its expectations regarding
implementation of the 2010 SO2 NAAQS via letters to each of
the states. EPA communicated in the April 2012 letters that all states
were expected to submit SIPs meeting the ``infrastructure'' SIP
requirements under section 110(a)(2) of the CAA by June 2013. At the
time, EPA was undertaking a stakeholder outreach process to continue to
develop possible approaches for determining attainment status under the
SO2 NAAQS and

implementing this NAAQS. EPA was abundantly clear in the April 2012
letters that EPA did not expect states to submit substantive attainment
demonstrations or modeling demonstrations showing attainment for areas
not designated nonattainment in infrastructure SIPs due in June 2013.
Although EPA had previously suggested in its 2010 SO2 NAAQS
preamble and in prior draft implementation guidance in 2011 that states
should, in the unique SO2 context, use the section 110(a)
SIP process as the vehicle for demonstrating attainment of the NAAQS,
this approach was never adopted as a binding requirement and was
subsequently discarded in the April 2012 letters to states. The April
2012 letters recommended states focus infrastructure SIPs due in June
2013, such as Pennsylvania's SO2 infrastructure SIP, on
traditional ``infrastructure elements'' in section 110(a)(1) and (2)
rather than on modeling demonstrations for future attainment for areas
not designated as nonattainment.\11\
---------------------------------------------------------------------------

    \11\ In EPA's final SO2 NAAQS preamble (75 FR 35520
(June 22, 2010)) and subsequent draft guidance in March and
September 2011, EPA had expressed its expectation that many areas
would be initially designated as unclassifiable due to limitations
in the scope of the ambient monitoring network and the short time
available before which states could conduct modeling to support
their designations recommendations due in June 2011. In order to
address concerns about potential violations in these unclassifiable
areas, EPA initially recommended that states submit substantive
attainment demonstration SIPs based on air quality modeling by June
2013 (under section 110(a)) that show how their unclassifiable areas
would attain and maintain the NAAQS in the future. Implementation of
the 2010 Primary 1-Hour SO2 NAAQS, Draft White Paper for
Discussion, May 2012 (2012 Draft White Paper) (for discussion
purposes with Stakeholders at meetings in May and June 2012),
available at http://www.epa.gov/airquality/sulfurdioxide/implement.html. However, EPA clearly stated in this 2012 Draft White
Paper its clarified implementation position that it was no longer
recommending such attainment demonstrations for unclassifiable areas
for June 2013 infrastructure SIPs. Id. EPA had stated in the
preamble to the NAAQS and in the prior 2011 draft guidance that EPA
intended to develop and seek public comment on guidance for modeling
and development of SIPs for sections 110 and 191 of the CAA. Section
191 of the CAA requires states to submit SIPs in accordance with
section 172 for areas designated nonattainment with the
SO2 NAAQS. After seeking such comment, EPA has now issued
guidance for the nonattainment area SIPs due pursuant to sections
191 and 172. See Guidance for 1-Hour SO2 Nonattainment
Area SIP Submissions, Stephen D. Page, Director, EPA's Office of Air
Quality Planning and Standards, to Regional Air Division Directors
Regions 1-10, April 23, 2014. In September 2013, EPA had previously
issued specific guidance relevant to infrastructure SIP submissions
due for the NAAQS, including the 2010 SO2 NAAQS. See
Infrastructure SIP Guidance.
---------------------------------------------------------------------------

    Therefore, EPA asserts that evaluations of modeling demonstrations
such as those submitted by the Commenter are more appropriately to be
considered in actions that make determinations regarding states'
current air quality status or regarding future air quality status. EPA
also asserts that SIP revisions for SO2 nonattainment areas
including measures and modeling demonstrating attainment are due by the
dates statutorily prescribed under subpart 5 under part D. Those
submissions are due no later than 18 months after an area is designed
nonattainment for SO2, under CAA section 191(a). Thus, the
CAA directs states to submit these SIP requirements that are specific
for nonattainment areas on a separate schedule from the ``structural
requirements'' of 110(a)(2) which are due within three years of
adoption or revision of a NAAQS and which apply statewide. The
infrastructure SIP submission requirement does not move up the date for
any required submission of a part D plan for areas designated
nonattainment for the new NAAQS. Thus, elements relating to
demonstrating attainment for areas not attaining the NAAQS are not
necessary for infrastructure SIP submissions, and the CAA does not
provide explicit requirements for demonstrating attainment for areas
that have not yet been designated regarding attainment with a
particular NAAQS.
    As stated previously, EPA believes that the proper inquiry at this
juncture is whether Pennsylvania has met the basic structural SIP
requirements appropriate at the point in time EPA is acting upon the
infrastructure submittal. Emissions limitations and other control
measures needed to attain the NAAQS in areas designated nonattainment
for that NAAQS are due on a different schedule from the section 110
infrastructure elements. A state, like Pennsylvania, may reference pre-
existing SIP emission limits or other rules contained in part D plans
for previous NAAQS in an infrastructure SIP submission. Pennsylvania's
existing rules and emission reduction measures in the SIP that control
emissions of SO2 were discussed in the TSD. These provisions
have the ability to reduce SO2 overall. Although the
Pennsylvania SIP relies on measures and programs used to implement
previous SO2 NAAQS, these provisions are not limited to
reducing SO2 levels to meet one specific NAAQS and will
continue to provide benefits for the 2010 SO2 NAAQS.
    Additionally, as discussed in EPA's TSD supporting the NPR,
Pennsylvania has the ability to revise its SIP when necessary (e.g. in
the event the Administrator finds the plan to be substantially
inadequate to attain the NAAQS or otherwise meet all applicable CAA
requirements) as required under element H of section 110(a)(2). See
Section 4(1) of the APCA, 35 P.S. Sec.  4004(1), which empowers PADEP
to implement the provisions of the CAA. Section 5 of the APCA, 35 P.S.
Sec.  4005, authorizes the Environmental Quality Board (EQB) to adopt
rules and regulations for the prevention, control, reduction and
abatement of air pollution throughout the Commonwealth.
    EPA believes the requirements for emission reduction measures for
an area designated nonattainment for the 2010 primary SO2
NAAQS are in sections 172 and 191-192 of the CAA, and therefore, the
appropriate avenue for implementing requirements for necessary emission
limitations for demonstrating attainment with the 2010 SO2
NAAQS is through the attainment planning process contemplated by those
sections of the CAA. On August 5, 2013, EPA designated as nonattainment
most areas in locations where existing monitoring data from 2009-2011
indicated violations of the 1-hour SO2 standard. 78 FR
47191. At that time, four areas in Pennsylvania had monitoring data
from 2009-2011 indicating violations of the 1-hour SO2
standard, and these areas were designated nonattainment in
Pennsylvania. See 40 CFR 81.339. Also on March 2, 2015 the United
States District Court for the Northern District of California entered a
Consent Decree among the EPA, Sierra Club and Natural Resources Defense
Council to resolve litigation concerning the deadline for completing
designations for the 2010 SO2 NAAQS. Pursuant to the terms
of the Consent Decree, EPA will complete additional designations for
all remaining areas of the country including remaining areas in
Pennsylvania.\12\
---------------------------------------------------------------------------

    \12\ The Consent Decree, entered March 2, 2015 by the United
States District Court for the Northern District of California in
Sierra Club and NRDC v. EPA, Case 3:13-cv-03953-SI (N.D. Cal.) is
available at http://www.epa.gov/airquality/sulfurdioxide/designations/pdfs/201503FinalCourtOrder.pdf.
---------------------------------------------------------------------------

    For the four areas designated nonattainment in Pennsylvania in
August 2013, attainment SIPs were due by April 4, 2015 and must contain
demonstrations that the areas will attain the 2010 SO2 NAAQS
as expeditiously as practicable, but no later than October 4, 2018
pursuant to sections 172, 191 and 192, including a plan for enforceable
measures to reach attainment of the NAAQS. Similar attainment planning
SIPs for any additional areas which EPA subsequently designates
nonattainment with the 2010 SO2 NAAQS will be due for such
areas within the timeframes specified in CAA section 191. EPA

believes it is not appropriate to interpret the overall section
110(a)(2) infrastructure SIP obligation to require bypassing the
attainment planning process by imposing separate requirements outside
the attainment planning process. Such actions would be disruptive and
premature absent exceptional circumstances and would interfere with a
state's planning process. See In the Matter of EME Homer City
Generation LP and First Energy Generation Corp., Order on Petitions
Numbers III-2012-06, III-2012-07, and III 2013-01 (July 30, 2014)
(hereafter, Homer City/Mansfield Order) at 10-19 (finding Pennsylvania
SIP did not require imposition of 1-hour SO2 emission limits
on sources independent of the part D attainment planning process
contemplated by the CAA). EPA believes that the history of the CAA and
intent of Congress for the CAA as described above demonstrate clearly
that it is within the section 172 and general part D attainment
planning process that Pennsylvania must include 1-hour SO2
emission limits on sources, where needed, for the four areas designated
nonattainment to reach attainment with the 2010 1-hour SO2
NAAQS and for any additional areas EPA may subsequently designate
nonattainment.
    The Commenter's reliance on 40 CFR 51.112 to support its argument
that infrastructure SIPs must contain emission limits adequate to
provide for timely attainment and maintenance of the standard is also
not supported. As explained previously in response to the background
comments, EPA notes this regulatory provision applies to planning SIPs,
such as those demonstrating how an area will attain a specific NAAQS
and not to infrastructure SIPs which are intended to support that the
states have in place structural requirements necessary to implement the
NAAQS.
    As noted in EPA's preamble for the 2010 SO2 NAAQS,
determining compliance with the SO2 NAAQS will likely be a
source-driven analysis and EPA has explored options to ensure that the
SO2 designations process realistically accounts for
anticipated SO2 reductions at sources that we expect will be
achieved by current and pending national and regional rules. See 75 FR
35520. As mentioned previously, EPA will act in accordance with the
entered Consent Decree's schedule for conducting additional
designations for the 2010 SO2 NAAQS and any areas designated
nonattainment must meet the applicable part D requirements for these
areas. However, because the purpose of an infrastructure SIP submission
is for more general planning purposes, EPA does not believe
Pennsylvania was obligated during this infrastructure SIP planning
process to account for controlled SO2 levels at individual
sources. See Homer City/Mansfield Order at 10-19.
    Regarding the air dispersion modeling conducted by the Commenter
pursuant to AERMOD for the coal-fired plants including the Brunner
Island, Montour, Cheswick, New Castle and Shawville facilities, EPA
does not find the modeling information relevant at this time for review
of an infrastructure SIP. While EPA has extensively discussed the use
of modeling for attainment demonstration purposes and for designations,
EPA has affirmatively stated such modeling was not needed to
demonstrate attainment for the SO2 infrastructure SIPs under
the 2010 SO2 NAAQS. See April 12, 2012 letters to states
regarding SO2 implementation and Implementation of the 2010
Primary 1-Hour SO2 NAAQS, Draft White Paper for Discussion,
May 2012, available at http://www.epa.gov/airquality/sulfurdioxide/implement.html.\13\
---------------------------------------------------------------------------

    \13\ EPA has provided draft guidance for states regarding
modeling analyses to support the designations process for the 2010
SO2 NAAQS. SO2 NAAQS Designations Modeling
Technical Assistance Document (draft), EPA Office of Air and
Radiation and Office of Air Quality Planning and Standards, December
2013, available at http://www.epa.gov/airquality/sulfurdioxide/implement.html.
---------------------------------------------------------------------------

    EPA has proposed a Data Requirements Rule which, if promulgated,
will be relevant to the SO2 designations process. See, e.g.,
79 FR 27446 (May 13, 2014) (proposing process by which state air
agencies would characterize air quality around SO2 sources
through ambient monitoring and/or air quality modeling techniques and
submit such data to the EPA). The proposed rule includes a lengthy
discussion of how EPA anticipates addressing modeling that informs
determinations of states' air quality status under the 2010
SO2 NAAQS. As stated above, EPA believes it is not
appropriate to bypass the attainment planning process by imposing
separate attainment planning process requirements outside part D and
into the infrastructure SIP process.
    Finally, EPA also disagrees with the Commenter that the
Pennsylvania infrastructure SIP must, to be approved, incorporate the
planned retirement dates of coal-fired EGUs to ensure attainment and
maintenance of the SO2 NAAQS. Because EPA does not believe
Pennsylvania's infrastructure SIP requires at this time 1-hour
SO2 emission limits on these sources or other large
stationary sources to ensure attainment or maintenance or ``prevent
exceedances'' of the 2010 SO2 NAAQS, EPA likewise does not
believe incorporating planned retirement dates for SO2
emitters is necessary for our approval of an infrastructure SIP which
we have explained meets the structural requirements of section
110(a)(2). Pennsylvania can address any SO2 emission
reductions that may be needed to attain the 2010 SO2 NAAQS,
including reductions through source retirements, in the separate
attainment planning process of part D of title I of the CAA for areas
designated nonattainment.
    In conclusion, EPA disagrees with the Commenter's statements that
EPA must disapprove Pennsylvania's infrastructure SIP submission
because it does not establish specific enforceable SO2
emission limits, either on coal-fired EGUs or other large
SO2 sources, in order to demonstrate attainment and
maintenance with the NAAQS at this time.\14\
---------------------------------------------------------------------------

    \14\ Finally, EPA does not disagree with the Commenter's claim
that coal fired EGUs are a large source of SO2 emissions
in Pennsylvania based on the 2011 NEI. However, EPA does not agree
that this information is relevant to our approval of the
infrastructure SIP which EPA has explained meets requirements in CAA
section 110(a)(2).
---------------------------------------------------------------------------

    Comment 7: The Commenter asserts that modeling is the appropriate
tool for evaluating adequacy of infrastructure SIPs and ensuring
attainment and maintenance of the 2010 SO2 NAAQS. The
Commenter refers to EPA's historic use of air dispersion modeling for
attainment designations as well as ``SIP revisions.'' The Commenter
cites to prior EPA statements that the Agency has used modeling for
designations and attainment demonstrations, including statements in the
2010 SO2 NAAQS preamble, EPA's 2012 Draft White Paper for
Discussion on Implementing the 2010 SO2 NAAQS, and a 1994
SO2 Guideline Document, as modeling could better address the
source-specific impacts of SO2 emissions and historic
challenges from monitoring SO2 emissions.\15\
---------------------------------------------------------------------------

    \15\ The Commenter also cites to a 1983 EPA Memorandum on
section 107 designations policy regarding use of modeling for
designations and to the 2012 Mont. Sulphur & Chem. Co. case which
upheld EPA's finding that the previously approved SIP for an area in
Montana was substantially inadequate to attain the NAAQS due to
modeled violations of the NAAQS.
---------------------------------------------------------------------------

    The Commenter also cited to several cases upholding EPA's use of
modeling in NAAQS implementation actions, including the Montana Sulphur
case, Sierra Club v. Costle, 657 F.2d 298 (D.C. Cir. 1981), Republic
Steel Corp. v. Costle, 621 F.2d 797 (6th Cir. 1980), and Catawba County
v. EPA, 571 F.3d 20

(D.C. Cir. 2009).\16\ The Commenter discusses statements made by EPA
staff regarding the use of modeling and monitoring in setting emission
limitations or determining ambient concentrations as a result of a
source's emissions, discussing performance of AERMOD as a model, if
AERMOD is capable of predicting whether the NAAQS is attained, and
whether individual sources contribute to SO2 NAAQS
violations. The Commenter cites to EPA's history of employing air
dispersion modeling for increment compliance verifications in the
permitting process for the Prevention of Significant Deterioration
(PSD) program required in part C of Title I of the CAA. The Commenter
claims several coal-fired EGUs including Brunner Island, Montour,
Cheswick, New Castle, and Shawville are examples of sources located in
elevated terrain where the AERMOD model functions appropriately in
evaluating ambient impacts.
---------------------------------------------------------------------------

    \16\ Montana Sulphur & Chemical Co. v. EPA, 666 F.3d 1174 (9th
Cir. 2012).
---------------------------------------------------------------------------

    The Commenter asserts EPA's use of air dispersion modeling was
upheld in GenOn REMA, LLC v. EPA, 722 F.3d 513 (3rd Cir. 2013) where an
EGU challenged EPA's use of CAA section 126 to impose SO2
emission limits on a source due to cross-state impacts. The Commenter
claims the Third Circuit in GenOn REMA upheld EPA's actions after
examining the record which included EPA's air dispersion modeling of
the one source as well as other data.
    The Commenter cites to Vehicle Mfrs. Ass'n v. State Farm Mut. Auto
Ins. Co., 463 U.S. 29,43 (1983) and NRDC v. EPA, 571 F.3d 1245, 1254
(D.C. Cir. 2009) for the general proposition that it would be arbitrary
and capricious for an agency to ignore an aspect of an issue placed
before it and that an agency must consider information presented during
notice-and-comment rulemaking.\17\
---------------------------------------------------------------------------

    \17\ The Commenter also claims it raised similar arguments to
Pennsylvania during the Pennsylvania proposal process for the
infrastructure SIPs.
---------------------------------------------------------------------------

    Finally, the Commenter claims that Pennsylvania's proposed
SO2 infrastructure SIP lacks emission limitations informed
by air dispersion modeling and therefore fails to ensure Pennsylvania
will attain and maintain the 2010 SO2 NAAQS. The Commenter
claims EPA must disapprove the SO2 infrastructure SIP as it
does not ``prevent exceedances'' or ensure attainment and maintenance
of the SO2 NAAQS.
    Response 7: EPA agrees with the Commenter that air dispersion
modeling, such as AERMOD, can be an important tool in the CAA section
107 designations process for SO2 and in developing SIPs for
nonattainment areas as required by sections 172 and 191-192, including
supporting required attainment demonstrations. EPA agrees that prior
EPA statements, EPA guidance, and case law support the use of air
dispersion modeling in the SO2 designations process and
attainment demonstration process, as well as in analyses of the
interstate impact of transported emissions and whether existing
approved SIPs remain adequate to show attainment and maintenance of the
SO2 NAAQS. However, as provided in the previous responses,
EPA disagrees with the Commenter that EPA must disapprove the
Pennsylvania SO2 infrastructure SIP for its alleged failure
to include source-specific SO2 emission limits that show no
exceedances of the NAAQS when modeled or ensure attainment and
maintenance of the NAAQS.
    In acting to approve or disapprove an infrastructure SIP, EPA is
not required to make findings regarding current air quality status of
areas within the state, regarding such area's projected future air
quality status, or regarding whether existing emissions limits in such
area are sufficient to meet a NAAQS in the area. All of the actions the
Commenter cites, instead, do make findings regarding at least one of
those issues. The attainment planning process detailed in part D of the
CAA, including sections 172 and 191-192 attainment SIPs, is the
appropriate place for the state to evaluate measures needed to bring
in-state nonattainment areas into attainment with a NAAQS and to impose
additional emission limitations such as SO2 emission limits
on specific sources.
    EPA had initially recommended that states submit substantive
attainment demonstration SIPs based on air quality modeling in the
final 2010 SO2 NAAQS preamble (75 FR 35520) and in
subsequent draft guidance issued in September 2011 for the section
110(a) SIPs due in June 2013 in order to show how areas then-expected
to be designated as unclassifiable would attain and maintain the NAAQS.
These initial statements in the preamble and 2011 draft guidance,
presented only in the context of the new 1-hour SO2 NAAQS
and not suggested as a matter of general infrastructure SIP policy,
were based on EPA's expectation at the time, that by June 2012, most
areas would initially be designated as unclassifiable due to
limitations in the scope of the ambient monitoring network and the
short time available before which states could conduct modeling to
support designations recommendations in 2011. However, after conducting
extensive stakeholder outreach and receiving comments from the states
regarding these initial statements and the timeline for implementing
the NAAQS, EPA subsequently stated in the April 12, 2012 letters and in
the 2012 Draft White Paper that EPA was clarifying its 2010
SO2 NAAQS implementation position and was no longer
recommending such attainment demonstrations supported by air dispersion
modeling for unclassifiable areas (which had not yet been designated)
for the June 2013 infrastructure SIPs. Instead, EPA explained that it
expected states to submit infrastructure SIPs that followed the general
policy EPA had applied under other NAAQS. EPA then reaffirmed this
position in the February 6, 2013 memorandum, ``Next Steps for Area
Designations and Implementation of the Sulfur Dioxide National Ambient
Air Quality Standard.'' \18\ As previously mentioned, EPA had stated in
the preamble to the NAAQS and in the prior 2011 draft guidance that EPA
intended to develop and seek public comment on guidance for modeling
and development of SIPs for sections 110, 172 and 191-192 of the CAA.
After receiving such further comment, EPA has now issued guidance for
the nonattainment area SIPs due pursuant to sections 172 and 191-192.
See April 23, 2014 Guidance for 1-Hour SO2 Nonattainment
Area SIP Submissions. In addition, modeling may be an appropriate
consideration for states and EPA in further designations for the
SO2 NAAQS in accordance with the Sierra Club and NRDC
Consent Decree and proposed data requirements rule mentioned
previously.\19\ While the EPA guidance for attainment SIPs and for
designations for CAA section 107 and proposed process for
characterizing SO2 emissions from larger sources discuss the
use of air dispersion modeling, EPA's 2013 Infrastructure SIP Guidance
did not suggest that states use

air dispersion modeling for purposes of the section 110(a)(2)
infrastructure SIP. Therefore, as discussed previously, EPA believes
the Pennsylvania SO2 infrastructure SIP submittal contains
the structural requirements to address elements in section 110(a)(2) as
discussed in detail in the TSD accompanying the proposed approval. EPA
believes infrastructure SIPs are general planning SIPs to ensure that a
state has adequate resources and authority to implement a NAAQS.
Infrastructure SIP submissions are not intended to act or fulfill the
obligations of a detailed attainment and/or maintenance plan for each
individual area of the state that is not attaining the NAAQS. While
infrastructure SIPs must address modeling authorities in general for
section 110(a)(2)(K), EPA believes 110(a)(2)(K) requires infrastructure
SIPs to provide the state's authority for air quality modeling and for
submission of modeling data to EPA, not specific air dispersion
modeling for large stationary sources of pollutants. In the TSD for
this rulemaking action, EPA provided a detailed explanation of
Pennsylvania's ability and authority to conduct air quality modeling
when required and its authority to submit modeling data to the EPA.
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    \18\ The February 6, 2013 ``Next Steps for Area Designations and
Implementation of the Sulfur Dioxide National Ambient Air Quality
Standard,'' one of the April 12, 2012 state letters, and the May
2012 Draft White Paper are available at http://www.epa.gov/airquality/sulfurdioxide/implement.html.
    \19\ The Consent Decree in Sierra Club and NRDC v. EPA, Case
3:13-cv-03953-SI (N.D. Cal.) is available at http://www.epa.gov/airquality/sulfurdioxide/designations/pdfs/201503FinalCourtOrder.pdf. See 79 FR 27446 (EPA's proposed data
requirements rule). See also Updated Guidance for Area Designations
for the 2010 Primary Sulfur Dioxide National Ambient Air Quality
Standard, Stephen D. Page, Director, EPA's Office of Air Quality
Planning Standards, March 20, 2015, available at http://www.epa.gov/airquality/sulfurdioxide/pdfs/20150320SO2designations.pdf.>
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    EPA finds the Commenter's discussion of case law, guidance, and EPA
staff statements regarding advantages of AERMOD as an air dispersion
model for purposes of demonstrating attainment of the NAAQS to be
irrelevant to the analysis of Pennsylvania's infrastructure SIP, which
as we have explained is separate from the SIP required to demonstrate
attainment of the NAAQS pursuant to sections 172 or 192. In addition,
the Commenter's comments relating to EPA's use of AERMOD or modeling in
general in designations pursuant to section 107, including its citation
to Catawba County, are likewise irrelevant as EPA's present approval of
Pennsylvania's infrastructure SIP is unrelated to the section 107
designations process. Nor is EPA's action on this infrastructure SIP
related to any new source review (NSR) or PSD permit program issue. As
outlined in the August 23, 2010 clarification memo, ``Applicability of
Appendix W Modeling Guidance for the 1-hour SO2 National
Ambient Air Quality Standard'' (U.S. EPA, 2010a), AERMOD is the
preferred model for single source modeling to address the 1-hour
SO2 NAAQS as part of the NSR/PSD permit programs. Therefore,
as attainment SIPs, designations, and NSR/PSD actions are outside the
scope of a required infrastructure SIP for the 2010 SO2
NAAQS for section 110(a), EPA provides no further response to the
Commenter's discussion of air dispersion modeling for these
applications. If the Commenter resubmits its air dispersion modeling
for the Pennsylvania EGUs, or updated modeling information in the
appropriate context, EPA will address the resubmitted modeling or
updated modeling at that time.
    The Commenter correctly noted that the Third Circuit upheld EPA's
section 126 finding imposing SO2 emissions limitations on an
EGU pursuant to CAA section 126. GenOn REMA, LLC v. EPA, 722 F.3d 513.
Pursuant to section 126, any state or political subdivision may
petition EPA for a finding that any major source or group of stationary
sources emits, or would emit, any air pollutant in violation of the
prohibition of section 110(a)(2)(D)(i) which relates to significant
contributions to nonattainment or interference with maintenance of a
NAAQS in another state. The Third Circuit upheld EPA's authority under
section 126 and found EPA's actions neither arbitrary nor capricious
after reviewing EPA's supporting docket which included air dispersion
modeling as well as ambient air monitoring data showing exceedances of
the NAAQS. The Commenter appears to have cited to this matter to
demonstrate EPA's use of modeling for certain aspects of the CAA. We do
not disagree that such modeling is appropriate for other actions, such
as those under section 126. But, for the reasons explained above, such
modeling is not required for determining whether Pennsylvania's
infrastructure SIP has the required structural requirements pursuant to
section 110(a)(2). As noted above, EPA is not acting on an interstate
transport SIP in this action because Pennsylvania has not made such a
submission. The decision in GenOn Rema does not otherwise speak to the
role of air dispersion modeling as to any other planning requirements
in the CAA.
    In its comments, the Commenter relies on Motor Vehicle Mfrs. Ass'n
and NRDC v. EPA to support its comments that EPA must consider the
Commenter's modeling data on several Pennsylvania EGUs including
Brunner Island, Montour, Cheswick, New Castle, and Shawville based on
administrative law principles regarding consideration of comments
provided during a rulemaking process. For the reasons previously
explained, the purpose for which the Commenter submitted the modeling--
namely, to assert that current air quality in the areas in which those
sources are located does not meet the NAAQS--is not relevant to EPA's
action on this infrastructure SIP, and consequently EPA is not required
to consider the modeling in evaluating the approvability of the
infrastructure SIP.\20\ EPA does not believe infrastructure SIPs must
contain emission limitations informed by air dispersion modeling in
order to meet the requirements of section 110(a)(2)(A). Thus, EPA has
evaluated the persuasiveness of the Commenter's submitted modeling in
finding that it is not relevant to the approvability of Pennsylvania's
proposed infrastructure SIP for the 2010 SO2 NAAQS, but EPA
has made no judgment regarding whether the Commenter's submitted
modeling is sufficient to show violations of the NAAQS.
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    \20\ EPA notes that PADEP provided similar responses to the
Commenter's claims regarding evaluation of modeling data for an
infrastructure SIP as specifically recounted by the Commenter in its
March 9, 2015 comments to EPA on this rulemaking action. EPA agrees
with PADEP's responses that emissions limitations for attainment of
the NAAQS are appropriate for consideration in the part D planning
process and not for the infrastructure SIP process. Thus, EPA
provides no further response on this issue as PADEP responded to the
Commenter in Pennsylvania's rulemaking and EPA's responses are
provided in this action.
---------------------------------------------------------------------------

    While EPA does not believe that infrastructure SIP submissions are
required to contain emission limits assuring in-state attainment of the
NAAQS, as suggested by the Commenter, EPA does recognize that in the
past, states have, in their discretion, used infrastructure SIP
submittals as a `vehicle' for incorporating regulatory revisions or
source-specific emission limits into the state's plan. See 78 FR 73442
(December 6, 2013) (approving regulations Maryland submitted for
incorporation into the SIP along with the 2008 ozone infrastructure SIP
to address ethics requirements for State Boards in sections 128 and
110(a)(2)(E)(ii)). While these SIP revisions are intended to help the
state meet the requirements of section 110(a)(2), these ``ride-along''
SIP revisions are not intended to signify that all infrastructure SIP
submittals must, in order to be approved by EPA, have similar
regulatory revisions or source-specific emission limits. Rather, the
regulatory provisions and source-specific emission limits the state
relies on when showing compliance with section 110(a)(2) have, in many
cases, likely already been incorporated into the state's SIP prior to
each new infrastructure SIP submission; in some cases this was done for
entirely separate CAA requirements, such as attainment

plans required under section 172, or for previous NAAQS.
    Comment 8: The Commenter asserts that EPA may not approve the
Pennsylvania proposed SO2 infrastructure SIP because it
fails to include enforceable emission limitations with a 1-hour
averaging time that applies at all times. The Commenter cites to CAA
section 302(k) which requires emission limits to apply on a continuous
basis. The Commenter claims EPA has stated that 1-hour averaging times
are necessary for the 2010 SO2 NAAQS citing to EPA's April
23, 2014 Guidance for 1-Hour SO2 Nonattainment Area SIP
Submissions, a February 3, 2011, EPA Region 7 letter to the Kansas
Department of Health and Environment regarding the need for 1-hour
SO2 emission limits in a PSD permit, an EPA Environmental
Hearing Board (EHB) decision rejecting use of a 3-hour averaging time
for a SO2 limit in a PSD permit, and EPA's disapproval of a
Missouri SIP which relied on annual averaging for SO2
emission rates.\21\
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    \21\ Sierra Club cited to In re: Mississippi Lime Co.,
PSDAPLPEAL 11-01, 2011 WL 3557194, at *26-27 (EPA Aug. 9, 2011) and
71 FR 12623, 12624 (March 13, 2006) (EPA disapproval of a control
strategy SO2 SIP).
---------------------------------------------------------------------------

    Thus, the Commenter contends EPA must disapprove Pennsylvania's
infrastructure SIP which the Commenter claims fails to require emission
limits with adequate averaging times.
    Response 8: EPA disagrees that EPA must disapprove the proposed
Pennsylvania infrastructure SIP because the SIP does not contain
enforceable SO2 emission limitations with 1-hour averaging
periods that apply at all times, as this issue is not appropriate for
resolution at this stage. The comment does not assert that the
SO2 emission limits in Pennsylvania's SIP are not
enforceable or that they do not apply at all times, instead the comment
focuses on the lack of 1-hour averaging times. We do not believe, as
suggested by the Commenter, that the emission limits are not
``continuous'' within the meaning of section 302(k). As EPA has noted
previously, the purpose of the section 110(a)(2) SIP is to ensure that
the State has the necessary structural components to implement programs
for attainment and maintenance of the NAAQS.\22\ While EPA does agree
that the averaging time is a critical consideration for purposes of
substantive SIP revisions, such as attainment demonstrations, the
averaging time of existing rules in the SIP is not relevant for
determining that the State has met the applicable requirements of
section 110(a)(2) with respect to the infrastructure elements addressed
in the present SIP action.\23\ Therefore, because EPA finds
Pennsylvania's SO2 infrastructure SIP approvable without the
additional SO2 emission limitations showing in-state
attainment of the NAAQS, EPA finds the issues of appropriate averaging
periods for such future limitations not relevant at this time. The
Commenter has cited to prior EPA discussion on emission limitations
required in PSD permits (from an EAB decision and EPA's letter to
Kansas' permitting authority) pursuant to part C of the CAA, which is
neither relevant nor applicable to the present SIP action. In addition,
as previously discussed, the EPA disapproval of the 2006 Missouri SIP
was a disapproval relating to a control strategy SIP required pursuant
to part D attainment planning and is likewise not relevant to the
analysis of infrastructure SIP requirements.
---------------------------------------------------------------------------

    \22\ As EPA has stated, some areas are designated nonattainment
areas pursuant to CAA section 107 for the 2010 SO2 NAAQS
in the Commonwealth. Thus, while the Commonwealth, at this time, has
an obligation to submit attainment plans for the 2010 SO2
NAAQS for sections 172, 191 and 192, EPA believes the appropriate
time for examining necessity of the averaging periods within any
submitted SO2 emission limits on specific sources is
within the attainment planning process.
    \23\ For a discussion on emission averaging times for emissions
limitations for SO2 attainment SIPs, see the April 23,
2014 Guidance for 1-Hour SO2 Nonattainment Area SIP
Submissions. EPA explained that it is possible, in specific cases,
for states to develop control strategies that account for
variability in 1-hour emissions rates through emission limits with
averaging times that are longer than 1-hour, using averaging times
as long as 30-days, but still provide for attainment of the 2010
SO2 NAAQS as long as the limits are of at least
comparable stringency to a 1-hour limit at the critical emission
value. EPA has not yet evaluated any specific submission of such a
limit, and so is not at this time prepared to take final action to
implement this concept.
---------------------------------------------------------------------------

    Comment 9: The Commenter states that enforceable emission limits in
SIPs or permits are necessary to avoid nonattainment designations in
areas where modeling or monitoring shows SO2 levels exceed
the 1-hour SO2 NAAQS and cites to a February 6, 2013 EPA
document, Next Steps for Area Designations and Implementation of the
Sulfur Dioxide National Ambient Air Quality Standard, which the
Commenter contends discusses how states could avoid future
nonattainment designations. The Commenter asserts EPA must ensure
enforceable emission limits in the Pennsylvania infrastructure SIP will
not allow ``exceedances'' of the SO2 NAAQS. The Commenter
claims the modeling it conducted for Brunner Island, Montour, Cheswick,
New Castle, and Shawville indicates at least 28 additional counties in
Pennsylvania must be designated nonattainment with the 2010
SO2 NAAQS without such enforceable SO2 limits. In
summary, the Commenter asserts EPA must disapprove the Pennsylvania
infrastructure SIP and ensure emission limits will not allow large
sources of SO2 to cause exceedances of the 2010
SO2 NAAQS.
    Response 9: EPA appreciates the Commenter's concern with avoiding
nonattainment designations in Pennsylvania for the 2010 SO2
NAAQS. However, Congress designed the CAA such that states have the
primary responsibility for achieving and maintaining the NAAQS within
their geographic area by submitting SIPs which will specify the details
of how the state will meet the NAAQS. Pursuant to section 107(d), the
states make initial recommendations of designations for areas within
each state and EPA then promulgates the designations after considering
the state's submission and other information. EPA promulgated initial
designations for the 2010 SO2 NAAQS in August 2013 for areas
in which monitoring at that time showed violations of the NAAQS, but
has not yet issued designations for other areas and will complete the
required designations pursuant to the schedule contained in the
recently entered Consent Decree. EPA will designate additional areas
for the 2010 SO2 NAAQS in accordance with the CAA section
107 and existing EPA policy and guidance. Pennsylvania may, on its own
accord, decide to impose additional SO2 emission limitations
to avoid future designations to nonattainment. If additional
Pennsylvania areas are designated nonattainment, Pennsylvania will then
have the initial opportunity to develop additional emissions
limitations needed to attain the NAAQS, and EPA would be charged with
reviewing whether the SIP is adequate to demonstrate attainment. See
Commonwealth of Virginia, et al., v. EPA, 108 F.3d 1397, 1410 (D.C.
Cir. 1997) (citing Natural Resources Defense Council, Inc. v. Browner,
57 F.3d 1122, 1123 (DCCir.1995)) (discussing that states have primary
responsibility for determining an emission reductions program for its
areas subject to EPA approval dependent upon whether the SIP as a whole
meets applicable requirements of the CAA). However, such considerations
are not required of Pennsylvania at the infrastructure SIP stage of
NAAQS implementation, as the Commenter's statements concern the
separate designations process under section 107.\24\ EPA disagrees that
the

infrastructure SIP must be disapproved for not including enforceable
emissions limitations to prevent future 1-hour SO2
nonattainment designations.
---------------------------------------------------------------------------

    \24\ EPA also notes that in EPA's final rule regarding the 2010
SO2 NAAQS, EPA noted that it anticipates several
forthcoming national and regional rules, such as the Industrial
Boilers standard under CAA section 112, are likely to require
significant reductions in SO2 emissions over the next
several years. See 75 FR 35520. EPA continues to believe similar
national and regional rules will lead to SO2 reductions
that will help achieve compliance with the 2010 SO2
NAAQS. If it appears that states with areas designated nonattainment
in 2013 will nevertheless fail to attain the NAAQS as expeditiously
as practicable (but no later than October 2018) during EPA's review
of attainment SIPs required by section 172, the CAA provides
authorities and tools for EPA to solve such failure, including, as
appropriate, disapproving submitted SIPs and promulgating federal
implementation plans. Likewise, for any areas designated
nonattainment after 2013, EPA has the same authorities and tools
available to address any areas which do not timely attain the NAAQS.
---------------------------------------------------------------------------

D. Sierra Club Comments on Pennsylvania 2008 Ozone Infrastructure SIP

    Comment 10: The Commenter claims EPA must disapprove the proposed
infrastructure SIP for the 2008 ozone NAAQS for its failure to include
enforceable measures on sources of volatile organic compounds (VOCs)
and nitrogen oxides (NOX) to ensure attainment and
maintenance of the NAAQS in areas not designated nonattainment and to
ensure compliance with section 110(a)(2)(A) for the 2008 ozone NAAQS.
The Commenter specifically mentions EGUs as well as the oil and gas
production industry as sources needing additional controls as they are
major sources of ozone precursors. The Commenter claims stringent
emission limits must apply at all times to ensure all areas in
Pennsylvania attain and maintain the ozone NAAQS. The Commenter claims
the provisions listed by Pennsylvania for section 110(a)(2)(A) in its
2008 ozone NAAQS infrastructure SIP are insufficient for attaining and
maintaining the 2008 ozone NAAQS as evidenced by the Commenter's review
of air quality monitoring data in areas which are not presently
designated nonattainment for the 2008 ozone NAAQS. Specifically, the
Commenter cites air monitoring in a number of Pennsylvania counties
including Mercer, Indiana, Lebanon, Dauphin, Erie and York counties
indicating ``exceedances'' of the NAAQS and what the Commenter asserts
are design values above the NAAQS in 2010-2012, 2011-2013, and 2012-
2014. The Commenter alleges that these ``exceedances'' demonstrate that
the Pennsylvania 2008 ozone infrastructure SIP with existing
regulations, statutes, source-specific limits and programs fails to
demonstrate the infrastructure SIP will ensure attainment and
maintenance of the 2008 ozone NAAQS. Thus, the Commenter asserts EPA
must disapprove the 2008 ozone infrastructure SIP.
    In addition, the Commenter asserts that the infrastructure SIP
required by section 110(a) must provide assurances that the NAAQS will
be attained and maintained for areas not designated nonattainment and
asserts that the Pennsylvania infrastructure SIP must contain state-
wide regulations and emission limits that ``ensure that the proper mass
limitations and short term averaging periods are imposed on certain
specific large sources of NOX such as power plants. These
emission limits must apply at all times . . . to ensure that all areas
of Pennsylvania attain and maintain the 2008 eight-hour Ozone NAAQS.''
The Commenter suggests limits should be set on a pounds per hour (lbs/
hr) basis for EGUs to address variation in mass emissions and ensure
protection of the ambient air quality. The Commenter cites to
NOX limits from PSD permits issued to EGUs with low
NOX emission rates, claiming such rates and related control
efficiencies are achievable for EGUs. The Commenter suggests short-term
averaging limits would ensure EGUs cannot emit NOX at higher
rates on days when ozone levels are worst while meeting a longer-term
average. The Commenter also contends that adding control devices and
emission limits on EGUs are a ``cost effective option to reduce
NOX pollution and attain and maintain the 2008 ozone
NAAQS.''
    Finally, the Commenter contends the proposed ozone infrastructure
SIP cannot ensure Pennsylvania will attain and maintain the 2008 ozone
NAAQS and contends EPA must disapprove the SIP for lack of emission
limits to attain and maintain the ozone NAAQS statewide.
    Response 10: EPA disagrees with the commenter that the
infrastructure SIPs must include detailed attainment and maintenance
plans for all areas of the state and must be disapproved if ozone air
quality data that became available late in the process or after the SIP
was due and submitted changes the status of areas within the state.\25\
EPA has addressed in detail in prior responses above the Commenter's
general arguments that the statutory language, legislative history,
case law, EPA regulations, and prior rulemaking actions by EPA mandate
the interpretation it advocates--i.e., that infrastructure SIPs must
ensure attainment and maintenance of the NAAQS. EPA believes that
section 110(a)(2)(A) is reasonably interpreted to require states to
submit SIPs that reflect the first step in their planning for attaining
and maintaining a new or revised NAAQS and that they contain
enforceable control measures and a demonstration that the state has the
available tools and authority to develop and implement plans to attain
and maintain the NAAQS, including the 2008 ozone NAAQS.
---------------------------------------------------------------------------

    \25\ EPA notes however that the data presented by the Commenter
in table 5 of its March 9, 2015 comments indicates a general
improving trend in ozone air quality for the specific counties the
Commenter included. The data could equally be used to indicate
improving ozone air quality based on existing measures in the
Pennsylvania SIP.
---------------------------------------------------------------------------

    Moreover, the CAA recognizes and has provisions to address changes
in air quality over time, such as an area slipping from attainment to
nonattainment or changing from nonattainment to attainment. These
include provisions providing for redesignation in section 107(d) and
provisions in section 110(k)(5) allowing EPA to call on the state to
revise its SIP, as appropriate.
    The Commenter suggests that EPA must disapprove the Pennsylvania
ozone infrastructure SIP because the fact that a few areas in
Pennsylvania recently had air quality data slightly above the standard
therefore proves that the infrastructure SIP is inadequate to
demonstrate maintenance of the ozone NAAQS for those areas. EPA
disagrees with the Commenter because EPA does not believe that section
110(a)(2)(A) requires detailed planning SIPs demonstrating either
attainment or maintenance for specific geographic areas of the state.
The infrastructure SIP is triggered by promulgation of the NAAQS, not
designation. Moreover, infrastructure SIPs are due three years
following promulgation of the NAAQS and designations are not due until
two years (or in some cases three years) following promulgation of the
NAAQS. Thus, during a significant portion of the period that a state
has available for developing the infrastructure SIP, it does not know
what the designation will be for individual areas of the state.\26\ In
light of the structure of the CAA, EPA's long-standing position
regarding infrastructure SIPs is that they are general planning SIPs to
ensure that the state has adequate resources and

authority to implement a NAAQS in general throughout the state and not
detailed attainment and maintenance plans for each individual area of
the state.
---------------------------------------------------------------------------

    \26\ While it is true that there may be some monitors within a
state with values so high as to make a nonattainment designation of
the county with that monitor almost a certainty, the geographic
boundaries of the nonattainment area associated with that monitor
would not be known until EPA issues final designations. Moreover,
the five areas of concern to the Commenter do not fit that
description in any event.
---------------------------------------------------------------------------

    EPA's interpretation that infrastructure SIPs are more general
planning SIPs is consistent with the statute as understood in light of
its history and structure as explained previously in response to prior
comments. While at one time section 110 did provide the only detailed
SIP planning provisions for states and specified that such plans must
provide for attainment of the NAAQS, part D of title I of the CAA (not
CAA section 110) governs the substantive planning process, including
planning for attainment and maintenance of the NAAQS.
    For the reasons explained by EPA in this action, EPA disagrees with
the Commenter that EPA must disapprove an infrastructure SIP revision
if there are monitored violations of the standard in the state and the
section 110(a)(2)(A) revision does not have detailed plans for
demonstrating how the state will bring that area into attainment or
ensure maintenance of the NAAQS. Rather, EPA believes that the proper
inquiry at this juncture is whether the state has met the basic
structural SIP requirements appropriate at the point in time EPA is
acting upon the submittal. EPA's NPR and TSD for this rulemaking
address why the Pennsylvania SIP meets the basic structural SIP
requirements as to the elements addressed in section 110(a)(2) in the
NPR for the 2008 ozone NAAQS.
    As addressed in EPA's proposed approval for this rule, Pennsylvania
submitted a list of existing emission reduction measures in the SIP
that control emissions of NOX and VOCs. Pennsylvania's SIP
revision reflects numerous provisions that have the ability to reduce
ground level ozone and its precursors. The Pennsylvania SIP relies on
measures and programs used to implement previous ozone NAAQS. Because
there is no substantive difference between the previous ozone NAAQS and
the more recent ozone NAAQS, other than the level of the standard, the
provisions relied on by Pennsylvania will provide benefits for the new
NAAQS; in other words, the measures reduce overall ground-level ozone
and its precursors and are not limited to reducing ozone levels to meet
one specific NAAQS. Although additional control measures for ozone
precursors such as those mentioned by the Commenter may be considered
by PADEP and could be submitted with an infrastructure SIP, these
additional measures are not a requirement in order for Pennsylvania to
meet CAA section 110(a)(2)(A). In approving Pennsylvania's
infrastructure SIP revision, EPA is affirming that Pennsylvania has
sufficient authority to take the types of actions required by the CAA
in order to bring such areas back into attainment.
    Finally, EPA appreciates the Commenter's information regarding EGU
NOX control measures and reduction efficiencies as well as
emissions limitations applicable to new or modified EGUs which were set
during the PSD or NSR permit process. Additional NOX
regulations on emissions from EGUs would likely reduce ozone levels
further in one or more areas in Pennsylvania. Congress established the
CAA such that each state has primary responsibility for assuring air
quality within the state and each state is first given the opportunity
to determine an emission reduction program for its areas subject to EPA
approval, with such approval dependent upon whether the SIP as a whole
meets the applicable requirements of the CAA. See Virginia v. EPA, 108
F.3d at 1410. The Commonwealth could choose to consider additional
control measures for NOX at EGUs to ensure attainment and
maintenance of the ozone NAAQS as Pennsylvania moves forward to meet
the more prescriptive planning requirements of the CAA in the future.
However, as we have explained, the Commonwealth is not required to
regulate such sources for purposes of meeting the infrastructure SIP
requirements of CAA section 110(a)(2).
    In addition, emission limits with the shorter-term averaging rates
suggested by the Commenter could be considered within the part D
planning process to ensure attainment and maintenance of the 2008 ozone
NAAQS. As EPA finds Pennsylvania's NOX and VOC provisions
presently in the SIP sufficient for infrastructure SIP purposes and
specifically for CAA section 110(a)(2)(A), further consideration of
averaging times is not appropriate or relevant at this time. Thus, EPA
disagrees with the Commenter that Pennsylvania's ozone infrastructure
SIP must be disapproved for failure to contain sufficient measures to
ensure attainment and maintenance of the NAAQS.
    Comment 11: The Commenter states enforceable emission limits are
necessary to avoid future nonattainment designations in areas where
Pennsylvania's monitoring network has shown ``exceedances'' with the
2008 ozone NAAQS in recent years. The Commenter stated EPA must address
inadequacies in enforceable emission limitations relied upon by
Pennsylvania for its ozone infrastructure SIP to comply with CAA
section 110(a)(2)(A) and stated EPA must disapprove the ozone
infrastructure SIP to ensure large sources of NOX and VOCs
cannot contribute to exceedances of the ozone NAAQS and prohibit
attainment and maintenance of the ozone NAAQS in all of Pennsylvania.
    Response 11: For the reasons previously discussed, EPA disagrees
with the Commenter that we must disapprove the Pennsylvania ozone
infrastructure SIP because it does not demonstrate how areas that may
be newly violating the ozone NAAQS since the time of designation can be
brought back into attainment. Enforceable emission limitations to avoid
future nonattainment designations are not required for EPA to approve
an infrastructure SIP under CAA section 110, and any emission
limitations needed to assure attainment and maintenance with the ozone
NAAQS will be determined by Pennsylvania and reviewed by EPA as part of
the part D attainment SIP planning process. Thus, EPA disagrees with
the Commenter that EPA must disapprove the ozone infrastructure SIP to
ensure large sources of NOX and VOC do not contribute to
exceedances of the NAAQS or prohibit implementation, attainment or
maintenance of the ozone NAAQS. As explained in the NPR and TSD,
Pennsylvania has sufficient emission limitations and measures to
address NOX and VOC emissions for CAA section 110(a)(2)(A).

III. Final Action

    EPA is approving the following elements of Pennsylvania's June 15,
2014 SIP revisions for the 2008 ozone NAAQS and the 2010 SO2
NAAQS: Section 110(a)(2)(A), (B), (C), (D)(i)(II) (PSD requirements),
(D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M). Pennsylvania's SIP
revisions provide the basic program elements specified in Section
110(a)(2) necessary to implement, maintain, and enforce the 2008 ozone
NAAQS and the 2010 SO2 NAAQS. This final rulemaking action
does not include action on section 110(a)(2)(I) which pertains to the
nonattainment planning requirements of part D, Title I of the CAA,
because this element is not required to be submitted by the 3-year
submission deadline of section 110(a)(1) of the CAA, and will be
addressed in a separate process. This final rulemaking action also does
not include action on section 110(a)(2)(D)(i)(I) for interstate
transport for the 2008 ozone or the 2010 SO2 NAAQS as
Pennsylvania's July 15,

2014 SIP submissions did not address this element for either NAAQS nor
does this rulemaking include any action on section 110(a)(2)(D)(i)(II)
for visibility protection for either NAAQS. While Pennsylvania's July
15, 2014 SIP submissions for the 2008 ozone and 2010 SO2
NAAQS included provisions addressing visibility protection, EPA will
take later, separate action on this element for both of these NAAQS.

IV. Statutory and Executive Order Reviews

A. General Requirements

    Under the CAA, the Administrator is required to approve a SIP
submission that complies with the provisions of the CAA and applicable
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
action merely approves state law as meeting Federal requirements and
does not impose additional requirements beyond those imposed by state
law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to
review by the Office of Management and Budget under Executive Order
12866 (58 FR 51735, October 4, 1993);
     does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     is certified as not having a significant economic impact
on a substantial number of small entities under the Regulatory
Flexibility Act (5 U.S.C. 601 et seq.);
     does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
     does not have Federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
     is not an economically significant regulatory action based
on health or safety risks subject to Executive Order 13045 (62 FR
19885, April 23, 1997);
     is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001);
     is not subject to requirements of Section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the CAA; and
     does not provide EPA with the discretionary authority to
address, as appropriate, disproportionate human health or environmental
effects, using practicable and legally permissible methods, under
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, this rule does not have tribal implications as
specified by Executive Order 13175 (65 FR 67249, November 9, 2000),
because the SIP is not approved to apply in Indian country located in
the state, and EPA notes that it will not impose substantial direct
costs on tribal governments or preempt tribal law.

B. Submission to Congress and the Comptroller General

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this action and
other required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of the rule in the Federal Register. A major rule cannot
take effect until 60 days after it is published in the Federal
Register. This action is not a ``major rule'' as defined by 5 U.S.C.
804(2).

C. Petitions for Judicial Review

    Under section 307(b)(1) of the CAA, petitions for judicial review
of this action must be filed in the United States Court of Appeals for
the appropriate circuit by October 5, 2015. Filing a petition for
reconsideration by the Administrator of this final rule does not affect
the finality of this action for the purposes of judicial review nor
does it extend the time within which a petition for judicial review may
be filed, and shall not postpone the effectiveness of such rule or
action.
    This action pertaining to Pennsylvania's section 110(a)(2)
infrastructure elements for the 2008 ozone NAAQS and 2010
SO2 NAAQS may not be challenged later in proceedings to
enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen dioxide, Ozone,
Reporting and recordkeeping requirements, Sulfur oxides, Volatile
organic compounds.

    Dated: July 24, 2015.
William C. Early,
Acting Regional Administrator, Region III.

    40 CFR part 52 is amended as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

     Authority: 42 U.S.C. 7401 et seq.

Subpart NN--Pennsylvania

0
2. In Sec.  52.2020, the table in paragraph (e)(1) is amended by adding
two entries for ``Section 110(a)(2) Infrastructure Requirements for the
2008 ozone NAAQS'' and ``Section 110(a)(2) Infrastructure Requirements
for the 2010 SO2 NAAQS'' at the end of the table to read as
follows:

Sec.  52.2020  Identification of plan.

* * * * *
    (e) * * *
    (1) * * *

----------------------------------------------------------------------------------------------------------------
                                                          State
   Name of non-regulatory SIP          Applicable       submittal    EPA Approval date    Additional explanation
            revision                geographic area        date
----------------------------------------------------------------------------------------------------------------

                                                  * * * * * * *
Section 110(a)(2) Infrastructure  Statewide..........      7/15/14  8/5/15 [Insert       This rulemaking action
 Requirements for the 2008 ozone                                     Federal Register     addresses the
 NAAQS.                                                              citation].           following CAA
                                                                                elements:
                                                                                110(a)(2)(A), (B),
                                                                                (C), (D)(i)(II)
                                                                                (prevention of
                                                                                significant
                                                                                deterioration),
                                                                                (D)(ii), (E), (F),
                                                                                (G), (H), (J), (K),
                                                                                (L), and (M).
Section 110(a)(2) Infrastructure  Statewide..........      7/15/14  8/5/15 [Insert       This rulemaking action
 Requirements for the 2010 SO2                                       Federal Register     addresses the
 NAAQS.                                                              citation].           following CAA
                                                                                elements:
                                                                                110(a)(2)(A), (B),
                                                                                (C), (D)(i)(II)
                                                                                (prevention of
                                                                                significant
                                                                                deterioration),
                                                                                (D)(ii), (E), (F),
                                                                                (G), (H), (J), (K),
                                                                                (L), and (M).
----------------------------------------------------------------------------------------------------------------

[FR Doc. 2015-19090 Filed 8-4-15; 8:45 am]
 BILLING CODE 6560-50-P