[Federal Register Volume 78, Number 139 (Friday, July 19, 2013)]
[Proposed Rules]
[Pages 43096-43115]
[FR Doc No: 2013-17430]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R01-OAR-2013-0020; FRL-9834-7]

Approval and Promulgation of Air Quality Implementation Plans;
Connecticut; Redesignation of Connecticut Portion of the New York-New
Jersey-Connecticut Nonattainment Area to Attainment of the 1997 Annual
and 2006 24-Hour Standards for Fine Particulate Matter

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing to approve the State of Connecticut's June
22, 2012 request to redesignate the Connecticut portion of the New
York-N. New Jersey-Long Island, NY-NJ-CT fine particle
(PM2.5) area (i.e., New Haven and Fairfield Counties; herein
called the ``Southwestern CT Area'' or ``the Area'') from nonattainment
to attainment for the 1997 annual National Ambient Air Quality
Standards (NAAQS or standard), as well as for the 2006 24-hour
PM2.5 NAAQS. As part of these proposed approvals, EPA
proposes to approve (1) a State Implementation Plan (SIP) revision
containing a 10-year maintenance plan for the Area; (2) a 2007 base-
year emissions inventory for the Area; and (3) new motor vehicle
emissions budgets (MVEBs) for the years 2017 and 2025 that are
contained in the 10-year PM2.5 maintenance plan for the
Area.
    In addition, in the course of proposing to approve Connecticut's
request to redesignate the Southwestern CT Area, EPA addresses a number
of additional issues, including the effects of two decisions of the
United States Court of Appeals for the District of Columbia (D.C.
Circuit Court): (1) The Court's August 21, 2012 decision to vacate and
remand to EPA the Cross-State Air Pollution Control Rule (CSAPR), and
(2) the Court's January 4, 2013 decision to remand to EPA two final
rules implementing the 1997 PM2.5 standard.
    This action is being taken in accordance with the Clean Air Act
(CAA).

DATES: Written comments must be received on or before August 19, 2013.

ADDRESSES: Submit your comments, identified by Docket ID Number EPA-
R01-OAR-2013-0020 by one of the following methods:
    1. www.regulations.gov: Follow the on-line instructions for
submitting comments.
    2. Email<EMAIL_ADDRESS>    3. Fax:<PHONE_NUMBER>.
    4. Mail: ``Docket Identification Number EPA-R01-OAR-2013-0020,''
Anne Arnold, U.S. Environmental Protection Agency, EPA New England
Regional Office, 5 Post Office Square, Suite 100 (mail code: OEP05-2),
Boston, MA 02109-3912.
    5. Hand Delivery or Courier. Deliver your comments to: Anne Arnold,
Manager, Air Quality Planning Unit, Office of Ecosystem Protection,
U.S. Environmental Protection Agency, EPA New England Regional Office,
5 Post Office Square, Suite 100, Boston, MA 02109-3912. Such deliveries
are only

accepted during the Regional Office's normal hours of operation. The
Regional Office's official hours of business are Monday through Friday,
8:30 to 4:30, excluding legal holidays.
    Instructions: Direct your comments to Docket ID No. EPA-R01-OAR-
2013-0020. EPA's policy is that all comments received will be included
in the public docket without change and may be made available online at
www.regulations.gov, including any personal information provided,
unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit through www.regulations.gov or
email, information that you consider to be CBI or otherwise protected.
The www.regulations.gov Web site is an ``anonymous access'' systems,
which means EPA will not know your identity or contact information
unless you provide it in the body of your comment. If you send an email
comment directly to EPA without going through www.regulations.gov, your
email address will be automatically captured and included as part of
the comment that is placed in the public docket and made available on
the Internet. If you submit an electronic comment, EPA recommends that
you include your name and other contact information in the body of your
comment and with any disk or CD-ROM you submit. If EPA cannot read your
comment due to technical difficulties and cannot contact you for
clarification, EPA may not be able to consider your comment. Electronic
files should avoid the use of special characters, any form of
encryption, and be free of any defects or viruses. For additional
information about EPA's public docket visit the EPA Docket Center
homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the electronic docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, i.e., 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 in www.regulations.gov or
in hard copy at Air Quality Planning Unit, Office of Ecosystem
Protection, U.S. Environmental Protection Agency, EPA New England
Regional Office, Office of Ecosystem Protection, Air Quality Planning
Unit, 5 Post Office Square--Suite 100, Boston, MA. EPA requests that if
at all possible, you contact the person listed in the FOR FURTHER
INFORMATION CONTACT section to schedule your inspection. The Regional
Office's official hours of business are Monday through Friday, 8:30 to
4:30, excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: Alison C. Simcox, Air Quality Planning
Unit, U.S. Environmental Protection Agency, EPA New England Regional
Office, Office of Ecosystem Protection, Air Quality Planning Unit, 5
Post Office Square--Suite 100, (Mail code OEP05-2), Boston, MA 02109--
3912, telephone number<PHONE_NUMBER>, fax number<PHONE_NUMBER>, email
<EMAIL_ADDRESS>    In addition to the publicly available docket materials available
for inspection electronically in the Federal Docket Management System
at www.regulations.gov, and the hard copy available at the Regional
Office, which are identified in the ADDRESSES section of this Federal
Register, copies of the state submittal are also available for public
inspection during normal business hours, by appointment at the State
Air Agency: Bureau of Air Management, Department of Energy and
Environmental Protection, State Office Building, 79 Elm Street,
Hartford, CT 06106-1630.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,''
``us,'' or ``our'' is used, we mean EPA.

Table of Contents

I. What should I consider as I prepare my comments for EPA?
II. What is the background for the proposal?
    A. General Background
    B. Effect of the August 21, 2012 D.C. Circuit Decision Regarding
EPA's CSAPR
    C. Effect of the January 4, 2013 D.C. Circuit Decision Regarding
PM2.5 Implementation Under Subpart 4
    1. Background
    2. Proposal on This Issue
    a. Applicable Requirements for Purposes of Evaluating the
Redesignation Request
    b. Subpart 4 Requirements and Connecticut's Redesignation
Request
    c. Subpart 4 and Control of PM2.5 Precursors
    d. Maintenance Plan and Evaluation of Precursors
III. What are the criteria for redesignation to attainment?
IV. What is EPA's analysis of the State's request?
    A. Has the Southwestern CT Area attained the 1997
PM2.5 NAAQS?
    B. Has the Southwestern CT Area attained the 2006
PM2.5 NAAQS?
    C. Has the State of Connecticut met all applicable requirements
of Section 110 and Part D and does the Southwestern CT Area have a
fully approved SIP under Section 110(k) of the CAA for purposes of
redesignation to attainment?
    1. Section 110 and General SIP Requirements
    2. Part D SIP Requirements
    3. Does the Southwestern CT Area have a fully approved
applicable SIP under Section 110(k) of the CAA?
    D. Are the air quality improvements in the Southwestern CT Area
due to permanent and enforceable reductions in emissions?
    1. Federal Measures Implemented
    2. SIP-Approved State Measures
    E. Does the Southwestern CT Area have a fully approved
maintenance plan pursuant to Section 175a of the CAA?
    1. Maintenance Plan Requirements
    2. EPA's Analysis of the Southwestern CT Area Maintenance Plan
    a. Attainment Emissions Inventory
    b. Maintenance Demonstration
    c. Monitoring Network
    d. Verification of Continued Attainment
    e. The Maintenance Plan's Contingency Measures
V. MVEBs
    1. How are MVEBs developed and what are the MVEBs for the
Southwestern CT Area?
    2. What are safety margins?
VI. Proposed Actions
VII. Statutory and Executive Order Reviews

I. What should I consider as I prepare my comments for EPA?

    When submitting comments, remember to:
    1. Identify the rulemaking by docket number and other identifying
information (subject heading, Federal Register date, and page number).
    2. Follow directions--EPA may ask you to respond to specific
questions or organize comments by referencing a Code of Federal
Regulations (CFR) part or section number.
    3. Explain why you agree or disagree; suggest alternatives and
substitute language for your requested changes.
    4. Describe any assumptions and provide any technical information
and/or data that you used.
    5. If you estimate potential costs or burdens, explain how you
arrived at your estimate in sufficient detail to allow for it to be
reproduced.
    6. Provide specific examples to illustrate your concerns, and
suggest alternatives.
    7. Explain your views as clearly as possible, avoiding the use of
profanity or personal threats.
    8. Make sure to submit your comments by the comment period deadline
identified.

II. What is the background for the proposal?

A. General Background

    On June 22, 2012, the Connecticut Department of Energy and
Environmental Protection (CT DEEP)

submitted a request to EPA to redesignate the Connecticut portion of
the New York-N. New Jersey-Long Island, NY-NJ-CT fine particle
(PM2.5) area (the Southwestern CT Area comprising New Haven
and Fairfield Counties) to attainment for the 1997 annual and 2006 24-
hour PM2.5 NAAQS, and for EPA approval of the state
implementation plan (SIP) revision containing an emissions inventory
and a maintenance plan for the area.
    Fine particulate pollution is emitted directly from a source
(primary PM2.5) or is formed secondarily through chemical
reactions in the atmosphere involving precursor pollutants (nitrogen
oxides (NOX), sulfur dioxides (SO2), volatile
organic compounds (VOC), and ammonia (NH3)) emitted from a
variety of sources. For example, sulfates are formed from
SO2 emissions from power plants and industrial facilities.
Nitrates are formed from combustion emissions of NOX from
power plants, mobile sources, and other combustion sources.
    The CAA establishes a process for air-quality management through
the NAAQS. The first air quality standards for PM2.5 were
promulgated on July 18, 1997 (62 FR 38652). EPA promulgated an annual
standard at a level of 15 micrograms per cubic meter ([micro]g/m\3\) of
ambient air, based on a three-year average of the annual mean
PM2.5 concentrations at each monitoring site. In the same
rulemaking, EPA promulgated a 24-hour PM2.5 standard of 65
[micro]g/m\3\, based on a three-year average of the annual 98th
percentile of 24-hour concentrations at each monitoring site.
    On January 5, 2005 (70 FR 944), EPA designated the New York-N. New
Jersey-Long Island, NY-NJ-CT area (also referred to as the New York
Metropolitan Area), which includes the Southwestern CT Area, as
nonattainment for the 1997 PM2.5 NAAQS. See 70 FR 944 for a
listing of all counties included in the tri-state nonattainment area.
    On October 17, 2006 (71 FR 61144), EPA issued the 2006
PM2.5 NAAQS. The 2006 NAAQS retained the annual
PM2.5 standard at 15 [micro]g/m\3\, but revised the 24-hour
standard to 35 [micro]g/m\3\, based on a three-year average of the
annual 98th percentile of the 24-hour PM2.5 concentrations.
However, petitioners challenged EPA's decision to retain the annual
standard (but did not challenge the 2006 24-hour PM2.5
standard). On February 24, 2009, the U.S. Court of Appeals for the D.C.
Circuit remanded the annual PM2.5 standard to the Agency for
reconsideration. See American Farm Bureau Federation and National Pork
Producers Council, et al. v. EPA, 559 F.3d 512 (D.C. Cir. 2009).
    On November 13, 2009 (74 FR 58688), EPA published designations for
the 24-hour standard established in 2006, designating the same New York
Metropolitan Area (including the Southwestern CT Area) as nonattainment
for this standard. In the November 2009 action, EPA clarified the
designations for the NAAQS promulgated in 1997, stating that the New
York Metropolitan Area remained designated nonattainment for the 1997
annual PM2.5 NAAQS, but was designated attainment for the
1997 24-hour NAAQS. Therefore, today's action does not address
attainment of the 1997 24-hour PM2.5 NAAQS.
    Today's action also does not address attainment of the remanded
2006 annual standard. However, given that the 1997 and 2006 annual
standards are essentially identical, attainment of the 1997 annual
standard would also indicate attainment of the remanded 2006 annual
standard. Therefore, today's action addresses attainment of the 1997
annual standard and the 2006 24-hour standard.
    On November 15, 2010, EPA determined that the entire New York
Metropolitan Area had attained the 1997 annual PM2.5
standard (75 FR 69589). This determination of attainment was based upon
complete, quality-assured and certified ambient air-quality data for
the 2007-2009 monitoring period. Subsequently, on December 31, 2012,
EPA determined that the entire New York Metropolitan Area had also
attained the 2006 24-hour PM2.5 standard (77 FR 76867). This
determination of attainment was based upon complete, quality-assured
and certified ambient air-quality data for the 2007-2009, 2008-2010,
and 2009-2011 monitoring periods. In addition, PM2.5
monitoring data for 2012 indicate continued attainment of both
standards. These determinations of attainment suspended the
requirements for Connecticut to submit an attainment demonstration,
associated reasonably available control measures, reasonable further
progress (RFP), contingency measures, and other planning SIPs related
to attainment of the 1997 annual or 2006 24-hour PM2.5 NAAQS
for as long as the Southwestern CT Area continues to attain these
standards.
    The CT DEEP redesignation request includes a maintenance plan
designed to ensure continued compliance with both the 1997 annual and
2006 24-hour PM2.5 standards through the year 2025. On
December 14, 2012, EPA issued a new annual standard of 12 [micro]g/
m\3\. Today's action does not address the 2012 standard.

B. Effect of the August 21, 2012 D.C. Circuit Decision Regarding EPA's
CSAPR

    On May 12, 2005, EPA published the Clean Air Interstate Rule
(CAIR), which requires significant reductions in emissions of
SO2 and NOX from electric generating units (EGUs)
to limit the interstate transport of these pollutants and the ozone and
fine particulate matter they form in the atmosphere. See 76 FR 70093.
The D.C. Circuit Court initially vacated CAIR, North Carolina v. EPA,
531 F.3d 896 (D.C. Cir. 2008), but ultimately remanded that rule to EPA
without vacatur to preserve the environmental benefits provided by
CAIR, North Carolina v. EPA, 550 F.3d 1176, 1178 (D.C. Cir. 2008).
    The Cross State Air Pollution Rule (CSAPR) included regulatory
changes to sunset (i.e., discontinue) CAIR and the CAIR Federal
Implementation Plans (FIPs) for control periods in 2012 and beyond. See
76 FR 48322. On December 30, 2011, the D.C. Circuit issued an order
addressing the status of CSAPR and CAIR in response to motions filed by
numerous parties seeking a stay of CSAPR pending judicial review. In
that order, the Court stayed CSAPR pending resolution of the petitions
for review of that rule in EME Homer City Generation, L.P. v. EPA (No.
11-1302 and consolidated cases). The Court also indicated that EPA was
expected to continue to administer CAIR in the interim until judicial
review of CSAPR was completed.
    On August 21, 2012, the D.C. Circuit issued EME Homer City
Generation, L.P. v. EPA, 696 F.3d 7 (D.C. Cir. 2012), which vacated and
remanded CSAPR and ordered EPA to continue administering CAIR ``pending
. . . development of a valid replacement.'' EME Homer City at 38. The
D.C. Circuit denied all petitions for rehearing on January 24, 2013. On
March 29, 2013, the U.S. Solicitor General petitioned the Supreme Court
to review the D.C. Circuit Court's decision on CSAPR. On June 24, 2013,
the Supreme Court granted the petition to review the decision. The
Supreme Court's decision to review the case does not alter the current
status of CAIR or CSAPR.
    Connecticut's submittal and EPA modeling demonstrate that
attainment of the 1997 annual and 2006 24-hour PM2.5
standards will be maintained with or without the implementation of CAIR
or CSAPR. To the extent that attainment is due to emission reductions
associated with CAIR, EPA is here determining that those reductions are
sufficiently

permanent and enforceable for purposes of CAA sections
107(d)(3)(E)(iii) and 175A.
    As directed by the D.C. Circuit, CAIR remains in place and
enforceable until EPA promulgates a valid replacement rule to
substitute for CAIR. Connecticut's SIP revision lists CAIR as a control
measure (Regulations of Connecticut State Agencies (RCSA) section 22a-
174-22c) that was adopted by the State in September 2007 with an
effective date of May 1, 2009. CAIR was, thus, in place and achieving
emission reductions when the New York Metropolitan Area began
monitoring attainment of the 1997 annual PM2.5 standard
during the 2007-2009 period, and of the 2006 24-hour PM2.5
standards during the same period. The quality-assured, certified
monitoring data continues to show the area in attainment with the 1997
and 2006 PM2.5 standards through 2012.
    In addition, modeling conducted by EPA during the CSAPR rulemaking
process also demonstrates that the Southwestern CT Area will have
PM2.5 levels below the 1997 annual and 2006 24-hour
PM2.5 standards in both 2012 and 2014 without taking into
account emissions reductions from CAIR or CSAPR. See ``Air Quality
Modeling Final Rule Technical Support Document'', App. B, B-18, B-19.
This modeling is available in the docket for this proposed
redesignation action.
    In sum, neither the current status of CAIR nor the current status
of CSAPR affects any of the criteria for proposed approval of this
redesignation request for the Southwestern CT Area.

C. Effect of the January 4, 2013 D.C. Circuit Decision Regarding
PM2.5 Implementation Under Subpart 4

1. Background
    As discussed above, on January 4, 2013, in Natural Resources
Defense Council v. EPA, the D.C. Circuit remanded to EPA the ``Final
Clean Air Fine Particle Implementation Rule'' (72 FR 20586, April 25,
2007) and the ``Implementation of the New Source Review (NSR) Program
for Particulate Matter Less than 2.5 Micrometers (PM2.5)''
final rule (73 FR 28321, May 16, 2008) (collectively, ``1997
PM2.5 Implementation Rule''). 706 F.3d 428 (D.C. Cir. 2013).
The Court found that EPA erred in implementing the 1997
PM2.5 NAAQS pursuant to the general implementation
provisions of subpart 1 of Part D of Title I of the CAA, rather than
the particulate-matter-specific provisions of subpart 4 of Part D of
Title I. Although the Court's ruling did not directly address the 2006
PM2.5 standard, EPA is taking into account the Court's
position on subpart 4 and the 1997 PM2.5 standard in
evaluating redesignations for the 2006 standard.
2. Proposal on This Issue
    EPA is proposing to determine that the Court's January 4, 2013
decision does not prevent EPA from redesignating the Southwestern CT
Area to attainment. Even in light of the Court's decision,
redesignation for this area is appropriate under the CAA and EPA's
longstanding interpretations of the CAA's provisions regarding
redesignation. EPA first explains its longstanding interpretation that
requirements that are imposed, or that become due, after a complete
redesignation request is submitted for an area that is attaining the
standard, are not applicable for purposes of evaluating a redesignation
request. Second, EPA then shows that, even if EPA applies the subpart 4
requirements to Connecticut's redesignation request and disregards the
provisions of its 1997 PM2.5 implementation rule recently
remanded by the Court, the state's request for redesignation of this
area still qualifies for approval. EPA's discussion takes into account
the effect of the Court's ruling on the area's maintenance plan, which
EPA views as approvable when subpart 4 requirements are considered.
a. Applicable Requirements for Purposes of Evaluating the Redesignation
Request
    With respect to the 1997 PM2.5 Implementation Rule, the
Court's January 4, 2013 ruling rejected EPA's reasons for implementing
the PM2.5 NAAQS solely in accordance with the provisions of
subpart 1, and remanded that matter to EPA, so that it could address
implementation of the 1997 PM2.5 NAAQS under subpart 4 of
Part D of the CAA, in addition to subpart 1. For the purposes of
evaluating Connecticut's redesignation request for the Southwestern CT
Area, to the extent that implementation under subpart 4 would impose
additional requirements for areas designated nonattainment, EPA
believes that those requirements are not ``applicable'' for the
purposes of CAA section 107(d)(3)(E), and, thus, EPA is not required to
consider subpart 4 requirements with respect to this redesignation
request. Under its longstanding interpretation of the CAA, EPA has
interpreted section 107(d)(3)(E) to mean, as a threshold matter, that
the part D provisions which are ``applicable'' and which must be
approved in order for EPA to redesignate an area include only those
which came due prior to a state's submittal of a complete redesignation
request. See ``Procedures for Processing Requests to Redesignate Areas
to Attainment,'' Memorandum from John Calcagni, Director, Air Quality
Management Division, September 4, 1992 (Calcagni memorandum). See also
``State Implementation Plan (SIP) Requirements for Areas Submitting
Requests for Redesignation to Attainment of the Ozone and Carbon
Monoxide (CO) National Ambient Air Quality Standards (NAAQS) on or
after November 15, 1992,'' Memorandum from Michael Shapiro, Acting
Assistant Administrator, Air and Radiation, September 17, 1993 (Shapiro
memorandum); Final Redesignation of Detroit-Ann Arbor, (60 FR 12459,
12465-66, March 7, 1995); Final Redesignation of St. Louis, Missouri,
(68 FR 25418, 25424-27, May 12, 2003); Sierra Club v. EPA, 375 F.3d
537, 541 (7th Cir. 2004) (upholding EPA's redesignation rulemaking
applying this interpretation and expressly rejecting Sierra Club's view
that the meaning of ``applicable'' under the statute is ``whatever
should have been in the plan at the time of attainment rather than
whatever actually was in the plan and already implemented or due at the
time of attainment'').\1\ In this case, at the time that Connecticut
submitted its redesignation request, requirements under subpart 4 were
not due.
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    \1\ Applicable requirements of the CAA that come due subsequent
to the area's submittal of a complete redesignation request remain
applicable until a redesignation is approved, but are not required
as a prerequisite to redesignation. Section 175A(c) of the CAA.
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    EPA's view that, for purposes of evaluating the Southwestern CT
Area redesignation, the subpart 4 requirements were not due at the time
the State submitted the redesignation request is in keeping with the
EPA's interpretation of subpart 2 requirements for subpart 1 ozone
areas redesignated subsequent to the D.C. Circuit's decision in South
Coast Air Quality Mgmt. Dist. v. EPA, 472 F.3d 882 (D.C. Cir. 2006). In
South Coast, the Court found that EPA was not permitted to implement
the 1997 8-hour ozone standard solely under subpart 1, and held that
EPA was required under the statute to implement the standard under the
ozone-specific requirements of subpart 2 as well. Subsequent to the
South Coast decision, in evaluating and acting upon redesignation
requests for the 1997 8-hour ozone standard that were submitted to EPA
for areas under subpart 1, EPA applied its longstanding interpretation
of the CAA that ``applicable requirements,'' for purposes

of evaluating a redesignation, are those that had been due at the time
the redesignation request was submitted. See, e.g., Proposed
Redesignation of Manitowoc County and Door County Nonattainment Areas
(75 FR 22047, 22050, April 27, 2010). In those actions, EPA therefore
did not consider subpart 2 requirements to be ``applicable'' for the
purposes of evaluating whether the area should be redesignated under
section 107(d)(3)(E).
    EPA's interpretation derives from the provisions of CAA Section
107(d)(3). Section 107(d)(3)(E)(v) states that, for an area to be
redesignated, a state must meet ``all requirements `applicable' to the
area under section 110 and part D.'' Section 107(d)(3)(E)(ii) provides
that the EPA must have fully approved the ``applicable'' SIP for the
area seeking redesignation. These two sections read together support
EPA's interpretation of ``applicable'' as only those requirements that
came due prior to submission of a complete redesignation request.
First, holding states to an ongoing obligation to adopt new CAA
requirements that arose after the state submitted its redesignation
request, in order to be redesignated, would make it problematic or
impossible for EPA to act on redesignation requests in accordance with
the 18-month deadline Congress set for EPA action in section
107(d)(3)(D). If ``applicable requirements'' were interpreted to be a
continuing flow of requirements with no reasonable limitation, states,
after submitting a redesignation request, would be forced continuously
to make additional SIP submissions that in turn would require EPA to
undertake further notice-and-comment rulemaking actions to act on those
submissions. This would create a regime of unceasing rulemaking that
would delay action on the redesignation request beyond the 18-month
timeframe provided by the Act for this purpose.
    Second, a fundamental premise for redesignating a nonattainment
area to attainment is that the area has attained the relevant NAAQS due
to emission reductions from existing controls. Thus, an area for which
a redesignation request has been submitted would have already attained
the NAAQS as a result of satisfying statutory requirements that came
due prior to the submission of the request. Absent a showing that
unadopted and unimplemented requirements are necessary for future
maintenance, it is reasonable to view the requirements applicable for
purposes of evaluating the redesignation request as including only
those SIP requirements that have already come due. These are the
requirements that led to attainment of the NAAQS. To require, for
redesignation approval, that a state also satisfy additional SIP
requirements coming due after the state submits its complete
redesignation request, and while EPA is reviewing it, would compel the
state to do more than is necessary to attain the NAAQS, without a
showing that the additional requirements are necessary for maintenance.
    In the context of this redesignation, the timing and nature of the
Court's January 4, 2013 decision in NRDC v. EPA compound the
consequences of imposing requirements that come due after the
redesignation request is submitted. The State submitted its
redesignation request on June 22, 2012, but the Court did not issue its
decision remanding EPA's 1997 PM2.5 implementation rule
concerning the applicability of the provisions of subpart 4 until
January 2013.
    To require the State's fully-completed and pending redesignation
request for the 2006 PM2.5 standard to comply now with
requirements of subpart 4 that the Court announced only in its January,
2013 decision on the 1997 PM2.5 implementation rule, would
be to give retroactive effect to such requirements when the State had
no notice that it was required to meet them. The D.C. Circuit
recognized the inequity of this type of retroactive impact in Sierra
Club v. Whitman, 285 F.3d 63 (D.C. Cir. 2002),\2\ where it upheld the
District Court's ruling refusing to make retroactive EPA's
determination that the St. Louis area did not meet its attainment
deadline. In that case, petitioners urged the Court to make EPA's
nonattainment determination effective as of the date that the statute
required, rather than the later date on which EPA actually made the
determination. The Court rejected this view, stating that applying it
``would likely impose large costs on States, which would face fines and
suits for not implementing air pollution prevention plans . . . even
though they were not on notice at the time.'' Id. at 68. Similarly, it
would be unreasonable to penalize the State of Connecticut by rejecting
its redesignation request for an area that is already attaining the
1997 and 2006 PM2.5 standards and that met all applicable
requirements known to be in effect at the time of the request. For EPA
now to reject the redesignation request solely because the state did
not expressly address subpart 4 requirements of which it had no notice,
would inflict the same unfairness condemned by the Court in Sierra Club
v. Whitman.
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    \2\ Sierra Club v. Whitman was discussed and distinguished in a
recent D.C. Circuit decision that addressed retroactivity in a quite
different context, where, unlike the situation here, EPA sought to
give its regulations retroactive effect. National Petrochemical and
Refiners Ass'n v. EPA. 630 F.3d 145, 163 (D.C. Cir. 2010), rehearing
denied 643 F.3d 958 (D.C. Cir. 2011), cert denied 132 S. Ct. 571
(2011).
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b. Subpart 4 Requirements and Connecticut's Redesignation Request
    Even if EPA were to take the view that the Court's January 4, 2013
decision requires that, in the context of a pending redesignation for
the 1997 and 2006 PM2.5 standards, subpart 4 requirements
were due and in effect at the time the State submitted its
redesignation request, EPA proposes to determine that the Southwestern
CT Area still qualifies for redesignation to attainment. As explained
below, EPA believes that the redesignation request for the Southwestern
CT Area, though not expressed in terms of subpart 4 requirements,
substantively meets the requirements of that subpart for purposes of
redesignating the area to attainment.
    With respect to evaluating the relevant substantive requirements of
subpart 4 for purposes of redesignating the Southwestern CT Area, EPA
notes that subpart 4 incorporates components of subpart 1 of part D,
which contains general air quality planning requirements for areas
designated as nonattainment. See Section 172(c). Subpart 4 itself
contains specific planning and scheduling requirements for
PM10 \3\ nonattainment areas, and under the Court's January
4, 2013 decision in NRDC v. EPA, these same statutory requirements also
apply for PM2.5 nonattainment areas. EPA has longstanding
general guidance that interprets the 1990 amendments to the CAA, making
recommendations to states for meeting the statutory requirements for
SIPs for nonattainment areas. See ``State Implementation Plans; General
Preamble for the Implementation of Title I of the Clear Air Act
Amendments of 1990,'' 57 FR 13498 (April 16, 1992) (the ``General
Preamble''). In the General Preamble, EPA discussed the relationship of
subpart 1 and subpart 4 SIP requirements, and pointed out that subpart
1 requirements were to an extent ``subsumed by, or integrally related
to, the more specific PM-10 requirements.'' 57 FR 13538 (April 16,
1992). The subpart 1 requirements include, among other things,
provisions for attainment demonstrations, reasonably available control
measures (RACM), reasonable further progress

(RFP), emissions inventories, and contingency measures.
---------------------------------------------------------------------------

    \3\ PM10 refers to particulates nominally 10
micrometers in diameter or smaller.
---------------------------------------------------------------------------

    For the purposes of this redesignation, in order to identify any
additional requirements which would apply under subpart 4, we are
considering the Southwestern CT Area to be a ``moderate''
PM2.5 nonattainment area. Under section 188 of the CAA, all
areas designated nonattainment areas under subpart 4 would initially be
classified by operation of law as ``moderate'' nonattainment areas, and
would remain moderate nonattainment areas unless and until EPA
reclassifies the area as a ``serious'' nonattainment area. Accordingly,
EPA believes that it is appropriate to limit the evaluation of the
potential impact of subpart 4 requirements to those that would be
applicable to moderate nonattainment areas. Sections 189(a) and (c) of
subpart 4 apply to moderate nonattainment areas and include the
following: (1) An approved permit program for construction of new and
modified major stationary sources (section 189(a)(1)(A)); (2) an
attainment demonstration (section 189(a)(1)(B)); (3) provisions for
RACM (section 189(a)(1)(C)); and (4) quantitative milestones
demonstrating RFP toward attainment by the applicable attainment date
(section 189(c)).
    The permit requirements of subpart 4, as contained in section
189(a)(1)(A), refer to and apply the subpart 1 permit provisions
requirements of sections 172 and 173 to PM10, without adding
to them. Consequently, EPA believes that section 189(a)(1)(A) does not
itself impose for redesignation purposes any additional requirements
for moderate areas beyond those contained in subpart 1.\4\ In any
event, in the context of redesignation, EPA has long relied on the
interpretation that a fully approved nonattainment new source review
program is not considered an applicable requirement for redesignation,
provided the area can maintain the standard with a prevention of
significant deterioration (PSD) program after redesignation. A detailed
rationale for this view is described in a memorandum from Mary Nichols,
Assistant Administrator for Air and Radiation, dated October 14, 1994,
entitled, ``Part D New Source Review Requirements for Areas Requesting
Redesignation to Attainment.'' See also rulemakings for Detroit,
Michigan (60 FR 12467-12468, March 7, 1995); Cleveland-Akron-Lorain,
Ohio (61 FR 20458, 20469-20470, May 7, 1996); Louisville, Kentucky (66
FR 53665, October 23, 2001); and Grand Rapids, Michigan (61 FR 31834-
31837, June 21, 1996).
---------------------------------------------------------------------------

    \4\ The potential effect of section 189(e) on section
189(a)(1)(A) for purposes of evaluating this redesignation is
discussed below.
---------------------------------------------------------------------------

    With respect to the specific attainment planning requirements under
subpart 4,\5\ when EPA evaluates a redesignation request under either
subpart 1 and/or 4, any area that is attaining the PM2.5
standard is viewed as having satisfied the attainment planning
requirements for these subparts. For redesignations, EPA has for many
years interpreted attainment-linked requirements as not applicable for
areas attaining the standard. In the General Preamble, EPA stated that:
---------------------------------------------------------------------------

    \5\ I.e., attainment demonstration, RFP, RACM, milestone
requirements, and contingency measures.

    The requirements for RFP will not apply in evaluating a request
for redesignation to attainment since, at a minimum, the air quality
data for the area must show that the area has already attained.
Showing that the State will make RFP towards attainment will,
---------------------------------------------------------------------------
therefore, have no meaning at that point.

    ``General Preamble for the Interpretation of Title I of the Clean
Air Act Amendments of 1990''; (57 FR 13498, 13564, April 16, 1992).
    The General Preamble also explained that

[t]he section 172(c)(9) requirements are directed at ensuring RFP
and attainment by the applicable date. These requirements no longer
apply when an area has attained the standard and is eligible for
redesignation. Furthermore, section 175A for maintenance plans * * *
provides specific requirements for contingency measures that
effectively supersede the requirements of section 172(c)(9) for
these areas.

Id.

    EPA similarly stated in its 1992 Calcagni memorandum that, ``The
requirements for reasonable further progress and other measures needed
for attainment will not apply for redesignations because they only have
meaning for areas not attaining the standard.''
    It is evident that even if we were to consider the Court's January
4, 2013 decision in NRDC v. EPA to mean that attainment-related
requirements specific to subpart 4 should be imposed retroactively \6\
and, thus, are now past due, those requirements do not apply to an area
that is attaining the 1997 and 2006 PM2.5 standards, for the
purpose of evaluating a pending request to redesignate the area to
attainment. EPA has consistently enunciated this interpretation of
applicable requirements under section 107(d)(3)(E) since the General
Preamble was published more than twenty years ago. Courts have
recognized the scope of EPA's authority to interpret ``applicable
requirements'' in the redesignation context. See Sierra Club v. EPA,
375 F.3d 537 (7th Cir. 2004).
---------------------------------------------------------------------------

    \6\ As EPA has explained above, we do not believe that the
Court's January 4, 2013 decision should be interpreted so as to
impose these requirements on the states retroactively. Sierra Club
v. Whitman, supra.
---------------------------------------------------------------------------

    Moreover, even outside the context of redesignations, EPA has
viewed the obligations to submit attainment-related SIP planning
requirements of subpart 4 as inapplicable for areas that EPA determines
are attaining the standard. EPA's prior ``Clean Data Policy''
rulemakings for the PM10 NAAQS, also governed by the
requirements of subpart 4, explain EPA's reasoning. They describe the
effects of a determination of attainment on the attainment-related SIP
planning requirements of subpart 4. See ``Determination of Attainment
for Coso Junction Nonattainment Area,'' (75 FR 27944, May 19, 2010).
See also Coso Junction proposed PM10 redesignation, (75 FR
36023, 36027, June 24, 2010); Proposed and Final Determinations of
Attainment for San Joaquin Nonattainment Area (71 FR 40952, 40954-55,
July 19, 2006; and 71 FR 63641, 63643-47 October 30, 2006). In short,
EPA in this context has also long concluded that to require states to
meet superfluous SIP planning requirements is not necessary and not
required by the CAA, so long as those areas continue to attain the
relevant NAAQS.
    Elsewhere in this notice, EPA proposes to determine that the
Southwestern CT Area has attained the 1997 and 2006 PM2.5
standards. Under its longstanding interpretation, EPA is proposing to
determine here that the area meets the attainment-related plan
requirements of subparts 1 and 4.
    Thus, EPA is proposing to conclude that the requirements to submit
an attainment demonstration under 189(a)(1)(B), a RACM determination
under section 172(c)(1) and section 189(a)(1)(c), a RFP demonstration
under 189(c)(1), and contingency measure requirements under section
172(c)(9) are satisfied for purposes of evaluating the redesignation
request.
c. Subpart 4 and Control of PM2.5 Precursors
    The D.C. Circuit in NRDC v. EPA remanded to EPA the two rules at
issue in the case with instructions to EPA to re-promulgate them
consistent with the requirements of subpart 4. EPA in this section
addresses the Court's opinion with respect to PM2.5
precursors. While past implementation of subpart 4 for PM10
has allowed for control of PM10 precursors such as
NOX from major stationary, mobile, and area sources in order
to attain the standard as

expeditiously as practicable, CAA section 189(e) specifically provides
that control requirements for major stationary sources of direct
PM10 shall also apply to PM10 precursors from
those sources, except where EPA determines that major stationary
sources of such precursors ``do not contribute significantly to
PM10 levels which exceed the standard in the area.''
    EPA's 1997 PM2.5 implementation rule, remanded by the
D.C. Circuit, contained rebuttable presumptions concerning certain
PM2.5 precursors applicable to attainment plans and control
measures related to those plans. Specifically, in 40 CFR 51.1002, EPA
provided, among other things, that a state was ``not required to
address VOC [and ammonia] as . . . PM2.5 attainment plan
precursor[s] and to evaluate sources of VOC [and ammonia] emissions in
the State for control measures.'' EPA intended these to be rebuttable
presumptions. EPA established these presumptions at the time because of
uncertainties regarding the emission inventories for these pollutants
and the effectiveness of specific control measures in various regions
of the country in reducing PM2.5 concentrations. EPA also
left open the possibility for such regulation of VOC and ammonia in
specific areas where that was necessary.
    The Court in its January 4, 2013 decision made reference to both
section 189(e) and 40 CFR 51.1002, and stated that, ``In light of our
disposition, we need not address the petitioners' challenge to the
presumptions in [40 CFR 51.1002] that volatile organic compounds and
ammonia are not PM2.5 precursors, as subpart 4 expressly
governs precursor presumptions.'' NRDC v. EPA, at 27, n.10.
    Elsewhere in the Court's opinion, however, the Court observed:

    Ammonia is a precursor to fine particulate matter, making it a
precursor to both PM2.5 and PM10. For a
PM10 nonattainment area governed by subpart 4, a
precursor is presumptively regulated. See 42 U.S.C. Sec.  7513a(e)
[section 189(e)].

    Id. at 21, n.7. For a number of reasons, EPA believes that its
proposed redesignation of the Southwestern CT Area is consistent with
the Court's decision on this aspect of subpart 4. First, while the
Court, citing section 189(e), stated that ``for a PM10 area
governed by subpart 4, a precursor is `presumptively regulated,' '' the
Court expressly declined to decide the specific challenge to EPA's 1997
PM2.5 implementation rule provisions regarding ammonia and
VOC as precursors. The Court had no occasion to reach whether and how
it was substantively necessary to regulate any specific precursor in a
particular PM2.5 nonattainment area, and did not address
what might be necessary for purposes of acting upon a redesignation
request.
    However, even if EPA takes the view that the requirements of
subpart 4 were deemed applicable at the time the state submitted the
redesignation request, and disregards the implementation rule's
rebuttable presumptions regarding ammonia and VOC as PM2.5
precursors (and any similar provisions reflected in the guidance for
the 2006 PM2.5 standard), the regulatory consequence would
be to consider the need for regulation of all precursors from any
sources in the area to demonstrate attainment and to apply the section
189(e) provisions to major stationary sources of precursors. In the
case of the Southwestern CT Area, EPA believes that doing so is
consistent with proposing redesignation of the area for the 1997 and
2006 PM2.5 standards. The Southwestern CT Area has attained
the standard without any specific additional controls of VOC and
ammonia emissions from any sources in the area.
    Precursors in subpart 4 are specifically regulated under the
provisions of section 189(e), which requires, with important
exceptions, control requirements for major stationary sources of
PM10 precursors.\7\ Under subpart 1 and EPA's prior
implementation rule, all major stationary sources of PM2.5
precursors were subject to regulation, with the exception of ammonia
and VOC. Thus, we must address here whether additional controls of
ammonia and VOC from major stationary sources are required under
section 189(e) of subpart 4 in order to redesignate the area for the
1997 PM2.5 standard. As explained below, we do not believe
that any additional controls of ammonia and VOC are required in the
context of this redesignation.
---------------------------------------------------------------------------

    \7\ Under either subpart 1 or subpart 4, for purposes of
demonstrating attainment as expeditiously as practicable, a state is
required to evaluate all economically and technologically feasible
control measures for direct PM emissions and precursor emissions,
and adopt those measures that are deemed reasonably available.
---------------------------------------------------------------------------

    In the General Preamble, EPA discusses its approach to implementing
section 189(e). See 57 FR 13538-13542. With regard to precursor
regulation under section 189(e), the General Preamble explicitly stated
that control of VOCs under other Act requirements may suffice to
relieve a state from the need to adopt precursor controls under section
189(e). 57 FR 13542. In this proposal, EPA proposes to determine that
the SIP has met the provisions of section 189(e) with respect to
ammonia and VOCs as precursors. This proposed determination is based on
our findings that (1) the Southwestern CT Area contains no major
stationary sources of ammonia, and (2) existing major stationary
sources of VOC are adequately controlled under other provisions of the
CAA regulating the ozone NAAQS.\8\ In the alternative, EPA proposes to
determine that, under the express exception provisions of section
189(e), and in the context of the redesignation of the area, which is
attaining the 1997 and 2006 PM2.5 standards, at present
ammonia and VOC precursors from major stationary sources do not
contribute significantly to levels exceeding the 1997 and 2006
PM2.5 standards in the Southwestern CT Area.
---------------------------------------------------------------------------

    \8\ The Southwestern CT area has reduced VOC emissions through
the implementation of various control programs including VOC
Reasonably Available Control Technology regulations and various on-
road and non-road motor vehicle control programs.
---------------------------------------------------------------------------

    EPA notes that its 1997 PM2.5 implementation rule
provisions in 40 CFR 51.1002 were not directed at evaluation of
PM2.5 precursors in the context of redesignation, but at SIP
plans and control measures required to bring a nonattainment area into
attainment of the 1997 PM2.5 NAAQS. By contrast,
redesignation to attainment primarily requires the area to have already
attained due to permanent and enforceable emission reductions, and to
demonstrate that controls in place can continue to maintain the
standard. Thus, even if we regard the Court's January 4, 2013 decision
as calling for ``presumptive regulation'' of ammonia and VOC for
PM2.5 under the attainment planning provisions of subpart 4,
those provisions in and of themselves do not require additional
controls of these precursors for an area that already qualifies for
redesignation. Nor does EPA believe that requiring Connecticut to
address precursors differently than they have already would result in a
substantively different outcome.
    Although, as EPA has emphasized, its consideration here of
precursor requirements under subpart 4 is in the context of a
redesignation to attainment, EPA's existing interpretation of subpart 4
requirements with respect to precursors in attainment plans for
PM10 contemplates that states may develop attainment plans
that regulate only those precursors that are necessary for purposes of
attainment in the area in question, i.e., states may determine that
only certain precursors need be regulated for attainment and control

purposes.\9\ Courts have upheld this approach to the requirements of
subpart 4 for PM10.\10\ EPA believes that application of
this approach to PM2.5 precursors under subpart 4 is
reasonable. Because the Southwestern CT Area has already attained the
1997 and 2006 PM2.5 NAAQS with its current approach to
regulation of PM2.5 precursors, EPA believes that it is
reasonable to conclude in the context of this redesignation that there
is no need to revisit the attainment control strategy with respect to
the treatment of precursors. Even if the Court's decision is construed
to impose an obligation, in evaluating this redesignation request, to
consider additional precursors under subpart 4, it would not affect
EPA's approval here of Connecticut's request for redesignation of the
Southwestern CT Area. In the context of a redesignation, the area has
shown that it has attained the standard. Moreover, the state has shown
and EPA is proposing to determine that attainment in this area is due
to permanent and enforceable emissions reductions on all precursors
necessary to provide for continued attainment. It follows logically
that no further control of additional precursors is necessary.
Accordingly, EPA does not view the January 4, 2013 decision of the
Court as precluding redesignation of the Southwestern CT Area to
attainment for the 1997 annual and 2006 24-hour PM2.5 NAAQS
at this time.
---------------------------------------------------------------------------

    \9\ See, e.g., ``Approval and Promulgation of Implementation
Plans for California--San Joaquin Valley PM-10 Nonattainment Area;
Serious Area Plan for Nonattainment of the 24-Hour and Annual PM-10
Standards,'' 69 FR 30006 (May 26, 2004) (approving a PM10
attainment plan that impose controls on direct PM10 and
NOX emissions and did not impose controls on
SO2, VOC, or ammonia emissions).
    \10\ See, e.g., Assoc. of Irritated Residents v. EPA et al., 423
F.3d 989 (9th Cir. 2005).
---------------------------------------------------------------------------

    In sum, even if Connecticut were required to address precursors for
the Southwestern CT Area under subpart 4 rather than under subpart 1,
as interpreted in EPA's remanded PM2.5 implementation rule,
EPA would still conclude that the area had met all applicable
requirements for purposes of redesignation in accordance with section
107(d)(3)(E)(ii) and (v).
d. Maintenance Plan and Evaluation of Precursors
    With regard to the redesignation of Southwestern CT Area, in
evaluating the effect of the Court's remand of EPA's implementation
rule, which included presumptions against consideration of VOC and
ammonia as PM2.5 precursors, EPA in this proposal is also
considering the impact of the decision on the maintenance plan required
under sections 175A and 107(d)(3)(E)(iv). To begin with, EPA notes that
the area has attained the 1997 annual and 2006 24-hour PM2.5
standards and that the state has shown that attainment of those
standards is due to permanent and enforceable emission reductions.
    EPA proposes to determine that the State's maintenance plan shows
continued maintenance of the standards by tracking the levels of the
precursors whose control brought about attainment of the 1997 and 2006
PM2.5 standards in the Southwestern CT Area. EPA, therefore,
believes that the only additional consideration related to the
maintenance plan requirements that results from the Court's January 4,
2013 decision is that of assessing the potential role of VOC and
ammonia in demonstrating continued maintenance in this area. As
explained below, based upon documentation provided by the State and
supporting information, EPA believes that the maintenance plan for the
Southwestern CT Area need not include any additional emission
reductions of VOC or ammonia in order to provide for continued
maintenance of the 1997 and 2006 PM2.5 standards.

III. What are the criteria for redesignation to attainment?

    The CAA sets forth the requirements for redesignating a
nonattainment area to attainment. Specifically, section 107(d)(3)(E) of
the CAA allows for redesignation provided that: (1) EPA determines that
the area has attained the applicable NAAQS; (2) EPA has fully approved
the applicable state implementation plan for the area under CAA section
110(k); (3) air-quality improvements are due to permanent and
enforceable emission reductions; and (4) EPA has fully approved a
maintenance plan for the area meeting the requirements of CAA section
175A; and (5) the state containing such area has met all requirements
applicable to the area under CAA section 110 and part D.
    EPA has provided guidance on redesignation in the General Preamble
for the Implementation of Title I of the CAA Amendments of 1990 (April
16, 1992, 57 FR 13498) (supplemented on April 28, 1992, 57 FR 18070)
and has provided further guidance on processing redesignation requests
in the following documents:

    1. ``Procedures for Processing Requests to Redesignate Areas to
Attainment,'' Memorandum from John Calcagni, Director, Air Quality
Management Division, September 4, 1992 (hereafter referred to as the
``Calcagni Memorandum'');
    2. ``State Implementation Plan (SIP) Actions Submitted in
Response to Clean Air Act (CAA) Deadlines,'' Memorandum from John
Calcagni, Director, Air Quality Management Division, October 28,
1992; and
    3. ``Part D New Source Review (Part D NSR) Requirements for
Areas Requesting Redesignation to Attainment,'' Memorandum from Mary
D. Nichols, Assistant Administrator for Air and Radiation, October
14, 1994.

IV. What is EPA's analysis of the State's request?

    EPA is proposing to determine that the Southwestern CT Area has met
all applicable redesignation criteria under CAA section 107(d)(3)(E).
The basis for EPA's proposed approval of the redesignation request is
discussed below.

A. Has the Southwestern CT Area attained the 1997 PM2.5
NAAQS?

    On November 15, 2010 (75 FR 69589), EPA determined that the New
York Metropolitan Area, which includes the Southwestern CT Area,
attained the 1997 annual PM2.5 NAAQS. EPA determines that an
area has attained the 1997 annual PM2.5 NAAQS based on three
complete, consecutive calendar years of quality-assured air quality
data. To attain the annual standard, the three-year average of the
annual mean PM2.5 concentrations for designated monitoring
sites in an area must not exceed 15.0 [mu]g/m\3\. The data must be
collected and quality-assured in accordance with 40 CFR part 58, and
recorded in EPA's Air Quality System (AQS). The monitors generally
should have remained at the same location for the duration of the
monitoring period required for demonstrating attainment.
    Specifically, on November 15, 2010 (75 FR 69589), EPA determined
that the New York Metropolitan Area attained the 1997 annual
PM2.5 NAAQS based on complete, quality-assured monitoring
data for 2007-2009, and that it had attained this standard as of April
5, 2010, its applicable attainment date. Further discussion of
pertinent air quality issues underlying this determination was provided
in the notice of proposed rulemaking for EPA's determination of
attainment for this Area, published on August 2, 2010 (75 FR 45076).
    In addition, as discussed below with respect to the maintenance
plan, the CT DEEP has committed to continue to operate an EPA-approved
monitoring network in the area as necessary to demonstrate maintenance
of the NAAQS. Connecticut remains obligated to continue to ensure the
quality of monitoring data in accordance with 40 CFR part 58, and to
enter all data into the AQS in accordance with Federal

guidelines. In summary, the area has attained the 1997 annual
PM2.5 NAAQS.

B. Has the Southwestern CT Area attained the 2006 PM2.5
NAAQS?

    On December 31, 2012 (77 FR 76867), EPA determined that the New
York Metropolitan Area, which includes the Southwestern CT Area,
attained the 2006 24-hour PM2.5 NAAQS. EPA determines that
an area has attained the 2006 24-hour PM2.5 NAAQS based on
three complete, consecutive calendar years of quality-assured air
quality data. The 24-hour standard is met when the 98th percentile 24-
hour concentration, as determined in accordance with 40 CFR part 50,
Appendix N, is less than or equal to 35.0 [micro]g/m\3\. The data must
be collected and quality-assured in accordance with 40 CFR part 58, and
recorded in EPA's AQS. The monitors generally should have remained at
the same location for the duration of the monitoring period required
for demonstrating attainment.
    Specifically, on December 31, 2012 (77 FR 76867), EPA determined
that the New York Metropolitan Area attained the 2006 24-hour
PM2.5 NAAQS based on complete, quality-assured monitoring
data for 2007-2009, 2008-2010, and 2009-2011, and that it had attained
this standard ahead of December 14, 2014, its applicable attainment
date. Further discussion of pertinent air quality issues underlying
this determination was provided in the notice of proposed rulemaking
for EPA's determination of attainment for this Area, published on
August 30, 2012 (77 FR 52626).
    In addition, as discussed below with respect to the maintenance
plan, the CT DEEP has committed to continue to operate an EPA-approved
monitoring network in the area as necessary to demonstrate maintenance
of the NAAQS. Connecticut remains obligated to continue to ensure the
quality of monitoring data in accordance with 40 CFR part 58, and to
enter all data into the AQS in accordance with Federal guidelines. In
summary, the area has attained the 2006 24-hour PM2.5 NAAQS.

C. Has the State of Connecticut met all applicable requirements of
Section 110 and Part D and does the Southwestern CT Area have a fully
approved SIP under Section 110(k) of the CAA for purposes of
redesignation to attainment?

    EPA is proposing to determine that the Southwestern CT Area has met
all SIP requirements applicable for purposes of this redesignation
under section 110 of the CAA (General SIP Requirements) and that, upon
final approval of the 2007 base-year emissions inventory, as discussed
below in this proposed rulemaking, it will have met all applicable SIP
requirements under part D of Title I of the CAA, in accordance with CAA
section 107(d)(3)(E)(v). In addition, EPA is proposing to find that all
applicable requirements of the Connecticut SIP for purposes of
redesignation have been approved in accordance with CAA section
107(d)(3)(E)(ii). In making these proposed determinations, EPA
ascertained which SIP requirements are applicable for purposes of
redesignation of this Area, and concluded that the applicable portions
of the SIP meeting these requirements are fully approved under section
110(k) of the CAA.
1. Section 110 and General SIP Requirements
    Section 110(a)(2) of Title I of the CAA delineates the general
requirements for a SIP, which include enforceable emissions limitations
and other control measures, means, or techniques, provisions for the
establishment and operation of appropriate devices necessary to collect
data on ambient air quality, and programs to enforce the limitations.
The general SIP elements and requirements set forth in CAA section
110(a)(2) include, but are not limited to the following:
     Submittal of a SIP that has been adopted by the state
after reasonable public notice and hearing;
     Provisions for establishment and operation of appropriate
procedures needed to monitor ambient air quality;
     Implementation of a source permit program; provisions for
the implementation of Part C requirements (Prevention of Significant
Deterioration (PSD));
     Provisions for the implementation of Part D requirements
for New Source Review (NSR) permit programs;
     Provisions for air pollution modeling; and
     Provisions for public and local agency participation in
planning and emission control rule development.
    Section 110(a)(2)(D) of the CAA requires that SIPs contain certain
measures to prevent sources in a state from significantly contributing
to air quality problems in another state. To implement this provision,
EPA has required certain states to establish programs to address the
interstate transport of air pollutants in accordance with the
NOX SIP Call, October 27, 1998 (63 FR 57356), amendments to
the NOX SIP Call, May 14, 1999 (64 FR 26298) and March 2,
2000 (65 FR 11222), and CAIR, May 12, 2005 (70 FR 25162). However, the
CAA section 110(a)(2)(D) requirements for a state are not linked with a
particular nonattainment area's designation and classification in that
state. EPA believes that the requirements linked with a particular
nonattainment area's designation and classifications are the relevant
measures to evaluate in reviewing a redesignation request. The
transport SIP submittal requirements, where applicable, continue to
apply to a state regardless of the designation of any one particular
area in the state. Thus, EPA does not believe that these requirements
are applicable requirements for purposes of redesignation.
    Further, we conclude the other section 110 elements described above
that are not connected with nonattainment plan submissions and not
linked with an area's attainment status are also not applicable
requirements for purposes of redesignation. A state remains subject to
these requirements after an area is redesignated to attainment. We
conclude that only the section 110 and part D requirements that are
linked with a particular area's designation are the relevant measures
which we may consider in evaluating a redesignation request. This
approach is consistent with EPA's existing policy on applicability of
conformity and oxygenated fuels requirements for redesignation
purposes, as well as with section 184 ozone transport requirements. See
Reading, Pennsylvania, proposed and final rulemakings (61 FR 53174,
October 10, 1996), (62 FR 24826, May 7, 1997); Cleveland-Akron-Lorain,
Ohio final rulemaking (61 FR 20458, May 7, 1996); and Tampa, Florida
final rulemaking (60 FR 62748, December 7, 1995). See also the
discussion on this issue in the Cincinnati, Ohio redesignation (65 FR
at 37890, June 19, 2000) and in the Pittsburgh, Pennsylvania
redesignation (66 FR at 53099, October 19, 2001).
    We have reviewed Connecticut's SIP and have concluded that it meets
the general SIP requirements under section 110 of the CAA, to the
extent they are applicable for purposes of redesignation. EPA has
previously approved provisions of the Connecticut SIP addressing
section 110 requirements (including provisions addressing particulate
matter). On September 4, 2008 and September 18, 2009, Connecticut made
submittals for the 1997 annual and 2006 24-hour PM2.5
standards, respectively, addressing ``infrastructure SIP'' elements
required by section 110(a)(2) of the CAA. EPA approved or conditionally
approved all elements of Connecticut's submittals on October 16, 2012,
at 77 FR 63228. The

requirements of section 110(a)(2), however, are statewide requirements
that are not linked to the PM2.5 nonattainment status of the
Southwestern CT Area. Therefore, EPA believes that these SIP elements
are not applicable requirements for purposes of review of the State's
PM2.5 redesignation request.
    EPA also has previously approved PM2.5 and
PM2.5 precursor control measures that are permanent and
enforceable controls that will remain in place following redesignation
(see Table 1).

    Table 1--List of Connecticut Control Measures for PM2.5 and PM2.5
                               Precursors
------------------------------------------------------------------------
    Name of control measure      Type of measure     Approval citation
------------------------------------------------------------------------
Tier 2 Vehicle Standards and    federal rule.....  Promulgated at 40 CFR
 Gasoline Sulfur Standards.                         part 86.
Heavy-Duty Diesel and Gasoline  federal rule.....  Promulgated at 40 CFR
 Highway Vehicle Standards.                         part 86.
Motorcycle Exhaust Standards..  federal rule.....  Promulgated at 40 CFR
                                                    part 86.
Large Non-road Diesel Engine    federal rule.....  Promulgated at 40 CFR
 Standards.                                         part 89.
Non-road Spark-Ignition         federal rule.....  Promulgated at 40 CFR
 Engines and Recreational                           part 90.
 Engine Standards.
NOX SIP Call..................  federal rule.....  63 FR 57356 (10/27/
                                                    1998).
CAIR..........................  federal rule.....  70 FR 25162 (5/12/
                                                    2005).
Control of Sulfur Compound      SIP-approved       46 FR 56612 (11/18/
 Emissions 19-508-19.            state regulation.  1981).
Control of SO2 emissions from   SIP-approved       Approval signed 4/26/
 power plants and other large    state regulation.  2013, not yet
 stationary sources 22a-174-                        published. See CT
 19a.                                               Regional Haze SIP
                                                    docket (EPA-R01-OAR-
                                                    2009-0919).
Control of NOX Emissions 22a-   SIP-approved       62 FR 52016 (10/06/
 174-22.                         state regulation.  1997).
Post-2002 NOX Budget Program    SIP-approved       65 FR 81743 (12/27/
 22a-174-22b.                    state regulation.  2000); superseded by
                                                    CAIR (22a-174-22c).
CAIR NOX Ozone Season Trading   SIP-approved       73 FR 4105 (01/24/
 Program 22a-174-22c.            state regulation.  2008).
Control of Particulate          SIP-approved       47 FR 41958 (09/23/
 Emissions 19-508-18.            state regulation.  1982).
Emission Standards and On-      SIP-approved       73 FR 74019 (12/05/
 Board Diagnostic II Test        state regulation.  2008).
 Requirements for Periodic
 Motor Vehicle Inspection and
 Maintenance 22a-174-27.
Low Emission Vehicles 22a-174-  SIP-approved       64 FR 44411 (08/16/
 36b.                            state regulation.  1999).
Municipal Waste Combustors 22a- SIP-approved       66 FR 63311 (12/06/
 174-38.                         state regulation.  2001).
Permit to Construct and         SIP-approved       76 FR 26933 (05/10/
 Operate Stationary Sources      state regulation.  2011).
 22a-174-3a.
------------------------------------------------------------------------

2. Part D SIP Requirements
    EPA has determined that, upon approval of the base-year emissions
inventories discussed below, the Connecticut SIP will meet the
applicable SIP requirements for the Southwestern CT Area applicable for
purposes of redesignation under part D of the CAA. Subpart 1 of part D,
found in sections 172-176 of the CAA, sets forth the basic
nonattainment requirements applicable to all nonattainment areas.
Subpart 1 Section 172 Requirements
    On November 15, 2010 (75 FR 69589) and December 31, 2012 (77 FR
76867), EPA made determinations that the New York Metropolitan Area,
including the Southwestern CT Area, is attaining the 1997 annual and
2006 24-hour PM2.5 NAAQS, respectively. These determinations
of attainment were based on quality-assured and certified air-quality
data for the 2007-2009 monitoring period (1997 NAAQS) and for the 2007-
2009, 2008-2010, and 2009-2011 monitoring periods (2006 NAAQS) showing
that the Southwestern CT Area had attained the applicable NAAQS.
Monitoring data for 2012 are also consistent with continued attainment
of the standards. Under EPA's Clean Data Policy and pursuant to 40 CFR
51.1004(c), upon determination by EPA that an area designated
nonattainment of the PM2.5 NAAQS has attained the standard,
the requirement for such an area to submit an attainment demonstration
and associated reasonably achievable control technology (RACT)/RACM,
RFP, contingency measures, and other planning SIPs related to the
attainment of the PM2.5 NAAQS are suspended until EPA
determines that the area has again violated the PM2.5 NAAQS,
at which time such plans are required to be submitted.\11\ As a result
of the determinations of attainment for the Southwestern CT Area, the
only remaining requirement under CAA section 172 to be considered is
the emissions inventory required under CAA section 172(c)(3).
---------------------------------------------------------------------------

    \11\ Nevertheless, CT DEEP did submit a SIP on November 18,
2008, which included an attainment demonstration for the 1997 annual
PM2.5 standard for the Southwestern CT Area. In its June
22, 2012 redesignation request, CT DEEP states that it will withdraw
the attainment demonstration SIP, effective one day after EPA signs
the final rule approving Connecticut's redesignation request and
maintenance plans.
---------------------------------------------------------------------------

    In this rulemaking action, EPA is proposing to approve
Connecticut's 2007 base-year emissions inventory in accordance with
section 172(c)(3) of the CAA. Final approval of the 2007 base-year
emissions inventory will satisfy the emissions inventory requirement
under section 172(c)(3) of the CAA.
    The General Preamble for Implementation of Title I also discusses
the evaluation of these requirements in the context of EPA's
consideration of a redesignation request. The General Preamble sets
forth EPA's view of applicable requirements for purposes of evaluating
redesignation requests when an area is attaining the standard. See

General Preamble for Implementation of Title I (57 FR 13498, April 16,
1992).
    Because attainment of the 1997 annual and 2006 24-hour
PM2.5 standards has been reached for the Southwestern CT
Area, no additional measures are needed to provide for attainment, and
CAA section 172(c)(1) requirements for an attainment demonstration and
RACT/RACM are no longer considered to be applicable for purposes of
redesignation as long as the area continues to attain the standards
until redesignation. See 40 CFR 51.1004(c). The RFP requirement under
CAA section 172(c)(2) and contingency measures requirement under CAA
section 172(c)(9) are similarly not relevant for purposes of
redesignation.
    Section 172(c)(3) of the CAA requires submission and approval of a
comprehensive, accurate and current inventory of actual emissions. The
maintenance plan submitted by CT DEEP includes a 2007 base-year
emissions inventory that meets this requirement. The 2007 base-year
emissions inventory for the Southwestern CT Area, compiled jointly by
CT DEEP and the Mid-Atlantic Regional Air Management Association
(MARAMA), contains PM2.5 (including condensables), and
PM2.5 precursors, SO2 and NOX. MARAMA
emissions inventories also include the PM2.5 precursors
ammonia (NH3) and volatile organic compounds (VOC). See
Appendix C of Connecticut's June 22, 2012 redesignation request. The
emissions inventories cover the general source categories of EGU point
sources, non-EGU point sources (i.e., individual industrial,
commercial, and institutional facilities), area sources (i.e.,
aggregated small, non-permitted sources such as small industrial/
commercial facilities, residential heating furnaces, and road dust re-
entrainment), on-road mobile sources (i.e., cars, trucks, buses, and
other vehicles on public roadways), and nonroad mobile sources (e.g.,
marine vessels, airplanes, railroad locomotives, forklifts, lawn and
garden equipment, portable generators (non-road MAR). However, there is
one exception to the source category coverage mentioned above. MARAMA's
VOC and NH3 emission estimates did not include estimates for
the on-road mobile sector, and so the emission values in Table 4 below
represent values taken from EPA's regulatory impact analysis for the PM
NAAQS.
    A summary of the inventory development process is given below under
``EPA's analysis of the Southwestern CT Area maintenance plan.''
Connecticut provided detailed descriptions of the derivation of
emission estimates in Appendices A-I of their June 22, 2012 submittal.
    Tables 2 and 3 show the 2007 base-year emissions for
PM2.5 and PM2.5 precursors, SO2 and
NOX, which are the principal PM2.5 precursors in
the Southwestern CT Area. Table 4 shows the other PM2.5
precursors, ammonia and VOC, for the entire state of Connecticut. VOC
emission levels in Connecticut, including the Southwestern CT Area,
have historically been well-controlled under SIP requirements related
to ozone and other pollutants. Total ammonia emissions throughout the
state are very low, estimated for 2007 to be 5,765 tons per year. This
amount of statewide ammonia emissions is small compared to the total
amounts of SO2 and NOX, and even direct
PM2.5 emissions from sources within just the two-county
Southwestern CT Area. Moreover, available information shows that no
precursor, including VOC and ammonia, is expected to increase over the
maintenance period so as to interfere with or undermine the State's
maintenance demonstration, as further discussed below under ``EPA's
analysis of the Southwestern CT Area maintenance plan.'' The proposed
approval of the 2007 base-year emissions inventory in this rulemaking
action will, when finalized, meet the requirements of CAA section
172(c)(3).

      Table 2--New Haven County, CT: PM2.5, SO2 and NOX Emissions (tpy) for Base-Year 2007 by Source Sector
----------------------------------------------------------------------------------------------------------------
                             Sector                                     SO2             NOX            PM2.5
----------------------------------------------------------------------------------------------------------------
Point (EGU).....................................................           822.7           639.6            88.1
Point (Non-EGU).................................................            55.6           822.7            40.4
Area............................................................         3,707.7         2,936.1         1,900.3
Marine Vessels, Airplanes, RR Locomotives (MAR).................           727.4         3,945.9           168.5
Nonroad (NMIM)..................................................           174.1         3,688.1           279.1
Onroad (MOVES)..................................................            91.8        11,502.7           389.6
                                                                 -----------------------------------------------
    Total.......................................................         5,579.2        23,535.1         2,866.0
----------------------------------------------------------------------------------------------------------------
Note: Primary PM2.5 includes filterables and condensables.

      Table 3--Fairfield County, CT: PM2.5, SO2 and NOX Emissions (tpy) for Base-Year 2007 by Source Sector
----------------------------------------------------------------------------------------------------------------
                             Sector                                     SO2             NOX            PM2.5
----------------------------------------------------------------------------------------------------------------
Point (EGU).....................................................         3,311.2         2,268.5           283.5
Point (Non-EGU).................................................           154.8         1,875.4            44.7
Area............................................................         3,917.3         3,088.8         1,991.5
Marine Vessels, Airplanes, RR Locomotives (MAR).................           353.4         3,034.2           119.9
Nonroad (NMIM)..................................................           215.8         4,648.1           403.0
Onroad (MOVES)..................................................            84.3        11,888.9           404.4
                                                                 -----------------------------------------------
    Total.......................................................         8,036.7        26,804.0         3,247.0
----------------------------------------------------------------------------------------------------------------

Table 4--Connecticut: Ammonia and VOC Emissions (tpy) for Base-Year 2007
                            by Source Sector.
------------------------------------------------------------------------
                                                                Ammonia
                      Sector                           VOC       (NH3)
------------------------------------------------------------------------
Point (EGU).......................................        143          0
Point (nonEGU)....................................      1,447          0
Area..............................................     57,253      4,421
Non-road mobile...................................     20,721         16
Commercial Marine Vessels.........................        161          3
Airports..........................................        509          0
Railroad Locomotives..............................         73          1
On-road mobile....................................     28,967      1,324
                                                   ---------------------
    Total.........................................    109,274      5,765
------------------------------------------------------------------------

    Section 172(c)(4) of the CAA requires the identification and
quantification of allowable emissions for major new and modified
stationary sources in an area, and CAA section 172(c)(5) requires new
source permits for the construction and operation of new and modified
major stationary sources anywhere in the nonattainment area. EPA has
determined that, since the PSD requirements will apply after
redesignation, areas being redesignated need not comply with the
requirement that a nonattainment NSR program be approved prior to
redesignation, provided that the area demonstrates maintenance of the
NAAQS without part D NSR. A more detailed rationale for this view is
described in a memorandum from Mary Nichols, Assistant Administrator
for Air and Radiation, dated October 14, 1994 entitled, ``Part D New
Source Review Requirements for Areas Requesting Redesignation to
Attainment.'' Nevertheless, Connecticut currently has an approved NSR
program, established in RCSA section 22a-174-2a with amendments in 22a-
174-3a. See 68 FR 9009 (February 27, 2003) and 76 FR 26933 (May 10,
2011). However, Connecticut's PSD program for the 1997 annual and 2006
24-hour PM2.5 NAAQS will become effective in Southwestern CT
Area (i.e., New Haven and Fairfield Counties) upon redesignation to
attainment.
    Section 172(c)(6) of the CAA requires the SIP to contain control
measures necessary to provide for attainment of the NAAQS. Because
attainment has been reached for the Southwestern CT Area, no additional
measures are needed to provide for attainment.
    Section 172(c)(7) of the CAA requires the SIP to meet the
applicable provisions of CAA section 110(a)(2). As noted previously, we
believe the Connecticut SIP meets the requirements of CAA section
110(a)(2) that are applicable for purposes of redesignation.
Subpart 1, Section 176 Conformity Requirements
    Section 176(c) of the CAA requires states to establish criteria and
procedures to ensure that federally-supported or funded activities,
including highway projects, conform to the air quality planning goals
in the applicable SIPs. The requirement to determine conformity applies
to transportation plans, programs, and projects developed, funded or
approved under title 23 of the U.S. Code and the Federal Transit Act
(transportation conformity) as well as to all other federally-supported
or funded projects (general conformity). State conformity revisions
must be consistent with federal conformity regulations relating to
consultation, enforcement and enforceability, which EPA promulgated
pursuant to CAA requirements.
    EPA interprets the conformity SIP requirements as not applying for
purposes of evaluating the redesignation request under section 107(d)
for two reasons. First, the requirement to submit SIP revisions to
comply with the conformity provisions of the CAA continues to apply to
areas after redesignation to attainment, since such areas would be
subject to a section 175A maintenance plan. Second, EPA's federal
conformity rules require the performance of conformity analyses in the
absence of federally-approved state rules. Therefore, because areas are
subject to the conformity requirements regardless of whether they are
redesignated to attainment and, because they must implement conformity
under federal rules if state rules are not yet approved, it is
reasonable to view these requirements as not applying for purposes of
evaluating a redesignation request. See Wall v. EPA, 265 F.3d 426 (6th
Cir. 2001), upholding this interpretation. See also 60 FR 62748, 62749-
62750 (December 7, 1995) (Tampa, Florida).
    Connecticut's June 22, 2012 redesignation request included new fine
particle motor vehicle emissions budgets (MVEBs) as part of their
maintenance plan. The SIP establishes annual direct PM2.5
and annual NOX transportation conformity budgets for 2017
and 2025 to ensure that future emissions from on-road mobile sources
provide for continuing attainment of the 1997 annual and 2006 24-hour
PM2.5 NAAQS. Connecticut submitted on-road MVEBs for the
Southwestern CT Area of 575.8 tpy direct PM2.5 and 12,791.8
tpy NOX for 2017, and 516 tpy direct PM2.5 and
9,728.1 tpy NOX for 2025.
    EPA New England sent a letter to CT DEEP on January 8, 2013,
stating that the 2017 and 2025 MOVES2010 MVEBs in the June 22, 2012 SIP
submittal are adequate for transportation conformity purposes. On
February 5, 2013, (78 FR 8122) EPA notified the public through a
Federal Register notice of adequacy that EPA has found that the 2017
and 2025 MVEBs adequate for transportation conformity purposes. These
MVEBs became effective on February 20, 2013. For the Southwestern CT
Area, Connecticut must use the MVEBs in any future conformity
determination on or after the effective date of the notice of adequacy.
MVEBs are discussed further in section V.
3. Does the Southwestern CT Area have a fully approved applicable SIP
under Section 110(k) of the CAA?
    Upon final approval of the 2007 base-year emissions inventory, EPA
will have fully approved the Connecticut portion of the New York-N. New
Jersey-Long Island, NY-NJ-CT Area under section 110(k) of the CAA for
all requirements applicable for purposes of redesignation to attainment
for the 1997 annual and 2006 24-hour PM2.5 NAAQS. As noted
above, in this rulemaking action, EPA is proposing to approve the
Southwestern CT Area's 2007 base-year emissions inventory (submitted as
part of its maintenance plan) as meeting the requirement of section
172(c)(3) of the CAA for the 1997 annual and 2006 24-hour
PM2.5 NAAQS. Therefore, upon final approval of the 2007
base-year emissions inventory, Connecticut will have satisfied all
applicable requirements under part D of Title I of the CAA for the
Southwestern CT Area.

D. Are the air quality improvements in the Southwestern CT Area due to
permanent and enforceable reductions in emissions?

    EPA proposes to find that the state has demonstrated that the
observed air quality improvement in the Southwestern CT Area is due to
permanent and enforceable reductions in emissions resulting from
implementation of the SIP, federal measures, and other state-adopted
measures, listed in Table 1 above. As shown in the state's submittal
and supported by EPA rulemaking (see 75 FR 69589, November 15, 2010 and
77 FR 76867, December 31, 2012), the Area came into attainment with the
1997 annual PM2.5 standard based on PM2.5 data
for 2007-2009, and into attainment with the 2006 24-hour standard based
on PM2.5 data for the 2007-2009, 2008-2010, and 2009-2011
monitoring periods. The Area has remained in

attainment and the air quality has improved in the area. Attainment is
the direct result of permanent and enforceable emission reductions and
not favorable meteorology or economic downturn.
    Connecticut's redesignation request documents substantial emission
reductions in PM2.5 and PM2.5 precursors both in
upwind states and within Connecticut. For example, the state's request
notes that due to federal programs including EPA's acid rain program,
Ozone Transport Commission's NOX budget program, and EPA's
NOX SIP Call, emissions from EGUs from states impacting
Connecticut declined by 66 percent for NOX and by 48 percent
for SO2 between 2002 and 2009.
1. Federal Measures Implemented
    Reductions in PM2.5 and PM2.5 precursor
emissions (e.g., NOX and SO2) have occurred
statewide and in upwind states as a result of federal measures with
additional emission reductions expected to occur in the future. The
maintenance plan for the Southwestern CT Area lists post-2002 federal
measures (as well as state measures) that have reduced PM2.5
and PM2.5 precursor emissions from stationary and mobile
sources. These measures include the following:
(a) Tier 2 Emission Standards for Vehicles and Gasoline Sulfur
Standards
    These emission control requirements, which were published on
February 10, 2000 (65 FR 6698), result in lower NOX, and
SO2 emissions from new cars and light duty trucks, including
sport utility vehicles. The Federal rules were phased in between 2004
and 2009. EPA has estimated that, after phasing in the new
requirements, new vehicles emit less NOX in the following
percentages: Passenger cars (light duty vehicles)--77 percent; light
duty trucks, minivans, and sports utility vehicles--86 percent; and
larger sports utility vehicles, vans, and heavier trucks--69-95
percent. EPA expects fleet-wide average emissions to decline by similar
percentages as new vehicles replace older vehicles. The Tier 2
standards also reduced the sulfur content of gasoline to 30 parts per
million (ppm) beginning in January 2006, which reflects up to a 90
percent reduction in sulfur content.
(b) Heavy-Duty Diesel Rule and Gasoline Highway Vehicle Standards
    EPA published the heavy-duty diesel rule on January 18, 2001 (66 FR
5002). This rule, designed to reduce NOX and VOC emissions
from heavy-duty diesel and from gasoline highway vehicles, took effect
in 2004 and 2005, respectively. A second phase, which took effect in
2007, reduced PM2.5 emissions from heavy-duty highway
engines and further reduced the highway diesel fuel sulfur content to
15 ppm. The program is estimated to achieve a 90-percent reduction in
direct PM2.5 emissions and a 95-percent reduction in
NOX emissions for these new engines using low-sulfur diesel
fuel when compared to engines using higher sulfur diesel. The reduction
in fuel sulfur content also yielded an immediate reduction in
particulate sulfate emissions from all diesel vehicles.
(c) Motorcycle Exhaust Standards
    In 2004, EPA published a final rule to implement improved exhaust
emission standards on new highway motorcycles (69 FR 2398). These
standards apply to model-year 1978 and newer gasoline-fuels
motorcycles, and to later model-year motorcycles that use other fuel
types (1990 model year for methanol; 1997 model year for natural gas or
liquefied petroleum gas). For 2006 and later model-year new
motorcycles, the standards apply regardless of fuel. Starting with the
2006 model year, EPA re-defined Class I to include motorcycles with
engines smaller than 50 cubic centimeters. In addition, motorcycles
with the largest engines are subject to more stringent NOX
and hydrocarbon standards beginning with the 2010 model year.
(d) Non-Road Diesel Rule
    In June 2004, EPA published a new rule for large nonroad diesel
engines, such as those used in construction, agriculture, and mining,
to be phased in from 2008 to 2014 (69 FR 38958). The rule also reduced
the sulfur content in nonroad diesel fuel by over 99 percent. Prior to
2006, nonroad diesel fuel averaged approximately 3,400 ppm sulfur. This
rule limited nonroad diesel sulfur content to 500 ppm by 2006, with a
further reduction to 15 ppm by 2010. Because of the timing of the new
requirements, most reductions will occur during the maintenance period
for the Southwestern CT Area as the fleet of older non-road diesel
engines is gradually replaced with newer, lower-emitting engines.
However, the required reduction in fuel sulfur content yielded an
immediate reduction in sulfate particle emissions from all non-road
diesel vehicles.
(e) Non-Road Spark-Ignition Engines and Recreational Engine Standards
    On November 8, 2002, EPA promulgated emission standards for groups
of previously unregulated non-road engines (67 FR 68242). These
emission standards for several groups of nonroad engines, including
large spark-ignition engines, such as those used in forklifts and
airport ground-service equipment; recreational vehicles using spark-
ignition engines, such as off-highway motorcycles, all-terrain
vehicles, and snowmobiles; and recreational marine diesel engines.
Emission standards from large spark-ignition engines were implemented
in two tiers, with Tier 1 starting in 2004 and Tier 2 in 2007.
Recreational-vehicle emission standards were phased in from 2006
through 2012. Marine diesel engine standards were phased in from 2006
through 2009. With full implementation of the entire non-road spark-
ignition engine and recreational engine standards, an 80 percent
reduction in NOX is expected by 2020, as affected fleets are
gradually replaced.
(f) NOX SIP Call
    In October 1998, EPA issued the NOX SIP Call pursuant to
the CAA. This required 22 states (including Connecticut) and the
District of Columbia to reduce NOX emissions from EGUs
(i.e., power plants) and non-EGUs, such as industrial boilers, internal
combustion engines, and cement kilns. (63 FR 57356, October 27, 1998).
The program was intended to reduce emissions in states determined to be
significantly contributing to violations of the 1-hour ozone NAAQS in
downwind states. Affected states were required to comply with Phase I
of the SIP Call beginning in 2003/2004 and with Phase II beginning in
2007. EPA approved Connecticut's NOX SIP Call rule
(NOX Budget Program) on September 28, 1999 (64 FR 52233).
This program was incorporated into Connecticut's CAIR program (see
below) in September 2007. Emission reductions resulting from
regulations developed in response to the NOX SIP Call are
permanent and enforceable.
(g) CAIR and CSAPR
    EPA approved Connecticut's CAIR rules in 2007 (73 FR 4105,
September 4, 2007) as a control measure for reducing NOX
emissions from EGUs. As previously discussed, the Court's 2008 remand
of CAIR left the rule in place to ``temporarily preserve the
environmental values covered by CAIR'' until EPA replaced it with a
rule consistent with the Court's opinion, and the Court's August 2012
decision on CSAPR also left CAIR in effect until the legal challenges
to CSAPR are resolved. As noted, EPA believes it is appropriate to
allow states to rely on CAIR, and the

existing emissions reductions achieved by CAIR, as sufficiently
permanent and enforceable pending a valid replacement rule, for
purposes such as redesignation.
    Furthermore, as previously discussed, the air quality modeling
analysis conducted for CSAPR demonstrates that the Southwestern CT Area
would be able to attain the 1997 annual and 2006 24-hour
PM2.5 NAAQS even in the absence of either CAIR or CSAPR.
EPA's modeling projections show that all ambient monitors in the
Southwestern CT Area are expected to continue to maintain compliance in
the 2012 and 2014 ``no CAIR'' base cases. Therefore, none of the
ambient monitoring sites in the Southwestern CT Area are ``receptors''
that EPA projects will have future nonattainment problems or difficulty
maintaining the NAAQS.
2. SIP-Approved State Measures
    In addition to the federal control measures described above,
Connecticut is implementing several state programs that have
contributed to significant reductions in ambient levels of direct
PM2.5 and PM2.5 precursors. These are listed on
Table 1 and include, for example, regulations to reduce emissions of
SO2 and NOx from major stationary sources, including power
plants; low-sulfur fuel requirements; addition of a non-ozone season
NOx limit to all sources subject to the NOX Budget Program;
the addition of PM standards to certain fuel-burning equipment and
stationary reciprocating internal-combustion engines; updates to the
state's motor-vehicle emissions testing and Inspection and Maintenance
(I/M) programs; adoption of Low Emission Vehicle (LEV) standards; and
limits on NOx emissions from Municipal Waste Combustors. As noted in
Table 1, all of the regulations have been approved by EPA into the CT
SIP.
    Based on the information summarized above, Connecticut has
adequately demonstrated that the improvement in air quality is due to
permanent and enforceable emissions reductions. EPA concludes that
significant reductions result from federal requirements and regulation
of precursors under the NOx SIP Call and CAIR, which are expected to
continue into the future.

E. Does the Southwestern CT Area have a fully approved maintenance plan
pursuant to Section 175a of the CAA?

    In conjunction with its request to redesignate the Southwestern CT
Area to attainment status, Connecticut submitted a SIP revision to
provide for the maintenance of the 1997 annual and 2006 24-hour
PM2.5 NAAQS in the Southwestern CT Area until 2025.
1. Maintenance Plan Requirements
    Section 175 of the CAA sets forth the elements of a maintenance
plan for areas seeking redesignation from nonattainment to attainment.
Under CAA section 175A, the plan must demonstrate continued attainment
of the applicable NAAQS for at least 10 years after EPA approves an
area's redesignation. Eight years after the redesignation, Connecticut
must submit a revised maintenance plan demonstrating that attainment
will continue to be maintained for the 10 years following the initial
10-year period. To address the possibility of future NAAQS violations,
the maintenance plan must contain contingency measures, with a schedule
for implementation, as EPA deems necessary, to assure prompt correction
of any violations of the 1997 annual or 2006 24-hour PM2.5
NAAQS that occur after redesignation of the Area to attainment. The
Calcagni Memorandum dated September 4, 1992, provides additional
guidance on the content of a maintenance plan. This memorandum states
that a PM2.5 maintenance plan should include the following:
(1) An emissions inventory sufficient to ensure attainment; (2) a
demonstration that the plan ensures maintenance of the NAAQS for 10
years following approval of the redesignation request; (3) a commitment
to maintain an appropriate monitoring network; (4) a method to verify
continued attainment; and (5) a contingency plan to be implemented if
NAAQS violations occur during the maintenance period.
2. EPA's Analysis of the Southwestern CT Area Maintenance Plan
a. Attainment Emissions Inventory
    An attainment emissions inventory is a comprehensive inventory of
the actual emissions from sources within a nonattainment area for a
time period used to show that the area has come into attainment with
the NAAQS. Inventories used for Connecticut's PM2.5
redesignation request were developed as an extension to regional
efforts in the Mid-Atlantic/Northeast Visibility Union (MANE-VU) area
to create inventories for use in photochemical modeling for the 2008
ozone NAAQS and Regional Haze SIPs. For PM2.5 redesignation
efforts, MARAMA took the lead in coordinating with several states
(including Connecticut) to develop an inventory for 2025 to supplement
those already under development (2007, 2017 and 2020 inventories), as
well as to modify the 2007 inventory for PM2.5
redesignation. A summary of the inventory development process is given
below. For more information about how the inventories were developed,
as well as quality-assurance procedures, see Appendices in
Connecticut's PM2.5 Redesignation Request at http://www.regulations.gov: Docket number EPA-R01-OAR-2013-0020.
    In the Southwestern CT Area, compliance with the 1997 annual
PM2.5 NAAQS was achieved in 2001 and compliance with the 24-
hour NAAQS was achieved in 2008. Therefore, Connecticut chose 2007 as
the initial year for the attainment inventory. The end of the
maintenance period was established as 2025, with an interim year of
2017, which is consistent with the CAA section 175A(a) requirement that
the maintenance plan provide for maintenance of the NAAQS for at least
10 years after EPA approval of the redesignation request.
    Emission estimates were developed for EGU point sources, non-EGU
point sources, area sources, non-road mobile sources, and on-road
mobile sources. The MANE-VU PM2.5 redesignation inventories
were prepared only for the area classified as nonattainment for the
annual and 24-hour PM2.5 NAAQS (i.e., in Connecticut,
Fairfield County and New Haven Counties). The inventories were
developed at the county level for the area-source and mobile-source
categories and at the process level for point-source categories, then
summed to the county level. EPA concurs with Connecticut that the use
of annual inventories was also appropriate for demonstrating continued
compliance with the 24-hour PM2.5 NAAQS during the
maintenance period as analysis of monitoring data for the Southwestern
CT Area showed that elevated 24-hour PM2.5 levels occur in
multiple seasons (primarily summer and winter).
    Point source emissions--For the 2007 point-source inventory, CT
DEEP provided MARAMA with actual 2007 emissions for all EGU and non-EGU
point sources. EGU sources were considered to be only those sources
that report hourly emissions to EPA's Clean Air Markets Division (CAMD)
database. All other point sources (including non-EGUs in CAMD, small
non-CAMD EGUs and all other non-EGUs) were grouped as non-EGU point
sources. The 2007 inventory also included banked continuous emission
reduction credits (CERCs) for potential use as offsets in new source
review permits. MARAMA calculated components of PM emissions (i.e., PM-
primary, PM-filterable, and PM-condensable) that were missing from the
point-source inventory provided by Connecticut. For EGUs, MARAMA used
updated condensable emission factors; for non-EGUs,

MARAMA used a similar process to that used in developing the 2002 MANE-
VU Version 3 inventory. For information on PM2.5
augmentation processes, see Appendix A of Connecticut's
PM2.5 Redesignation Request at http://www.regulations.gov:
Docket number EPA-R01-OAR-2013-0020.
    To estimate EGU emissions for future years, MARAMA extrapolated the
2007 EGU emissions based on Annual Energy Outlook (AEO) electricity
generation projections. The appropriate AEO 2011 growth factor was
applied to the 2007 emissions to calculate a ``growth only'' emission
value for 2017 and 2025.
    MARAMA developed non-EGU point-source growth factors for
Connecticut using employment or fuel consumption projections, depending
on the source category. MARAMA extrapolated 2006-2016 employment
forecasts from the Connecticut Department of Labor through 2025 to
develop emission estimates for non-fuel burning sources such as
manufacturing operations. AEO fuel-use projections published in 2010 by
the U.S. Energy Information Administration were used to develop growth
factors for fuel-consuming sources.
    MARAMA examined adopted federal and regional control strategies to
determine those that would result in post-2007 emission reductions of
PM2.5 or PM2.5 precursors from non-EGU point
sources. They determined that the maximum achievable control technology
(MACT) standards for reciprocating internal combustion engines (RICE)
and for industrial/commercial/institutional (ICI) boilers and process
heaters will provide NOX or PM2.5 emission
reductions from several non-EGU source categories during the
maintenance period.
    Area source emissions--CT DEEP initially instructed MARAMA to use
EPA's 2008 National Emissions Inventory (NEI) emission values for all
area-source categories for the attainment year inventory. However,
during the quality-assurance effort, a number of categories were
discovered to be either missing from the 2008 NEI or to have used
incorrect emission-factor assumptions for Connecticut. Therefore,
substitutions were made from the 2005 NEI or from CT DEEP's draft 2005
periodic emission inventory (PEI). For residential wood combustion
(RWC), MARAMA's contractor used EPA's RWC tool with updated 2007 data
to produce emission estimates.
    MARAMA applied growth factors to the 2007 MANE-VU area-source
inventory to account for anticipated changes in fuel use, population
and economic activity during the maintenance period. For Connecticut,
growth factors were developed using the following sets of data: (1) AEO
New England region fuel consumption forecasts; (2) county-level
population projections; (3) state-level employment projections; (4)
county-level vehicle miles traveled (VMT) projections; and (5) EPA
projections for RWC.
    On-road mobile sources--EPA's MOVES2010 (MOtor Vehicle Emission
Simulator) is now the official model for estimating air-pollution
emissions from on-road mobile sources including buses, cars, trucks and
motorcycles for SIP purposes. This model replaces MOBILE6.2, EPA's
previous mobile source model. To assist in the transition to the new
model, EPA developed software tools to convert certain MOBILE6.2 inputs
for MOVES.
    CT DEEP assembled updated MOVES data sets and performed MOVES runs
with updated data for 2009, 2017 and 2025. Instead of developing
updated 2007 emission estimates, Connecticut used 2009 MOVES on-road
emission estimates in the PM2.5 attainment year inventory
because (1) EPA had previously approved 2009 transportation conformity
MVEBs for Connecticut that were determined using MOBILE6.2, and (2) the
use of the lower 2009 on-road emission estimates for 2007 ensured that
the total attainment year inventory across all source sectors will be
more conservative (i.e., lower) than if 2007 on-road emissions were
used. Since emissions through the end of the maintenance period must be
no higher than the attainment-year inventory, this approach provides
additional assurance that NAAQS compliance will continue through the
maintenance period.
    Nonroad mobile emissions--Non-road sources include internal
combustion engines used to propel marine vessels, airplanes, and
locomotives, or to operate equipment such as forklifts, lawn and garden
equipment, portable generators, etc. For activities other than marine
vessels, airplanes, and railroad locomotives (MAR), the inventory was
developed using the most current version of EPA's NONROAD model as
embedded in the National Mobile Inventory Model (NMIM). Because the
NONROAD model does not include emissions from MAR sources, these
emissions were estimated based on data and methodologies used in recent
EPA regulatory impact analyses.
    The emission inventories for Connecticut show that between 2002
(one of the years for which the Area's nonattainment designation was
based) and 2009, an attainment year, in-state emissions were reduced by
679 tons per year (4%) for direct PM2.5, 36,166 tons per
year (30%) for NOX, and 9,233 tons per year (29%) for
SO2.
    The emission inventories show that emissions of direct
PM2.5, SO2, and NOX are projected to
decrease by 1,371 tpy, 5,832 tpy, and 26,147 tpy, respectively, within
the 2-county Southwestern CT Area from the 2007 base year to the end of
the maintenance period in 2025. See Tables 5 and 6 below. In addition,
emissions inventories developed by MARAMA for addressing the 2012
PM2.5 NAAQS show that VOC emissions are projected to
decrease by about 32,695 tpy and ammonia emissions are projected to
decrease by 637 tpy statewide between 2007 and 2020. See Table 7 below.
While the MARAMA emissions inventories for VOC and ammonia are only
projected out to 2020, there is no reason to believe that this downward
trend will not continue through 2025. Given that the Southwestern CT
Area is already attaining the 1997 annual and 2006 24-hour
PM2.5 standards with the current level of source emissions,
the downward trend in the emissions inventories is consistent with
continued attainment. Indeed, projected emissions reductions for the
precursors that the state is addressing for purposes of the 1997 and
2006 PM2.5 NAAQS indicate that the area should continue to
attain both the annual and 24-hour NAAQS following the control
strategies that the state has already elected to pursue. Even if VOC
and ammonia emissions were to increase unexpectedly between 2020 and
2025, the overall emissions reductions projected in direct
PM2.5, SO2, and NOX would be
sufficient to offset any increases. For these reasons, EPA believes
that local emissions of all of the potential PM2.5
precursors will not increase to the extent that they will cause
monitored PM2.5 levels to violate the 1997 annual or 2006
24-hour PM2.5 standards during the maintenance period.

         Table 5--New Haven County, CT, Change in Emissions Between 2007 and 2025 in Tons per Year (tpy)
----------------------------------------------------------------------------------------------------------------
                                                                                PM2.5  2007-
                      Sector                        SO2  2007-2025  NOX  2007-2025       2025
--------------------------------------------------------------------------------------------------
Point (EGU).......................................          -424.3           -255.            -4.2
Point (Non-EGU)...................................             3.9           128.9             6.2
Area..............................................        -1,030.6          -328.0          -153.9
Marine Vessels, Airplanes, RR Locomotives (MAR)...          -691.6        -2,209.7          -117.0
Nonroad (NMIM)....................................          -166.5        -2,084.3          -142.3
Onroad (MOVES)....................................           -17.2        -7,962.6          -203.4
                                                   -------------------------------------------------------------
    Total.........................................        -2,326.3       -12,710.7          -614.7
----------------------------------------------------------------------------------------------------------------

         Table 6--Fairfield County, CT, Change in Emissions Between 2007 and 2025 in Tons per Year (tpy)
----------------------------------------------------------------------------------------------------------------
                                                                                PM2.5  2007-
                      Sector                        SO2  2007-2025  NOX  2007-2025       2025
--------------------------------------------------------------------------------------------------
Point (EGU).......................................        -1,889.9        -1,160.3          -152.0
Point (Non-EGU)...................................            25.2           668.1             4.9
Area..............................................        -1,082.1          -348.7          -163.9
Marine Vessels, Airplanes, RR Locomotives (MAR)...          -334.9        -1,688.8           -74.8
Nonroad (NMIM)....................................          -206.4        -2,590.8          -158.9
Onroad (MOVES)....................................           -17.9        -8,315.7          -211.7
                                                   -------------------------------------------------------------
    Total.........................................        -3,505.9       -13,436.2          -756.5
----------------------------------------------------------------------------------------------------------------

 Table 7--Connecticut, Change in Emissions Between 2007 and 2020 in tons
                           Per Year (tpy) \12\
------------------------------------------------------------------------
                                                                Ammonia
                      Sector                        VOC  2007-   (NH3)
                                                       2020    2007-2020
------------------------------------------------------------------------
Point (nonEGU)....................................        127          0
Point (EGU) \13\..................................        -58        -39
Area..............................................     -2,396         55
Non-road mobile...................................     -9,736          5
Commercial Marine Vessels.........................          1          0
Airports..........................................        -40          0
Railroad Locomotives..............................          9          0
On-road mobile \13\...............................    -20,602       -658
                                                   ---------------------
  Total...........................................    -32,695       -637
------------------------------------------------------------------------

    EPA concludes that Connecticut has adequately derived and
documented the 2007 attainment year and 2017 and 2025 projected-year
emissions of PM2.5 and PM2.5 precursors,
including PM2.5, SO2, NOX, VOC, and
ammonia for the Southwestern CT Area.
---------------------------------------------------------------------------

    \12\ These emissions estimates are from the emissions
inventories developed by MARAMA for use in part in addressing NAAQS
requirements for the 2012 PM2.5 standards. See Appendix C
of Connecticut's June 22, 2012 redesignation request, which is
available in the docket for today's rulemaking action.
    \13\ MARAMA's VOC and NH3 emission estimates did not
include estimates for the EGU and on-road mobile sectors. Emission
values in this table represent values taken from EPA's regulatory
impact analysis for the PM NAAQS.
---------------------------------------------------------------------------

b. Maintenance Demonstration
    As mentioned above, as required by section 175A of the CAA,
Connecticut's June 22, 2012 redesignation request included a 10-year
maintenance plan for the Southwestern CT Area. This plan demonstrates
maintenance by showing that future emissions of PM2.5 and
PM2.5 precursors remain at or below attainment-year emission
levels for both the 1997 annual and 2006 24-hour PM2.5
NAAQS. A maintenance demonstration need not be based on modeling. See
Wall v. EPA, supra; Sierra Club v. EPA, supra. See also 66 FR at 53099-
53100; 68 FR at 25430-32.
    Connecticut used 2007 as the base year, 2017 as the interim year,
and 2025 as the last year of the maintenance plan. (In addition, per 40
CFR Part 93, a MVEB must be established for the last year of the
maintenance plan. MVEBs are discussed in Section V below.) Table 8
shows the emissions inventories for 2007, 2017, and 2025 from
Connecticut's June 22, 2012 submittal for the Southwestern CT Area for
direct PM2.5 and the Area's principal PM2.5
precursors, SO2, and NOX. The emissions inventory
shows a downward trend in PM2.5 and PM2.5
precursor emissions from 2007 through 2017, and continuing on until
2025. Between 2007 and 2025, emissions are expected to decrease by 43
percent for SO2, 55 percent for NOX, and 22
percent for PM2.5. As discussed above in the section on
``attainment emissions inventory,'' MARAMA's emissions inventories show
that VOC emissions are projected to decrease by about 32,695 tpy and
ammonia emissions are projected to decrease by 637 tpy statewide
between 2007 and 2020. See Table 7 above. While the MARAMA emissions
inventories for VOC and ammonia are only projected out to 2020, there
is no reason to believe that this downward trend will not continue
through 2025.

 Table 8--Comparison of 2007, 2017, and 2025 SO2, NOX, and Direct PM2.5 Emission Totals for the Southwestern CT
                                                      Area
                                                    [in tpy]
----------------------------------------------------------------------------------------------------------------
                                                                        SO2             NOX            PM2.5
----------------------------------------------------------------------------------------------------------------
2007 (attainment)...............................................        13,615.9        50,339.1         6,113.0
2017 (interim)..................................................         7,909.0        29,501.3         5,029.1
2025 (maintenance)..............................................         7,783.7        24,192.2         4,741.7

2007 to 2025 (change)...........................................        -5,832.2       -26,146.9        -1,371.2
                                                                          (-43%)          (-55%)          (-22%)
----------------------------------------------------------------------------------------------------------------

    In addition, current air-quality design values (DVs) and air-
quality modeling show continued maintenance of both the 1997 annual and
2006 24-hour PM2.5 standards during the maintenance period.
As shown in Table 9 below, the most recent DVs for the Southwestern CT
Area are well below the 1997 annual PM2.5 NAAQS of 15 [mu]g/
m\3\ and the 2006 24-hour PM2.5 NAAQS of 35 [mu]g/m\3\.

                              Table 9--Air-Quality (PM2.5) Design Values ([mu]g/m\3\) for Fairfield and New Haven Counties
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            1997 annual     1997 annual     1997 annual     2006 24-hr      2006 24-hr      2006 24-hr
                         County                            NAAQS  2007-    NAAQS  2008-    NAAQS  2009-    NAAQS  2007-    NAAQS  2008-    NAAQS  2009-
                                                               2009            2010            2011            2009            2010            2011
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fairfield...............................................            11.3            10.0             9.4              31              28              26
New Haven...............................................            11.4            10.3             9.6              31              29              28
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The modeling analysis conducted for the Regulatory Impact Analysis
for the 2012 PM2.5 NAAQS \14\ indicates that DVs for the
Southwestern CT Area are expected to continue to decline through 2020.
In the RIA for the 2012 PM2.5 NAAQS, the highest annual DV
projected for 2020 is 8.79 [mu]g/m\3\ for Fairfield County and 8.62
[mu]g/m\3\ for New Haven County. The highest 24-hour DV projected for
2020 is 22.27 [mu]g/m\3\ for Fairfield County and 21.78 [mu]g/m\3\ for
New Haven County. Given that precursor emissions are projected to
decrease through 2025, it is reasonable to conclude that monitored
PM2.5 levels in this area will also continue to decrease
through 2025.
---------------------------------------------------------------------------

    \14\ The ``Regulatory Impact Analysis for the Proposed Revisions
to the National Ambient Air Quality Standards for Particulate
Matter'' is available in the docket for today's rulemaking action.
---------------------------------------------------------------------------

    Thus, EPA believes that there is ample justification to conclude
that the Southwestern CT Area should be redesignated, even taking into
consideration the emissions of other precursors potentially relevant to
PM2.5. After consideration of the DC Circuit's January 4,
2013 decision, and for the reasons set forth in this notice, EPA
proposes to approve the State's maintenance plan and its request to
redesignate the Southwestern CT Area to attainment for the 1997 annual
PM2.5 standard and for the 2006 24-hour PM2.5
standard.
c. Monitoring Network
    Connecticut currently operates seven PM2.5 monitors in
the Connecticut portion of the NY-NJ-CT PM2.5 nonattainment
area. Three are located in New Haven County, and four are in Fairfield
County. In its June 22, 2012 SIP submittal, Connecticut committed to
continue to operate all seven of its monitors in accordance with 40 CFR
part 58 and to enter all data into the AQS in accordance with federal
guidelines. Connecticut has, therefore, addressed the requirement for
continued PM2.5 monitoring in the Southwestern CT Area.
d. Verification of Continued Attainment
    The state has the legal authority to enforce and implement the
requirements of the PM2.5 maintenance plan. This includes
the authority to adopt, implement, and enforce any subsequent emission-
control contingency measures determined to be necessary to correct
future PM2.5 attainment problems. To implement the
PM2.5 maintenance plan, the state will continue to monitor
PM2.5 levels in the Southwestern CT Area. Connecticut has
also committed to track the progress of the maintenance demonstration
by periodically updating its emission inventory. The update will be
based, in part, on the annual update of the National Emissions
Inventory (NEI), and will indicate new source growth and other changes
from the attainment inventory, including any changes in vehicle miles
traveled or in traffic patterns.
e. The Maintenance Plan's Contingency Measures
    The contingency plan provisions for maintenance plans are designed
to promptly correct a violation of the NAAQS that occurs after
redesignation. Section 175A of the CAA requires that a maintenance plan
include such contingency measures as EPA deems necessary to ensure that
a state will promptly correct a violation of the NAAQS that occurs
after redesignation. The maintenance plan should identify the events
that would ``trigger'' the adoption and implementation of a contingency
measure(s), the contingency measure(s) that would be adopted and
implemented, and the schedule indicating the time frame by which the
state would adopt and implement the measure(s).
    As required by section 175A of the CAA, Connecticut's maintenance
plan outlines the procedures for the adoption and implementation of
contingency measures to further reduce emissions should a violation
occur. Connecticut's contingency measures include a Warning Level
Response and an Action Level Response. For a Warning Level Response, CT
DEEP will track air-quality monitoring data and emission inventories to
identify when the Area is at risk of violating either the 1997 annual
or 2006 24-hour PM2.5 NAAQS. The Warning Level Response will
be triggered if either a single year's 98th percentile daily value
exceeds 35 [mu]g/m\3\ or a single year's annual average exceeds 15
[mu]g/m\3\ at any CT DEEP site in the maintenance area and is verified.
CT DEEP will examine available information to identify contributing
factors such as atypical meteorological conditions, exceptional events,
local changes in source activity, or source malfunctions or
noncompliance.
    An Action Level Response will be triggered if a verified violation
of either PM2.5 NAAQS occurs. If an Action Level Response is
triggered, as required by

CAA 175A(d), CT DEEP commits to implementing all measures that were
contained in the SIP before the Southwestern CT Area was redesignated
to attainment. CT DEEP also commits to pursuing adoption (and submittal
to EPA) and implementation of any appropriate regulatory revisions
within 18 to 24 months after the verified violation. See letter to EPA
dated June 6, 2013, available in the docket for today's action.
    CT DEEP will select contingency measures based on cost
effectiveness, emission reduction potential, economic and social
considerations, or other appropriate factors. Stakeholder input will be
solicited before final selection of any contingency measures.
Connecticut's candidate contingency measures include, but are not
limited to, the following:
     Control measures already adopted, but designed to produce
additional reductions after the verified violation occurred (e.g.,
mobile source measures that involve fleet turnover);
     New control measures that may be adopted for other
purposes (e.g., Tier 3 or CALEV3);
     Alternative fuel and/or diesel retrofit programs for fleet
vehicle operations;
     New or more stringent PM2.5, NOX or
SO2 controls on stationary sources;
     Wood stove change out program;
     ``No burn'' days during cold weather inversion events;
     Enhanced idle restrictions; and
     Transportation control measures, selected in consultation
with Connecticut Department of Transportation (CT DOT) and affected
local metropolitan planning organizations (e.g., traffic flow
improvements, transit improvements, trip reduction programs, other new
or innovative transportation measures).
    In addition, NOX reductions from fleet turnover are
happening each year automatically, without any additional rulemaking.
    It is unlikely, however, that Connecticut will violate either
PM2.5 standard. As shown in Table 9 above, the design values
in both Fairfield and New Haven Counties are decreasing. The design
values for these counties are 9.4 and 9.6 [mu]g/m\3\, respectively,
compared to an annual standard of 15.0 [mu]g/m\3\; they are 26 and 28
[mu]g/m\3\, respectively, compared to a 24-hour standard of 35.0 [mu]g/
m\3\. If either county were to violate one of the PM2.5
standards, we would negotiate a timeline and schedule through our
regular annual grant negotiations for which we develop priority and
commitment (P&C) lists each year.
    For the reasons discussed above, EPA believes that the Southwestern
CT Area maintenance plan adequately addresses the five basic components
of a maintenance plan: Attainment inventory; maintenance demonstration;
monitoring network; verification of continued attainment; and a
contingency plan. Therefore, EPA is proposing to approve the
maintenance plan SIP revision submitted by Connecticut for the
Southwestern CT Area as meeting the requirements of CAA section 175A.

V. MVEBs

1. How are MVEBs developed and what are the MVEBs for the Southwestern
CT Area?
    As part of its June 22, 2012 redesignation request, CT DEEP
requested withdrawal of the SIP-approved 2009 motor vehicle emissions
budgets (MVEBs) prepared using MOBILE6.2 and approval of 2017 and 2025
MVEBs prepared using MOVES2010. Under the CAA, states are required to
submit, at various times, control strategy SIP revisions and
maintenance plans for nonattainment areas and for areas seeking
redesignation to attainment for a given NAAQS. These emission-control-
strategy SIP revisions (e.g., RFP and attainment demonstration SIP
revisions) and maintenance plans create MVEBs based on on-road mobile
source emissions for the relevant criteria pollutants and/or their
precursors, where appropriate, to address pollution from on-road
transportation sources. The MVEBs are the portions of the total
allowable emissions that are allocated to on-road vehicle use that,
together with emissions from all other sources in the area, will
provide for attainment, RFP, or maintenance, as applicable. The budget
serves as a ceiling on emissions from an area's planned transportation
system. Under 40 CFR part 93, a MVEB for an area seeking a
redesignation to attainment is established for the last year of the
maintenance plan. See the September 27, 2011 notice of direct final
approval for a more complete discussion of MVEBs (76 FR 59512).
    EPA's substantive criteria for determining the adequacy of MVEBs
are set out in 40 CFR 93.118(e)(4). Additionally, to approve a MVEB,
EPA must complete a thorough review of the SIP, in this case the
PM2.5 maintenance plan, and conclude that with the projected
level of motor vehicle and all other emissions, the SIP will achieve
its overall purpose, in this case providing for maintenance of the 1997
annual and 2006 24-hour PM2.5 standards.
    EPA's process for determining adequacy of a MVEB consists of three
basic steps: (1) Providing public notification of a SIP submission; (2)
providing the public the opportunity to comment on the MVEB during a
public comment period; and, (3) EPA taking action on the MVEB. The
process for determining the adequacy of submitted SIP MVEBs is codified
at 40 CFR 93.118.
    The availability of the SIP submission with these 2017 and 2025
MVEBs was announced for public comment on EPA's adequacy Web page on
November 27, 2012 at: http://www.epa.gov/otaq/stateresources/transconf/currsips.htm. The EPA public comment period on adequacy of the 2017 and
2025 MVEBs for the Southwestern CT Area closed on December 27, 2012.
EPA did not receive any comments. EPA sent a letter to CT DEEP on
January 8, 2013, stating that the 2017 and 2025 MOVES2010 motor vehicle
emissions budgets in the June 22, 2012 SIP are adequate for