[Federal Register Volume 84, Number 97 (Monday, May 20, 2019)]
[Proposed Rules]
[Pages 22787-22805]
[FR Doc No: 2019-09928]

-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-HQ-OAR-2018-0170; FRL-9993-55-OAR]
RIN 2060-AU04

Response to Clean Air Act Section 126(b) Petition From New York

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of proposed action on petition.

-----------------------------------------------------------------------

SUMMARY: The Environmental Protection Agency (EPA) is proposing to deny
a Clean Air Act (CAA or Act) petition submitted by the state of New
York on March 12, 2018. The petition requests that the EPA make a
finding that emissions from a group of hundreds of identified sources
in nine states (Illinois, Indiana, Kentucky, Maryland, Michigan, Ohio,
Pennsylvania, Virginia and West Virginia) significantly contribute to
nonattainment and interfere with maintenance of the 2008 and 2015 ozone
national ambient air quality standards (NAAQS) in Chautauqua County and
the New York

Metropolitan Area (NYMA) in violation of the good neighbor provision.
The EPA proposes to deny the petition because New York has not met its
statutory burden to demonstrate, and the EPA has not independently
found, that the group of identified sources emits or would emit in
violation of the good neighbor provision for the 2008 or 2015 ozone
NAAQS in Chautauqua County and the NYMA.

DATES:
    Comments. Comments must be received on or before July 15, 2019.
    Public hearing: The EPA will hold a public hearing on this proposal
on June 11, 2019, in Washington DC. Please refer to ADDRESSES for
additional information on the comment period and public hearing.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2018-0170, at http://www.regulations.gov. Follow the online
instructions for submitting comments. Once submitted, comments cannot
be edited or removed from Regulations.gov. The EPA may publish any
comment received to its public docket. Do not submit electronically any
information you consider to be Confidential Business Information (CBI)
or other information whose disclosure is restricted by statute.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and should include discussion of all points you wish to make. The EPA
will generally not consider comments or comment contents located
outside of the primary submission (e.g., on the Web, Cloud, or other
file sharing system). For additional submission methods, the full EPA
public comment policy, information about CBI or multimedia submissions,
and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets. Certain other material,
such as copyrighted material, will not be placed on the internet but
may be viewed, with prior arrangement, at the EPA Docket Center.
Publicly available docket materials are available either electronically
in www.regulations.gov or in hard copy at the Air and Radiation Docket
and Information Center, EPA/DC, EPA William Jefferson Clinton West
Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC. The
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Public
Reading Room is<PHONE_NUMBER> and the telephone number for the Air and
Radiation Docket and Information Center is<PHONE_NUMBER>. For
additional information about the EPA's public docket, visit the EPA
Docket Center homepage at: http://www.epa.gov/epahome/dockets.htm.
    Public hearing: The June 11, 2019, public hearing will be held at
the EPA, William Jefferson Clinton East Building, Room 1117A, 1201
Constitution Avenue NW, Washington, DC 20004. The public hearing will
convene at 9:00 a.m. and end at 6:00 p.m. Eastern Time (ET) or 1 hour
after the last registered speaker has spoken. The EPA will make every
effort to accommodate all individuals interested in providing oral
testimony. A lunch break is scheduled from 12:00 p.m. until 1:00 p.m.
Please note that this hearing will be held at a U.S. government
facility. Individuals planning to attend the hearing should be prepared
to show valid picture identification to the security staff to gain
access to the meeting room. The REAL ID Act, passed by Congress in
2005, established new requirements for entering federal facilities.
These requirements took effect July 21, 2014. If your driver's license
is issued by American Samoa, you must present an additional form of
identification to enter the federal building where the public hearing
will be held. Acceptable alternative forms of identification include:
Federal employee badges, passports, enhanced driver's licenses and
military identification cards. For additional information for the
status of your state regarding REAL ID, go to http://www.dhs.gov/real-id-enforcement-brief. In addition, you will need to obtain a property
pass for any personal belongings you bring with you. Upon leaving the
building, you will be required to return this property pass to the
security desk. No large signs will be allowed in the building, and
demonstrations will not be allowed on federal property for security
reasons.
    If you would like to present oral testimony at the hearing, please
notify Ms. Pamela Long, U.S. Environmental Protection Agency, Office of
Air Quality Planning and Standards, Air Quality Policy Division, (C504-
01), Research Triangle Park, NC 27711, telephone<PHONE_NUMBER>, fax
number<PHONE_NUMBER>, email address<EMAIL_ADDRESS>no later than
4:00 p.m. ET on June 7, 2011. Ms. Long will arrange a general time slot
for you to speak. The EPA will make every effort to follow the schedule
as closely as possible on the day of the hearing.
    Oral testimony will be limited to 5 minutes for each commenter. The
EPA encourages commenters to provide the EPA with a copy of their oral
testimony electronically (via email) or in hard copy form. Commenters
should notify Ms. Long if they need specific translation services for
non-English speaking commenters.
    The hearing schedule, including the list of speakers, will be
posted on the EPA's Web at site https://www.epa.gov/ozone-pollution/ozone-national-ambient-air-quality-standards-naaqs-section-126-petitions prior to the hearing. Verbatim transcripts of the hearing and
written statements will be included in the docket for the action.
    The public hearing will provide interested parties the opportunity
to present data, views or arguments concerning the EPA's proposed
response to the petition from New York. The EPA may ask clarifying
questions during the oral presentations but will not respond to the
presentations at that time. Written statements and supporting
information that are submitted during the comment period will be
considered with the same weight as any oral comments and supporting
information presented at the public hearing. Written comments must be
postmarked by the last day of the comment period.

FOR FURTHER INFORMATION CONTACT: For additional information regarding
this proposed action, please contact: Beth W. Palma, U.S. EPA, Office
of Air Quality Planning and Standards, Air Quality Policy Division,
Mail Code C539-04, Research Triangle Park, NC 27711, telephone (919)
541-5432, email at<EMAIL_ADDRESS>For information on the
public hearing or to register to speak at the hearing, contact Ms.
Pamela Long, U.S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, Air Quality Planning Division, Mail
Code C504-01, Research Triangle Park, NC 27711, telephone (919) 541-
0641, fax number<PHONE_NUMBER>, email at<EMAIL_ADDRESS>(preferred
method for registering).

SUPPLEMENTARY INFORMATION:  The information in this document is
organized as follows:

I. General Information
II. Executive Summary of the EPA's Proposed Decision on the CAA
Section 126(b) Petition From New York
III. Background and Legal Authority
    A. Ground-Level Ozone and the Interstate Transport of Ozone
    B. CAA Sections 110 and 126
    C. The EPA's Historical Approach To Addressing Interstate
Transport of Ozone Under the Good Neighbor Provision
    D. The CAA Section 126(b) Petition From New York
IV. The EPA's Proposed Decision on the CAA Section 126(b) Petition
From New York

    A. The EPA's Approach for Granting or Denying CAA Section 126(b)
Petitions Regarding the 2008 and 2015 8-Hour Ozone NAAQS
    B. The EPA's Evaluation of Whether the Petition Is Sufficient To
Support a CAA Section 126(b) Finding
V. Conclusion
VI. Judicial Review
VII. Statutory Authority

I. General Information

    Throughout this document wherever ``we,'' ``us,'' ``our'' or
``Agency'' is used, we mean the United States (U.S.) EPA.

Where can I get a copy of this document and other related information?

    The EPA has established a docket for this action under Docket ID
No. EPA-HQ-OAR-2018-0170 (available at http://www.regulations.gov). The
EPA has made available information related to the proposed action and
the public hearing at website: https://www.epa.gov/ozone-pollution/ozone-national-ambient-air-quality-standards-naaqs-section-126-petitions.

II. Executive Summary of the EPA's Proposed Decision on the CAA Section
126(b) Petition From New York

    In March 2018, the state of New York submitted a petition
requesting that the EPA make a finding pursuant to CAA section 126(b)
that emissions from over 350 facilities in nine states significantly
contribute to nonattainment and/or interfere with maintenance of the
2008 and 2015 ozone NAAQS in violation of CAA section
110(a)(2)(D)(i)(I), otherwise known as the good neighbor provision. For
the reasons explained in this notice, the EPA is proposing to deny the
petition because New York has not met its statutory burden to
demonstrate that the group of sources identified in the petition emits
or would emit in violation of the good neighbor provision for the 2008
or 2015 ozone NAAQS in either Chautauqua County or the NYMA.
    The EPA is evaluating the petition consistent with the same four-
step interstate transport framework that the EPA has used in previous
regulatory actions addressing regional ozone transport problems. The
EPA is, therefore, using this framework to evaluate whether the
petition meets the standard to demonstrate under CAA section 126(b)
that the sources emit or would emit in violation of the good neighbor
provision. The EPA's proposed denial rests on both the first and third
steps of this framework. With respect to the 2008 and 2015 ozone NAAQS
in Chautauqua County, the EPA is proposing to deny the petition at step
1 of the framework (i.e., whether there will be a downwind air quality
problem relative to the relevant NAAQS) based on the conclusion that
the petition has not identified, and the EPA has not independently
found, relevant air quality problems. With respect to the 2008 ozone
NAAQS in the NYMA, the EPA is similarly proposing to deny the petition
based on the conclusion that the petition has not identified, and the
EPA has not independently found, relevant air quality problems. Thus,
the EPA is proposing to find as to these areas and NAAQS that the
petition has not met its burden at step 1 of the four-step interstate
transport framework. Thus, the group of identified sources neither
emits nor would emit pollution in violation of the good neighbor
provision. With respect to the 2015 ozone NAAQS in the NYMA, the EPA
has identified a relevant downwind air quality problem, and, thus, the
EPA is not proposing a denial at step 1 as to this portion of the
petition.
    The EPA is additionally proposing to deny the petition as to all
areas and NAAQS at step 3 of the framework (i.e., whether, considering
cost and air-quality factors, emissions from sources in the named
state(s) will significantly contribute to nonattainment or interfere
with maintenance of a NAAQS at a receptor in another state). The EPA is
proposing to find that material elements in the petition's assessment
of whether the sources may be further controlled through implementation
of cost-effective controls are insufficient and, thus, New York has not
met its step 3 burden to demonstrate that the named sources currently
emit or would emit in violation of the good neighbor provision with
respect to the relevant ozone NAAQS. As to the claims in the petition
regarding Chautauqua County (for both NAAQS) and the NYMA (for the 2008
ozone NAAQS), this provides an independent basis for denial in addition
to the proposed denial under step 3. The EPA is taking comment on
whether to also deny the petition because the petitioner has not
provided justification for the proposition that identification of such
a large, undifferentiated number of sources located in numerous upwind
states constitutes a ``group of stationary sources'' within the context
of CAA section 126(b).
    Section III of this notice provides background information
regarding the EPA's approach to addressing the interstate transport of
ozone under CAA sections 110(a)(2)(D)(i)(I) and 126(b) and provides a
summary of the relevant issues raised in New York's CAA section 126(b)
petition. Section IV of this notice details the EPA's proposed action
to deny the petition, including an explanation of the EPA's approach
for granting or denying CAA section 126(b) petitions regarding the 2008
and 2015 8-hour ozone NAAQS and the EPA's evaluation of the sufficiency
of New York's petition, identifying technical insufficiencies in the
petition and explaining how the EPA's own analysis informs its
evaluation of the claims in the petition.

III. Background and Legal Authority

A. Ground-Level Ozone and the Interstate Transport of Ozone

    On March 12, 2008, the EPA promulgated a revision to the ground-
level ozone NAAQS, lowering both the primary and secondary standards to
75 parts per billion (ppb).\1\ On October 1, 2015, the EPA further
revised the ground-level ozone NAAQS to 70 ppb.\2\
---------------------------------------------------------------------------

    \1\ See National Ambient Air Quality Standards for Ozone, Final
Rule, 73 FR 16436 (March 27, 2008).
    \2\ See National Ambient Air Quality Standards for Ozone, Final
Rule, 80 FR 65292 (October 26, 2015).
---------------------------------------------------------------------------

    In this proposal, consistent with previous rulemakings described in
Section III.C.2, the EPA relies on analyses that reflect the regional
nature of transported ground-level ozone pollution. Ground-level ozone
is not emitted directly into the air but is a secondary air pollutant
created by chemical reactions between nitrogen oxides (NOX),
carbon monoxide (CO), methane (CH4), and non-methane
volatile organic compounds (VOCs) in the presence of sunlight.
Emissions from mobile sources, electric generating units (EGUs),
industrial facilities, gasoline vapors, and chemical solvents are some
of the major anthropogenic sources of ozone precursors. The potential
for ground-level ozone formation increases during periods with warmer
temperatures and stagnant air masses. Therefore, ozone levels are
generally higher during the summer months.3 4 Ground-level
ozone concentrations and temperature are highly correlated in the
eastern U.S., with observed ozone increases of 2-3 ppb per degree
Celsius reported.\5\
---------------------------------------------------------------------------

    \3\ Rasmussen, D.J. et al. (2012). Surface ozone-temperature
relationships in the eastern U.S.: A monthly climatology for
evaluating chemistry-climate models. Atmospheric Environment 47:
142-153.
    \4\ High ozone concentrations have also been observed in cold
months, where a few areas in the western U.S. have experienced high
levels of local VOC and NOX emissions that have formed
ozone when snow is on the ground and temperatures are near or below
freezing.
    \5\ Bloomer, B.J., J.W. Stehr, C.A. Piety, R.J. Salawitch, and
R.R. Dickerson (2009). Observed relationships of ozone air pollution
with temperature and emissions, Geophys. Res. Lett., 36, L09803.
---------------------------------------------------------------------------

    Precursor emissions can be transported downwind directly or, after

transformation in the atmosphere, as ozone. Studies have established
that ozone formation, atmospheric residence, and transport can occur on
a regional scale (i.e., across hundreds of miles) over much of the
eastern U.S. Thus, in any given location, ozone pollution levels are
affected by a combination of local emissions and emissions from upwind
sources. Numerous observational studies have demonstrated the transport
of ozone and its precursors and the impact of upwind emissions on high
concentrations of ozone pollution.\6\
---------------------------------------------------------------------------

    \6\ For example, Bergin, M.S. et al. (2007). Regional air
quality: Local and interstate impacts of NOX and
SO2 emissions on ozone and fine particulate matter in the
eastern United States. Environmental Sci & Tech. 41: 4677-4689.
---------------------------------------------------------------------------

    The EPA concluded in several previous rulemakings (summarized in
Section III.C.2) that interstate ozone transport can be an important
component of peak ozone concentrations during the summer ozone season
and that NOX control strategies are effective for reducing
regional-scale ozone transport. Model assessments have looked at
impacts on peak ozone concentrations after potential emissions
reduction scenarios for NOX and VOCs for NOX-
limited and VOC-limited areas. For example, Jiang and Fast concluded
that NOX emissions reduction strategies are effective in
lowering ozone mixing ratios in urban areas and Liao et al. showed that
NOX reductions result in lower peak ozone concentrations in
non-attainment areas in the Mid-Atlantic.7 8
---------------------------------------------------------------------------

    \7\ Jiang, G.; Fast, J.D. (2004). Modeling the effects of VOC
and NOX emissions sources on ozone formation in Houston
during the TexAQS 2000 field campaign. Atmospheric Environment 38:
5071-5085.
    \8\ Liao, K. et al. (2014) Impacts of interstate transport of
pollutants on high ozone events over the Mid-Atlantic United States.
Atmospheric Environment 84: 100-112.
---------------------------------------------------------------------------

    Studies have found that NOX emissions reductions can be
effective in reducing ozone pollution as quantified by the form of the
2008 ozone standard (8-hour peak concentrations). Specifically, studies
have found that NOX emissions reductions from EGUs, mobile
sources, and other source categories can be effective in reducing the
upper-end of the cumulative ozone distribution in the summer on a
regional scale.\9\ Analysis of air quality monitoring data trends shows
reductions in summertime ozone concurrent with implementation of
NOX reduction programs.\10\ Gilliland et al. examined the
NOX State Implementation Plan (SIP) Call,\11\ discussed in
more detail in Section III.C.2, and presented reductions in observed
versus modeled ozone concentrations in the eastern U.S. downwind from
major NOX sources.\12\ The results showed significant
reductions in ozone concentrations (10-25 percent) from observed
measurements (CASTNET and AQS) \13\ between 2002 and 2005, linking
reductions in EGU NOX emissions from upwind states with
ozone reductions downwind of the major source areas.\14\ Additionally,
G[eacute]go et al. showed that ground-level ozone concentrations were
significantly reduced after implementation of the NOX SIP
Call.\15\ Thus, these studies support the EPA's continued focus on
regional and seasonal NOX control strategies to address
regional interstate ozone pollution transport.
---------------------------------------------------------------------------

    \9\ Hidy, G.M. and Blanchard C.L. (2015). Precursor reductions
and ground-level ozone in the Continental United States. J. of Air &
Waste Management Ass'n 65, 10.
    \10\ Simon, H. et al. (2015). Ozone trends across the United
States over a period of decreasing NOX and VOC emissions.
Environmental Science & Technology 49, 186-195.
    \11\ See Finding of Significant Contribution and Rulemaking for
Certain States in the Ozone Transport Assessment Group Region for
Purposes of Reducing Regional Transport of Ozone (NOX SIP
Call). 63 FR 57356 (October 27, 1998).
    \12\ Gilliland, A.B. et al. (2008). Dynamic evaluation of
regional air quality models: Assessing changes in O3
stemming from changes in emissions and meteorology. Atmospheric
Environment 42: 5110-5123.
    \13\ CASTNET is the EPA's Clean Air Status and Trends Network.
AQS is the EPA's Air Quality System.
    \14\ Hou, Strickland & Liao (2015). Contributions of regional
air pollutant emissions to ozone and fine particulate matter-related
mortalities in eastern U.S. urban areas. Environmental Research 137:
475-484.
    \15\ G[eacute]go et al. (2007). Observation-based assessment of
the impact of nitrogen oxides emission reductions on O3
air quality over the eastern United States. J. of Applied
Meteorology and Climatology 46: 994-1008.
---------------------------------------------------------------------------

B. CAA Sections 110 and 126

    The statutory authority for this action is provided by CAA sections
126 and 110(a)(2)(D)(i). Section 126(b) of the CAA provides, among
other things, that any state or political subdivision may petition the
Administrator of the EPA to find that any major source or group of
stationary sources in an upwind state emits or would emit any air
pollutant in violation of the prohibition of CAA section
110(a)(2)(D)(i), referred to as the good neighbor provision of the
Act.\16\ Petitions submitted pursuant to this section are commonly
referred to as CAA section 126(b) petitions. Similarly, findings by the
Administrator, pursuant to this section, that a source or group of
sources emits air pollutants in violation of the CAA section
110(a)(2)(D)(i) prohibition are commonly referred to as CAA section
126(b) findings.
---------------------------------------------------------------------------

    \16\ The text of CAA section 126 as codified in the U.S. Code
cross-references section 110(a)(2)(D)(ii) instead of section
110(a)(2)(D)(i). The courts have confirmed that this is a
scrivener's error and the correct cross-reference is to CAA section
110(a)(2)(D)(i). See Appalachian Power Co. v. EPA, 249 F.3d 1032,
1040-44 (D.C. Cir. 2001).
---------------------------------------------------------------------------

    CAA section 126(c) explains the effect of a CAA section 126(b)
finding and establishes the conditions under which continued operation
of a source subject to such a finding may be permitted. Specifically,
CAA section 126(c) provides that it is a violation of section 126 of
the Act and of the applicable SIP: (1) For any major proposed new or
modified source subject to a CAA section 126(b) finding to be
constructed or operate in violation of the prohibition of CAA section
110(a)(2)(D)(i) or (2) for any major existing source for which such a
finding has been made to stay in operation more than 3 months after the
date of the finding. The statute, however, also gives the Administrator
discretion to permit the continued operation of a source beyond 3
months if the source complies with emissions limitations and compliance
schedules provided by the EPA to bring about compliance with the
requirements contained in CAA sections 110(a)(2)(D)(i) and 126 as
expeditiously as practicable, but in any event no later than 3 years
from the date of the finding.
    Section 110(a)(2)(D)(i) of the CAA requires states to prohibit
certain emissions from in-state sources if such emissions impact the
air quality in downwind states. Specifically, CAA sections 110(a)(1)
and 110(a)(2)(D)(i)(I) require all states, within 3 years of
promulgation of a new or revised NAAQS, to submit SIPs that contain
adequate provisions prohibiting any source or other type of emissions
activity within the state from emitting any air pollutant in amounts
which will contribute significantly to nonattainment in, or interfere
with maintenance by, any other state with respect to that NAAQS. As
described further in Section III.C.2, the EPA has developed several
regional rulemakings to address the requirements of CAA section
110(a)(2)(D)(i)(I) for the various ozone NAAQS. The EPA's most recent
rulemaking, Determination Regarding Good Neighbor Obligations for the
2008 Ozone National Ambient Air Quality Standard (the Determination
Rule), finalized a determination that the existing Cross-State Air
Pollution Rule Update for the 2008 Ozone NAAQS (CSAPR Update) \17\
fully addresses

certain states' interstate transport obligations under CAA section
110(a)(2)(D)(i)(I) for the 2008 ozone NAAQS. 83 FR 65878 (December 21,
2018).
---------------------------------------------------------------------------

    \17\ See Cross-State Air Pollution Rule Update for the 2008
Ozone National Ambient Air Quality Standards, Final Rule, 81 FR
74504 (October 26, 2016).
---------------------------------------------------------------------------

    Section 110(a)(2)(D)(ii) of the CAA further requires SIPs to
contain adequate provisions insuring compliance with the applicable
requirements of, inter alia, CAA section 126. Thus, where the EPA has
made a finding pursuant to CAA section 126(b), this provision requires
states to revise their SIPs to adopt any emissions limitations and
compliance schedules provided by the EPA under CAA section 126(c).

C. The EPA's Historical Approach To Addressing Interstate Transport of
Ozone Under the Good Neighbor Provision

    Given that formation, atmospheric residence, and transport of ozone
can occur on a regional scale (i.e., across hundreds of miles) and that
many separate areas across the eastern U.S. have struggled to attain
and maintain the NAAQS, the states and the EPA have historically
addressed the interstate transport of ozone pursuant to the good
neighbor provision by promulgating rulemakings that employ regional
trading programs to reduce NOX emissions. Each of these
rulemakings followed a similar four-step interstate transport framework
to evaluate the extent of the ozone transport problem (i.e., the
breadth of downwind ozone problems and the contributions from upwind
states) and, ultimately, to find that downwind states' problems
attaining and maintaining the ozone NAAQS result from an interconnected
system of transported pollution emitted by multiple upwind sources
located in different upwind states combined with downwind (i.e.,
locally generated) ozone.
1. Description of the Four-Step Interstate Transport Framework
    Through the development and implementation of several previous
rulemakings,\18\ the EPA, working in partnership with states,
established the following four-step interstate transport framework to
address the requirements of the good neighbor provision for regional
pollutants such as ozone and fine particulate matter
(PM2.5):
---------------------------------------------------------------------------

    \18\ See Finding of Significant Contribution and Rulemaking for
Certain States in the Ozone Transport Assessment Group Region for
Purposes of Reducing Regional Transport of Ozone (also known as the
NOX SIP Call), 63 FR 57356 (October 27, 1998); Clean Air
Interstate Rule (CAIR) Final Rule, 70 FR 25162 (May 12, 2005); CSAPR
Final Rule, 76 FR 48208 (August 8, 2011); CSAPR Update Final Rule,
81 FR 74504 (October 26, 2016); Determination Rule, 83 FR 65878
(December 21, 2018).
---------------------------------------------------------------------------

    (1) Identify downwind receptors that are expected to have problems
attaining or maintaining the NAAQS. The EPA historically identified
downwind areas with air quality problems, or receptors, using air
quality modeling projections for a future analytic year and, where
appropriate, considering monitored air quality data.
    (2) Determine which upwind states are linked to these identified
downwind air quality problems and thus warrant further analysis to
determine whether their emissions violate the good neighbor provision.
In the EPA's most recent transport rulemakings for the 1997 and 2008
ozone NAAQS, as well as the 1997 and 2006 PM2.5 NAAQS, the
Agency identified such upwind states to be those modeled to contribute
at or above a threshold relative to the applicable NAAQS.
    (3) For states linked to downwind air quality problems, identify
upwind emissions (if any) on a statewide basis that will significantly
contribute to nonattainment or interfere with maintenance of a standard
at a receptor in another state. In the EPA's prior rulemakings for
ozone and PM2.5, the Agency identified and apportioned
emissions reduction responsibility among multiple upwind states linked
to downwind air quality problems by identifying a uniform level of
control stringency based on cost and air quality factors evaluated in a
multi-factor test.
    (4) For upwind states that are found to have emissions that will
significantly contribute to nonattainment or interfere with maintenance
of the NAAQS downwind, implement the necessary emissions reductions
within the state. When the EPA has promulgated federal implementation
plans (FIPs) addressing the good neighbor provision for ozone and
PM2.5 NAAQS in prior transport rulemakings, the EPA has
typically required affected sources in upwind states to participate in
allowance trading programs to achieve the necessary emissions
reductions.\19\ In addition, the EPA has also offered states the
opportunity to participate in comparable EPA-operated allowance trading
programs to achieve the necessary emissions reductions through SIPs.
---------------------------------------------------------------------------

    \19\ While the EPA has chosen to implement emissions reductions
through allowance trading programs for states found to have a
downwind impact, upwind states can choose to submit a SIP that
implements such reductions through other enforceable mechanisms that
meet the requirements of the good neighbor provision, such as the
enforceable mechanisms that the petitioner apparently favors and
argues for in its petition.
---------------------------------------------------------------------------

    Using the four-step framework to evaluate a particular interstate
transport problem allows the EPA to determine whether upwind sources
are actually linked to a downwind air quality problem, whether and
which sources can be cost-effectively controlled to address that
downwind air quality problem, what level of emissions should be
eliminated to address the downwind air quality problem, and the means
of implementing corresponding emissions limits (i.e., source-specific
rates, or statewide emissions budgets in a limited regional allowance
trading program). The outcome of this assessment varies based on the
scope of the air quality problem, the availability and cost of controls
at sources in upwind states, and the estimated impact of upwind
emissions reductions on downwind ozone concentrations.
2. Prior Regional Rulemakings Under the Good Neighbor Provision
    The EPA's first regional interstate transport rulemaking, the
NOX SIP Call, addressed the 1979 ozone NAAQS. 63 FR 57356
(October 27, 1998).\20\ The NOX SIP Call was the result of
the analytic work and recommendations of the Ozone Transport Assessment
Group, which was organized and led by states in consultation with the
EPA and other stakeholders. The EPA used this collaboratively-developed
analysis to conclude in the NOX SIP Call that ``[t]he fact
that virtually every nonattainment problem is caused by numerous
sources over a wide geographic area is a factor suggesting that the
solution to the problem is the implementation over a wide area of
controls on many sources, each of which may have a small or
unmeasurable ambient impact by itself.'' 63 FR 57356, 57377 (October
27, 1998). The NOX SIP Call promulgated statewide emissions
budgets and required upwind states to adopt SIPs that would decrease
their NOX emissions to meet these budgets, thereby
prohibiting the emissions that significantly contribute to
nonattainment or interfere with maintenance of the ozone NAAQS in
downwind states. The EPA also promulgated a model rule for a regional
allowance trading program called the

NOX Budget Trading Program that states could adopt in their
SIPs as a mechanism to achieve some or all required emissions
reductions. All jurisdictions covered by the NOX SIP Call
ultimately chose to adopt the NOX Budget Trading Program
into their SIPs. The NOX SIP Call was ultimately upheld by
the U.S. Court of Appeals for the District of Columbia Circuit (D.C.
Circuit) in all pertinent respects. See Michigan v. EPA, 213 F.3d 663
(2000).
---------------------------------------------------------------------------

    \20\ As originally promulgated, the NOX SIP Call also
addressed good neighbor obligations under the 1997 8-hour ozone
NAAQS, but the EPA subsequently stayed the rule's provisions with
respect to that standard. 40 CFR 51.121(q). The EPA recently
finalized an action rescinding the 1997 ozone NAAQS as a basis for
the NOX SIP Call. 84 FR 8422 (March 8, 2019).
---------------------------------------------------------------------------

    In coordination with the NOX SIP Call rulemaking under
CAA section 110(a)(2)(D)(i)(I), the EPA also addressed several pending
CAA section 126(b) petitions submitted by eight northeastern states
regarding the same air quality issues addressed by the NOX
SIP Call, specifically interstate ozone transport for the 1979 ozone
NAAQS. These CAA section 126(b) petitions asked the EPA to find that
ozone emissions from numerous sources located in 30 states and the
District of Columbia had adverse air quality impacts on the petitioning
downwind states. Half of the petitioning states (i.e., Connecticut,
Maine, New York, and Pennsylvania) requested an allowance trading
program to reduce NOX emissions and remedy regional
interstate ozone transport. 63 FR 56297 (October 21, 1998). Based on
analysis conducted for the NOX SIP Call regarding upwind
state impacts on downwind air quality, the EPA, in May 1999, made
technical determinations regarding the claims in the petitions, but did
not at that time make the CAA section 126(b) findings requested by the
petitions. 64 FR 28250 (May 25, 1999). In making these technical
determinations, the EPA concluded that the NOX SIP Call
would fully address and remediate the claims raised in these petitions
and that the EPA would, therefore, not need to take separate action to
remedy any potential violations of the CAA section 110(a)(2)(D)(i)
prohibition. 64 FR 28252. However, subsequent litigation over the
NOX SIP Call led the EPA to ``de-link'' the CAA section
126(b) petition response from the NOX SIP Call, and the EPA
made final CAA section 126(b) findings for 12 states named in the
petitions and the District of Columbia. The EPA found that sources in
these states emitted in violation of the prohibition in the good
neighbor provision with respect to the 1979 ozone NAAQS based on the
affirmative technical determinations made in the May 1999 rulemaking.
To remedy the violation under CAA section 126(c), the EPA required
affected sources in the upwind states to participate in a regional
allowance trading program whose requirements were designed to be
interchangeable with the requirements of the optional NOX
Budget Trading Program model rule provided under the NOX SIP
Call. 65 FR 2674 (January 18, 2000). The EPA's action on these CAA
section 126(b) petitions was upheld by the D.C. Circuit. See
Appalachian Power Co. v. EPA, 249 F.3d 1032 (D.C. Cir. 2001).
    The EPA next promulgated the Clean Air Interstate Rule (CAIR), 70
FR 25162 (May 12, 2005), to address interstate transport under the good
neighbor provision with respect to the 1997 ozone NAAQS, as well as the
1997 PM2.5 NAAQS. 70 FR 25172. The EPA adopted the same
approach for quantifying the level of states' significant contribution
to downwind nonattainment in CAIR as it used in the NOX SIP
Call, based on the determination in the NOX SIP Call that
downwind ozone nonattainment is due to the impact of emissions from
numerous upwind sources and states. 70 FR 25162, 25172 (May 12, 2005).
The EPA explained that ``[t]ypically, two or more States contribute
transported pollution to a single downwind area, so that the
`collective contribution' is much larger than the contribution of any
single State.'' 70 FR 25186. CAIR included two distinct regulatory
processes: (1) A rulemaking to define significant contribution (i.e.,
the emissions reduction obligation) under the good neighbor provision
and provide for submission of SIPs eliminating that contribution, 70 FR
25162 (May 12, 2005); and (2) a rulemaking to promulgate, where
necessary, FIPs imposing emissions limitations in the event states did
not submit SIPs. 71 FR 25328 (April 28, 2006). The FIPs required EGUs
in affected states to participate in regional allowance trading
programs, which replaced the previous NOX Budget Trading
Program.
    In conjunction with the second CAIR rulemaking, which promulgated
backstop FIPs, the EPA acted on a CAA section 126(b) petition received
from the state of North Carolina on March 19, 2004, seeking a finding
that large EGUs located in 13 states were significantly contributing to
nonattainment and/or interfering with maintenance of the 1997 ozone
NAAQS and the 1997 PM2.5 NAAQS in North Carolina. Citing the
analyses conducted to support the promulgation of CAIR, the EPA denied
North Carolina's CAA section 126(b) petition in full based on
determinations either that the named states were not adversely
impacting downwind air quality in violation of the good neighbor
provision, or that such impacts were fully remedied by implementation
of the emissions reductions required by the CAIR FIPs. 71 FR 25328,
25330 (April 28, 2006).
    The D.C. Circuit found that the EPA's approach to CAA section
110(a)(2)(D)(i)(I) in CAIR was ``fundamentally flawed'' in several
respects, and the rule was remanded in July 2008 with the instruction
that the EPA replace the rule ``from the ground up.'' North Carolina,
531 F.3d at 929. The decision concluded the EPA's analysis and
compliance mechanisms did not address all elements required by the
statute. The EPA's separate action denying North Carolina's CAA section
126(b) petition was not challenged.
    On August 8, 2011, the EPA promulgated CSAPR to replace CAIR. 76 FR
48208 (August 8, 2011). CSAPR addressed the same (1997) ozone and
PM2.5 NAAQS as CAIR and additionally addressed interstate
transport for the 2006 PM2.5 NAAQS by requiring 28 states to
reduce sulfur dioxide (SO2) emissions, annual NOX
emissions, and/or ozone season NOX emissions that would
significantly contribute to other states' nonattainment or interfere
with other states' ability to maintain these air quality standards.
Consistent with prior determinations made in the NOX SIP
Call and CAIR, the EPA again found that multiple upwind states
contributed to ozone nonattainment in multiple downwind states.
Specifically, the EPA found ``that the total `collective contribution'
from upwind sources represents a large portion of PM2.5 and
ozone at downwind locations and that the total amount of transport is
composed of the individual contribution from numerous upwind states.''
76 FR 48237. Accordingly, the EPA conducted a regional analysis,
calculated emissions budgets for affected states, and required EGUs in
these states to participate in new regional allowance trading programs
to reduce statewide emissions levels.\21\ CSAPR was subject to nearly 4
years of litigation. Ultimately, the Supreme Court upheld the EPA's
approach to calculating emissions reduction obligations and
apportioning upwind state responsibility under the good neighbor
provision, but also held that the EPA was precluded from requiring more
emissions reductions

than necessary to address downwind air quality problems, or ``over-
controlling'' upwind state emissions. See EPA v. EME Homer City
Generation, L.P., 134 S. Ct. 1584, 1607-09 (2014) (EME Homer City).\22\
---------------------------------------------------------------------------

    \21\ The CSAPR trading programs included assurance provisions to
ensure that emissions are reduced within each individual state, in
accordance with North Carolina, 531 F.3d at 907-08 (holding the EPA
must require elimination of emissions from each upwind state that
contribute significantly to nonattainment and interfere with
maintenance in downwind areas). Those provisions were also included
in the CSAPR Update and took effect with the 2017 CSAPR compliance
periods.
    \22\ On remand from the Supreme Court, the D.C. Circuit further
affirmed various aspects of the CSAPR, while remanding the rule
without vacatur for reconsideration of certain states' emissions
budgets where it found those budgets may over-control emissions
beyond what was necessary to address the good neighbor requirements.
EME Homer City Generation, L.P. v. EPA, 795 F.3d 118 (2015) (EME
Homer City II). The EPA addressed the remand in several rulemaking
actions in 2016 and 2017.
---------------------------------------------------------------------------

    In 2016, the EPA promulgated the CSAPR Update to address the good
neighbor provision requirements for the 2008 ozone NAAQS. 81 FR 74504
(October 26, 2016). The CSAPR Update built upon previous regulatory
efforts to address the collective contributions of ozone pollution from
22 states in the eastern U.S. to widespread downwind air quality
problems. As with previous rulemakings, the EPA evaluated the nature
(i.e., breadth and interconnectedness) of the ozone problem and
NOX reduction potential from EGUs, including essentially all
the EGUs at the facilities named in the New York CAA section 126(b)
petition.\23\ In the CSAPR Update, the EPA quantified emissions
reduction obligations for each state based on an analysis of control
strategies that could be implemented by the 2017 ozone season and
implemented those emissions reductions through FIPs which required EGUs
in affected states to participate in a regional allowance trading
program to further reduce statewide NOX emissions levels.
---------------------------------------------------------------------------

    \23\ The EPA uses the language ``essentially all the EGUs at the
facilities named . . .'' (emphasis added) to clarify that the New
York petition identifies sources at the facility, rather than at the
unit, level. The CSAPR Update looked at unit-level data and included
all fossil-fuel-fired boiler or combustion turbine EGUs with a
capacity (electrical output) greater than 25 megawatts (MW). See 81
FR 74563 (October 26, 2016).
---------------------------------------------------------------------------

    At the time the EPA finalized the CSAPR Update in 2016, the EPA was
unable to determine whether the rule fully resolved good neighbor
obligations with respect to the 2008 ozone NAAQS for most (i.e., 21) of
the states subject to that action, including those addressed in New
York's petition (i.e., Illinois, Indiana, Kentucky, Maryland, Michigan,
Ohio, Pennsylvania, Virginia and West Virginia). The EPA stated that,
based on its analysis at that time, the emissions reductions required
by the rule ``may not be all that is needed'' to address transported
emissions.\24\ 81 FR 74521-22 (October 26, 2016). The information
available at that time suggested that downwind air quality problems
would remain in 2017 after implementation of the CSAPR Update and that
upwind states continued to be linked to those downwind problems at or
above the one-percent threshold. However, in the CSAPR Update, the EPA
could not determine whether, in step 3 of the four-step interstate
transport framework, the EPA had quantified all emissions reductions
that may be considered cost-effective because the rule did not evaluate
non-EGU ozone season NOX reductions and further EGU control
strategies (i.e., the implementation of new post-combustion controls)
that were achievable on timeframes extending beyond the 2017 analytic
year.
---------------------------------------------------------------------------

    \24\ The EPA determined that the emissions reductions required
by the CSAPR Update satisfied the full scope of the good neighbor
obligation for Tennessee with respect to the 2008 ozone NAAQS. 81 FR
74551-52 (October 26, 2016).
---------------------------------------------------------------------------

    On December 6, 2018, the EPA finalized a determination that, based
on the latest available emissions inventory and air quality modeling
data for a 2023 analytic year, the CSAPR Update fully addresses the
good neighbor provision requirements for the 2008 ozone NAAQS for 20
eastern states (among the 22) previously addressed in the CSAPR Update.
83 FR 65878 (December 21, 2018). The EPA's Determination Rule applied
the four-step interstate transport framework but did not move beyond an
analysis at step 1 of the four-step framework, because the EPA found
that there would be no remaining nonattainment or maintenance receptors
for the 2008 ozone NAAQS in the eastern U.S. in 2023. Therefore, with
the CSAPR Update fully implemented, the EPA finalized in the
Determination Rule a finding that the 20 states addressed by that
action (including eight of the nine states named in New York's
petition) will not contribute significantly to nonattainment in, or
interfere with maintenance by, any other state regarding the 2008 ozone
NAAQS. The EPA had already determined that the remaining two states
would have no remaining good neighbor obligation for the 2008 ozone
NAAQS--one in the CSAPR Update (Tennessee), 81 FR 74540 (October 26,
2016), and the other in a separate SIP approval (Kentucky, the ninth
state named in New York's petition), 83 FR 33730 (July 17, 2018).
    Most recently, the EPA acted on five CAA section 126(b) petitions
submitted by the states of Delaware and Maryland regarding various
sources in five upwind states with regard to the 2008 and 2015 ozone
NAAQS. In denying the petitions, the EPA applied the same four-step
interstate transport framework used in prior rulemakings and relied on
analysis and determinations made in the CSAPR Update for purposes of
evaluating the good neighbor obligations with respect to the 2008 ozone
NAAQS. 83 FR 50444 (October 5, 2018).

D. The CAA Section 126(b) Petition From New York

    On March 12, 2018, the New York State Department of Environmental
Conservation (NY DEC) submitted a CAA section 126(b) petition alleging
that emissions from a group of specified upwind sources in Illinois,
Indiana, Kentucky, Maryland, Michigan, Ohio, Pennsylvania, Virginia,
and West Virginia significantly contribute to nonattainment and
interfere with maintenance of the 2008 and 2015 ozone NAAQS in New York
State, specifically in the New York-Northern New Jersey-Long Island,
NY-NJ-CT area (hereafter the New York metropolitan area or NYMA) and in
Chautauqua County in western New York.
    1. The petition asserts that Chautauqua County and the NYMA have an
air quality problem for the 2008 and the 2015 ozone NAAQS.
    The petition explains that the EPA designated the Chautauqua County
area (i.e., Jamestown, New York) as Marginal nonattainment for the 2008
ozone NAAQS and that the area attained the NAAQS by the Marginal area
attainment date of July 20, 2015. The petition asserts, however, that
the area remains in danger of exceeding the ozone NAAQS, particularly
the 2015 standard.
    The petition also explains that the EPA designated the NYMA as
Marginal nonattainment for the 2008 ozone NAAQS. The NYMA failed to
attain the NAAQS by the Marginal attainment deadline of July 20, 2015,
and the EPA subsequently reclassified the area to a Moderate
nonattainment area on June 3, 2016.\25\ The petition further asserts
that all three states in the NYMA (i.e., New York, New Jersey and
Connecticut) have surpassed their three-percent-per-year emissions
reductions requirements for the 2008 NAAQS; yet certified monitoring
data through 2016 and (at the time of the petition submittal)
preliminary 2017 data indicate that the area is not attaining the 2008
NAAQS, with one monitor in Connecticut recording a preliminary 2017
design value of 83 ppb. The petition, thus, concludes that the area
will likely be designated nonattainment for the 2015 ozone NAAQS.\26\
---------------------------------------------------------------------------

    \25\ The EPA notes that New York submitted its CAA section
126(b) petition before the EPA proposed to reclassify the NYMA as a
Serious nonattainment area. 83 FR 56781 (November 14, 2018).
    \26\ The petition asserts that the EPA had not yet issued final
designations at the time the petition was submitted. On April 30,
2018, the EPA designated New York-Northern New Jersey-Long Island,
NY-NJ-CT area as a Moderate nonattainment area, the same as the NYMA
nonattainment area for 2008 ozone NAAQS. 83 FR 25776 (June 4, 2018).

---------------------------------------------------------------------------

    2. The petition asserts that NOX transport from the nine
named states impacts air quality in New York State.
    The petition identifies nine states that were linked to air quality
problems in New York in the EPA's 2017 contribution modeling in the
CSAPR Update based on impacts equal to or greater than the threshold of
one percent of the 2008 NAAQS (or 0.75 ppb or more): Illinois, Indiana,
Kentucky, Maryland, Michigan, Ohio, Pennsylvania, Virginia and West
Virginia. The petition also asserts that the high concentrations of
ozone that are transported to New York are largely the result of
emissions from major stationary sources of NOX located in
the linked states. The petition cites efforts by New York and other
parties to mitigate regional transport of NOX, including
implementation of the NOX Budget Trading Program under the
NOX SIP Call and the CSAPR allowance trading programs.
    Additionally, the petition describes a study that allegedly found
that air transported into Chautauqua County on the worst air quality
days results in maximum daily ozone concentrations that, on average,
are within 2 ppb of the 2015 ozone NAAQS and often exceed the standard
of 70 ppb.\27\ The petition concludes that, given the absence of major
sources in the Chautauqua County area, reductions in ozone precursor
emissions are needed from upwind states, especially from sources in
Illinois, Indiana, Kentucky, Michigan, Ohio, and Virginia.
---------------------------------------------------------------------------

    \27\ The petition discusses the results of a study titled the
``Dunkirk Monitor Transport Study,'' which presents an analysis of
back-trajectories used to single out interstate airflow on ``design
days,'' which the petition defines as days considered in the
calculation of the design values. The subject days include the four
days in each year from 2013 to 2017 with the largest daily maximum
8-hour ozone concentrations at the Dunkirk monitoring site in
Chautauqua County, New York. The Dunkirk monitoring site is the
design value monitoring site in Chautauqua County (i.e., the site
with the highest design value in the county).
---------------------------------------------------------------------------

    3. The petition asserts that facilities emitting (or projected to
emit) above 400 tons of NOX significantly contribute to air
quality problems or interfere with maintenance in New York State.
    When analyzing significant ozone contributions, the petition
considers the highest emitting facilities from the previously named
linked states. Specifically, the petition identifies EGU and non-EGU
facilities emitting, or projected to emit, 400 tons per year or more of
NOX in each of these linked states and asserts that these
facilities are expected to have the greatest impact on the ability of
the NYMA and Chautauqua County to attain and maintain the 2008 and 2015
NAAQS.\28\ The petition asserts that the identified facilities can
reasonably be retrofitted with control equipment or can operate
existing controls more frequently to reduce NOX.
---------------------------------------------------------------------------

    \28\ The petition identifies which facilities emit 400 tons per
year of more of NOX based on 2017 EGU projections by the
Mid-Atlantic Regional Air Management Association (MARAMA). The
petition also identifies non-EGU sources emitting greater than 400
tons of NOX in the 2014 National Emissions Inventory
(NEI).
---------------------------------------------------------------------------

    The petition provides and uses NY DEC generated air quality
modeling data to quantify projected 2017 impacts on ozone
concentrations from the collective NOX emissions of the EGU
and non-EGU (including oil and gas) facilities that emitted at least
400 tons-per-year of NOX in each state that was linked in
the EPA's modeling for the CSAPR Update (``400 tons-per-year
sources''). According to the petition, results from NY DEC's
independent modeling analysis show single-day impacts from individual
states' groups of 400 tons-per-year sources of up to 6.34 ppb in
Chautauqua County and 4.97 ppb in the New York portion of the NYMA
nonattainment area.\29\
---------------------------------------------------------------------------

    \29\ The petition provides additional detail regarding the
modeling methodology. Specifically, the petition notes that NY DEC
used version 5.0.2 of the Community Multiscale Air Quality (CMAQ)
model with the EPA's Weather Research Forecast (WRF) 2011
meteorological data to model hourly ozone concentrations during the
period May 18 to July 30 for a 2017 ``baseline'' scenario and
additional state-by-state ``control'' modeling scenarios in which
emissions from the named sources in a given state were set to zero.
The petition explains that NY DEC then used the modeled
concentrations to calculate the 8-hour daily maximum average (MDA8)
in each grid cell on each day of the modeling period for each
modeled scenario. The difference in MDA8 concentrations between the
2017 baseline and each state zero-out run was used to represent the
contributions on each day. The NY DEC then selected the largest
single-day contribution from among the highest ozone concentration
days to support their analysis of contributions relative to a one-
percent-of-the-NAAQS threshold.
---------------------------------------------------------------------------

    The petition asserts that, where the maximum influence from an
individual state's combined 400 tons-per-year sources exceeds 0.75 ppb
at a particular monitor, this indicates significant contribution to
nonattainment or interference with maintenance of the 2008 ozone NAAQS,
and an influence above 0.70 ppb indicates significant contribution to
nonattainment or interference with maintenance of the 2015 ozone NAAQS.
    The petition also challenges the applicability of the EPA's
recently-released 2023 air quality modeling \30\ to this CAA section
126(b) petition. The petition states that NY DEC has significant
concerns about the assumptions and results of the EPA's modeling, such
as the EPA's expectation that uncontrolled EGUs will greatly reduce
their emissions rates in the absence of unit-level enforceable limits
and the concern that the EPA may have underestimated the ozone
concentration results for monitoring sites located near significant
water bodies based on the treatment of model cells containing a land/
water interface. The petition also asserts that modeling of 2023 is
insufficient to support good neighbor SIPs and cannot be used to
support a review of New York's petition because CAA section 126(c)
explicitly states that compliance must be met ``in no case later than
three years after the date of [a CAA section 126(b)] finding,'' and
2023 is more than 3 years after the deadline by which the EPA must act
on the NY DEC petition. The EPA notes that New York submitted its CAA
section 126(b) petition before the EPA finalized the Determination
Rule.
---------------------------------------------------------------------------

    \30\ See the EPA's October 27, 2017 memorandum titled,
``Supplemental Information on the Interstate Transport State
Implementation Plan Submissions for the 2008 Ozone National Ambient
Air Quality Standards under Clean Air Act Section
110(a)(2)(D)(i)(I)'' that provided future year ozone design values
for monitoring sites in the U.S. based on updated air quality
modeling (for 2023) and monitoring data.
---------------------------------------------------------------------------

    4. The petition requests that the EPA establish enforceable
emissions limitations for the named major NOX sources at
levels designed to prevent them from significantly contributing to
nonattainment or interfering with maintenance in New York State.
    The petition requests that the EPA establish permanent and
enforceable NOX emissions limits based on New York's
determination of available cost-effective controls. Specifically, the
petition requests that the named sources be subject to emissions limits
consistent with Reasonably Available Control Technology (RACT) as
defined by New York State, which bases its presumptive limits and
facility-specific control analyses on a standard of $5,000 per ton of
NOX reduced.\31\ The petition acknowledges that some of the
facilities identified in the petition may already

operate with a NOX emissions rate similar to New York's RACT
limits. Nonetheless, the petition asks that the EPA establish
enforceable daily emissions limits during the ozone season to require
these sources to continue to operate at these rates in the future. The
petition claims that enforceable emissions limits would prevent
emissions controls from being turned off, which the petition asserts
occurs when the sources in the state are collectively emitting well-
below their seasonal CSAPR budgets.
---------------------------------------------------------------------------

    \31\ According to the petition, New York's standard of $5,000
per ton of NOX reduced for RACT is inflation-adjusted.
Hence, the EPA observes that this cost per ton will not change in
future years even if inflation leads to increases in NOX
control costs per ton of NOX reduced beyond current
estimates. For example, assuming a control cost of $5,000 per ton of
NOX reduced, a 10 percent inflation rate will yield a
control cost of $5,500 per ton (1.10 * 5,000), but the inflation-
adjusted RACT basis of $5,000 per ton of NOX reduced
remains unchanged.
---------------------------------------------------------------------------

    5. Subsequent actions and correspondence regarding the New York
petition.
    Consistent with CAA section 307(d)(10), the EPA determined that the
60-day period for responding to New York's petition was insufficient
for the EPA to complete the necessary technical review, develop an
adequate proposal, and allow time for notice and comment, including an
opportunity for public hearing, on a proposed finding regarding whether
emissions from the group of identified sources in nine states
(Illinois, Indiana, Kentucky, Maryland, Michigan, Ohio, Pennsylvania,
Virginia and West Virginia) significantly contribute to nonattainment
and interfere with maintenance of the 2008 and 2015 ozone NAAQS in New
York State. On May 11, 2018, the EPA published a final rule extending
the deadline for acting on New York's section 126(b) petition to
November 9, 2018.\32\
---------------------------------------------------------------------------

    \32\ 83 FR 21909 (May 11, 2018).
---------------------------------------------------------------------------

    Since receiving New York's section 126(b) petition on March 14,
2018, the EPA has received several letters from the public providing
information regarding the content of the subject petition. We briefly
describe those letters here.
    On April 13, 2018, the U.S. Chamber of Commerce submitted a letter
to the EPA requesting an extension beyond the 60-day statutory deadline
for petition response and claiming legal and technical deficiencies in
the New York petition. Specifically, the U.S. Chamber of Commerce
asserts that the petition over-estimates emissions from ``numerous''
facilities identified in the petition and inappropriately includes
monitoring sites that currently attain the ozone NAAQS. Further the
U.S. Chamber of Commerce contends that applying New York's definition
of RACT outside of New York raises ``significant constitutional and
statutory issues.''
    On June 20, 2018, Sunoco Partners Marketing & Terminals submitted a
letter to the EPA providing corrections to the operating status of the
Marcus Hook Refinery, identified in the New York section 126(b)
petition as the Sunoco Inc. (R&M)/Marcus Hook Refinery, and requesting
that the EPA remove the identified source from the list of facilities
emitting more than 400 tons per year of NOX.
    On April 25, 2018, the Air Stewardship Coalition (ASC) submitted a
letter to the EPA requesting an extension beyond the 60-day statutory
deadline for petition response citing the technical complexity of the
New York petition. ASC submitted a follow-up letter on September 24,
2018, asking the EPA to deny New York's section 126(b) petition. The
ASC letter asserts that New York State has no ozone attainment issues
outside of the NYMA and that the NY DEC's independent modeling used a
``non-standard approach'' that resulted in ``flawed'' results.
    On May 31, 2018, the Midwest Ozone Group (MOG) submitted a letter
asking the EPA to deny New York's section 126(b) petition. The MOG
letter asserts that the New York petition is deficient in that it
incorrectly characterizes the emissions from identified sources and
states; the petition does not consider exceptional events or
international transport; and the petition does not consider the EPA's
most recent modeling showing that all New York monitoring sites will
attain the 2008 ozone NAAQS. Further, MOG provides the results of its
own independent modeling of the May 1 through August 31, 2011, ozone
season run at a 4-kilometer (km) grid resolution rather than the 12 km
grid resolution used in the EPA's modeling. MOG asserts that at the
finer resolution, all monitoring sites in New York attain both the 2008
and the 2015 ozone NAAQS. MOG provided the EPA with supplemental
comments and analyses on October 19, 2018, and on December 17, 2018.
MOG asserts that its additional comments further support the EPA's
denial of the New York section 126(b) petition.
    The EPA acknowledges receipt of these letters and has made them
available in the docket for this action. However, the EPA is not
responding directly to these letters in this notice nor is the EPA
relying on the information provided in these letters as a basis for its
proposed action. Rather, the EPA encourages interested parties to
review this proposal and then submit relevant comments during the
public comment period.

IV. The EPA's Proposed Decision on the CAA Section 126(b) Petition From
New York

A. The EPA's Approach for Granting or Denying CAA Section 126(b)
Petitions Regarding the 2008 and 2015 8-Hour Ozone NAAQS

    As discussed in Section III.B of this notice, section 126(b) of the
CAA provides a mechanism for states and other political subdivisions to
seek abatement of pollution in other states that may be affecting their
air quality. Section 126(b) does not, however, identify a specific
methodology or specific criteria for the Administrator to apply when
making a CAA section 126(b) finding or denying a petition. Therefore,
the EPA has the discretion to identify relevant criteria and develop a
reasonable methodology for making a CAA section 126(b) finding. See,
e.g., Chevron, U.S.A., Inc. v. NRDC, 467 U.S. 837, 842-43 (1984);
Smiley v. Citibank, 517 U.S. 735, 744-45 (1996).
    With respect to the statutory requirements of section 126 and
section 110(a)(2)(D)(i) of the CAA, the EPA has consistently
acknowledged that Congress created these provisions as two independent
statutory tools to address the problem of interstate pollution
transport. See, e.g., 76 FR 69052, 69054 (November 7, 2011).\33\ The
fact that Congress did not indicate any preference for one over the
other, suggests that either tool could serve as a legitimate means to
produce the desired result. While the provisions in CAA section
110(a)(2)(D)(i) and section 126 are independent, they are also closely
linked. A violation of the prohibition in CAA section 110(a)(2)(D)(i)
is a condition precedent for action under CAA section 126(b) and,
critically, both provisions construe significant contribution to
nonattainment and interference with maintenance identically (since the
identical terms are naturally interpreted as meaning the same thing in
the two linked provisions). See Appalachian Power, 249 F. 3d at 1049-
50.
---------------------------------------------------------------------------

    \33\ Courts have also upheld the EPA's position that CAA
sections 110(a)(2)(D)(i) and section 126 are two independent
statutory tools to address the same problem of interstate transport.
See GenOn REMA, LLC v. EPA, 722 F.3d 513, 520-23 (3d Cir. 2013);
Appalachian Power, 249 F.3d at 1047.
---------------------------------------------------------------------------

    Thus, in addressing a CAA section 126(b) petition for ozone
transport, the EPA believes it is appropriate to interpret these
ambiguous terms (i.e., ``contribute significantly to nonattainment''
and ``interfere with maintenance'') consistent with the EPA's past
approach to evaluating interstate ozone pollution transport

under the good neighbor provision, and its interpretation and
application of that related provision of the statute. As described
further in Section III of this notice, ozone is a regional air
pollutant and the EPA's previous analyses and regulatory actions have
evaluated the regional interstate ozone transport problem using a four-
step analytic framework. The EPA most recently applied this four-step
framework in promulgating the CSAPR Update and the Determination Rule
to address interstate transport with respect to the 2008 ozone NAAQS
under CAA section 110(a)(2)(D)(i)(I). This approach is particularly
applicable with respect to New York's claims regarding the 2008 ozone
NAAQS because both rulemakings address projected air quality problems
in New York and the impacts of upwind states, including those named in
the petition, on such areas. Given the specific cross-reference in CAA
section 126(b) to the substantive prohibition in CAA section
110(a)(2)(D)(i), the EPA believes any prior findings made under the
good neighbor provision are informative--if not determinative--for a
CAA section 126(b) action. Therefore, in this instance, the EPA's
decision whether to grant or deny the CAA section 126(b) petition
regarding the 2008 8-hour ozone NAAQS depends on application of the
four-step interstate transport framework.
    While the EPA previously applied the four-step interstate transport
framework and interpreted significant contribution and interference
with maintenance under CAA section 110(a)(2)(D)(i) for the 2008 ozone
NAAQS via the CSAPR Update and the Determination Rule, the EPA has not
yet engaged in a rulemaking action to apply the good neighbor provision
for the 2015 ozone NAAQS. However, the EPA recently released technical
information intended to inform states' development of SIPs to address
the 2015 ozone standard.\34\ This information included the results of
air quality modeling to identify potential downwind air quality
problems in 2023, which we discuss in more detail in Section IV.B.1 of
this document. As part of the memorandum releasing the technical
information, the EPA acknowledged that states have the flexibility to
pursue approaches that may differ from the EPA's historical approach to
evaluating interstate transport in developing their good neighbor
SIPs.\35\ Nonetheless, the EPA's technical analysis and the potential
flexibilities identified in the memorandum generally followed the basic
elements of the EPA's historical four-step interstate transport
framework. As described previously, CAA section 126(b) does not
identify a specific methodology or specific criteria for the
Administrator to apply when making a CAA section 126(b) finding or
denying a petition. Thus, given the EPA's discretion to identify
relevant criteria and develop a reasonable methodology to inform a CAA
section 126(b) finding, the EPA believes that it continues to be
appropriate for the Agency to evaluate the claims regarding the 2015
ozone NAAQS in New York's section 126(b) petition consistent with the
EPA's four-step interstate transport framework used to evaluate other
ozone NAAQS.
---------------------------------------------------------------------------

    \34\ See Information on the Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards under Clean Air Act Section 110(a)(2)(D)(i)(I)
(March 27, 2018).
    \35\ The EPA has also released two additional memoranda
providing guidance to states developing good neighbor SIPs for the
2015 ozone NAAQS. See Analysis of Contribution Thresholds for Use in
Clean Air Act Section 110(a)(2)(D)(i)(I) Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards (August 31, 2018); and Considerations for
Identifying Maintenance Receptors for Use in Clean Air Act Section
110(a)(2)(D)(i)(I) Interstate Transport State Implementation Plan
Submissions for the 2015 Ozone National Ambient Air Quality
Standards (October 19, 2018). All three memoranda are available in
the docket for this proposed action and at https://www.epa.gov/airmarkets/memo-and-supplemental-information-regarding-interstate-transport-sips-2015-ozone-naaqs.
---------------------------------------------------------------------------

    Accordingly, because the EPA interprets ``contribute significantly
to nonattainment'' and ``interfere with maintenance'' to mean the same
thing under both sections 110(a)(2)(D)(i) and 126(b), the EPA's
decision whether to grant or deny a CAA section 126(b) petition
regarding both the 2008 and 2015 ozone NAAQS depends on application of
the analysis used to address CAA section 110(a)(2)(D). That is, the EPA
assesses whether there is a downwind air quality problem in the
petitioning state (i.e., step 1 of the four-step interstate transport
framework); whether the upwind state where the source subject to the
petition is located is linked to the downwind air quality problem
(i.e., step 2); and, if such a linkage exists, whether there are cost-
effective emissions reductions available from sources in the upwind
state to support a conclusion that the sources in the state
significantly contribute to nonattainment or interfere with maintenance
of the NAAQS (i.e., step 3).
    In interpreting the phrase ``emits or would emit in violation of
the prohibition of section [110(a)(2)(D)(i)],'' if the EPA or a state
has already adopted provisions that eliminate the significant
contribution to nonattainment or interference with maintenance of the
NAAQS in downwind states, then there simply is no violation of the CAA
section 110(a)(2)(D)(i)(I) prohibition. Stated another way, requiring
additional reductions from upwind sources would result in eliminating
emissions that do not contribute significantly to nonattainment or
interfere with maintenance of the NAAQS. Such an action is beyond the
scope of the prohibition in CAA section 110(a)(2)(D)(i)(I) and,
therefore, beyond the scope of the EPA's authority to make the
requested finding under CAA section 126(b). See EME Homer City, 134 S.
Ct. at 1604 n.18, 1608-09 (holding the EPA may not require sources in
upwind states to reduce emissions by more than necessary to eliminate
significant contribution to nonattainment or interference with
maintenance of the NAAQS in downwind states under the good neighbor
provision).
    Thus, it follows that if a state already has a SIP that the EPA
approved as adequate to meet the requirements of CAA section
110(a)(2)(D)(i)(I) for a specific NAAQS, the EPA would not find that a
source in that state was emitting in violation of the prohibition of
CAA section 110(a)(2)(D)(i)(I) absent new information demonstrating
that the SIP is now insufficient to address the prohibition for that
NAAQS. Similarly, if the EPA has promulgated a FIP that it has
determined fully eliminates emissions that significantly contribute to
nonattainment or interfere with maintenance in a downwind state for a
specific NAAQS, the EPA has no basis to find that sources in the upwind
state are emitting or would emit in violation of the CAA section
110(a)(2)(D)(i)(I) prohibition, absent new information to the contrary
for that NAAQS.
    The EPA notes that the approval of a SIP or promulgation of a FIP
implementing CAA section 110(a)(2)(D)(i)(I) constitutes a determination
that a state's emissions are adequately controlled considering the
specific facts that the EPA analyzed while approving the SIP or
promulgating the FIP. If a petitioner produces new data or information
showing a different level of contribution or other facts the EPA did
not consider when approving the SIP or promulgating the FIP, compliance
with a SIP or FIP may not be determinative regarding whether the upwind
sources emit or would emit in violation of the prohibition of CAA
section 110(a)(2)(D)(i)(I). See 64 FR 28250, 28274 n.15 (May 25, 1999);
71 FR 25328, 25336 n.6 (April 28, 2006);

Appalachian Power, 249 F.3d at 1067 (later developments can be the
basis for another CAA section 126 petition). Thus, in circumstances
where a state is implementing a SIP or the EPA is implementing a FIP
addressing CAA section 110(a)(2)(D)(i)(I), the EPA will evaluate the
CAA section 126(b) petition to determine if the submitted petition
raises new information that merits further consideration.

B. The EPA's Evaluation of Whether the Petition Is Sufficient To
Support a CAA Section 126(b) Finding

    Consistent with the EPA's approach to evaluating several prior CAA
section 126(b) petitions, the EPA interprets CAA section 126(b) as
placing an initial burden on the petitioner to establish a technical
basis for the specific finding requested. Thus, the EPA first looks to
see if the petition identifies or contains a sufficient basis to make
the requested finding. See, e.g., 76 FR 19662, 19666 (April 7, 2011)
(proposed response to petition from New Jersey regarding SO2
emissions from the Portland Generating Station); 83 FR 16064, 16070
(April 13, 2018) (final response to petition from Connecticut regarding
ozone emissions from the Brunner Island Steam Electric Station); 83 FR
50444, 50452 (October 5, 2018) (final response to petitions from
Delaware and Maryland regarding ozone emissions from four and 36 EGUs,
respectively).
    The EPA's interpretation of the statute is reasonable especially
given the expeditious and limited timeframe Congress allotted to the
EPA for action on a CAA section 126(b) petition: As described in
Section III.D.5, Congress provided the EPA with only 60 days from its
receipt of a CAA section 126(b) petition to hold a hearing and act on
that petition. Given the short statutory deadline, it is reasonable for
the EPA to conclude that Congress did not intend a requirement that the
EPA undertake extensive fact-finding or independent analysis as part of
its action on a petition and instead place the burden upon the
petitioner to provide adequate support for a requested finding under
CAA section 126(b), an interpretation affirmed by the courts. See New
York v. EPA, 852 F.2d 574 (D.C. Cir. 1988) (upholding the EPA's
interpretation of the statutory burden in reviewing the EPA's denial of
separate CAA section 126(b) petitions filed by Pennsylvania, Maine, and
New York regarding air quality impacts from numerous sources located in
seven midwestern states); see also see also Citizens Against Ruining
the Environment v. EPA, 535 F.3d 670 (7th Cir.) (2008) (affirming the
EPA's similar interpretation of the petitioner's burden under CAA
section 502(b)(2) given the parallel 60-day deadline for the EPA to
respond to a title V petition). In New York v. EPA, the D.C. Circuit
evaluated the EPA's obligation in acting on a CAA section 126(b)
petition, determining both that the 60-day deadline for action meant
Congress did not intend for the EPA to undertake a ``litany of tasks''
in evaluating the petition and that denial was proper where the states
failed to substantiate the claims raised in their petitions. Id.
Accordingly, where a CAA section 126(b) petition does not contain
sufficient technical information or justification to support the
requested finding without the EPA undertaking an independent analysis,
it is reasonable for the EPA to interpret CAA section 126(b) to support
a denial of the petition.
    The remedy provision under CAA section 126(c) further supports the
reasonableness of the EPA's interpretation. CAA section 126(c) by
default requires an existing source to cease operation within 3 months
if the EPA makes the requested finding under CAA section 126(b). It is
difficult to imagine that Congress intended to require sources to shut
down entirely absent a sufficient demonstration that that such an
extreme remedy was necessary. This concern is exacerbated by the
provision of CAA section 126(b) that permits a petitioner to target
``groups of sources,'' as New York did in the petition that is subject
to this action, because Congress certainly could not have envisioned
that hundreds of stationary sources would be required to shut down
within 3 months without a complete and compelling justification. The
potential for such an unintended consequence further supports the
placement of burden on the petitioner to demonstrate in the first
instance whether the identified sources emit or would emit in violation
of the good neighbor provision. While CAA section 126(c) provides in
the alternative that the EPA may permit continued operation if it
establishes emissions limitations for the sources subject to the
finding, this too is a detailed analytic task that requires time and
resources to develop.
    While the EPA interprets CAA section 126(b) as putting the burden
on the petitioner, rather than the EPA, to provide a basis or
justification for making the requested finding, nothing precludes the
EPA from choosing to conduct an independent analysis on a discretionary
basis when the Agency determines it would be helpful in evaluating a
petition. As discussed in Section III, the EPA has chosen to invoke its
discretion in prior actions on CAA section 126(b) petitions concerning
ozone, primarily where the Agency already had technical data or
findings it could rely on as part of its independent analysis. Notably,
because this supplemental information already existed at the time the
EPA acted on those petitions, the EPA could leverage such information
in its action without undertaking new analyses that would naturally
take significantly more time and resources to develop.\36\ As further
described in Sections IV.B.1-3, where the EPA has existing relevant
information at its disposal that could help inform its proposed
decision on New York's section 126(b) petition, the EPA is using such
information as part of its discretionary independent analysis of the
petition.
---------------------------------------------------------------------------

    \36\ See 83 FR 16064 (April 13, 2018); 83 FR 50444 (October 5,
2018).
---------------------------------------------------------------------------

1. The EPA's Evaluation of New York's Petition Considering Step 1
    With respect to step 1 of the four-step interstate transport
framework, the EPA began by evaluating New York's petition to determine
whether the state identified a downwind air quality problem
(nonattainment or maintenance) that may be impacted by ozone transport
from other states. The EPA conducted this evaluation for Chautauqua
County and the NYMA regarding both the 2008 and 2015 ozone NAAQS.
    As discussed in Section III.C, the EPA typically focuses its
analysis regarding potential downwind air quality problems on a future
analytic year given the forward-looking nature of the good neighbor
obligation in CAA section 110(a)(2)(D)(i)(I). The good neighbor
provision requires that states prohibit emissions that ``will''
significantly contribute to nonattainment or interfere with maintenance
of the NAAQS in any other state. The EPA reasonably interprets this
language as permitting states and the EPA in implementing the good
neighbor provision to prospectively evaluate downwind air quality
problems and the need for further upwind emissions reductions. In the
EPA's prior regional transport rulemakings, the Agency generally
evaluated whether upwind states ``will'' have such an impact based on
projections of air quality in the future year that considers the
timeframes for regionwide implementation of control strategies and the
timeframe in which a rulemaking requiring such controls would be
finalized. For the 1998 NOX SIP Call, the EPA used an
analytic year of 2007. For the 2005 CAIR, the EPA

used analytic years of 2009 and 2010 for ozone and PM2.5,
respectively. 63 FR 57450; 70 FR 25241. The D.C. Circuit affirmed the
EPA's interpretation of ``will'' in CAIR, finding the EPA's
consideration of future projected air quality (in addition to current
measured data) to be a reasonable interpretation of an ambiguous term.
North Carolina, 531 F.3d at 913-14. The EPA applied the same approach
in finalizing CSAPR in 2011 and the CSAPR Update in 2016 by evaluating
air quality in 2012 and 2017, respectively. 76 FR 48211; 81 FR 74537.
    Particularly relevant to this action, the EPA also applied this
interpretation of ``will'' in the 2018 Determination Rule to evaluate
remaining good neighbor obligations with respect to the 2008 ozone
NAAQS for the CSAPR Update states, including the nine upwind states
cited in New York's petition. 83 FR 65889-90. As explained in that
action, a key decision informing the application of the interstate
transport framework is the selection of a future analytic year. Several
court decisions have guided the factors that the EPA considers in
selecting an appropriate future analytic year for such an analysis.
First, in North Carolina, the D.C. Circuit held that the timeframe for
implementation of emissions reductions required by the good neighbor
provision should be selected by considering the relevant attainment
dates of downwind nonattainment areas affected by interstate transport
of air pollution. 531 F.3d at 911-12. Moreover, the Supreme Court and
the D.C. Circuit have both held that the EPA may not over-control
upwind state emissions relative to the downwind air quality problems.
Specifically, the courts found that the Agency may not require
emissions reductions (at steps 3 and 4 of the interstate transport
framework) from a state that are greater than necessary to achieve
attainment and maintenance of the NAAQS in all the downwind areas to
which that state is linked. See EME Homer City, 134 S. Ct. at 1600-01;
EME Homer City II, 795 F.3d at 127, 129-30 (on remand from the Supreme
Court, finding ozone-season NOX budgets for ten states
invalid because the EPA's modeling showed that the downwind air quality
problems to which these states were linked would be resolved by the
time the budgets would be implemented). These court decisions support
the Agency's choice to use a future analytic year to help ensure that
any emissions reductions that the EPA may require of sources in upwind
states do not over- or under-control emissions with respect to downwind
air quality at the time by which that those controls could feasibly be
implemented.
    Thus, in determining the appropriate future analytic year for
purposes of assessing remaining interstate transport obligations for
the 2008 ozone NAAQS in the Determination Rule, the EPA considered two
primary factors: (1) The applicable attainment dates for the 2008 ozone
NAAQS; and (2) the timing to feasibly implement new NOX
control strategies not previously addressed in the CSAPR Update. As the
applicable attainment dates, the EPA explained that the next attainment
dates for the 2008 ozone NAAQS would be July 20, 2021, for
nonattainment areas classified as Serious, and July 20, 2027, for
nonattainment areas classified as Severe.
    The EPA then evaluated the timeframe necessary to implement
additional NOX control strategies at various sources across
the region. For EGUs, the EPA explained that it was appropriate to give
particular weight to the timeframe required for implementation of
selective catalytic reduction (SCR) across the region because of the
potential for larger emissions reductions as compared to selective non-
catalytic reduction (SNCR). The EPA determined that SCR project
development and installation may require up to 39 months for an
individual power plant installing controls on more than one boiler,\37\
and that a minimum of 48 months (4 years) is a reasonable time-period
to allow to complete all necessary steps of SCR projects at EGUs on a
regional scale, considering the necessary stages of post-combustion
control project planning, shepherding of labor and material supply,
installation, coordination of outages, testing, and operation. The EPA
further concluded that SNCR installations, while generally having
shorter project timeframes (i.e., up to 16 months for an individual
power plant installing controls on more than one boiler), share similar
implementation steps with and need to account for the same regional
factors as SCR installations.\38\ The EPA, therefore, concluded that it
may reasonably take up to 4 years to install the new emissions controls
regionwide for EGUs. 83 FR 65893-901.
---------------------------------------------------------------------------

    \37\ See Table 3-1 in Engineering and Economic Factors Affecting
the Installation of Control Technologies for Multipollutant
Strategies. EPA Final Report. EPA-600/R-02/073. October 2002.
Available at https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NRMRL&dirEntryId=63473.
    \38\ See the month-by-month evaluation of SNCR installation
presented in Exhibit A-6 in Engineering and Economic Factors
Affecting the Installation of Control Technologies for
Multipollutant Strategies. EPA Final Report. EPA-600/R-02/073.
October 2002. Available at https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NRMRL&dirEntryId=63473. Evaluation
is also in the EPA's CSAPR Update EGU NOX Mitigation
Strategies Final Rule TSD. See Docket ID No. EPA-HQ-OAR-2015-0500
(available at http://www.regulations.gov).
---------------------------------------------------------------------------

    The EPA further explained that many of the same considerations
affecting the EPA's analysis of regionwide implementation of controls
at EGUs would also affect the regionwide implementation of controls at
non-EGUs, which may be more complex considering the diversity of non-
EGU sources as well as the greater number and smaller size of the
individual sources. The EPA noted that preliminary estimates for the
implementation of some potential control technologies on non-EGUs only
account for the time between bid evaluation and startup but do not
account for additional considerations such as pre-bid evaluation
studies, permitting, and installation of monitoring equipment.
Accordingly, the EPA concluded that it was reasonable to assume for
purposes of the Determination Rule that an expeditious timeframe for
installing sector- or region-wide controls on non-EGU sources could
also be 4 years or more. 83 FR 65901-04.
    Considering the timeframes for regionwide implementation of control
strategies and the timeframe in which a rulemaking requiring such
controls would be finalized, the EPA concluded that reductions from
such control strategies were unlikely to be implemented for a full
ozone season until 2023. The EPA acknowledged that 2023 is later than
the attainment date for nonattainment areas classified as Serious (July
20, 2021), but concluded that it was unlikely emissions control
requirements could be feasibly promulgated and implemented by that
earlier date. Accordingly, the EPA determined that 2023 was a
reasonable year to assess downwind air quality to evaluate any
remaining requirements under the good neighbor provision for the 2008
ozone NAAQS.\39\ 83 FR 65901-05.
---------------------------------------------------------------------------

    \39\ Using the 2023 analytic year also allowed the EPA to begin
the updated analysis using the data sets originally developed for a
January 2017 Notice of Data Availability (NODA) (82 FR 1733, January
6, 2017), which the EPA revised in response to stakeholder feedback.
Accordingly, the EPA initiated its analysis more quickly than if a
different year had been chosen, which might have delayed subsequent
rulemaking actions and therefore emissions reductions.
---------------------------------------------------------------------------

    After selecting the analytic year, the EPA then used the
Comprehensive Air Quality Model with Extensions (CAMx v6.40) to model
emissions in 2011 and

2023, based on updates provided to the EPA from states and other
stakeholders in the January 6, 2017 NODA and an October 27, 2017, EPA
memorandum.\40\ This updated modeling was used in the Determination
Rule to estimate ozone design values in 2023, as described in the
Determination Rule Air Quality Modeling Technical Support Document
(TSD).\41\ The EPA used outputs from the 2011 and 2023 model
simulations to project base period 2009-2013 average and maximum ozone
design values to 2023 at monitoring sites nationwide. In projecting
future year design values, the EPA applied its own modeling
guidance,\42\ which recommends using model predictions from the ``3 x
3'' array of grid cells surrounding the location of the monitoring
site.\43\ Considering the comments on the January 2017 NODA and other
analyses, the EPA also projected 2023 design values based on a modified
version of the ``3 x 3'' approach for those monitoring sites located in
coastal areas. Briefly, in this alternative approach, the EPA
eliminated from the design value calculations those modeling data in
grid cells that are dominated by water (i.e., more than 50 percent of
the area in the grid cell is water) and that do not contain a
monitoring site (i.e., if a grid cell is more than 50 percent water but
contains an air quality monitor, that cell would remain in the
calculation).\44\ For each individual monitoring site, the base period
2009-2013 average and maximum design values, 2023 projected average and
maximum design values based on both the ``3 x 3'' approach and the
alternative approach affecting coastal sites are available in Excel
format in the docket for this action and at https://www.epa.gov/airmarkets/october-2017-memo-and-information-interstate-transport-sips-2008-ozone-naaqs.
---------------------------------------------------------------------------

    \40\ See Notice of Availability of the Environmental Protection
Agency's Preliminary Interstate Ozone Transport Modeling Data for
the 2015 Ozone National Ambient Air Quality Standard (NAAQS), 82 FR
1733 (January 6, 2017). This memorandum also supplements the
information provided in, ``Supplemental Information on the
Interstate Transport State Implementation Plan Submissions for the
2008 Ozone National Ambient Air Quality Standards under Clean Air
Act Section 110(a)(2)(D)(i)(I).'' Memorandum from Stephen D. Page,
Director, U.S. EPA Office of Air Quality Planning and Standards, to
Regional Air Division Directors, Regions 1-10. October 27, 2017.
Available at https://www.epa.gov/sites/production/files/2017-10/documents/final_2008_o3_naaqs_transport_memo_10-27-17b.pdf.
    \41\ Air Quality Modeling Technical Support Document for the
Updated 2023 Projected Ozone Design Values. U.S. EPA Office of Air
Quality Planning and Standards. June 2018. Document developed to
support the Determination Rule, 83 FR 65878 (December 21, 2018).
Available at https://www.epa.gov/airmarkets/air-quality-modeling-technical-support-document-updated-2023-projected-ozone-design.
    \42\ ``Draft Modeling Guidance for Demonstrating Attainment of
Air Quality Goals for Ozone, PM2.5, and Regional Haze.''
Memorandum from Richard Wayland, Division Director, Air Quality
Assessment Division, U.S. EPA Office of Air Quality Planning and
Standards, to Regional Air Division Directors, Regions 1-10.
December 3, 2014. Available at https://www3.epa.gov/scram001/guidance/guide/Draft-O3-PM-RH-Modeling_Guidance-2014.pdf.
    \43\ The EPA's modeling uses 12 km\2\ grid cells.
    \44\ A model grid cell is identified as a ``water'' cell if more
than 50 percent of the grid cell is water based on the 2006 National
Land Cover Database. Grid cells that meet this criterion are treated
as entirely over water in the WRF modeling used to develop the 2011
meteorology for the EPA's air quality modeling. (See Air Quality
Modeling Technical Support Document for the Updated 2023 Projected
Ozone Design Values. U.S. EPA Office of Air Quality Planning and
Standards. June 2018. Document developed to support the
Determination Rule, 83 FR 65878 (December 21, 2018). Available at
https://www.epa.gov/airmarkets/air-quality-modeling-technical-support-document-updated-2023-projected-ozone-design.)
---------------------------------------------------------------------------

    In the Determination Rule, the EPA followed the same approach for
identifying receptors based on this modeling as in the CSAPR Update
rulemaking process. That is, the EPA considered a combination of
modeling projections and monitoring data to identify receptor sites
that are projected to have problems attaining or maintaining the
NAAQS.\45\ Specifically, the EPA identified nonattainment receptors as
those monitoring sites with current measured values exceeding the NAAQS
that also have projected (i.e., in 2023) average design values
exceeding the NAAQS. The EPA also identified maintenance receptors as
those monitoring sites with projected maximum design values exceeding
the NAAQS. Specifically, maintenance receptors included sites with
current measured values below the NAAQS with projected average and
maximum design values exceeding the NAAQS and monitoring sites with
projected average design values below the NAAQS but with projected
maximum design values exceeding the NAAQS.
---------------------------------------------------------------------------

    \45\ See 81 FR 74530-74532 (October 26, 2016).
---------------------------------------------------------------------------

    Pertinent to this action, the EPA's examination in the
Determination Rule of the 2023 projected design values for Chautauqua
County indicates that this area is not projected to be in nonattainment
or have a maintenance problem in 2023 for either the 2008 or the 2015
ozone NAAQS. The EPA's examination of the 2023 projected design values
for the NYMA indicates that this area is not projected to be in
nonattainment or have a maintenance problem in 2023 for the 2008 ozone
NAAQS. However, the modeling indicates that the NYMA is projected to be
in nonattainment in 2023 with respect to the 2015 ozone NAAQS.
    Because the EPA has already conducted a rulemaking evaluating good
neighbor obligations for the 2008 ozone NAAQS under CAA section
110(a)(2)(D)(i)(I) and because, as discussed previously, CAA section
126(b) directly incorporates the CAA section 110(a)(2)(D)(i) standard,
the EPA believes it is also appropriate to consider the 2023 modeling
conducted for the Determination Rule in evaluating whether New York's
petition has adequately demonstrated that there will be a downwind air
quality problem with respect to the 2008 ozone NAAQS in Chautauqua
County and the NYMA. Moreover, the EPA believes it is appropriate to
consider the 2023 modeling when evaluating the petition's claims with
respect to the 2015 ozone NAAQS because the 2023 ozone season aligns
with the attainment year for Moderate ozone nonattainment areas.\46\
While the EPA is not reopening the analysis and findings made in the
Determination Rule with respect to the 2008 ozone NAAQS in this action,
the EPA is evaluating the petition, consistent with the standard of
review described in Section IV.A, to determine whether additional
information not considered in the Determination Rule should influence
the EPA's finding as to whether the sources named in New York's
petition emit or would emit in violation of the prohibition of CAA
section 110(a)(2)(D)(i)(I).
---------------------------------------------------------------------------

    \46\ The 2023 ozone season represents the last full season from
which data can be used to determine attainment with the 2015 ozone
NAAQS by the August 3, 2024, attainment date for nonattainment areas
classified as Moderate.
---------------------------------------------------------------------------

    The EPA notes that the petition asserts that the EPA cannot use its
2023 modeling to support a review of the petition in part because the
2023 analytic year does not fit the timeframe under CAA section 126(c),
which requires that compliance with any CAA section 126(b) finding must
be met ``in no case later than three years after the date'' of such
finding. However, the EPA's evaluation of air quality in 2023 is a
necessary step to determine whether the sources named in New York's
petition are in violation of the good neighbor provision in the first
instance, and, thus, subject to the provisions of CAA section 126(c).
Moreover, the choice of 2023 as an analytic year does not preclude the
implementation of a remedy in an earlier year if the necessary finding
is made under CAA section 126(b). If the EPA were to determine based on
its analysis of the 2023 projections that the named sources emit or
would emit in violation of the good neighbor provision, the EPA could

still implement a remedy that complies with the earlier timeline set
out under CAA section 126(c). Therefore, the EPA's reasonable choice of
2023 as an analytic year for evaluating New York's petition does not,
in and of itself, preclude implementation of a remedy at an earlier
date.
    The New York petition further raises concerns about the assumptions
and results of the EPA's modeling. Specifically, the petition indicates
significant concerns with the EPA's expectation that uncontrolled EGUs
will greatly reduce their emissions rates in the absence of unit-level
enforceable limits and with the EPA's treatment of model cells
containing a land/water interface. The petition does not further
elaborate on the basis for these concerns, and the EPA, therefore, has
no reason to believe that its 2023 modeling is unreliable. Moreover,
the EPA already addressed concerns regarding the EGU assumptions in the
2023 modeling in response to comments raised in the Determination Rule.
See 83 FR 65886-89 (explaining statutory rationale regarding when
enforceable emissions limitations are required and responding to
comments); 83 FR 65913-15 (responding to comments concerning
projections of EGU emissions in 2023). As described earlier in this
section, the EPA also addressed concerns regarding the treatment of
model cells containing land/water interface in the Determination Rule
by calculating design values using two different methodologies. The
petition does not provide any new information not already considered by
the EPA in the Determination Rule as to these issues and therefore, has
no basis to reconsider its conclusions finalized in that action.
    The next two sections discuss the EPA's evaluation of the
petition's step 1 analysis regarding Chautauqua County and the NYMA
with respect to both the 2008 and 2015 ozone NAAQS. The EPA first
evaluates the sufficiency of the analysis provided in the petition for
each area and then considers how the 2023 modeling or other pertinent
information should inform the EPA's conclusion regarding whether there
will be downwind nonattainment or maintenance concerns in each area
with respect to each NAAQS.
Chautauqua County
    First, for Chautauqua County, New York's petition does not provide
sufficient information to demonstrate that there will be a downwind
nonattainment or maintenance problem with respect to either the 2008 or
the 2015 ozone NAAQS. Although the petition correctly indicates that
the EPA previously designated Chautauqua County as Marginal
nonattainment under the 2008 ozone NAAQS, the petition did not
demonstrate that there will be a future nonattainment or maintenance
problem in that area for that NAAQS that must be addressed under the
good neighbor provision. While a prior designation of an area as
nonattainment may provide useful information for purposes of analyzing
interstate transport under the good neighbor provision, designations
themselves are not dispositive of whether a downwind area will have an
air quality problem in the future.\47\ As discussed earlier, the EPA
evaluates downwind ozone air quality problems for purposes of step 1 of
the four-step interstate transport framework using observed and modeled
future air quality concentrations for a year that considers the
relevant attainment deadlines for the NAAQS and the anticipated
compliance timeframe for potential control strategies.\48\ New York's
section 126(b) petition does not include analyses indicating that
Chautauqua County may be violating or have difficulty maintaining the
2008 or 2015 ozone NAAQS either currently or in a relevant future year.
In fact, the petition acknowledges that this area attained the NAAQS by
the relevant attainment date. The petition also did not present air
quality projections indicating that Chautauqua County will not be in
attainment or will struggle to maintain the NAAQS in a relevant future
year. The petition alleges that the area remains in danger of exceeding
the ozone NAAQS but does not provide any evidence to support this
assertion. Thus, the petition has not established that emissions from
the named sources are linked to a nonattainment or maintenance problem
in Chautauqua County.
---------------------------------------------------------------------------

    \47\ The EPA has consistently taken the position that CAA
section 110(a)(2)(D) refers to prevention of ``nonattainment'' in
any area in another state, not only in designated nonattainment
areas. See, e.g., Clean Air Interstate Rule, 70 FR 25162, 25265 (May
12, 2005); Cross-State Air Pollution Rule, 76 FR 48208, 48211 (Aug.
8, 2011); Final Response to Petition from New Jersey Regarding
SO2 Emissions From the Portland Generating Station, 76 FR
69052 (Nov. 7, 2011) (finding facility in violation of the
prohibitions of CAA section 110(a)(2)(D)(i)(I) with respect to the
2010 SO2 NAAQS prior to issuance of designations for that
standard).
    \48\ 81 FR 74517.
---------------------------------------------------------------------------

    Additionally, the EPA has air quality data that support an
independent analysis of step 1 of the four-step interstate transport
framework to assess whether Chautauqua County will have an air quality
problem relative to either the 2008 or the 2015 ozone NAAQS. First, the
2015-2017 design value in Chautauqua County is 68 ppb, which is below
the level of both the 2008 and 2015 ozone NAAQS.\49\ Furthermore, the
EPA recently finalized a determination that the Jamestown, New York
Marginal nonattainment area (Chautauqua County) has attained the 2008
ozone NAAQS.\50\ Additionally, the EPA's recent air quality modeling
described earlier in this section indicates that the monitor in
Chautauqua County is expected to continue to both attain and maintain
the standard in 2023, with an average 2023 design value of 58.5 ppb and
a maximum 2023 design value of 60.7 ppb.\51\ Consequently, due to the
facts that the petition has not identified an air quality problem in
Chautauqua County for the 2008 or 2015 ozone NAAQS, that the EPA's
independent analysis affirms that Chautauqua County is attaining both
the 2008 and 2015 ozone NAAQS, and that all available evidence
indicates that the monitoring sites will continue to attain and
maintain the NAAQS in the future, the EPA is proposing to deny New
York's petition regarding Chautauqua County for both the 2008 and the
2015 ozone NAAQS.
---------------------------------------------------------------------------

    \49\ The 2015-2017 design value for Chautauqua County in the
``Jamestown-Dunkirk-Fredonia, NY CBSA'' at AQS site 360130006 is 68
ppb. Available at https://www.epa.gov/sites/production/files/2018-07/ozone_designvalues_20152017_final_07_24_18.xlsx.
    \50\ See Approval and Promulgation of Air Quality Implementation
Plans; New York; Determination of Attainment of the 2008 8-Hour
Ozone National Ambient Air Quality Standard for the Jamestown, New
York Marginal Nonattainment Area, 83 FR 49492 (October 2, 2018).
    \51\ See 2023 design values for AQS site 360130006 in
spreadsheet released with the EPA's March 2018 memorandum. Available
at https://www.epa.gov/sites/production/files/2018-05/updated_2023_modeling_dvs_collective_contributions.xlsx.
---------------------------------------------------------------------------

New York Metropolitan Area
    Second, with respect to the NYMA, the petition does not provide
sufficient information to indicate that there will be a future
nonattainment or maintenance problem with respect to the 2008 ozone
NAAQS. As described in Section III.D of this notice, the petition
correctly asserts that the NYMA was designated nonattainment for the
2008 ozone NAAQS and has failed to attain the NAAQS by the attainment
deadline. Additionally, the petition points to preliminary 2015-2017
air quality data indicating that some monitoring sites in the NYMA are
above the 2008 NAAQS. However, the EPA does not agree that an area's
current attainment status alone is sufficient evidence regarding
whether there will be a nonattainment or maintenance problem that must
be addressed under either the good neighbor provision or CAA section
126.

Rather, as previously discussed, the EPA evaluates whether there will
be downwind nonattainment or maintenance concerns in each area with
respect to each NAAQS under the good neighbor provision (and, thus,
also under CAA section 126(b)) using observed and modeled future air
quality concentrations for a relevant future analytic year.
    Further, the EPA has additional information related to potential
projected nonattainment or maintenance problems in the NYMA. The EPA's
recent air quality projections for 2023, based on the latest available
emissions inventory, indicate that all monitoring sites in the NYMA
will attain and maintain the 2008 ozone NAAQS. As discussed in Section
III.C.2 of this notice, the EPA already determined that the CSAPR
Update fully addresses the good neighbor provision requirements for the
2008 ozone NAAQS for all eastern states previously addressed in that
rule. This analysis indicates that all remaining receptors for the 2008
ozone NAAQS identified in the CSAPR Update, including those in the
NYMA, are expected to attain and maintain that NAAQS in 2023 under step
1 of the four-step interstate transport framework, and, therefore,
upwind states have no remaining obligations under the good neighbor
provision. New York has not provided any new information that
contradicts the EPA's conclusion in the Determination Rule that the
NYMA will no longer have an air quality problem in the future.
Therefore, the EPA is proposing to deny New York's petition regarding
the 2008 ozone NAAQS in the NYMA because New York has not demonstrated
that there will be a nonattainment or maintenance problem in the NYMA
in a relevant future year and the EPA's own analysis projects that
there will be no air quality problems under step 1.
    Regarding the 2015 ozone NAAQS, the EPA's projections indicate that
the average design value for five of the six monitoring sites in the
NYMA and the maximum design values at all six monitoring sites in the
NYMA will be above the 2015 ozone NAAQS in 2023.\52\ Therefore,
although New York did not evaluate whether there will be an air quality
problem with respect to the 2015 ozone NAAQS in a future year, the
EPA's independent analysis of step 1 of the interstate transport
framework indicates that the NYMA is projected to have a downwind air
quality problem relative to the 2015 NAAQS.
---------------------------------------------------------------------------

    \52\ The EPA also notes that four of the six monitoring sites
are in the state of Connecticut and two monitoring sites are in New
York. However, the EPA interprets CAA section 126(b)'s petition
authority to be limited to states and political subdivisions seeking
to address interstate transport of pollution impacting downwind
receptors within their geographical borders. See 83 FR 50460.
---------------------------------------------------------------------------

2. The EPA's Evaluation of New York's Petition Considering Step 2
    With respect to step 2 of the four-step interstate transport
framework, the EPA evaluated New York's petition to determine whether
there is sufficient information to conclude that the state identified
that the upwind states where the sources named in the petition are
located are linked to a downwind air quality problem. Because, as
described earlier, neither the information in the petition nor existing
information available to the EPA indicates there will be downwind
nonattainment or maintenance concerns in Chautauqua County with respect
to the 2008 and 2015 ozone NAAQS, or in the NYMA with respect to the
2008 ozone NAAQS, the EPA has no basis to find a linkage at step 2 of
the four-step framework between the named upwind states and these
downwind areas with regard to the respective NAAQS.
    With respect to the NYMA for the 2015 ozone NAAQS, existing
information available to the EPA supports an assessment that emissions
from at least some of the states named in the petition are linked to a
downwind air quality problem at step 2. As the following paragraphs
explain, the linkages between upwind and downwind states are further
informed by an air quality screening threshold.
    Historically, at step 2, the EPA has used an air quality screening
threshold to determine whether a state contributes to a downwind air
quality problem in amounts that warrant further evaluation as part of a
multi-factor analysis in step 3. Upwind states that impact a downwind
receptor by less than the screening threshold do not contribute to the
downwind air quality problem at step 2. The EPA has therefore
previously determined, without conducting any additional analysis, that
such states do not significantly contribute to nonattainment or
interfere with maintenance of the NAAQS under the good neighbor
provision. Upwind states that impact a downwind receptor at or above
the threshold are identified as contributing to a downwind air quality
problem (i.e., they are said to be ``linked'' to that downwind
receptor). The EPA then proceeds to the multi-factor step 3 analysis to
determine if the linked upwind state significantly contributes to
nonattainment or interferes with maintenance of the NAAQS at the
downwind receptor(s).\53\
---------------------------------------------------------------------------

    \53\ Note that upwind states that are linked to a downwind
receptor at step 2 may nevertheless be found to not significantly
contribute to nonattainment or interfere with maintenance at the
receptor depending on the outcome of the step 3 analysis.
---------------------------------------------------------------------------

    In previous federal actions,\54\ the EPA's analysis of the sum of
contributions from all linked upwind states (i.e., collective
contribution) concluded that a screening threshold equivalent to 1
percent of the 1997 and 2008 ozone NAAQS was appropriate at step 2. In
an August 31, 2018, memorandum, the EPA presented the results of our
analysis of collective contribution for the 2015 ozone NAAQS \55\ using
data drawn from the results of the EPA's updated 2023 modeling.\56\
This analysis, which followed the thresholds analyses conducted in both
the CSAPR and CSAPR Update rulemakings,57 58 included the
evaluation of data pertinent to several potential thresholds (i.e., 1
percent of the 2015 ozone NAAQS or 0.70 ppb, 1 ppb and 2 ppb) that
could be applicable to the development of SIP revisions to address the
2015 ozone NAAQS of 70 ppb. The EPA ultimately suggested in this
memorandum that a threshold of 1 ppb may be appropriate for states to
use to develop SIP revisions addressing the good neighbor provision for
the 2015 ozone NAAQS.
---------------------------------------------------------------------------

    \54\ In the Cross-State Air Pollution Rule (CSAPR), the EPA used
0.80 parts per billion (ppb) as the threshold, which is 1 percent of
the 1997 ozone NAAQS. 76 FR 48208, 48238 (August 8, 2011). Most
recently, in the Cross-State Air Pollution Rule Update for the 2008
Ozone NAAQS (CSAPR Update), the EPA used 0.75 ppb as the threshold,
which is 1 percent of the 2008 ozone NAAQS. 81 FR 74504, 74518
(October 26, 2016).
    \55\ See Analysis of Contribution Thresholds for Use in Clean
Air Act Section 110(a)(2)(D)(i)(I) Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards (August 31, 2018).
    \56\ Information on the Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards under Clean Air Act Section 110(a)(2)(D)(i)(I)
(March 2018). https://www.epa.gov/airmarkets/march-2018-memo-and-supplemental-information-regarding-interstate-transport-sips-2015.
    \57\ Air Quality Modeling Technical Support Document for the
Final Cross State Air Pollution Rule Update (August 2016). https://www.epa.gov/airmarkets/air-quality-modeling-technical-support-document-final-cross-state-air-pollution-rule.
    \58\ Air Quality Modeling Final Rule Technical Support Document
(for the Final Transport Rule now known as CSAPR; June 2011).
https://www.epa.gov/csapr/air-quality-modeling-final-rule-technical-support-document.
---------------------------------------------------------------------------

    In addition to the 2023 modeling used to identify potential
downwind air quality problems described in the prior section, the EPA
has also performed state-level ozone source apportionment

modeling to provide information regarding the expected contribution of
statewide, anthropogenic NOX and VOC emissions in each state
to projected 2023 ozone concentrations. If the EPA applies a 1 percent
threshold like that used in prior rulemakings (e.g., 0.70 ppb) to the
results of the contribution modeling, the EPA's analysis indicates that
all nine upwind states named in the petition are linked to an air
quality problem in the NYMA for the 2015 ozone NAAQS. If the EPA
instead applies the alternative 1 ppb threshold, the EPA's analysis
indicates that the sources in six (i.e., Maryland, Michigan, Ohio,
Pennsylvania, Virginia and West Virginia) of the nine states named in
New York's petition are linked to an air quality problem in the NYMA
for the 2015 ozone NAAQS, while three states (i.e., Illinois, Indiana
and Kentucky) are not.\59\ The EPA is not in this action determining
which of the potential thresholds described in this section (i.e., 1
percent of the NAAQS (0.70 ppb) or 1 ppb) is appropriate for addressing
collective contribution for the 2015 ozone NAAQS for purposes of New
York's petition. However, the EPA acknowledges that emissions from at
least some of the named upwind states are linked to projected air
quality problems in the NYMA for the 2015 ozone NAAQS. Therefore, the
EPA will evaluate, in the following section, whether the petition has
adequately demonstrated at step 3 of the four-step interstate transport
framework that the sources in the upwind states will significantly
contribute to nonattainment or interfere with maintenance of the NAAQS.
---------------------------------------------------------------------------

    \59\ As identified previously in this notice, the EPA's recent
modeling included essentially all the EGUs at the facilities named
in the New York petition. We say ``essentially'' because the New
York petition identifies sources at the facility, rather than at the
unit, level while the EPA looks at unit-level data and includes all
fossil-fuel-fired boiler or combustion turbine EGUs with a capacity
(electrical output) greater than 25 MW. See Information on the
Interstate Transport State Implementation Plan Submissions for the
2015 Ozone National Ambient Air Quality Standards under Clean Air
Act Section 110(a)(2)(D)(i)(I) (March 27, 2018).
---------------------------------------------------------------------------

3. The EPA's Evaluation of New York's Petition Considering Step 3
    As described in Section III.C.1 of this notice, once an upwind
state is linked to a downwind air quality problem at steps 1 and 2 of
the four-step interstate transport framework, the next step is to
identify the emissions reductions, if any, needed from particular
sources to eliminate the upwind state's significant contribution to
nonattainment and interference with maintenance of the NAAQS (i.e.,
step 3 of the four-step interstate transport framework).\60\ For the
reasons discussed in the following paragraphs, the EPA is proposing to
find that material elements in New York's assessment of step 3 are
insufficient, such that the EPA cannot conclude that any source or
group of sources in any of the named states will significantly
contribute to nonattainment or interfere with maintenance in Chautauqua
County or the NYMA relative to the 2008 and 2015 ozone NAAQS. Thus, the
EPA is proposing to deny the petition as to all named sources in all
the named upwind states because New York has not met its burden to
demonstrate that the sources emit or would emit in violation of the
good neighbor provision with respect to either the 2008 or 2015 ozone
NAAQS. We also note that the petition addresses hundreds of sources
across nine states. The EPA is taking comment on whether to also deny
the petition because the petitioner has not provided justification for
the proposition that identification of such a large, undifferentiated
number of sources located in numerous upwind states constitutes a
``group of stationary sources'' within the context of CAA section
126(b). For example, ``group of stationary sources'' could mean
stationary sources within a geographic region, sources identified by a
specific North American Industry Classification System (NAICS) Code,
sources emitting over a defined threshold and/or any combination of
these or other defining characteristics. Although the EPA already has
identified a sufficient basis to propose denial of the petition as to
Chautauqua County (for the 2008 and 2015 ozone NAAQS) and NYMA (for the
2008 ozone NAAQS) at step 1 of the four-step framework, the EPA is also
relying on our analysis of step 3 as an additional and independent
basis for denial as to the petition's claims for these areas.
---------------------------------------------------------------------------

    \60\ Contrary to New York's assertion in its petition,
identification of a linkage between an upwind state and a downwind
receptor does not conclude the determination regarding whether
sources in the upwind state will significantly contribute to
nonattainment or interfere with maintenance of the NAAQS. The
conclusion that a state's emissions met or exceeded the threshold
only indicated that further analysis was appropriate to determine
whether any of the upwind state's emissions met the statutory
criteria under the good neighbor provision. See EME Homer City, 134
S. Ct. at 1596-97 (noting upwind states are only obliged to
eliminate emissions meeting both the step 2 and 3 inquiries).
---------------------------------------------------------------------------

    As discussed in Section III.C.1 of this notice, within step 3 of
the four-step interstate transport framework, the EPA has historically
considered several factors to determine whether sources in linked
upwind states have emissions that will significantly contribute to
nonattainment or interfere with maintenance of the ozone NAAQS. In
particular, the EPA has generally considered various control, cost, and
air quality factors and data, including: The types of control
strategies that can be implemented at sources within the upwind states;
the costs of implementing such control strategies; the amount of
potential emissions reductions from implementation of control
strategies at upwind sources; the potential downwind air quality
improvements from such emissions reductions and the severity of the
downwind air quality problem (i.e., whether the air quality problem
will be resolved through implementation of the emissions reductions).
See 76 FR 48248-49 and 48254-55; 81 FR 74519; Ozone Transport Policy
Analysis Final Rule TSD, p. 3 (Docket ID No. EPA-HQ-OAR-2015-0500). The
EPA has typically considered these various cost and air quality factors
in a multifactor analysis to identify the appropriate uniform level of
emissions controls to apply to sources across a region of upwind states
that are collectively linked to downwind air quality problems and,
based on the selected level of control, to quantify the amount of
emissions (if any) from each upwind state that contribute to
nonattainment or interfere with maintenance in a downwind area and,
thus, should be subject to control.\61\ In these prior rules, the EPA
has selected the level of control stringency deemed cost-effective when
these factors are balanced together. Assessing multiple factors allows
the EPA to consider the full range of circumstances and state-specific
factors that affect the relationship between upwind emissions and
downwind nonattainment and maintenance problems. For example, the EPA's
assessment of cost considerations accounts for the existing level of
controls at sources in upwind states as well as the potential for, and
relative

difficulty of, achieving additional emissions reductions.\62\
Additionally, assessment of the downwind air quality impacts from the
potential upwind emissions reductions is essential to determining
whether various levels of potential control stringency would under- or
over-control upwind state emissions relative to the identified downwind
air quality problems. The Supreme Court has found the EPA's approach to
apportioning emissions reduction responsibility among multiple upwind
states to be ``an efficient and equitable solution to the allocation
problem'' presented by the good neighbor provision for regional
problems like the transport of ozone pollution. EME Homer City, 134 S.
Ct. at 1607.
---------------------------------------------------------------------------

    \61\ For example, in the CSAPR Update (81 FR 74505), the EPA
noted that ozone transport occurs on a regional scale, that such
transport is responsive to changes in NOX emissions, and
that NOX emissions reductions from EGUs were effective in
reducing 8-hour peak ozone concentrations during the ozone season.
Accordingly, the EPA selected a uniform control stringency to apply
to states covered by the rule by identifying the emissions reduction
potential from EGUs in linked upwind states available at various
levels of control stringency represented by cost, assessed how these
potential emissions reductions would affect each state's air quality
contributions to each receptor, evaluated the total change in air
quality at each receptor resulting from the emissions reductions,
and evaluated whether the air quality problems at each receptor
would be resolved. The EPA applied a similar approach in the CSAPR
Final Rule. 76 FR 48248 (August 8, 2011).
    \62\ See CSAPR Final Rule. 76 FR 48248 (August 8, 2011).
---------------------------------------------------------------------------

    As discussed in Section IV.A, the EPA interprets the substantive
standard under CAA section 126(b) consistent with its interpretation of
the good neighbor provision in CAA section 110(a)(2)(D)(i).
Accordingly, the EPA believes it could be reasonable to consider the
same factors whether evaluating ozone transport in the context of a
good neighbor SIP under CAA section 110 or a section 126(b) petition.
Thus, the EPA has reviewed New York's petition to determine whether it
has provided sufficient information to support a determination based on
the same type of cost and air quality factors that the EPA evaluated in
past rulemakings addressing regional ozone transport under the good
neighbor provision. The EPA notes that it considered these factors in
the CSAPR Update and implemented emissions reductions found to be cost-
effective at EGUs (including within the upwind states identified in New
York's petition) by the 2017 ozone season, but it did not evaluate
potential control strategies available on a longer implementation
timeframe or at non-EGUs. 81 FR 74521-22. The EPA has not conducted a
regional step 3 analysis for any sources with respect to the 2015 ozone
NAAQS, but nonetheless believes consideration of the same type of cost
and air quality factors could be reasonable for evaluating upwind state
obligations under the good neighbor provision for that standard.
    The EPA's review of the petition indicates that New York has not