[Federal Register Volume 86, Number 71 (Thursday, April 15, 2021)]
[Proposed Rules]
[Pages 19793-19812]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-07334]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R03-OAR-2020-0703; FRL-10021-94-Region 3]


Approval and Promulgation of Air Quality Implementation Plans; 
District of Columbia; Regional Haze State Implementation Plan for the 
Second Implementation Period and Reasonably Available Control 
Technology for Major Stationary Sources of Nitrogen Oxides; Technical 
Amendment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve the regional haze state implementation plan (SIP) submitted by 
the District of Columbia (``the District'' or ``DC'') through the 
Department of Energy and Environment (DOEE) on November 8, 2019, as 
satisfying applicable requirements under the Clean Air Act (CAA) and 
EPA's Regional Haze Rule (RHR) for the program's second implementation 
period. The District's SIP submission addresses the requirement that 
states must periodically revise their long-term strategies for making 
reasonable progress towards the national goal of preventing any future, 
and remedying any existing, anthropogenic impairment of visibility in 
mandatory Class I Federal areas, including regional haze. EPA is taking 
this action pursuant to sections 110 and 169A of the CAA. EPA is also 
proposing to correct an error in the citations in our final approval of 
the District's revision to the Reasonably Available Control Technology 
for Major Stationary Sources of Nitrogen Oxides Rule (``DC 
NOX RACT rule'') according to our authority under Section 
110(k)(6) of the CAA.

DATES: Written comments must be received on or before May 17, 2021.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R03-
OAR-2020-0703 at https://www.regulations.gov, or via email to 
talley.david@epa.gov. For comments submitted at Regulations.gov, follow 
the online instructions for submitting comments. Once submitted, 
comments cannot be edited or removed from Regulations.gov. For either 
manner of submission, 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. EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (i.e. on the web, cloud, or other file sharing 
system). For additional submission methods, please contact the person 
identified in the FOR FURTHER INFORMATION CONTACT section. For the full 
EPA public comment policy, information about CBI or multimedia 
submissions, and general guidance on making effective comments, please 
visit https://www.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Erin Trouba, Planning & Implementation 
Branch (3AD30), Air & Radiation Division, U.S. Environmental Protection 
Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103. 
The telephone number is (215) 814-2023. Ms. Trouba can also be reached 
via electronic mail at trouba.erin@epa.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. What action is EPA proposing?
II. Background and Requirements for Regional Haze Plans
    A. Regional Haze Background
    B. Roles of Agencies in Addressing Regional Haze
III. Requirements for Regional Haze Plans for the Second 
Implementation Period
    A. Identification of Class I Areas
    B. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the Uniform Rate of Progress (URP)
    C. Long-Term Strategy for Regional Haze
    D. Reasonable Progress Goals

[[Page 19794]]

    E. Monitoring Strategy and Other Implementation Plan 
Requirements
    F. Requirements for Periodic Reports Describing Progress Towards 
the Reasonable Progress Goals
    G. Requirements for State and Federal Land Manager Coordination
IV. EPA's Evaluation of the District's Regional Haze Submission for 
the Second Implementation Period
    A. Background on the District's First Implementation Period SIP 
Submission
    B. The District's Second Implementation Period SIP Submission 
and EPA Evaluation
    C. Identification of Class I Areas
    D. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the URP
    E. Long-Term Strategy for Regional Haze
    1. The District's Response to the Six MANE-VU Asks
    2. EPA's Evaluation of the District's Response to the Six MANE-
VU Asks and Compliance With 40 CFR 51.308(f)(2)(i)
    3. Additional Long-Term Strategy Requirements
    F. Reasonable Progress Goals
    G. Monitoring Strategy and Other Implementation Plan 
Requirements
    H. Requirements for Periodic Reports Describing Progress Towards 
the Reasonable Progress Goals
    I. Requirements for State and Federal Land Manager Coordination
V. Error Correction
    A. What is EPA's authority to correct errors in SIP rulemakings?
    B. What rule is EPA proposing to correct?
    C. What action is EPA proposing?
VI. Proposed Action
VII. Statutory and Executive Order Reviews

I. What action is EPA proposing?

    On November 8, 2019, DC DOEE submitted a revision to its SIP to 
address regional haze for the second implementation period (``DC DOEE 
2019 Regional Haze SIP submission''). DC DOEE made this SIP submission 
to satisfy the requirements of the CAA's regional haze program pursuant 
to CAA sections 169A and 169B and 40 CFR 51.308. EPA is proposing to 
find that the DC DOEE 2019 Regional Haze SIP submission meets the 
applicable statutory and regulatory requirements and thus proposes to 
approve the District's submission into its SIP.
    EPA is also proposing to correct an error in the citations of the 
regulatory provisions in our final rule (FRN) and identification of 
plan of the DC NOX RACT rule (February 24, 2020, 85 FR 
10295) according to our authority to make corrections to prior SIP 
actions under Section 110(k)(6) of the CAA.

II. Background and Requirements for Regional Haze Plans

A. Regional Haze Background

    In the 1977 CAA amendments, Congress created a program for 
protecting visibility in the nation's mandatory Class I Federal areas, 
which include certain national parks and wilderness areas.\1\ 42 U.S.C. 
7491. The CAA establishes as a national goal the ``prevention of any 
future, and the remedying of any existing, impairment of visibility in 
mandatory class I Federal areas which impairment results from manmade 
air pollution.'' 42 U.S.C. 7491(a)(1). The CAA further directs EPA to 
promulgate regulations to assure reasonable progress toward meeting 
this national goal. 42 U.S.C. 7491(a)(4). On December 2, 1980, EPA 
promulgated regulations to address visibility impairment in mandatory 
Class I Federal areas (hereinafter referred to as ``Class I areas'') 
that is ``reasonably attributable'' to a single source or small group 
of sources. 45 FR 80084. These regulations, codified at 40 CFR 51.300 
through 51.307, represented the first phase of EPA's efforts to address 
visibility impairment. In 1990, Congress added section 169B to the CAA 
to further address visibility impairment, specifically, impairment from 
regional haze. 42 U.S.C. 7492. EPA promulgated the RHR, codified at 40 
CFR 51.308,\2\ on July 1, 1999. 64 FR 35714. These regional haze 
regulations are a central component of EPA's comprehensive visibility 
protection program for Class I areas.
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    \1\ Areas statutorily designated as mandatory Class I Federal 
areas consist of national parks exceeding 6,000 acres, wilderness 
areas and national memorial parks exceeding 5,000 acres, and all 
international parks that were in existence on August 7, 1977. 42 
U.S.C. 7472(a). There are 156 mandatory Class I areas. The list of 
areas to which the requirements of the visibility protection program 
apply is in 40 CFR part 81, subpart D.
    \2\ In addition to the generally applicable regional haze 
provisions at 40 CFR 51.308, EPA also promulgated regulations 
specific to addressing regional haze visibility impairment in Class 
I areas on the Colorado Plateau at 40 CFR 51.309. The latter 
regulations are applicable only for specific jurisdictions' regional 
haze plans submitted no later than December 17, 2007, and thus are 
not relevant here.
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    Regional haze is visibility impairment that is produced by a 
multitude of sources and activities which are located across a broad 
geographic area and that emit pollutants that impair visibility. 
Visibility impairing pollutants include fine and coarse particulate 
matter (PM) (e.g., sulfates, nitrates, organic carbon, elemental 
carbon, and soil dust) and their precursors (e.g., sulfur dioxide 
(SO2), NOX, and, in some cases, volatile organic 
compounds (VOC) and ammonia (NH3)). Fine particle precursors 
react in the atmosphere to form fine particulate matter 
(PM2.5), which impairs visibility by scattering and 
absorbing light. Visibility impairment reduces the perception of 
clarity and color, as well as visible distance.\3\
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    \3\ There are several ways to measure the amount of visibility 
impairment, i.e., haze. One such measurement is the deciview, which 
is the principle metric used by the RHR. Under many circumstances, a 
change in one deciview will be perceived by the human eye to be the 
same on both clear and hazy days. The deciview is unitless. It is 
proportional to the logarithm of the atmospheric extinction of 
light, which is the perceived dimming of light due to its being 
scattered and absorbed as it passes through the atmosphere. 
Atmospheric light extinction (bext) is a metric used to 
for expressing visibility and is measured in inverse megameters (Mm-
1). The 2019 RHR Guidance offers the flexibility for the use of 
light extinction in certain cases. Light extinction can be simpler 
to use in calculations than deciviews, since it is not a logarithmic 
function. See, e.g., 2019 Guidance at 16, 19. The formula for the 
deciview is 10 ln (bext)/10 Mm-1). 40 CFR 51.301.
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    To address regional haze visibility impairment, the 1999 RHR 
established an iterative planning process that requires states in which 
Class I areas are located and states ``the emissions from which may 
reasonably be anticipated to cause or contribute to any impairment of 
visibility'' in a Class I area to periodically submit SIP revisions to 
address regional haze visibility impairment. 42 U.S.C. 7491(b)(2); 40 
CFR 51.308(b) and (f); see also 64 FR 35768 (July 1, 1999). Under the 
CAA, each SIP submission must contain ``a long-term (ten to fifteen 
years) strategy for making reasonable progress toward meeting the 
national goal,'' 42 U.S.C. 7491(b)(2)(B); the initial round of SIP 
submissions also had to address the statutory requirement that certain 
older, larger sources of visibility impairing pollutants install and 
operate the best available retrofit technology (BART). 42 U.S.C. 
7491(b)(2)(A); 40 CFR 51.308(d) and (e). States' first regional haze 
SIPs were due by December 17, 2007, 40 CFR 51.308(b), with subsequent 
SIP submissions containing revised long-term strategies originally due 
July 31, 2018, and every ten years thereafter. 64 FR 35768, July 1, 
1999. EPA established in the 1999 RHR that all states either have Class 
I areas within their borders or ``contain sources whose emissions are 
reasonably anticipated to contribute to regional haze in a Class I 
area;'' therefore, all states must submit regional haze SIPs.\4\ 64 FR 
35721, July 1, 1999.
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    \4\ In addition to each of the fifty states, EPA also concluded 
that the Virgin Islands and District of Columbia contain a Class I 
area and/or contain sources whose emissions are reasonably 
anticipated to contribute regional haze in a Class I area. See 40 
CFR 51.300(b) and (d)(3).
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    Much of the focus in the first implementation period of the 
regional haze program, which ran from 2007 through 2018, was on 
satisfying states' BART obligations. First implementation period SIPs 
were additionally required to contain long-term strategies for

[[Page 19795]]

making reasonable progress toward the national visibility goal. The 
core required elements for the first implementation period SIPs (other 
than BART) are laid out in 40 CFR 51.308(d). Those provisions required 
that states containing Class I areas establish reasonable progress 
goals (RPGs) that are measured in deciviews and reflect the visibility 
conditions at the end of the implementation period. The first planning 
period RPGs were required to provide for an improvement in visibility 
for the most impaired days over the period of the implementation plan 
and ensure no degradation in visibility for the least impaired days 
over the same period. In establishing the RPGs for any Class I area in 
a state, the state was required to consider four statutory factors: The 
costs of compliance, the time necessary for compliance, the energy and 
non-air quality environmental impacts of compliance, and the remaining 
useful life of any potentially affected sources. 42 U.S.C. 7491(g)(1); 
40 CFR 51.308(d)(1).
    States were also required to calculate baseline (using the five 
year period of 2000-2004) \5\ and natural visibility conditions (i.e., 
visibility conditions without anthropogenic visibility impairment) for 
each Class I area, and to calculate the linear rate of progress needed 
to attain natural visibility conditions, assuming a starting point of 
baseline visibility conditions in 2004 and ending with natural 
conditions in 2064. This linear interpolation is known as the uniform 
rate of progress (URP) and is used as a tracking metric to help states 
assess the amount of progress they are making towards the national 
visibility goal over time in each Class I area.\6\ 40 CFR 
51.308(d)(1)(i)(B) and (d)(2). The 1999 RHR also provided that States 
must submit long-term strategies that include the ``enforceable 
emissions limitations, compliance, schedules, and other measures as 
necessary to achieve the reasonable progress goals,'' id. at 40 CFR 
51.308(d)(3), and required that, in establishing their long-term 
strategies, states consult with other states that also contribute to 
visibility impairment in a Class I area and include all measures 
necessary to obtain their shares of the emission reductions needed to 
meet the RPGs. Id. at 40 CFR 51.308(d)(3)(i) and (ii). Section 
51.308(d) also contains seven additional factors states must consider 
in formulating their long-term strategies, id. at 40 CFR 
51.308(d)(3)(v), as well as provisions governing monitoring and other 
implementation plan requirements, id. at 40 CFR 51.308(d)(4). Finally, 
the 1999 RHR required states to submit periodic progress reports--SIP 
revisions due every five years that contain information on states' 
implementation of their regional haze plans and an assessment of 
whether anything additional is needed to make reasonable progress, see 
40 CFR 51.308(g) and (h)--and to consult with the Federal Land 
Manager(s) \7\ (FLMs) responsible for each Class I area according to 
the requirements in 42 U.S.C. 7491(d) and 40 CFR 51.308(i).
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    \5\ Additional information on the five-year average baseline 
calculation requirement in 40 CFR 51.308(f)(1)(i) is contained in: 
``Recommendation for the Use of Patched and Substituted Data and 
Clarification of Data Completeness for Tracking Visibility Progress 
for the Second Implementation Period of the Regional Haze Program.'' 
EPA Office of Air Quality Planning and Standards, Research Triangle 
Park (June 3, 2020). Available at: https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program.
    \6\ EPA established the URP framework in the 1999 RHR to provide 
``an equitable analytical approach'' to assessing the rate of 
visibility improvement at Class I areas across the country. The 
endpoint for the URP analysis was calculated based on the amount of 
visibility improvement that was anticipated to result from 
implementation of existing CAA programs over the period from the 
mid-1990s to approximately 2005. Assuming this rate of progress 
would continue into the future, EPA determined that natural 
visibility conditions would be reached in 2064. However, EPA did not 
establish 2064 as the year by which the national goal must be 
reached. 64 FR 35731-32, July 1, 1999. That is, the URP and the 2064 
date are not enforceable targets, but are rather tools that ``allow 
for analytical comparisons between the rate of progress that would 
be achieved by the state's chosen set of control measures and the 
URP.'' 82 FR 3084, January 10, 2017.
    \7\ EPA's regulations define ``Federal Land Manager'' as ``the 
Secretary of the department with authority over the Federal Class I 
area (or the Secretary's designee) or, with respect to Roosevelt-
Campobello International Park, the Chairman of the Roosevelt-
Campobello International Park Comission.'' 40 CFR 51.301.
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    On January 10, 2017, EPA promulgated revisions to the RHR that 
apply for the second and subsequent implementation periods. 82 FR 3078. 
The 2017 rule made several changes to the requirements for regional 
haze SIPs to clarify States' obligations and streamline certain 
regional haze requirements. The revisions to the regional haze program 
for the second and subsequent implementation periods focused on the 
requirement that States' SIPs contain long-term strategies for making 
reasonable progress towards the national visibility goal. The 
reasonable progress requirements as revised in the 2017 rule (referred 
to here as the 2017 RHR Revisions) are codified at 40 CFR 51.308(f). 
Among other changes relative to the first period requirements, the 2017 
RHR Revisions adjusted the deadline for States to submit their second-
implementation-period SIPs from July 31, 2018 to July 31, 2021, 
clarified the order of analysis and the relationship between RPGs and 
the long-term strategy, and focused on making visibility improvements 
on the days with the most anthropogenic visibility impairment, as 
opposed to the days with the most visibility impairment overall. EPA 
also revised requirements of the visibility protection program related 
to periodic progress reports and FLM consultation. The specific 
requirements applicable to second implementation period regional haze 
SIP submissions are addressed in detail below.
    EPA provided guidance to the States for their second implementation 
period SIP submissions in the preamble to the 2017 RHR Revisions as 
well as in subsequent, stand-alone guidance documents. In August 2019, 
EPA issued ``Guidance on Regional Haze State Implementation Plans for 
the Second Implementation Period'' (``2019 Guidance'').\8\ 
Additionally, EPA further clarified the recommended procedures for 
processing ambient visibility data and optionally adjusting the URP to 
account for international anthropogenic and prescribed fire impacts in 
two technical guidance documents: The December 2018 ``Technical 
Guidance on Tracking Visibility Progress for the Second Implementation 
Period of the Regional Haze Program'' \9\ (2018 Visibility Tracking 
Guidance), and the June 2020 ``Recommendation for the Use of Patched 
and Substituted Data and Clarification of Data Completeness for 
Tracking Visibility Progress for the Second Implementation Period of 
the Regional Haze Program'' and associated Technical Addendum.\10\
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    \8\ Guidance on Regional Haze State Implementation Plans for the 
Second Implementation Period. Available at: https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period EPA Office of Air Quality Planning and 
Standards, Research Triangle Park (August 20, 2019).
    \9\ Technical Guidance on Tracking Visibility Progress for the 
Second Implementation Period of the Regional Haze Program. Available 
at: https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional EPA Office 
of Air Quality Planning and Standards, Research Triangle Park. 
(December 20, 2018).
    \10\ Recommendation for the Use of Patched and Substituted Data 
and Clarification of Data Completeness for Tracking Visibility 
Progress for the Second Implementation Period of the Regional Haze 
Program. Available at: https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program, EPA Office of Air Quality Planning and Standards, 
Research Triangle Park (June 3, 2020).
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B. Roles of Agencies in Addressing Regional Haze

    Because the air pollutants and pollution affecting visibility in 
Class I

[[Page 19796]]

areas can be transported over long distances, successful implementation 
of the regional haze program requires long-term, regional coordination 
among multiple jurisdictions and agencies that have responsibility for 
Class I areas and the emissions that impact visibility in those areas. 
In order to address regional haze, states need to develop strategies in 
coordination with one another, considering the effect of emissions from 
one jurisdiction on the air quality in another. Five regional planning 
organizations (RPOs), which include representation from state and 
tribal governments, EPA, and FLMs, were developed in the lead-up to the 
first implementation period to address regional haze. RPOs evaluate 
technical information to better understand how emissions from State and 
Tribal land impact Class I areas across the country, pursue the 
development of regional strategies to reduce emissions of particulate 
matter and other pollutants leading to regional haze, and help states 
meet the consultation requirements of the RHR.
    The Mid-Atlantic/Northeast Visibility Union (MANE-VU), one of the 
five RPOs described above, is a collaborative effort of state 
governments, tribal governments, and various Federal agencies 
established to initiate and coordinate activities associated with the 
management of regional haze, visibility, and other air quality issues 
in the Mid-Atlantic and Northeast corridor of the United States. Member 
states and tribal governments (listed alphabetically) include: 
Connecticut, Delaware, the District of Columbia, Maine, Maryland, 
Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, 
Penobscot Indian Nation, Rhode Island, St. Regis Mohawk Tribe, and 
Vermont. The non-voting Federal partner members of MANE-VU are EPA, 
U.S. National Parks Service (NPS), U.S. Fish and Wildlife Service 
(FWS), and U.S. Forest Service (USFS).

III. Requirements for Regional Haze Plans for the Second Implementation 
Period \11\
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    \11\ Note that this section provides a narrative description of 
the RHR. The actual legal requirements against which SIP submissions 
for the second implementation period are evaluated are those 
contained in CAA sections 169A and 40 CFR 51.308(f).
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    Under the CAA and EPA's regulations, all 50 states, the District of 
Columbia, and the U.S. Virgin Islands are required to submit regional 
haze SIPs satisfying the applicable requirements for the second 
implementation period of the regional haze program by July 31, 2021. 
Each state's SIP must contain a long-term (ten to fifteen years) 
strategy for making reasonable progress toward meeting the national 
goal of remedying any existing and preventing any future anthropogenic 
visibility impairment in Class I areas. 42 U.S.C. 7491(b)(2)(B). To 
this end, 40 CFR 51.308(f) lays out the process by which states 
determine what constitutes their long-term strategies, with the order 
of the requirements in 40 CFR 51.308(f)(1) through (3) generally 
mirroring the order of the steps in the reasonable progress analysis 
\12\ and (f)(4) through (6) containing additional, related 
requirements. Broadly speaking, a state first must identify the Class I 
areas within the state and determine the Class I areas outside the 
state in which visibility may be affected by emissions from the state. 
These are the Class I areas that must be addressed in the state's long-
term strategy. See 40 CFR 51.308(f) introductory text and (f)(2). For 
each Class I area within its borders, a state must then calculate the 
baseline, current, and natural visibility conditions for that area, as 
well as the visibility improvement made to date and the URP. See 40 CFR 
51.308(f)(1). Each state having a Class I area and/or emissions that 
may affect visibility in a Class I area must then develop a long-term 
strategy that includes the enforceable emission limitations, compliance 
schedules, and other measures that are necessary to make reasonable 
progress in such areas. Reasonable progress is determined by applying 
the four factors in CAA section 169A(g)(1) to a set of sources of 
visibility-impairing pollutants the state has selected to assess for 
controls for the second implementation period. See 40 CFR 51.308(f)(2). 
After a state has developed its long-term strategy, including by 
determining what level of control for visibility-impacting sources 
represents reasonable progress, it then establishes RPGs for each Class 
I area within its borders by modeling the visibility impacts of all 
reasonable progress controls at the end of the second implementation 
period, i.e., in 2028, as well as the impacts of other requirements of 
the CAA. The RPGs include reasonable progress controls not only for 
sources in the state in which the Class I area is located, but also for 
sources in other states that contribute to visibility impairment in 
that area. The RPGs are then compared to the baseline visibility 
conditions and the uniform rate of progress to ensure that progress is 
being made towards the statutory goal of preventing any future and 
remedying any existing visibility impairment in Class I areas. Id. 40 
CFR 51.308(f)(3).
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    \12\ EPA explained in the 2017 RHR Revisions that we were 
adopting new regulatory language in 40 CFR 51.308(f) that, unlike 
the structure in 40 CFR 51.308(d), ``tracked the actual planning 
sequence.'' 82 FR 3091 (January 10, 2017).
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    In addition to satisfying the requirements at 40 CFR 51.308(f) 
related to reasonable progress, the SIP submissions due by July 31, 
2021, for the second implementation period must address the 
requirements in 40 CFR 51.308(g)(1) through (5) pertaining to periodic 
reports describing progress towards the RPGs, 40 CFR 51.308(f)(5), as 
well as requirements for FLM consultation that apply to all visibility 
protection SIPs and SIP revisions. 40 CFR 51.309(i). A state must 
submit its regional haze SIP and subsequent SIP revisions to EPA 
according to the requirements applicable to all SIP revisions under the 
CAA and EPA's regulations. See 42 U.S.C. 7491(b)(2); 7410(a). Upon EPA 
approval, a SIP is enforceable by the Agency and the public under the 
CAA. If EPA finds that a state fails to make a required SIP revision, 
or if EPA finds that a state's SIP is incomplete or if disapproves the 
SIP, the Agency must promulgate a federal implementation plan (FIP) 
that satisfies the applicable requirements. 42 U.S.C. 7410(c)(1).

A. Identification of Class I Areas

    The SIP revision submission due by July 31, 2021, ``must address 
regional haze in each mandatory Class I Federal area located within the 
State and in each mandatory Class I Federal area located outside the 
State that may be affected by emissions from within the State.'' 40 CFR 
51.308(f); see also 40 CFR 51.308(f)(2).\13\ Thus, the first step in 
developing a regional haze SIP is for a state to determine which Class 
I areas, in addition to those within its borders, ``may be affected'' 
by emissions from within the state. In the 1999 RHR, EPA determined 
that all states contribute to visibility impairment in at least one 
Class I area (64 FR 35720-22, July 1, 1999) and explained that the 
statute and regulations lay out an ``extremely low triggering 
threshold'' for determining ``whether States should be required to 
engage in air quality planning and analysis as a prerequisite to 
determining the need for control of emissions from sources within their 
State.'' Id. at 35721.
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    \13\ The RHR uses the phrase ``that may be affected by emissions 
from the State'' to implement CAA 169A(b)(2)'s requirement that a 
state ``the emissions from which may reasonably be anticipated to 
cause or contribute to any impairment of visibility'' submit a SIP.
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    A state must determine which Class I areas must be addressed by its 
SIP by evaluating the total emissions of

[[Page 19797]]

visibility impairing pollutants from all sources within the state. 
While the RHR does not require this assessment to be conducted in any 
particular manner, EPA's 2019 Guidance provides recommendations for how 
such an assessment might be accomplished, including by, where 
appropriate, using the determinations previously made for the first 
implementation period. 2019 Guidance at 8-9. As explained below, the 
determination of which Class I areas may be affected by a state's 
emissions is subject to the requirement in 40 CFR 51.308(f)(2)(iii) to 
``document the technical basis, including modeling, monitoring, cost, 
engineering, and emissions information, on which the State is relying 
to determine the emission reduction measures that are necessary to make 
reasonable progress in each mandatory Class I Federal area it 
affects.''

B. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the Uniform Rate of Progress (URP)

    As part of assessing whether a proposed SIP submission for the 
second implementation period is providing for reasonable progress 
towards the national visibility goal, the RHR contains requirements in 
40 CFR 51.308(f)(1) related to tracking visibility improvement over 
time. The requirements of this subsection apply only to states having 
Class I areas within their borders; the required calculations must be 
made for each such Class I area. EPA's 2018 Visibility Tracking 
Guidance \14\ provides recommendations to assist states in satisfying 
their obligations under 40 CFR 51.308(f)(1), specifically, in 
developing information on baseline, current, and natural visibility 
conditions, and in making optional adjustments to the URP to account 
for the impacts of international anthropogenic emissions. See 82 FR 
3103-05 (January 10, 2017).
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    \14\ The 2018 Visibility Tracking Guidance references and relies 
on parts of the 2003 Tracking Guidance: ``Guidance for Tracking 
Progress Under the Regional Haze Rule,'' available at: https://www.epa.gov/visibility/guidance-tracking-progress-under-regional-haze-rule.
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    The RHR requires tracking of visibility conditions on two sets of 
days: the clearest and the most impaired days. Visibility conditions 
for both sets of days are expressed as the average deciview index for 
the relevant five-year period (the period representing baseline or 
current visibility conditions). The RHR provides that the relevant sets 
of days for visibility tracking purposes are the 20% clearest (the 20% 
of monitored days in a calendar year with the lowest values of the 
deciview index) and 20% most impaired days (the 20% of monitored days 
in a calendar year with the highest amounts of anthropogenic visibility 
impairment).\15\ 40 CFR 51.301. A state must calculate visibility 
conditions for both the 20% clearest and 20% most impaired days for the 
baseline period of 2000-2004 and the most recent five-year period for 
which visibility monitoring data are available (representing current 
visibility conditions). 40 CFR 51.308(f)(1)(i) and (iii). States must 
also calculate natural visibility conditions for the clearest and most 
impaired days,\16\ by estimating the conditions that would exist on 
those two sets of days absent anthropogenic visibility impairment. 40 
CFR 51.308(f)(1)(ii). Using all these data, states must then calculate, 
for each Class I area, the amount of progress made since the baseline 
period (2000-2004) and how much improvement is left to achieve in order 
to reach natural visibility conditions.
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    \15\ This document also refers to the 20% clearest and 20% most 
anthropogenically impaired days as the ``clearest'' and ``most 
impaired'' or ``most anthropogenically impaired'' days, 
respectively.
    \16\ The RHR at 40 CFR 51.308(f)(1)(ii) contains an error 
related to the requirement for calculating two sets of natural 
conditions values. The rule says ``most impaired days or the 
clearest days'' where it should say ``most impaired days and 
clearest days.'' This is an error that was intended to be corrected 
in the 2017 RHR Revisions but did not get corrected in the final 
rule language. This is supported by the preamble text at 82 FR 3098, 
January 10, 2017: ``In the final version of 40 CFR 51.308(f)(1)(ii), 
an occurrence of ``or'' has been corrected to ``and'' to indicate 
that natural visibility conditions for both the most impaired days 
and the clearest days must be based on available monitoring 
information.''
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    Using the data for the set of most impaired days only, states must 
plot a line between visibility conditions in the baseline period and 
natural visibility conditions for each Class I area to determine the 
URP--the amount of visibility improvement, measured in deciviews, that 
would need to be achieved during each implementation period in order to 
achieve natural visibility conditions by the end of 2064. The URP is 
used in later steps of the reasonable progress analysis for 
informational purposes and to provide a non-enforceable benchmark 
against which to assess a Class I area's rate of visibility 
improvement.\17\ Additionally, in the 2017 RHR Revision, EPA provided 
states the option of proposing to adjust the end-point of the URP to 
account for impacts of anthropogenic sources outside the United States 
and/or impacts of certain types of wildland prescribed fires. These 
adjustments, which must be approved by EPA, are intended to avoid any 
perception that states should compensate for impacts from international 
anthropogenic sources and to give states the flexibility to determine 
that limiting the use of wildland-prescribed fire is not necessary for 
reasonable progress. 82 FR 3107 n.116 (January 10, 2017).
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    \17\ Being on or below the URP is not a ``safe harbor,'' i.e., 
achieving the URP does not mean that a Class I area is making 
``reasonable progress'' and does not relieve a state from using the 
four statutory factors to determine what level of control is needed 
to achieve such progress. See, e.g., 82 FR at 3093, January 10, 
2017.
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C. Long-Term Strategy for Regional Haze

    The core component of a regional haze SIP submission is a long-term 
strategy that addresses regional haze in each Class I area within a 
state's borders and each Class I area that may be affected by emissions 
from the state. The long-term strategy ``must include the enforceable 
emissions limitations, compliance schedules, and other measures that 
are necessary to make reasonable progress, as determined pursuant to 40 
CFR 51.308(f)(2)(i) through (iv).'' 40 CFR 51.308(f)(2). The amount of 
progress that is ``reasonable progress'' is determined by applying the 
four statutory factors in CAA section 169A(g)(1) in an evaluation of 
potential control options for sources of visibility impairing 
pollutants, which is referred to as a ``four-factor'' analysis. The 
outcome of that analysis is the level of control of emissions that a 
particular source or group of sources needs to achieve in order to make 
reasonable progress towards the national visibility goal. The RHR 
refers to the controls identified pursuant to a four-factor analysis as 
``emission reduction measures.'' See, e.g., 40 CFR 51.308(f)(2)(i). 
Such measures, along with any ``enforceable emissions limitations, 
compliance schedules, and other measures'' (i.e., any compliance tools) 
that are necessary to ensure that the level of control identified as 
``reasonable progress'' is in fact achieved, become part of a state's 
long-term strategy. 40 CFR 51.308(f)(2).
    Section 51.308(f)(2)(i) provides the requirements for the four-
factor analysis. The first step of this analysis entails selecting the 
sources to be evaluated for emission reduction measures; to this end, 
the RHR requires states to consider ``major and minor stationary 
sources or groups of sources, mobile sources, and area sources'' of 
visibility impairing pollutants to which the four statutory factors 
will be applied in an analysis of potential controls. 40 CFR 
51.308(f)(2)(i). While states have the option to analyze all sources, 
the 2019 Guidance explains that ``an analysis of control measures is 
not

[[Page 19798]]

required for every source in each implementation period,'' and that 
``[s]electing a set of sources for analysis of control measures in each 
implementation period is . . . consistent with the Regional Haze Rule, 
which sets up an iterative planning process and anticipates that a 
state may not need to analyze control measures for all its sources in a 
given SIP revision.'' 2019 Guidance at 9. The 2019 Guidance further 
provides recommendations and considerations for potential approaches to 
selecting sources for a four-factor analysis based on the fundamental 
premise that ``[a] state opting to select a set of its sources to 
analyze must reasonably choose factors [i.e., considerations for source 
selection] and apply them in a reasonable way given the statutory 
requirement to make reasonable progress towards natural visibility.'' 
2019 Guidance at 10. To this end, 40 CFR 51.308(f)(2)(i) requires that 
a state's SIP submission include ``a description of the criteria it 
used to determine which sources or groups of sources it evaluated.'' 
The technical basis for source selection, which may include methods for 
quantifying potential visibility impacts such as emissions divided by 
distance metrics, trajectory analyses, residence time analyses, and/or 
photochemical modeling, is also subject to 40 CFR 51.308(f)(2)(iii)'s 
documentation requirement.
    Once a state has selected the set of sources (if it has chosen not 
to analyze all sources of visibility impairment), the next step is to 
apply the four factors--``the costs of compliance, the time necessary 
for compliance, and the energy and quality environmental impacts of 
compliance, and the remaining useful life of any existing source 
subject to such requirements,'' 42 U.S.C. 7491A(g)(1)--to determine 
what level of emissions from those sources represents reasonable 
progress for the second implementation period.\18\ EPA has explained 
that the four-factor analysis is an assessment of potential emission 
reduction measures (i.e., control options) for sources; ``use of the 
terms `compliance' and `subject to such requirements' in section 
169A(g)(1) strongly indicates that Congress intended the relevant 
determination to be the requirements with which sources would have to 
comply in order to satisfy the CAA's reasonable progress mandate.'' 82 
FR 3091 (January 10, 2017). Thus, for each source it has selected for 
four-factor analysis,\19\ a state must consider a ``meaningful set'' of 
technically feasible control options for reducing emissions of 
visibility impairing pollutants. Id. at 3088. The 2019 Guidance 
provides that ``[a] state must reasonably pick and justify the measures 
that it will consider, recognizing that there is no statutory or 
regulatory requirement to consider all technically feasible measures or 
any particular measures. A range of technically feasible measures 
available to reduce emissions would be one way to justify a reasonable 
set.'' 2019 Guidance at 29.
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    \18\ The CAA provides that, ``[i]n determining reasonable 
progress there shall be taken into consideration'' the four 
statutory factors. 42 U.S.C. 7491(g)(1). However, in addition to 
four-factor analyses for selected sources, groups of sources, or 
source categories, a state may also consider additional emission 
reduction measures for inclusion in its long-term strategy, e.g., 
from other newly adopted or on-the-books and/or on-the-way rules and 
measures for sources not explicitly selected for four-factor 
analysis for the second planning period.
    \19\ ``Each source'' or ``particular source'' is used here as 
shorthand. While a source-specific analysis is one way of applying 
the four factors, neither the statute nor the RHR requires states to 
evaluate individual sources. Rather, states have ``the flexibility 
to conduct four-factor analyses for specific sources, groups of 
sources or even entire source categories, depending on state policy 
preferences and the specific circumstances of each state.'' 82 FR 
3088, January 10, 2017.
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    After identifying a reasonable set of control options for the 
sources it has selected, a state then collects information on the four 
factors with regard to each control option identified; this information 
will be considered when weighing the factors and selecting the control 
option that represents reasonable progress. EPA has also explained 
that, in addition to the four statutory factors, states have 
flexibility under the CAA and RHR to reasonably consider visibility 
benefits as an optional fifth factor alongside the four statutory 
factors.\20\ Here, again, the 2019 Guidance provides recommendations 
for the types of information that can be used to characterize the four 
factors (with or without visibility), as well as ways in which states 
might reasonably consider and balance that information to determine 
which of the potential control options is necessary to make reasonable 
progress. See 2019 Guidance at 30-36. While states have discretion to 
reasonably weigh the factors and to determine what level of control is 
needed, 40 CFR 51.308(f)(2)(i) provides that a state ``must include in 
its implementation plan a description of . . . how the four factors 
were taken into consideration in selecting the measure for inclusion in 
its long-term strategy.'' \21\
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    \20\ See, e.g., Responses to Comments on Protection of 
Visibility: Amendments to Requirements for State Plans; Proposed 
Rule (81 FR 26942, May 4, 2016), Docket Number EPA-HQ-OAR-2015-0531, 
U.S. Environmental Protection Agency at 186; 2019 Guidance at 36-37.
    \21\ This requirement extends to consideration of visibility as 
an optional fifth factor; because visibility is not explicitly 
enumerated as a potential factor in the RHR it is also not 
explicitly mentioned in 40 CFR 51.308(f)(2)(i).
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    As explained above, 40 CFR 51.308(f)(2)(i) requires states to 
determine the emission reduction measures for sources that are 
necessary to make reasonable progress by considering the four factors. 
Section 51.308(f)(2) in turn requires that a state's long-term 
strategy, which becomes part of its SIP, include ``the enforceable 
emissions limitations, compliance schedules, and other measures'' that 
are necessary to ensure that the level of control identified pursuant 
to the four-factor analysis, i.e., the amount of progress that is 
``reasonable progress,'' is achieved. That is, a state must include in 
its SIP any emission limitations and other compliances measures (e.g., 
compliance schedules and monitoring, reporting, and recordkeeping 
requirements) that are needed to ensure that a source in fact achieves 
and continues to achieve the level of emissions control that resulted 
from application of the four factors.
    As with source selection, the characterization of information on 
each of the factors is also subject to the documentation requirement in 
40 CFR 51.308(f)(2)(iii). The reasonable progress analysis, including 
source selection, information gathering, characterization of the four 
statutory factors (and potentially visibility), balancing of the four 
factors, and selection of the emission reduction measures that 
represent reasonable progress, is a technically complex exercise, but 
also a flexible one that provides states with bounded discretion to 
design and implement approaches appropriate to their circumstances. 
Given this flexibility, 40 CFR 51.308(f)(2)(iii) plays an important 
function in requiring a state to document the technical basis for its 
decision making so that the public and EPA can comprehend and evaluate 
the information and analysis the state relied upon to determine what 
emission reduction measures must be in place to make reasonable 
progress. The technical documentation must include the modeling, 
monitoring, cost, engineering, and emissions information on which the 
state relied to determine the measures necessary to make reasonable 
progress. This documentation requirement can be met through the 
provision of and reliance on technical analyses developed through a 
regional planning process, so long as that process and its

[[Page 19799]]

output has been approved by all state participants.
    The four statutory factors (and potentially visibility) are used to 
determine what emission reduction measures for selected sources must be 
included in a state's long-term strategy for making reasonable 
progress. Additionally, the RHR at 40 CFR 51.308(f)(2)(iv) separately 
provides five additional factors \22\ that states must consider in 
developing their long-term strategies, which we paraphrase: (1) 
Emission reductions due to ongoing air pollution control programs (2) 
measures to reduce the impacts of construction activities; (3) source 
retirement and replacement schedules; (4) basic smoke management 
practices; and (5) the anticipated net effect on visibility. EPA has 
explained that a state may satisfy this requirement by considering 
these additional factors in the process of selecting sources for four-
factor analysis, when performing that analysis, or both, and that not 
every one of the additional factors needs to be considered at the same 
stage of the process. See 2019 Guidance at 21.
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    \22\ The five additional factors for consideration in 40 CFR 
51.308(f)(2)(iv) are distinct from the four factors listed in CAA 
section 169A(g)(1) and 40 CFR 51.308(f)(2)(i) that states must 
consider and apply to sources in determining reasonable progress.
---------------------------------------------------------------------------

    Because the air pollution that causes regional haze crosses state 
boundaries, 40 CFR 51.308(f)(2)(ii) requires a state to consult with 
other states that also have emissions that are reasonably anticipated 
to contribute to visibility impairment in a given Class I area. The 
purpose of consultation is for each state that impacts visibility in an 
area to share whatever technical information, analyses, and control 
determinations may be necessary to develop coordinated emission 
management strategies. This coordination may be managed through inter- 
and intra-RPO consultation and the development of regional emissions 
strategies; additional consultations between states outside of RPO 
processes may also occur. While there is no requirement that a state 
include in its long-term strategy the emission reduction measures 
identified by other states, the RHR does require that a state at least 
consider such measures for its own sources. 40 CFR 51.308(f)(2). If a 
state, pursuant to consultation, agrees that certain measures (e.g., a 
certain emission limitation) are necessary to make reasonable progress 
at a Class I area, it must include those measures in its SIP. 40 CFR 
51.308(f)(2)(ii)(A). However, if a state has been asked to consider or 
adopt certain emission reduction measures, but ultimately determines 
those measures are not necessary to make reasonable progress, that 
state must document in its SIP the actions taken to resolve the 
disagreement. 40 CFR 51.308(f)(2)(ii)(C). EPA will consider the 
technical information and explanations presented by the submitting 
state and the state with which it disagrees when considering whether to 
approve the state's SIP. Id.; 2019 Guidance at 53. Under all 
circumstances, a state must document in its SIP submission all 
substantive consultations with other contributing states. 40 CFR 
51.308(f)(2)(ii)(C).

D. Reasonable Progress Goals

    Reasonable progress goals ``measure the progress that is projected 
to be achieved by the control measures states have determined are 
necessary to make reasonable progress based on a four-factor 
analysis,'' 82 FR at 3091, January 10, 2017; their primary purpose is 
to assist the public and EPA in assessing the reasonableness of states' 
long-term strategies for making reasonable progress towards the 
national visibility goal. See 40 CFR 51.308(f)(3)(iii) through (iv). 
States in which Class I areas are located must establish two RPGs, both 
in deciviews--one representing visibility conditions on the clearest 
days and one representing visibility on the most anthropogenically 
impaired days--for each such area within their borders. 40 CFR 
51.308(f)(3)(i). The two RPGs are intended to reflect the projected 
impacts, on the two sets of days, of the measures the state with the 
Class I area, as well as all other contributing states, have included 
in their long-term strategies for the second implementation period.\23\ 
The RPGs also account for the projected impacts of implementing other 
CAA requirements, including non-SIP based requirements. For this 
implementation period, the RPGs are set for 2028. Reasonable progress 
goals are not enforceable targets, 40 CFR 51.308(f)(3)(iii); rather, 
they ``provide a way for the states to check the projected outcome of 
the [long-term strategy] against the goals for visibility 
improvement.'' 2019 Guidance at 46. While states are not legally 
obligated to achieve the visibility conditions described in their RPGs, 
40 CFR 51.308(f)(3)(i) requires that ``[t]he long-term strategy and the 
reasonable progress goals must provide for an improvement in visibility 
for the most impaired days since the baseline period and ensure no 
degradation in visibility for the clearest days since the baseline 
period.'' Thus, states are required to have emission reduction measures 
in their long-term strategies that are projected to achieve visibility 
on the most impaired days that is better than the baseline period, and 
shows no degradation on the clearest days compared to the clearest days 
from the baseline period. The baseline period for the purpose of this 
comparison is the baseline visibility condition--the annual average 
visibility condition for the period 2000-2004. See 40 CFR 
51.308(f)(1)(i), 82 FR 3097-98 (January 10, 2017).
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    \23\ RPGs are intended to reflect, among other things, the 
projected impacts of the measures the states include in their long-
term strategies. However, due to the timing of multiple state 
analyses, determination of the final set of state long-term 
strategies, and other on-going emissions changes, a particular 
states' RPGs may not reflect all control measures and emissions 
reductions that are expected to occur by the end of the 
implementation period. The statute and rule address this practical 
challenge by requiring subsequent SIP submittals (every ten years), 
and periodic progress reports (due five years after each regional 
haze SIP).
---------------------------------------------------------------------------

    So that RPGs may also serve as a metric for assessing the amount of 
progress a state is making towards the national visibility goal, the 
RHR requires states with Class I areas to compare the 2028 RPG for the 
most impaired days to the corresponding point on the URP line 
(representing visibility conditions in 2028 if visibility were to 
improve at a linear rate from conditions in the baseline period of 
2000-2004 to natural visibility conditions in 2064). If the most 
impaired days RPG in 2028 is above the URP (i.e., if visibility 
conditions are improving more slowly than the rate described by the 
URP), each contributing state must demonstrate, based on the four-
factor analysis required under 40 CFR 51.308(f)(2)(i), that no 
additional emission reduction measures would be reasonable to include 
in its long-term strategy. 40 CFR 51.308(f)(3)(ii). To this end, 40 CFR 
51.308(f)(3)(ii) requires that each state contributing to visibility 
impairment in a Class I area that is projected to improve more slowly 
than the URP provide ``a robust demonstration, including documenting 
the criteria used to determine which sources or groups [of] sources 
were evaluated and how the four factors required by paragraph (f)(2)(i) 
were taken into consideration in selecting the measures for inclusion 
in its long-term strategy.'' The 2019 Guidance provides suggestions 
about how such a ``robust demonstration'' might be conducted. See 2019 
Guidance at 50-51.
    The 2017 RHR and 2019 Guidance also explain that projecting an RPG 
that is on or below the URP based on only on-the-books and/or on-the-
way control

[[Page 19800]]

measures (i.e., control measures already required or anticipated before 
the four-factor analysis is conducted) is not a ``safe harbor'' from 
the CAA's and RHR's requirement that all states must conduct a four-
factor analysis to determine what emission reduction measures 
constitute reasonable progress. See 82 FR 3078 at 3093, 3099-3100, 
January 10, 2017; 2019 Guidance at 22.

E. Monitoring Strategy and Other Implementation Plan Requirements

    Section 51.308(f)(6) requires states to have certain strategies and 
elements in place for assessing and reporting on visibility. Individual 
requirements under this subsection apply either to states with Class I 
areas within their borders, states with no Class I areas but that are 
reasonably anticipated to cause or contribute to visibility impairment 
in any Class I area, or both. A state with Class I areas within its 
borders must submit with its SIP revision a monitoring strategy for 
measuring, characterizing, and reporting regional haze visibility 
impairment that is representative of all Class I areas within the 
state. SIP revisions for such states must also provide for the 
establishment of any additional monitoring sites or equipment needed to 
assess visibility conditions in Class I areas, as well as reporting of 
all visibility monitoring data to EPA at least annually. Compliance 
with the monitoring strategy requirement may be met through a state's 
participation in the Interagency Monitoring of Protected Visual 
Environments (IMPROVE) monitoring network, which may be used to measure 
visibility impairment caused by air pollution at the 156 Class I areas 
covered by the visibility program. 40 CFR 51.308(f)(6) introductory 
text and (f)(6)(i) and (iv). The IMPROVE monitor data is used to 
determine the 20 percent most anthropogenically impaired and 20 percent 
clearest sets of days every year at each Class I area and tracks 
visibility impairment over time.
    All states' SIPs must provide for procedures by which monitoring 
data and other information are used to determine the contribution of 
emissions from within the state to regional haze visibility impairment 
in affected Class I areas. 40 CFR 51.308(f)(6)(ii) and (iii). Section 
51.308(f)(6)(v) further requires that all states' SIPs provide for a 
statewide inventory of emissions of pollutants that are reasonably 
anticipated to cause or contribute to visibility impairment in any 
Class I area; the inventory must include emissions for the most recent 
year for which data are available and estimates of future projected 
emissions. States must also include commitments to update their 
inventories periodically. The inventories themselves do not need to be 
included as elements in the SIP and are not subject to EPA review as 
part of the Agency's evaluation of a SIP revision.\24\ All states' SIPs 
must also provide for any other elements, including reporting, 
recordkeeping, and other measures, that are necessary for states to 
assess and report on visibility. 40 CFR 51.308(f)(6)(vi). Per the 2019 
Guidance, a state may note in its regional haze SIP that its compliance 
with the Air Emissions Reporting Rule (AERR) in 40 CFR part 51, subpart 
A, satisfies the requirement to provide for an emissions inventory for 
the most recent year for which data are available. To satisfy the 
requirement to provide estimates of future projected emissions, a state 
may explain in its SIP how projected emissions were developed for use 
in establishing RPGs for its own and nearby Class I areas.\25\
---------------------------------------------------------------------------

    \24\ See section ``Step 8: Additional requirements for regional 
haze SIPs'' in 2019 Regional Haze Guidance at 55.
    \25\ Id.
---------------------------------------------------------------------------

    Separate from the requirements related to monitoring for regional 
haze purposes under 40 CFR 51.308(f)(6), the RHR also contains a 
requirement at 40 CFR 51.308(f)(4) related to any additional monitoring 
that may be needed to address visibility impairment in Class I areas 
from a single source or a small group of sources. This is called 
``reasonably attributable visibility impairment.'' \26\ Under this 
provision, if EPA or the FLM of an affected Class I area has advised a 
state that additional monitoring is needed to assess reasonably 
attributable visibility impairment, the state must include in its SIP 
revision for the second implementation period an appropriate strategy 
for evaluating such impairment.
---------------------------------------------------------------------------

    \26\ EPA's visibility protection regulations define ``reasonably 
attributable visibility impairment'' as ``visibility impairment that 
is caused by the emission of air pollutants from one, or a small 
number of sources.'' 40 CFR 51.301.
---------------------------------------------------------------------------

F. Requirements for Periodic Reports Describing Progress Towards the 
Reasonable Progress Goals

    Section 51.308(f)(5) requires a state's regional haze SIP revision 
to address the requirements of 40 CFR 51.308(g)(1) through (5) so that 
the plan revision due in 2021 will serve also as a progress report 
addressing the period since submission of the progress report for the 
first implementation period. The regional haze progress report 
requirement is designed to inform the public and EPA about a state's 
implementation of its existing long-term strategy and whether such 
implementation is in fact resulting in the expected visibility 
improvement. See 81 FR 26942, 26950 (May 4, 2016), 82 FR 3119, January 
10, 2017. To this end, every state's SIP revision for the second 
implementation period is required to describe the status of 
implementation of all measures included in the state's long-term 
strategy, including BART and reasonable progress emission reduction 
measures from the first implementation period, and the resulting 
emissions reductions. 40 CFR 51.308(g)(1) and (2).
    A core component of the progress report requirements is an 
assessment of changes in visibility conditions on the clearest and most 
impaired days. Section 51.308(g)(3) requires states with Class I areas 
within their borders to first determine current visibility conditions 
for each area, 40 CFR 51.308(g)(3)(i), and then to calculate the 
difference between those current conditions and baseline (2000-2004) 
visibility conditions in order to assess progress made to date. See 40 
CFR 51.308(g)(3)(ii). For the purposes of 40 CFR 51.308(f)(5) and 
(g)(3)(iii) provides that the relevant period for assessing changes in 
visibility is the period since the most recent progress report. EPA 
interprets this period as starting from the period that represented 
``current visibility conditions'' in the first implementation period 
progress report. Since different states submitted their first 
implementation period progress reports at different times, the period 
reflecting ``current visibility conditions'' referenced in each state's 
progress report will vary.
    Similarly, the relevant period for the purpose of 40 CFR 
51.308(g)(4)'s analysis of emissions of visibility impairing pollutants 
starts with the period that represented ``current visibility 
conditions'' in the progress report for the first implementation period 
and runs through ``current conditions'' for the second implementation 
period. This provision requires an analysis tracking the change in 
emissions of pollutants contributing to visibility impairment from all 
sources and activities within the state; changes should be identified 
by (i.e., attributed to) type of source(s) or activity(ies). Section 
51.308(g)(5) also addresses changes in emissions since the period 
addressed by the previous progress report and requires states' SIP 
revisions to include an assessment of any significant changes in 
anthropogenic emissions within or outside the state. This assessment 
must include an explanation of whether these changes in emissions were 
anticipated and whether

[[Page 19801]]

they have limited or impeded progress in reducing emissions and 
improving visibility relative to what the state projected based on its 
long-term strategy for the first implementation period.

G. Requirements for State and Federal Land Manager Coordination

    Clean Air Act section 169A(d) requires that before a state holds a 
public hearing on a proposed regional haze SIP revision, it must 
consult with the appropriate FLM or FLMs; pursuant to that 
consultation, the state must include a summary of the FLMs' conclusions 
and recommendations in the notification to the public. Consistent with 
this statutory requirement, the RHR also requires that states ``provide 
the [FLM] with an opportunity for consultation, in person and at a 
point early enough in the State's policy analyses of its long-term 
strategy emission reduction obligation so that information and 
recommendations provided by the [FLM] can meaningfully inform the 
State's decisions on the long-term strategy.'' 40 CFR 51.308(i)(2). 
Consultation that occurs 120 days prior to any public hearing or public 
comment opportunity will be deemed ``early enough,'' but the RHR 
provides that in any event the opportunity for consultation must be 
provided at least 60 days before a public hearing or comment 
opportunity. This consultation must include the opportunity for the 
FLMs to discuss their assessment of visibility impairment in any Class 
I area and their recommendations on the development and implementation 
of strategies to address such impairment. 40 CFR 51.308(i)(2). In order 
for EPA to evaluate whether FLM consultation meeting the requirements 
of the RHR has occurred, the SIP submission should include 
documentation of the timing and content of such consultation. The SIP 
revision submitted to EPA must also describe how the state addressed 
any comments provided by the FLMs. 40 CFR 51.308(i)(3). Finally, a SIP 
revision must provide procedures for continuing consultation between 
the state and FLMs regarding the state's visibility protection program, 
including development and review of SIP revisions, five-year progress 
reports, and the implementation of other programs having the potential 
to contribute to impairment of visibility in Class I areas. 40 CFR 
51.308(i)(4).

IV. EPA's Evaluation of the District's Regional Haze Submission for the 
Second Implementation Period

A. Background on the District's First Implementation Period SIP 
Submission

    The District submitted its regional haze SIP for the first 
implementation period to EPA on October 27, 2011. EPA published a final 
rule fully approving the first DC regional haze SIP submission on 
February 2, 2012 (77 FR 5191). The requirements for regional haze SIPs 
for the first implementation period are contained in 40 CFR 51.308(d) 
and (e). 40 CFR 51.308(b). The District has no Class I areas within its 
borders. In the first implementation period, MANE-VU used two criteria 
to determine whether certain SO2 emissions from individual 
jurisdictions within the region affected visibility in any Class I 
areas: Contribution of greater than 0.1 microgram per cubic meter 
([micro]g/m\3\) or two percent of sulfate emission contribution. 77 FR 
70929, 70935 (November 16, 2011). The District relied on MANE-VU 
contribution assessment modeling to assert that emissions from the 
District did not meet either of these criteria. Regardless, EPA 
explained that ``the District . . . is responsible for developing a 
regional haze SIP that describes its long-term emission strategy, its 
role in the consultation processes, and how the SIP meets the other 
requirements in EPA's regional haze regulations.'' Id. Finding the 
District's SIP submission met the applicable requirements of 40 CFR 
51.308(d) and (e), EPA approved its plan for the first implementation 
period. Pursuant to 40 CFR 51.308(g), the District was also responsible 
for submitting a five-year progress report as a SIP revision for the 
first implementation period, which it did on March 2, 2016. EPA 
approved the progress report into the DC SIP on August 10, 2017 (82 FR 
37305).

B. The District's Second Implementation Period SIP Submission and EPA 
Evaluation

    In accordance with CAA sections 169A and the RHR at 40 CFR 
51.308(f), on November 8, 2019, DC DOEE submitted a revision to the DC 
SIP to address the jurisdiction's regional haze obligations for the 
second implementation period, which runs through 2028. The District 
made its 2019 Regional Haze SIP submission available for public comment 
on August 30, 2019 and held a hearing on September 30, 2019. No public 
comments were received.
    The following sections describe the District's SIP submission, 
including the analyses conducted by MANE-VU and the District's 
determinations based on those analyses, the District's assessment of 
progress made since the first implementation period in reducing 
emissions of visibility impairing pollutants, and the visibility 
improvement progress at nearby Class I areas. This document also 
contains EPA's evaluation of the District's submission against the 
requirements of the CAA and RHR for the second implementation period of 
the regional haze program.

C. Identification of Class I Areas

    Section 169(A)(b)(2) of the CAA requires each state in which any 
Class I area is located or ``the emissions from which may reasonably be 
anticipated to cause or contribute to any impairment of visibility'' in 
a Class I area to have a plan for making reasonable progress toward the 
national visibility goal. The RHR incorporates this statutory 
requirement at 40 CFR 51.308(f) introductory text, which provides that 
each state's plan ``must address regional haze in each mandatory Class 
I Federal area located within the State and in each mandatory Class I 
Federal area located outside the State that may be affected by 
emissions from within the State,'' and (f)(2), which requires each 
state's plan to include a long-term strategy that addresses regional 
haze in such Class I areas.
    EPA explained in the 1999 RHR preamble that the CAA section 
169A(b)(2) requirement that states submit SIPs to address visibility 
impairment establishes ``an `extremely low triggering threshold' in 
determining which States should submit SIPs for regional haze.'' 64 FR 
35721, July 1, 1999. In concluding that each of the contiguous 48 
states and the District of Columbia meet this threshold,\27\ EPA relied 
on ``a large body of evidence demonstrat[ing] that long-range transport 
of fine PM contributes to regional haze,'' id., including modeling 
studies that ``preliminarily demonstrated that each State not having a 
Class I area had emissions contributing to impairment in at least one 
downwind Class I area.'' Id. at 35722. In addition to the technical 
evidence supporting a conclusion that each state contributes to 
existing

[[Page 19802]]

visibility impairment, EPA also explained that the second half of the 
national visibility goal--preventing future visibility impairment--
requires having a framework in place to address future growth in 
visibility-impairing emissions and makes it inappropriate to 
``establish criteria for excluding States or geographic areas from 
consideration as potential contributors to regional haze visibility 
impairment.'' Id. at 35721. Thus, EPA concluded that the agency's 
``statutory authority and the scientific evidence are sufficient to 
require all States to develop regional haze SIPs to ensure the 
prevention of any future impairment of visibility, and to conduct 
further analyses to determine whether additional control measures are 
needed to ensure reasonable progress in remedying existing impairment 
in downwind Class I areas.'' Id. at 35722. EPA's 2017 revisions to the 
RHR did not disturb this conclusion. See 82 FR 3094, January 10, 2017.
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    \27\ EPA determined that ``there is more than sufficient 
evidence to support our conclusion that emissions from each of the 
48 contiguous states and the District of Columba may reasonably be 
anticipated to cause or contribute to visibility impairment in a 
Class I area.'' 64 FR 35721, July 1, 1999. Hawaii, Alaska, and the 
U.S. Virgin Islands must also submit regional haze SIPs because they 
contain Class I areas.
---------------------------------------------------------------------------

    For the second implementation period, MANE-VU performed technical 
analyses to help inform source and state-level contributions to 
visibility impairment and the need for interstate consultation.\28\ 
MANE-VU used the results of these analyses to determine which states' 
emissions ``have a high likelihood of affecting visibility in MANE-VU's 
Class I areas.'' \29\ The MANE-VU analyses used a combination of data 
analysis techniques, including emissions data, distance from Class I 
areas, wind trajectories, and CALPUFF dispersion modeling. Many of the 
analyses focused only on SO2 emissions and resultant 
particulate sulfate contributions to visibility impairment, while 
others also incorporated NOX emissions to estimate 
particulate nitrate contributions.
---------------------------------------------------------------------------

    \28\ The technical analysis performed by MANE-VU, including the 
contribution assessment methodologies for MANE-VU Class I areas, is 
summarized in appendix 1 of the DC DOEE 2019 Regional Haze SIP 
submission, ``Selection of States for MANE-VU Regional Haze 
Consultation (2018).''
    \29\ Id.
---------------------------------------------------------------------------

    One MANE-VU analysis used for contribution assessment was CALPUFF 
air dispersion modeling. The CALPUFF model simulated sulfate and 
nitrate formation and transport in MANE-VU and nearby regions from 
large electric generating units (EGU) point sources and other large 
industrial and institutional sources in the eastern and central United 
States. The CALPUFF modeling run included sources selected using 
emissions divided by distance, or ``Q/d'' analysis. The CALPUFF 
modeling summary report included the top 10 most impacting EGUs and the 
top 5 most impacting industrial sources for each Class I area and 
compiled those results into a ranked list of the most impacting EGUs 
and industrial sources at MANE-VU Class I areas.\30\ Due to a lack of 
large EGUs or industrial sources, no District emissions were included 
in the MANE-VU CALPUFF modeling.\31\
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    \30\ See Tables 34 and 35 of appendix 4 of the DC DOEE 2019 
Regional Haze SIP submission, ``2016 MANE-VU Source Contribution 
Modeling Report--CALPUFF Modeling of Large Electrical Generating 
Units and Industrial Sources (MANE-VU, April 2017).''
    \31\ See appendix 4 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    The other MANE-VU analysis used a meteorologically weighted Q/d 
calculation.\32\ The variable ``Q'' is the quantity of cumulative 
SO2 emissions from a source or a state, which is divided by 
the variable ``d,'' which is the distance of the source or state to the 
IMPROVE monitor receptor at a Class I area. The result is then 
multiplied by a constant (Ci), which is determined based on 
the prevailing wind patterns. MANE-VU selected a meteorologically 
weighted Q/d analysis as an inexpensive initial screening tool that 
could easily be repeated to determine which states, sectors, or sources 
have a larger relative impact and warrant further analysis. MANE-VU's 
analysis estimated the District's maximum sulfate contribution at 0.13% 
at any Class I area based on the maximum daily impact. The largest 
impacts from District SO2 emissions were to Brigantine 
Wilderness and Shenandoah National Park. The MANE-VU Q/d analysis was 
further extended to account for nitrate contributions from 
NOX emissions. Nitrate impacts were not originally estimated 
using Q/d, but MANE-VU wanted to include an approximation of nitrate 
impacts from area and mobile sources. MANE-VU developed a ratio of 
nitrate to sulfate impacts based on the previously described CALPUFF 
modeling and applied those to the sulfate Q/d results. Several states, 
including the District, did not have CALPUFF nitrate to sulfate ratio 
results because there were no point sources modeled with CALPUFF. For 
the District, MANE-VU developed a surrogate ratio from the Maryland 
CALPUFF results.
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    \32\ The methodology used by MANE-VU for the meteorological 
weighted Q/d analysis can be found in appendix 3 of the DC DOEE 2019 
Regional Haze SIP submission, ``MANE-VU Updated Q/d*C Contribution 
Assessment.''
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    In order to develop a final set of contribution estimates, MANE-VU 
weighted the results from both the Q/d and CALPUFF analyses. However, 
only Q/d results were used for the District, since there were no 
CALPUFF results for the District. The MANE-VU mass-weighted sulfate and 
nitrate contribution results were reported for the MANE-VU Class I 
areas (the Q/d summary report included results for several non-MANE-VU 
areas as well). The largest District mass-weighted sulfate and nitrate 
contribution to any Class I area was 0.2% to Brigantine Wilderness. 
Based on the results of the MANE-VU screening analyses, the District 
concludes in its regional haze submission that it is ``not `reasonably 
anticipated to contribute to visibility impairment' in any Class I 
Federal area.'' \33\
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    \33\ Section 2.4.3 of the DC DOEE 2019 Regional Haze SIP 
submission at 9.
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    As explained above, EPA concluded in the 1999 RHR that ``all 
[s]tates [including the District of Columbia] contain sources whose 
emissions are reasonably anticipated to contribute to regional haze in 
a Class I area,'' 64 FR 35721, July 1, 1999 and this determination was 
not changed in the 2017 RHR. Critically, the statute and regulation 
both require that the cause-or-contribute assessment consider all 
emissions of visibility-impairing pollutants from a state, as opposed 
to emissions of a particular pollutant or emissions from a certain set 
of sources. Consistent with these requirements, the 2019 Guidance makes 
it clear that ``all types of anthropogenic sources are to be included 
in the determination'' of whether a state's emissions are reasonably 
anticipated to result in any visibility impairment. 2019 Guidance at 8.
    The screening analyses on which MANE-VU relied are useful for 
certain purposes. MANE-VU used the technical analysis information to 
rank the largest contributing states to sulfate and nitrate impairment 
in five Class I areas within MANE-VU states and three additional, 
nearby Class I areas.\34\ The rankings were used to determine upwind 
states that were deemed important to include in state-to-state 
consultation (based on an identified impact screening threshold), and 
large individual source impacts were used to target MANE-VU control 
analysis ``Asks'' of states and sources both within and upwind of MANE-
VU.\35\ EPA finds the nature of

[[Page 19803]]

the analyses appropriate to make those types of conclusions. The 
District has participated in the MANE-VU visibility analysis and has 
provided information in its SIP submission on the magnitude of 
visibility impacts from certain District emissions on nearby Class I 
areas. However, the analyses did not account for all emissions and all 
components of visibility impairment (e.g. primary PM emissions, and 
impairment from fine PM, elemental carbon, and organic carbon). In 
addition, a Q/d analysis with a relatively simplistic accounting for 
wind trajectories and CALPUFF applied to major industrial sources of 
SO2 and NOX are not scientifically rigorous tools 
capable of ruling out a contribution to visibility impairment from all 
emissions in a state. This is particularly true for the District since 
the MANE-VU CALPUFF modeling did not include any District sources and 
because the nitrate impacts used in the Q/d analysis were derived from 
another state's ratio of nitrate to sulfate impacts. EPA does agree 
that the contribution to visibility impairment from District emissions 
at all nearby Class I areas is relatively small, and in fact may be 
amongst the smallest impacts to visibility impairment from the MANE-VU 
states. However, based on the information presented in the District's 
submission, there is not sufficient evidence for EPA to either agree or 
disagree with the conclusion that emissions from the District are not 
reasonably anticipated to cause or contribute to any impairment of 
visibility at any Class I area.
---------------------------------------------------------------------------

    \34\ The Class I areas analyzed were Acadia National Park in 
Maine, Brigantine Wilderness in New Jersey, Great Gulf Wilderness in 
New Hampshire, Lye Brook Wilderness in Vermont, Moosehorn Wilderness 
in Maine, Shenandoah National Park in Virginia, James River Face 
Wilderness in Virginia, and Dolly Sods/Otter Creek Wildernesses in 
West Virginia.
    \35\ The MANE-VU consultation report (Appendix 7 of the DC DOEE 
2019 Regional Haze SIP submission) explains that ``[t]he objective 
of this technical work was to identify states and sources from which 
MANE-VU will pursue further analysis. This screening was intended to 
identify which states to invite to consultation, not a definitive 
list of which states are contributing.''
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    Regardless, the District took part in the emission control strategy 
consultation process as a member of MANE-VU. As part of that process, 
MANE-VU developed a set of emissions reduction measures identified as 
being necessary to make reasonable progress in the five MANE-VU Class I 
areas. This strategy consists of six Asks for states within MANE-VU and 
five Asks for states outside the region that were found to impact 
visibility at Class I areas within MANE-VU.\36\ The District's 
submission discusses each of the Asks and explains why or why not each 
is applicable and how it has complied with the relevant components of 
the emissions control strategy MANE-VU has laid out for its states. As 
discussed in further detail below, EPA is proposing to find that the 
District has submitted a regional haze plan that meets the requirements 
of 40 CFR 51.308(f)(2) related to the development of a long-term 
strategy for the second implementation period.
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    \36\ See appendix 8 of the DC DOEE 2019 Regional Haze SIP 
submission, ``Statement of the Mid-Atlantic/Northeast Visibility 
Union (MANE-VU) Concerning a Course of Action within MANE-VU toward 
Assuring Reasonable Progress for the Second Regional Haze 
Implementation Period (2018-2028), (August 2017).''
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D. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the URP

    Section 51.308(f)(1) requires states to determine the following for 
each mandatory Class I Federal area located within the State: Baseline 
visibility conditions for the most impaired and clearest days, natural 
visibility conditions for the most impaired and clearest days, progress 
to date for the most impaired and clearest days, the differences 
between current visibility condition and natural visibility condition, 
and the uniform rate of progress. This section also provides the option 
for states to propose adjustments to the URP line to account for the 
impacts from anthropogenic sources outside the United States and the 
impacts from wildland prescribed fires that were conducted for certain, 
specified objectives. 40 CFR 51.308(f)(1)(vi)(B). Because the District 
does not have any Class I areas within its borders, it is not required 
to calculate baseline, current, and natural visibility conditions, or 
to calculate a URP line.\37\
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    \37\ While the District noted that it was not required to comply 
with 40 CFR 51.308(f)(1), elsewhere in its SIP submission (section 
2.22) it included visibility metric graphs of nearby Class I areas, 
which were taken from appendix 13, ``Mid-Atlantic/Northeast U.S. 
Visibility Data 2004-2017 (2nd RH SIP Metrics) (MANE-VU, December 
2018).''
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E. Long-Term Strategy for Regional Haze

    Each state having a Class I area within its borders or emissions 
that may affect visibility in a Class I area must develop a long-term 
strategy for making reasonable progress towards the national visibility 
goal. CAA 169A(b)(2)(B). As explained in Section II.A. of this 
document, the long-term strategy must include the enforceable emission 
limitations, compliance schedules, and other measures that are 
necessary to make reasonable progress, as determined pursuant to 40 CFR 
51.308(f)(2)(i) through (iv). 40 CFR 51.308(f)(2). In determining the 
emission reduction measures necessary to make reasonable progress, the 
state must consider the costs of compliance, time necessary for 
compliance, energy and non-air quality environmental impacts of 
compliance, and the remaining useful life of any existing source. 40 
CFR 51.308(f)(2)(i). As part of this analysis, the state must describe 
the criteria used to determine which sources or group of sources were 
evaluated (i.e., subjected to four-factor analysis) for the second 
implementation period and how the four factors were taken into 
consideration in selecting the measures for inclusion in the long-term 
strategy. 40 CFR 51.308(f)(2)(iii). The long-term strategy for making 
reasonable progress also encompasses any other emission reduction 
measures a state chooses to include in its overall strategy to address 
visibility impairment, e.g., newly adopted or on-the-books/on-the-way 
measures identified pursuant to the five additional factors in 40 CFR 
51.308(f)(2)(iv).
1. The District's Response to the Six MANE-VU Asks
    This section of the document summarizes how the District's SIP 
submission addressed the requirements of 40 CFR 51.308(f)(2)(i); 
specifically, it describes MANE-VU's development of the six Asks and 
how the District addressed each. EPA's evaluation of the District's SIP 
revision with regard to the same is contained in the following section, 
Section IV.E.2. of this document.
    States may rely on technical information developed by the RPOs of 
which they are members to select sources for four-factor analysis and 
to conduct that analysis, as well as to satisfy the documentation 
requirements under 40 CFR 51.308(f). Where an RPO has performed source 
selection and/or four-factor analyses (or considered the five 
additional factors in 40 CFR 51.308(f)(2)(iv)) for its member states, 
those states may rely on the RPOS's analyses for the purpose of 
satisfying the requirements of 40 CFR 51.308(f)(2)(i) so long as the 
states have a reasonable basis to do so and all state participants in 
the RPO process have approved the technical analyses. States may also 
satisfy the requirement of 40 CFR 51.308(f)(2)(ii) to engage in 
interstate consultation with other states that have emissions that are 
reasonably anticipated to contribute to visibility impairment in a 
given Class I area under the auspices of intra- and inter-RPO 
engagement.
    The District is a member of the MANE-VU RPO and participated in the 
RPO's regional approach to developing a strategy for making reasonable 
progress towards the national visibility goal in the MANE-VU Class I 
areas. MANE-VU's strategy includes a combination of (1) measures for 
certain source sectors and groups of sectors that the RPO determined 
were reasonable for

[[Page 19804]]

states to pursue, and (2) a request for member states to conduct four-
factor analyses for individual sources that it identified as 
contributing to visibility impairment. MANE-VU refers to each of the 
components of its overall strategy as an Ask of its member states. On 
August 25, 2017, the Executive Director of MANE-VU, on behalf of the 
MANE-VU states and tribal nations, signed a statement that identifies 
six emission reduction measures that comprise the Asks for the second 
implementation period.\38\ The Asks were ``designed to identify 
reasonable emission reduction strategies that must be addressed by the 
states and tribal nations of MANE-VU through their regional haze SIP 
updates.'' \39\ The Statement explains that ``[i]f any State cannot 
agree with or complete a Class I State's Asks, the State must describe 
the actions taken to resolve the disagreement in the Regional Haze 
SIP.'' \40\
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    \38\ See appendix 8 of the DC DOEE 2019 Regional Haze SIP 
submission, ``Statement of the Mid-Atlantic/Northeast Visibility 
Union (MANE-VU) States Concerning a Course of Action Within MANE-VU 
Toward Assuring Reasonable Progress for the Second Regional Haze 
Implementation Period (2018-2028)'' at 1 August 25, 2017.
    \39\ Id.
    \40\ Id.
---------------------------------------------------------------------------

    MANE-VU's recommendations as to the appropriate control measures 
were based on technical analyses documented in the RPO's reports and 
included as appendices to or referenced in the District's regional haze 
SIP submission. One of the initial steps of MANE-VU's technical 
analysis was to determine which visibility-impairing pollutants should 
be the focus of its efforts for the second implementation period. In 
the first implementation period, MANE-VU determined that sulfates were 
the most significant visibility impairing pollutant at the region's 
Class I areas. To determine the impact of certain pollutants on 
visibility at Class I areas for the purpose of second implementation 
period planning, MANE-VU conducted an analysis comparing the pollutant 
contribution on the clearest and most impaired days in the baseline 
period (2000-2004) to the most recent period (2012-2016) \41\ at MANE-
VU and nearby Class I areas. MANE-VU found that while SO2 
emissions were decreasing and visibility was improving, sulfates still 
made up the most significant contribution to visibility impairment at 
MANE-VU and nearby Class I areas. According to the analysis, 
NOX emissions have begun to play a more significant role in 
visibility impacts in recent years, especially at Brigantine Wilderness 
Area. The District included this analysis in its submission.\42\
---------------------------------------------------------------------------

    \41\ The period of 2012-2016 was the most recent period for 
which data was available at the time of analysis.
    \42\ See appendix 14 of the DC DOEE 2019 Regional Haze SIP 
submission, ``Mid-Atlantic/Northeast U.S. Visibility Data 2004-2016 
(2nd RH SIP Metrics).''
---------------------------------------------------------------------------

    To support development of the Asks, MANE-VU gathered information on 
each of the four factors for six source sectors it determined ``had 
emissions that were reasonabl[y] anticipated to contribute to 
visibility degradation in MANE-VU:'' Electric generating units (EGUs), 
industrial/commercial/institutional boilers (ICI boilers), cement 
kilns, heating oil, residential wood combustion, and outdoor wood 
combustion.\43\ MANE-VU also collected data on individual sources 
within the EGU, ICI boiler, and cement kiln sectors.\44\ Information 
for the six sectors included explanations of technically feasible 
control options for SO2 or NOX, illustrative 
cost-effectiveness estimates for a range of model units and control 
options, sector-wide cost considerations, potential time frames for 
compliance with control options, potential energy and non-air-quality 
environmental impacts of certain control options, and how the remaining 
useful lives of sources might be considered in a control analysis.\45\ 
Source-specific data included SO2 emissions \46\ and 
existing controls \47\ for certain existing EGUs, ICI boilers, and 
cement kilns. MANE-VU had this information on the four factors as well 
as the analyses developed by the RPO's Technical Support Committee 
before it when it determined the specific emission reduction measures 
that are reasonable for certain sources within two of the sectors it 
had examined--EGUs and ICI boilers.
---------------------------------------------------------------------------

    \43\ MANE-VU Four Factor Data Collection Memo at 1, March 30, 
2017, available at https://otcair.org/MANEVU/Upload/Publication/Reports/Four-Factor%20Data%20Collection%20Memo%20-%20170314.pdf. The 
six sectors were identified in the first implementation period 
pursuant to MANE-VU's contribution assessment; MANE-VU subsequently 
updated its information on these sectors for the second 
implementation period.
    \44\ 2016 Updates to the Assessment of Reasonable Progress for 
Regional Haze in MANE-VU Class I Areas, January 31, 2016, available 
at https://s3.amazonaws.com/marama.org/wp-content/uploads/2019/09/13095234/FINAL_Updates_to_4Factor_Reasonable_Progress_Report_2016_01_31.pdf.
    \45\ Id.
    \46\ Table 1 of MANE-VU's ``Four Factor Data Collection Memo'' 
March 30, 2017 contains 2011 SO2 data from specific 
sources.
    \47\ The ``Status of the Top 167 Electric Generating Units 
(EGUs) that Contributed to Visibility Impairment at MANE-VU Class I 
Areas during the 2008 Regional Haze Planning Period'' July 25, 2016 
reviews the existing and soon to be installed, at the time of the 
report, emission controls at individual EGU sources that were a part 
of the MANE-VU Ask from the first implementation period. Available 
at: https://otcair.org/MANEVU/Upload/Publication/Reports/Status%20of%20the%20Top%20167%20Stacks%20from%20the%202008%20MANE-VU%20Ask.pdf.
---------------------------------------------------------------------------

    MANE-VU Ask 1 is ``ensuring the most effective use of control 
technologies on a year-round basis'' at EGUs with a nameplate capacity 
larger than or equal to 25 megawatts (MW) with already installed 
NOX and/or SO2 controls.\48\ In its submission, 
the District explained that it has no coal-fired EGUs with a nameplate 
capacity greater than 25 MW and that it is currently meeting Ask 1.
---------------------------------------------------------------------------

    \48\ See appendix 8 of the DC DOEE 2019 Regional Haze SIP 
submission, ``Statement of the Mid-Atlantic/Northeast Visibility 
Union (MANE-VU) Concerning a Course of Action within MANE-VU toward 
Assuring Reasonable Progress for the Second Regional Haze 
Implementation Period (2018-2028), (August 2017).''
---------------------------------------------------------------------------

    MANE-VU Ask 2 consists of a request that states ``perform a four-
factor analysis for reasonable installation or upgrade to emissions 
controls'' for specified sources. MANE-VU developed its Ask 2 list of 
sources for analysis by performing modeling and identifying facilities 
with the potential for 3.0 inverse megameters (Mm-\1\) or 
greater impacts on visibility at any Class I area in the MANE-VU 
region. The District explained that it has no facilities that were 
modeled by MANE-VU to impact visibility at any Class I area by 3.0 
Mm-\1\ or more and concluded that it is currently meeting 
Ask 2.
    Ask 3 is for each MANE-VU state to pursue an ultra low-sulfur fuel 
oil standard if it has not already done so in the first implementation 
period. The Ask includes percent by weight standards for #2 distillate 
oil (0.0015% sulfur by weight or 15 part per million (ppm)), #4 
residual oil (0.25-0.5% sulfur by weight), and #6 residual oil (0.3-
0.5% sulfur by weight). The District explains that, in 2016, EPA 
approved into the DC SIP the District's regulation to reduce the sulfur 
content of commercial fuel oil (20 DCMR Section 801). 81 FR 70020 (Oct. 
11, 2016). The final rule called for a 2,500 ppm limit (0.25% sulfur by 
weight) on #4 oil in 2016 and a 15 ppm limit (0.0015% sulfur by weight) 
on #2 oil starting in 2018. The rule also banned the sale of #5 and #6 
fuel oil after July 1, 2016. The emissions reductions expected from 
implementing the 15 ppm provisions will be achieved during the second 
implementation period and the ultra low-sulfur fuel oil regulations in 
the District are a part of its long-term strategy. The District 
therefore concluded that it is meeting Ask 3.
    MANE-VU Ask 4 requests states to update permits to ``lock in'' 
lower emissions rates for NOX, SO2, and PM

[[Page 19805]]

at emissions sources larger than 250 million British Thermal Units 
(MMBtu) per hour heat input that have switched to lower emitting fuels. 
According to the District's SIP submission, the only facility in the 
District that is larger than 250 MMBtu is the U.S. General Services 
Administration Central Heating and Refrigeration Plant (``GSA Central 
Heating Plant''). While the facility originally burned coal, in July 
2000 it was limited through a federally enforceable Title V permit 
revision to the use of natural gas, with #2 fuel oil (maximum 0.05% 
sulfur by weight) to be used only as a back-up fuel when the natural 
gas supply is interrupted by the supplier. The District stated that no 
additional updates are needed at the facility for this Ask.
    Ask 5 requests that states ``control NOX emissions for 
peaking combustion turbines'' (capable of generating 15 MW or more of 
electricity) ``that have the potential to operate on high electric 
demand days'' by either (1) meeting NOX emissions standards 
specified in the Ask for turbines that run on natural gas and for fuel 
oil, (2) performing a four-factor analysis for reasonable installation 
of or upgrade to emission controls, or (3) obtaining equivalent 
emission reductions on high electric demand days.\49\ The District 
states in its submission that it has no combustion turbines that sell 
electricity to the grid during high electricity demand days, but also 
notes that its reasonably available control technology (RACT) rule for 
combustion turbines, associated heat recovery steam generators, and 
duct burners that was approved into the SIP on February 24, 2020 (85 FR 
10295), applies to all combustion turbines in the District regardless 
of their electricity generation capabilities. The District further 
explains that its RACT rule, which the District adopted to comply with 
the NOX RACT requirements under the 2008 Ozone National 
Ambient Air Quality Standards (NAAQS), meets the NOX 
emission rates that MANE-VU provided states should strive to meet under 
Ask 5.\50\ The District states in its submission that it finds that 
this RACT rule would comply with Ask 5.
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    \49\ See appendix 8 of the DC DOEE 2019 Regional Haze SIP 
submission.
    \50\ See Section V of this proposed rulemaking for a discussion 
of the correction that EPA is proposing for the DC NOX 
RACT rule.
---------------------------------------------------------------------------

    The last Ask for states within MANE-VU (Ask 6) requests states to 
report in their regional haze SIPs about programs that decrease energy 
demand and increase the use of combined heat and power (CHP) and other 
distributed generation technologies such as fuel cells, wind and solar. 
The District explains in its SIP submission that it ``has a variety of 
programs and initiatives underway that reduce air pollution through 
reduced energy use, energy efficiency, cogeneration, or clean 
distributed generation.'' \51\ The SIP submission specifically cites 
three cogeneration facilities the District has permitted since 2011 as 
well as its 2006 Green Building Act.
---------------------------------------------------------------------------

    \51\ See section 2.5.6 of the DC DOEE 2019 Regional Haze SIP 
submission at 16.
---------------------------------------------------------------------------

2. EPA's Evaluation of the District's Response to the Six MANE-VU Asks 
and Compliance With 40 CFR 51.308(f)(2)(i)
    EPA is proposing to find that the District has satisfied the 
requirements of 40 CFR 51.308(f)(2)(i) related to development of a 
long-term strategy. As explained above, MANE-VU conducted an inventory 
analysis to identify the source sectors that produced the greatest 
amount of SO2 and NOX emissions in 2011; 
inventory data were also projected to 2018. Based on this analysis, 
MANE-VU identified the top-emitting sectors for each of the two 
pollutants, which for SO2 include coal-fired EGUs, 
industrial boilers, oil-fired EGUs, and oil-fired area sources 
including residential, commercial, and industrial sources. Major-
emitting sources of NOX include on-road vehicles, non-road 
vehicles, and EGUs.\52\ The RPO's documentation explains that ``[EGUs] 
emitting SO2 and NOX and industrial point sources 
emitting SO2 were found to be sectors with high emissions 
that warranted further scrutiny. Mobile sources were not considered in 
this analysis because any ask concerning mobile sources would be made 
to EPA and not during the intra-RPO and inter-RPO consultation process 
among the states and tribes.'' \53\ Thus, in selecting sources and 
source sectors for further analysis, we are proposing to find that the 
District's reliance on the technical analysis provided by MANE-VU, and 
adopted by all ``State participants,'' per 40 CFR 51.308(f)(2)(iii), 
demonstrates that the District reasonably evaluated sources of the two 
pollutants--SO2 and NOX--that drive visibility 
impairment within the MANE-VU region and that it adequately explained 
and supported its choice of sources and source categories for further 
analysis.
---------------------------------------------------------------------------

    \52\ See ``Contribution Assessment Preliminary Inventory 
Analysis (October 10, 2016)'' available at: https://otcair.org/MANEVU/Upload/Publication/Reports/Contribution%20Assessment%20Preliminary%20Inventory%20Analysis.pdf.
    \53\ See appendix 7 of the DC DOEE 2019 Regional Haze SIP 
submission, ``MANE-VU Regional Haze Consultation Report'' at 3, July 
27, 2018.
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    Section 51.308(f)(2)(i) requires states to evaluate and determine 
the emission reduction measures that are necessary to make reasonable 
progress by applying the four factors to sources. As explained 
previously, the MANE-VU Asks are a mix of measures for sectors and 
groups of sources identified as reasonable for states to address in 
their regional haze plans and requests for states to perform four-
factor analyses for specific sources the RPO identified as potentially 
contributing to visibility impairment. As laid out in further detail 
below, EPA is proposing to find that MANE-VU's four-factor analysis 
conducted to support Ask 3, in conjunction with the District's analysis 
and explanation of how it has either complied with each Ask or 
determined that it is not applicable, satisfies the requirement to 
determine the emission reduction measures that are necessary to make 
reasonable progress by considering the costs of compliance, time 
necessary for compliance, energy and non-air quality impacts of 
compliance, and remaining useful life of any potentially affected 
sources.
    The District concluded that it satisfied Ask 1 because it has no 
coal-fired EGUs with a nameplate capacity of greater than 25 MW. EPA 
notes that Ask 1 does not refer exclusively to coal-fired EGUs; 
however, a review of the NEI and Clean Air Markets Division data shows 
that the District does not have any EGUs with a capacity greater than 
25 MW.\54\ EPA therefore proposes to find that the District's 
conclusion that it is currently meeting Ask 1 is reasonable.
---------------------------------------------------------------------------

    \54\ EPA notes that the GSA Central Heating Plant and Capital 
Power Plant are not considered EGUs and therefore finds it 
reasonable that the District did not include them in its 
consideration of Ask 1.
---------------------------------------------------------------------------

    Ask 2 addresses the sources MANE-VU determined have the potential 
for >=3 Mm-\1\ visibility impact at any MANE-VU Class I 
area; the Ask requests MANE-VU states to conduct four-factor analyses 
for the specified sources within their borders. This Ask explicitly 
engages with the statutory and regulatory requirement to determine 
reasonable progress based on the four factors; MANE-VU considered it 
``reasonable to have the greatest contributors to visibility impairment 
conduct a four-factor analysis that would determine whether emission 
control measures should be pursued and what would be reasonable for 
each source.'' \55\
---------------------------------------------------------------------------

    \55\ Id at 4.
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    The District did not conduct a four-factor analysis for any 
individual point

[[Page 19806]]

sources of visibility-impairing pollutants. It is relevant to our 
evaluation of the reasonableness of this decision that not only did 
MANE-VU not identify any large EGUs or other industrial sources of 
visibility impairing pollutants within the District, the District does 
not actually contain any point sources with large emissions of 
visibility impairing pollutants. The 2014 NEI data included in the 
District's submission show that total actual point source emissions for 
SO2 District-wide were less than 50 tons and less than 500 
tons for NOX. Data EPA pulled from the 2017 NEI show that 
total actual point source emissions for SO2 District-wide 
were less than 30 tons and less than 400 tons for NOX.\56\ 
That the District's emissions are this low on a jurisdiction-wide basis 
reinforces the reasonableness of the its decision to not apply the four 
factors to any individual point source of visibility impairing 
pollutants in the second implementation period.
---------------------------------------------------------------------------

    \56\ See ``2017 National Emissions Inventory Data for the 
District of Columbia for Select Pollutants'' in the docket.
---------------------------------------------------------------------------

    The District does contain one source that is >250 MMBtu/hour, the 
GSA Central Heating Plant; a steam plant and refrigeration facility 
(produces both steam for heat and process energy and chilled water for 
refrigeration) that also uses co-generation to produce both heat energy 
and electricity for use on site. The GSA Central Heating Plant is the 
largest point source of emissions (by combined NOX and 
SO2 emissions) in the District as reported under the NEI. It 
was also the subject of the NPS's 2018 early engagement source 
evaluation request in which that agency provided a list of sources and 
requested that states review and consider those sources for inclusion 
in their long-term strategies.\57\ For the following reasons, EPA 
believes the District reasonably declined to conduct a four-factor 
analysis for the GSA Central Heating Plant.\58\ First, as reported 
under the 2017 NEI, the GSA Central Heating Plant's total emissions are 
relatively low at 127 tons per year NOX and 0.6 tons per 
year SO2.\59\ Second, emissions from the source are already 
subject to both operational limits and enforceable emission limits 
including the District's NOX RACT rule, which has been 
adopted into its SIP.\60\ The Plant's NOX emissions come 
from five boilers and one cogeneration system that is comprised of two 
combustion turbine generators, one heat recovery steam generator, and 
duct burners.\61\ Each of the five boilers is equipped with low 
NOX burners or dry low NOX burners \62\ and is 
limited by the source's Title V permit (permit No. 032) to burning 
natural gas except for periods of service interruption, when the 
boilers are permitted to burn #2 fuel oil.\63\ The 15 ppm low sulfur 
fuel oil rule applies to any fuel oil that would be used at the GSA 
Central Heating Plant. The boilers, three of which are rated at 250 
MMBtu/hour and two of which are rated at 500 MMBtu/hour, are 
additionally limited under the NOX RACT rule to 0.25 lb 
NOX/MMBtu when powered by fuel oil or a combination of oil 
and natural gas, and 0.2 lb NOX/MMBtu when powered by 
natural gas. The two larger boilers, as well as the cogeneration unit, 
are further subject to a cap of 25 tons of NOX total per 
ozone season; this cap was required pursuant to EPA's NOX 
SIP call and has been approved into the District's SIP.\64\ The 
combustion turbines that are part of the GSA Central Heating Plant's 
cogeneration system are also limited to burning natural gas except for 
periods of service interruption, when they are permitted to burn #2 
fuel oil. The turbines are inherently low emitting by virtue of their 
dry low NOX burners and emissions are also limited by the 
NOX RACT rule, which contains requirements for combustion 
turbines and associated heat recovery steam generators and duct burners 
equivalent to the New Source Performance Standards (NSPS) in subpart 
KKKK. The duct burners at the GSA Central Heating Plant are fired 
exclusively on natural gas.\65\ Based on the fact that the GSA Central 
Heating Plant's emissions are already relatively low and controlled as 
the result of SIP-based limits on SO2 (low sulfur fuel oil 
rule) and NOX (NOX RACT rule and limits related 
to NOX SIP call), EPA believes it was reasonable for the 
District not to conduct a four-factor analysis for this source, whether 
or not it was on the MANE-VU list of sources pursuant to Ask 2.
---------------------------------------------------------------------------

    \57\ See appendix 9 of the DC DOEE 2019 Regional Haze SIP 
submission, ``National Park Service Letter to MANE-VU (April 
2018).''
    \58\ The District's response to the NPS's early engagement 
request is contained in section 2.5.7. of the DC DOEE 2019 Regional 
Haze SIP submission at 17.
    \59\ See ``2017 National Emissions Inventory Data for the 
District of Columbia for Select Pollutants'' in the docket.
    \60\ 85 FR 10295 (February 24, 2020). The District's 
NOX RACT rule went into effect on July 23, 2018.
    \61\ The District of Columbia's DOEE SIP Submission on 
Reasonably Available Control Technology (RACT) for Oxides of 
Nitrogen (NOX) Determination for the 2008 8-Hour Ozone 
National Ambient Air Quality Standards (NAAQS) (``DC DOEE 2018 
NOX RACT submission'') at 5-6, August 29, 2018. (February 
24, 2020, 85 FR 10295).
    \62\ DC DOEE 2018 NOX RACT submission at 5-6.
    \63\ Section 2.5.7 of the DC DOEE 2019 Regional Haze SIP 
submission at 18.
    \64\ 81 FR 8656 (February 22, 2016); DC DOEE 2018 NOX 
RACT Submission at 9.
    \65\ DC DOEE 2019 Regional Haze SIP submission at 17-18; DC DOEE 
2018 NOX RACT submission at 15.
---------------------------------------------------------------------------

    Ask 3, which addresses the sulfur content of heating oil used in 
MANE-VU states, is based on a four-factor analysis for the heating oil 
sulfur reduction regulations contained in that Ask; \66\ specifically, 
for reducing the sulfur content of distillate oil to 15 ppm. The 
analysis started with an assessment of the costs of retrofitting 
refineries to produce 15 ppm heating oil in sufficient quantities to 
support implementation of the standard, as well as the impacts of 
requiring a reduction in sulfur content on consumer prices. The 
analysis noted that, as a result of previous EPA rulemakings to reduce 
the sulfur content of on-road and non-road-fuels to 15 ppm, 
technologies are currently available to achieve sulfur reductions and 
many refiners are already meeting this standard, meaning that the 
capital investments for further reductions in the sulfur content of 
heating oil are expected to be relatively low compared to costs 
incurred in the past. The analysis also examined, by way of example, 
the impacts of New York's existing 15 ppm sulfur requirements on 
heating oil prices and concluded that the cost associated with reducing 
sulfur was relatively small in terms of the absolute price of heating 
oil compared to the magnitude of volatility in crude oil prices. It 
also noted that the slight price premium is compensated by cost savings 
due to the benefits of lower-sulfur fuels in terms of equipment life 
and maintenance and fuel stability. Consideration of the time necessary 
for compliance with a 15 ppm sulfur standard was accomplished through a 
discussion of the amount of time refiners had needed to comply with 
EPA's on-road and non-road fuel 15 ppm requirement, and the 
implications existing refinery capacity and distribution infrastructure 
may have for compliance times with a 15 ppm heating oil standard. The 
analysis concluded that with phased-in timing for states that have not 
yet adopted a 15 ppm heating oil standard there ``appears to be 
sufficient time to allow refiners to add any additional heating oil 
capacity that may be required.'' \67\ The analysis further noted the 
beneficial energy and non-air quality environmental impacts

[[Page 19807]]

of a 15 ppm sulfur heating oil requirement and that reducing sulfur 
content may also have a salutary impact on the remaining useful life of 
residential furnaces and boilers.\68\
---------------------------------------------------------------------------

    \66\ See ``2016 Updates to the Assessment of Reasonable Progress 
for Regional Haze in MANE-VU Class I Areas'' at 8-4, January 31, 
2016, available at: https://s3.amazonaws.com/marama.org/wp-content/uploads/2019/09/13095234/FINAL_Updates_to_4Factor_Reasonable_Progress_Report_2016_01_31.pdf.
    \67\ Id. at 8-7.
    \68\ Id. at 8-8.
---------------------------------------------------------------------------

    EPA proposes to find that the District reasonably relied on MANE-
VU's four-factor analysis for a low-sulfur fuel oil regulation, which 
engaged with each of the factors and explained how the information 
supported a conclusion that a 15 ppm-sulfur fuel oil standard is 
reasonable. The agency further proposes to determine that the 
District's SIP-approved ultra-low sulfur fuel oil rule satisfies the 
requirement of 40 CFR 51.308(f)(2) that its long-term strategy include 
the enforceable measures that are necessary to make reasonable 
progress, as determined through consideration of the four factors.\69\
---------------------------------------------------------------------------

    \69\ The District notes in its SIP submission, its regulations 
were incorporated into its SIP on October 11, 2016 (81 FR 70020).
---------------------------------------------------------------------------

    The District concluded that no additional updates were needed to 
meet Ask 4, which requests MANE-VU states to pursue updating permits, 
enforceable agreements, and/or rules to lock-in lower emission rates 
for sources >250 MMBtu per hour that have switched to lower emitting 
fuels. As explained above, the GSA Central Heating Plant is the only 
point source >250 MMBtu per hour in the District. While the boilers 
were originally configured to burn coal, in 2000 the source updated its 
Title V permit to limit the source to using only natural gas as a 
primary fuel and #2 fuel oil during natural gas supply 
interruptions.\70\ Thus, EPA proposes to find that the District 
reasonably determined it has satisfied Ask 4.
---------------------------------------------------------------------------

    \70\ See section 2.5.4 of the DC DOEE 2019 Regional Haze SIP 
submission.
---------------------------------------------------------------------------

    Ask 5 addresses NOX emissions from peaking combustion 
turbines that have the potential to operate on high electric demand 
days. The District notes that, while it has no combustion turbines that 
sell electricity to the grid during such days, its SIP-adopted 
NOX RACT rule applies to all combustion turbines and meets 
the emission rates contained in Ask 5. EPA therefore proposes to find 
that the District reasonably concluded that its existing regulations 
would comply with Ask 5.
    Finally, with regard to Ask 6, the District reports three 
cogeneration facilities it has permitted and describes the provisions 
of its 2006 Green Building Act. EPA is proposing to find that the 
District has satisfied Ask 6's request to consider and report in its 
SIP measures or programs related to energy efficiency, cogeneration, 
and other clean distributed generation technologies.
    In sum, EPA is proposing to find that, based on the District's 
participation in the MANE-VU planning process, how it has addressed 
each of the Asks, and EPA's assessment of the District's emissions and 
point sources, the District has complied with the requirements of 40 
CFR 51.308(f)(2)(i). The Agency notes that MANE-VU concluded that 
sulfates from SO2 emissions were still the primary driver of 
visibility impairment in the second implementation period \71\ and that 
MANE-VU conducted a four-factor analysis to support Ask 3, which 
requests that states pursue ultra-low sulfur fuel oil standards to 
address SO2 emissions. The District has done so and included 
its regulations in its SIP, thus satisfying the requirements that 
states determine the emission reduction measures necessary to make 
reasonable progress by considering the four factors and that their 
long-term strategies include the enforceable emission limitations, 
compliance schedules, and other measures necessary to make reasonable 
progress. EPA further believes it is reasonable that the District did 
not examine additional sources for potential emission reduction 
measures in the second implementation period because there are no large 
point sources of visibility-impairing pollutants in the jurisdiction; 
furthermore, the largest category of area sources of SO2 
emissions are oil-fired residential, commercial, and industrial sources 
that are covered by the fuel oil standard and the largest area source 
category of NOX emissions is mobile sources. In particular, 
EPA believes it was reasonable for the District not to conduct a four-
factor analysis for the GSA Central Heating Plant--the largest point 
source of emissions--because that facility's emissions are already 
relatively low and, critically, are already limited by SIP-based 
emission limits, in addition to permit-based fuel requirements. 
Additionally, to the extent that MANE-VU has identified the measures in 
Asks 4 through 6 as being part of the region's strategy for making 
reasonable progress, we propose to find it reasonable for the District 
to address these Asks by pointing to existing and on-the-way measures 
that satisfy each.
---------------------------------------------------------------------------

    \71\ See section 2.4.2 of the DC DOEE 2019 Regional Haze SIP 
submission.
---------------------------------------------------------------------------

3. Additional Long-Term Strategy Requirements
    EPA also proposes to determine that the District has satisfied the 
consultation requirements of 40 CFR 51.308(f)(2)(ii). The District 
participated in and provided documentation of the MANE-VU intra- and 
inter-RPO consultation processes and addressed each of the MANE-VU 
Asks, either by explaining why an Ask is not applicable or providing 
information on the measures it has in place that satisfy an Ask.\72\ 
EPA proposes to find that the District's explanations with regard to 
Asks 1 and 2, for which the District did not offer any measures 
pursuant to MANE-VU's requests, are reasonable given the District's 
lack of sources that fit the applicability criteria for those Asks 
(EGUs with capacity >=25 MW and sources with the potential for >=3.0 
m-\1\ visibility impact).
---------------------------------------------------------------------------

    \72\ The District provided documentation of the MANE-VU 
consultation process in appendix 5, ``Inter-RPO State/Tribal and FLM 
Consultation Framework (5/10/2006)'', appendix 6, ``MANE VU Regional 
Haze Consultation Plan (5/5/2017)'', and appendix 7, ``MANE-VU 
Regional Haze Consultation Report (7/27/2018)'' of its 2019 Regional 
Haze SIP submission.
---------------------------------------------------------------------------

    The District chose to rely on MANE-VU's technical information, 
modeling, and analysis to support development of its long-term 
strategy. EPA proposes to find that the documentation developed by 
MANE-VU and provided and referenced by the District in its submission 
satisfies the requirements of 40 CFR 51.308(f)(2)(iii). As required in 
40 CFR 51.308(f)(2)(iii), the emissions information considered to 
determine what is necessary to make reasonable progress included 
information on emissions for the most recent year for which the state 
has submitted triennial emissions data to EPA (or a more recent year), 
with a 12-month exemption period for newly submitted data. The 
District's submission includes emissions inventory data from 2014, 
which was the most recent year of data that the District had submitted 
to EPA to meet the triennial reporting requirement within 12 months 
prior to the District's submittal in November 2019.\73\ EPA proposes to 
find that the District has satisfied the emission inventory requirement 
in 40 CFR 51.308(f)(2)(iii).
---------------------------------------------------------------------------

    \73\ See section 2.20 of the DC DOEE 2019 Regional Haze SIP 
submission.
---------------------------------------------------------------------------

    EPA also proposes to find that the District considered the five 
additional factors in 40 CFR 51.308(f)(2)(iv) in developing its long-
term strategy. Pursuant to 40 CFR 51.308(f)(2)(iv)(A), the District 
noted that ongoing federal emission control programs, including boiler 
and Reciprocating Internal Combustion Engine (RICE) National Emission 
Standards for Hazardous Air Pollutants (NESHAP) requirements, portable 
fuel container rules, and New Source Performance Standards (NSPS) for 
stationary compression ignition engines, would impact emissions from 
point and nonpoint sources in the

[[Page 19808]]

second implementation period. For the on-road and non-road source 
categories, the District identified equipment turnover, fuel 
requirements, and the transportation conformity regulation (May 28, 
2010, 75 FR 29894) as continuing factors that contribute to emission 
reductions through 2028. On-going measures from various source 
categories that the District considered in developing its long-term 
strategy were the NOx emissions budget approved by EPA on February 22, 
2016 (81 FR 8656), NOx RACT requirements for Combustion Turbines 
(February 24, 2020, 85 FR 10295), and the sulfur content of fuel oil 
rule (October 11, 2016, 81 FR 70020).
    The District's consideration of measures to mitigate the impacts of 
construction activities as required by 40 CFR 51.308(f)(2)(iv)(B) 
includes discussion of a report that found that, from a regional haze 
perspective, crustal material from anthropogenic sources does not play 
a major role in visibility impairment at MANE-VU Class I areas.\74\ 
While construction activities can be responsible for direct PM 
emissions in the region, the dust settles out of the air relatively 
close to the sources and does not impact visibility at distant Class I 
areas significantly. The District cited its `Control of Fugitive Dust' 
regulation which requires reasonable precautions to minimize emissions 
of fugitive dust (August 28, 1995, 60 FR 44431) as one measure used to 
control PM emissions in the District. A summary of the PM emission 
inventory in the District can be found in Section IV.H. of this 
rulemaking.\75\
---------------------------------------------------------------------------

    \74\ See appendix 12 of the DC DOEE 2019 Regional Haze SIP 
submission, ``The Nature of the Fine Particle and Regional Haze Air 
Quality Problems in the MANE-VU Region: A Conceptual Description 
(NESCAUM, November 2006, Revised August 2010)'' at 3-8 of section 
3.1.4.
    \75\ Section 2.20.2 of the DC DOEE 2019 Regional Haze SIP 
submission addresses the PM10 inventory for DC.
---------------------------------------------------------------------------

    Source retirements and replacement schedules are addressed pursuant 
to 40 CFR 51.308(f)(2)(iv)(C) in section 2.7.3 of the District's 
submission. The shutdown of only one large EGU or industrial source in 
the District--the Pepco Benning Road Generation Station, which retired 
in 2012--is reflected in the emissions inventories used for the MANE-VU 
contribution assessment. In addressing smoke management as required in 
40 CFR 51.308(f)(2)(iv)(D), the District explained that it is an urban 
area and does not have agricultural or prescribed forest burns and thus 
does not have a smoke management plan.\76\ The District also asserts 
that additional measures to mitigate smoke emissions from agricultural 
and forest fires are not needed in its SIP, although the submission 
does cite a regulation that limits seasonal open burning (August 28, 
1995, 60 FR 44431).
---------------------------------------------------------------------------

    \76\ See section 2.7.4 of the DC DOEE 2019 Regional Haze SIP 
submission at 24.
---------------------------------------------------------------------------

    The District discussed its consideration of the anticipated net 
effect of projected changes in emissions as required by 40 CFR 
51.308(f)(2)(iv)(E) by explaining how MANE-VU's visibility modeling for 
2028 incorporates such projected changes. MANE-VU conducted 
photochemical modeling for the 2018-2028 implementation period after 
consultation with states within and outside of the RPO. The 2028 base 
case considers only on-the-books controls, and a 2028 control case 
considers implementation of the MANE-VU Asks. For the District, the 
2028 base-case modeling included the District's measures pursuant to 
Asks 4 and 5, while the low sulfur fuel oil measure consistent with Ask 
3 was included only in the 2028 control case modeling. The SIP revision 
notes the projected visibility conditions in five Class I areas--
Brigantine Wilderness, Otter Creek/Dolly Sods Wildernesses, James River 
Face Wilderness, and Shenandoah National Park--on the most impaired and 
clearest days under the 2028 base case.\77\
---------------------------------------------------------------------------

    \77\ See appendix 11 or section 2.22 of the DC DOEE 2019 
Regional Haze SIP submission.
---------------------------------------------------------------------------

    Because the District has considered each of the five additional 
factors, discussed the measures it has in place to address each (or 
discussed why such measures are not needed), and, where relevant, 
explained how each factor informed MANE-VU's technical analysis for 
second implementation period planning for reasonable progress, EPA 
proposes to find that the District has satisfied the requirements of 40 
CFR 51.308(f)(2)(iv).

F. Reasonable Progress Goals

    Section 51.308(f)(3)(i) requires a state in which a Class I area is 
located to establish reasonable progress goals-one each for the most 
impaired and clearest days-reflecting the visibility conditions that 
will be achieved as a result of implementing the long-term strategy. 
The District is not required to establish RPGs because it does not have 
a Class I area.
    Section 51.308(f)(3)(ii) applies in circumstances in which a Class 
I area's RPG for the most impaired days represents a slower rate of 
visibility improvement than the uniform rate of progress calculated 
under 40 CFR 51.308(f)(1)(vi). Under 40 CFR 51.308(f)(3)(ii)(B), a 
state that contains sources that are reasonably anticipated to 
contribute to visibility impairment in such a Class I area must 
demonstrate that there are no additional emission reduction measures 
that would be reasonable to include in its long-term strategy. The 
District's SIP revision included the modeled MANE-VU 2028 visibility 
projections at nearby Class I areas.\78\ While these projections may 
not represent the final RPGs for these Class I areas, all of the 2028 
projections for the most impaired days at these areas (Brigantine, 
Dolly Sods/Otter Creek, Shenandoah, and James River Face) are well 
below the respective 2028 glidepaths. In addition, we note that the 
District's largest contribution is to Brigantine Wilderness in New 
Jersey. New Jersey submitted its regional haze SIP to EPA on March 26, 
2020 and the proposed RPG for Brigantine was also well below the 2028 
glidepath.\79\ EPA proposes to determine that the District has 
satisfied the applicable requirements of 40 CFR 51.308(f)(3) relating 
to reasonable progress goals.
---------------------------------------------------------------------------

    \78\ Section 2.22 of the DC DOEE 2019 Regional Haze SIP 
submission.
    \79\ New Jersey submitted its second regional haze SIP on March 
26, 2020 and supplemented the documentation on September 8, 2020. At 
the time of this document, EPA has not yet proposed to approve or 
disapprove New Jersey's determination with regard to the RPGs for 
Brigantine Wilderness Area.
---------------------------------------------------------------------------

G. Monitoring Strategy and Other Implementation Plan Requirements

    Section 51.308(f)(6) specifies that each comprehensive revision of 
a state's regional haze SIP must contain or provide for certain 
elements, including monitoring strategies, emissions inventories, and 
any necessary reporting and recordkeeping measures needed to assess and 
report on visibility. A main requirement of this subsection is for 
states with Class I areas to submit monitoring strategies for 
measuring, characterizing, and reporting on visibility impairment. The 
District does not have a Class I area and therefore its SIP is not 
required to provide for a monitoring strategy and associated 
requirements. It is also not subject to the requirements of 40 CFR 
51.308(f)(6)(i), (ii), and (iv), which apply only to states with Class 
I areas and pertain to the establishment of monitoring sites and 
reporting and use of monitoring data. However, the District's SIP is 
required to provide for procedures by which monitoring data and other 
information are used in determining the contribution to emissions to 
visibility impairment in other states. 40 CFR 51.308(f)(6)(iii). 
Pursuant to this requirement, the

[[Page 19809]]

District commits to continuing support of ongoing IMPROVE visibility 
monitoring in Class I areas.\80\
---------------------------------------------------------------------------

    \80\ Section 2.15 of the DC DOEE 2019 Regional Haze SIP 
submission at 28.
---------------------------------------------------------------------------

    The District asserts that it is subject only to the requirements of 
40 CFR 51.308(f)(6)(iii).\81\ EPA disagrees with this statement; the 
District is also subject to 40 CFR 51.308(f)(6)(v) and (vi), which 
apply to all states regardless of whether it has a Class I area. 
Despite the District's misstatement, EPA is proposing to find that its 
SIP provides for the necessary elements to satisfy the applicable 
requirements.
---------------------------------------------------------------------------

    \81\ Id.
---------------------------------------------------------------------------

    Section 51.308(f)(6)(v) requires each state, including states 
without Class I areas, to provide for an inventory of emissions of 
pollutants that are reasonably anticipated to cause or contribute to 
visibility impairment, including emissions for the most recent year for 
which data are available and estimates of future projected emissions. 
It also requires a commitment to update the inventory periodically. The 
District provides for emissions inventories and estimates for future 
projected emissions by participating in the MANE-VU RPO and complying 
with the AERR. In 40 CFR part 51, subpart A, the AERR requires states 
and the District of Columbia to submit emissions inventories for 
criteria pollutants to EPA's Emissions Inventory System (EIS) every 
three years. The emission inventory data is used to develop the NEI, 
which provides for a triennial state-wide inventory of pollutants that 
are reasonably anticipated to cause or contribute to visibility 
impairment. MANE-VU also developed projections of future emissions of 
visibility impairing pollutants and in its submission the District 
commits to continue coordinating with MANE-VU on progress reports, SIP 
revisions, and face-to-face consultation meetings as necessary to 
maintain and improve the visibility in Class I Federal areas.\82\
---------------------------------------------------------------------------

    \82\ See Executive Summary at vii and section 1.5 at 4 of the DC 
DOEE 2019 Regional Haze SIP submission.
---------------------------------------------------------------------------

    Section 2.20 of the District's second implementation period 
regional haze SIP submission includes tables of National Emissions 
Inventory (NEI) data. The source categories of the emissions 
inventories included are: (1) Point sources; (2) nonpoint sources; (3) 
non-road mobile sources; and (4) on-road mobile sources. The point 
source category is further divided into Air Markets Program Data (AMPD) 
point sources and non-AMPD point sources.\83\ The District included NEI 
emissions inventories for the following years: 2002 (one of the 
regional haze program baseline years), 2008, 2011, and 2014; and for 
the following pollutants: SO2, NOX, 
PM10, and NH3. The District's SIP revision was 
submitted in November 2019 and the 2017 NEI was not published until 
2020; therefore, the year of the most recent NEI at the time of 
submission to EPA was 2014. There are additional data from the years of 
2016 and 2017 for SO2 and NOX from the only AMPD 
source listed in the District: The GSA Central Heating Plant. While not 
included in its regional haze submission, the District has a complete 
NEI for 2017.
---------------------------------------------------------------------------

    \83\ AMPD sources are facilities that participate in EPA's 
emission trading programs. The majority of AMPD sources are electric 
generating units (EGUs).
---------------------------------------------------------------------------

    As required in 40 CFR 51.308(f)(6)(v), states must commit to update 
the inventory of emissions of pollutants that are reasonably 
anticipated to cause or contribute to visibility impairment 
periodically. The District chose to rely on the NEI as the inventory of 
these emissions. Under the AERR, states are required to submit 
estimates for all emissions categories to EPA on a three-year cycle. 
EPA finds that the requirements to periodically update the national 
inventory for all emission categories suffices to meet the requirement 
to commit to updating a visibility impairing pollutant inventory for 
the District.
    Section 51.308(f)(6)(v) also requires states to include estimates 
of future projected emissions and include a commitment to update the 
inventory periodically. The District explains in its submission that 
MANE-VU projected emissions to 2028, which is the end of the second 
implementation period.\84\ MANE-VU completed two 2028 projected 
emissions modeling cases--a 2028 base case that considers only on-the-
books controls and a 2028 control case that considers implementation of 
the MANE-VU Asks.\85\ For the District, the only emission reductions 
from new measures included in the control case was implementation of 
the low sulfur fuel oil standard Ask 3. EPA proposes that the District 
has met the requirements of 40 CFR 51.308(f)(6)(v) by its continued 
participation in MANE-VU and on-going compliance with the AERR, and 
that no further elements are necessary at this time for the District to 
assess and report on visibility pursuant to 40 CFR 51.308(f)(6)(vi).
---------------------------------------------------------------------------

    \84\ See section 2.6 of the DC DOEE 2019 Regional Haze SIP 
submission.
    \85\ The District cites these as appendices 9 and 10 in the 
document, but they are ``Technical Support Document for the 2011 
Northeastern U.S. Gamma Emission Inventory (January 2018)'' appendix 
10 and ``Ozone Transport Commission/Mid-Atlantic Northeastern 
Visibility Union 2011 Based Modeling Platform Support Document--
October 2018 Update (October 2018)'' appendix 11 in the SIP 
submission respectively.
---------------------------------------------------------------------------

H. Requirements for Periodic Reports Describing Progress Towards the 
Reasonable Progress Goals

    Section 51.308(f)(5) requires that periodic comprehensive revisions 
of states' regional haze plans also address the progress report 
requirements of 40 CFR 51.308(g)(1) through (5). The purpose of these 
requirements is to evaluate progress towards the reasonable progress 
goal for each Class I area within the state and each Class I area 
outside the state that may be affected by emissions from within that 
state. Section 51.308(g)(1) and (2) apply to all states and require a 
description of the status of implementation of all measures included in 
a state's first implementation period regional haze plan and a summary 
of the emission reductions achieved through implementation of those 
measures. Section 51.308(g)(3) applies only to states with Class I 
areas within their borders and requires such states to assess current 
visibility conditions, changes in visibility relative to baseline 
(2000-2004) visibility conditions, and changes in visibility conditions 
relative to the period addressed in the first implementation period 
progress report. Section 51.308(g)(4) applies to all states and 
requires an analysis tracking changes in emissions of pollutants 
contributing to visibility impairment from all sources and sectors 
since the period addressed by the first implementation period progress 
report. This provision further specifies the year or years through 
which the analysis must extend depending on the type of source and the 
platform through which its emission information is reported. Finally, 
40 CFR 51.308(g)(5), which also applies to all states, requires an 
assessment of any significant changes in anthropogenic emissions within 
or outside the state have occurred since the period addressed by the 
first implementation period progress report, including whether such 
changes were anticipated and whether they have limited or impeded 
expected progress towards reducing emissions and improving visibility.
    The District's submission describes the status of the measures of 
the long-term strategy from the first implementation period and 
contains a summary of the emission reductions achieved by implementing 
those

[[Page 19810]]

measures.\86\ As a member of MANE-VU, the District considered the MANE-
VU Asks and adopted corresponding measures into its long-term strategy 
for the first implementation period.
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    \86\ Section 2.17 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    One of the MANE-VU Asks from the first implementation period was 
for states to address emissions from 167 EGUs across the middle and 
eastern United States. The District did not have any of those sources 
within its borders, and so did not incorporate any measures in response 
to this Ask into its plan. The District did have two units that met the 
eligibility requirements for BART, but the facility--the Pepco Benning 
Road Generation Station--took enforceable permit conditions to shut 
down both units in 2012 and therefore did not undergo BART 
determinations. The shutdown met another of the MANE-VU Asks, i.e., 
timely implementation of BART, by elimination of the would-be BART 
sources and their emissions from the inventory entirely. The emission 
reductions achieved through these source closures are summarized in the 
source retirement section of the submission.\87\ Lastly, in response to 
a MANE-VU Ask in 2015 the District promulgated a rule to reduce the 
sulfur content in commercial heating oil and to prohibit the use of 
heavy heating oils that contain high levels of sulfur. EPA approved 
this rule into the SIP on May 1, 2017. 82 FR 20270. The SO2 
and NOX emission reductions achieved by implementing this 
measure are presented in section 2.18 of the District's submission.
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    \87\ Section 2.7.3 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    EPA proposes to find that the District has met the requirements of 
40 CFR 51.308(g)(1) and (2) because its SIP submission describes the 
measures included in the long-term strategy from the first 
implementation period, as well as the status of their implementation 
and the emission reductions achieved through such implementation.
    Section 51.308(g)(3) requires states with Class I areas to report 
on the visibility conditions and changes at those areas. The District 
does not have any Class I areas and is not required to address this 
provision.
    Pursuant to 40 CFR 51.308(g)(4), the District provided a summary of 
emissions of SO2, NOX, PM10, and 
NH3 from all sources and activities, including from point, 
nonpoint, non-road mobile, and on-road mobile sources, for the time 
period from 2002 to 2014.\88\ The District explained that 2014 was the 
most recent year for which it had submitted emission estimates to 
fulfill the requirements of part 51 subpart A (the AERR).
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    \88\ See ``2017 National Emissions Inventory Data for the 
District of Columbia for Select Pollutants'' in the docket.
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    The emissions information submitted by the District indicates that 
SO2 emissions decreased over the 2002 through 2014 period. 
Due to source retirements, the District had zero tons of SO2 
emissions in 2014 from EGUs that report to EPA's AMPD and the 
submission indicates these emissions continued to be zero in 2016 and 
2017. SO2 emissions from non-AMPD point sources and 
nonpoint, non-road, and on-road sources all declined steadily from 2002 
to 2014.\89\
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    \89\ See section 2.20.3 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    Total NOX emissions have also declined from 2002 to 
2014, although not all categories have shown a consistent decrease. 
Reductions in NOX emissions from AMPD sources are primarily 
due to EGU retirements, while reductions in non-road and on-road 
NOX are due to a range of federal requirements for different 
types of engines and fuels.\90\
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    \90\ See section 2.20.2 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    Emissions of PM10 decreased overall from 2002 to 2014, 
with point, nonpoint, and non-road categories having lower emissions in 
2014 and on-road sources showing an increase in PM10 
emissions. Similarly, NH3 emissions in the District were 
lower overall in 2014 relative to 2002, although emissions from 
nonpoint sources do show an increase relative to the baseline.\91\
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    \91\ See section 2.20.1 of the DC DOEE 2019 Regional Haze SIP 
submission.
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    EPA is proposing to find that the District has satisfied the 
requirements of 40 CFR 51.308(g)(4) by providing emissions information 
for SO2, NOX, PM10, and NH3 
broken down by type of source. At the time of the District's SIP 
submission, the year of the most recent data submitted to NEI was 2014; 
therefore, the endpoint of the analysis of changes in emissions is 
2014. The District also provided SO2 and NOX data 
for sources that report to EPA's AMPD for 2016 and 2017.
    The District uses the emissions trend data to support the 
assessment that anthropogenic haze-causing pollutant emissions in the 
District have decreased during the reporting period and that changes in 
emissions have not limited or impeded progress for the regional haze 
program. EPA is proposing to find that the District has met the 
requirements of 40 CFR 51.308(g)(5).

I. Requirements for State and Federal Land Manager Coordination

    Section 51.308(i)(2)'s FLM consultation provision requires that a 
state must provide FLMs with an opportunity for consultation that is 
early enough in the state's policy analyses of its long-term strategy 
emission reduction obligation for the FLMs' input to meaningfully 
inform the state's decisions. If the consultation has taken place at 
least 120 days before a public hearing or public comment period, the 
opportunity for consultation will be deemed early enough, however, the 
opportunity for consultation must be provided at least sixty days 
before a public hearing or public comment period at the state level. 
Section 51.308(i)(2) also provides two substantive topics which FLMs 
must be provided an opportunity to discuss with states, and 40 CFR 
51.308(i)(3) requires states, in developing their implementation plans, 
to include a description of how they addressed FLMs' comments.
    The states in the MANE-VU RPO conducted FLM consultation early in 
the planning process concurrent with the state-to-state consultation 
that formed the basis of the RPO's decision making process. As part of 
the consultation, the FLMs were given the opportunity to review and 
comment on the technical documents developed by MANE-VU. The FLMs were 
invited to attend the intra- and inter-RPO consultations calls among 
states and at least one FLM representative was documented to have 
attended seven intra-RPO meetings and all inter-RPO meetings. The 
District participated in these consultation meetings and calls.\92\
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    \92\ See appendix 7 of the DC DOEE 2019 Regional Haze SIP 
submission, ``MANE-VU Regional Haze Consultation Summary (MANE-VU, 
July 2018).''
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    As part of this early engagement with the FLMs, in April 2018 the 
NPS sent letters to the MANE-VU states requesting that they consider 
evaluating particular sources for inclusion in their long-term 
strategies.\93\ The sources the NPS identified were selected based on a 
Q/d analysis it performed using cumulative NOX and 
SO2 emissions as the quantity variable Q and the distance to 
the nearest national park as the variable d. Sources with a Q/d greater 
than or equal to 1 were included on the 2018 NPS source list; the GSA 
Central Heating Plant met this threshold based on 2014 NEI data and its 
proximity to

[[Page 19811]]

Shenandoah National Park. The District noted that the NPS's methodology 
did not account for meteorological considerations such as wind 
direction, and that it disagreed with the NPS's conclusion that the GSA 
Central Heating Plant was reasonably anticipated to impair visibility 
at Shenandoah National Park. However, the District decided to respond 
to the consultation request by explaining the existing emission control 
measures at the facility. The District's explanation is summarized in 
section IV.E.2. of this document (addressing EPA's evaluation of the 
District's response to MANE-VU Ask 2).
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    \93\ See appendix 9 of the DC DOEE 2019 Regional Haze SIP 
submission, ``National Park Service Letter to MANE-VU (April 
2018).''
---------------------------------------------------------------------------

    On April 10, 2019, the District submitted a draft Regional Haze SIP 
to the U.S. Forest Service, the U.S. Fish and Wildlife Service, and the 
National Park Service for a 60-day review and comment period pursuant 
to 40 CFR 51.308(i)(2).\94\ The U.S. Forest Service commented that the 
draft it received was acceptable and no changes were needed.\95\ The 
National Park Service and the U.S. Fish and Wildlife Service did not 
provide comments during this consultation period. The District 
published its regional haze SIP in the District of Columbia Register 
for a 30-day comment period within the District on August 30, 2019. A 
public hearing was held on September 30, 2019. No comments were 
received. Consistent with 40 CFR 51.308(i)(2), the opportunity for FLM 
consultation took place more than 120 days prior to holding any public 
hearing.
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    \94\ See appendix 15 of the DC DOEE 2019 Regional Haze SIP 
submission, ``FLM Consultation Initiation Letter (April 2019).''
    \95\ See appendix 17 of the DC DOEE 2019 Regional Haze SIP 
submission, ``US Forest Service Consultation Response Letter (June 
2019).''
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    For the reasons stated above, EPA proposes to find that the 
District has met its requirements under 40 CFR 51.308(i) to consult 
with the FLMs on its regional haze SIP for the second implementation 
period. The District committed in its SIP to ongoing consultation with 
the FLMs on regional haze issues throughout the implementation period, 
consistent with the requirement of 40 CFR 51.308(i)(4).\96\
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    \96\ See section 2.28 of the DC DOEE 2019 Regional Haze SIP 
submission at 43.
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V. Error Correction

A. What is EPA's authority to correct errors in SIP rulemakings?

    Section 110(k)(6) of the CAA provides EPA with authority to make 
corrections to prior SIP actions that are subsequently found to be in 
error in the same manner as the prior action, and to do so without 
requiring any further submission from the state. This determination and 
the basis must be provided to the state and the public.

B. What rule is EPA proposing to correct?

    EPA approved the District's revision to the DC NOX RACT 
rule (20 DCMR 805) into the SIP on February 24, 2020 (85 FR 10295). The 
revisions to that rule amended the regulation to remove old provisions 
and replace them with new and/or more stringent regulations or controls 
for combustion turbines and associated heat recovery steam generators 
and duct burners and amended the applicability provisions of these 
regulations to include all combustion turbines and associated heat 
recovery steam generators and duct burners, among other related 
revisions and updates to the rule.
    After we finalized the rulemaking, EPA discovered that we had erred 
in identifying the particular sections of the DC NOX RACT 
rule for incorporation by reference into the DC SIP. In several 
instances, the substance of the District's revisions to its rule in 
section 805.4(a) and (b) were correctly represented and evaluated in 
EPA rulemaking, but were cited as being in section 805.1 of the DC 
NOX RACT rule. The District also submitted revisions to 
section 805.1(a) and 805.1(a)(2), which were appropriately discussed 
and correctly cited in the rulemaking (see 84 FR at 47918, September 
11, 2019). Throughout the prior rulemaking we incorrectly referred to 
section 805.4 as being section 805.1 in both in the narrative and 
regulatory table.

C. What action is EPA proposing?

    EPA is proposing to use our authority under CAA section 110(k)(6) 
to correct errors in the regulatory citation in our February 24, 2020 
final action on the DC NOX RACT rule and to codify this 
correction by revising the appropriate entries under 40 CFR 52.470 
(Identification of Plan). EPA previously proposed and took public 
comment on the substance of the DC NOX RACT rule and our 
evaluation thereof in the September 11, 2019 NPRM (84 FR 47914). 
Because this proposed rulemaking is limited to correcting our error in 
conflating the citations for 805.1 and 805.4, the scope of our present 
request for comment is limited to whether we are properly effectuating 
this correction and we will not be taking comment on the substance of 
the DC NOX RACT rule. Therefore, as required in CAA section 
110(k)(6), in the same manner as the prior action, EPA is proposing for 
public review and comment the correction to the citations of the 
provisions which were approved in the previous action. Specifically, we 
are proposing to amend the table in paragraph (c) of 40 CFR 52.470 to 
correctly reflect our approval of 20 DCMR sections 805.1(a), 
805.1(a)(2), 805.4(a) and 805.4(b), as described in our February 24, 
2020 final rule action. This proposal is separate from the proposal to 
approve the DC DOEE 2019 Regional Haze SIP submission, and as such EPA 
is taking public comments on the citation correction through this 
docket, but as a severable action.

VI. Proposed Action

    EPA is proposing to approve the revision to the District of 
Columbia SIP submitted by the District through DC DOEE on November 8, 
2019. EPA is proposing to approve the District's SIP submission as 
satisfying the regional haze requirements for the second implementation 
period.

VII. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the CAA and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely approves state law as meeting Federal requirements and 
does not impose additional requirements beyond those imposed by state 
law. For that reason, this proposed action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Public Law 104-4);
     Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or

[[Page 19812]]

safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 
1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, this proposed rulemaking, the District's regional haze 
state implementation plan for the second implementation period and 
correction for the RACT rule for major stationary sources of 
NOX, does not have tribal implications as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP 
is not approved to apply in Indian country located in the State, and 
EPA notes that it will not impose substantial direct costs on tribal 
governments or preempt tribal law.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Nitrogen dioxide, Ozone, Particulate matter, Sulfur oxides.

    Dated: April 5, 2021.
Diana Esher,
Acting Regional Administrator, Region III.
[FR Doc. 2021-07334 Filed 4-14-21; 8:45 am]
BILLING CODE 6560-50-P


