Document ID: EPA-R01-OAR-2023-0187-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: New Hampshire; Regional Haze State Implementation Plan for the Second Implementation Period
Posted Date: 2023-11-20T05:00Z

[Federal Register Volume 88, Number 222 (Monday, November 20, 2023)]
[Proposed Rules]
[Pages 80655-80680]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-25336]

=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R01-OAR-2023-0187; FRL-11554-03-R1]

Approval and Promulgation of Air Quality Implementation Plans; 
New Hampshire; Regional Haze State Implementation Plan for the Second 
Implementation Period

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve the Regional Haze State Implementation Plan (SIP) revision 
submitted by New Hampshire on May 5, 2022, as satisfying applicable 
requirements under the Clean Air Act (CAA) and EPA's Regional Haze Rule 
for the program's second implementation period. New Hampshire'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, including regional 
haze, in mandatory Class I Federal areas. The SIP submission also 
addresses other applicable requirements for the second implementation 
period of the regional haze program. The EPA is taking this action 
pursuant to sections 110 and 169A of the Clean Air Act.

DATES: Written comments must be received on or before December 20, 
2023.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA- at 
https://www.regulations.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, the EPA may publish any comment received to its 
public docket. Do not submit electronically any information you 
consider to be confidential business information (CBI) or other 
information whose disclosure is restricted by statute. Multimedia 
submissions (audio, video, etc.) must be accompanied by a written 
comment. The written comment is considered the official comment and 
should include discussion of all points you wish to make. The EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (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: Eric Rackauskas, Air Quality Branch, 
U.S. Environmental Protection Agency, EPA Region 1, 5 Post Office 
Square--Suite 100, (Mail code 5-MI), Boston, MA 02109-3912, tel. (617) 
918-1628, email [email protected].

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. What action is the 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
    C. Long-Term Strategy for Regional Haze
    D. Reasonable Progress Goals
    E. Monitoring Strategy and Other State 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. The EPA's Evaluation of New Hampshire's Regional Haze Submission 
for the Second Implementation Period
    A. Background on New Hampshire's First Implementation Period SIP 
Submission
    B. New Hampshire's Second Implementation Period SIP Submission 
and the EPA's Evaluation
    C. Identification of Class I Areas
    D. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the Uniform Rate of Progress
    E. Long-Term Strategy for Regional Haze
    a. New Hampshire's Response to the Six MANE-VU Asks

[[Page 80656]]

    b. The EPA's Evaluation of New Hampshire's Response to the Six 
MANE-VU Asks and Compliance With Sec.  51.308(f)(2)(i)
    c. 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. Proposed Action
VI. Incorporation by Reference
VII. Statutory and Executive Order Reviews

I. What action is the EPA proposing?

    On May 5, 2022, supplemented on September 21, 2023,\1\ the New 
Hampshire Department of Environmental Services (NHDES) submitted a 
revision to its SIP to address regional haze for the second 
implementation period. NHDES 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. The EPA is proposing to find 
that the New Hampshire regional haze SIP submission for the second 
implementation period meets the applicable statutory and regulatory 
requirements and thus proposes to approve New Hampshire's submission 
into its SIP.
---------------------------------------------------------------------------

    \1\ NH included a corrected Appendix W in a supplemental 
submission on September 21, 2023.
---------------------------------------------------------------------------

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.\2\ CAA 169A. 
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.'' CAA 169A(a)(1). The CAA further directs the EPA to 
promulgate regulations to assure reasonable progress toward meeting 
this national goal. CAA 169A(a)(4). On December 2, 1980, the 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, December 2, 1980). These regulations, 
codified at 40 CFR 51.300 through 51.307, represented the first phase 
of the 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. CAA 169B. The 
EPA promulgated the Regional Haze Rule (RHR), codified at 40 CFR 
51.308,\3\ on July 1, 1999. (64 FR 35714, July 1, 1999). These regional 
haze regulations are a central component of the EPA's comprehensive 
visibility protection program for Class I areas.
---------------------------------------------------------------------------

    \2\ 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. CAA 
162(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.
    \3\ In addition to the generally applicable regional haze 
provisions at 40 CFR 51.308, the 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.
---------------------------------------------------------------------------

    Regional haze is visibility impairment that is produced by a 
multitude of anthropogenic 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), nitrogen oxides (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.\4\
---------------------------------------------------------------------------

    \4\ There are several ways to measure the amount of visibility 
impairment, i.e., haze. One such measurement is the deciview, which 
is the principal 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 (b\ext\) is a metric used to for 
expressing visibility and is measured in inverse megameters 
(Mm-1). The EPA's Guidance on Regional Haze 
State Implementation Plans for the Second Implementation Period 
(``2019 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, https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period, The EPA Office of Air Quality Planning and 
Standards, Research Triangle Park (August 20, 2019). The formula for 
the deciview is 10 ln (b\ext\)/10 Mm-1). 40 
CFR 51.301.
---------------------------------------------------------------------------

    To address regional haze visibility impairment, the 1999 RHR 
established an iterative planning process that requires both 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 such impairment. CAA 169A(b)(2); \5\ see also 40 CFR 
51.308(b), (f) (establishing submission dates for iterative regional 
haze SIP revisions); (64 FR at 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,'' CAA 169A(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). CAA 169A(b)(2)(A); 40 CFR 
51.308(d), (e). States' first regional haze SIPs were due by December 
17, 2007, 40 CFR 51.308(b), with subsequent SIP submissions containing 
updated long-term strategies originally due July 31, 2018, and every 
ten years thereafter. (64 FR at 35768, July 1, 1999). The 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.\6\ Id. at 
35721.
---------------------------------------------------------------------------

    \5\ The RHR expresses the statutory requirement for states to 
submit plans addressing out-of-state class I areas by providing that 
states must address visibility impairment ``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(d), (f).
    \6\ In addition to each of the fifty states, the EPA also 
concluded that the Virgin Islands and District of Columbia must also 
submit regional haze SIPs because they either contain a Class I area 
or contain sources whose emissions are reasonably anticipated to 
contribute regional haze in a Class I area. See 40 CFR 51.300(b), 
(d)(3).
---------------------------------------------------------------------------

    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 making 
reasonable progress toward the national visibility goal, of which BART 
is one component. 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

[[Page 80657]]

containing Class I areas establish reasonable progress goals (RPGs) 
that are measured in deciviews and reflect the anticipated visibility 
conditions at the end of the implementation period including from 
implementation of states' long-term strategies. 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. CAA 169A(g)(1); 40 CFR 
51.308(d)(1).
    States were also required to calculate baseline (using the five-
year period of 2000-2004) 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.\7\ 40 CFR 
51.308(d)(1)(i)(B), (d)(2). The 1999 RHR also provided that States' 
long-term strategies must include the ``enforceable emissions 
limitations, compliance, schedules, and other measures as necessary to 
achieve the reasonable progress goals.'' 40 CFR 51.308(d)(3). In 
establishing their long-term strategies, states are required to consult 
with other states that also contribute to visibility impairment in a 
given Class I area and include all measures necessary to obtain their 
shares of the emission reductions needed to meet the RPGs. 40 CFR 
51.308(d)(3)(i), (ii). Section 51.308(d) also contains seven additional 
factors states must consider in formulating their long-term strategies, 
40 CFR 51.308(d)(3)(v), as well as provisions governing monitoring and 
other implementation plan requirements. 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), (h)--and to consult with the Federal Land Manager(s) 
\8\ (FLMs) responsible for each Class I area according to the 
requirements in CAA 169A(d) and 40 CFR 51.308(i).
---------------------------------------------------------------------------

    \7\ 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 
start point for the URP analysis is 2004 and the endpoint 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 60 years, or 
2064 (60 years from the baseline starting point of 2004). However, 
EPA did not establish 2064 as the year by which the national goal 
must be reached. 64 FR at 35731-32. 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 3078, 3084, January 10, 2017).
    \8\ The 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 Commission.'' 40 CFR 51.301.
---------------------------------------------------------------------------

    On January 10, 2017, the EPA promulgated revisions to the RHR, (82 
FR 3078, January 10, 2017), that apply for the second and subsequent 
implementation periods. The 2017 rulemaking 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 rulemaking (referred to here as the 2017 RHR Revisions) are 
codified at 40 CFR 51.308(f). Among other changes, 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. The 
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.
    The 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, the EPA issued ``Guidance on Regional Haze State 
Implementation Plans for the Second Implementation Period'' (``2019 
Guidance'').\9\ On July 8, 2021, the EPA issued a memorandum containing 
``Clarifications Regarding Regional Haze State Implementation Plans for 
the Second Implementation Period'' (``2021 Clarifications Memo'').\10\ 
Additionally, the 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'' (``2018 Visibility Tracking 
Guidance''),\11\ 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 (``2020 
Data Completeness Memo'').\12\
---------------------------------------------------------------------------

    \9\ Guidance on Regional Haze State Implementation Plans for the 
Second Implementation Period. https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period The EPA Office of Air Quality Planning and 
Standards, Research Triangle Park (August 20, 2019).
    \10\ Clarifications Regarding Regional Haze State Implementation 
Plans for the Second Implementation Period. https://www.epa.gov/system/files/documents/2021-07/clarifications-regarding-regional-haze-state-implementation-plans-for-the-second-implementation-period.pdf. The EPA Office of Air Quality Planning and Standards, 
Research Triangle Park (July 8, 2021).
    \11\ Technical Guidance on Tracking Visibility Progress for the 
Second Implementation Period of the Regional Haze Program. https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional The EPA Office of Air 
Quality Planning and Standards, Research Triangle Park. (December 
20, 2018).
    \12\ 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. https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program The EPA 
Office of Air Quality Planning and Standards, Research Triangle Park 
(June 3, 2020).
---------------------------------------------------------------------------

    As previously explained in the 2021 Clarifications Memo, EPA 
intends the second implementation period of the regional haze program 
to secure

[[Page 80658]]

meaningful reductions in visibility impairing pollutants that build on 
the significant progress states have achieved to date. The Agency also 
recognizes that analyses regarding reasonable progress are state-
specific and that, based on states' and sources' individual 
circumstances, what constitutes reasonable reductions in visibility 
impairing pollutants will vary from state-to-state. While there exist 
many opportunities for states to leverage both ongoing and upcoming 
emission reductions under other CAA programs, the Agency expects states 
to undertake rigorous reasonable progress analyses that identify 
further opportunities to advance the national visibility goal 
consistent with the statutory and regulatory requirements. See 
generally 2021 Clarifications Memo. This is consistent with Congress's 
determination that a visibility protection program is needed in 
addition to the CAA's National Ambient Air Quality Standards and 
Prevention of Significant Deterioration programs, as further emission 
reductions may be necessary to adequately protect visibility in Class I 
areas throughout the country.\13\
---------------------------------------------------------------------------

    \13\ See, e.g., H.R. Rep No. 95-294 at 205 (``In determining how 
to best remedy the growing visibility problem in these areas of 
great scenic importance, the committee realizes that as a matter of 
equity, the national ambient air quality standards cannot be revised 
to adequately protect visibility in all areas of the country.''), 
(``the mandatory class I increments of [the PSD program] do not 
adequately protect visibility in class I areas'').
---------------------------------------------------------------------------

B. Roles of Agencies in Addressing Regional Haze

    Because the air pollutants and pollution affecting visibility in 
Class I 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),\14\ 
which include representation from state and tribal governments, the 
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.
---------------------------------------------------------------------------

    \14\ RPOs are sometimes also referred to as ``multi-
jurisdictional organizations,'' or MJOs. For the purposes of this 
notice, the terms RPO and MJO are synonymous.
---------------------------------------------------------------------------

    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 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

    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 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. CAA 169A(b)(2)(B). To this end, Sec.  51.308(f) lays 
out the process by which states determine what constitutes their long-
term strategies, with the order of the requirements in Sec.  
51.308(f)(1) through (f)(3) generally mirroring the order of the steps 
in the reasonable progress analysis \15\ and (f)(4) through (f)(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), 
(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. A reasonable 
progress determination is based on applying the four factors in CAA 
section 169A(g)(1) to sources of visibility-impairing pollutants that 
the state has selected to assess for controls for the second 
implementation period. See 40 CFR 51.308(f)(2). Additionally, as 
further explained below, the RHR at 40 CFR 51.308(f)(2)(iv) separately 
provides five ``additional factors'' \16\ that states must consider in 
developing their long-term strategies. A state evaluates potential 
emission reduction measures for those selected sources and determines 
which are necessary to make reasonable progress. Those measures are 
then incorporated into the state's long-term strategy. After a state 
has developed its long-term strategy, 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 URP to ensure that progress is being made 
towards the statutory goal of preventing any future and remedying any 
existing anthropogenic visibility impairment in Class I areas. 40 CFR 
51.308(f)(2)-(3).
---------------------------------------------------------------------------

    \15\ 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 51.308(d), ``tracked the actual planning 
sequence.'' (82 FR 3091, January 10, 2017).
    \16\ The five ``additional factors'' for consideration in 
section 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.
---------------------------------------------------------------------------

    In addition to satisfying the requirements at 40 CFR 51.308(f) 
related to reasonable progress, the regional haze SIP revisions for the 
second implementation period must address the requirements in Sec.  
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

[[Page 80659]]

apply to all visibility protection SIPs and SIP revisions. 40 CFR 
51.308(i).
    A state must submit its regional haze SIP and subsequent SIP 
revisions to the EPA according to the requirements applicable to all 
SIP revisions under the CAA and EPA's regulations. See CAA 169(b)(2); 
CAA 110(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 the 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. CAA 110(c)(1).

A. Identification of Class I Areas

    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, the EPA determined that all states contribute to visibility 
impairment in at least one Class I area, 64 FR at 35720-22, 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.
    A state must determine which Class I areas must be addressed by its 
SIP by evaluating the total emissions of visibility impairing 
pollutants from all sources within the state. While the RHR does not 
require this evaluation 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. In addition, 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

    As part of assessing whether a SIP submission for the second 
implementation period is providing for reasonable progress towards the 
national visibility goal, the RHR contains requirements in Sec.  
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 \17\ 
provides recommendations to assist states in satisfying their 
obligations under Sec.  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 and prescribed fires. 
See 82 FR at 3103-05.
---------------------------------------------------------------------------

    \17\ The 2018 Visibility Tracking Guidance references and relies 
on parts of the 2003 Tracking Guidance: ``Guidance for Tracking 
Progress Under the Regional Haze Rule,'' which can be found at 
https://www3.epa.gov/ttnamti1/files/ambient/visible/tracking.pdf.
---------------------------------------------------------------------------

    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).\18\ 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), (iii). States must also 
calculate natural visibility conditions for the clearest and most 
impaired days,\19\ 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.
---------------------------------------------------------------------------

    \18\ This notice also refers to the 20% clearest and 20% most 
anthropogenically impaired days as the ``clearest'' and ``most 
impaired'' or ``most anthropogenically impaired'' days, 
respectively.
    \19\ 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: 
``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.''
---------------------------------------------------------------------------

    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.\20\ Additionally, in the 2017 RHR Revisions, the EPA 
provided states the option of proposing to adjust the endpoint 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 the 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 footnote 116.
---------------------------------------------------------------------------

    \20\ 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.
---------------------------------------------------------------------------

    EPA's 2018 Visibility Tracking Guidance can be used to help satisfy 
the 40 CFR 51.308(f)(1) requirements, including in developing 
information on baseline, current, and natural visibility conditions, 
and in making optional adjustments to the URP. In addition, the 2020 
Data Completeness Memo provides recommendations on the data 
completeness language referenced in Sec.  51.308(f)(1)(i) and provides 
updated natural conditions estimates for each Class I area.

C. Long-Term Strategy for Regional Haze

    The core component of a regional haze SIP submission is a long-term

[[Page 80660]]

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 
(f)(2)(i) through (iv).'' 40 CFR 51.308(f)(2). The amount of progress 
that is ``reasonable progress'' is based on 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 emission reduction measures that a particular source or group of 
sources needs to implement in order to make reasonable progress towards 
the national visibility goal. See 40 CFR 51.308(f)(2)(i). Emission 
reduction measures that are necessary to make reasonable progress may 
be either new, additional control measures for a source, or they may be 
the existing emission reduction measures that a source is already 
implementing. See 2019 Guidance at 43; 2021 Clarifications Memo at 8-
10. Such measures must be represented by ``enforceable emissions 
limitations, compliance schedules, and other measures'' (i.e., any 
additional compliance tools) in a state's long-term strategy in its 
SIP. 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 for potential four-factor control 
analysis. 40 CFR 51.308(f)(2)(i). A threshold question at this step is 
which visibility impairing pollutants will be analyzed. As EPA 
previously explained, consistent with the first implementation period, 
EPA generally expects that each state will analyze at least 
SO2 and NOX in selecting sources and determining 
control measures. See 2019 Guidance at 12, 2021 Clarifications Memo at 
4. A state that chooses not to consider at least these two pollutants 
should demonstrate why such consideration would be unreasonable. 2021 
Clarifications Memo at 4.
    While states have the option to analyze all sources, the 2019 
Guidance explains that ``an analysis of control measures is not 
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. However, given that source 
selection is the basis of all subsequent control determinations, a 
reasonable source selection process ``should be designed and conducted 
to ensure that source selection results in a set of pollutants and 
sources the evaluation of which has the potential to meaningfully 
reduce their contributions to visibility impairment.'' 2021 
Clarifications Memo at 3.
    EPA explained in the 2021 Clarifications Memo that each state has 
an obligation to submit a long-term strategy that addresses the 
regional haze visibility impairment that results from emissions from 
within that state. Thus, source selection should focus on the in-state 
contribution to visibility impairment and be designed to capture a 
meaningful portion of the state's total contribution to visibility 
impairment in Class I areas. A state should not decline to select its 
largest in-state sources on the basis that there are even larger out-
of-state contributors. 2021 Clarifications Memo at 4.\21\
---------------------------------------------------------------------------

    \21\ Similarly, in responding to comments on the 2017 RHR 
Revisions EPA explained that ``[a] state should not fail to address 
its many relatively low-impact sources merely because it only has 
such sources and another state has even more low-impact sources and/
or some high impact sources.'' Responses to Comments on Protection 
of Visibility: Amendments to Requirements for State Plans; Proposed 
Rule (81 FR 26942, May 4, 2016) at 87-88.
---------------------------------------------------------------------------

    Thus, while states have discretion to choose any source selection 
methodology that is reasonable, whatever choices they make should be 
reasonably explained. 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, must also be appropriately documented, as 
required by 40 CFR 51.308(f)(2)(iii).
    Once a state has selected the set of sources, the next step is to 
determine the emissions reduction measures for those sources that are 
necessary to make reasonable progress for the second implementation 
period.\22\ This is accomplished by considering the four factors--``the 
costs of compliance, the time necessary for compliance, and the energy 
and nonair quality environmental impacts of compliance, and the 
remaining useful life of any existing source subject to such 
requirements.'' CAA 169A(g)(1). The 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 at 3091. Thus, 
for each source it has selected for four-factor analysis,\23\ 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.
---------------------------------------------------------------------------

    \22\ The CAA provides that, ``[i]n determining reasonable 
progress there shall be taken into consideration'' the four 
statutory factors. CAA 169A(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, on-the-books, or on-the-way rules and measures for 
sources not selected for four-factor analysis for the second 
planning period.
    \23\ ``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 at 
3088. However, not all approaches to grouping sources for four-
factor analysis are necessarily reasonable; the reasonableness of 
grouping sources in any particular instance will depend on the 
circumstances and the manner in which grouping is conducted. If it 
is feasible to establish and enforce different requirements for 
sources or subgroups of sources, and if relevant factors can be 
quantified for those sources or subgroups, then states should make a 
separate reasonable progress determination for each source or 
subgroup. 2021 Clarifications Memo at 7-8.
---------------------------------------------------------------------------

    EPA's 2021 Clarifications Memo provides further guidance on what 
constitutes a reasonable set of control options for consideration: ``A 
reasonable four-factor analysis will consider the full range of 
potentially reasonable options for reducing emissions.'' 2021

[[Page 80661]]

Clarifications Memo at 7. In addition to add-on controls and other 
retrofits (i.e., new emission reduction measures for sources), EPA 
explained that states should generally analyze efficiency improvements 
for sources' existing measures as control options in their four-factor 
analyses, as in many cases such improvements are reasonable given that 
they typically involve only additional operation and maintenance costs. 
Additionally, the 2021 Clarifications Memo provides that states that 
have assumed a higher emission rate than a source has achieved or could 
potentially achieve using its existing measures should also consider 
lower emission rates as potential control options. That is, a state 
should consider a source's recent actual and projected emission rates 
to determine if it could reasonably attain lower emission rates with 
its existing measures. If so, the state should analyze the lower 
emission rate as a control option for reducing emissions. 2021 
Clarifications Memo at 7. The EPA's recommendations to analyze 
potential efficiency improvements and achievable lower emission rates 
apply to both sources that have been selected for four-factor analysis 
and those that have forgone a four-factor analysis on the basis of 
existing ``effective controls.'' See 2021 Clarifications Memo at 5, 10.
    After identifying a reasonable set of potential control options for 
the sources it has selected, a state then collects information on the 
four factors with regard to each option identified. The 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 additional factor alongside the four statutory 
factors.\24\ 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. The 2021 Clarifications Memo contains 
further guidance on how states can reasonably consider modeled 
visibility impacts or benefits in the context of a four-factor 
analysis. 2021 Clarifications Memo at 12-13, 14-15. Specifically, EPA 
explained that while visibility can reasonably be used when comparing 
and choosing between multiple reasonable control options, it should not 
be used to summarily reject controls that are reasonable given the four 
statutory factors. 2021 Clarifications Memo at 13. Ultimately, while 
states have discretion to reasonably weigh the factors and to determine 
what level of control is needed, Sec.  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.''
---------------------------------------------------------------------------

    \24\ 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.
---------------------------------------------------------------------------

    As explained above, Sec.  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. 
Pursuant to Sec.  51.308(f)(2), measures that are necessary to make 
reasonable progress towards the national visibility goal must be 
included in a state's long-term strategy and in its SIP.\25\ If the 
outcome of a four-factor analysis is a new, additional emission 
reduction measure for a source, that new measure is necessary to make 
reasonable progress towards remedying existing anthropogenic visibility 
impairment and must be included in the SIP. If the outcome of a four-
factor analysis is that no new measures are reasonable for a source, 
continued implementation of the source's existing measures is generally 
necessary to prevent future emission increases and thus to make 
reasonable progress towards the second part of the national visibility 
goal: preventing future anthropogenic visibility impairment. See CAA 
169A(a)(1). That is, when the result of a four-factor analysis is that 
no new measures are necessary to make reasonable progress, the source's 
existing measures are generally necessary to make reasonable progress 
and must be included in the SIP. However, there may be circumstances in 
which a state can demonstrate that a source's existing measures are not 
necessary to make reasonable progress. Specifically, if a state can 
demonstrate that a source will continue to implement its existing 
measures and will not increase its emission rate, it may not be 
necessary to have those measures in the long-term strategy in order to 
prevent future emission increases and future visibility impairment. 
EPA's 2021 Clarifications Memo provides further explanation and 
guidance on how states may demonstrate that a source's existing 
measures are not necessary to make reasonable progress. See 2021 
Clarifications Memo at 8-10. If the state can make such a 
demonstration, it need not include a source's existing measures in the 
long-term strategy or its SIP.
---------------------------------------------------------------------------

    \25\ States may choose to, but are not required to, include 
measures in their long-term strategies beyond just the emission 
reduction measures that are necessary for reasonable progress. See 
2021 Clarifications Memo at 16. For example, states with smoke 
management programs may choose to submit their smoke management 
plans to EPA for inclusion in their SIPs but are not required to do 
so. See, e.g., 82 FR at 3108-09 (requirement to consider smoke 
management practices and smoke management programs under 40 CFR 
51.308(f)(2)(iv) does not require states to adopt such practices or 
programs into their SIPs, although they may elect to do so).
---------------------------------------------------------------------------

    As with source selection, the characterization of information on 
each of the factors is also subject to the documentation requirement in 
Sec.  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, Sec.  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 the 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 output has 
been approved by all state participants. In addition to the explicit 
regulatory requirement to document the technical basis of their 
reasonable progress determinations, states are also subject to the 
general principle that those determinations must be reasonably moored 
to the statute.\26\ That is, a state's decisions about the emission

[[Page 80662]]

reduction measures that are necessary to make reasonable progress must 
be consistent with the statutory goal of remedying existing and 
preventing future visibility impairment.
---------------------------------------------------------------------------

    \26\ See Arizona ex rel. Darwin v. U.S. EPA, 815 F.3d 519, 531 
(9th Cir. 2016); Nebraska v. U.S. EPA, 812 F.3d 662, 668 (8th Cir. 
2016); North Dakota v. EPA, 730 F.3d 750, 761 (8th Cir. 2013); 
Oklahoma v. EPA, 723 F.3d 1201, 1206, 1208-10 (10th Cir. 2013); cf. 
also Alaska Dep't of Envtl. Conservation v. EPA, 540 U.S. 461, 485, 
490 (2004); Nat'l Parks Conservation Ass'n v. EPA, 803 F.3d 151, 165 
(3d Cir. 2015);.
---------------------------------------------------------------------------

    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 51.3108(f)(2)(iv) separately 
provides five ``additional factors'' \27\ that states must consider in 
developing their long-term strategies: (1) Emission reductions due to 
ongoing air pollution control programs, including measures to address 
reasonably attributable visibility impairment; (2) measures to reduce 
the impacts of construction activities; (3) source retirement and 
replacement schedules; (4) basic smoke management practices for 
prescribed fire used for agricultural and wildland vegetation 
management purposes and smoke management programs; and (5) the 
anticipated net effect on visibility due to projected changes in point, 
area, and mobile source emissions over the period addressed by the 
long-term strategy. The 2019 Guidance provides 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. EPA provided further guidance on the five additional 
factors in the 2021 Clarifications Memo, explaining that a state should 
generally not reject cost-effective and otherwise reasonable controls 
merely because there have been emission reductions since the first 
planning period owing to other ongoing air pollution control programs 
or merely because visibility is otherwise projected to improve at Class 
I areas. Additionally, states generally should not rely on these 
additional factors to summarily assert that the state has already made 
sufficient progress and, therefore, no sources need to be selected or 
no new controls are needed regardless of the outcome of four-factor 
analyses. 2021 Clarifications Memo at 13.
---------------------------------------------------------------------------

    \27\ The five ``additional factors'' for consideration in 
section 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, Sec.  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. 
Consultation allows 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. 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). 
Additionally, the RHR requires that states that contribute to 
visibility impairment at the same Class I area consider the emission 
reduction measures the other contributing states have identified as 
being necessary to make reasonable progress for their own sources. 40 
CFR 51.308(f)(2)(ii)(B). 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). The 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. See 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. Their primary purpose is to assist the 
public and the 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)-(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 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 emission reduction 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.\28\ The RPGs 
also account for the projected impacts of implementing other CAA 
requirements, including non-SIP based requirements. Because RPGs are 
the modeled result of the measures in states' long-term strategies (as 
well as other measures required under the CAA), they cannot be 
determined before states have conducted their four-factor analyses and 
determined the control measures that are necessary to make reasonable 
progress. See 2021 Clarifications Memo at 6.
---------------------------------------------------------------------------

    \28\ RPGs are intended to reflect the projected impacts of the 
measures all contributing states include in their long-term 
strategies. However, due to the timing of analyses and of control 
determinations by other states, other on-going emissions changes, a 
particular state's RPGs may not reflect all control measures and 
emissions reductions that are expected to occur by the end of the 
implementation period. The 2019 Guidance provides recommendations 
for addressing the timing of RPG calculations when states are 
developing their long-term strategies on disparate schedules, as 
well as for adjusting RPGs using a post-modeling approach. 2019 
Guidance at 47-48.
---------------------------------------------------------------------------

    For the second 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, Sec.  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 conditions on the most impaired days that are better 
than the baseline period and show 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 at 3097-98.
    So that RPGs may also serve as a metric for assessing the amount of 
progress a state is making towards the

[[Page 80663]]

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 state that contributes to visibility impairment in 
the Class I area 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, 2019 Guidance, and 2021 Clarifications Memo 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 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. The URP is a planning metric used to gauge the amount of 
progress made thus far and the amount left before reaching natural 
visibility conditions. However, the URP is not based on consideration 
of the four statutory factors and therefore cannot answer the question 
of whether the amount of progress being made in any particular 
implementation period is ``reasonable progress.'' See 82 FR at 3093, 
3099-3100; 2019 Guidance at 22; 2021 Clarifications Memo at 15-16.

E. Monitoring Strategy and Other State 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 the 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 is 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), (f)(6)(i), 
(f)(6)(iv). The IMPROVE monitoring data is used to determine the 20% 
most anthropogenically impaired and 20% 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), (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.\29\ 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.\30\
---------------------------------------------------------------------------

    \29\ See ``Step 8: Additional requirements for regional haze 
SIPs'' in 2019 Regional Haze Guidance at 55.
    \30\ 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 Sec.  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.'' \31\ Under this 
provision, if the 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.
---------------------------------------------------------------------------

    \31\ 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 paragraphs 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 the 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 at 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).

[[Page 80664]]

    A core component of the progress report requirements is an 
assessment of changes in visibility conditions on the clearest and most 
impaired days. For second implementation period progress reports, Sec.  
51.308(g)(3) requires states with Class I areas within their borders to 
first determine current visibility conditions for each area on the most 
impaired and clearest days, 40 CFR 51.308(g)(3)(i)(B), 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)(B). States must also assess the 
changes in visibility impairment for the most impaired and clearest 
days since they submitted their first implementation period progress 
reports. See 40 CFR 51.308(g)(3)(iii)(B), (f)(5). Since different 
states submitted their first implementation period progress reports at 
different times, the starting point for this assessment will vary state 
by state.
    Similarly, states must provide analyses tracking the change in 
emissions of pollutants contributing to visibility impairment from all 
sources and activities within the state over the period since they 
submitted their first implementation period progress reports. See 40 
CFR 51.308(g)(4), (f)(5). Changes in emissions should be identified by 
the type of source or activity. 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 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 notice 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 the 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 the 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. The EPA's Evaluation of New Hampshire's Regional Haze Submission 
for the Second Implementation Period

A. Background on New Hampshire's First Implementation Period SIP 
Submission

    NHDES submitted its regional haze SIP for the first implementation 
period to the EPA on January 9, 2010, and supplemented it on January 
14, 2011, and August 14, 2011. The EPA approved New Hampshire's first 
implementation period regional haze SIP submission on August 22, 2012 
(77 FR 50602). Pursuant to 40 CFR 51.308(g), New Hampshire was also 
responsible for submitting a five-year progress report as a SIP 
revision for the first implementation period, which it did on December 
16, 2014. The EPA approved the progress report into the New Hampshire 
SIP on October 12, 2016 (81 FR 70360).

B. New Hampshire's Second Implementation Period SIP Submission and the 
EPA's Evaluation

    In accordance with CAA sections 169A and the RHR at 40 CFR 
51.308(f), on May 5, 2022, NHDES submitted a revision to the New 
Hampshire SIP to address its regional haze obligations for the second 
implementation period, which runs through 2028. The New Hampshire 
submission also included the revised New Hampshire's Code of 
Administrative Rules Env-A 2300, ``Mitigation of Regional Haze,'' which 
contains updated emissions limits for certain facilities located in the 
State. New Hampshire made a draft Regional Haze SIP submission 
available for public comment on November 4, 2019, with a second notice 
made available for public comment on December 10, 2021. A public 
hearing was also held on February 23, 2022. NHDES has included the 
public comments and its responses to those comments in the submission.
    The following sections describe New Hampshire's SIP submission, 
including analyses conducted by MANE-VU and New Hampshire's 
determinations based on those analyses, New Hampshire's assessment of 
progress made since the first implementation period in reducing 
emissions of visibility impairing pollutants, and the visibility 
improvement progress at its Class I areas and nearby Class I areas. 
This notice also contains EPA's evaluation of New Hampshire'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 169A(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 implements this statutory requirement 
at 40 CFR 51.308(f), 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.
    The 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

[[Page 80665]]

low triggering threshold' in determining which States should submit 
SIPs for regional haze.'' 64 FR at 35721. In concluding that each of 
the contiguous 48 states and the District of Columbia meet this 
threshold,\32\ the 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 visibility impairment, the 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, the 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 at 
3094.
---------------------------------------------------------------------------

    \32\ 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 at 35721. Hawaii, Alaska, and the U.S. Virgin 
Islands must also submit regional haze SIPs because they contain 
Class I areas.
---------------------------------------------------------------------------

    New Hampshire has two mandatory Class I Federal areas within its 
borders, the Great Gulf Wilderness Area and the Presidential Range-Dry 
River Wilderness Area. Visibility monitoring in these areas is 
accomplished with instruments located at a single site at Camp Dodge. 
This monitoring station represents both Class 1 wilderness areas, and 
for this reason, both of New Hampshire's Federal Class I areas are 
often referred to collectively as simply the Great Gulf Wilderness. For 
the second implementation period, MANE-VU performed technical analyses 
\33\ to help assess source and state-level contributions to visibility 
impairment and the need for interstate consultation. 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.'' 
\34\ Similar to metrics used in the first implementation period,\35\ 
MANE-VU used a greater than 2 percent of sulfate plus nitrate emissions 
contribution criteria to determine whether emissions from individual 
jurisdictions within the region affected visibility in any Class I 
areas. The MANE-VU analyses for the second implementation period used a 
combination of data analysis techniques, including emissions data, 
distance from Class I areas, wind trajectories, and CALPUFF dispersion 
modeling. Although many of the analyses focused only on SO2 
emissions and resultant particulate sulfate contributions to visibility 
impairment, some also incorporated NOX emissions to estimate 
particulate nitrate contributions.
---------------------------------------------------------------------------

    \33\ The contribution assessment methodologies for MANE-VU Class 
I areas are summarized in appendix E of the docket. ``Selection of 
States for MANE-VU Regional Haze Consultation (2018).''
    \34\ Id.
    \35\ See docket EPA-R01-OAR-2023-0187 for MANE-VU supporting 
materials.
---------------------------------------------------------------------------

    One MANE-VU analysis used for contribution assessment was CALPUFF 
air dispersion modeling. The CALPUFF model was used to estimate sulfate 
and nitrate formation and transport in MANE-VU and nearby regions 
originating from large electric generating unit (EGU) point sources and 
other large industrial and institutional sources in the eastern and 
central United States. Information from an initial round of CALPUFF 
modeling was collated for the 444 EGUs that were determined to warrant 
further scrutiny based on their emissions of SO2 and 
NOX. The list of EGUs was based on an enhanced ``Q/d'' 
analysis \36\ that considered recent SO2 emissions in the 
eastern United States and an analysis that adjusted previous 2002 MANE-
VU CALPUFF modeling by applying a ratio of 2011 to 2002 SO2 
emissions. This list of sources was then enhanced by including the top 
five SO2 and NOx emission sources for 2011 for each state 
included in the modeling domain. A total of 311 EGU stacks (as opposed 
to individual units) were included in the CALPUFF modeling analysis. 
Initial information was also collected on the 50 industrial and 
institutional sources that, according to 2011 Q/d analysis, contributed 
the most to visibility impact in each Class I area. The ultimate 
CALPUFF modeling run included a total of 311 EGU stacks and 82 
industrial facilities. The summary report for the CALPUFF modeling 
included the top 10 most impacting EGUs and the top 5 most impacting 
industrial/institutional 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.\37\
---------------------------------------------------------------------------

    \36\ ``Q/d'' is emissions (Q) in tons per year, typically of one 
or a combination of visibility-impairing pollutants, divided by 
distance to a class I area (d) in kilometers. The resulting ratio is 
commonly used as a metric to assess a source's potential visibility 
impacts on a particular class I area.
    \37\ See appendix C in the Docket, ``2016 MANE-VU Source 
Contribution Modeling Report, CALPUFF Modeling of Large Electrical 
Generating Units and Industrial Sources'' and appendix D ``MANE-VU 
TSC'', (April 2016) and ``MANE-VU Updated Q/d*C Contribution 
Assessment.''
---------------------------------------------------------------------------

    The CALPUFF modeling results identified GSP Merrimack (units 1 and 
2) and Newington as New Hampshire's EGU emissions sources impacting 
Great Gulf above a 1 Mm-1 light extinction impact threshold. 
NHDES also performed CALPUFF screening on several other New Hampshire 
emission sources. The selection of emission units for modeling was 
based on the MANE-VU EGU and peaking unit criteria, the MANE-VU 
industrial, commercial, and institutional (ICI) facility criteria, and 
requests from EPA and the National Park Service through consultation. 
The New Hampshire sources which had maximum estimated visibility 
extinction above 1 Mm-1 at federal Class I areas were 
included in the list of New Hampshire sources for further analysis.\38\
---------------------------------------------------------------------------

    \38\ See table 2-6 ``New Hampshire Visibility Impairing EGU and 
ICI Point Sources'' in the NH Regional Haze SIP--Final May 2022.
---------------------------------------------------------------------------

    The second MANE-VU contribution analysis used a meteorologically 
weighted Q/d calculation to assess states' contributions to visibility 
impairment at MANE-VU Class I areas.\39\ This analysis focused 
predominantly on SO2 emissions and used cumulative 
SO2 emissions from a source and a state for the variable 
``Q,'' and the distance of the source or state to the IMPROVE monitor 
receptor at a Class I area as ``d.'' 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. Although MANE-VU did not 
originally estimate nitrate impacts, the MANE-VU Q/d analysis was 
subsequently extended to

[[Page 80666]]

account for nitrate contributions from NOX emissions and to 
approximate the nitrate impacts from area and mobile sources. MANE-VU 
therefore developed a ratio of nitrate to sulfate impacts based on the 
previously described CALPUFF modeling and applied those to the sulfate 
Q/d results in order to derive nitrate contribution estimates. Several 
states did not have CALPUFF nitrate to sulfate ratio results, however, 
because there were no point sources modeled with CALPUFF.
---------------------------------------------------------------------------

    \39\ See appendix D, ``Contribution Assessment 2006--Final.''
---------------------------------------------------------------------------

    In order to develop a final set of contribution estimates, MANE-VU 
weighted the results from both the Q/d and CALPUFF analyses. 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). If a state's contribution to 
sulfate and nitrate concentrations at a particular Class I area was 2 
percent or greater, MANE-VU regarded that state as contributing to 
visibility impairment in that area. According to MANE-VU's analyses, 
sources in New Hampshire have been found to contribute to visibility 
impairment at its own Class I areas, Acadia National Park and Moosehorn 
Wilderness Area in Maine, and, by extension, Roosevelt-Campobello 
International Park in New Brunswick.
    As explained above, the EPA concluded in the 1999 RHR that ``all 
[s]tates contain sources whose emissions are reasonably anticipated to 
contribute to regional haze in a Class I area,'' 64 FR at 35721, 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.
    First, as an aside, the screening analyses on which MANE-VU relied 
are useful for certain purposes. MANE-VU used information from its 
technical analysis to rank the largest contributing states to sulfate 
and nitrate impairment in seven Class I areas in the MANE-VU region and 
three additional, nearby Class I areas.\40\ 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). Additionally, large individual source impacts were used to 
target MANE-VU control analysis ``Asks'' \41\ of states and sources 
both within and upwind of MANE-VU.\42\ The EPA finds the nature of the 
analyses generally appropriate to support decisions on states with 
which to consult. However, we have cautioned that source selection 
methodologies that target the largest regional contributors to 
visibility impairment across multiple states may not be reasonable for 
a particular state if it results in few or no sources being selected 
for subsequent analysis. 2021 Clarifications Memo at 3.
---------------------------------------------------------------------------

    \40\ The Class I areas analyzed were Acadia National Park in 
Maine, Brigantine Wilderness in New Jersey, Great Gulf Wilderness 
and Presidential Range--Dry River Wilderness in New Hampshire, Lye 
Brook Wilderness in Vermont, Moosehorn Wilderness in Maine, 
Roosevelt-Campobello International Park in New Brunswick, Shenandoah 
National Park in Virginia, James River Face Wilderness in Virginia, 
and Dolly Sods/Otter Creek Wildernesses in West Virginia.
    \41\ As explained more fully in section IV.E.a, MANE-VU refers 
to each of the components of its overall strategy as an ``Ask ``of 
its member states.
    \42\ The MANE-VU consultation report (Appendix G) 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.''
---------------------------------------------------------------------------

    With regard to the analysis and determinations regarding New 
Hampshire's contribution to visibility impairment at out-of-state Class 
I areas, the MANE-VU technical work focuses on the magnitude of 
visibility impacts from certain New Hampshire emissions on its Class I 
area and other 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, Q/d analyses with a 
relatively simplistic accounting for wind trajectories and CALPUFF 
applied to a very limited set of EGUs and major industrial sources of 
SO2 and NOx are not scientifically rigorous tools capable of 
evaluating contribution to visibility impairment from all emissions in 
a state. The EPA does agree that the contribution to visibility 
impairment from New Hampshire's emissions at nearby out-of-state Class 
I areas is smaller than that from numerous other MANE-VU states.\43\ 
And while some MANE-VU states noted that the contributions from several 
states outside the MANE-VU region are significantly larger than its 
own, we again clarify that each state is obligated under the CAA and 
RHR to address regional haze visibility impairment resulting from 
emissions from within the state, irrespective of whether another 
state's contribution is greater. See 2021 Clarifications Memo at 3. 
Additionally, we note that the 2 percent or greater sulfate-plus-
nitrate threshold used to determine whether New Hampshire emissions 
contribute to visibility impairment at a particular Class I area may be 
higher than what EPA believes is an ``extremely low triggering 
threshold'' intended by the statute and regulations. In sum, based on 
the information provided, it is clear that emissions from New Hampshire 
contribute to visibility impairment in the Class I areas in Maine, New 
Brunswick, and New Hampshire and have relatively small contributions to 
the other nearby Class I areas. EPA generally agrees with this 
conclusion. However, due to the low triggering threshold implied by the 
Rule and the lack of rigorous modeling analyses, we do not necessarily 
agree with the level of the State's 2% contribution threshold as a 
general matter.
---------------------------------------------------------------------------

    \43\ Because MANE-VU did not include all New Hampshire's 
emissions or contributions to visibility impairment in its analysis, 
we cannot definitively state that New Hampshire's contribution to 
visibility impairment is not the most significant. However, that is 
very likely the case.
---------------------------------------------------------------------------

    Regardless, we note that New Hampshire did determine that sources 
and emissions within the state contribute to visibility impairment at 
both in-state wildernesses and three out-of-state Class I areas. 
Furthermore, the state 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 seven 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.\44\ New Hampshire'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. New 
Hampshire worked with MANE-VU to determine potential reasonable 
measures that could be implemented by 2028, considering the cost of 
compliance, the time necessary for

[[Page 80667]]

compliance, the energy and non-air quality environmental impacts, and 
the remaining useful life of any potentially affected sources. As 
discussed in further detail below, the EPA is proposing to find that 
New Hampshire 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. Thus, although we have concerns regarding some 
aspects of MANE-VU's technical analyses supporting states' contribution 
determinations as a general matter, we propose to find that New 
Hampshire has nevertheless satisfied the applicable requirements for 
making reasonable progress towards natural visibility conditions in 
Class I areas that may be affected be emissions from the state.
---------------------------------------------------------------------------

    \44\ See appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

D. Calculations of Baseline, Current, and Natural Visibility 
Conditions; Progress to Date; and the Uniform Rate of Progress

    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 conditions and natural 
visibility conditions, and the URP. This section also provides the 
option for states to propose adjustments to the URP line for a Class I 
area to account for visibility impacts from anthropogenic sources 
outside the United States and/or the impacts from wildland prescribed 
fires that were conducted for certain, specified objectives. 40 CFR 
51.308(f)(1)(vi)(B).
    The Great Gulf and Presidential Range--Dry River Wilderness areas 
have 2000-2004 baseline visibility conditions of 7.65 deciviews on the 
20% clearest days and 21.88 deciviews on the 20% most impaired 
days.\45\ New Hampshire calculated an estimated natural background 
visibility of 3.73 deciviews on the 20% clearest days and 9.78 
deciviews on the 20% most impaired days for the Great Gulf and 
Presidential Range--Dry River Wilderness areas.\46\ The current 
visibility conditions, which are based on 2015-2019 monitoring data, 
were 4.69 deciviews on the clearest days and 12.33 deciviews on the 
most impaired days,\47\ which represents an improvement from the 
baseline period of 2.96 deciviews on the 20% clearest days and 9.55 
deciviews on the 20% most impaired days.\48\ In addition, current 
visibility conditions are 0.96 and 2.55 deciviews greater than natural 
conditions on the respective sets of days.\49\ New Hampshire calculated 
an annual URP of 0.202 deciviews needed to reach natural visibility on 
the 20% most impaired days.\50\ New Hampshire noted that, at 12.33 
deciviews, current visibility conditions on the most impaired days in 
the Great Gulf/Presidential-Dry River Wilderness Area are already below 
the URP glidepath for both 2018--the end of the first SIP planning 
period--and 2028--the end of the second SIP planning period.\51\ New 
Hampshire has not proposed any adjustments to the URP to account for 
impacts from anthropogenic sources outside the United States or from 
wildland prescribed fires. EPA is proposing to find that New Hampshire 
has submitted a regional haze plan that meets the requirements of 40 
CFR 51.308(f)(1) related to the calculations of baseline, current, and 
natural visibility conditions; progress to date; and the uniform rate 
of progress for the second implementation period.
---------------------------------------------------------------------------

    \45\ See ``Table 4-1: Baseline Visibility for the 20% Clearest 
and 20% Worst Days for the Baseline Period in New Hampshire Class I 
Areas'' in the NH Regional Haze SIP submission--Final (May 2022).
    \46\ See ``Table 4-3: Comparison of Natural, Baseline, and 
Current Visibility for the 20% Clearest and 20% Most Impaired Days 
in New Hampshire Class I Areas'' in the NH Regional Haze SIP 
submission--Final (May 2022).
    \47\ See ``Table 4-2: Current Visibility for the 20% Clearest 
and 20% Most Impaired Days during 2015-2019 in New Hampshire Class I 
Areas'' in the NH Regional Haze SIP submission--Final (May 2022).
    \48\ NH Regional Haze SIP submission--Final, at 39 (May 2022).
    \49\ See ``Table 4-4: Current Visibility (2015-2019) vs. Natural 
Visibility Conditions (dv)'' in the NH Regional Haze SIP 
submission--Final (May 2022).
    \50\ See ``Table 4-6: Baseline, Current and Reasonable Progress 
Goal Haze Index Levels for New Hampshire's Class I Areas'' in the NH 
Regional Haze SIP submission--Final (May 2022).
    \51\ NH Regional Haze SIP submission--Final, at 40-41 (May 
2022).
---------------------------------------------------------------------------

E. Long-Term Strategy for Regional Haze

a. New Hampshire's Response to the Six MANE-VU Asks
    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 section 169A(b)(2)(B). As explained in the Background section 
of this notice, reasonable progress is achieved when all states 
contributing to visibility impairment in a Class I area are 
implementing the measures determined--through application of the four 
statutory factors to sources of visibility impairing pollutants--to be 
necessary to make reasonable progress. 40 CFR 51.308(f)(2)(i). Each 
state's long-term strategy must include the enforceable emission 
limitations, compliance schedules, and other measures that are 
necessary to make reasonable progress. 40 CFR 51.308(f)(2). All new 
(i.e., additional) measures that are the outcome of four-factor 
analyses are necessary to make reasonable progress and must be in the 
long-term strategy. If the outcome of a four-factor analysis and other 
measures necessary to make reasonable progress is that no new measures 
are reasonable for a source, that source's existing measures are 
necessary to make reasonable progress, unless the state can demonstrate 
that the source will continue to implement those measures and will not 
increase its emission rate. Existing measures that are necessary to 
make reasonable progress must also be in the long-term strategy. In 
developing its long-term strategies, a state must also consider the 
five additional factors in Sec.  51.308(f)(2)(iv). As part of its 
reasonable progress determinations, 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 emission reduction measures for 
inclusion in the long-term strategy. 40 CFR 51.308(f)(2)(i).
    In this section of the NPRM, EPA summarizes how New Hampshire 
addresses the requirements of Sec.  51.308(f)(2)(i), including a 
discussion of the six Asks developed by MANE-VU and how New Hampshire 
addressed each. In section IV.E.b of the NPRM, EPA evaluates New 
Hampshire's compliance with the requirements of Sec.  51.308(f)(2)(i).
    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 Sec.  51.308(f). Where an RPO has performed source 
selection and/or four-factor analyses (or considered the five 
additional factors in Sec.  51.308(f)(2)(iv)) for its member states, 
those states may rely on the RPO's analyses for the purpose of 
satisfying the requirements of Sec.  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. 40 CFR 
51.308(f)(2)(iii). States may also satisfy the requirement of Sec.  
51.308(f)(2)(ii) to engage in interstate consultation with other states 
that have emissions that are reasonably

[[Page 80668]]

anticipated to contribute to visibility impairment in a given Class I 
area under the auspices of intra- and inter-RPO engagement.
    New Hampshire 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 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.\52\ 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.'' \53\ 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.'' \54\
---------------------------------------------------------------------------

    \52\ See appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
    \53\ Id.
    \54\ 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 New Hampshire'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) \55\ 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 as SO2 emissions have 
decreased. The technical analyses used by New Hampshire are included in 
their submission and are as follows:
---------------------------------------------------------------------------

    \55\ The period of 2012-2016 was the most recent period for 
which data were available at the time of analysis. NH also included 
2015-2019 data, discussed above in part D of this section.
---------------------------------------------------------------------------

     2016 Updates to the Assessment of Reasonable Progress for 
Regional Haze in MANE-VU Class I Areas (Appendix L NH);
     Impact of Wintertime SCR/SNCR Optimization on Visibility 
Impairing Nitrate Precursor Emissions. November 2017. (Appendix Q NH);
     High Electric Demand Days and Visibility Impairment in 
MANE-VU. December 2017. (Appendix R NH);
     Benefits of Combined Heat and Power Systems for Reducing 
Pollutant Emissions in MANE-VU States. March 2016. (Appendix S NH);
     2016 MANE-VU Source Contribution Modeling Report--CALPUFF 
Modeling of Large Electrical Generating Units and Industrial Sources 
April 4, 2017 (Appendix C NH);
     Contribution Assessment Preliminary Inventory Analysis. 
October 10, 2016. (Appendix D NH);
     Four-Factor Data Collection Memo. March 2017. (Appendix K 
NH);
     Status of the Top 167 Stacks from the 2008 MANE-VU Ask. 
July 2016. (Appendix M NH).
    To support development of the Asks, MANE-VU gathered information on 
each of the four statutory factors for six source sectors it 
determined, based on an examination of annual emission inventories, 
``had emissions [of SO2 and/or NOX] 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.\56\ MANE-VU 
also collected data on individual sources within the EGU, ICI boiler, 
and cement kiln sectors.\57\ 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.\58\ Source-specific data 
included SO2 emissions \59\ and existing controls \60\ for 
certain existing EGUs, ICI boilers, and cement kilns. MANE-VU 
considered this information on the four factors as well as the analyses 
developed by the RPO's Technical Support Committee when it determined 
specific emission reduction measures that were found to be reasonable 
for certain sources within two of the sectors it had examined--EGUs and 
ICI boilers. The Asks were based on this analysis and looked to 
optimize the use of existing controls, have states conduct further 
analysis on EGU or ICI boilers with considerable visibility impacts, 
implement low sulfur fuel standards, or lock-in lower emission rates.
---------------------------------------------------------------------------

    \56\ See appendix K ``MANE-VU Four Factor Data Collection Memo 
at 1, March 30, 2017.''
    \57\ See appendix L ``2016 Updates to the Assessment of 
Reasonable Progress for Regional Haze in MANE-VU Class I Areas, Jan. 
31, 2016.''
    \58\ Id.
    \59\ See appendix K ``Four Factor Data Collection Memo.''
    \60\ See appendix M ``Status of the Top 167 Stacks from the 2008 
MANE-VU Ask. July 2016.''
---------------------------------------------------------------------------

    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.\61\ Twelve EGUs at seven 
stationary sources in New Hampshire were identified as meeting the 
criteria of Ask 1. These sources include Burgess BioPower (EU01), 
Essential Power Newington (EU01 and EU02), Granite Ridge Energy (EU01 
and EU02), Stored Solar Tamworth (EU01), GSP Merrimack Station (MK1 and 
MK2), GSP Schiller Station (SR4, SR5, and SR6), and GSP Newington 
Station (NT1). Additionally, the National Park Service identified 
Wheelabrator Concord as a facility of interest. NHDES determined that 
no further limitations as a result of MANE-VU Ask 1 were required of 
these sources.
---------------------------------------------------------------------------

    \61\ See appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

    New Hampshire explained that Burgess BioPower's operation was 
subject to Nonattainment New Source Review (NNSR) for NOX at 
the time of the facility's initial permitting; hence, the 
NOX limit represents the Lowest Available Emission Rate 
(LAER). This limit is incorporated into Title V Operating Permit TV-
0065, issued on December 24, 2020, which limits NOX

[[Page 80669]]

emissions from the biomass boiler to 0.060 lbs/MMBtu on a 30-day 
rolling average, based on the use of Selective Catalytic Reduction 
(SCR) technology and SO2 emissions to 0.012 lbs/MMBtu.
    Essential Power Newington was subject to NNSR for NOX at 
the time of initial permitting in July 2010; these NOX 
limits were established as LAER-based limits. The Newington units use 
dry low NOX (DLN) combustion combined with SCR (as well as 
water injection during limited firing on ultra-low sulfur fuel oil). 
The facility is required by permit to use inherently low sulfur fuels 
(natural gas and ultra-low sulfur fuel oil). The units at this facility 
were subject to Prevention of Significant Deterioration (PSD) review 
for SO2 at the time of their initial permitting; these 
SO2 limits (0.0071 lbs/MMBtu for natural gas, and 0.0015 
lbs/MMBtu for No. 2 fuel oil) were established as Best Available 
Control Technology (BACT) limits. These limits are incorporated into 
Title V Operating Permit TV-0058, which limits NOX and 
SO2 emissions on a year-round basis.
    The units at Granite Ridge Energy were subject to NNSR for 
NOX at the time of their initial permitting; these limits 
were established as LAER-based limits. The facility uses inherently low 
sulfur fuel (natural gas). The units at this facility were subject to 
PSD review for SO2 at the time of their initial permitting; 
this limit (0.0023 lbs/MMBtu) was established as a BACT-based limit. 
These limits are included in Title V Operating Permit TV-0056, which 
limits NOX and SO2 emissions on a year-round 
basis.
    Stored Solar Tamworth's operation is subject to an emission limit 
that was established when the facility was initially permitted under 
the PSD permit program in 1987. This control limits NOX 
emissions to 0.265 lbs/MMBtu over any consecutive 24-hour period. In 
2008, this facility installed overfire air (OFA) and flue gas 
recirculation (FGR) technologies, as well as a Selective Noncatalytic 
Reduction (SNCR) system and a SCR system. These limits are included in 
the facility's Title V Operating Permit TV-0018. Stored Solar Tamworth 
has voluntarily chosen to maintain NOX emissions at or below 
0.075 lb/MMBtu, on a quarterly average for the purpose of generating 
renewable energy certificates.
    In response to the MANE-VU ``Ask,'' Stored Solar Tamworth agreed to 
take lower year-round, enforceable NOX emission limitations. 
NHDES revised New Hampshire's Code of Administrative Rules Env-A 2300, 
``Mitigation of Regional Haze'' to include these limits and submitted 
the rule to EPA as part of this SIP revision. This rule will lower the 
NOX emissions limitations to a 30-day rolling average of 
0.075 lb/MMBtu or a 24-hour calendar day average of 0.085 lb/MMBtu.
    GSP Merrimack Station's operation is covered by Title V Operating 
Permit TV-0055 which limits NOX and SO2 
emissions. On May 3, 2018, NHDES requested information from GSP 
regarding NOX RACT and Regional Haze Rule requirements 
associated with the MANE-VU ``Ask.'' This request for information was 
focused on the most effective use of existing control technologies for 
MK1 and MK2. In addition, GSP completed an analysis of additional 
controls for NOX and SO2 for MK1 and MK2. After 
review, NHDES concluded the analysis validates the continued use of 
current enforceable measures for both SO2 and 
NOX. In response to the MANE-VU Ask, NHDES amended New 
Hampshire's Code of Administrative Rules Env-A 2300, ``Mitigation of 
Regional Haze'' to reference new NOX RACT limits for MK1, 
which New Hampshire has made more stringent, changing from 1.22 lb/
MMBtu (rolling 7-calendar day average), or 18.1 tons per calendar day 
(when MK2 is not in full operation), or 29.1 tons per calendar day 
(when combined with MK2) to 0.22 lb/MMBtu (24-hour calendar day 
average) or 4.0 tons per day on any calendar day during which a startup 
or shutdown occurs.\62\ NHDES also revised Env-A 2300 to reference the 
new NOX RACT limits for MK2 from 15.4 tons per 24-hour 
calendar day, or 29.1 tons per calendar day (when combined with MK1) to 
0.22 lb/MMBtu (24-hour calendar day average) or 11.5 tons per day on 
any calendar day during which a startup or shutdown occurs. NHDES 
submitted the revised Env-A 2300 to EPA as part of New Hampshire's 
Regional Haze SIP revision for the second implementation period.\63\
---------------------------------------------------------------------------

    \62\ See Table 4-15 ``Reductions in Allowable NOX 
RACT Emission Limits for MK1 and MK2 Over Time'' of the NH RH SIP, 
Final 2022.
    \63\ Env-A 2300 incorporates by reference NOX limits 
in Env-A 1300, which NHDES revised in 2018 as part of its SIP 
submittal for the 2008 and 2015 8-hr ozone standards. EPA has 
proposed in a separate action to approve Env-A 1300 into NH's SIP. 
See 88 FR 43483 (July 10, 2023). On September 6, 2023, EPA issued a 
final notice approving portions of Env-A 1300 in the NH SIP with the 
exception of New Hampshire's NOX RACT limits applicable 
to coal-fired cyclone boilers. See 88 FR 60893 (September 6, 2023). 
EPA will issue a decision on New Hampshire's NOX RACT 
requirements for coal-fired cyclone boilers in a subsequent 
rulemaking.
---------------------------------------------------------------------------

    GSP Schiller Station's operation is covered by Title V Operating 
Permit TV-0053 and NOX RACT Orders RO-003 and ARD-06-001 
which limit NOX and SO2 emissions. NHDES 
requested additional information from GSP regarding both NOX 
RACT and Regional Haze Rule requirements associated with the MANE-VU 
``Ask.'' For SR4 and SR6, NHDES requested that GSP conduct a 
NOX RACT analysis for optimization of the SNCR including an 
evaluation of the technical and economic feasibility of operating the 
SNCR systems on a year-round basis to achieve various proposed 
NOX emission levels. Also, GSP was requested to evaluate the 
most effective use of the DSI systems on SR4 and SR6 for SO2 
emission reductions. For ``Ask 1'' regarding SR5, NHDES requested GSP 
evaluate the most effective use of the SNCR for NOX emission 
reductions and the limestone injection system for SO2 
emission reductions. GSP provided analyses to demonstrate that 
operation of low NOX burners (LNB) and OFA on SR4 and SR6 
were sufficient to achieve an emission limit of 0.25 lbs 
NOX/MMBtu and that year-round operation of the SNCR would 
not result in any additional emissions reductions. NHDES issued 
NOX RACT Order RO-003 on September 6, 2018, which 
established a NOX emission limit for SR4 and SR6 of 0.25 
lbs/MMBtu per 24-hour calendar day average that applies at all times, 
including periods of startup and shutdown on a year-round basis. New 
Hampshire submitted this NOX RACT Order as a single-source 
SIP revision in September 2018. It was approved by the EPA on September 
12, 2019 (84 FR 48068).
    SR4 and SR6 also comply with the most current and strict federal 
standards for acid gases, the HCl limit required under MATS, and the 1-
hr SO2 NAAQS. GSP Schiller Station implements the most 
effective use of the existing control technology, which is year-round 
operation of the DSI systems, targeting reduction of multiple acid 
gases. SR5 is a wood-fired boiler that is also permitted to fire coal 
but has only fired coal for collecting performance test data in 
November 2006 during commissioning of the boiler. GSP has not combusted 
coal in SR5 since that time. Based on compliance stack testing and 
emissions monitoring data, sorbent injection is not needed to comply 
with the SO2 emission limit while burning biomass. NHDES 
determined that the existing pollution control equipment (LNB, OFA, 
SNCR and DSI) installed on SR4, SR5 and SR6, the federally enforceable 
NOX RACT emission limits and the NOX and 
SO2 emission limitations required by TV-0053 on a year-round 
basis satisfy Ask 1.
    The GSP Newington Station's unit subject to ``Ask 1'' at this 
facility is an oil- and natural gas-fired EGU designated as NT1. NT1 is 
equipped

[[Page 80670]]

with an electrostatic precipitator (ESP) to control the emissions of 
particulate matter and LNB, OFA and water injection system to control 
NOX emissions. GSP operates the water injection system on 
NT1 as necessary to maintain compliance with the NOX 
emission limits. NT1 is subject to MATS as an existing EGU under the 
``limited-use liquid oil-fired EGU72'' subcategory. These controls are 
included in the Title V Operating Permit TV-0054. TV-0054 contains a 
requirement to conduct a NOX RACT analysis within six months 
of switching from the limited use MATS subcategory to continental 
liquid oil-fired EGU subcategory should they ever do so. NT1 does not 
have ``already installed'' SO2 controls and therefore Ask 1 
applies only to its NOX emissions. NHDES determined that the 
existing pollution control equipment (LNB, OFA and water injection 
system) installed on NT1 combined with the federally enforceable 
NOX emission limitations required by TV-0054 on a year-round 
basis satisfy Ask 1.
    Wheelabrator Concord's operation is covered by Title V Operating 
Permit TV-0032, which was issued January 24, 2019. The two identical 
mass burn waterwall boilers at Wheelabrator Concord are considered 
large municipal waste combustion (MWC) units under New Hampshire's Code 
of Administrative Rules Env-A 3300, ``Municipal Waste Combustion.'' The 
two MWC units at Wheelabrator Concord are also subject to New 
Hampshire's Code of Administrative Rules Env-A 1300, ``NOX 
RACT'' (approved September 6, 2023, 88 FR 60893). Therefore, NHDES 
determined that no further limitations from MANE-VU Ask 1 are required 
of this source.
    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. GSP Merrimack Station, in Bow, was identified as the only 
facility in NH with the potential for 3.0 Mm-1 or greater 
visibility impact at any MANE-VU Class I area.
    GSP Merrimack Station's operation is already covered by Title V 
Operating Permit TV-0055 which limits NOX and SO2 
emissions. MK1 and MK2 are cyclone-firing, wet-bottom utility boilers 
that burn bituminous coal and are each equipped with SCR for 
NOX control as well as ESPs for particulate matter control. 
In addition, because of state law RSA 125-O, Multiple Pollutant 
Reduction Program, MK1 and MK2 are equipped with a common FGD system 
which is designed to reduce mercury emissions but has the co-benefit of 
acid gas (SO2 and HCl) removal. New Hampshire asked GSP to 
perform four-factor analyses for both MK1 and MK2. As a result of this 
request, GSP considered various control measures for NOX and 
SO2, which, for NOX, included review of fuel 
switching, OFA, SNCR, reburn, and upgrades to the existing SCR and, for 
SO2, considered upgrades to the existing FGD, coal cleaning, 
dry FGD, FGD plus DSI and fuel switching. GSP further noted that both 
units already employ SCR for controlling NOX emissions and 
that the existing FGD system already achieves a 95% reduction in 
SO2 emissions. GSP concluded that both units are already 
effectively controlled and that no additional measures would result in 
any additional emissions reductions.\64\ NHDES closely reviewed GSP's 
analysis and agreed with the company's conclusion that it supports the 
continued use of current enforceable measures for both SO2 
and NOX, that no upgrade or replacement of the controls on 
MK1 and MK2 are necessary to make reasonable progress, and that a full 
four-factor analysis would not have identified any additional controls 
required for reasonable progress. New Hampshire therefore concluded 
that it satisfies Ask 2.
---------------------------------------------------------------------------

    \64\ See NH SIP submittal Appendix T.
---------------------------------------------------------------------------

    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 ppm), #4 residual oil (0.25-0.5% 
sulfur by weight), and #6 residual oil (0.3-0.5% sulfur by weight). New 
Hampshire amended state law RSA 125-C:10-d, Sulfur Limits of Certain 
Liquid Fuels. Beginning on July 1, 2018, fuel imported into New 
Hampshire was required to meet the following reduced sulfur limits--
0.0015% for No. 2 fuel oil, 0.25% for No. 4 fuel oil and 0.5% for Nos. 
5 or 6 fuel oil--and as of February 1, 2019, non-compliant fuels are 
not allowed to be distributed for sale within the State. This law will 
result in further reductions in SO2 emissions from 
industrial, area, and non-road sources beyond the 30% reduction seen in 
the 2008 vs. 2014 NEI data. The law was incorporated into New 
Hampshire's Code of Administrative Rules Env-A 1600, Fuel 
Specifications and was submitted to the EPA as a SIP revision on May 
17, 2019, which EPA approved on April 26, 2021 (86 FR 21942). New 
Hampshire 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 at 
emissions sources larger than 250 million British Thermal Units (MMBtu) 
per hour heat input that have switched to lower emitting fuels. New 
Hampshire submitted that there are no such facilities in the State and 
therefore concluded it is meeting Ask 4.
    Ask 5 requests that MANE-VU states ``control NOX 
emissions for peaking combustion turbines 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 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.\65\ The Ask requests states to strive for 
NOX emission standards of no greater than 25 ppm for natural 
gas and 42 ppm for fuel oil, or at a minimum, NOX emissions 
standards of no greater than 42 ppm for natural gas and 96 ppm at for 
fuel oil. The peaking combustion turbines located at New Hampshire 
stationary sources that were identified as meeting the criteria of 
``Ask #5'' are: GSP Lost Nation Station (LNCT1) GSP Merrimack Station 
(MKCT1 and MKCT2), GSP Schiller Station (SRCT), and GSP White Lake 
Station (WLCT1). GSP performed four-factor analyses for reasonable 
installation or upgrade to NOX emission controls at these 
units, which indicated no additional NOX controls that GSP 
could be employed on any of the combustion turbines that are both 
technically and economically feasible. All five GSP turbines are of the 
same era (1968-1970) and have similar NOX emissions and 
specifications. Additionally, GSP has pledged to continue employing 
good combustion practices to optimize their NOX emissions 
profile. New Hampshire reviewed and adopted the four-factor analyses 
and concluded it is meeting Ask 5.
---------------------------------------------------------------------------

    \65\ See appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

    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

[[Page 80671]]

cells, wind and solar. New Hampshire participates in RGGI,\66\ a 
Northeast and Mid-Atlantic 10-state initiative to reduce greenhouse gas 
emissions that contribute to global climate change. The initiative 
creates a market for emissions allowances through a regional cap-and-
trade program for greenhouse gas emissions from area power plants. As a 
co-benefit of this program, emissions of particle producing pollutants 
are also reduced. New Hampshire emissions allowances are sold at 
quarterly auctions and the proceeds fund the Greenhouse Gas Emission 
Reduction (GHGER) Fund. The GHGER Fund is administered by the Public 
Utilities Commission, which distributes the funds to programs across 
the state to support energy efficiency, conservation, and demand 
response programs.
---------------------------------------------------------------------------

    \66\ For more info: https://www.energy.nh.gov/renewable-energy/regional-greenhouse-gas-initiative.
---------------------------------------------------------------------------

    New Hampshire's also explained the State's Renewable Portfolio 
Standard (RPS) statute, RSA 362-F: ``Electric Renewable Portfolio 
Standard'', requires each electricity provider to meet customer load by 
purchasing or acquiring certificates representing generation from 
renewable energy based on total megawatt-hours supplied. The RPS 
requirement increases from 4% in 2008 to 25.2% in 2025 and thereafter, 
based on type of renewable energy. A portion of this renewable 
portfolio energy generation comes from non-emitting sources such as 
hydro, solar and wind. New Hampshire therefore concluded it is meeting 
Ask 6.
    In sum, New Hampshire identified several SIP approved mechanisms 
for controlling pollutants that impair visibility and that are 
necessary for reasonable progress--including its regulations limiting 
sulfur content in fuels, the updated RACT rules at Env-A 1300, and the 
more stringent NOX limits at Stored Solar Tamworth 
implemented through Env-A 2300--which EPA is proposing to add to New 
Hampshire's SIP in this action. In addition to these SIP approved 
measures, New Hampshire also identified other federally enforceable and 
permanent controls including BACT and LAER limits from NNSR and PSD 
permitting that are incorporated into the facilities' Title V operating 
permits that have led to additional visibility improvements.
b. The EPA's Evaluation of New Hampshire's Response to the Six MANE-VU 
Asks and Compliance With Sec.  51.308(f)(2)(i)
    The EPA is proposing to find that New Hampshire has satisfied the 
requirements of Sec.  51.308(f)(2)(i) related to evaluating sources and 
determining the emission reduction measures that are necessary to make 
reasonable progress by considering the four statutory factors. We are 
proposing to find that New Hampshire has satisfied the four-factor 
analysis requirement through its analysis and actions to address MANE-
VU Asks 1, 2 3, and 5.
    As explained above, New Hampshire relied on MANE-VU's technical 
analyses and framework (i.e., the Asks) to select sources and form the 
basis of its long-term strategy. 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.\67\ 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.'' \68\ EPA proposes to find that New 
Hampshire reasonably evaluated the two pollutants--SO2 and 
NOX--that currently drive visibility impairment within the 
MANE-VU region and that it adequately explained and supported its 
decision to focus on these two pollutants through its reliance on the 
MANE-VU technical analyses cited in its submission.
---------------------------------------------------------------------------

    \67\ See appendix H ``Contribution Assessment--Final.''
    \68\ See Appendix G ``Asks--Final.''
---------------------------------------------------------------------------

    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 statutory factors to sources in a control 
analysis. 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. While MANE-VU 
formulated the Asks to be ``reasonable emission reduction strategies'' 
to control emissions of visibility impairing pollutants,\69\ EPA 
believes that New Hampshire, in four of the Asks in particular, engaged 
with the requirement that states determine the emission reduction 
measures that are necessary to make reasonable progress through 
consideration of the four factors. As laid out in further detail below, 
the EPA is proposing to find that MANE-VU's four-factor analysis 
conducted to support the emission reduction measures in Ask 3 (ultra-
low sulfur fuel oil), in conjunction with New Hampshire's analysis and 
explanation of how it has complied with Asks 1 (ensure the most 
effective use of control technologies on a year-round basis at certain 
EGUs), 2 (perform four-factor analyses for sources with potential for 
>=3.0 Mm-\1\ impacts), and 5 (perform four-factor analyses 
for measures to control NOX emissions at certain peaking 
combustion turbines) satisfy the requirement of Sec.  51.308(f)(2)(i). 
The emission reduction measures that are necessary to make reasonable 
progress must be included in the long-term strategy, i.e., in New 
Hampshire's SIP. 40 CFR 51.308(f)(2).
---------------------------------------------------------------------------

    \69\ Id.
---------------------------------------------------------------------------

    As for Ask 1, New Hampshire included an analysis of twelve EGUs at 
seven stationary sources that were identified as meeting the criteria 
of the Ask (i.e., capacity >=25MW with already installed NOX 
and/or SO2 controls). New Hampshire, in response to an FLM 
request, also added two Wheelabrator Concord MWC units to this 
analysis. New Hampshire identified existing controls, updated RACT 
limits, and new limits implemented in Env-A 2300, Mitigation of 
Regional Haze. Technical analyses were also completed for two of the 
EGUs as discussed more below under Ask 2. New Hampshire asserted that 
it satisfies Ask 1 because its SIP-approved regulations include year-
round emission limits and because it already requires that controls be 
run year-round for both NOX and SO2 by setting 
emission limits in permits that reflect the emission levels when the 
controls are run. As discussed in the previous section, New Hampshire 
included a description of existing rules, permit limits, and updated 
regulations to meet the requirements of Ask 1. New Hampshire has also 
increased controls on RACT (which EPA has proposed to approve in a 
separate notice), and EPA proposes to find that New Hampshire

[[Page 80672]]

reasonably concluded that it has satisfied Ask 1.
    Ask 2 addresses the sources MANE-VU determined have the potential 
for larger than, or equal to, 3.0 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 the emission reduction measures necessary to 
make 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.'' \70\
---------------------------------------------------------------------------

    \70\ See Appendix E ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

    As an initial matter, EPA does not generally agree that 3.0 
Mm-\1\ visibility impact is a reasonable threshold for 
source selection. The RHR recognizes that, due to the nature of 
regional haze visibility impairment, numerous and sometimes relatively 
small sources may need to be selected and evaluated for control 
measures in order to make reasonable progress. See 2021 Clarifications 
Memo at 4. As explained in the 2021 Clarifications Memo, while states 
have discretion to choose any source selection threshold that is 
reasonable, ``[a] state that relies on a visibility (or proxy for 
visibility impact) threshold to select sources for four-factor analysis 
should set the threshold at a level that captures a meaningful portion 
of the state's total contribution to visibility impairment to Class I 
areas.'' 2021 Memo at 3. In this case, the 3.0 Mm-\1\ 
threshold identified only one unit at one source in New Hampshire (and 
only 22 across the entire MANE-VU region), indicating that it may be 
unreasonably high.
    At 3.3 Mm-\1\, Unit 2 at GSP Merrimack Station (MK2), in 
Bow, was identified as the only EGU in NH with the potential for 3.0 
Mm-\1\ or greater visibility impact at any MANE-VU Class I 
area. As noted above, GSP Merrimack Station's operation is covered by 
Title V Operating Permit TV-0055 which limits NOX and 
SO2 emissions. MK1 and MK2 are each equipped with SCR for 
NOX control as well as ESPs for particulate matter control. 
In addition, because of state law NH RSA 125-O, Multiple Pollutant 
Reduction Program, MK1 and MK2 are equipped with a common FGD system 
which is designed to reduce mercury emissions but has the co-benefit of 
acid gas (SO2 and HCl) removal. While only Unit 2 was 
identified by MANE-VU as contributing a 3.0 Mm-\1\ or 
greater visibility impact at any MANE-VU Class I area, New Hampshire 
asked GSP to perform four-factor analyses for both Units 1 and 2. GSP 
responded that both units already employ SCR for controlling 
NOX emissions and that the existing FGD system already 
achieves a 95% reduction in SO2 emissions. Consequently, GSP 
concluded that both units are already effectively controlled and that 
any additional control measures would not result in any additional 
emissions reductions.\71\ Based on a showing of existing effective 
controls, New Hampshire concluded that the result of a four-factor 
analysis would likely be no new controls and that no upgrade or 
replacement of the existing pollution control equipment was required as 
a result of Ask 2.
---------------------------------------------------------------------------

    \71\ See NH SIP submittal Appendix T.
---------------------------------------------------------------------------

    The EPA proposes to find that New Hampshire reasonably determined 
it has satisfied Ask 2. As explained above, we do not generally agree 
that a 3.0 Mm-\1\ threshold for selecting sources for four-
factor analysis results in a set of sources the evaluation of which has 
the potential to meaningfully reduce the state's contribution to 
visibility impairment. MANE-VU's threshold identified only one source 
in New Hampshire for four-factor analysis. However, EPA notes that New 
Hampshire considered the four statutory factors in determining the 
emissions reduction measures necessary for some of its other top-
impacting EGUs as part of Ask 5,\72\ including Lost Nation and White 
Lake, which, according to New Hampshire's submission, have the 
potential for visibility impacts at the Presidential Range-Dry River 
Wilderness of 1.87 and 2.2 Mm-\1\, respectively.\73\ EPA is 
basing this proposed finding on the state's examination of its largest 
operating EGU sources, at the time of SIP submission, and on the 
emissions from and controls that apply to those sources, as well as on 
New Hampshire's existing SIP-approved NOX and SO2 
rules that effectively control emissions from the largest contributing 
stationary-source sectors.
---------------------------------------------------------------------------

    \72\ See NH SIP submittal Appendix T.
    \73\ See page 22 of the NH Regional Haze SIP submission--(May 
2022).
---------------------------------------------------------------------------

    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; specifically, for 
the control strategy of 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 the 
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.'' \74\ The analysis further noted the 
beneficial energy and non-air quality environmental impacts 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.\75\
---------------------------------------------------------------------------

    \74\ Id. see 8-7.
    \75\ Id. see 8-8.
---------------------------------------------------------------------------

    The EPA proposes to find that New Hampshire reasonably relied on 
MANE-VU's four-factor analysis for a low-sulfur fuel oil regulation, 
which engaged with each of the statutory factors and explained how the 
information supported a conclusion that a 15 ppm-sulfur fuel oil 
standard for fuel oils is

[[Page 80673]]

reasonable. New Hampshire's SIP-approved ultra-low sulfur fuel oil rule 
\76\ is consistent with Ask 3's sulfur content standards for the three 
types of fuel oils (distillate oil, #4 residual oil, #6 residual oil). 
EPA therefore proposes to find that New Hampshire reasonably determined 
that it has satisfied Ask 3.
---------------------------------------------------------------------------

    \76\ Env-A 1600, Fuel Specifications was approved by EPA as a 
SIP revision on April 26, 2021 [86 FR 21942].
---------------------------------------------------------------------------

    New Hampshire concluded that no additional updates were needed to 
meet Ask 4, which requests that MANE-VU states pursue updating permits, 
enforceable agreements, and/or rules to lock-in lower emission rates 
for sources larger than 250 MMBtu per hour that have switched to lower 
emitting fuels. EPA agrees that New Hampshire does not contain any 
sources encompassed by this Ask, except that Schiller Station Unit 5 
technically maintains the ability to operate by burning coal. We note, 
however, that Schiller Station Unit 5 has not burned coal other than 
for stack testing at installation, and it is reasonable to conclude, 
for a number of reasons--including historic operation, financial 
viability, fuel availability, and the overall direction of the fuels 
market--that it is unlikely that this source will ever burn coal again. 
GSP reportedly laid off union staff at Schiller Station and locked the 
gates to the facility in June of 2020.77 78 All three of the 
steam units at Schiller have reported zero operating hours and zero 
emissions since 2020.\79\ Additionally, Schiller does not have any 
current capacity supply obligation for its steam units (which includes 
Unit 5) in the Forward Capacity Market and did not offer a bid for them 
in ISO New England's latest Forward Capacity Auction (FCA 17), which 
secures future power supply obligations through May 2027, making it 
unlikely that these units will ever operate in any capacity again.\80\
---------------------------------------------------------------------------

    \77\ N.H. Coal Plant Will Run Through At Least 2025 After Latest 
Grid Auction, NH Pub. Radio (Mar. 1, 2021), available at https://www.nhpr.org/climate-change/2021-03-01/n-h-coal-plant-will-run-through-at-least-2025-after-latest-grid-auction; Union says Schiller 
coal-fired power plant is shut for good, Granite Geek (Jan. 12, 
2021), available at https://granitegeek.concordmonitor.com/2021/01/12/union-says-schiller-coal-fired-power-plant-is-shut-for-good/.
    \78\ See https://www.ibew1837.org/content/schiller-station-closing-end-era, or see PDF version of this article in the docket.
    \79\ See EPA's Clean Air Markets Program Data (CAMPD) at https://campd.epa.gov/data.
    \80\ See https://www.iso-ne.com/markets-operations/markets/forward-capacity-market/ to download ISO New England forward 
capacity auction results. This spreadsheet has also been added to 
the docket for this notice.
---------------------------------------------------------------------------

    Ask 5 addresses NOX emissions from peaking combustion 
turbines that have the potential to operate on high electric demand 
days. New Hampshire identified five combustion turbines in the State as 
meeting the criteria of this Ask: GSP Lost Nation Station (LNCT1), GSP 
Merrimack Station (MKCT1 and MKCT2), GSP Schiller Station (SRCT), and 
GSP White Lake Station (WLCT1). The Ask requests states to strive for 
certain NOX emission standards for such sources or to 
perform four-factor analyses for reasonable installation or upgrade to 
emission controls. None of the five turbines New Hampshire identified 
are currently meeting the NOX emissions standards in the 
Ask, so New Hampshire requested four-factor analyses for each source. 
Each combustion turbine is owned by Granite Shore Power, was originally 
installed around the same time (1968-1970), has a similar unit rating 
(290 MMBtu/hr-319 MMBtu/hr), operates at an annual capacity factor 
below 1%, and has NOX emissions ranging from 0.7 lbs/MMBtu 
to 0.9 lbs/MMBtu. The total average yearly emissions for these sources 
from 2018-2022 were: GSP Lost Nation Station (LNCT1)--2.698 tons, GSP 
Merrimack Station (MKCT1)--2.596 tons, (MKCT2)--2.738 tons, GSP 
Schiller Station (SRCT)--2.582 tons, and GSP White Lake Station 
(WLCT1)--3.595 tons. Based on the four-factor analyses, New Hampshire 
concluded that no additional NOX controls are both 
technically and economically feasible for these sources EPA proposes to 
find that New Hampshire reasonably concluded that it has met the 
requirements of Ask 5.
    Finally, with regard to Ask 6, New Hampshire explains the clean 
energy requirements within the state including New Hampshire's 
Renewable Portfolio Standard (RPS) statute, NH RSA 362-F: Electric 
Renewable Portfolio Standard, and the State's participation in RGGI to 
reduce greenhouse gas emissions. The EPA is proposing to find that New 
Hampshire 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, New Hampshire identified several mechanisms for controlling 
pollutants that impair visibility--including its regulations limiting 
sulfur content in fuels (which are in New Hampshire's SIP), the 
previously discussed updated RACT rules at Env-A 1300 (which EPA has in 
a separate action recently proposed to approve into the SIP), and the 
more stringent NOX limits at Stored Solar Tamworth 
implemented through Env-A 2300 (which EPA is proposing to add to the 
SIP in this action). EPA proposes that New Hampshire has reasonably 
concluded that these measures are necessary to make reasonable progress 
for the second planning period. In addition to these SIP approved 
measures, New Hampshire also identified other federally enforceable and 
permanent controls including BACT and LAER limits from NNSR and PSD 
permitting, that are incorporated into the facilities' Title V 
operating permits.
    EPA is proposing to find--based on New Hampshire's participation in 
the MANE-VU planning process, how it has addressed the Asks, and the 
EPA's assessment of New Hampshire's emissions and point sources--that 
New Hampshire has complied with the requirements of Sec.  
51.308(f)(2)(i).
    EPA is proposing to find the state's approach reasonable for 
several reasons. New Hampshire reasonably evaluated and explained its 
decision to focus on SO2 and NOX to address 
visibility impairment within the MANE-VU region. And New Hampshire 
adequately supported that decision through reasonable reliance on the 
MANE-VU technical analyses cited in its submission. In addition, New 
Hampshire selected the sources with the greatest modeled impacts on 
visibility and also analyzed sources identified by the FLMs through the 
consultation process. New Hampshire's submittal also includes four-
factor analyses and demonstrates that the sources of SO2 and 
NOX within the state that would be expected to contribute to 
visibility impairment have small emissions of NOX and 
SO2, are subject to stringent emission control measures, or 
both. In addition, New Hampshire's SIP-approved sulfur in fuel rule 
sets stringent limits for sulfur content and SO2 emissions 
for fuels. The New Hampshire SIP submittal also includes Env-A 2300, 
which lowers NOX emission limits for Stored Solar Tamworth 
and incorporates by reference an updated Env-A 1300, which includes 
lower NOX limits for several sources including Merrimack 
Station and Wheelabrator Concord.
    EPA proposes to find that New Hampshire's SIP submittal satisfies 
the requirements that states determine the emission reduction measures 
that are 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.

[[Page 80674]]

c. Additional Long-Term Strategy Requirements
    The consultation requirements of Sec.  51.308(f)(2)(ii) provide 
that states must consult with other states that are reasonably 
anticipated to contribute to visibility impairment in a Class I area to 
develop coordinated emission management strategies containing the 
emission reductions necessary to make reasonable progress. Section 
51.308(f)(2)(ii)(A) and (B) respectively require states to include in 
their SIPs measures agreed to during state-to-state consultations or a 
regional planning process and to consider the emission reduction 
measures identified by other states as necessary for reasonable 
progress. Section 51.308(f)(2)(ii)(C) speaks to what happens if states 
cannot agree on what measures are necessary to make reasonable 
progress.
    New Hampshire participated in and provided documentation of the 
MANE-VU intra- and inter-RPO consultation processes, which included 
consulting with both MANE-VU and non-MANE-VU states about emissions 
reasonably anticipated to contribute to visibility impairment in New 
Hampshire's Class I areas and emissions from New Hampshire reasonably 
anticipated to contribute to visibility impairment in other Class I 
areas. The consultations addressed developing coordinated emission 
management strategies containing the emission reductions necessary to 
make reasonable progress at the Class I areas. New Hampshire addressed 
impacts to the MANE-VU Class I areas by providing information on the 
measures it has in place that satisfy each MANE-VU Ask.\81\ New 
Hampshire received comments from North Carolina, Virginia, and West 
Virginia on New Hampshire's Draft SIP. The comments generally disagree 
with MANE-VU's requests of non-MANE-VU states. The comments do not 
include any requests that New Hampshire consider additional measures to 
address visibility impairment in Class I areas in those respective 
States. MANE-VU documented these and other disagreements that occurred 
during consultation. For instance, MANE-VU noted in its Consultation 
Report that upwind states expressed concern regarding the analyses the 
RPO used for the selection of states for the consultation. MANE-VU 
agreed that these tools, as all models, have their limitations, but 
nonetheless deemed them appropriate. Additionally, there were several 
comments regarding the choice of the 2011 modeling base year. MANE-VU 
agreed that the choice of base year is critical to the outcome of the 
study. MANE-VU acknowledged that there were newer versions of the 
emission inventories and the need to use the best available inventory 
for each analysis. However, MANE-VU disagreed that the choice of these 
inventories was not appropriate for the analysis.
---------------------------------------------------------------------------

    \81\ See appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

    In sum, New Hampshire participated in the MANE-VU intra- and inter-
RPO consultation and included in its SIP submittal the measures 
identified and agreed to during those consultations, thereby satisfying 
Sec.  51.308(f)(2)(ii)(A) and (B). New Hampshire satisfied Sec.  
51.308(f)(2)(ii)(C) by participating in MANE-VU's consultation process, 
which documented the disagreements between the upwind states and MANE-
VU and explained MANE-VU's reasoning on each of the disputed issues. 
Based on the entirety of MANE-VU's intra- and inter-RPO consultation 
and both MANE-VU's and New Hampshire's responses to states' comments on 
the SIP submission \82\ and various technical analyses therein, we 
propose to determine that New Hampshire has satisfied the consultation 
requirements of Sec.  51.308(f)(2)(ii).
---------------------------------------------------------------------------

    \82\ See NH Submittal, Appendix W.
---------------------------------------------------------------------------

    The documentation requirement of Sec.  51.308(f)(2)(iii) provides 
that states may meet their obligations to document the technical bases 
on which they are relying to determine the emission reductions measures 
that are necessary to make reasonable progress through an RPO, as long 
as the process has been ``approved by all State participants.'' As 
explained above, New Hampshire chose to rely on MANE-VU's technical 
information, modeling, and analysis to support development of its long-
term strategy. The MANE-VU technical analyses on which New Hampshire 
relied are listed in the state's SIP submission and include source 
contribution assessments, information on each of the four factors and 
visibility modeling information for certain EGUs, and evaluations of 
emission reduction strategies for specific source categories. New 
Hampshire also provided information to further demonstrate the 
technical bases and emission information on which it relied on to 
determine the emission reductions measures that are necessary to make 
reasonable progress. Based on the documentation provided by the state, 
we propose to find New Hampshire satisfies the requirements of Sec.  
51.308(f)(2)(iii).
    Section 51.308(f)(2)(iii) also requires that the emissions 
information considered to determine the measures that are necessary to 
make reasonable progress include information on emissions for the most 
recent year for which the state has submitted triennial emissions data 
to the EPA (or a more recent year), with a 12-month exemption period 
for newly submitted data. New Hampshire's SIP submission included 2017 
NEI emission data for NOX, SO2, PM, VOCs and NH3 
and 2016-2019 Air Markets Program Data (AMPD) emissions for 
NOX and SO2. Based on New Hampshire's 
consideration and analysis of the emission data in their submittal, the 
EPA proposes to find that New Hampshire has satisfied the emissions 
information requirement in 51.308(f)(2)(iii).
    We also propose to find that New Hampshire reasonably considered 
the five additional factors in Sec.  51.308(f)(2)(iv) in developing its 
long-term strategy. Pursuant to Sec.  51.308(f)(2)(iv)(A), New 
Hampshire noted that existing and ongoing state and federal emission 
control programs that contribute to emission reductions through 2028 
would impact emissions of visibility impairing pollutants from point 
and nonpoint sources in the second implementation period. New Hampshire 
included in its SIP a list of control measures with their effective 
dates, pollutants addressed, and corresponding State regulations.\83\
---------------------------------------------------------------------------

    \83\ See Section 4.2.8 of the New Hampshire SIP.
---------------------------------------------------------------------------

    New Hampshire's consideration of measures to mitigate the impacts 
of construction activities as required by Sec.  51.308(f)(2)(iv)(B) 
includes a list of measures that New Hampshire has implemented to 
mitigate the impacts from such activities. New Hampshire's Code of 
Administrative Rules Env-A 1000, Prevention, Abatement, and Control of 
Open Source Air Pollution, requires the control of direct emissions of 
particulate matter (primarily crustal material) from mining, 
transportation, storage, use, and removal activities. These 
requirements apply to such sources as quarries, unpaved roads, cement 
plants, construction sites, rock-crushing operations, and general 
earth-moving activities. Controls may include wet suppression, 
covering, vacuuming, and other approved means. EPA originally approved 
the rule effective March 19, 2018 [83 FR 6972]. Additionally, New 
Hampshire's Code of Administrative Rules Env-A 2800, Sand and Gravel 
Sources: Non-Metallic Mineral Processing Plants; Cement and Concrete 
Sources, requires the control of

[[Page 80675]]

fugitive dust and standards for particulate matter emissions and 
visible emissions from sand and gravel sources, non-metallic mineral 
processing plants, and cement and concrete sources. EPA approved the 
rule effective December 7, 2016 [81 FR 78052].
    Pursuant to Sec.  51.308(f)(2)(iv)(C), New Hampshire acknowledged 
the most impactful of the State's sources are the fossil-fuel-fired 
EGUs. While recent developments in the oil and gas industry have forced 
rapid changes in the power production sector, and some generating units 
have experienced sharp reductions in utilization, no retirements or 
replacements of New Hampshire's EGUs have occurred or been announced 
since the regional haze SIP was first submitted in 2010. Although 
Schiller Station has been in an extended outage since June of 2020, no 
official word from the Facility's owner has been announced regarding a 
permanent shut down. As noted earlier, however, the facility reportedly 
laid off staff and locked the gates to the facility in June of 2020. 
Furthermore, as also previously noted, Schiller Station does not have a 
current capacity supply obligation for any coal unit and did not place 
a bid for any of these units in ISO New England's FCA 17, which secures 
power supply obligations through May of 2027.
    In considering smoke management as required in 40 CFR 
51.308(f)(2)(iv)(D), New Hampshire explained that it addresses smoke 
management through the New Hampshire Prescribed Fire Council. The U.S. 
Forest Service and NHDES are members of the Council and assisted in the 
development of burn standards.\84\ Federal Class I areas are not 
specifically identified as smoke sensitive features. New Hampshire's 
Class I areas are within the White Mountain National Forest; thus, the 
FLM for New Hampshire's two Class I areas (in this case, the U.S. 
Forest Service) would be informed of any planned burn in nearby lands. 
For any prescribed fire within this area, the burn plan would have to 
meet the FLM's own requirements for protection of Federal Class I 
areas, which are even more stringent than the New Hampshire Prescribed 
Fire Council's standards.
---------------------------------------------------------------------------

    \84\ NH Prescribed Fire Council, (March 2019). Planning for 
Prescribed Burning in New Hampshire--Minimum Recommended Standards 
for Planning & Implementing Prescribed Burns. Available at https://extension.unh.edu/resources/files/Resource001886_Rep2781.pdf.
---------------------------------------------------------------------------

    New Hampshire considered the anticipated net effect of projected 
changes in emissions as required by 51.308(f)(2)(iv)(E) by discussing 
the photochemical modeling for the 2018-2028 period it conducted in 
collaboration with MANE-VU. The two modeling cases run were a 2028 base 
case, which considered only on-the-books controls, and a 2028 control 
case that considered implementation of the MANE-VU Ask. New Hampshire 
presented the differences between the base and control cases on the 20% 
most impaired and 20% clearest days for the Great Gulf Wilderness Area 
\85\ and noted the success of measures implemented during the first 
planning period to reduce impairment.
---------------------------------------------------------------------------

    \85\ See Table 4-19 of the NH Regional Haze SIP.
---------------------------------------------------------------------------

    Because New Hampshire has reasonably considered each of the five 
additional factors, the EPA proposes to find that New Hampshire has 
satisfied the requirements of 40 CFR 51.308(f)(2)(iv).

F. Reasonable Progress Goals

    Section 51.308(f)(3) contains the requirements pertaining to RPGs 
for each Class I area. Because New Hampshire is host to a Class I area, 
it is subject to both Sec.  51.308(f)(3)(i) and, potentially, to (ii). 
Section 51.308(f)(3)(i) requires a state in which a Class I area is 
located to establish RPGs--one each for the most impaired and clearest 
days--reflecting the visibility conditions that will be achieved at the 
end of the implementation period as a result of the emission 
limitations, compliance schedules and other measures required under 
paragraph (f)(2) to be in states' long-term strategies, as well as 
implementation of other CAA requirements. The long-term strategies as 
reflected by the RPGs must provide for an improvement in visibility on 
the most impaired days relative to the baseline period and ensure no 
degradation on the clearest days relative to the baseline period. 
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 Sec.  51.308(f)(3)(ii)(A), if the 
state in which a mandatory Class I area is located establishes an RPG 
for the most impaired days that provides for a slower rate of 
visibility improvement than the URP, the state must demonstrate that 
there are no additional emission reduction measures for anthropogenic 
sources or groups of sources in the state that would be reasonable to 
include in its long-term strategy. Section 51.308(f)(3)(ii)(B) requires 
that if a state contains sources that are reasonably anticipated to 
contribute to visibility impairment in a Class I area in another state, 
and the RPG for the most impaired days in that Class I area is above 
the URP, the upwind state must provide the same demonstration.
    Table 4-19 of New Hampshire's SIP submittal summarizes baseline 
visibility conditions (i.e., visibility conditions during the baseline 
period of 2000-2004) for the most impaired and clearest days and the 
2028 RPG for the most impaired days for New Hampshire's Class I areas, 
as well as information on natural visibility conditions, the rate of 
progress described by the URP in 2028, and the modeled 2028 base case 
(representing visibility conditions in 2028 with existing controls). 
Baseline visibility conditions at New Hampshire's Class I areas were 
7.65 and 21.88 deciviews for the clearest and most impaired days, 
respectively. By comparison, New Hampshire has established 2028 RPGs 
for the clearest and most impaired days of 5.11 and 12.13 
deciviews.86 87
---------------------------------------------------------------------------

    \86\ See Table 4-6 of the NH Regional Haze SIP. These values 
were modeled not including the MANE-VU Asks. The values for the 
clearest and most impaired days including the Asks were 5.06 and 
12.00 deciviews, respectively.
    \87\ See also NH Submittal, Appendix W at 7 (indicating that the 
RPG for New Hampshire's Class I Areas is 12.13 deciviews).
---------------------------------------------------------------------------

    New Hampshire's 2028 most impaired base case of 12.13 deciviews 
reflects the visibility conditions that are projected to be achieved 
based on states' existing measures. As such, EPA considers the 2028 
modeled base case value of 12.13 deciviews to be the appropriate 
estimate of the RPG for the 20% most impaired visibility days (as 
opposed to the 12.00 deciviews value that includes measures from the 
MANE-VU Asks). EPA expects that the observed deciview value in 2028 
will actually be equal to or lower than the 12.13 deciview estimate due 
to numerous coal-fired utility boilers in upwind states having recently 
retired or being expected to retire under enforceable commitments 
before 2028. Even the conservative estimate of 12.13 deciviews on the 
most impaired days in 2028 constitutes improvement over the baseline 
visibility conditions of 21.88 deciviews. Therefore, the long-term 
strategy and the reasonable progress goals 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. 40 CFR 51.308(f)(3)(i).
    As noted in the RHR at 40 CFR 51.308(f)(3)(iii), the reasonable 
progress goals are not directly enforceable, but will be considered by 
the Administrator in evaluating the adequacy of the measures in the 
implementation plan in providing for reasonable progress

[[Page 80676]]

towards achieving natural visibility conditions at that area. The 2028 
RPG for the most impaired days of 12.13 deciviews fulfills the 
regulatory purpose of the RPGs because visibility conditions at New 
Hampshire's Class I areas have improved since the baseline period. EPA 
is therefore proposing to find that New Hampshire's RPGs satisfy the 
applicable requirements and provide for reasonable progress towards 
achieving natural conditions.
    Table 4-19 of New Hampshire's submission shows the URP glidepath 
value for New Hampshire's Class I areas in 2028 as 17.04 deciviews. New 
Hampshire's RPG is well below the glidepath value, thus the 
demonstration requirement under Sec.  51.308(f)(3)(ii)(A) is not 
triggered. Under Sec.  51.308(f)(3)(ii)(B), a state that contains 
sources that are reasonably anticipated to contribute to visibility 
impairment in a Class I area in another state for which a demonstration 
by the other state is required under 51.308(f)(3)(ii)(B) must 
demonstrate that there are no additional emission reduction measures 
that would be reasonable to include in its long-term strategy. New 
Hampshire's SIP revision included the modeled MANE-VU 2028 visibility 
projections at nearby Class I areas.\88\ While these projections may 
not represent the final RPGs for these Class I areas, all of the base 
case 2028 projections for the most impaired days at these areas 
(Acadia, Brigantine, Campobello, Lye Brook, Moosehorn, Dolly Sods, 
James River Face, Otter Creek, and Shenandoah) are well below the 
respective 2028 points on the URPs. Therefore, we propose it is 
reasonable to assume that the demonstration requirement under Sec.  
51.308(f)(3)(ii)(B) as it pertains to these areas will not be triggered 
for New Hampshire.
---------------------------------------------------------------------------

    \88\ See Appendix B ``Mid-Atlantic/Northeast U.S. Visibility 
Data 2004-2019 (2nd RH SIP Metrics.''
---------------------------------------------------------------------------

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 reporting, recordkeeping and other 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. 
Compliance with this requirement may be met through participation in 
the Interagency Monitoring of Protected Visual Environments (IMPROVE) 
network.
    The IMPROVE monitor for the Great Gulf Wilderness (GRGU1) is 
located at Camp Dodge, in the mid-northern area of Greens Grant in the 
White Mountain National Forest. The monitor site lies just east and 
south of where Route 16 crosses the Greens Grant/Martins Location 
boundary, south of Gorham, New Hampshire, at elevation 454 meters, 
latitude 44.31[deg], and longitude of -71.22[deg]. This monitor, which 
also represents the Presidential Range--Dry River Wilderness, is 
operated and maintained by the U.S. Forest Service.
    Section 51.308(f)(6)(i) requires SIPs to provide for the 
establishment of any additional monitoring sites or equipment needed to 
assess whether reasonable progress goals to address regional haze for 
all mandatory Class I Federal areas within the state are being 
achieved. New Hampshire has not received any recommendations or advice 
from EPA or affected FLM that additional monitoring is required 
pursuant to 40 CFR 51.308(f)(4). Therefore, New Hampshire has no 
current plans to alter the current strategy as long as this monitoring 
continues to be federally supported.
    Section 51.308(f)(6)(ii) requires SIPs to provide for procedures by 
which monitoring data and other information are used in determining the 
contribution of emissions from within the state to regional haze 
visibility impairment at mandatory Class I Federal areas both within 
and outside the state. New Hampshire relied on the MANE-VU contribution 
assessment analysis.\89\ The analysis included Eulerian (grid-based) 
source models, Lagrangian (air parcel-based) source dispersion models, 
as well as a variety of data analysis techniques that include source 
apportionment models, back trajectory calculations, and the use of 
monitoring and inventory data.
---------------------------------------------------------------------------

    \89\ See Appendix G for the contribution assessments.
---------------------------------------------------------------------------

    Section 51.308(f)(6)(iii) does not apply to New Hampshire, as it 
has a Class I area.
    Section 51.308(f)(6)(iv) requires the SIP to provide for the 
reporting of all visibility monitoring data to the Administrator at 
least annually for each Class I area in the state. As noted above, the 
Great Gulf Wilderness IMPROVE monitor is operated and maintained by the 
U.S. Forest Service. The monitoring strategy for New Hampshire relies 
upon the continued availability of the IMPROVE network. The IMPROVE 
monitor for the Great Gulf Wilderness (indicated as GRGU1 in the 
IMPROVE monitoring network database) is located at the base of Mt. 
Washington. New Hampshire supports the continued operation of the 
IMPROVE network through both state and Federal funding mechanisms.
    Section 51.308(f)(6)(v) requires SIPs to provide for a statewide 
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. New Hampshire provides for emissions 
inventories and estimates for future projected emissions by 
participating in the MANE-VU RPO and complying with EPA's Air Emissions 
Reporting Rule (AERR). In 40 CFR part 51, subpart A, the AERR requires 
states to submit updated emissions inventories for criteria pollutants 
to EPA's Emissions Inventory System (EIS) every three years. The 
emission inventory data are used to develop the NEI, which provides 
for, among other things, a triennial state-wide inventory of pollutants 
that are reasonably anticipated to cause or contribute to visibility 
impairment.
    Section 5 of New Hampshire's submission includes tables of 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.\90\ New Hamshire included NEI emissions inventories for 
the following years: 2002 (one of the regional haze program baseline 
years), 2008, 2011, 2014, and 2017; and for the following pollutants: 
SO2, NOX, PM10, PM2.5, 
VOCs, CO, and NH3. New Hampshire also provided a summary of 
SO2 and NOx emissions for AMPD sources for the years of 
2016, 2017, 2018, and 2019.
---------------------------------------------------------------------------

    \90\ AMPD sources are facilities that participate in EPA's 
emission trading programs. The majority of AMPD sources are electric 
generating units (EGUs).
---------------------------------------------------------------------------

    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. New Hampshire relied on the MANE-VU 2028 
emissions projections for MANE-VU states. 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

[[Page 80677]]

the MANE-VU Asks.\91\ New Hampshire's SIP submittal also includes a 
commitment to update the statewide emissions inventory periodically.
---------------------------------------------------------------------------

    \91\ See ``OTC MANE-VU 2011 Based Modeling Platform Support 
Document October 2018--Final.'' At https://otcair.org/manevu/document.asp?fview=Reports.
---------------------------------------------------------------------------

    The EPA proposes to find that New Hampshire has met the 
requirements of 40 CFR 51.308(f)(6) as described above, including 
through its continued participation in the IMPROVE network and the 
MANE-VU RPO and its on-going compliance with the AERR, and that no 
further elements are necessary at this time for New Hampshire to assess 
and report on visibility pursuant to 40 CFR 51.308(f)(6)(vi).

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 applicable RPGs 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. 
Sections 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, 
Sec.  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 that 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.
    New Hampshire's submission describes the status of measures of the 
long-term strategy from the first implementation period. As a member of 
MANE-VU, New Hampshire considered the MANE-VU Asks and adopted 
corresponding measures into its long-term strategy for the first 
implementation period. The MANE-VU Asks were: (1) Timely implementation 
of Best Available Retrofit Technology (BART) requirements; (2) EGU 
controls including Controls at 167 Key Sources that most affect MANE-VU 
Class I areas; (3) Low sulfur fuel oil strategy; and (4) Continued 
evaluation of other control measures. New Hampshire met all the 
identified reasonable measures requested during the first 
implementation period. During the first planning period for regional 
haze, programs that were put in place focused on reducing sulfur 
dioxide (SO2) emissions. The reductions achieved led to vast 
improvements in visibility at the MANE-VU Federal Class I Areas due to 
reduced sulfates formed from SO2 emissions. New Hampshire 
lists in its submission an expansive list of control measures that help 
control the emissions of VOCs, NOX, PM and SO2 
from a wide range of sources.\92\ New Hampshire's SIP submission 
includes emission data demonstrating the reductions achieved throughout 
the state through implementation of the measures mentioned. The state 
included periodic emission data that demonstrate a decrease in VOCs, 
NOX, PM and SO2 emissions throughout the state. 
The measured visibility improvement from emission reductions at the two 
New Hampshire EGUs that were subjected to BART and other targeted 
strategies showed drastic emission decreases from 2007-2017 for 
SO2, NOX and particulate matter.\93\
---------------------------------------------------------------------------

    \92\ See Section 5.1 of the NH Regional Haze SIP--Final May 
2022.
    \93\ See Figure 5-1: ``Emissions in SO2, 
NOX and PM from Two New Hampshire EGUs, 2007-2017 
(tpy)''in the New Hampshire SIP submission.
---------------------------------------------------------------------------

    The EPA proposes to find that New Hampshire 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.
    New Hampshire's SIP submission includes the assessments of 
visibility conditions and changes at the State's class I areas, 
expressed in terms of 5-year averages, required by section 
51.308(f)(3). In particular, New Hampshire's submission reports current 
(2015-2019) visibility conditions for the most impaired and clearest 
days of 12.33 and 4.69 deciviews, respectively, indicating that haze 
index levels have decreased by 9.55 deciviews on the most impaired days 
and 2.96 deciviews on the clearest days from baseline visibility 
conditions (2000-2004).\94\ The SIP submission also indicates that, 
since the period addressed in New Hampshire's previous progress report 
(2009-2013), haze index levels have decreased by 3.07 and 1.18 
deciviews on the most impaired and clearest days, respectively. EPA 
therefore proposes to find that New Hampshire has satisfied the 
requirements of 40 CFR 51.308(g)(3).
---------------------------------------------------------------------------

    \94\ See Section 5.3 of the New Hampshire SIP submission.
---------------------------------------------------------------------------

    Pursuant to Sec.  51.308(g)(4), New Hampshire provided a summary of 
emissions of NOX, SO2, PM10, 
PM2.5, VOCs, 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 2017, based on 
emission inventory information submitted pursuant to the AERR in 40 CFR 
part 51, subpart A. With respect to sources that report directly to the 
EPA, New Hampshire also included AMPD data for SO2 and 
NOX emissions for 2016 through 2019.
    The reductions achieved by New Hampshire emission control measures 
are seen in the emissions inventory. Based on New Hampshire's SIP 
submission, NOX emissions have continuously declined in New 
Hampshire from 2002 through 2017, especially in the point, nonroad and 
onroad mobile sectors. NOX emissions are expected to 
continue to decrease as fleet turnover occurs and the older more 
polluting vehicles and equipment are replaced by newer, cleaner ones. 
New Hampshire sources that report to the EPA's AMPD showed a decline in 
NOX emissions in the period since the last progress report 
(2,753 tons in 2014 and 1,018 tons in 2019).\95\
---------------------------------------------------------------------------

    \95\ See Figure 5-4 ``NOX Emissions in New Hampshire 
for all Data Categories, 2002-2017 (tpy)'' and Figure 5-7: ``MANE-VU 
State NOX Emissions from AMPD, 2016-2019 (tpy)''in the 
New Hampshire SIP submission.
---------------------------------------------------------------------------

    Emissions of SO2 have shown a steady significant decline 
in New Hampshire over the period 2002 to 2017, particularly in the 
point, nonroad and onroad mobile sectors. Large decreases

[[Page 80678]]

are attributable to the installation of scrubbers at Merrimack Station, 
which became operational in late 2011, and to New Hampshire's adoption 
of the MANE-VU low sulfur fuel strategy.\96\ Since some components of 
the low sulfur fuel strategy have milestones of 2016 and 2018, and as 
MANE-VU states continue to adopt rules to implement the strategy, 
additional SO2 emissions reductions have likely been 
obtained since 2017 and are expected to continue into the future. Other 
SO2 emissions decreases are due to fuel switching due to the 
availability of less expensive natural gas in recent years, and the 
reduction of use of coal-fired EGUs at Merrimack and Schiller Station.
---------------------------------------------------------------------------

    \96\ NH SIP Submission at 88 (Figure 5-15); see also id. at 71-
72.
---------------------------------------------------------------------------

    New Hampshire's submission analyzes the change in PM10 
emissions from all NEI data categories point, nonpoint, non-road, and 
onroad in New Hampshire, noting that PM10 emissions have 
generally remained constant, particularly between the 2002/2008 
inventories and the 2011/2017 inventories. The apparent change in point 
source emissions of PM10 is due to a large point source in 
the State mistakenly reporting its PM10 emissions in pounds, 
rather than tons. The variations in the onroad category are due to 
changes in emission inventory calculation methodologies, which resulted 
in higher particulate matter estimates in the other years than in 2002. 
The large variation in emissions in the nonpoint category is due to 
changes in calculation methodologies for residential wood burning and 
fugitive dust categories, which have varied significantly.
    New Hampshire also analyzes PM2.5 emissions from all NEI 
data categories for the period from 2002 to 2017, noting that, similar 
to PM10 emissions, they have remained generally constant in 
New Hampshire. PM2.5 emissions show some decrease in the 
nonroad category for the period from 2002 to 2017 because of Federal 
new engine standards for nonroad vehicles and equipment. Overall, there 
is a decrease in onroad emissions due to Federal and State regulations, 
but the increase from 2002 to 2008 is due to changes in emission 
inventory calculation methodologies and a model change, as previously 
explained, which resulted in higher fine particulate matter estimates 
in the years after 2002. The variation in emissions in the nonpoint 
category is due to changes in calculation methodologies for residential 
wood burning and fugitive dust categories, which have varied 
significantly.
    Figure 5-20 of New Hampshire's submission shows VOC emissions from 
all NEI data categories for the period 2002 to 2017 in New Hampshire. 
VOC emissions have shown a decline in New Hampshire over the period 
2002 to 2017. Much of the decrease in VOC is attributable to Federal 
and state rules for evaporative sources of VOC emissions such as 
portable fuel containers; architectural, industrial, and maintenance 
coatings; consumer products; and solvent degreasing. VOC emissions from 
non-road and on-road mobile sources are expected to continue to 
decrease as older, more polluting vehicles are replaced by newer, 
cleaner ones.
    Figure 5-23 of New Hampshire's submission shows ammonia 
(NH3) emissions from all NEI data categories for the period 
2002 to 2017 and show a general downward trend in New Hampshire. 
Ammonia decreases were achieved in the onroad sectors due to Federal 
new engine standards for vehicles and equipment. Point source increases 
from 2002 to 2008 are due to reporting, grouping and methodology 
changes, not actual emission increases. Nonpoint increases and 
decreases from 2002 to 2017 are due to reporting, grouping and 
methodology changes. For many MANE-VU states, ammonia emissions for 
2014 and 2017 are lower than they were for earlier years. Most MANE-VU 
states saw increases in 2017 relative to 2014; this could likely be the 
result of estimation methodology changes. Emissions from 2002-2008 are 
not comparable to post-2008 emissions due to methodology changes.
    The EPA is proposing to find that New Hampshire has satisfied the 
requirements of Sec.  51.308(g)(4) by providing emissions information 
for NOX, SO2, PM10, PM2.5, 
VOCs, and NH3 broken down by type of source.
    The emissions trend data in the SIP submission \97\ supports New 
Hampshire's assessment that no significant increase of haze-causing 
pollutant emissions has occurred in New Hampshire during the reporting 
period and that changes in emissions have not limited or impeded 
progress in reducing pollutant emissions and improving visibility. New 
Hampshire notes that, both within and outside the State, there has been 
a shift to cleaner generation of electricity using natural gas in place 
of fuels such as coal or oil that has contributed to reduced emissions 
of haze-causing pollutants. The EPA is proposing to find that New 
Hampshire has met the requirements of Sec.  51.308(g)(5).
---------------------------------------------------------------------------

    \97\ See Chapter 5 ``Progress Report and Periodic Reports'' in 
New Hampshire SIP submission.
---------------------------------------------------------------------------

I. Requirements for State and Federal Land Manager Coordination

    Section 169A(d) of the Clean Air Act requires states to consult 
with FLMs before holding the public hearing on a proposed regional haze 
SIP, and to include a summary of the FLMs' conclusions and 
recommendations in the notice to the public. In addition, section 
51.308(i)(2)'s FLM consultation provision requires a state to provide 
FLMs with an opportunity for consultation that is early enough in the 
state's policy analyses of its emission reduction obligation so that 
information and recommendations provided by the FLMs can meaningfully 
inform the state's decisions on its long-term strategy. 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. Regardless, 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) further 
provides that FLMs must be given an opportunity to discuss their 
assessment of visibility impairment in any Class I area and their 
recommendations on the development and implementation of strategies to 
address visibility impairment. Section 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. New 
Hampshire participated in these consultation meetings and calls.\98\
---------------------------------------------------------------------------

    \98\ See Appendix G ``MANE-VU Regional Haze Consultation Report 
and Consultation Documentation--Final.''
---------------------------------------------------------------------------

    As part of this early engagement with the FLMs, on April 12, 2018, 
the U.S National Park Service (NPS) sent letters to the MANE-VU states 
requesting that they consider specific individual

[[Page 80679]]

sources in their long-term strategies.\99\ NPS used an analysis of 
emissions divided by distance (Q/d) to estimate the impact of MANE-VU 
facilities. To select the facilities, NPS first summed 2014 NEI 
NOX, PM10, SO2, and SO4 
emissions and divided by the distance to a specified NPS mandatory 
Class I Federal area. NPS summed the Q/d values across all MANE-VU 
states relative to Acadia, Mammoth Cave and Shenandoah National Parks, 
ranked the Q/d values relative to each Class I area, created a running 
total, and identified those facilities contributing to 80% of the total 
impact at each NPS Class I area. NPS merged the resulting lists of 
facilities and sorted them by their states. NPS suggested that a state 
consider those facilities comprising 80% of the Q/d total, not to 
exceed the 25 top ranked facilities. The NPS originally identified five 
facilities in New Hampshire in this letter.\100\ New Hampshire included 
the NPS initial letter in their proposed SIP. In a subsequent letter 
dated October 22, 2018, NPS identified four facilities for which more 
control information was desired. New Hampshire detailed the emission 
controls and updates to the four facilities to address the NPS's 
request for more information, as discussed previously.\101\
---------------------------------------------------------------------------

    \99\ Id.
    \100\ Id.
    \101\ See Appendix W email from NPS to NHDES.
---------------------------------------------------------------------------

    On June 9, 2021, the NPS Air Resources Division (ARD) and NPS 
Interior Region 1 staff hosted a consultation meeting with New 
Hampshire Department of Environmental Services (NHDES) to discuss a 
draft of the New Hampshire Regional Haze SIP. Representatives from the 
U.S. Forest Service and U.S. Fish & Wildlife Service also attended the 
meeting.\102\ On June 11, 2021, the NPS sent a summary of this meeting 
and NPS' comments to New Hampshire via email, stating that the NPS 
``commend[s] the state on its level of analysis and commitment to 
emissions reductions.'' \103\ On June 16, 2021, the U.S. Forest Service 
indicated by letter that it was ``satisfied with the document as 
provided and offer[ed] no suggestions for change.'' \104\ In accordance 
with CAA Sec.  169A(d) and 40 CFR 51.308(i)(3), New Hampshire included 
summaries of the consultation and copies of the FLM correspondence in 
appendices G and W of the SIP submission. New Hampshire also noted that 
it has responded to FLM feedback on the selection and evaluation of 
specific sources potentially impacting visibility in Class I areas 
during development of the SIP submission and, as a result, expanded the 
number of sources evaluated to ensure a robust analysis and adequate 
controls to improve visibility.\105\
---------------------------------------------------------------------------

    \102\ See NH SIP Submittal, App. W (Email from H. Salazar, Reg'l 
Air Res. Coord., NPS, to C. Beahm, Air Res. Div., NHDES (June 11, 
2021)).
    \103\ Id.
    \104\ Id. (Ltr. from D. Ibarguen, Forest Supervisor, White Mtn. 
Nat'l Forest, to C. Wright, Air Res. Div. Dir., NHDES (June 16, 
2021)).
    \105\ NH SIP Submittal, App. W.
---------------------------------------------------------------------------

    New Hampshire held two public comment periods and one public 
hearing related to this Regional Haze SIP Revision. On November 4, 
2019, NHDES published a notice in the Manchester, NH, Union Leader 
announcing a 30-day public comment period providing for submission of 
written comments and allowing any member of the public the opportunity 
to request a public hearing on the SIP revision. A second public notice 
period was conducted starting on December 10, 2021 (and extended on 
December 27, 2021), with published notices in the Union Leader. A 
public hearing was held in Room 208C at NHDES Offices in Concord, NH 
and online via WebEx at 1:30 p.m. on February 23, 2022.
    For the reasons stated above, the EPA proposes to find that New 
Hampshire has satisfied the requirements under CAA section 169A(d) and 
40 CFR 51.308(i) regarding consultation with the FLMs on its regional 
haze SIP for the second implementation period.
    New Hampshire's May 5, 2022, SIP submission includes a commitment 
to revise and submit a subsequent regional haze SIP by July 21, 2033, 
and every ten years thereafter. The state's commitment includes 
submitting periodic progress reports in accordance with Sec.  51.308(f) 
and a commitment to evaluate progress towards the reasonable progress 
goal for 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 in accordance 
with Sec.  51.308(g).\106\
---------------------------------------------------------------------------

    \106\ See the preface and Chapter 9 of the ``NH Regional Haze 
SIP--Final March 2022.''
---------------------------------------------------------------------------

V. Proposed Action

    The EPA is proposing to approve New Hampshire's May 5, 2022, 
supplemented on September 21, 2023, SIP submission as satisfying the 
regional haze requirements for the second implementation period 
contained in 40 CFR 51.308(f). Additionally, EPA is proposing to 
approve the revised state rule Env-A 2300, ``Mitigation of Regional 
Haze,'' into the SIP.

VI. Incorporation by Reference

    In this rule, the EPA is proposing to include in a final EPA rule 
regulatory text that includes incorporation by reference. In accordance 
with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by 
reference New Hampshire's Env-A 2300 ``Mitigation of Regional Haze,'' 
which contains updated emissions limits for certain facilities located 
in the State. The EPA has made, and will continue to make, these 
documents generally available through https://www.regulations.gov and 
at the EPA Region 1 Office (please contact the person identified in the 
FOR FURTHER INFORMATION CONTACT section of this preamble for more 
information).

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 proposes to approve 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 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001); and
     Is not subject to requirements of Section 12(d) of the 
National

[[Page 80680]]

Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) 
because application of those requirements would be inconsistent with 
the CAA.
    In addition, this proposed rulemaking action, pertaining to New 
Hampshire regional haze SIP submission for the second planning period, 
is not approved to apply on any Indian reservation land or in any other 
area where the EPA or an Indian tribe has demonstrated that a tribe has 
jurisdiction. In those areas of Indian country, the rule does not have 
tribal implications and will not impose substantial direct costs on 
tribal governments or preempt tribal law as specified by Executive 
Order 13175 (65 FR 67249, November 9, 2000).
    Executive Order 12898 (Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations, 59 FR 7629, 
Feb. 16, 1994) directs Federal agencies to identify and address 
``disproportionately high and adverse human health or environmental 
effects'' of their actions on minority populations and low-income 
populations to the greatest extent practicable and permitted by law. 
EPA defines environmental justice (EJ) as ``the fair treatment and 
meaningful involvement of all people regardless of race, color, 
national origin, or income with respect to the development, 
implementation, and enforcement of environmental laws, regulations, and 
policies.'' EPA further defines the term fair treatment to mean that 
``no group of people should bear a disproportionate burden of 
environmental harms and risks, including those resulting from the 
negative environmental consequences of industrial, governmental, and 
commercial operations or programs and policies.'' The air agency did 
not evaluate environmental justice considerations as part of its SIP 
submittal; the CAA and applicable implementing regulations neither 
prohibit nor require such an evaluation. EPA did not perform an EJ 
analysis and did not consider EJ in this action. Consideration of EJ is 
not required as part of this action, and there is no information in the 
record inconsistent with the stated goal of E.O. 12898 of achieving 
environmental justice for people of color, low-income populations, and 
Indigenous peoples.

List of Subjects in 40 CFR Part 52

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

    Dated: November 13, 2023.
David Cash,
Regional Administrator, EPA Region 1.
[FR Doc. 2023-25336 Filed 11-17-23; 8:45 am]
BILLING CODE 6560-50-P