Home/Federal/Federal Register/2023-25336

Proposed Rule2023-25336

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

Primary source

Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.

Published

November 20, 2023

Issuing agencies

Environmental Protection Agency

Abstract

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.

Full Text

<html>
<head>
<title>Federal Register, Volume 88 Issue 222 (Monday, November 20, 2023)</title>
</head>
<body><pre>
[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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
<a href="https://www.regulations.gov">https://www.regulations.gov</a>. For comments submitted at <a href="http://Regulations.gov">Regulations.gov</a>,
follow the online instructions for submitting comments. Once submitted,
comments cannot be edited or removed from <a href="http://Regulations.gov">Regulations.gov</a>. 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 <a href="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a>.

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 <a href="/cdn-cgi/l/email-protection#0c7e6d6f676d797f676d7f22697e656f4c697c6d226b637a">[email&#160;protected]</a>.

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 (SO<INF>2</INF>), nitrogen oxides (NO<INF>X</INF>), and, in
some cases, volatile organic compounds (VOC) and ammonia
(NH<INF>3</INF>)). Fine particle precursors react in the atmosphere to
form fine particulate matter (PM<INF>2.5</INF>), 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, <a href="https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period">https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period</a>, 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. <a href="https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period">https://www.epa.gov/visibility/guidance-regional-haze-state-implementation-plans-second-implementation-period</a> 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. <a href="https://www.epa.gov/system/files/documents/2021-07/clarifications-regarding-regional-haze-state-implementation-plans-for-the-second-implementation-period.pdf">https://www.epa.gov/system/files/documents/2021-07/clarifications-regarding-regional-haze-state-implementation-plans-for-the-second-implementation-period.pdf</a>. 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. <a href="https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional">https://www.epa.gov/visibility/technical-guidance-tracking-visibility-progress-second-implementation-period-regional</a> 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. <a href="https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program">https://www.epa.gov/visibility/memo-and-technical-addendum-ambient-data-usage-and-completeness-regional-haze-program</a> 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
<a href="https://www3.epa.gov/ttnamti1/files/ambient/visible/tracking.pdf">https://www3.epa.gov/ttnamti1/files/ambient/visible/tracking.pdf</a>.
---------------------------------------------------------------------------

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
SO<INF>2</INF> and NO<INF>X</INF> 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 SO<INF>2</INF>
emissions and resultant particulate sulfate contributions to visibility
impairment, some also incorporated NO<INF>X</INF> 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 SO<INF>2</INF> and
NO<INF>X</INF>. The list of EGUs was based on an enhanced ``Q/d''
analysis \36\ that considered recent SO<INF>2</INF> 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 SO<INF>2</INF>
emissions. This list of sources was then enhanced by including the top
five SO<INF>2</INF> 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 SO<INF>2</INF> emissions and used cumulative
SO<INF>2</INF> 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 (C<INF>i</INF>), 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 NO<INF>X</INF> 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
SO<INF>2</INF> 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 SO<INF>2</INF>
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,
NO<INF>X</INF> emissions have begun to play a more significant role in
visibility impacts in recent years as SO<INF>2</INF> 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.
---------------------------------------------------------------------------

<bullet> 2016 Updates to the Assessment of Reasonable Progress for
Regional Haze in MANE-VU Class I Areas (Appendix L NH);
<bullet> Impact of Wintertime SCR/SNCR Optimization on Visibility
Impairing Nitrate Precursor Emissions. November 2017. (Appendix Q NH);
<bullet> High Electric Demand Days and Visibility Impairment in
MANE-VU. December 2017. (Appendix R NH);
<bullet> Benefits of Combined Heat and Power Systems for Reducing
Pollutant Emissions in MANE-VU States. March 2016. (Appendix S NH);
<bullet> 2016 MANE-VU Source Contribution Modeling Report--CALPUFF
Modeling of Large Electrical Generating Units and Industrial Sources
April 4, 2017 (Appendix C NH);
<bullet> Contribution Assessment Preliminary Inventory Analysis.
October 10, 2016. (Appendix D NH);
<bullet> Four-Factor Data Collection Memo. March 2017. (Appendix K
NH);
<bullet> 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 SO<INF>2</INF> and/or NO<INF>X</INF>] 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 SO<INF>2</INF>
or NO<INF>X,</INF> 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 SO<INF>2</INF> 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
NO<INF>X</INF> and/or SO<INF>2</INF> 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 NO<INF>X</INF> at
the time of the facility's initial permitting; hence, the
NO<INF>X</INF> 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 NO<INF>X</INF>

[[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 SO<INF>2</INF> emissions to 0.012 lbs/MMBtu.
Essential Power Newington was subject to NNSR for NO<INF>X</INF> at
the time of initial permitting in July 2010; these NO<INF>X</INF>
limits were established as LAER-based limits. The Newington units use
dry low NO<INF>X</INF> (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 SO<INF>2</INF> at the time of their initial permitting; these
SO<INF>2</INF> 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 NO<INF>X</INF> and
SO<INF>2</INF> emissions on a year-round basis.
The units at Granite Ridge Energy were subject to NNSR for
NO<INF>X</INF> 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 SO<INF>2</INF> 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 NO<INF>X</INF> and SO<INF>2</INF> 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 NO<INF>X</INF>
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 NO<INF>X</INF> 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 NO<INF>X</INF> 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
NO<INF>X</INF> 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 NO<INF>X</INF> and SO<INF>2</INF>
emissions. On May 3, 2018, NHDES requested information from GSP
regarding NO<INF>X</INF> 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 NO<INF>X</INF> and SO<INF>2</INF> for MK1 and MK2. After
review, NHDES concluded the analysis validates the continued use of
current enforceable measures for both SO<INF>2</INF> and
NO<INF>X</INF>. 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 NO<INF>X</INF> 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 NO<INF>X</INF> 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 NO<INF>X</INF>
RACT Emission Limits for MK1 and MK2 Over Time'' of the NH RH SIP,
Final 2022.
\63\ Env-A 2300 incorporates by reference NO<INF>X</INF> 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 NO<INF>X</INF> RACT limits applicable
to coal-fired cyclone boilers. See 88 FR 60893 (September 6, 2023).
EPA will issue a decision on New Hampshire's NO<INF>X</INF> 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 NO<INF>X</INF> RACT Orders RO-003 and ARD-06-001
which limit NO<INF>X</INF> and SO<INF>2</INF> emissions. NHDES
requested additional information from GSP regarding both NO<INF>X</INF>
RACT and Regional Haze Rule requirements associated with the MANE-VU
``Ask.'' For SR4 and SR6, NHDES requested that GSP conduct a
NO<INF>X</INF> 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
NO<INF>X</INF> emission levels. Also, GSP was requested to evaluate the
most effective use of the DSI systems on SR4 and SR6 for SO<INF>2</INF>
emission reductions. For ``Ask 1'' regarding SR5, NHDES requested GSP
evaluate the most effective use of the SNCR for NO<INF>X</INF> emission
reductions and the limestone injection system for SO<INF>2</INF>
emission reductions. GSP provided analyses to demonstrate that
operation of low NO<INF>X</INF> burners (LNB) and OFA on SR4 and SR6
were sufficient to achieve an emission limit of 0.25 lbs
NO<INF>X</INF>/MMBtu and that year-round operation of the SNCR would
not result in any additional emissions reductions. NHDES issued
NO<INF>X</INF> RACT Order RO-003 on September 6, 2018, which
established a NO<INF>X</INF> 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 NO<INF>X</INF> 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 SO<INF>2</INF> 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 SO<INF>2</INF> 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
NO<INF>X</INF> RACT emission limits and the NO<INF>X</INF> and
SO<INF>2</INF> 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
NO<INF>X</INF> emissions. GSP operates the water injection system on
NT1 as necessary to maintain compliance with the NO<INF>X</INF>
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 NO<INF>X</INF> 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'' SO<INF>2</INF> controls and therefore Ask 1
applies only to its NO<INF>X</INF> emissions. NHDES determined that the
existing pollution control equipment (LNB, OFA and water injection
system) installed on NT1 combined with the federally enforceable
NO<INF>X</INF> 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, ``NO<INF>X</INF>
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 NO<INF>X</INF> and SO<INF>2</INF>
emissions. MK1 and MK2 are cyclone-firing, wet-bottom utility boilers
that burn bituminous coal and are each equipped with SCR for
NO<INF>X</INF> 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 (SO<INF>2</INF> 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 NO<INF>X</INF> and
SO<INF>2</INF>, which, for NO<INF>X</INF>, included review of fuel
switching, OFA, SNCR, reburn, and upgrades to the existing SCR and, for
SO<INF>2</INF>, 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 NO<INF>X</INF> emissions and
that the existing FGD system already achieves a 95% reduction in
SO<INF>2</INF> 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 SO<INF>2</INF>
and NO<INF>X</INF>, 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 SO<INF>2</INF> 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 NO<INF>X</INF>, SO<INF>2</INF>, 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 NO<INF>X</INF>
emissions for peaking combustion turbines that have the potential to
operate on high electric demand days'' by either: (1) Meeting
NO<INF>X</INF> 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
NO<INF>X</INF> emission standards of no greater than 25 ppm for natural
gas and 42 ppm for fuel oil, or at a minimum, NO<INF>X</INF> 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 NO<INF>X</INF> emission controls at these
units, which indicated no additional NO<INF>X</INF> 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 NO<INF>X</INF> emissions and
specifications. Additionally, GSP has pledged to continue employing
good combustion practices to optimize their NO<INF>X</INF> 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: <a href="https://www.energy.nh.gov/renewable-energy/regional-greenhouse-gas-initiative">https://www.energy.nh.gov/renewable-energy/regional-greenhouse-gas-initiative</a>.
---------------------------------------------------------------------------

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 NO<INF>X</INF> 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 SO<INF>2</INF> and NO<INF>X</INF> 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 SO<INF>2</INF> include coal-fired EGUs,
industrial boilers, oil-fired EGUs, and oil-fired area sources
including residential, commercial, and industrial sources. Major-
emitting sources of NO<INF>X</INF> include on-road vehicles, non-road
vehicles, and EGUs.\67\ The RPO's documentation explains that ``[EGUs]
emitting SO<INF>2</INF> and NO<INF>X</INF> and industrial point sources
emitting SO<INF>2</INF> 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--SO<INF>2</INF> and
NO<INF>X</INF>--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 NO<INF>X</INF> 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 NO<INF>X</INF>
and/or SO<INF>2</INF> 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 NO<INF>X</INF> and SO<INF>2</INF> 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 NO<INF>X</INF> and
SO<INF>2</INF> emissions. MK1 and MK2 are each equipped with SCR for
NO<INF>X</INF> 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 (SO<INF>2</INF> and HCl) removal. While only Unit 2 was
identified by MANE-VU as contributing a 3.0 Mm<INF>-</INF>\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
NO<INF>X</INF> emissions and that the existing FGD system already
achieves a 95% reduction in SO<INF>2</INF> 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 NO<INF>X</INF> and SO<INF>2</INF>
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 <a href="https://www.nhpr.org/climate-change/2021-03-01/n-h-coal-plant-will-run-through-at-least-2025-after-latest-grid-auction">https://www.nhpr.org/climate-change/2021-03-01/n-h-coal-plant-will-run-through-at-least-2025-after-latest-grid-auction</a>; Union says Schiller
coal-fired power plant is shut for good, Granite Geek (Jan. 12,
2021), available at <a href="https://granitegeek.concordmonitor.com/2021/01/12/union-says-schiller-coal-fired-power-plant-is-shut-for-good/">https://granitegeek.concordmonitor.com/2021/01/12/union-says-schiller-coal-fired-power-plant-is-shut-for-good/</a>.
\78\ See <a href="https://www.ibew1837.org/content/schiller-station-closing-end-era">https://www.ibew1837.org/content/schiller-station-closing-end-era</a>, or see PDF version of this article in the docket.
\79\ See EPA's Clean Air Markets Program Data (CAMPD) at <a href="https://campd.epa.gov/data">https://campd.epa.gov/data</a>.
\80\ See <a href="https://www.iso-ne.com/markets-operations/markets/forward-capacity-market/">https://www.iso-ne.com/markets-operations/markets/forward-capacity-market/</a> to download ISO New England forward
capacity auction results. This spreadsheet has also been added to
the docket for this notice.
---------------------------------------------------------------------------

Ask 5 addresses NO<INF>X</INF> 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 NO<INF>X</INF> 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 NO<INF>X</INF> 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 NO<INF>X</INF> 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 NO<INF>X</INF> 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 NO<INF>X</INF> 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 SO<INF>2</INF> and NO<INF>X</INF> 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 SO<INF>2</INF> and
NO<INF>X</INF> within the state that would be expected to contribute to
visibility impairment have small emissions of NO<INF>X</INF> and
SO<INF>2</INF>, 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 SO<INF>2</INF> emissions
for fuels. The New Hampshire SIP submittal also includes Env-A 2300,
which lowers NO<INF>X</INF> emission limits for Stored Solar Tamworth
and incorporates by reference an updated Env-A 1300, which includes
lower NO<INF>X</INF> 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 NO<INF>X</INF>, SO<INF>2</INF>, PM, VOCs and NH3
and 2016-2019 Air Markets Program Data (AMPD) emissions for
NO<INF>X</INF> and SO<INF>2</INF>. 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 <a href="https://extension.unh.edu/resources/files/Resource001886_Rep2781.pdf">https://extension.unh.edu/resources/files/Resource001886_Rep2781.pdf</a>.
---------------------------------------------------------------------------

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:
SO<INF>2</INF>, NO<INF>X</INF>, PM<INF>10</INF>, PM<INF>2.5</INF>,
VOCs, CO, and NH3. New Hampshire also provided a summary of
SO<INF>2</INF> 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 <a href="https://otcair.org/manevu/document.asp?fview=Reports">https://otcair.org/manevu/document.asp?fview=Reports</a>.
---------------------------------------------------------------------------

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 (SO<INF>2</INF>) emissions. The reductions achieved led to vast
improvements in visibility at the MANE-VU Federal Class I Areas due to
reduced sulfates formed from SO<INF>2</INF> emissions. New Hampshire
lists in its submission an expansive list of control measures that help
control the emissions of VOCs, NO<INF>X</INF>, PM and SO<INF>2</INF>
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,
NO<INF>X</INF>, PM and SO<INF>2</INF> 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
SO<INF>2</INF>, NO<INF>X</INF> 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 SO<INF>2</INF>,
NO<INF>X</INF> 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 NO<INF>X</INF>, SO<INF>2</INF>, PM<INF>10</INF>,
PM<INF>2.5</INF>, VOCs, and NH<INF>3</INF> 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 SO<INF>2</INF> and
NO<INF>X</INF> 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, NO<INF>X</INF> emissions have continuously declined in New
Hampshire from 2002 through 2017, especially in the point, nonroad and
onroad mobile sectors. NO<INF>X</INF> 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
NO<INF>X</INF> 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 ``NO<INF>X</INF> Emissions in New Hampshire
for all Data Categories, 2002-2017 (tpy)'' and Figure 5-7: ``MANE-VU
State NO<INF>X</INF> Emissions from AMPD, 2016-2019 (tpy)''in the
New Hampshire SIP submission.
---------------------------------------------------------------------------

Emissions of SO<INF>2</INF> 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 SO<INF>2</INF> emissions reductions have likely been
obtained since 2017 and are expected to continue into the future. Other
SO<INF>2</INF> 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 PM<INF>10</INF>
emissions from all NEI data categories point, nonpoint, non-road, and
onroad in New Hampshire, noting that PM<INF>10</INF> emissions have
generally remained constant, particularly between the 2002/2008
inventories and the 2011/2017 inventories. The apparent change in point
source emissions of PM<INF>10</INF> is due to a large point source in
the State mistakenly reporting its PM<INF>10</INF> 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 PM<INF>2.5</INF> emissions from all NEI
data categories for the period from 2002 to 2017, noting that, similar
to PM<INF>10</INF> emissions, they have remained generally constant in
New Hampshire. PM<INF>2.5</INF> 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
(NH<INF>3</INF>) 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 NO<INF>X</INF>, SO<INF>2</INF>, PM<INF>10</INF>, PM<INF>2.5</INF>,
VOCs, and NH<INF>3</INF> 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
NO<INF>X</INF>, PM<INF>10</INF>, SO<INF>2</INF>, and SO<INF>4</INF>
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

[…truncated; see source link]

View on FederalRegister.gov →Plain-text source

Indexed from Federal Register on November 20, 2023.

This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.