[Federal Register Volume 77, Number 101 (Thursday, May 24, 2012)]
[Proposed Rules]
[Pages 30932-30953]
[FR Doc No: 2012-12640]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R01-OAR-2012-0025; A-1-FRL-9676-5]

Approval and Promulgation of Air Quality Implementation Plans;
Massachusetts; Regional Haze

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing approval of a revision to the Massachusetts
State Implementation Plan (SIP) that addresses regional haze for the
first planning period from 2008 through 2018. It was submitted by the
Massachusetts Department of Environmental Protection (MassDEP) on
December 30, 2011. EPA is also proposing to approve, through parallel
processing, a supplemental Regional Haze submittal, Proposed Revisions
to Massachusetts Regional Haze State Implementation Plan (SIP), which
was proposed by the MassDEP for public comment on February 17, 2012.
These submittals address the requirements of the Clean Air Act (CAA)
and EPA's rules that require States to prevent any future, and remedy
any existing, manmade impairment of visibility in mandatory Class I
areas (also referred to as the ``regional haze program''). States are
required to assure reasonable progress toward the national goal of

achieving natural visibility conditions in Class I areas.

DATES: Written comments must be received on or before June 25, 2012.

ADDRESSES: Submit your comments, identified by Docket ID Number EPA-
R01-OAR-2012-0025 by one of the following methods:
    1. www.regulations.gov: Follow the on-line instructions for
submitting comments.
    2. Email<EMAIL_ADDRESS>    3. Fax:<PHONE_NUMBER>.
    4. Mail: ``Docket Identification Number EPA-R01-OAR-2012-0025 Anne
Arnold, U.S. Environmental Protection Agency, EPA New England Regional
Office, Office of Ecosystem Protection, Air Quality Planning Unit, 5
Post Office Square--Suite 100, (Mail Code OEP05-2), Boston, MA 02109-
3912.
    5. Hand Delivery or Courier: Deliver your comments to: Anne Arnold,
Manager, Air Quality Planning Unit, U.S. Environmental Protection
Agency, EPA New England Regional Office, Office of Ecosystem
Protection, Air Quality Planning Unit, 5 Post Office Square--Suite 100,
(Mail Code OEP05-2), Boston, MA 02109-3912. Such deliveries are only
accepted during the Regional Office's normal hours of operation. The
Regional Office's official hours of business are Monday through Friday,
8:30 to 4:30, excluding legal holidays.
    Instructions: Direct your comments to Docket ID No. EPA-R01-OAR-
2012-0025. EPA's policy is that all comments received will be included
in the public docket without change and may be made available online at
www.regulations.gov, including any personal information provided,
unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit through www.regulations.gov, or
email, information that you consider to be CBI or otherwise protected.
The www.regulations.gov Web site is an ``anonymous access'' system,
which means EPA will not know your identity or contact information
unless you provide it in the body of your comment. If you send an email
comment directly to EPA without going through www.regulations.gov your
email address will be automatically captured and included as part of
the comment that is placed in the public docket and made available on
the Internet. If you submit an electronic comment, EPA recommends that
you include your name and other contact information in the body of your
comment and with any disk or CD-ROM you submit. If EPA cannot read your
comment due to technical difficulties and cannot contact you for
clarification, EPA may not be able to consider your comment. Electronic
files should avoid the use of special characters, any form of
encryption, and be free of any defects or viruses.
    Docket: All documents in the electronic docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, i.e., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, is not placed on the Internet and will be
publicly available only in hard copy form. Publicly available docket
materials are available either electronically in www.regulations.gov or
in hard copy at Office of Ecosystem Protection, U.S. Environmental
Protection Agency, EPA New England Regional Office, Office of Ecosystem
Protection, Air Quality Planning Unit, 5 Post Office Square--Suite 100,
Boston, MA. EPA requests that if at all possible, you contact the
contact listed in the FOR FURTHER INFORMATION CONTACT section to
schedule your inspection. The Regional Office's official hours of
business are Monday through Friday, 8:30 to 4:30, excluding legal
holidays.
    In addition, copies of the State submittal are also available for
public inspection during normal business hours, by appointment at the
Division of Air Quality Control, Department of Environmental
Protection, One Winter Street, 8th Floor, Boston, MA 02108.

FOR FURTHER INFORMATION CONTACT: Anne McWilliams, Air Quality Unit,
U.S. Environmental Protection Agency, EPA New England Regional Office,
5 Post Office Square--Suite 100, (Mail Code OEP05-02), Boston, MA
02109-3912, telephone number<PHONE_NUMBER>, fax number<PHONE_NUMBER>,
email<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Table of Contents

I. What is the background for EPA's proposed action?
    A. The Regional Haze Problem
    B. Background Information
    C. Roles of Agencies in Addressing Regional Haze
    D. The Relationship of the Clean Air Interstate Rule and the
Cross-State Air Pollution Rule to Regional Haze Requirements
II. What are the requirements for the Regional Haze SIPs?
    A. The CAA and the Regional Haze Rule (RHR)
    B. Determination of Baseline, Natural, and Current Visibility
Conditions
    C. Determination of Reasonable Progress Goals (RPGs)
    D. Best Available Retrofit Technology (BART)
    E. Long-Term Strategy (LTS)
    F. Coordinating Regional Haze and Reasonably Attributable
Visibility Impairment (RAVI) LTS
    G. Monitoring Strategy and Other Implementation Plan
Requirements
    H. Consultation With States and Federal Land Managers (FLMs)
III. What is EPA's analysis of Massachusetts' Regional Haze SIP
submittal?
    A. Massachusetts' Impact on MANE-VU Class I Areas
    B. Best Available Retrofit Technology
    1. Identification of all BART-Eligible Sources
    2. Cap-Outs
    3. Identification of Sources Subject to BART
    4. Modeling To Demonstrate Source Visibility Impact
    5. Source-Specific BART Determinations
    6. Identification of All BART Source Categories Covered by the
Alternative Program
    7. Determination of the BART Benchmark
    8. Massachusetts' SO2 Alternative BART Program
    9. Massachusetts' NOX Alternative BART Program
    10. EPA's Assessment of Massachusetts' Alternative to BART
Demonstration
    11. Massachusetts' PM BART Determinations
    12. BART Enforceability
    C. Long-Term Strategy
    1. Emissions Inventory for 2018 With Federal and State Control
Requirements
    2. Modeling To Support the LTS
    3. Relative Contributions of Pollutants to Visibility
Impairments
    4. Meeting the MANE-VU ``Ask''
    5. Additional Considerations for the LTS
    D. Consultation With States and Federal Land Managers
    E. Periodic SIP Revisions and Five-Year Progress Reports
IV. What action is EPA proposing to take?
V. Statutory and Executive Order Reviews

    Throughout this document, wherever ``we,'' ``us,'' or ``our'' is
used, we mean the EPA.

I. What is the background for EPA's proposed action?

A. The Regional Haze Problem

    Regional haze is visibility impairment that is produced by a
multitude of sources and activities which are located across a broad
geographic area and emit fine particles and their precursors (e.g.,
sulfur dioxide, nitrogen oxides, and in some cases, ammonia and
volatile organic compounds). Fine particle precursors react in the
atmosphere to form fine particulate matter (PM2.5) (e.g.,
sulfates, nitrates, organic carbon, elemental carbon, and soil dust),
which

also impair visibility by scattering and absorbing light. Visibility
impairment reduces the clarity, color, and visible distance that one
can see. PM2.5 can also cause serious health effects and
mortality in humans and contributes to environmental effects such as
acid deposition.
    Data from the existing visibility monitoring network, the
``Interagency Monitoring of Protected Visual Environments'' (IMPROVE)
monitoring network, show that visibility impairment caused by air
pollution occurs virtually all the time at most national park and
wilderness areas. The average visual range in many Class I areas (i.e.,
national parks and memorial parks, wilderness areas, and international
parks meeting certain size criteria) in the Western United States is
100-150 kilometers, or about one-half to two-thirds of the visual range
that would exist without manmade air pollution. In most of the eastern
Class I areas of the United States, the average visual range is less
than 30 kilometers, or about one-fifth of the visual range that would
exist under estimated natural conditions. See 64 FR 35715 (July 1,
1999).

B. Background Information

    In section 169A(a)(1) of the 1977 Amendments to the CAA, Congress
created a program for protecting visibility in the nation's national
parks and wilderness areas. This section of 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
\1\ which impairment results from manmade air pollution.'' On December
2, 1980, EPA promulgated regulations to address visibility impairment
in Class I areas that is ``reasonably attributable'' to a single source
or small group of sources, i.e., ``reasonably attributable visibility
impairment'' (RAVI). See 45 FR 80084 (Dec. 2, 1980). These regulations
represented the first phase in addressing visibility impairment. EPA
deferred action on regional haze that emanates from a variety of
sources until monitoring, modeling and scientific knowledge about the
relationships between pollutants and visibility impairment were
improved.
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    \1\ Areas designated as mandatory Class I Federal areas consist
of national parks exceeding 6,000 acres, wilderness areas and
national memorial parks exceeding 5,000 acres, and all international
parks that were in existence on August 7, 1977 (42 U.S.C. 7472(a)).
In accordance with section 169A of the CAA, EPA, in consultation
with the Department of Interior, promulgated a list of 156 areas
where visibility is identified as an important value (44 FR 69122,
November 30, 1979). The extent of a mandatory Class I area includes
subsequent changes in boundaries, such as park expansions (42 U.S.C.
7472(a)). Although States and Tribes may designate as Class I
additional areas which they consider to have visibility as an
important value, the requirements of the visibility program set
forth in section 169A of the CAA apply only to ``mandatory Class I
Federal areas.'' Each mandatory Class I Federal area is the
responsibility of a ``Federal Land Manager'' (FLM). (42 U.S.C.
7602(i)). When we use the term ``Class I area'' in this action, we
mean a ``mandatory Class I Federal area.''
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    Congress added section 169B to the CAA in 1990 to address regional
haze issues. EPA promulgated a rule to address regional haze on July 1,
1999 (64 FR 35714), the Regional Haze Rule. The Regional Haze Rule
revised the existing visibility regulations to integrate into the
regulation provisions addressing regional haze impairment and
established a comprehensive visibility protection program for Class I
areas. The requirements for regional haze, found at 40 CFR 51.308 and
51.309, are included in EPA's visibility protection regulations at 40
CFR 51.300-309. Some of the main elements of the regional haze
requirements are summarized in Section II. The requirement to submit a
regional haze SIP applies to all 50 States, the District of Columbia
and the Virgin Islands. In 40 CFR 51.308(b), States are required to
submit the first implementation plan addressing regional haze
visibility impairment no later than December 17, 2007. On January 15,
2009, EPA found that 37 States, the District of Columbia and the U.S.
Virgin Islands failed to submit this required implementation plan. See
74 FR 2392 (Jan. 15, 2009). In particular, EPA found that Massachusetts
failed to submit a plan that met the requirements of 40 CFR 51.308. See
74 FR 2393. On December 30, 2011, the Division of Air Quality Control
of the MassDEP submitted revisions to the Massachusetts SIP to address
regional haze as required by 40 CFR 51.308. In addition, on May 2,
2012, MassDEP requested parallel processing of its February 17, 2012
Proposed Revision to Massachusetts Regional Haze SIP. EPA has reviewed
Massachusetts' submittals and is proposing to find that they are
consistent with the requirements of 40 CFR 51.308 as outlined in
Section II.

C. Roles of Agencies in Addressing Regional Haze

    Successful implementation of the regional haze program will require
long-term regional coordination among States, tribal governments and
various federal agencies. As noted above, pollution affecting the air
quality in Class I areas can be transported over long distances, even
hundreds of kilometers. Therefore, to effectively address the problem
of visibility impairment in Class I areas, States need to develop
strategies in coordination with one another, taking into account the
effect of emissions from one jurisdiction on the air quality in
another.
    Because the pollutants that lead to regional haze can originate
from sources located across broad geographic areas, EPA has encouraged
the States and Tribes across the United States to address visibility
impairment from a regional perspective. Five regional planning
organizations (RPOs) were developed to address regional haze and
related issues. The RPOs first evaluated technical information to
better understand how their States and Tribes impact Class I areas
across the country, and then pursued the development of regional
strategies to reduce emissions of PM2.5 and other pollutants
leading to regional haze.
    The Mid-Atlantic/Northeast Visibility Union (MANE-VU) RPO 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 Northeastern United States. Member
State and Tribal governments include: Connecticut, Delaware, the
District of Columbia, Maine, Maryland, Massachusetts, New Hampshire,
New Jersey, New York, Pennsylvania, Penobscot Indian Nation, Rhode
Island, and Vermont.

D. The Relationship of the Clean Air Interstate Rule and the Cross-
State Air Pollution Rule to Regional Haze Requirements

    The Clean Air Interstate Rule (CAIR) required some states to reduce
emissions of SO2 and NOX that contribute to
violations of the 1997 National Ambient Air Quality Standards (NAAQS)
for PM2.5 and ozone. See 70 FR 25162 (May 12, 2005). CAIR
established emissions budgets for SO2 and NOX. On
October 13, 2006, EPA's ``Regional Haze Regulations; Revisions to
Provisions Governing Alternative to Source-Specific Best Available
Retrofit Technology (BART) Determinations; Final Rule'' (hereinafter
known as the ``Alternative to BART Rule'') was published in the Federal
Register. See 71 FR 60612. This rule establishes that states
participating in the CAIR program need not require BART for
SO2 and NOX at BART-eligible electric generating
units (EGUs). Many States relied on CAIR as an Alternative to BART for
SO2 and NOX for their subject EGUs.

    CAIR was later found to be inconsistent with the requirements of
the CAA and the rule was remanded to EPA. See North Carolina v. EPA,
550 F.3d 1176 (D.C. Cir. 2008). The court left CAIR in place until
replaced by EPA with a rule consistent with its opinion. See North
Carolina v. EPA, 550 F.3d 1176, 1178 (D.C. Cir. 2008).
    EPA promulgated the Cross-State Air Pollution Rule (CSAPR), to
replace CAIR in 2011 (76 FR 48208, August 8, 2011). Massachusetts was
subject to ozone season NOX controls under the CAIR program.
In its January 11, 2011, proposed Regional Haze SIP, MassDEP proposed
to rely on emission reductions included in EPA's proposed Transport
Rule as an Alternative to BART. However, Massachusetts is not subject
to any of the requirements of CSAPR and therefore cannot rely on CSAPR
as an Alternative to BART.
    On December 30, 2011, the D.C. Circuit Court issued an order
addressing the status of CSAPR and CAIR in response to motions filed by
numerous parties seeking a stay of CSAPR pending judicial review. In
that order, the D.C. Circuit stayed CSAPR pending the court's
resolutions of the petitions for review of that rule in EME Homer
Generation, L.P. v. EPA (No. 11-1302 and consolidated cases). The court
also indicated that EPA is expected to continue to administer CAIR in
the interim until the court rules on the petitions for review of CSAPR.
    On February 17, 2012, MassDEP proposed an amended Alternative to
BART. This strategy is discussed in further detail in Section III.B.
MassDEP has also requested parallel processing of sections 8.10, 8.11,
and 10.5, its revised BART and Long Term Strategy Chapters. Under this
procedure, EPA prepared this action before the State's final adoption
of this revision. Massachusetts has indicated that they plan to have a
final adopted submittal by July 2012, prior to our final action on its
Regional Haze SIP. After Massachusetts submits its final adopted
revision, EPA will review the submittal to determine whether it differs
from the proposed revision. If the final revision does differ from the
proposed revision, EPA will determine whether these differences are
significant. Based on EPA's determination regarding the significance of
any changes in the final revision, EPA would then decide whether it is
appropriate to prepare a final rule and describe the changes in the
final rulemaking action, re-propose action based on the Massachusetts'
final adopted revision, or take such other action as may be
appropriate.

II. What are the requirements for Regional Haze SIPs?

A. The CAA and the Regional Haze Rule (RHR)

    Regional haze SIPs must assure reasonable progress towards the
national goal of achieving natural visibility conditions in Class I
areas. Section 169A of the CAA and EPA's implementing regulations
require States to establish long-term strategies for making reasonable
progress toward meeting this goal. Implementation plans must also give
specific attention to certain stationary sources that were in existence
on August 7, 1977, but were not in operation before August 7, 1962, and
require these sources, where appropriate, to install Best Available
Retrofit Technology (BART) controls for the purpose of eliminating or
reducing visibility impairment. The specific regional haze SIP
requirements are discussed in further detail below.

B. Determination of Baseline, Natural, and Current Visibility
Conditions

    The RHR establishes the deciview (dv) as the principal metric for
measuring visibility. This visibility metric expresses uniform changes
in haziness in terms of common increments across the entire range of
visibility conditions, from pristine to extremely hazy conditions.
Visibility is determined by measuring the visual range (or deciview),
which is the greatest distance, in kilometers or miles, at which a dark
object can be viewed against the sky. The deciview is a useful measure
for tracking progress in improving visibility, because each deciview
change is an equal incremental change in visibility perceived by the
human eye. Most people can detect a change in visibility at one
deciview.\2\
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    \2\ The preamble to the RHR provides additional details about
the deciview. See 64 FR 35714, 35725 (July 1, 1999).
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    The deciview is used in expressing Reasonable Progress Goals (RPGs)
(which are interim visibility goals towards meeting the national
visibility goal), defining baseline, current, and natural conditions,
and tracking changes in visibility. The regional haze SIPs must contain
measures that ensure ``reasonable progress'' toward the national goal
of preventing and remedying visibility impairment in Class I areas
caused by manmade air pollution by reducing anthropogenic emissions
that cause regional haze. The national goal is a return to natural
conditions, i.e., manmade sources of air pollution would no longer
impair visibility in Class I areas.
    To track changes in visibility over time at each of the 156 Class I
areas covered by the visibility program and as part of the process for
determining reasonable progress, States must calculate the degree of
existing visibility impairment at each Class I area within the State at
the time of each regional haze SIP submittal and periodically review
progress every five years midway through each 10-year planning period.
To do this, the RHR requires States to determine the degree of
impairment (in deciviews) for the average of the 20 percent least
impaired (``best'') and 20 percent most impaired (``worst'') visibility
days over a specified time period at each of their Class I areas. In
addition, States must also develop an estimate of natural visibility
conditions for the purposes of comparing progress toward the national
goal. Natural visibility is determined by estimating the natural
concentrations of pollutants that cause visibility impairment and then
calculating total light extinction based on those estimates. EPA has
provided guidance to States regarding how to calculate baseline,
natural and current visibility conditions in documents entitled,
Guidance for Estimating Natural Visibility Conditions Under the
Regional Haze Rule, September 2003, (EPA-454/B-03-005) available at
www.epa.gov/ttncaaa1/t1/memoranda/rh_envcurhr_gd.pdf (hereinafter
referred to as ``EPA's 2003 Natural Visibility Guidance''), and
Guidance for Tracking Progress Under the Regional Haze Rule, September
2003 (EPA-454/B-03-004), available at www.epa.gov/ttncaaa1/t1/memoranda/rh_tpurhr_gd.pdf (hereinafter referred to as ``EPA's 2003
Tracking Progress Guidance'').
    For the first regional haze SIPs that were due by December 17,
2007, ``baseline visibility conditions'' were the starting points for
assessing ``current'' visibility impairment. Baseline visibility
conditions represent the degree of impairment for the 20 percent least
impaired days and 20 percent most impaired days at the time the
regional haze program was established. Using monitoring data from 2000
through 2004, States are required to calculate the average degree of
visibility impairment for each Class I area within the State, based on
the average of annual values over the five year period. The comparison
of initial baseline visibility conditions to natural visibility
conditions indicates the amount of improvement necessary to attain
natural visibility, while the future comparison of baseline conditions
to the then current conditions will indicate the

amount of progress made. In general, the 2000-2004 baseline period is
considered the time from which improvement in visibility is measured.

C. Determination of Reasonable Progress Goals (RPGs)

    The vehicle for ensuring continuing progress towards achieving the
natural visibility goal is the submission of a series of regional haze
SIPs from the States that establish RPGs for Class I areas for each
(approximately) 10-year planning period. The RHR does not mandate
specific milestones or rates of progress, but instead calls for States
to establish goals that provide for ``reasonable progress'' toward
achieving natural (i.e., ``background'') visibility conditions for
their Class I areas. In setting RPGs, States must provide for an
improvement in visibility for the most impaired days over the
(approximately) 10-year period of the SIP, and ensure no degradation in
visibility for the least impaired days over the same period.
    States have significant discretion in establishing RPGs, but are
required to consider the following factors established in the CAA and
in EPA's RHR: (1) The costs of compliance; (2) the time necessary for
compliance; (3) the energy and non-air quality environmental impacts of
compliance; and (4) the remaining useful life of any potentially
affected sources. States must demonstrate in their SIPs how these
factors are considered when selecting the RPGs for the best and worst
days for each applicable Class I area. See 40 CFR 51.308(d)(1)(i)(A).
States have considerable flexibility in how they take these factors
into consideration, as noted in EPA's July 1, 2007 memorandum from
William L. Wehrum, Acting Administrator for Air and Radiation, to EPA
Regional Administrators, EPA Regions 1-10, entitled Guidance for
Setting Reasonable Progress Goals Under the Regional Haze Program (p.
4-2, 5-1) (EPA's Reasonable Progress Guidance). In setting the RPGs,
States must also consider the rate of progress needed to reach natural
visibility conditions by 2064 (referred to as the ``uniform rate of
progress'' or the ``glide path'') and the emission reduction measures
needed to achieve that rate of progress over the 10-year period of the
SIP. The year 2064 represents a rate of progress which States are to
use for analytical comparison to the amount of progress they expect to
achieve. In setting RPGs, each State with one or more Class I areas
(``Class I State'') must also consult with potentially ``contributing
States,'' i.e., other nearby States with emission sources that may be
contributing to visibility impairment at the Class I State's areas. See
40 CFR 51.308(d)(1)(iv).

D. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs States to evaluate the use of
retrofit controls at certain larger, often uncontrolled, older
stationary sources in order to address visibility impacts from these
sources. Specifically, the CAA requires States to revise their SIPs to
contain such measures as may be necessary to make reasonable progress
towards the natural visibility goal, including a requirement that
certain categories of existing stationary sources built between 1962
and 1977 procure, install, and operate the ``Best Available Retrofit
Technology'' as determined by the State. CAA Sec.  169A(b)(2), 42
U.S.C. 7491(b)(2).\3\ States are directed to conduct BART
determinations for such sources that may be anticipated to cause or
contribute to any visibility impairment in a Class I area. Rather than
requiring source-specific BART controls, States also have the
flexibility to adopt an emissions trading program or other alternative
program as long as the alternative provides greater reasonable progress
towards improving visibility than BART.
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    \3\ The set of ``major stationary sources'' potentially subject
to BART are listed in CAA section 169A(g)(7).
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    On July 6, 2005, EPA published the Guidelines for BART
Determinations Under the Regional Haze Rule at Appendix Y to 40 CFR
part 51 (hereinafter referred to as the ``BART Guidelines'') to assist
States in determining which of their sources should be subject to the
BART requirements and in determining appropriate emission limits for
each applicable source. In making a BART applicability determination
for a fossil fuel-fired electric generating plant with a total
generating capacity in excess of 750 megawatts (MW), a State must use
the approach set forth in the BART Guidelines. A State is encouraged,
but not required, to follow the BART Guidelines in making BART
determinations for other types of sources.
    States must address all visibility impairing pollutants emitted by
a source in the BART determination process. The most significant
visibility impairing pollutants are sulfur dioxide (SO2),
nitrogen oxides (NOX), and particulate matter (PM). EPA has
stated that States should use their best judgment in determining
whether volatile organic compounds (VOCs), or ammonia (NH3)
and ammonia compounds impair visibility in Class I areas.
    The RPOs provided air quality modeling to the States to help them
in determining whether potential BART sources can be reasonably
expected to cause or contribute to visibility impairment in a Class I
area. Under the BART Guidelines, States may select an exemption
threshold value for their BART modeling, below which a BART eligible
source would not be expected to cause or contribute to visibility
impairment in any Class I area. The State must document this exemption
threshold value in the SIP and must state the basis for its selection
of that value. Any source with emissions that model above the threshold
value would be subject to a BART determination review. The BART
Guidelines acknowledge varying circumstances affecting different Class
I areas. States should consider the number of emission sources
affecting the Class I areas at issue and the magnitude of the
individual sources' impacts. Any exemption threshold set by the State
should not be higher than 0.5 deciviews. See 70 FR 39161 (July 6,
2005).
    In their SIPs, States must identify potential BART sources,
described as ``BART-eligible sources'' in the RHR, and document their
BART control determination analyses. The term ``BART-eligible source''
used in the BART Guidelines means the collection of individual emission
units at a facility that together comprises the BART-eligible source.
See 70 FR 39161 (July 6, 2005). In making BART determinations, section
169A(g)(2) of the CAA requires that States consider the following
factors: (1) The costs of compliance; (2) the energy and non-air
quality environmental impacts of compliance; (3) any existing pollution
control technology in use at the source; (4) the remaining useful life
of the source; and (5) the degree of improvement in visibility which
may reasonably be anticipated to result from the use of such
technology. States are free to determine the weight and significance to
be assigned to each factor. See 70 FR 39170 (July 6, 2005).
    A regional haze SIP must include source-specific BART emission
limits and compliance schedules for each source subject to BART. Once a
State has made its BART determination, the BART controls must be
installed and in operation as expeditiously as practicable, but no
later than five years after the date of EPA approval of the regional
haze SIP, as required by CAA (section 169(g)(4)) and the RHR (40 CFR
51.308(e)(1)(iv)). In addition to what is required by the RHR, general
SIP

requirements mandate that the SIP must also include all regulatory
requirements related to monitoring, recordkeeping, and reporting for
the BART controls on the source. States have the flexibility to choose
the type of control measures they will use to meet the requirements of
BART.
    States may also provide an Alternative to BART demonstration. On
October, 13, 2006, EPA finalized ``Regional Haze Regulations; Revisions
to Provisions Governing Alternative to Source-Specific Best Available
Retrofit Technology (BART) Determinations'' (71 FR 60612), an
alternative emissions program that gives flexibility for states or
tribal governments in ways to apply BART. The BART requirements would
be satisfied if the alternative program meets or exceeds the visibility
benefits resulting from BART. This approach has been approved by the
D.C. Circuit. See Center for Energy & Economic Development v. EPA, 398
F.3d 653 (D.C. Cir. 2005); Utility Air Regulatory Group v. EPA, 471
F.3d 1333 (D.C. Cir. 2006).

E. Long-Term Strategy (LTS)

    In 40 CFR 51.308(d)(3) of the RHR, States are required to include a
LTS in their SIPs. The LTS is the compilation of all control measures a
State will use to meet any applicable RPGs. The LTS must include
``enforceable emissions limitations, compliance schedules, and other
measures as necessary to achieve the reasonable progress goals'' for
all Class I areas within, or affected by emissions from, the State. See
40 CFR 51.308(d)(3).
    When a State's emissions are reasonably anticipated to cause or
contribute to visibility impairment in a Class I area located in
another State, the RHR requires the impacted State to coordinate with
the contributing States in order to develop coordinated emissions
management strategies. See 40 CFR 51.308(d)(3)(i). In such cases, the
contributing State must demonstrate that it has included in its SIP all
measures necessary to obtain its share of the emission reductions
needed to meet the RPGs for the Class I area. The RPOs have provided
forums for significant interstate consultation, but additional
consultations between States may be required to sufficiently address
interstate visibility issues. This is especially true where two States
belong to different RPOs.
    States should consider all types of anthropogenic sources of
visibility impairment in developing their LTS, including stationary,
minor, mobile, and area sources. At a minimum, States must describe how
each of the seven factors listed below is taken into account in
developing their LTS: (1) Emission reductions due to ongoing air
pollution control programs, including measures to address RAVI; (2)
measures to mitigate the impacts of construction activities; (3)
emissions limitations and schedules for compliance to achieve the RPG;
(4) source retirement and replacement schedules; (5) smoke management
techniques for agricultural and forestry management purposes including
plans as currently exist within the State for these purposes; (6)
enforceability of emissions limitations and control measures; (7) the
anticipated net effect on visibility due to projected changes in point,
area, and mobile source emissions over the period addressed by the LTS.
See 40 CFR 51.308(d)(3)(v).

F. Coordinating Regional Haze and Reasonably Attributable Visibility
Impairment (RAVI) LTS

    As part of the RHR, EPA revised 40 CFR 51.306(c) regarding the LTS
for RAVI to require that the RAVI plan must provide for a periodic
review and SIP revision not less frequently than every three years
until the date of submission of the State's first plan addressing
regional haze visibility impairment, which was due December 17, 2007,
in accordance with 40 CFR 51.308(b) and (c). On or before this date,
the State must revise its plan to provide for review and revision of a
coordinated LTS for addressing reasonably attributable and regional
haze visibility impairment, and the State must submit the first such
coordinated LTS with its first regional haze SIP. Future coordinated
LTS's, and periodic progress reports evaluating progress towards RPGs,
must be submitted consistent with the schedule for SIP submission and
periodic progress reports set forth in 40 CFR 51.308(f) and 51.308(g),
respectively. The periodic reviews of a State's LTS must report on both
regional haze and RAVI impairment and must be submitted to EPA as a SIP
revision.

G. Monitoring Strategy and Other Implementation Plan Requirements

    In 40 CFR 51.308(d)(4), the RHR requires a monitoring strategy for
measuring, characterizing, and reporting of regional haze visibility
impairment that is representative of all mandatory Class I Federal
areas within the State. The strategy must be coordinated with the
monitoring strategy required in 40 CFR 51.305 for RAVI. Compliance with
this requirement may be met through participation in the Interagency
Monitoring of Protected Visual Environments (IMPROVE) network. The
monitoring strategy is due with the first regional haze SIP, and it
must be reviewed every five years. The monitoring strategy must also
provide for additional monitoring sites if the IMPROVE network is not
sufficient to determine whether RPGs will be met.
    The SIP must also provide for the following:
     Procedures for using monitoring data and other information
in a State with mandatory Class I areas to determine the contribution
of emissions from within the State to regional haze visibility
impairment at Class I areas both within and outside the State;
     Procedures for using monitoring data and other information
in a State with no mandatory Class I areas to determine the
contribution of emissions from within the State to regional haze
visibility impairment at Class I areas in other States;
     Reporting of all visibility monitoring data to the
Administrator at least annually for each Class I area in the State, and
where possible, in electronic format;
     Developing 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 a baseline year, emissions for the most recent year for
which data are available, and estimates of future projected emissions.
A State must also make a commitment to update the inventory
periodically; and
     Other elements, including reporting, recordkeeping, and
other measures necessary to assess and report on visibility.
    Pursuant to 40 CFR 51.308(f) of the RHR, state control strategies
must cover an initial implementation period extending to the year 2018,
with a comprehensive reassessment and revision of those strategies, as
appropriate, every 10 years thereafter. Periodic SIP revisions must
meet the core requirements of 40 CFR 51.308(d) with the exception of
BART. The BART provisions of 40 CFR 51.308(e), as noted above, apply
only to the first implementation period. Periodic SIP revisions will
assure that the statutory requirement of reasonable progress will
continue to be met.

H. Consultation With States and Federal Land Managers (FLMs)

    The RHR requires that States consult with FLMs before adopting and
submitting their SIPs. See 40 CFR 51.308(i). States must provide FLMs
an opportunity for consultation, in person and at least 60 days prior
to holding any public hearing on the SIP. This

consultation must include the opportunity for the FLMs to discuss their
assessment of impairment of visibility in any Class I area and to offer
recommendations on the development of the RPGs and on the development
and implementation of strategies to address visibility impairment.
Further, a State must include in its SIP a description of how it
addressed any comments provided by the FLMs. Finally, a SIP 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.

III. What is EPA's analysis of Massachusetts' Regional Haze SIP
submittal?

    On December 30, 2011, the Division of Air Quality Control of the
MassDEP submitted revisions to the Massachusetts SIP to address
regional haze as required by 40 CFR 51.308. In addition, on May 2,
2012, MassDEP requested parallel processing of its February 17, 2012
Proposed Revision to Massachusetts Regional Haze SIP. EPA has reviewed
Massachusetts' submittals and is proposing to find that they are
consistent with the requirements of 40 CFR 51.308 as outlined in
Section II. A detailed analysis follows.
    Massachusetts is responsible for developing a regional haze SIP
which addresses Massachusetts' impact on any nearby Class I areas. As
Massachusetts has no Class I areas within its borders, Massachusetts is
not required to address the following Regional Haze SIP elements: (a)
Calculation of baseline and natural visibility conditions; (b)
establishment of reasonable progress goals; (c) monitoring
requirements; and (d) RAVI requirements.

A. Massachusetts' Impact on MANE-VU Class I Areas

    Massachusetts is a member of the MANE-VU RPO. The MANE-VU RPO
contains seven Class I areas in four States: Moosehorn Wilderness Area,
Acadia National Park, and Roosevelt/Campobello International Park in
Maine; Presidential Range/Dry River Wilderness Area and Great Gulf
Wilderness Area in New Hampshire; Brigantine Wilderness Area in New
Jersey; and Lye Brook Wilderness Area in Vermont.
    Through source apportionment modeling, MANE-VU assisted States in
determining their contribution to the visibility impairment of each
Class I area in the MANE-VU region. Massachusetts and the other MANE-VU
States adopted a weight-of-evidence approach which relied on several
independent methods for assessing the contribution of different sources
and geographic source regions to regional haze in the northeastern and
mid-Atlantic portions of the United States. Details about each
technique can be found in the Northeast States for Coordinated Air Use
Management (NESCAUM) document Contributions to Regional Haze in the
Northeast and Mid-Atlantic United States, August 2006 (hereinafter
referred to as the ``Contribution Report'').\4\
---------------------------------------------------------------------------

    \4\ The August 2006 NESCAUM document Contributions to Regional
Haze in the Northeast and Mid-Atlantic United States has been
provided as part of the docket to this proposed rulemaking.
---------------------------------------------------------------------------

    The MANE-VU Class I States determined that any State contributing
at least 2.0% of the total sulfate (the main contributor to visibility
impairment in the Northeast, see Section III.C.3) observed on the 20
percent worst visibility days in 2002 was a contributor to visibility
impairment at the Class I areas. Massachusetts emissions were found to
contribute to the total annual average sulfate at the nearby Class I
areas: Acadia National Park, Maine (10.11% of total sulfate); Moosehorn
Wilderness Area, Maine and Roosevelt Campobello International Park
(6.78% of total sulfate); Great Gulf Wilderness Area and Presidential
Range Dry River, New Hampshire (3.11% of total sulfate); Lye Brook
Wilderness Area (2.45% of total sulfate); and Brigantine Wilderness
Area, New Jersey (2.73% of total sulfate). The impact of sulfate on
visibility is discussed in greater detail below.
    EPA is proposing to find that Massachusetts has adequately
demonstrated that emissions from sources within the State cause or
contribute to visibility impairment in nearby Class I Areas.

B. Best Available Retrofit Technology (BART)

    According to 51.308(e), ``The State must submit an implementation
plan containing emission limitations representing BART and schedules
for compliance with BART for each BART-eligible source that may
reasonably be anticipated to cause or contribute to any impairment of
visibility in any Class I Federal area, unless the State demonstrates
that an emissions trading program or other alternative will achieve
greater reasonable progress toward natural visibility conditions.'' On
October 13, 2006, EPA's ``Regional Haze Regulations; Revisions to
Provisions Governing Alternative to Source-Specific Best Available
Retrofit Technology (BART) Determinations; Final Rule'' (hereinafter
known as the ``Alternative to BART Rule'') was published in the Federal
Register. See 71 FR 60612. Massachusetts chose to demonstrate that
programs already developed by the State provide greater progress in
visibility improvement than source-by-source BART determinations. A
demonstration that the alternative program will achieve greater
reasonable progress than would have resulted from the installation and
operation of BART at all sources subject to BART in the state must be
based on the following:
    (1) A list of all BART-eligible sources within the State.
    (2) A list of all BART-eligible sources and all BART source
categories covered by the alternative program.
    (3) Determination of the BART benchmark. If the alternative program
has been designed to meet a requirement other than BART, as in the case
of Massachusetts, the State may determine the best system of continuous
emission control technology and associated emission reductions for
similar types of sources within a source category based on both source
specific and category-wide information, as appropriate.
    (4) An analysis of the projected emission reductions achieved
through the alternative program.
    (5) A determination based on a clear weight of evidence that the
alternative program achieves greater reasonable progress than would be
achieved through the installation and operation of BART at the covered
sources.
    As allowed by the Regional Haze Rule, Massachusetts opted to pursue
source by source BART determinations for select sources and demonstrate
an Alternative to BART for other sources.
1. Identification of All BART Eligible Sources
    Determining BART-eligible sources is the first step in the BART
process. BART-eligible sources in Massachusetts were identified in
accordance with the methodology in Appendix Y of the Regional Haze
Rule, Guidelines for BART Determinations Under the Regional Haze Rule,
Part II, How to Identify BART-Eligible Sources. See 70 FR 39158. This
guidance consists of the following criteria:
     The unit falls into one of the listed source categories;
     The unit was constructed or reconstructed between 1962 and
1977; and

     The unit has the potential to emit over 250 tons per year
of sulfur dioxide, nitrogen oxides, particulate matter, volatile
organic compounds, or ammonia.
    The BART Guidelines require States to address SO2,
NOX, and particulate matter. States are allowed to use their
best judgment in deciding whether VOC or ammonia emissions from a
source are likely to have an impact on visibility in the area. The
State of Massachusetts addressed SO2, NOX, and
used particulate matter less than 10 microns in diameter
(PM10) as an indicator for particulate matter to identify
BART eligible units, as the BART Guidelines require.
    The identification of BART sources in Massachusetts was undertaken
as part of a multi-State analysis conducted by the NESCAUM. NESCAUM
worked with MassDEP licensing engineers to review all sources and
determine their BART eligibility. MassDEP identified twenty-nine
sources as BART-eligible. The Massachusetts BART eligible sources are
listed in Table 1. Three of the sources are petroleum storage
facilities (Exxon Mobile-Everett, Global Petroleum--Revere, and Gulf
Oil--Chelsea) with VOC emissions.
    Consistent with the BART Guidelines, the State of Massachusetts did
not evaluate emissions of VOCs in BART determinations due to the lack
of impact on visibility in the area due to anthropogenic sources. The
majority of VOC emissions in Massachusetts are biogenic in nature.
Therefore, the ability to further reduce total ambient VOC
concentrations at Class I areas is limited. Point, area, and mobile
sources of VOCs in Massachusetts are already comprehensively controlled
as part of an ozone attainment and maintenance strategy.
    Nor did Massachusetts evaluate ammonia. The overall ammonia
inventory is very uncertain, but the amount of anthropogenic emissions
at sources that were BART-eligible is relatively small, and no
additional sources were identified that had greater than 250 tons per
year ammonia and required a BART analysis.\5\
---------------------------------------------------------------------------

    \5\ Visibility Impact is measured in units of deciviews (dv). A
deciview measures the incremental visibility change discernable by
the human eye. The modeling to determine the visibility impact is
discussed below.

                                 Table 1--BART Eligible Sources in Massachusetts
----------------------------------------------------------------------------------------------------------------
                                                                                Highest 2002
    Source, unit and location              Fuel             BART source        2002  emissions      visibility
                                                              category             (ton/yr)       impact (dv)\5\
----------------------------------------------------------------------------------------------------------------
Boston Generating--New Boston      Distillate Oil.....  18.6 MW, EGU.......  SO2: 1, NOX: 170...            0.04
 Unit 1.
Boston Generating--Mystic Unit 7   Residual Oil.......  574 MW, EGU........  SO2: 3,727, NOX:               1.02
 *.                                                                           805.
Braintree Electric Unit 3........  Distillate Oil       76 MW, EGU.........  SO2: 6 NOX: 97.....            0.03
                                    Natural Gas.
Dominion--Brayton Point Unit 1 *.  Coal...............  243 MW, EGU........  SO2: 9,254 NOX:                3.82
                                                                              2,513.
Dominion--Brayton Point Unit 2 *.  Coal...............  240 MW, EGU........  SO2: 8,853 NOX:                3.67
                                                                              2,270.
Dominion--Brayton Point Unit 3 *.  Coal...............  612 MW, EGU........  SO2: 19,450 NOX:               7.25
                                                                              7,335.
Dominion--Brayton Point Unit 4 *.  Residual Oil         435 MW, EGU........  SO2: 2,037 NOX: 552            0.73
                                    Natural Gas.
Dominion--Salem Harbor Unit 4 *..  Residual Oil.......  433 MW, EGU........  SO2: 2,886 NOX: 787            0.98
Harvard University--Blackstone     Residual Oil         83 MW, EGU.........  SO2: 63 NOX: 41....            0.06
 Unit 11.                           Natural Gas.
Harvard University--Blackstone     Residual Oil         83 MW, EGU.........  SO2: 74 NOX: 46....            0.06
 Unit 12.                           Natural Gas.
Mirant--Canal Station Unit 1.....  Residual Oil.......  560 MW, EGU........  SO2: 13,066 NOX:               4.43
                                                                              3,339.
Mirant--Canal Station Unit 2.....  Residual Oil.......  560 MW, EGU........  SO2: 8,948 NOX:                3.26
                                                                              2,260.
Mirant Kendall LLC Unit 1........  Residual Oil         80 MW, EGU.........  SO2: 18 NOX: 172...            0.06
                                    Natural Gas.
Mirant Kendall LLC Unit 2........  Residual Oil         80 MW, EGU.........  SO2: 36 NOX: 96....            0.04
                                    Natural Gas.
Taunton Municipal Light Plant      Residual Oil.......  28 MW, EGU.........  SO2: 37 NOX: 15....            0.01
 (TMLP)--Cleary Flood Unit 8.
Taunton Municipal Light Plant      Residual Oil.......  90 MW, EGU.........  SO2: 55 NOX: 163...            0.07
 (TMLP)--Cleary Flood Unit 9.
Eastman Gelatin Units 1, 2, 3,     Residual Oil         ICI Boilers........  SO2: 5.2 NOX: 51...            0.03
 and 4.                             Natural Gas.
General Electric Aircraft--Lynn    Natural Gas          ICI Boilers........  SO2: 425 NOX: 213..            0.24
 Unit 3.                            Residual Oil.
Solutia..........................  Natural Gas          ICI Boiler.........  NOX: 16............           0.003
                                    Residual Oil Coal.
Trigen--Kneeland St. Unit 3......  Residual Oil         ICI Boiler.........  SO2: 85 NOX: 396...            0.15
                                    Distillate Oil.
Wheelabrator Saugus Units 1......  Mixed Waste........  Municipal            SO2: 42 NOX: 357...            0.25
                                                         Incinerator.
Wheelabrator Saugus Unit 2.......  Mixed Waste........  Municipal            SO2: 42 NOX: 364...            0.25
                                                         Incinerator.
Exxon Mobil--Everett All                                Petroleum Storage..  N/A.
 Processing Units.
Global Petroleum--Revere All                            Petroleum Storage..  N/A.
 Processing Units.
Gulf Oil--Chelsea All Processing                        Petroleum Storage..  N/A.
 Units.
----------------------------------------------------------------------------------------------------------------
* Located at a facility greater than 750 MW.

2. Cap-Outs
    BART applies to sources with the potential to emit 250 tons or more
per year of any visibility impairing pollutant. (70 FR 39160). BART-
eligible sources that adopt a federally enforceable permit limit to
permanently limit emissions of visibility impairing pollutants to less
than 250 tons per year (tpy) may thereby ``cap-out'' of BART. See 70 FR
39112. One Massachusetts source capped out of BART by taking such
limits, General Electric-Lynn Unit 3. Actual emissions of visibility
impairing pollutants from General Electric-Lynn Unit 3 are less than
the 250 tons per year threshold. Pursuant to the request of the source,
MassDEP has established a federally enforceable permit condition that
limits the potential to emit (PTE) NOX and SO2
emissions from Unit 3 to less than 250 tons per year. This permit has
been submitted as part of the Massachusetts SIP submittal (Appendix
BB). The existing PM10 potential to emit is already below
the 250 tpy threshold. As a result, Massachusetts concluded that this
source is not BART eligible. If in the future, this source requests an
increase in its PTE above the 250 tons per year threshold for a
visibility impairing pollutant, it shall be subject to BART.
3. Identification of Sources Subject to BART
    Massachusetts, working with MANE-VU, found that almost every MANE-
VU state with BART-eligible sources contributes to visibility
impairment at one or more Class I areas to a significant degree (See
the MANE-VU Contribution Report). As a result, Massachusetts found that
all BART eligible sources within Massachusetts are subject to BART.
    According to Section III of the Guidelines, once the state has
compiled its list of BART-eligible sources, it needs to determine
whether to make BART determinations for all of the sources or to
consider exempting some of them from BART because they may not
reasonably be anticipated to cause or contribute to any visibility
impairment in a Class I area.
    Based on the collective importance of BART sources, Massachusetts
decided that no exemptions would be given for sources.\6\
---------------------------------------------------------------------------

    \6\ Massachusetts' decision that all BART eligible sources are
subject to BART should not be misconstrued to mean that all BART-
eligible sources must install controls. For sources subject to a
source-specific BART determination, Massachusetts' approach simply
requires the consideration of each of the five statutory factors
before determining whether or not controls are warranted. For
sources that were not subject to source-specific BART
determinations, Massachusetts' alternative to BART requires greater
overall reductions than would have been achieved by application of
source-specific BART, but may not require all sources to install
additional controls.
---------------------------------------------------------------------------

4. Modeling To Demonstrate Source Visibility Impact
    MANE-VU conducted modeling analyses of BART-eligible sources using
the EPA approved air quality model, California Pollution Model
(CALPUFF), in order to provide a regionally-consistent foundation for
assessing the degree of visibility improvement which could result from
the installation of BART controls.\7\ While this modeling analysis
differed slightly from the guidance, it was intended to provide a
first-order estimate of the maximum visibility benefit that could be
achieved by eliminating all emissions from a BART source, and provides
a useful metric for determining which sources are unlikely to warrant
additional controls to satisfy BART.
---------------------------------------------------------------------------

    \7\ The MANE-VU modeling protocol can be found in the NESCAUM
``BART Resource Guide,'' dated August 23, 2006, (www.nescaum.org/documents/bart-resource-guide/bart-resource-guide-08-23-06-final.pdf/)
---------------------------------------------------------------------------

    The MANE-VU modeling effort analyzed 136 BART-eligible sources in
the MANE-VU region using the CALPUFF modeling platform and two
meteorological data sets: (1) A wind field based on National Weather
Service (NWS) observations; and (2) a wind field based on the
Pennsylvania State University/National Center for Atmospheric Research
Mesoscale Meteorological Model (MM5) version 3.6. Modeling results from
both the NWS and MM5 platforms include each BART eligible unit's
maximum 24-hr, 8th highest 24-hr, and annual average impact at the
Class I area.\8\ These visibility impacts were modeled relative to the
20 percent best, 20 percent worst, and average annual natural
background conditions. In accordance with EPA guidance, which allows
the use of either estimates of the 20 percent best or the annual
average of natural background visibility conditions as the basis for
calculating the deciview difference that individual sources would
contribute for BART modeling purposes, MANE-VU opted to utilize the
more conservative best conditions estimates approach because it is more
protective of visibility.
---------------------------------------------------------------------------

    \8\ The NWS and MM5 platform modeling results can be found in
Appendices R-1 and R-2 of the SIP submittal.
---------------------------------------------------------------------------

    The 2002 baseline modeling provides an estimate of the maximum
improvement in visibility at Class I Areas in the region that could
result from the installation of BART controls (the maximum improvement
is equivalent to a ``zero-out'' of emissions). In virtually all cases,
the installation of BART controls would result in less visibility
improvement than what is represented by a source's 2002 impact, but
this approach does provide a consistent means of identifying those
sources with the greatest contribution to visibility impairment.
    In addition to modeling the maximum potential improvement from
BART, MANE-VU also determined that 98 percent of the cumulative
visibility impact from all MANE-VU BART eligible sources corresponds to
a maximum 24-hr impact of 0.22 dv from the NWS-driven data and 0.29 dv
from the MM5 data. As a result, MANE-VU concluded that, on the average,
a range of 0.2 to 0.3 dv would represent a significant impact at MANE-
VU Class I areas, and sources having less than 0.1 dv impact are
unlikely to warrant additional controls under BART.\9\
---------------------------------------------------------------------------

    \9\ As an additional demonstration that sources whose impacts
were below the 0.1 dv level were too small to warrant BART controls,
the entire MANE-VU population of these units was modeled together to
examine their cumulative impacts at each Class I area. The results
of this modeling demonstrated that the maximum 24-hour impact at any
Class I area of all modeled sources with individual impacts below
0.1 dv was only a 0.35 dv change relative to the estimated best days
natural conditions at Acadia National Park. This value is well below
the 0.5 dv impact used by most RPOs and States for determining
whether a BART-eligible source contributes to visibility impairment.
---------------------------------------------------------------------------

    For Massachusetts, sources with visibility impact of 0.1 dv or less
are: Braintree Electric Unit 3; Harvard University--Blackstone Units 11
and 12; Mirant- Kendall Units 1 and 2; New Boston Unit 1; Eastman
Gelatin Units 1, 2, 3, and 4; Solutia; and Trigen--Kneeland Unit 3.\10\
Massachusetts determined that the cost of installing additional
controls on these de minimis units was not cost effective given the
minimal expected visibility impact. Massachusetts therefore determined
that current controls represent BART for these units.
---------------------------------------------------------------------------

    \10\ Trigen-Kneeland has been added to this list, despite its
modeled impact of 0.146 dv (0.127 dv from NO3) using the
MM5 modeling platform, due to two significant errors in the 2002
input data used by MANE-VU to screen facilities for their impact on
visibility. First, Units 1-4 were included in the modeling when only
Unit 3 is BART-eligible. Second, the 2002 modeled NOX
emissions from Unit 3 were 396 tons, rather than the actual 96 tons
of NOX emissions. Massachusetts believes that the
modeling using the corrected 2002 NOX emissions from
Trigen-Kneeland would indicate a total visibility impact of <0.1 dv,
therefore a source with a de minimis impact on visibility.
---------------------------------------------------------------------------

5. Source Specific BART Determination
    The Regional Haze Rule allows Massachusetts to either make
individual BART determinations or to implement

an alternative that will achieve greater reasonable progress toward
natural visibility conditions. Massachusetts developed an individual
BART determination for Wheelabrator--Saugus Units 1 and 2.
a. Background
    Wheelabrator-Saugus is a municipal waste combustor which contains
two mass burn incinerators with water wall boilers, each rated at 325
MMBtu/hr heat input. Both incinerator units are BART-eligible, with
reported combined 2002 emissions of 84 tons of SO2 and 721
tons of NOX.
b. NOX BART Review
    Wheelabrator has NOX control for both units that
includes low-NOX burners and Selective Non-Catalytic
Reduction (SNCR). The current NOX emission limit is 205 ppm
(by volume at 7 percent oxygen dry basis, 24-hour arithmetic average).
MassDEP believes that the low-NOX burners and SNCR are the
most stringent control available for municipal waste combustors. At
MassDEP's request, the facility performed furnace gas temperature
profiling and conducted SNCR optimization testing to determine the
capability to further reduce NOX emission while minimizing
ammonia slip. The optimization test results indicated that a reduced
NOX emission target of 185 ppm (dry, 7% O2) could
be achieved with the existing SNCR system. Therefore Massachusetts
determined that the NOX emission rate of 185 ppm (30-day
average) for each of Wheelabrator's units represents BART.
c. SO2 BART Review
    Wheelabrator's existing control technology for SO2
emissions includes a spray dry absorber (SDA) with lime slurry
injection. Wheelabrator's permitted SO2 emission limit is 29
ppm (by volume at 7 percent oxygen dry basis, 24-hour geometric mean).
CALPUFF modeling suggests that visibility impacts from 2002
SO2 emissions from Wheelabrator--Saugus are below 0.1 dv on
the worst day at any Class I area. Massachusetts determined that
further controls for SO2 are not warranted given the minimal
potential visibility improvement and that current controls are
equivalent to federal Maximum Achievable Control Technology (MACT)
standards (40 CFR Part 60 Subpart Cb).
d. PM BART Review
    Each of Wheelabrator's units is equipped with 10-module fabric
filters (baghouses) and is subject to a PM emission limit 27 mg/dscm or
less at 7 percent oxygen (dry basis). On March 14, 2012, MassDEP issued
an ECP Modified Final Approval for Wheelabrator that reduced its PM
emission limit to 25 mg/dscm or less at 7 percent oxygen (dry basis).
Massachusetts determined that additional PM controls were not warranted
given the additional cost of installation and the already strict
controls in place at Wheelabrator.
e. EPA Assessment
    EPA has reviewed the Massachusetts analysis and concluded it was
conducted in a manner consistent with EPA's BART Guidelines. The
proposed NOX, PM, and SO2 limits meet the current
federal Maximum Achievable Control Technology (MACT) limits. See 40 CFR
Part 60 Subpart Cb (71 FR 27324, May 10, 2006). The BART Rule states,
``Unless there are new technologies subsequent to the MACT standards
which would lead to cost-effective increases in the level of control,
you may rely on the MACT standards for purposes of BART.'' (50 FR
39164, (July 6, 2005)). The MACT standard for Large Municipal Waste
Combustors was modified in 2006, with the standards taking effect in
2009. We are currently unaware of any new technology available that
would require reevaluation of the cost-effectiveness of additional
controls. EPA is proposing to find that the Massachusetts analysis and
conclusions for the BART emission units located at Wheelabrator--Saugus
are reasonable.
6. Identification of All BART Source Categories Covered by the
Alternative Program
    To address the BART requirement for the remaining sources subject
to BART, Massachusetts opted to implement an ``Alternative to BART''
measure.
    In crafting Massachusetts' Alternative to BART demonstration, the
State relied on: SO2 and NOX emission reductions
required by 310 CMR 7.29, ``Emissions Standards for Power Plants;'' the
retirement of Somerset Power; permit restrictions for Brayton Point,
Salem Harbor, and Mount Tom Station that limits SO2 and/or
NOX emissions; 310 CMR 7.19, ``Reasonably Available Control
Technology for sources of Oxides of Nitrogen NOX;'' and
MassDEP's proposed amendments to its low sulfur fuel oil regulation,
which requires EGU's that burn residual oil to limit the sulfur content
of 0.5% by weight beginning July 1, 2014.
    The Massachusetts Alternative to BART includes emission reductions
from all of the remaining BART-eligible EGUs, as well as, select EGUs
determined to be too old to meet the definition of BART-eligible.
7. Determination of the BART Benchmark
    In developing the BART benchmark,\11\ with one exception, States
must follow the approach for making source-specific BART determinations
under section 51.308(e)(1). The one exception to this general approach
is where the alternative program has been designed to meet requirements
other than BART, such as being part of the State's long term strategy
to meet reasonable progress goals. In this case, States are not
required to conduct a full BART analysis under 51.308(e)(1) for each
source and may instead use simplifying assumptions in establishing a
BART benchmark based on an analysis of what BART is likely to be for
similar types of sources within a source category using category-wide
or source-specific information as appropriate. Under either approach to
establishing a BART benchmark, we believe that the presumptions for
EGUs in the BART Guidelines should be used for comparison to a trading
or other alternative program, unless the State determines that such
presumptions are not appropriate for a particular EGU. See 71 FR 60619.
Massachusetts' program is part of the State's long term strategy and
even though Massachusetts had the option of using the less stringent
EPA presumptive limits, the State opted to use the MANE-VU recommended
BART emission limits for non-CAIR EGUs in setting the BART benchmark.
These limits are listed in Table 2.
---------------------------------------------------------------------------

    \11\ The BART benchmark is intended to provide a target emission
reduction--what would the expected reductions in emissions have been
if the State had chosen to apply source-specific BART to all of its
BART sources--for comparison to the Alternative to BART.

                Table 2--MANE-VU Recommended BART Limits
------------------------------------------------------------------------
          Category                 SO2 Limits            NOX Limits
------------------------------------------------------------------------
Non-CAIR EGUs...............  Coal--95% control or  In NOX SIP call
                               0.15 lb/MMBtu.        area, extend use of
                                                     controls to year
                                                     round.
                              Oil--95% control or   0.1-0.25 lb/MMBtu
                               0.33 lb/MMBtu (0.3%   depending on coal
                               fuel sulfur limit).   and boiler type.
------------------------------------------------------------------------

8. Massachusetts' SO2 Alternative BART Program
    The Massachusetts Alternative to BART is comprised of:
     310 CMR 7.29, ``Emission Standards for Power Plants,''
which establishes SO2 emission standards for certain EGUs.
     Permit restrictions for Mount Tom Station, Brayton Point
Station, and Salem Harbor that disallow the use of 310 CMR 7.29
SO2 Early Reduction Credits and federal Acid Rain Allowances
for compliance with 310 CMR 7.29.
     An annual cap of 300 tons of SO2 for Salem
Harbor Unit 2, and a shutdown of Units 3 and 4 beginning June 1, 2014.
     The retirement of Somerset Power in 2010.
     MassDEP's proposed low sulfur fuel oil regulation, which
would require EGUs that burn residual oil to limit the sulfur content
to 0.5% by weight beginning July 1, 2014.
    Massachusetts included previously adopted 310 CMR 7.29, ``Emission
Standards for Power Plants,'' as part of its February 17, 2012 proposed
Regional Haze SIP supplement. 310 CMR 7.29 was adopted in 2001 as a
means to reduce NOX, SO2, mercury (Hg), and
carbon dioxide (CO2) emissions from the State's largest
fossil fueled EGUs. The rule established a two-phased schedule. The
second phase became effective October 1, 2006. The Massachusetts
Emission Standards for power plants establishes a facility-wide rolling
12-month SO2 emission rate of 3.0 pounds per megawatt-hour
and a monthly average emission rate of 6.0 pounds per megawatt-hour.
This regulation allows the use of SO2 Early Reduction
Credits (on a 1 ton credit to 1 ton excess emission basis) and the use
of federal Acid Rain SO2 Allowances (on a 3 ton allowance to
1 ton excess emission basis) for compliance with the 3.0 pound per
mega-watt hour emission rate. 310 CMR 7.29 applies to Brayton Point
(Units 1, 2, 3, 4), Canal Station (Units 1 and 2), Mount Tom Station
(Unit 1), Mystic Station (Units 4, 5, 6, 7, 81, 82, 93, and 94), Salem
Harbor Station (Units 1, 2, 3, and 4), and NRG Somerset (Unit 8).
    On May 15, 2009, MassDEP issued an amended Emission Control Plan
Final Approval \12\ for Mount Tom that prohibits the use of Early
Reduction Credits (ERCs) and federal Acid Rain Allowances for
compliance with 310 CMR 7.29 after June 1, 2014. In a similar fashion,
on February 16, 2012, at Brayton Point's request, MassDEP issued an
Amended Emission Control Plan Draft Approval \13\ which prohibits the
use of ERCs and federal Acid Rain Allowances for compliance with 310
CMR 7.29 after June 1, 2014.
---------------------------------------------------------------------------

    \12\ The Mount Tom amended Emission Control Plan can be found in
Appendix EE of the February 17, 2012 Proposed Revision to
Massachusetts Regional Haze State Implementation Plan.
    \13\ The Brayton Point amended Emission Control Plan can be
found in Appendix GG of the February 17, 2012 Proposed Revision to
Massachusetts Regional Haze State Implementation Plan.
---------------------------------------------------------------------------

    On February 17, 2012, at Salem Harbor's request, MassDEP proposed
an Amended Emission Control Plan \14\ that prohibits the use of ERCs
and federal Acid Rain Allowances for compliance with 310 CMR 7.29,
after June 1, 2014. The emission control plan also establishes an
annual cap of 300 tons of SO2 for Salem Harbor 2 and the
shutdown of Units 3 and 4 effective June 1, 2014. Per a consent
decree,\15\ Salem Harbor Units 1 and 2 were removed from service as of
December 31, 2011, which means that these units can no longer generate
electricity for the power grid. However, under the consent decree these
units were not restricted from operating for other purposes. The
consent decree therefore does not act as a federally enforceable limit
on emissions from these units. MassDEP's proposed permit restrictions
will make the emission reductions from Salem Harbor federally
enforceable. As such these reductions are not required under the
consent decree and are included in Massachusetts' Alternative to BART.
---------------------------------------------------------------------------

    \14\ The Salem Harbor amended Emission Control Plan can be found
in Appendix FF of the February 17, 2012 Proposed Revision to
Massachusetts Regional Haze State Implementation Plan.
    \15\ Conservation Law Foundation v. Dominion Energy New England,
Inc., Case No. 1:10-cv-11069 (D. Mass. 2012), http://www.clf.org/wp-content/uploads/2012/02/Signed-Consent-Decree-12_11.pdf.
---------------------------------------------------------------------------

    Instead of complying with 310 CMR 7.29, Somerset Power ceased
operating in 2010, and on June 22, 2011, at Somerset Power's request,
MassDEP issued a letter that revoked all air approvals and permits for
the facility and deemed all pending permit applications withdrawn.\16\
---------------------------------------------------------------------------

    \16\ Appendix HH of the Massachusetts February 17, 2012 SIP
submittal.
---------------------------------------------------------------------------

    The final component of the Massachusetts Alternative to BART is the
MassDEP proposed amendment to 310 CMR 7.05, ``Fuels All Districts,'' to
lower the allowable sulfur content of distillate oil and residual oil
combusted by stationary sources. For residual oil, 310 CMR 7.05
currently includes a range of sulfate content limits, from 0.5% to
2.2%, depending on the area of the state. The proposed amendment would
establish a 0.5% sulfur content limit for power plants as of July 1,
2014.
Analysis of Alternative to BART for SO2
    Table 3 shows the BART benchmark projected SO2 emissions
for the BART-eligible units included in the alternative program. The
emissions were calculated by multiplying the MANE-VU BART workgroup
recommended BART SO2 emission rate in lb/MMBtu (see Table 2
above) by each unit's 2002 baseline heat input in MMBtu. Massachusetts
determined that the BART benchmark emission reduction is 50,752 tons of
SO2 (68,328 tons minus 17,576 tons).

                                         Table 3--BART Benchmark for SO2
----------------------------------------------------------------------------------------------------------------
                                                                                MANE-VU
                                                     2002 SO2                       recommended   Estimated  SO2
         BART eligible facility            Unit      emissions       2002 Heat       SO2 BART        emissions
                                                      (tons)      input  (MMBtu)   emission rate      (tons)
                                                                                (lbs/MMBtu)
----------------------------------------------------------------------------------------------------------------
Brayton Point..........................        1           9,254      17,000,579            0.15           1,275
Brayton Point..........................        2           8,853      15,896,795            0.15           1,192
Brayton Point..........................        3          19,450      36,339,809            0.15           2,725
Brayton Point..........................        4           2,037       4,787,978            0.33             790
Canal Station..........................        1          13,066      27,295,648            0.33           4,504
Canal Station..........................        2           8,948      19,440,919            0.33           3,208
Cleary Flood...........................        8              39          92,567            0.33              15
Cleary Flood...........................        9              68       2,123,819            0.33             350
Mystic.................................        7           3,727      15,172,657            0.33           2,503
Salem Harbor...........................        4           2,886       6,137,412            0.33           1,013
                                        ------------------------------------------------------------------------
     Total.............................  .......          68,328  ..............  ..............          17,576
----------------------------------------------------------------------------------------------------------------

    Table 4 shows the Alternative to BART estimated SO2
emissions, which MassDEP calculated by multiplying the proposed low-
sulfur fuel oil regulation SO2 emission rates in lbs/MMBtu
by the 2002 heat input in MMBtu, or by multiplying the 310 CMR 7.29
SO2 rolling 12-month emission rate in lbs/MWh by the 2002
megawatt-hours electrical generation, and accounting for permit
restrictions in effect at Mount Tom Station and proposed for Brayton
Point and Salem Harbor, as well as the retirement of Somerset Power.
MassDEP calculated that the Alternative to BART results in an estimated
emission reduction of 54,986 tons from 2002 emissions (89,254 tons
minus 34,268). This reduction is 4,234 tons (54,986 tons minus 50,752
tons) more than the calculated emission reduction from the BART
benchmark. Massachusetts determined that its proposed Alternative to
BART for SO2 would therefore result in more emissions
reductions than would have been achieved through the application of
source-specific BART.

                                      Table 4--Alternative to BART for SO2
----------------------------------------------------------------------------------------------------------------
                                             2002 SO2       2002 Heat input    Alternative BART   Estimated  SO2
            Facility               Unit      emissions        (MMBtu) or      emission rate (lbs/    emissions
                                              (tons)       generation (MWh)    MMBtu or lbs/MWh)      (tons)
----------------------------------------------------------------------------------------------------------------
Brayton Point..................        1           9,254  1,951,839 MWh.....  3.0 lbs/MWh.......           2,928
Brayton Point..................        2           8,853  1,855,515 MWh.....  3.0 lbs/MWh.......           2,783
Brayton Point..................        3          19,450  4,294,957 MWh.....  3.0 lbs/MWh.......           6,442
Brayton Point..................        4           2,037  4,787,978 MMBtu...  0.56 lbs/MMBtu....           1,341
Canal Station..................        1          13,066  27,295,648 MMBtu..  0.56 lbs/MMBtu....           7,643
Canal Station..................        2           8,948  19,440,919 MMBtu..  0.56 lbs/MMBtu....           5,443
Cleary Flood...................        8              39  92,567 MMBtu......  0.56 lbs/MMBtu....              25
Cleary Flood...................        9              68  2,123,819 MMBtu...  0.56 lbs/MMBtu....             595
Mount Tom......................        1           5,282  1,047,524 MWh.....  3.0 lbs/MWh.......           1,571
Mystic.........................        7           3,727  15,172,657 MMBtu..  0.56 lbs/MMBtu....           4,248
Salem Harbor...................        1           3,425  631,606 MWh.......  3.0 lbs/MWh.......             947
Salem Harbor...................        2           2,821  527,939 MWh.......  Cap...............             300
Salem Harbor...................        3           4,999  974,990 MWh.......  Retired...........               0
Salem Harbor...................        4           2,886  6,137,412 MMBtu...  Retired...........               0
Somerset.......................        8           4,399  8,910,087 MMBtu...  Retired...........               0
                                --------------------------------------------------------------------------------
     Total.....................  .......          89,254  ..................  ..................          34,268
----------------------------------------------------------------------------------------------------------------

    Section 40 CFR 51.308(e)(3) provides a process for determining
whether an alternative measure makes greater reasonable progress than
would be achieved through the installation and operation of BART. If
the geographic distribution of emission reductions is similar between
an alternative measure and BART, the comparison of the two measures may
be made on the basis of emissions alone. The alternative measure may be
deemed to make greater progress than BART if it results in greater
emission reductions than requiring sources subject to BART to install,
operate, and maintain BART. In this case, the Alternative to BART
achieves greater emission reductions than BART. Aside from Mount Tom,
all of the Alternative to BART sources are coastally located EGUs in
Eastern Massachusetts--two of which, Brayton Point and Somerset, are
located in the same municipality. Massachusetts concluded that the
geographic distribution of emission reductions is not significantly
different than the application of source specific BART. Therefore,
Massachusetts determined that its Alternative to BART for
SO2 would result in greater reasonable progress than
application of source-specific BART.
9. Massachusetts' NOX Alternative BART Program
    The Massachusetts Alternative to BART for NOX relies on:
     310 CMR 7.29, ``Emissions Standards for Power Plants,''
which establishes NOX emissions limits for certain EGUs.

     An annual cap of 276 tons of NOX for Salem
Harbor Unit 1 and an annual cap of 50 tons of NOX for Unit
2, and a shutdown of Units 3 and 4 beginning June 1, 2014.
     The retirement of Somerset Power in 2010.
     310 CMR 7.19, ``Reasonably Available Control Technology
(RACT) for Sources of Oxides of Nitrogen NOX,'' which
establishes NOX emission standards for various sources,
including EGUs.
    MassDEP's existing regulation 310 CMR 7.29, ``Emission Standards
for Power Plants'' establishes a rolling 12-month average
NOX emission rate of 1.5 lbs/MWh and a monthly average
emission rate of 3 lbs/MWh. 310 CMR 7.29 applies to Brayton Point
(Units 1, 2, 3, 4), Canal Station (Units 1 and 2), Mount Tom Station
(Unit 1), Mystic Station (Units 4, 5, 6, 7, 81, 82, 93, and 94), Salem
Harbor Station (Units 1, 2, 3, and 4), and NRG Somerset (Unit 8).
    On February 17, 2012, at Salem Harbor's request, MassDEP proposed
an Amended ECP Approval \17\ that requires an annual cap of 276 tons of
NOX for Salem Harbor Unit 1 and an annual cap of 50 tons of
NOX for Unit 2, and a shutdown of Units 3 and 4 beginning
June 1, 2014. While these units are subject to a consent decree that
requires them to be removed from electric generation service, the
consent decree does not prevent these units from operation other than
electric generation service. Therefore, Massachusetts' proposed Amended
ECP Approval will result in an enforceable limitation on emissions from
Salem Harbor in excess of currently required reductions.
---------------------------------------------------------------------------

    \17\ The Salem Harbor amended Emission Control Plan can be found
in Appendix FF of the February 17, 2012 Proposed Revision to
Massachusetts Regional Haze State Implementation Plan.
---------------------------------------------------------------------------

    Somerset Power ceased operating in 2010, and on June 22, 2011, at
Somerset's Power's request, MassDEP issued a letter \18\ that revoked
all air approvals and permits for the facility and deemed all pending
permit applications withdrawn.
---------------------------------------------------------------------------

    \18\ Appendix HH of the Massachusetts February 17, 2012 SIP
submittal.
---------------------------------------------------------------------------

    MassDEP's existing regulation 310 CMR 7.19 establishes
NOX emission rates for various stationary sources, including
EGUs. Under 310 CMR 7.19, Cleary Flood Units 8 and 9 are subject to a
NOX emission rate of 0.28 lbs/MMBtu. Mystic Unit 7 is
subject to a NOX emission rate of 0.25 lb/MMBtu. Mystic is
also subject to 310 CMR 7.29 on a facility-wide basis. However, Mystic
Unit 7 could exceed the 310 CMR 7.29 NOX rate of 1.5 lbs/MWh
while the facility as a whole complies with the rate because the other
units at Mystic are natural gas-fired with low NOX
emissions, and therefore the 310 CMR 7.19 unit-specific NOX
rate of 0.25 lbs/MMBtu is the controlling factor for Unit 7.
Analysis of the Alternative BART Program for NOX
    Table 5 shows the BART benchmark NOX emissions for the
BART-eligible units, which were calculated by multiplying the lowest,
more stringent MANE-VU BART workgroup recommended emission rate of 0.1
lb/MMBtu by the 2002 heat input in MMBtu. The BART benchmark results in
a calculated emission reduction of 12,820 tons of NOX
(20,034 tons minus 7,214 tons) from 2002 emissions.

                                         Table 5--BART Benchmark for NOX
----------------------------------------------------------------------------------------------------------------
                                                                                MANE-VU
                                                     2002 NOX                       recommended    Estimated NOX
         BART-eligible facility            Unit      emissions       2002 Heat       BART NOX        emissions
                                                      (tons)      input  (MMBtu)   emission rate      (tons)
                                                                                (lbs/MMBtu)
----------------------------------------------------------------------------------------------------------------
Brayton Point..........................        1           2,513      17,000,579            0.10             850
Brayton Point..........................        2           2,270      15,896,795            0.10             795
Brayton Point..........................        3           7,335      36,339,809            0.10           1,817
Brayton Point..........................        4             552       4,787,978            0.10             239
Canal Station..........................        1           3,339      27,295,648            0.10           1,365
Canal Station..........................        2           2,260      19,440,919            0.10             972
Cleary Flood...........................        8              12          92,567            0.10               5
Cleary Flood...........................        9             161       2,123,819            0.10             106
Mystic.................................        7             805      15,172,657            0.10             759
Salem Harbor...........................        4             787       6,137,412            0.10             307
                                        ------------------------------------------------------------------------
     Total.............................  .......          20,034  ..............  ..............           7,214
----------------------------------------------------------------------------------------------------------------

    Table 6 shows the Alternative to BART NOX emissions,
which were calculated by multiplying MassDEP's 310 CMR 7.29
NOX emission rate in lb/MWh and 310 CMR 7.19 NOX
emission rate in lb/MMBtu by the 2002 electricity generation in MWh and
2002 heat input in MMBtu respectively, and accounting for permit
restrictions proposed for Salem Harbor and the retirement of Somerset
Power. The Alternative to BART results in an emission reduction of
13,116 tons (26,455 tons minus 13,339 tons) from 2002 emissions. The
estimated NOX reductions from the Alternative to BART are
296 tons (13,116 tons minus 12,820 tons) more than estimated reductions
from BART alone. Massachusetts determined that its proposed Alternative
to BART for NOX would therefore result in more emissions
reductions than would have been achieved through the application of
source-specific BART.

                                      Table 6--Alternative to BART for NOX
----------------------------------------------------------------------------------------------------------------
                                             2002 NOX       2002 heat input    Alternative BART    Estimated NOX
            Facility               Unit      emission         (MMBtu) or      emission rate (lbs/    emissions
                                              (tons)       generation (MWh)    MMBtu or lbs/MWh)      (tons)
----------------------------------------------------------------------------------------------------------------
Brayton Point..................        1           2,513  1,951,839 MWh.....  1.5 lbs/MWh.......           1,464
Brayton Point..................        2           2,270  1,855,515 MWh.....  1.5 lbs/MWh.......           1,392

Brayton Point..................        3           7,335  4,294,957 MWh.....  1.5 lbs/MWh.......           3,221
Brayton Point..................        4             552  401,305 MWh.......  1.5 lbs/MWh.......             301
Canal Station..................        1           3,339  2,945,578 MWh.....  1.5 lbs/MWh.......           2,209
Canal Station..................        2           2,260  1,910,079 MWh.....  1.5 lbs/MWh.......           1,433
Cleary Flood...................        8              12  92,567 MMBtu......  0.28 lbs/MMBtu....              13
Cleary Flood...................        9             161  2,123,819 MMBtu...  0.28 lbs/MMBtu....             297
Mount Tom......................        1           1,969  1,047,524 MWh.....  1.5 lbs/MWh.......             786
Mystic.........................        7             805  15,172,657 MMBtu..  0.25 lbs/MMBtu....           1,897
Salem Harbor...................        1             920  631,606 MWh.......  Cap...............             276
Salem Harbor...................        2             755  527,939 MWh.......  Cap...............              50
Salem Harbor...................        3           1,331  974,990 MWh.......  Retired...........               0
Salem Harbor...................        4             787  508,342 MWh.......  Retired...........               0
Somerset.......................        8           1,445  8,910,087 MMBtu...  Retired...........               0
                                --------------------------------------------------------------------------------
    Total......................  .......          26,455  ..................  ..................          13,339
----------------------------------------------------------------------------------------------------------------

    As with SO2, the Alternative to BART achieves greater
NOX emission reductions than source by source BART.
Massachusetts determined that the geographic distribution of the
emission reductions is not significantly different than the application
of source specific BART. Therefore, Massachusetts determined that its
Alternative to BART would result in greater reasonable progress than
application of source-specific BART.
10. EPA's Assessment of Massachusetts' Alternative to BART
Demonstration
    EPA is proposing to find that Massachusetts has demonstrated that
the Alternative to BART achieves greater SO2 and
NOX emission reductions than expected from source by source
BART. EPA is also proposing to find that the geographic distribution of
the emission reductions from the Alternative to BART is not
significantly different to the geographic distribution expected from
source by source BART emission reductions, therefore visibility
modeling is not required, as noted in the Alternative to BART Rule. See
71 FR 60612.\19\ Thus, EPA is proposing to find that the SO2
and NOX Alternative to BART measures meet the requirements
of the Alternative to BART Rule.
---------------------------------------------------------------------------

    \19\ In addition, because the SO2 and NOX
Alternatives to BART do not involve emissions trading between
sources, review under EPA's Guidance on Economic Incentive Programs
(EIPs) is not required. Improving Air Quality with Economic
Incentive Programs (2001), http://www.epa.gov/ttncaaa1/t1/memoranda/eipfin.pdf.
---------------------------------------------------------------------------

11. Massachusetts' PM BART Determinations
    Massachusetts' proposed Alternative to BART does not cover
PM10 emissions. An overview of 2002 and 2009 PM10
emissions and PM controls at the EGU BART sources is contained in Table
7. Collectively, these facilities emitted 1,531 tons of PM10
in 2002 that diminished visibility in the New England Class I areas by
0.032-0.037 deciviews. Through installation of controls for other
purposes, these facilities have significantly reduced PM emissions, so
that in 2009 these facilities emitted a total of 109 tons of
PM10.

                                            Table 7--Massachusetts PM10 BART Sources, Emissions, and Controls
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                PM emission
                                                                           2002 PM10       2009 PM10                                       limits  lbs/
                    Source                       Unit      PM10  dv        emissions       emissions               PM controls              MMBtu as of
                                                                             (tpy)           (tpy)                                             2009
--------------------------------------------------------------------------------------------------------------------------------------------------------
Brayton Point................................        1    0.031, 0.026             386              39  Fabric Filter Baghouse..........            0.08
Brayton Point................................        2  ..............  ..............  ..............  Fabric Filter Baghouse..........            0.08
Brayton Point................................        3  ..............  ..............  ..............  Fabric Filter Baghouse (Planned)            0.08
Brayton Point................................        4    0.000, 0.000               6               0  ESP.............................            0.03
Canal Station................................        1    0.000, 0.000             672              60  ESP.............................            0.02
Canal Station................................        2  ..............  ..............  ..............  ESP.............................            0.02
Mystic Station...............................        7    0.002, 0.003             131               4  ESP.............................            0.05
Salem Harbor.................................        4    0.001, 0.001             316               0  ESP.............................            0.04
Cleary Flood.................................        8    0.003, 0.002              20               6   None...........................            0.12
Cleary Flood.................................        9  ..............  ..............  ..............   None...........................            0.12
--------------------------------------------------------------------------------------------------------------------------------------------------------

    CALPUFF modeling of the 2002 PM emissions at these facilities shows
an impact that was well below the 0.1 dv on the worst day at affected
Class I areas, for each unit and cumulatively, which is the level MANE-
VU has identified that the degree of visibility improvement is so small
(<0.1 dv) that no reasonable weighting of factors could justify
additional controls under BART. The visibility would be even lower
today based on the emission reductions achieved since 2002.
Massachusetts therefore determined that no additional controls are
warranted for primary PM10.

EPA's Assessment
    EPA is proposing to approve Massachusetts' determination that
further primary PM control beyond the controls already implemented by
Massachusetts' BART-eligible units is not warranted at this time as
such measures are not cost-effective and the visibility contribution
from Massachusetts' BART-eligible units with respect to PM is
insignificant.
12. BART Enforceability
    The BART emission limits referenced above are enforceable through a
variety of mechanisms. Specifically, MassDEP's 310 CMR 7.19,
``Reasonably Available Control Technology (RACT) of Sources of Oxides
of Nitrogen (NOX),'' which establishes NOX
emission rates for various stationary sources, including EGUs, was
previously approved into the Massachusetts SIP on December 27, 2000.
See 65 FR 81743. The PM limits for Brayton Point (Units 1, 2 3, and 4),
Canal Station (Units 1 and 2), Mystic Station (Unit 7), and Salem
Harbor (Unit 4) are enforceable by permit conditions issued under
Massachusetts' federally approved permit process. In addition, the PM
limits for Cleary Flood (Units 8 and 9) are enforceable via 310 CMR
7.02, ``Plans and Approvals and Emission Limitations,'' which was
previously approved into the Massachusetts SIP on October 28, 1972. See
37 FR 23085. Finally, a number of requirements were included in the
MassDEP February 17, 2012 proposal.
    Pursuant to MassDEP's request for parallel processing of the
proposed SIP revision, EPA is proposing approval of Massachusetts'
Final ECP Approval--Wheelabrator Saugus, Amended ECP for Brayton Point,
Amended ECP for Salem Harbor Station, Amended ECP for Mount Tom
Station, Amended ECP for Somerset Station, and previously adopted 310
CMR 7.29, ``Emission Standards for Power Plants,'' and proposed
Amendments to 310 CMR 7.05, ``Fuels all Districts'' and 310 CMR 7.00,
``Definitions.'' After the State submits the final version of the
February 17, 2012 proposed SIP revision (including a response to all
public comments raised during the State's public participation
process), EPA will prepare a final rulemaking notice. If the State's
formal SIP submittal contains changes which occur after EPA's notice of
proposed rulemaking, such changes must be described in EPA's final
rulemaking action. If the State's changes are significant, then EPA
must decide whether to finalize approval with a description of the
changes, re-propose our action with regard to the State's SIP
submittal, or take other action as may be appropriate.

C. Long-Term Strategy

    As described in Section II.E of this action, the LTS is a
compilation of State-specific control measures relied on by the State
to obtain its share of emission reductions to support the RPGs
established by Maine, New Hampshire, Vermont, and New Jersey, the
nearby Class I area States. Massachusetts' LTS for the first
implementation period addresses the emissions reductions from federal,
State, and local controls that take effect in the State from the
baseline period starting in 2002 until 2018. Massachusetts participated
in the MANE-VU regional strategy development process and supported a
regional approach towards deciding which control measures to pursue for
regional haze, which was based on technical analyses documented in the
following reports:
    (a) The Contribution Report; (b) Assessment of Reasonable Progress
for Regional Haze in MANE-VU Class I Areas (available at
www.marama.org/visibility/RPG/FinalReport/RPGFinalReport_070907.pdf);
(c) Five-Factor Analysis of BART-Eligible Sources: Survey of Options
for Conducting BART Determinations (available at www.nescaum.org/documents/bart-final-memo-06-28-07.pdf); and (d) Assessment of Control
Technology Options for BART-Eligible Sources: Steam Electric Boilers,
Industrial Boilers, Cement Plants and Paper, and Pulp Facilities
(available at www.nescaum.org/documents/bart-control-assessment.pdf).
1. Emissions Inventory for 2018 With Federal and State Control
Requirements
    The State-wide emissions inventories used by MANE-VU in its
regional haze technical analyses were developed by MARAMA for MANE-VU
with assistance from Massachusetts. The 2018 emissions inventory was
developed by projecting 2002 emissions forward based on assumptions
regarding emissions growth due to projected increases in economic
activity and emissions reductions expected from federal and State
regulations. MANE-VU's emissions inventories included estimates of
NOX, PM10, PM2.5, SO2, VOC,
and NH3. The BART guidelines direct States to exercise
judgment in deciding whether VOC and NH3 impair visibility
in their Class I area(s). As discussed further in Section III.C.3
below, MANE-VU demonstrated that anthropogenic emissions of sulfates
are the major contributor to PM2.5 mass and visibility
impairment at Class I areas in the Northeast and Mid-Atlantic region.
It was also determined that the total ammonia emissions in the MANE-VU
region are extremely small.
    MANE-VU developed emissions inventories for four inventory source
classifications: (1) Stationary point sources, (2) stationary area
sources, (3) non-road mobile sources, and (4) on-road mobile sources.
The New York Department of Environmental Conservation also developed an
inventory of biogenic emissions for the entire MANE-VU region.
Stationary point sources are those sources that emit greater than a
specified tonnage per year, depending on the pollutant, with data
provided at the facility level. Stationary area sources are those
sources whose individual emissions are relatively small, but due to the
large number of these sources, the collective emissions from the source
category could be significant. Non-road mobile sources are equipment
that can move but do not use the roadways. On-road mobile source
emissions are automobiles, trucks, and motorcycles that use the roadway
system. The emissions from these sources are estimated by vehicle type
and road type. Biogenic sources are natural sources like trees, crops,
grasses, and natural decay of plants. Stationary point sources emission
data is tracked at the facility level. For all other source types,
emissions are summed on the county level.
    There are many federal and State control programs being implemented
that MANE-VU and Massachusetts anticipate will reduce emissions between
the baseline period and 2018. Emission reductions from these control
programs in the MANE-VU region were projected to achieve substantial
visibility improvement by 2018 at all of the MANE-VU Class I areas. To
assess emissions reductions from ongoing air pollution control
programs, BART, and reasonable progress goals, MANE-VU developed 2018
emissions projections called ``Best and Final.'' The emissions
inventory provided by the Commonwealth of Massachusetts for the Best
and Final 2018 projections is based on expected control requirements.
    Massachusetts relied on emission reductions from the following
ongoing and expected air pollution control programs as part of the
State's long term strategy. For electrical generating units (EGUs),
Massachusetts relied on 310 CMR 7.29, ``Emissions Standards for Power
Plants'' which limits SO2 and NOX emissions from
the six largest fossil fuel-fired power plants in Massachusetts.
Massachusetts also

relied on the following controls on non-EGU point sources in estimating
2018 emissions inventories: NOX SIP Call Phases I and II;
NOX Reasonably Available Control Technology (RACT) in 1-hour
Ozone SIP; VOC 2-year, 4-year, 7-year and 10-year Maximum Achievable
Control Technology (MACT) Standards; Combustion Turbine and
Reciprocating Internal Combustion Engine (RICE) MACT; and Industrial
Boiler/Process Heater MACT (also known as the Industrial Boiler MACT).
    On July 30, 2007, the U.S. Court of Appeals for the District of
Columbia vacated and remanded the Industrial Boiler MACT Rule. NRDC v.
EPA, 489F.3d 1250 (D.C. Cir. 2007). This MACT was vacated since it was
directly affected by the vacatur and remand of the Commercial and
Industrial Solid Waste Incinerator (CISWI) definition rule. EPA
proposed a new Industrial Boiler MACT rule to address the vacatur on
June 4, 2010 (75 FR 32006) and issued a final rule on March 21, 2011
(76 FR 15608). On May 18, 2011, EPA stayed the effective date of the
Industrial Boiler MACT pending review by the D.C. Circuit or the
completion of EPA's reconsideration of the rule. See 76 FR 28662.
    On December 2, 2011, EPA issued a proposed reconsideration of the
MACT standards for existing and new boilers at major (76 FR 80598) and
area (76 FR 80532) source facilities, and for Commercial and Industrial
Solid Waste Incinerators (76 FR 80452). On January 9, 2012, the U.S.
District Court for the District of Columbia vacated EPA's stay of the
effectiveness date of the Industrial Boiler MACT, reinstating the
original effective date and therefore requiring compliance with the
current rule in 2014. Sierra Club v. Jackson, Civ. No. 11-1278, slip
op. (D.D.C. Jan. 9, 2012).
    Even though Massachusetts' modeling is based on the old Industrial
Boiler MACT limits, Massachusetts' modeling conclusions are unlikely to
be affected because the expected reductions in SO2 and PM
resulting from the vacated MACT rule are a relatively small component
of the Massachusetts inventory and the expected emission reductions
from the final MACT rule are comparable to those modeled. In addition,
the new MACT rule requires compliance by 2014 and therefore the
expected emission reductions will be achieved prior to the end of the
first implementation period in 2018. Thus, EPA does not expect that
differences between the old and revised Industrial Boiler MACT emission
limits would affect the adequacy of the existing Massachusetts regional
haze SIP. If there is a need to address discrepancies between projected
emissions reductions from the old Industrial Boiler MACT and the
Industrial Boiler MACT finalized in March 2011, we expect Massachusetts
to do so in its 5-year progress report.
    Controls on area sources expected by 2018 include: VOC rules for
consumer products (310 CMR 7.25(12)); VOC control measures for
architectural and industrial maintenance coatings (310 CMR 7.25(11))
and solvent cleaning (310 CMR 7.18(8)); VOC control measures for
cutback asphalt paving (310 CMR 7.18(9)); and VOC control measures for
portable fuel containers (contained in EPA's Mobile Source Air Toxics
rule).
    Controls on mobile sources expected by 2018 include: enhanced
inspection and maintenance (I/M) inspection for 1984 and new vehicles
(310 CMR 60.02); Federal On-Board Refueling Vapor Recovery (ORVR) Rule;
Federal Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur
Requirements; Federal Heavy-Duty Diesel Engine Emission Standards for
Trucks and Buses; and Federal Emission Standards for Large Industrial
Spark-Ignition Engines and Recreation Vehicles.
    Controls on non-road sources expected by 2018 include the following
federal regulations: Control of Air Pollution: Determination of
Significance for Nonroad Sources and Emission Standards for New Nonroad
Compression Ignition Engines at or above 37 kilowatts (59 FR 31306,
June 17, 1994); Control of Emissions of Air Pollution from Nonroad
Diesel Engines (63 FR 56967, Oct. 23, 1998); Control of Emissions from
Nonroad Large Spark-Ignition Engines and Recreational Engines (67 FR
68241, Nov. 8, 2002); and Control of Emissions of Air Pollution from
Nonroad Diesel Engines and Fuels (69 FR 38958, June 29, 2004).
    Tables 8 and 9 are summaries of the 2002 baseline and 2018
estimated emissions inventories for Massachusetts. The 2018 estimated
emissions include emissions growth as well as emission reductions due
to ongoing emission control strategies and reasonable progress goals.

                                               Table 8--2002 Emission Inventory Summary for Massachusetts
                                                                     [Tons per year]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                        Category                                VOC             NOX            PM2.5           PM10             NH3             SO2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................           5,647          45,590           4,161           5,852           1,526         101,049
Area....................................................         159,753          34,371          43,203         191,369          16,786          25,585
On-Road Mobile..........................................          57,186         143,368           2,410           3,408           5,499           4,399
Non-Road Mobile.........................................          56,749          42,769           3,226           3,531              28           3,791
Biogenics...............................................         113,957           1,257  ..............  ..............  ..............  ..............
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................         393,292         267,355          53,000         204,160          23,839         134,824
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                               Table 9--2018 Emission Inventory Summary for Massachusetts
                                                                     [Tons per year]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                        Category                                VOC             NOX            PM2.5           PM10             NH3             SO2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Point...................................................          10,902          40,458           6,827           9,137           1,622          55,878
Area....................................................         134,963          36,199          31,237          82,027          19,552           1,804
On-Road Mobile..........................................          17,056          22,813             840             893           5,817           1,937
Non-Road Mobile.........................................          36,306          27,040           2,052           2,246              36             442
Biogenics...............................................         113,958           1,257  ..............  ..............  ..............  ..............
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................         313,185         127,767          40,956          94,303          27,027          60,061
--------------------------------------------------------------------------------------------------------------------------------------------------------

2. Modeling To Support the LTS
    MANE-VU performed modeling for the regional haze LTS for the 11
Mid-Atlantic and Northeast States and the District of Columbia. The
modeling analysis is a complex technical evaluation that began with
selection of the modeling system. MANE-VU used the following modeling
system:
     Meteorological Model: The Fifth-Generation Pennsylvania
State University/National Center for Atmospheric Research (NCAR)
Mesoscale Meteorological Model (MM5) version 3.6 is a nonhydrostatic,
prognostic meteorological model routinely used for urban- and regional-
scale photochemical, PM2.5, and regional haze regulatory
modeling studies.
     Emissions Model: The Sparse Matrix Operator Kernel
Emissions (SMOKE) version 2.1 modeling system is an emissions modeling
system that generates hourly gridded speciated emission inputs of
mobile, non-road mobile, area, point, fire, and biogenic emission
sources for photochemical grid models.
     Air Quality Model: The EPA's Models-3/Community Multiscale
Air Quality (CMAQ) version 4.5.1 is a photochemical grid model capable
of addressing ozone, PM, visibility and acid deposition at a regional
scale.
     Air Quality Model: The Regional Model for Aerosols and
Deposition (REMSAD), is a Eulerian grid model that was primarily used
to determine the attribution of sulfate species in the Eastern U.S. via
the species-tagging scheme.
     Air Quality Model: The California Puff Model (CALPUFF),
version 5 is a non-steady-state Lagrangian puff model used to access
the contribution of individual States' emissions to sulfate levels at
selected Class I receptor sites.
    CMAQ modeling of regional haze in the MANE-VU region for 2002 and
2018 was carried out on a grid of 12x12 kilometer (km) cells that
covers the 11 MANE-VU States (Connecticut, Delaware, Maine, Maryland,
Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode
Island, and Vermont) and the District of Columbia and States adjacent
to them. This grid is nested within a larger national CMAQ modeling
grid of 36x36 km grid cells that covers the continental United States,
portions of Canada and Mexico, and portions of the Atlantic and Pacific
Oceans along the east and west coasts. Selection of a representative
period of meteorology is crucial for evaluating baseline air quality
conditions and projecting future changes in air quality due to changes
in emissions of visibility-impairing pollutants. MANE-VU conducted an
in-depth analysis which resulted in the selection of the entire year of
2002 (January 1-December 31) as the best period of meteorology
available for conducting the CMAQ modeling. The MANE-VU States'
modeling was developed consistent with EPA's Guidance on the Use of
Models and Other Analyses for Demonstrating Attainment of Air Quality
Goals for Ozone, PM2.5, and Regional Haze, April 2007 (EPA-454/B-07-
002, available at www.epa.gov/scram001/guidance/guide/final-03-pm-rh-guidance.pdf), and EPA document, Emissions Inventory Guidance for
Implementation of Ozone and Particulate Matter National Ambient Air
Quality Standards (NAAQS) and Regional Haze Regulations, August 2005
and updated November 2005 (EPA-454/R-05-001, available at www.epa.gov/ttnchie1/eidocs/eiguid/index.html) (hereinafter referred to as ``EPA's
Modeling Guidance'').
    MANE-VU examined the model performance of the regional modeling for
the areas of interest before determining whether the CMAQ model results
were suitable for use in the regional haze assessment of the LTS and
for use in the modeling assessment. The modeling assessment predicts
future levels of emissions and visibility impairment used to support
the LTS and to compare predicted, modeled visibility levels with those
on the uniform rate of progress. In keeping with the objective of the
CMAQ modeling platform, the air quality model performance was evaluated
using graphical and statistical assessments based on measured ozone,
fine particles, and acid deposition from various monitoring networks
and databases for the 2002 base year. MANE-VU used a diverse set of
statistical parameters from the EPA's Modeling Guidance to stress and
examine the model and modeling inputs. Once MANE-VU determined the
model performance to be acceptable, MANE-VU used the model to assess
the 2018 RPGs using the current and future year air quality modeling
predictions, and compared the RPGs to the uniform rate of progress.
    In accordance with 40 CFR 51.308(d)(3), the Commonwealth of
Massachusetts provided the appropriate supporting documentation for all
required analyses used to determine the State's LTS. The technical
analyses and modeling used to support the LTS are consistent with EPA's
RHR, and interim and final EPA Modeling Guidance. EPA is proposing to
find the MANE-VU technical modeling to support the LTS is acceptable
because the modeling system was chosen and used according to EPA
Modeling Guidance. EPA agrees with the MANE-VU model performance
procedures and results, and that CMAQ, REMSAD, and CALPUFF are
appropriate tools for the regional haze assessments for the
Massachusetts LTS and regional haze SIP.
3. Relative Contributions of Pollutants to Visibility Impairment
    An important step toward identifying reasonable progress measures
is to identify the key pollutants contributing to visibility impairment
at each Class I area. To understand the relative benefit of further
reducing emissions from different pollutants, MANE-VU developed
emission sensitivity model runs using CMAQ to evaluate visibility and
air quality impacts from various groups of emissions and pollutant
scenarios in the Class I areas on the 20 percent worst visibility days.
    Regarding which pollutants are most significantly impacting
visibility in the MANE-VU region, MANE-VU's contribution assessment
demonstrated that sulfate is the major contributor to PM2.5
mass and visibility impairment at Class I areas in the Northeast and
Mid-Atlantic Region. Sulfate particles commonly account for more than
50 percent of particle-related light extinction at northeastern Class I
areas on the clearest days and for as much as, or more than, 80 percent
on the haziest days. For example, at the Brigantine National Wildlife
Refuge Class I area (the MANE-VU Class I area with the greatest
visibility impairment), on the 20 percent worst visibility days in
2000-2004, sulfate accounted for 66 percent of the particle extinction.
After sulfate, organic carbon (OC) consistently accounts for the next
largest fraction of light extinction. Organic carbon accounted for 13
percent of light extinction on the 20 percent worst visibility days for
Brigantine, followed by nitrate that accounts for 9 percent of light
extinction. On the best visibility days, sulfate accounts for 50
percent of the particle related visibility extinction. Organic carbon
accounts for the next largest contribution of 40 percent of the
visibility impairment on the clearest days. Nitrate, elemental carbon,
and fine soil typically contribute less than 10 percent of the
visibility impairment mass on the clearest days.
    The emissions sensitivity analyses conducted by MANE-VU predict
that reductions in SO2 emissions from EGU and non-EGU
industrial point sources will result in the greatest improvements in
visibility in the Class I areas in the

MANE-VU region, more than any other visibility-impairing pollutant. As
a result of the dominant role of sulfate in the formation of regional
haze in the Northeast and Mid-Atlantic Region, MANE-VU concluded that
an effective emissions management approach would rely heavily on broad-
based regional SO2 control efforts in the eastern United
States.
4. Meeting the MANE-VU ``Ask''
    Since the Commonwealth of Massachusetts does not have a Class I
area, it is not required to establish RPGs. However, as a MANE-VU
member State, Massachusetts adopted the ``Statement of MANE-VU
Concerning a Request for a Course of Action by States Within MANE-VU
Toward Assuring Reasonable Progress'' on June 7, 2007. This document
included four emission management strategies that will provide for
reasonable progress towards achieving natural visibility at the MANE-VU
Class I areas. These emission management strategies are collectively
known as the MANE-VU ``Ask,'' and include: (a) Timely implementation of
BART requirements; (b) a 90 percent reduction in SO2
emissions from each of the EGU stacks identified by MANE-VU comprising
a total of 167 stacks; \20\ (c) adoption of a low sulfur fuel oil
strategy; and (d) continued evaluation of other control measures to
reduce SO2 and NOX emissions.
---------------------------------------------------------------------------

    \20\ See Appendix E--``Top Electrical Generating Unit List'' of
the Massachusetts SIP submittal for a complete listing of the 167
stacks.
---------------------------------------------------------------------------

a. Timely Implementation of BART
    Massachusetts will be controlling its BART sources through the
application of source-specific BART or its Alternative to BART. The
source-specific BART determinations and the Alternative to BART are
discussed in detail in Section III.B. Massachusetts has requested
parallel processing of its February 17, 2012 proposal to make several
of the emission reductions expected from the Alternative to BART
federally enforceable.
b. Ninety Percent Reduction in SO2 Emissions From Each of
the EGU Stacks Identified by MANE-VU Comprising a Total of 167 Stacks
    Massachusetts is home to five sources with a total of 10 of the 167
EGU stacks which have been identified by MANE-VU as top contributors to
visibility impairment in any of the MANE-VU Class I areas. These
sources are Brayton Point (Units 1-3), Canal Station (Units 1-2), Mount
Tom Station (Unit 1), Salem Harbor (Units 1, 3, and 4), and Somerset
Power (Unit 8). Each of these facilities is subject to MassDEP's 310
CMR 7.29, which limits SO2 emissions facility-wide.
    Several of the Massachusetts EGUs already have installed
SO2 controls or are planning additional SO2
controls to help them meet 310 CMR 7.29 limits. Brayton Point has
installed spray dryer absorbers on Units 1 and 2 and plans to operate a
dry scrubber on Unit 3 starting in 2012. Mount Tom Station has
installed a dry scrubber. Salem Harbor plans to shut down all units by
2014. Somerset Power shut down in 2010. Canal Station is using lower
sulfur oil to comply with 310 CMR 7.29, and will be subject to
MassDEP's proposed low sulfur oil regulation.
    Table 10 shows that SO2 emissions were reduced by 72%
from 2002 to 2011 at the targeted units. Additional reductions will
occur in the 2012-2014 timeframe as the Salem Harbor units retire and
the Brayton Unit 3 scrubber becomes operational.

                                                          Table 10--Massachusetts Targeted EGUs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                2018 Projected  2018 Projected  2018 Projected
                            Facility                               Unit      2002 SO2        2011 SO2      SO2 emissions   SO2 emissions   SO2 emissions
                                                                             emissions       emissions    (conservative)     (likely)      (90% target)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Brayton Point..................................................        1           9,254           4,298           2,928           1,700             925
Brayton Point..................................................        2           8,853           3,535           2,783           1,590             885
Brayton Point..................................................        3          19,450          10,769           6,442           3,634           1,945
Canal Station..................................................        1          13,066              99           7,643           1,069           1,307
Canal Station..................................................        2           8,948              29           5,443           1,479             895
Mt Tom.........................................................        1           5,282             129           1,571           1,033             528
Salem Harbor...................................................        1           3,425             893               0               0             343
Salem Harbor...................................................        3           4,999           2,344               0               0             500
Salem Harbor...................................................        4           2,886              69               0               0             289
Somerset.......................................................        8           4,399               0               0               0             440
                                                                ----------------------------------------------------------------------------------------
    Total......................................................  .......          80,562          22,165          26,811          10,505           8,057
--------------------------------------------------------------------------------------------------------------------------------------------------------
Reduction......................................................  .......  ..............          59,396          53,751          70,057          72,505
Percent Reduction..............................................  .......  ..............             72%             67%             87%             90%