[Federal Register Volume 76, Number 215 (Monday, November 7, 2011)]
[Rules and Regulations]
[Pages 69052-69077]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-28816]



[[Page 69051]]

Vol. 76

Monday,

No. 215

November 7, 2011

Part VII





Environmental Protection Agency





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





40 CFR Part 52





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





Final Response to Petition From New Jersey Regarding SO2 
Emissions From the Portland Generating Station; Final Rule

  Federal Register / Vol. 76, No. 215 / Monday, November 7, 2011 / 
Rules and Regulations  

[[Page 69052]]


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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR PART 52

[EPA-HQ-OAR-2011-0081; FRL-9487-8]
RIN 2060-AQ69


Final Response to Petition From New Jersey Regarding 
SO2 Emissions From the Portland Generating Station

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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

SUMMARY: The EPA is making a finding that the coal-fired Portland 
Generating Station (Portland), owned and operated by GenOn REMA LLC 
(GenOn), in Upper Mount Bethel Township, Northampton County, 
Pennsylvania, is emitting air pollutants in violation of the interstate 
transport provisions of the Clean Air Act (CAA or Act). Specifically, 
the EPA finds that emissions of sulfur dioxide (SO2) from 
Portland significantly contribute to nonattainment and interfere with 
maintenance of the 1-hour SO2 national ambient air quality 
standard (NAAQS) in New Jersey. This finding is made in response to a 
petition submitted by the State of New Jersey Department of 
Environmental Protection (NJDEP) on September 17, 2010. In this action, 
the EPA is establishing emission limitations and compliance schedules 
to ensure that Portland will eliminate its significant contribution to 
nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey. Compliance with these limits will 
permit the continued operation of Portland beyond the 3-month limit 
established by the CAA for sources subject to a contribution finding.

DATES: This final rule is effective on January 6, 2012.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-HQ-OAR-2011-0081. All documents in the docket are 
listed on the http://www.regulations.gov Web site. Although listed in 
the index, some information is not publicly available, e.g., 
confidential business information (CBI) or other information whose 
disclosure is restricted by statute. Certain other material, such as 
copyrighted material, will be publicly available only in hard copy 
form. Publicly available docket materials are available either 
electronically through http://www.regulations.gov or in hard copy at 
the Air and Radiation Docket and Information Center, EPA/DC, EPA West 
Building, Room 3334, 1301 Constitution Ave. NW., Washington, DC. The 
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the Public 
Reading Room is (202) 566-1744, and the telephone number for the Air 
Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: Mr. Todd Hawes (919) 541-5591, 
[email protected], or Ms. Gobeail McKinley (919) 541-5246, 
[email protected], Office of Air Quality Planning and Standards, 
Air Quality Policy Division, Mail Code C539-04, Research Triangle Park, 
NC 27711.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Executive Summary
II. Summary of Changes From the April 7, 2011 Proposed Rule
III. The Basis for Making the Section 126 Finding for Portland
    A. CAA Section 126(b) and Our Legal Authority
    B. Summary of Comments and Responses Regarding Legal Authority
IV. Summary and Assessment of the Modeling and Other Data Relevant 
to the EPA's Proposed Finding
    A. Summary of the Modeling for the Proposed Rule
    1. Modeling Analysis in NJDEP's Section 126 Petition
    a. Model Selection
    b. Meteorological Data
    2. The EPA's Modeling Analysis To Quantify Significant 
Contribution
    B. Public Comments Related to the Modeling
    1. Model Selection
    2. Meteorological Data
    3. Emissions and Source Characteristics
    4. Identification of Background Concentrations
    5. Columbia Monitor Data and Analyses
    C. Modeling and Other Analyses To Determine Significant 
Contribution for the Final Rule
V. Establishing the Emission Limits Necessary for the Remedy
    A. Quantification of Necessary Emission Reductions
    B. Summary of the EPA's Proposed Remedy Analysis
    C. Summary of Comments and Responses Regarding the Remedy 
Modeling
    D. The Final Remedy Limit
    E. Compliance Schedule for the Final Remedy Limit
    1. Proposed Compliance Schedule
    2. Public Comments and the EPA's Responses
    a. Technical Feasibility
    b. Continued Operation of Facility in the Interim Period
    c. Harmonization With Other Requirements
    3. The Final Rule
    F. Other Considerations for Establishing the Final Remedy
    1. Economic Feasibility
    2. Requirement for Continuous Monitoring
    3. Delegation of Enforcement
VI. Increments of Progress
    A. Interim Emission Limits
    1. What the EPA Proposed
    2. Public Comments and the EPA's Responses
    a. Appropriateness of Including Interim Emissions Limits
    b. Technical Feasibility of Coal Switching
    c. Interim Limits Suggested by the GenOn Test Burn Report
    d. Load Shifting
    e. One-Year Time Period
    f. Effect of Interim Limits on Reliability
    g. Clear Rational for Limits
    h. Combined Emission Limits
    3. Final Rule Interim Emission Limits
    B. Increments of Progress: Reporting Milestones
    1. What the EPA Proposed
    2. Public Comments and the EPA's Responses
    3. Final Rule Reporting Milestones
VII. Alternate Compliance Schedule and Consideration of Petition for 
Rulemaking for Alternative Emission Limits
    A. Alternate Compliance Schedule if the Source Owner Opts To 
Cease Operations
    1. What the EPA Proposed
    2. Public Comments and the EPA's Responses
    3. The Final Rule
    B. Consideration of Petition for Rulemaking for Alternative 
Emission Limits
VIII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act of 1995
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
    J. National Technology Transfer and Advancement Act
    K. Congressional Review Act
    L. Judicial Review

I. Executive Summary

    Section 126(b) of the CAA provides, among other things, that any 
state or political subdivision may petition the Administrator of the 
EPA to find that any major source or group of stationary sources in 
upwind states emits or would emit any air pollutant in violation of the 
prohibition of section110(a)(2)(D)(i),\1\ 42

[[Page 69053]]

U.S.C. 7426(b). On September 17, 2010, NJDEP filed a section 126 
petition requesting that the EPA find that emissions from Portland, 
located in Upper Mount Bethel Township, Northampton County, 
Pennsylvania, significantly contribute to nonattainment or interfere 
with maintenance of the 1-hour SO2 NAAQS in New Jersey. In 
this action, the EPA is granting that petition, and basing its finding 
on the review of NJDEP's air quality modeling, the EPA's independent 
assessment of the AERMOD \2\ dispersion modeling, and other technical 
analyses. Based on this assessment, the EPA finds that Portland's 
emissions significantly contribute to nonattainment and interfere with 
maintenance of the 1-hour SO2 NAAQS in New Jersey. Pursuant 
to section 126(c), the EPA is also authorizing continued operation of 
the plant consistent with emission limitations and compliance schedules 
(including increments of progress) set forth in this rule to bring the 
plant into compliance as expeditiously as practicable with the CAA 
prohibition on emissions that significantly contribute to nonattainment 
and interfere with maintenance of the 1-hour SO2 NAAQS. 
Specifically, the final rule requires Portland to reduce its 
SO2 emissions to meet the following limits: 1,105 pounds per 
hour (lb/hr) for unit 1; 1,691 lb/hr for unit 2; and 0.67 pounds per 
million metric British units (lb/mmBtu), based on a 30 boiler operating 
day rolling average, for units 1 and 2. Portland must achieve and 
maintain these emission limitations by no later than 3 years after the 
effective date of this rule. The EPA is establishing an interim 
SO2 emission limit requirement to ensure that Portland 
demonstrates appropriate increments of progress toward final 
compliance. Specifically, no later than 1 year after the effective date 
of this rule, total SO2 emissions from units 1 and 2 
combined may not exceed 6,253 lb/hr. The final rule also requires 
Portland to submit to the EPA a dispersion modeling protocol within six 
months of the effective date of the rule, a modeling analysis 
demonstrating the elimination of significant contribution to 
nonattainment and interference with maintenance within 1 year of the 
effective date of the rule, semi-annual interim progress reports, and a 
final progress report to demonstrate compliance with the interim and 
final emission limits. Compliance with the final emission limits 
established in this rule is sufficient to remedy Portland's significant 
contribution to nonattainment and interference with maintenance in the 
impacted areas in New Jersey.
---------------------------------------------------------------------------

    \1\ The text of section 126 codified in the United States Code 
cross references section 110(a)(2)(D)(ii) instead of section 
110(a)(2)(D)(i). The courts have confirmed that this is a 
scrivener's error and the correct cross reference is to section 
110(a)(2)(D)(i), See Appalachian Power Co. v. EPA, 249 F.3d 1032, 
1040-44 (DC Cir. 2001).
    \2\ AERMOD stands for the American Meteorological Society/
Environmental Protection Agency Regulatory Model.
---------------------------------------------------------------------------

II. Summary of Changes From the April 7, 2011 Proposed Rule

    The following is a summary of the significant changes made since 
proposal. Each of these changes is discussed later in this notice, and, 
where noted, additional information is provided in other supporting 
documentation in the docket for this rulemaking. The first change is 
that the final compliance remedy now includes a heat input-based 
SO2 emission limit of 0.67 lb/mmBtu for units 1 and 2, in 
addition to the proposed SO2 emission rate limits. The heat-
input based SO2 emission limit is based on a 30 boiler 
operating day rolling average. This additional requirement was made to 
address concerns raised by commenters that the proposed compliance 
remedy was not adequate to ensure attainment of the NAAQS in New 
Jersey. This issue is discussed in more detail in section V.
    Second, the interim emission rate limits, proposed as 2,910 lb/hr 
for unit 1 and 4,450 lb/hr for unit 2, and having a compliance date of 
no later than 1 year from the effective date of this rule, are now 
expressed as a single limit for units 1 and 2 combined, and may not 
exceed 6,253 lb/hr. The 1-year compliance timeframe remains unchanged. 
This change to the limit is partly in response to comments (including 
those from GenOn) in support of greater operational flexibility, and 
acknowledges that the interim limit need not be unit specific. It is 
also based on the availability of lower sulfur coal than the coal 
Portland is currently using. Additional details are provided in section 
VI.C.
    Third, in response to comments that the proposed deadlines for 
submitting a modeling protocol and modeling analysis were too short, 
the deadline for submitting the modeling protocol is changed to six 
months after the effective date of this rule, and the requirement to 
submit a modeling analysis is changed to 12 months after the effective 
date of this rule. This will allow Portland more time for planning its 
modeling analysis but does not change the compliance time frames for 
meeting the emission limits.
    Additionally, in response to comments suggesting the plant needed 
more than 90 days to determine a method of compliance, the final rule 
gives Portland 12 months from the effective date to indicate how it 
intends to achieve full compliance. The EPA agrees that the plant may 
need 12 months to identify the specific engineering and technology 
decisions to determine how to reach compliance within 3 years. 
Accordingly, we are eliminating the proposed requirement for Portland 
to notify the EPA, within 90 days from the effective date of this rule, 
whether the plant will continue to operate and comply with the emission 
limits and compliance schedules, or cease operations. The modeling 
protocol and the initial semi-annual progress report, due 6 months 
after the effective date of this rule, will appropriately inform 
Portland's plans for continuing operation. Finally, the EPA is not 
requiring separate compliance schedules and analyses should Portland 
decide to permanently cease operation of unit 1 and unit 2 as a means 
of compliance. The final and interim emission limits and compliance 
schedules are appropriate regardless of how Portland ultimately decides 
to meet them. Thus, we decided it was not necessary, as proposed, to 
include a separate schedule specifically for a compliance approach 
based on shutting down.

III. The EPA's Basis for Making the Section 126 Finding for Portland

A. CAA Section 126(b) and Our Legal Authority

    The statutory authority for this action is provided by the CAA, as 
amended, 42 U.S.C. 7401 et seq. Section 126 of the CAA provides that 
any state or political subdivision may petition the Administrator of 
the EPA to find that any major source or group of stationary sources in 
upwind states emits or would emit any air pollutant in violation of the 
prohibition of section 110(a)(2)(D)(i). 42 U.S.C. 7426(b). If the EPA 
makes such a finding, in order to allow continued operation of the 
source, the EPA may also issue emission limits and compliance schedules 
(including increments of progress) to bring the source into compliance 
as expeditiously as practicable but no later than 3 years from the date 
of the finding. Absent such emission limits and a compliance schedule, 
the source may not continue operations beyond 90 days.
    Section 110(a)(2)(D) of the CAA, often referred to as the ``good 
neighbor'' or ``interstate transport'' provision of the Act, addresses 
interstate transport of air pollution. Under section 110(a)(2)(D)(i), 
emissions in one state that contribute significantly to nonattainment 
in, or interfere with maintenance of a NAAQS

[[Page 69054]]

by, any other state, or interfere with measures required to be included 
in the applicable implementation plan for any other state under part C 
to prevent significant deterioration of air quality or to protect 
visibility, are to be prohibited. 42 U.S.C. 7410(a)(2)(D)(i). Findings 
by the Administrator, made pursuant to section 126, that a source or 
group of sources emits air pollutants in violation of the section 
110(a)(2)(D)(i) prohibition are commonly referred to as section 126 
findings. Similarly, petitions submitted pursuant to this section are 
commonly referred to as section 126 petitions. This action responds to 
a section 126 petition submitted by the NJDEP. In this action, the EPA 
makes a section 126 finding with respect to Portland and establishes 
emission limits and compliance schedules to permit continued operation 
of the plant.
    Several commenters asserted that the EPA cannot, or should not, 
make such a section 126 finding at this time, but can only make such a 
finding after the state has submitted what is usually referred to as 
its ``interstate transport'' or section 110(a)(2)(D) State 
Implementation Plan (SIP). For the recently promulgated 1-hour 
SO2 standard, those SIPs are due on June 3, 2013. We 
disagree with this interpretation of the Act. The plain language of the 
statute confirms that section 126 remedies can, and in some cases must, 
be promulgated prior to the deadline for states to make SIP submissions 
under section 110(a)(2)(D).
    The EPA has consistently interpreted the language in section 126 as 
referring to a functional prohibition on emissions. This interpretation 
is supported by the plain language of the statute, the statutory 
structure, and the legislative history. Further, the EPA notes that the 
statute does not exempt, for any period of time, violations of the 
prohibition from scrutiny under section 126. For these reasons, the EPA 
believes its interpretation is compelled by the statutory language. 
Nonetheless, to the extent that the statutory language is ambiguous, 
the EPA's reasonable interpretation of this language is to be accorded 
deference.
    The EPA interprets the language in section 126 as referring to the 
actual functional prohibition of section 110(a)(2)(D)(i) that bars 
impermissible interstate transport. The EPA does not agree with the 
position taken by some commenters that the language refers only to an 
emissions limitation contained in a state's section 110(a)(2)(D) SIP. 
Further, there is nothing in the statute to support the argument that 
the prohibition on emissions does not arise until after the SIP 
submission deadline, or that a violation of the functional prohibition 
cannot occur before that deadline. Where the EPA finds such a violation 
exists, it must, under section 126, issue emission limits and 
compliance schedules to permit continued operation of the source.
    The EPA's interpretation of section 126 acknowledges that Congress 
created two independent statutory tools--section 110(a)(2)(D)(i) and 
section 126--to address the problem of interstate pollution transport. 
The purpose of each provision is to control upwind emissions that 
contribute significantly to downwind states' nonattainment or 
maintenance problems. The two provisions differ in that one relies on 
state regulation and the other relies on federal regulation. Congress 
provided both provisions without indicating any preference for one over 
the other, suggesting it viewed either approach as a legitimate means 
to produce the desired result. Instead, the statutory language creates 
two independent tools to address the problem. Section 110(a)(2)(D)(i) 
establishes an obligation for all states to address emissions within 
the state significantly contributing to downwind air quality problems 
or interfering with certain regulatory provisions in downwind states. 
Section 126 establishes a procedure for a state, or political 
subdivision, to petition the EPA to take federal action to address 
transported emissions from an identified source or group of sources in 
another state. The two provisions are independent, and nothing in the 
statute suggests that one is intended to limit the other.
    In general, statutes are to be interpreted in a way that gives 
meaning to each section. The EPA's interpretation of section 126 is 
consistent with this general rule in that it gives section 126 a 
purpose independent of the other remedies available under the CAA. In 
contrast, if section 126 were interpreted as referring only to a 
prohibition contained in a SIP, the section would not have any 
practical utility in the statutory scheme. The EPA's interpretation of 
the relationship between sections 126 and 110 is supported by the 
legislative history of the amendments to the CAA which added section 
126. In adopting the section 126 remedies, Congress explained that the 
petition process was intended to provide an avenue for relief separate 
from the 110(a)(2)(D) SIP procedure and that it was intended to 
expedite, not delay, resolution of interstate pollution conflicts.
    The EPA's interpretation of the ``prohibition'' referred to in 
section 126 is also consistent with the language of section 
110(a)(2)(D)(ii), which requires states to include in their SIPs 
provisions necessary to ensure compliance with sections 126 and 115 of 
the CAA, which relate to interstate transport and international 
transport of pollution, respectively. States are required to submit to 
the EPA such SIPs no later than 3 years after promulgation of a new or 
revised NAAQS. 42 U.S.C. 7410(a)(1). Thus, pursuant to section 
110(a)(2)(D)(ii), any emission limits and compliance schedules issued 
by the Administrator under section 126 prior to that deadline must be 
incorporated into the section 110(a)(2)(D) SIP submission for the state 
in which a source subject to such limits is located. Accordingly, the 
statute anticipates that the Administrator may address a section 126 
petition prior to the deadline for the initial submission of a section 
110(a)(2)(D) SIP.
    If Congress had intended to limit the EPA's authority to act on 
section 126 petitions until after the deadline for states to submit 
110(a)(2)(D) SIPs, it could have included such a restriction. However, 
the plain language of the statute does not clearly require this 
interpretation. Rather, the statute requires the EPA to address a 
section 126 petition within 60 days after receipt.\3\ Since the statute 
establishes firm deadlines for action on section 126 petitions, it does 
not provide an exception for petitions submitted prior to the good 
neighbor SIP submission deadline, and it provides a mechanism for 
incorporating reductions required in response to section 126 petitions 
into the state SIPs; the EPA believes it does not have discretion to 
delay action on a section 126 petition just because the state SIP 
submission deadline has not yet passed.
---------------------------------------------------------------------------

    \3\ This deadline can be extended by up to 6 months pursuant to 
section 307(d)(10).
---------------------------------------------------------------------------

    The EPA's interpretation of sections 110 and 126 in this context is 
also reasonable as it is consistent with the EPA's interpretation of 
these sections in two rulemakings issued in May 1999 and January 2000 
which concluded that each section of the Act provides an alternative 
avenue for relief. Findings of Significant Contribution and Rulemaking 
on Section 126 Petitions for Purposes of Reducing Interstate Ozone 
Transport, 64 FR 28250 (May 25, 1999); Findings of Significant 
Contribution and Rulemaking on Section 126 Petitions for Purposes of 
Reducing Interstate Ozone Transport, 65 FR 2674 (Jan. 18, 2000). NJDEP 
has, in this case, sought relief via section 126 from the interstate 
transport of pollution that is significantly

[[Page 69055]]

contributing to nonattainment within the state, and the EPA is 
obligated to address NJDEP's petition pursuant to the requirements of 
the Act.

B. Summary of Comments and Responses Regarding Legal Authority

    Comment: Several commenters argue that the statutory text is 
unambiguous in requiring that states be permitted to submit their 
infrastructure SIPs addressing the transport requirements of section 
110(a)(2)(D) before a section 126 petition can be filed.
    The commenters primarily argue that this interpretation is 
compelled because a section 126 petition may only be filed to complain 
of a violation of a section 110(a)(2)(D) SIP where a state has failed 
to adequately enforce its own plan. Accordingly, the commenters argue 
that there is no prohibition of transport emissions absent an approved 
SIP. The operative language in section 126 is that a petition may be 
granted where there is ``a violation of the prohibition of'' section 
110(a)(2)(D)(i). The commenters argue that ``prohibition'' referred to 
in section 126 is not on the act of emitting or contributing to 
transboundary nonattainment. Rather, the commenters assert, the 
prohibition is against emitting at levels that violate the limits 
imposed by the SIP regulations promulgated in response to the 
requirements of the CAA.
    Some of these commenters also suggest that a section 126 petition 
would be justified where a state fails to meet its SIP revision 
obligations under section 110(a)(2)(D). These commenters therefore 
argue that a section 126 petition may not be filed until the state 
fails to meet its deadline to file a SIP addressing its transport 
obligations with respect to the new or revised NAAQS.
    Response: The EPA does not agree that the interpretation posited by 
the commenters is reasonable much less compelled by the statutory text. 
Nothing in the statutory language in section 126 prohibits a downwind 
state from filing a section 126 petition until after the upwind state, 
in which the source or sources are located, has submitted, or is 
required to submit, a section 110(a)(2)(D) SIP to the EPA for approval. 
The commenters have not identified any statutory provision that so 
limits a downwind state's rights. Rather, the right of a state to file 
a section 126 petition does not have any time limitation, and the EPA 
is required to act quickly whenever presented with such a petition. The 
commenters' arguments that a section 126 petition cannot be filed, or a 
section 126 finding cannot be made, before the 110(a)(2)(D) SIP 
submission deadline passes are policy arguments with no basis in the 
statutory text. Instead, as discussed below, the statutory text, the 
structure of the CAA, and the legislative history all support the EPA's 
interpretation of the Act as creating, in sections 110 and 126, two 
independent means of controlling transboundary emissions and find no 
support for the argument that one should be prioritized over the other.
    Moreover, the plain language of the statute does not clearly define 
``prohibition'' to mean a SIP provision that sets emissions limits to 
address transboundary air pollution. Rather, the EPA believes that the 
better interpretation, in light of the structure of the CAA and its 
legislative history, is that the ``prohibition'' referred to in section 
126 is the actual, functional prohibition on transboundary air 
pollution contained in section 110(a)(2)(D)(i).
    The commenters' interpretation of the ``prohibition'' referred to 
in section 126 would render the relief provided by a section 126 
petition process essentially meaningless. If a source is emitting in 
violation of an emission limitation in a SIP, there is no question that 
the source is in violation of the SIP. The language in section 126 
stating that ``it shall be a violation of * * * the applicable 
implementation plan'' for a source to emit in violation of the 
prohibition of section 110(a)(2)(D) serves no legal purpose where the 
source is already directly violating a SIP requirement. By contrast, 
under the EPA's interpretation, section 126 deems a source's emissions 
to be a violation of the applicable SIP (as well as of section 126) 
whenever the emissions significantly contribute to nonattainment 
downwind or interferes with maintenance of any NAAQS. This 
interpretation gives legal effect to the language in section 126 and is 
consistent with Congress' purpose of providing a tool for downwind 
states and the EPA to use to impel upwind sources to reduce transported 
emissions even where a SIP may not yet directly regulate such 
emissions.
    Moreover, the EPA's interpretation of section 126 gives it a 
purpose independent of the other remedies available under the CAA. 
Under section 113, upon finding that any person is in violation of any 
requirement of an approved SIP, the EPA has the authority to enforce 
the requirement by issuing an order to comply, issuing an 
administrative penalty order, or bringing a civil action. In addition, 
any person (which includes states) may bring a citizen suit against any 
person in violation of any requirement of an approved SIP, independent 
of the EPA action. Section 304(a), (f); see also section 302. These 
provisions provide more direct and likely quicker recourse against a 
source that is violating its SIP-imposed emission limits than the 
section 126 petition process would. Thus, there is no need to have a 
petition, public hearing, and EPA determination pursuant to section 126 
simply to enforce existing SIP limits. By contrast, using the section 
126 petition process where transboundary emissions are not yet being 
controlled by an upwind state serves the unique role of allowing a 
downwind state to force the EPA's consideration of the problem and 
potentially achieve emissions reductions directly from sources, without 
the need to depend on action by the upwind state.
    The EPA's interpretation of the relationship between sections 126 
and 110 is expressly supported by the legislative history of the CAA. 
In adopting the section 126 remedies, Congress explained that the 
petition process was intended to provide an avenue for relief separate 
from the section 110(a)(2)(D) SIP procedure:

    This petition process is intended to expedite, not delay, 
resolution of interstate pollution conflicts. Thus, it should not be 
viewed as an administrative remedy which must be exhausted prior to 
bringing suit under section 304 of the act. Rather, the committee 
intends to create a second and entirely alternative method and basis 
for preventing and abating interstate pollution. The existing 
provision prohibiting any stationary source from causing or 
contributing to air pollution which interferes with timely 
attainment or maintenance or [sic] a national ambient air standard 
(or a prevention of significant deteriorating [sic] or visibility 
protection plan) in another state is retained. A new provision 
prohibiting any source from emitting any pollutant after the 
Administrator has made the requisite finding and granted the 
petition is an independent basis for controlling interstate air 
pollution.

H. Rep. 95-294 at 305, reprinted in 1977 Legislative History at 2798. 
Nothing in the legislative history suggests, as the commenters assert, 
that the section 126 remedy is dependent on the section 110 SIP 
procedure. Rather, this language clearly indicates that Congress 
intended sections 110 and 126 to operate as independent means of 
controlling transboundary emissions and that it did not intend to 
prioritize one means of control over the other. Accordingly, there is 
no basis in the legislative history to support the commenters' argument 
that a state does not have the right to submit a section 126 petition 
until after the deadline to submit a section 110(a)(2)(D) SIP has 
passed. To the contrary, the legislative history supports the 
conclusion that Congress did not intend to impose any limitation

[[Page 69056]]

tied to the section 110(a)(2)(D) SIP procedure on when a state may 
submit a section 126 petition after a new or revised NAAQS is 
promulgated.
    Moreover, Congress recognized in adopting all of the interstate 
transport provisions in the CAA that the interstate pollution problem 
stems from inadequate limits on transported emissions, and not 
inadequate compliance with adequate SIP requirements. This 
characterization of the problem is supported by the numerous 
descriptions of the interstate pollution problem in the 1977 
legislative histories, all of which explicitly or implicitly refer to 
the lack of upwind limitations and none of which mentions sources' 
violation of upwind SIP limits. See, e.g,. S. Comm. on Envt. and Public 
Works, Clean Air Act Amendments of 1977, S. Rep. 95-127, 95th Cong., 
1st Sess. 41 (1977), reprinted in 3 1977 Legislative History at 1415 
(noting that the 1970 Act failed to specify any abatement procedure if 
a source in one state emitted air pollutants that adversely affected 
another state, and ``[a]s a result, no interstate enforcement actions 
have taken place, resulting in serious inequities among several States, 
where one State may have more stringent implementation plan 
requirements than another state''); H. Rep. 95-294, 95th Cong., 1st 
Sess. at 304 (1977), reprinted in 4 1977 Legislative History at 2798 
(``[A]n effective program must not rely on prevention or abatement 
action by the State in which the source of the pollution is located, 
but rather by the state (or residents of the State) which receives the 
pollution and the harm, and thus which has the incentive and need to 
act.''). It is reasonable to assume that Congress intended to create a 
tool that would attack the problem Congress recognized. This supports 
the conclusion that Congress intended section 126 to provide an 
alternate means to compel compliance with the prohibition in section 
110(a)(2)(D) where upwind states are not controlling transboundary 
emissions, and not where sources are violating adequate SIP provisions.
    The interpretation that the EPA adopts here is also consistent with 
its historical interpretation of section 126. The EPA previously 
interpreted this section in two rulemakings issued in 1999 and 2000, 
wherein commenters challenged the EPA's authority, in light of a 
pending SIP call, to grant a number of section 126 petitions that 
sought to mitigate the transport of nitrogen oxides (NOX) 
from downwind states that were significantly contributing to ozone 
nonattainment problems in the petitioning states. 64 FR 28250; 65 FR 
2674. In both rulemakings, the EPA interpreted the relationship between 
sections 110 and 126 consistent with the EPA's interpretation here, 
concluding that the ``prohibition'' referred to in section 126 is the 
functional prohibition of section 110(a)(2)(D)(i), as opposed to an 
emissions limitation contained in a state's SIP, and that the section 
110(a)(2)(D) SIP process and the section 126 petition process are 
independent and alternative means of addressing impermissible 
interstate transport.
    Both rulemakings were challenged in the DC Circuit in Appalachian 
Power Co. v. EPA, 49 F.3d 1032 (2001), on the theories that the agency 
was required to refrain from making any section 126 findings while the 
SIP call was ongoing and that the doctrine of ``cooperative 
federalism'' embodied in the Act imposed a constraint on the EPA's 
ability to act before the section 110 process was complete. Id at 1045. 
The court deferred to the EPA's interpretation of the relationship 
between sections 110 and 126, holding that there is no inherent 
conflict in acting on a section 126 petition during the same period 
that a state has to develop a SIP submission: ``It is entirely 
reasonable for the EPA to regard a state that is under a legal 
obligation to revise its plan as being, in the meantime, in violation 
of a functional prohibition.'' Id. at 1046. The court explained that 
the petitioners' interpretation of section 126 would compromise three 
critical provisions of section 126:
    1. The requirement that source operate no more than 3 years after 
finding of contribution to downwind nonattainment;
    2. The fact that ``relief does not depend upon any action by the 
upwind states, as is necessary for a SIP revision''; and
    3. The fact that relief under section 126 is independent of the 
discretionary policy preferences of the EPA, as the agency is required 
to act upon a petition within 60 days.

Id. The court noted that the EPA's interpretation retains all three 
aspects of the statutory requirements.
Id. The court therefore concluded that ``[b]ecause it is reasonable, 
and because the `Congress provided both [Sec. Sec.  110 and 126] 
without indicating any preference for one over the other,' * * * the 
EPA's conclusion that these two provisions operate independently merits 
our deference under Chevron step two.'' Id. at 1048 (quoting 65 FR at 
2680/1).

    Thus, the EPA believes that the commenters' interpretation of 
section 126 is unreasonable and inconsistent with the legislative 
history, the EPA's past interpretations, and court rulings upholding 
those interpretations. In particular, the commenters' interpretation 
would render the relief provided by the section 126 petition process 
duplicative and unnecessary. The EPA's interpretation, on the other 
hand, gives legal effect to the language in section 126 and is 
consistent with Congress' purpose of providing an independent tool for 
a downwind states and the EPA to use to impel upwind sources to reduce 
transported emissions. The EPA believes this matter is clearly resolved 
by reference to the terms of the provision itself, so that under the 
first step of the Chevron analysis, no further inquiry is needed. If, 
however, it were concluded that the provision is ambiguous on this 
point, the EPA believes that, under the second step in the Chevron 
analysis, then the EPA should be given deference for any reasonable 
interpretation, as courts have given with respect to prior 
interpretations of section 126. Interpreting section 126 to refer to a 
functional prohibition on emissions and to preserve a state's right to 
file a section 126 petition is reasonable for the reasons described 
above.
    Comment: Several commenters argue that the EPA is turning to 
section 126 as a ``first resort'' for implementing the new NAAQS and 
that we are substituting the EPA's judgment for Pennsylvania's 
regarding the appropriate control strategy for Portland. The commenters 
contend that revising Pennsylvania's SIP is a usurpation of state 
discretion and that the SIP process would be superfluous if we allowed 
petitions to be filed so close on the heels of new or revised NAAQS. 
The commenters believe that Congress intended states to have primary 
responsibility for implementing a new or revised NAAQS. They contend 
that the EPA's interpretation of section 126 places priority on 
interstate transport over intrastate control of NAAQS attainment.
    Response: We respond by noting that the upwind state still retains 
its obligation to develop a SIP and implement the NAAQS. Applying 
section 126 independent of an upwind state's failure to act under 
section 110(a)(2)(D) does not impermissibly pressure upwind states to 
select certain control measures. The EPA acknowledges that because the 
section 126 findings precede any required state action, when states are 
eventually required to submit SIPs to control interstate transport, one 
of the largest sources of emissions will already be subject to emission 
control

[[Page 69057]]

requirements, and, depending upon the timing, may have already invested 
in controls. Yet this is not a legal constraint on states' choices--it 
is the reality that, over time, conditions change and different policy 
choices become more or less attractive for a variety of reasons. States 
would still be able to choose to regulate other sources, but depending 
upon the timing, the option of obtaining emission reductions from 
sources that have already invested in emission controls or have already 
reduced emissions may be more attractive on policy and economic grounds 
than regulating those sources otherwise would have been. There is a 
vast difference between, on one hand, the EPA prescribing a particular 
emissions control choice that states must adopt, and on the other, 
taking action required under the CAA to regulate sources directly with 
the possible effect of making certain future emissions control choices 
by some states more or less appealing.
    Such a potential future effect on the regulatory environment cannot 
override the obligation that the EPA act on state petitions under 
section 126. We do not believe it would be reasonable to conclude that 
the EPA can take no action under an independent mandate of the statute 
to respond to petitions submitted by downwind states facing their own 
time constraints and pressures to meet air quality standards, just to 
preserve the relative attractiveness of a variety of options for 
control of SO2 in the upwind states required under another 
provision of the CAA. The cooperative federalism principles of the CAA 
do not require the EPA to withhold federal action under section 126 
until states have been required to and failed to submit SIPs. It is 
perfectly reasonable for Congress to have established section 126 as an 
alternative mechanism under the CAA to address the interstate pollution 
problem, just as it did again in adopting sections 176A and 184. To 
provide alternatives, the various interstate transport provisions are 
necessarily different from each other and from other provisions of the 
Act, but that does not make them inconsistent with other provisions of 
the Act. Thus, simply because the EPA will have imposed certain 
requirements on Portland does not mean that Pennsylvania no longer has 
any discretion in crafting its SIP submission with respect to NAAQS 
compliance anywhere in the state. Pennsylvania can take into 
consideration the controls that Portland chooses to implement when 
creating its own attainment plan, just as it would take into 
consideration controls implemented at any other source.
    The court in Appalachian Power Co. v. EPA specifically addressed 
this concern that action on the section 126 petition before the SIP 
submissions were due would restrict the states' discretion to fashion 
their own plan for complying with the NAAQS: ``SIP development, like 
any environmental planning process, commonly involves decisionmaking 
subject to various legal constraints. That Sec.  126 imposes one such 
limitation--and it is surely not the only independent provision of 
federal law to do so--does not affect a state's discretion under Sec.  
110.'' 49 F.3d at 1047.
    Finally, as explained in detail above, Congress intended sections 
110 and 126 to operate as independent and alternate means to address 
transboundary pollution, and indicated no preference for one means of 
compelling compliance over the other. Thus, the EPA's action on this 
section 126 petition does not prioritize the control of interstate 
pollution over a state's control of intrastate pollution. Rather, it 
gives legal effect to section 126, consistent with the structure of the 
CAA and the legislative history, by providing a tool for downwind 
states to use to impel upwind sources to reduce transported emissions.

IV. Summary and Assessment of the Modeling and Other Data Relevant to 
the EPA's Proposed Finding

A. Summary of the Modeling for the Proposed Rule

    NJDEP's section 126 petition contained dispersion modeling results, 
based on both the CALPUFF \4\ and AERMOD dispersion models, that NJDEP 
relied upon to show that emissions from Portland, alone, caused 
downwind violations of the 1-hour SO2 NAAQS in New Jersey. 
Given the magnitude of the modeling violations, which were nearly seven 
times the 1-hour SO2 NAAQS based on AERMOD modeling of 
maximum allowable emissions, and the fact that significant exceedances 
of the NAAQS were also shown based on modeling of estimated actual 
emissions, the EPA concluded that the NJDEP had clearly shown that 
SO2 emissions from Portland cause violations of the 1-hour 
SO2 NAAQS in New Jersey.
---------------------------------------------------------------------------

    \4\ CALPUFF is a non-steady-state puff dispersion model that was 
originally developed for the California Air Resources Board.
---------------------------------------------------------------------------

    The EPA also modeled the emissions from Portland using the AERMOD 
dispersion model and determined that the modeled concentrations from 
Portland, when combined with the relatively low background 
concentrations, cause violations of the 1-hour SO2 NAAQS in 
Morris, Sussex, Warren and Hunterdon Counties in New Jersey.\5\ This 
section discusses the key modeling issues that arise in making that 
determination, and how the EPA is responding to comments we received on 
those issues. We also note that this modeling is used not only to 
characterize the NAAQS violations, but, as discussed in section V, it 
is also used to determine the appropriate remedy to address such 
violations.
---------------------------------------------------------------------------

    \5\ The EPA modeling analysis is detailed in the proposed rule 
Air Quality Modeling Technical Support Document, available in Docket 
ID EPA-HQ-OAR-2011-0081-0026.
---------------------------------------------------------------------------

1. Modeling Analysis in NJDEP's Section 126 Petition
a. Model Selection
    Model selection was one of the key issues that the EPA addressed in 
support of this rule given the critical role played by dispersion 
modeling both in relation to a finding under a section 126 petition 
that a source significantly contributes to nonattainment and/or 
interferes with maintenance of the 1-hour SO2 NAAQS in a 
neighboring state, and in relation to the determination of an 
appropriate remedy to address such a finding. As summarized in the 
proposed rule and documented in more detail in the EPA's proposed rule 
Air Quality Modeling Technical Support Document, NJDEP included 
modeling results based on both the CALPUFF and AERMOD dispersion models 
with its section 126 petition. The importance of this issue is further 
highlighted by the fact that the maximum 99th percentile of the daily 
maximum 1-hour modeled SO2 concentrations based on CALPUFF 
was about 2.5 times higher than the maximum 99th percentile of the 
daily maximum 1-hour modeled concentrations based on AERMOD. 
Consequently, a much more stringent remedy would be required to address 
such a finding based on CALPUFF modeling than based on AERMOD modeling.
    The NJDEP acknowledged that AERMOD is the preferred model under the 
EPA's ``Guideline on Air Quality Models,'' published as Appendix W to 
40 Code of Federal Regulations (CFR) Part 51, for near-field 
applications such as this, but suggested that the use of CALPUFF may be 
appropriate under the alternative model provisions in Section 3.2.2b of 
Appendix W. Section 3.2 of Appendix W lists three separate conditions 
under which an alternative model may be approved for use:

[[Page 69058]]

    (1) If a demonstration can be made that the model produces 
concentration estimates equivalent to the estimates obtained using a 
preferred model;
    (2) If a statistical performance evaluation has been conducted 
using measured air quality data and the results of that evaluation 
indicate the alternative model performs better for the given 
application than a comparable model in Appendix A of Appendix W; or
    (3) If the preferred model is less appropriate for the specific 
application, or there is no preferred model.
    The NJDEP modeling documentation suggested that NJDEP's use of the 
CALPUFF model in support of this petition was based on condition (2) of 
Section 3.2.2b, claiming to have shown that CALPUFF ``performed better 
and produced predictions of greater accuracy than AERMOD'' for this 
application. NJDEP also claimed that the use of CALPUFF is more 
appropriate for this specific application due to the complex winds 
addressed in Section 7.2.8 of Appendix W and is therefore justified 
under condition (3) of Section 3.2.2b.
    The section 126 petition referenced a CALPUFF model validation 
study based on the Martin's Creek field study database, submitted by 
NJDEP with an earlier section 126 petition, as demonstrating that 
``CALPUFF performed better and produced predictions of greater accuracy 
than AERMOD'' for this application.\6\
---------------------------------------------------------------------------

    \6\ See Letter from Bob Martin, Commissioner, New Jersey 
Department of Environmental Protection (NJDEP) to Lisa P. Jackson, 
Administrator, USEPA (September 13, 2010), Section IV, page 5. 
Docket ID No. EPA Docket, EPA-HQ-OAR-2011-0081-009.
---------------------------------------------------------------------------

    At proposal, the EPA included a detailed assessment of the NJDEP 
CALPUFF validation study as Appendix A of the proposed rule Air Quality 
Modeling TSD, and concluded that NJDEP had not adequately justified the 
use of CALPUFF in this application under either conditions (2) or (3) 
of Section 3.2.2b of Appendix W. The EPA further asserted that AERMOD 
is the most appropriate model for this application. Our assessment of 
the CALPUFF validation study identified several aspects of NJDEP's 
validation methodology that deviated from the EPA's Protocol for 
Determining the Best Performing Model,\7\ which undermined the 
integrity of the evaluation results. In addition, we cited the ``weight 
of evidence'' regarding AERMOD model performance which is based on 
evaluations for a total of 17 field study databases as compared to 
NJDEP's CALPUFF validation study which is the only near-field 
evaluation of CALPUFF model performance that the EPA is aware of that 
included CALMET-generated 3-dimensional wind fields. We also pointed to 
the fact that the 1-hour, 3-hour and 24-hour quantile-quantile (Q-Q) 
plots of modeled versus observed concentrations for AERMOD and CALPUFF 
included in the NJDEP validation study suggested that the performance 
of the CALPUFF and AERMOD models was very similar for this database, 
with both models exhibiting generally good agreement with observations, 
but with AERMOD showing slightly better overall agreement than CALPUFF. 
These clear visual comparisons of model performance are difficult to 
reconcile with NJDEP's assertion that CALPUFF performed better than 
AERMOD.
---------------------------------------------------------------------------

    \7\ Protocol for Determining the Best Performing Model. EPA-454/
R-92-025 (1992). U.S. Environmental Protection Agency, Research 
Triangle Park, NC, available at: http://www.epa.gov/ttn/scram/guidance/guide/modleval.zip.
---------------------------------------------------------------------------

b. Meteorological Data
    Another key component of the dispersion modeling analysis is the 
meteorological data. The EPA based the AERMOD modeling in support of 
the proposed rule on 1 year of Portland site-specific meteorological 
data available for July 1993 through June 1994. The site-specific 
meteorological data were collected from a 100-meter instrumented tower 
and Sound Detection and Ranging instrument (SODAR), located about 2.2 
kilometers west of Portland. Based on a review of the data, we 
determined that the Portland meteorological data from 1993-94 meet the 
basic criteria for representativeness under Section 8.3.3 of Appendix 
W, and therefore can be considered as site-specific data for purposes 
of modeling impacts from the elevated stacks for Portland units 1 and 
2. The 1993-94 data also meet the minimum criterion for the length of 
meteorological data record of at least 1 year of site-specific 
meteorological data recommended in Section 8.3.1.2 of Appendix W. 
However, the difference of about 100 meters in the base elevation for 
the meteorological tower versus the stack base elevation raised 
concerns regarding how the meteorological data were input to the AERMOD 
model in the NJDEP modeling analysis given that the stack heights for 
units 1 and 2 are about 122 meters and that plume heights of concern 
for units 1 and 2 are about 200 to 400 meters above stack base.
    The AERMOD modeling submitted by NJDEP used the measurement heights 
above local ground at the tower location for the meteorological data 
input to the model, effectively assuming that the measured profiles of 
wind, temperature and turbulence are ``terrain-following.'' Without 
adjusting for the difference in base elevation of about 100 meters 
between the meteorological data and the stacks, wind speeds are likely 
to be biased high and the wind directions may not be representative of 
plume heights relative to stack base. A review of the raw 
meteorological data files for Portland also revealed the fact that 
[sigma]w (vertical turbulence) data were available from the 
SODAR, but had not been used in the AERMOD modeling submitted with 
NJDEP's section 126 petition. Based on the analyses that are described 
in more detail in the EPA proposed rule Air Quality Modeling TSD, the 
EPA concluded that the representativeness of the Portland 
meteorological data would be improved by incorporating some adjustments 
to the measurement heights from the SODAR data and the inclusion of the 
[sigma]w data collected from the SODAR.
2. The EPA's Modeling Analysis To Quantify Significant Contribution
    In the EPA AERMOD modeling analysis, thousands of receptors were 
placed in New Jersey to determine the area of maximum concentration 
from Portland's emissions in order to quantify Portland's significant 
contribution to nonattainment in New Jersey. A design value 
concentration was calculated for each receptor for comparison to the 
NAAQS. The design value concentration is equal to the 99th percentile 
(4th-highest) of the annual distribution of daily maximum 1-hour 
SO2 concentrations. All receptors with modeled design value 
concentrations that are greater than the NAAQS [196.2 micrograms per 
cubic meter (ug/m\3\)] \8\ are determined to be nonattainment 
receptors.
---------------------------------------------------------------------------

    \8\ The 1-hour SO2 NAAQS is 75 ppb. For comparison to 
dispersion modeling results in units of ug/m\3\, the NAAQS can be 
expressed as 196.2 ug/m\3\, assuming reference temperature and 
pressure.
---------------------------------------------------------------------------

    The EPA proposed to define Portland's significant contribution to 
nonattainment and interference with maintenance as those emissions that 
must be eliminated to bring the downwind receptors in New Jersey 
affected by Portland into modeled attainment in the analysis year. 
While this approach would not be appropriate in every circumstance, the 
EPA believes it is appropriate where, as here, the source's emissions 
are sufficient on their own to cause downwind NAAQS violations and 
background levels of the relevant pollutant are relatively low. The EPA 
therefore developed a

[[Page 69059]]

methodology to identify the reductions necessary to bring the downwind 
receptors into attainment.
    To quantify the emissions that constitute Portland's significant 
contribution, the EPA identified the level of emissions that need to be 
reduced to ensure that no modeled concentration within the affected 
area (in New Jersey) exceeds the level of the NAAQS (i.e., the 99th 
percentile of the daily maximum 1-hour average of 196.2 ug/m\3\).
    The EPA also analyzed the modeling results to determine the 
appropriate emissions reductions that were needed to eliminate 
``interfere with maintenance.'' In addition to nonattainment receptors, 
the EPA also attempted to identify receptors that are modeled to be 
attainment but due to variability in meteorology or emissions might be 
at risk for nonattainment. Due to the high modeled concentrations from 
Portland's emissions, all of the downwind modeled receptors in the 
final modeled receptor grid in New Jersey are modeled to be 
nonattainment. In this application, it was not necessary to expand the 
modeling grid to identify additional nonattainment or ``maintenance 
only'' receptors because the modeling domain was focused on the 
receptors with the maximum impact from Portland. Therefore, the EPA did 
not identify any ``maintenance only'' receptors.
    In the proposal, the EPA considered whether Portland should be 
required to make additional reductions, above and beyond those required 
to eliminate its significant contribution to nonattainment, to ensure 
that it does not interfere with maintenance of the 1-hour 
SO2 NAAQS in violation of the prohibition in section 
110(a)(2)(D). We identified an approach that we believe is appropriate 
for these specific circumstances. Among other things, we considered the 
nature of the modeling used to determine the appropriate remedy and the 
potential for actual SO2 concentrations in New Jersey to be 
higher than those modeled. In the proposal, the EPA determined there is 
no indication that concentrations higher than those modeled from 
Portland would be likely to occur at nonattainment and/or maintenance 
receptors or anywhere else in New Jersey. This was based on the 
following facts:
    1. There is only 1 year of site-specific meteorology available, 
such that we were not able to explicitly examine the impact of year-to-
year variability of meteorology on downwind modeled concentrations.\9\
---------------------------------------------------------------------------

    \9\ Due to constraints on data availability, our analysis is 
appropriate in this instance; however, nothing here is intended to 
suggest that, where sufficient data are available to examine year-
to-year variability, this should not be a relevant factor.
---------------------------------------------------------------------------

    2. The remedy modeling used maximum allowable emissions from 
Portland. Since these are the highest emissions that are allowed to be 
emitted by the facility, higher concentrations could not be expected to 
occur in New Jersey due to the variability of emission from Portland.
    3. In the modeling analysis, we used background concentrations that 
varied by season and hour of day based on the 3-year average of the 
99th percentile of the distribution of hourly SO2 
concentrations in the area, which represents the high end of the 
distribution of monitored background concentrations. The background 
concentration accounts for contributions from other SO2 
sources. As demonstrated by NJDEP's trajectory analysis,\10\ it is 
likely that SO2 impacts from Portland contributed to some of 
the high monitored concentrations at the Chester, New Jersey, monitor 
used to represent the background concentrations, which is located about 
34 kilometers east-southeast of Portland. Although use of the 99th 
percentile values by season and hour of day from the Chester, New 
Jersey, monitor eliminated some of the peak hourly SO2 
concentrations, the background concentrations are still likely to be 
somewhat conservative (high) to account for variability that otherwise 
cannot be quantified.
---------------------------------------------------------------------------

    \10\ See Trajectory Analysis of High Sulfur Dioxide Episodes at 
the Chester, NJ Monitor. Bureau of Technical Services, Division of 
Air Quality, New Jersey Department of Environmental Protection. July 
30, 2010. Submitted to USEPA as Exhibit 4 of the September 13, 2010 
Supplement to New Jersey's May 12, 2010 Petition Pursuant to Section 
126 of the Clean Air Act, 42 U.S.C. 7426. Docket ID No. EPA Docket, 
EPA-HQ-OAR-2011-0081-008.
---------------------------------------------------------------------------

    It was therefore reasonable to conclude, under the circumstances, 
that any remedy that eliminates the significant contribution to 
nonattainment from Portland also eliminates its interference with 
maintenance with respect to year-to-year variability in emissions and 
meteorology. The EPA therefore proposed to find that compliance by 
Portland with the proposed emission limits will bring it into 
compliance with the prohibition on emissions that significantly 
contribute to nonattainment of the 1-hour SO2 NAAQS as well 
as with the prohibition on emissions that interfere with maintenance in 
a downwind area. The EPA requested comments on our modeling methodology 
and meteorological data adjustments.

B. Public Comments Related to the Modeling

    We received many public comments related to the modeling that was 
used to support the finding that SO2 emissions from Portland 
contribute significantly to nonattainment and interfere with 
maintenance of the 1-hour SO2 NAAQS in New Jersey. Some of 
the main comments and the EPA's responses related to model selection, 
meteorological data, emissions and source characteristics, and 
background concentrations are summarized below, with further details 
provided in the Response to Comments document.
1. Model Selection
    Comments: We received several comments supporting the EPA's 
conclusion that AERMOD is the appropriate dispersion model for this 
petition, and that also supported the EPA's overall assessment that 
NJDEP's CALPUFF validation study failed to demonstrate that CALPUFF 
performs better for this application than AERMOD. One commenter (NJDEP) 
believes that the modeling in support of the section 126 petition 
should be based on CALPUFF, and provided detailed comments on the EPA 
assessment of the CALPUFF validation study.
    Response: As discussed in greater detail in the final rule Air 
Quality Modeling technical support document (final rule Modeling TSD), 
the EPA review of NJDEP's comments related to our assessment of the 
CALPUFF validation study has identified additional deficiencies with 
the study that further undermine NJDEP's conclusion that ``CALPUFF 
performed better and produced predictions of greater accuracy than 
AERMOD'' for this application. One of these deficiencies that came to 
light upon closer examination of the CALPUFF modeling files for the 
validation study is that NJDEP used the ``ISC Type'' option for 
building downwash in CALPUFF instead of the PRIME \11\ downwash option 
when applying CALPUFF for the Martin's Creek validation study, although 
the CALPUFF input file

[[Page 69060]]

included the necessary building input parameters to run the PRIME 
option. The AERMOD modeling results for Martin's Creek used for 
comparison were based on the PRIME downwash algorithm. While building 
downwash associated with the cooling towers at Martin's Creek exhibited 
only a modest influence on results based on AERMOD evaluations, it is 
important enough to be treated properly in the model evaluation, and 
the EPA concludes that the PRIME downwash option should have been used 
in the CALPUFF modeling since AERMOD's promulgation effectively 
established the PRIME algorithm as the ``preferred'' downwash algorithm 
for near-field applications. NJDEP's CALPUFF validation report 
identifies that the ``ISC type'' downwash option was used in the table 
of CALPUFF inputs (the MBDW parameter in Table 8.2), but provides no 
explanation or justification for not using the PRIME downwash option. 
As described in more detail in the final rule Modeling TSD, the 
inclusion of the PRIME downwash option in CALPUFF resulted in a greater 
tendency for CALPUFF to overestimate concentrations at Martin's Creek 
as compared to the ``ISC-Type'' downwash option, with some 
deterioration in model performance metrics.
---------------------------------------------------------------------------

    \11\ The ``ISC Type'' building downwash option in CALPUFF refers 
to the Huber-Snyder and Schulman-Scire algorithms that are 
incorporated in the Industrial Source Complex Short Term (ISCST3) 
model. The PRIME downwash option refers to the ``Plume Rise Model 
Enhancements'' algorithms that were initially incorporated into a 
revised version of ISCST3 called ISC-PRIME, and were later 
incorporated into the AERMOD model prior to its promulgation as the 
EPA-preferred model for near-field applications, replacing ISCST3, 
in 2005.
---------------------------------------------------------------------------

    Additional evidence supporting the EPA's determination that AERMOD 
is a more appropriate model for this application than CALPUFF was 
provided by an EPA analysis of high modeled SO2 
concentrations versus high observed SO2 concentrations at 
the Columbia Lake Wildlife Management (Columbia) air quality monitor 
located in New Jersey about 2 kilometers northeast of Portland. The EPA 
compared the observed SO2 data from September 2010 through 
September 2011 to modeled concentrations from AERMOD and CALPUFF. 
Although the monitored concentrations are based on a different period 
than the modeled concentrations (1993-94 in the case of AERMOD, and 
1992-93, and 2002 for CALPUFF), it is reasonable to expect some degree 
of comparability between modeled and monitored concentrations based on 
the upper end of the ranked concentration distributions. These 
comparisons, which were patterned after comparisons presented in 
NJDEP's trajectory analysis report for the Columbia monitor \12\ and 
are described in more detail in the final rule Modeling TSD, show 
generally good agreement with observations based on AERMOD modeling, 
utilizing the EPA's adjustments \13\ to the 1993-94 site specific 
meteorological data for Portland. The EPA analysis used an emission 
scenario of 100 percent load and 70 percent of allowable emissions for 
Portland units 1 and 2, which is representative of peak operating 
conditions for Portland during the period of monitoring data and 
reflects the fact that the sulfur content of the fuel being burned at 
Portland was typically about 70 percent of the allowable sulfur 
content. Since Portland frequently operates well below these levels, we 
would expect to see some bias toward overestimation in the modeled 
concentrations, and the AERMOD predictions are consistent with that 
expectation. The average ratio of predicted to observed concentrations 
for the top 10 daily maximum 1-hour values was 1.14. By comparison, the 
average predicted/observed ratio for AERMOD for the same emission 
scenario using NJDEP's meteorological data for Portland without the 
EPA's adjustments was 0.77. The modeled concentrations are based on 
both units 1 and 2 operating at 100 percent load and 70 percent of 
allowable emissions, without any contribution from background 
concentrations. The relatively good model performance for AERMOD is in 
contrast to a large over-prediction when CALPUFF results are compared 
to observed SO2 at the Columbia monitor. The average 
predicted/observed ratios for CALPUFF were about 3.26 for the 1992-93 
meteorological data and 3.87 for the 2002 meteorological data. 
Additional details regarding these analyses related to the Columbia 
monitoring data are provided in the EPA final rule Modeling TSD.
---------------------------------------------------------------------------

    \12\ Analysis of the Sulfur Dioxide Measurements from the 
Columbia Lake, NJ Monitor. Bureau of Technical Services, Division of 
Air Quality, New Jersey Department of Environmental Protection, 
March 4, 2011. Docket ID No. EPA-HQ-OAR-2011-0081-0019.
    \13\ As documented in Appendix B of the EPA proposed rule Air 
Quality Modeling TSD, the EPA adjusted some of the measurement 
heights from the SODAR data and also included the SODAR-derived 
[sigma]w data.
---------------------------------------------------------------------------

2. Meteorological Data
    Comments: GenOn submitted comments indicating general agreement 
with the EPA adjustments to the Portland meteorological data, although 
it recommended also including the turbulence data from the 30-meter 
level on the instrumented tower, including both [sigma]w and 
[sigma]u (lateral turbulence), which had been excluded from the EPA 
modeling in support of the proposal.
    Response: We disagree with GenOn's recommendation to include the 
30-meter turbulence data due to the concerns regarding the 
representativeness of such data, which are documented in the proposed 
rule Air Quality Modeling TSD. The EPA explained that it excluded the 
30-meter turbulence data due to concerns regarding the 
representativeness of the data at that level relative to stack base 
elevation given that the measurement heights from the 100-meter tower 
were not adjusted and would therefore be treated as being 
representative of meteorological conditions within the valley.
    We also note that inclusion of the 30-meter turbulence data would 
have a negligible effect on the modeling results since the elevated 
plumes from Portland units 1 and 2 will be well above 30 meters such 
that transport and dispersion of the plumes will be determined by 
measurements at higher levels from the tower and SODAR. Therefore, the 
30-meter turbulence data is only expected to influence the plumes in 
the rare cases where turbulence data were missing from the 100-meter 
level on the tower and from the SODAR. Due to the representativeness 
issues, we believe it would be inappropriate to rely on the 30-meter 
turbulence data in those cases.
    Comment: NJDEP submitted detailed comments opposing the EPA's 
adjustments to the Portland meteorological data, as well as other 
aspects of the meteorological data processing. NJDEP's opposition to 
the EPA adjustments to Portland meteorological data primarily concerned 
past precedents regarding prior modeling analyses based on the data, 
the lack of field study evaluation results validating the use of SODAR-
derived [sigma]w data in AERMOD, and the fact that the net 
effect of the meteorological data adjustments incorporated in the EPA 
modeling reduced the overall modeled design value by about 40 percent 
as compared to the AERMOD modeling results submitted by NJDEP with the 
section 126 petition.
    Response: Regarding the exclusion of SODAR-derived 
[sigma]w data in past analyses, we noted that the EPA 
meteorological monitoring guidance prior to 2000 discouraged the use of 
SODAR-derived turbulence data, including [sigma]w. However, 
we also note that the updated guidance issued by the EPA in 2000 \14\ 
supports the use of SODAR-derived [sigma]w based on 
additional analyses of SODAR versus tower-based [sigma]w 
data. Furthermore, as mentioned

[[Page 69061]]

above in relation to the issue of model selection and as documented in 
more detailed in the final rule Modeling TSD, additional analyses based 
on model-to-monitor comparisons against the Columbia, New Jersey, 
ambient SO2 data show much better agreement between modeled 
and monitored concentrations based on the EPA-adjusted meteorological 
data than for the unadjusted data used by NJDEP in its AERMOD modeling, 
which tends to corroborate the EPA adjustments to the meteorological 
data. As shown in NJDEP's trajectory analysis for the Columbia monitor 
(NJDEP, March 4, 2011) and further documented in the final rule 
Modeling TSD, AERMOD modeling based on the unadjusted data used by 
NJDEP exhibits a tendency to underestimate ambient concentrations as 
compared to the Columbia monitored data. Although these analyses lend 
some credence to the appropriateness of the EPA meteorological data 
adjustments, we believe that the adjustments are fully justified based 
on current EPA meteorological monitoring guidance as well as technical 
considerations, in relation to the approximately 100 meter difference 
between the base elevation of the meteorological tower/SODAR and the 
base elevation of the Portland stacks as documented in more detail in 
the EPA final rule Modeling TSD.
---------------------------------------------------------------------------

    \14\ Meteorological Monitoring Guidance for Regulatory Modeling 
Applications, EPA-454/R-99-005 (February 2000). U.S. Environmental 
Protection Agency, Research Triangle Park, NC, available at: http://www.epa.gov/ttn/scram/guidance/met/mmgrma.pdf
---------------------------------------------------------------------------

    Regarding the fact that the maximum 99th percentile 1-hour 
SO2 modeled design value based on the EPA analysis including 
adjustments to the meteorological data was about 40 percent lower than 
the maximum 99th percentile design value based on the NJDEP AERMOD 
modeling (1,402 ug/m\3\ versus 851 ug/m\3\), we also note that the EPA-
modeled results are in fact higher than the NJDEP results across most 
of the final modeled domain. More specifically, the EPA modeled results 
are higher than the NJDEP results for about 96 percent of the modeled 
receptors in the final 100-meter receptor grid, and the average 
difference across all receptors was about 44 percent higher based on 
the EPA modeling.
    Based on this review of comments submitted regarding the EPA 
adjustments to the Portland meteorological data and in light of 
additional evidence supporting the appropriateness of the adjustments 
based on model-to-monitor comparisons for the Columbia, New Jersey, 
ambient monitor, no changes relative to the proposal have been made to 
the meteorological data used in the EPA AERMOD modeling in support of 
this final action.
    Comment: A few commenters raised concerns regarding the fact that 
the EPA AERMOD modeling relied upon a single year of site-specific 
meteorological data. One commenter suggested that a more conservative 
estimate of the modeled design value used compensated for this, such as 
the highest second-highest concentration rather than the 99th 
percentile of the annual distribution of the daily maximum 1-hour 
values. Similarly, another commenter suggested use of the highest 
possible concentration as being the most conservative value.
    Response: These comments regarding the limitations in the amount of 
meteorological data used in support of the proposed rule relate to the 
issue of whether the Portland emissions may interfere with maintenance 
of the NAAQS due to variability of meteorological conditions.\15\ 
Although we are not able to explicitly account for the impact of year-
to-year variability of meteorology on downwind modeled concentrations, 
the form of the 1-hour SO2 NAAQS based on the 99th 
percentile of the annual distribution of daily maximum 1-hour values, 
averaged across 3 years for monitoring data, is recognized as a more 
stable metric of ambient air quality that is less sensitive to 
meteorological variability than a deterministic standard that would be 
based on allowing one exceedance per year. For a deterministic 
standard, the inclusion of additional years of meteorological data can 
only increase the modeled design value or leave it unchanged, since the 
design value is the highest of the second-highest values across each of 
the individual years modeled. In contrast, the inclusion of additional 
years of meteorological data for a probabilistic standard such as the 
1-hour SO2 NAAQS may increase or decrease the modeled design 
value since it is averaged across the number of years modeled at each 
modeled receptor.
---------------------------------------------------------------------------

    \15\ The use of 1 year of site-specific meteorological data 
fulfills the requirements of Appendix W related modeling 
demonstrations of compliance with the NAAQS. The commenters are 
addressing the issue of interference with maintenance.
---------------------------------------------------------------------------

    To further illustrate this point, the EPA performed an analysis of 
impacts from Portland based on 5 years of meteorological data from the 
Allentown National Weather Service (NWS) station for the period 2006 
through 2010. This analysis shows that the range of variability between 
the individual year with the lowest modeled design value and the 5-year 
average modeled design value is about 6 percent. For comparison, using 
the same 5 years of meteorology data, the range of variability across 
the 5 years for a deterministic 1-hour standard was about 35 percent 
for the first highest 1-hour values and about 17 percent for the 
highest second-highest 1-hour values. More details regarding these 
analyses are provided in the final rule Modeling TSD.
    We also note that variability in relation to interference with 
maintenance also encompasses variability in emissions. As noted above, 
the modeling conducted to determine the proposed remedy for Portland 
was based on maximum allowable emissions. Since these are the highest 
emissions that are allowed to be emitted by the facility, higher 
concentrations could not be expected to occur in New Jersey due to the 
variability of emissions from Portland. Furthermore, analysis of 
continuous emissions monitoring systems (CEMS) data for Portland 
indicates a much larger range of potential variability associated with 
emissions than was found for meteorological variability based on the 
analysis summarized above.
    Regarding variability in relation to emissions from other sources 
of SO2 that might overlap with impacts from Portland, we 
believe that we have adequately addressed this aspect of variability 
associated with emissions from existing sources through the inclusion 
of a relatively conservative monitored background concentration in the 
cumulative modeling analysis, as discussed in more below in section 
IV.B.4. Furthermore, background ambient concentrations of 
SO2 due to existing sources are likely to decline from 
recent and current levels over the next several years in association 
with the development and promulgation of SIPs for the 1-hour 
SO2 NAAQS as well as the recent finalization of the Cross 
State Air Pollution Rule (CSAPR), also known as the Transport Rule. We 
also note that potential variability, more specifically increases, in 
emissions from new or modified sources would be addressed through the 
new source review (NSR) and prevention of significant deterioration 
(PSD) permitting process associated with implementation of the 1-hour 
SO2 NAAQS.
    Based on these considerations and supporting analyses using 5 years 
of NWS meteorological data, the EPA believes that the modeled design 
value based on the form of the 1-hour SO2 NAAQS is the 
appropriate metric for use in this final rule and that the proposed 
remedy will be adequate to address Portland's significant contribution 
to nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey.

[[Page 69062]]

3. Emissions and Source Characteristics
    Comment: GenOn commented that EPA's dispersion modeling used 
outdated stack parameters for units 1, 2, and 5 and submitted a list of 
revised parameters that it states should be used in the modeling.
    Response: The EPA updated the stack parameters used in the final 
rule dispersion modeling, based on the submitted parameters from GenOn. 
The parameters include the stack heights, exit temperatures, exit 
velocities, and stack diameters. These updated stack parameters had a 
negligible effect on the modeled concentrations. See section IV.A for a 
table of the stack parameters used in the final rule modeling.
    Comment: GenOn commented that interim and final SO2 
emissions limits should only be set for Portland units 1 and 2.
    Response: The EPA agrees that interim and final SO2 
emissions are only needed for Portland units 1 and 2.
    There were no comments supporting emissions limits for the smaller 
sources (units 3, 4, 5, and an auxiliary boiler) in the final rule. In 
fact, in both the original section 126 petition modeling and additional 
modeling submitted as comments on the proposal, NJDEP only included 
emissions from Portland units 1 and 2. In the final rule, the EPA is 
setting emissions limits for units 1 and 2 only.
4. Identification of Background Concentrations
    As noted above in the summary of the EPA modeling for the proposed 
rule, and explained in more detail in the proposed rule Air Quality 
Modeling TSD, the EPA used background concentrations that varied by 
season and hour-of-day based on the 3-year average of the 99th 
percentile of the distribution of hourly SO2 concentrations 
from the Chester, New Jersey, ambient monitor, located about 34 
kilometers southeast of Portland, which represents the high end of the 
distribution of monitored background concentrations in the area.
    Comment: GenOn submitted comments suggesting that the background 
concentrations used in the EPA modeling for the proposed rule based on 
the Chester, New Jersey, monitor were too high and likely included 
impacts from Portland emissions. GenOn also submitted revised 
background concentrations that were adjusted to remove hours for which 
Portland was potentially influencing the Chester, New Jersey, monitor, 
although GenOn did not provide any details regarding the methodology 
used for adjusting the monitored concentrations.
    Response: As noted above in relation to comments on the 
meteorological data, incorporating background concentrations based on 3 
years of monitoring data incorporates some elements of meteorological 
variability into the cumulative modeling demonstration, which further 
mitigates potential concerns regarding reliance on a single year of 
meteorological data in the dispersion modeling. Also, as demonstrated 
by NJDEP's trajectory analysis (NJDEP, July 30, 2010), we agree that it 
is likely that SO2 impacts from Portland contributed to some 
of the high monitored concentrations at the Chester, New Jersey, 
monitor used to represent the background concentrations. Although use 
of the 99th percentile values by season and hour-of-day from the 
Chester monitor excluded some of the peak hourly SO2 
concentrations, the background concentrations are still likely to be 
somewhat conservative (high), but the EPA believes that this 
conservatism is appropriate in order to account for both meteorological 
variability that otherwise could not be explicitly accounted for, and 
low background levels from other sources that may contribute to ambient 
SO2 levels in New Jersey. Furthermore, the differences 
between the background concentrations used in the EPA modeling analysis 
and the background concentrations submitted by GenOn were less than 
about 5 parts per billion (ppb) in most cases, and would have a 
negligible impact of about 0.5 percent on the remedy necessary to 
eliminate Portland's significant contribution to nonattainment and 
interference with maintenance of the 1-hour SO2 NAAQS in New 
Jersey.
5. Columbia Monitor Data and Analyses
    As noted in the proposal, the Columbia air quality monitor in 
Warren County, New Jersey, is located approximately 1.2 miles (about 2 
kilometers) northeast of Portland. The Columbia monitor has recorded 
concentrations over the 75 ppb 1-hour SO2 NAAQS.\16\ See 76 
FR 19662. Since the monitor began operation on September 23, 2010, it 
has recorded numerous exceedances of the 1-hour SO2 NAAQS. 
We noted in the proposal that exceedances of the NAAQS occurred when 
prevailing winds in the area came from the direction of Portland, NJDEP 
submitted a document dated March 4, 2011 titled, ``Analysis of the 
Sulfur Dioxide Measurements from the Columbia Lake NJ Monitor which can 
be found in the docket, (See Docket ID EPA-HQ-OAR-2011-0081-0019). This 
document used wind trajectory analyses to find that Portland's units 1 
and 2 were the likely cause of each high SO2 episode at the 
monitor. We found these analyses to be consistent with our finding and 
modeling which predicts exceedances of the 1-hour SO2 NAAQS 
in the vicinity of the Columbia monitor.
---------------------------------------------------------------------------

    \16\ See ``Summary of 1-Hour SO2 Monitoring Data from 
the Columbia Monitor in Warren County, New Jersey'' TSD available in 
the docket, available in Docket ID EPA-HQ-OAR-2011-0081-0005.
---------------------------------------------------------------------------

    Comment: NJDEP submitted new SO2 ambient data collected 
at the Columbia monitoring station located in Warren County, New 
Jersey. The monitor began collecting data on September 23, 2010, and 
measured exceedances of the 1-hour SO2 NAAQS on 9 days 
through February 17, 2011. The NJDEP submitted a trajectory analysis 
which attempts to track the SO2 emissions from Portland on 
days when exceedances were measured at the Columbia monitor. The NJDEP 
also submitted a new modeling analysis which attempted to model the 
impact of emissions from Portland at the Columbia monitor, using recent 
SO2 CEMS emissions data from Portland and the Columbia 
ambient monitoring data. The NJDEP concludes that the monitoring data, 
trajectory analysis, and the modeling analysis support the EPA's 
proposed finding that Portland significantly contributes to 
nonattainment in New Jersey and is also consistent with the results of 
NJDEP's and the EPA's modeling analyses, showing a good correlation 
between the modeling analyses and monitoring data.
    Response: The EPA agrees with many aspects of the analysis 
submitted by NJDEP. We agree that the trajectory analysis of the recent 
Columbia monitoring data supports the conclusion that the exceedances 
are primarily caused by emissions from Portland. The analysis shows 
that on the days examined, the winds are blowing from Portland towards 
the Columbia monitor, and the available CEMS data show large 
SO2 emissions from Portland.\17\
---------------------------------------------------------------------------

    \17\ The NJDEP analysis also includes CEMS data from the nearby 
Martins Creek power plant which shows little or no SO2 
emissions from Martins Creek on the exceedance days examined.
---------------------------------------------------------------------------

    The EPA also agrees that the modeling analysis submitted by NJDEP 
indicates good performance for AERMOD in representing the modeled 
concentrations at the Columbia monitor on the exceedance days in 2010. 
However, interpretation of the analysis is complicated by the fact that 
concurrent site-specific meteorology is not available during 2010 or 
2011. The

[[Page 69063]]

modeling analysis was therefore conducted with the 1993-1994 site-
specific meteorology used for the proposed rule modeling which as noted 
above the EPA found to be a reasonable assumption. NJDEP used three 
different emissions assumptions in the modeling analysis. It concluded 
that AERMOD modeling based on allowable emissions gives the best 
agreement with monitored concentrations at Columbia. Since the CEMS 
data show that Portland was operating well below allowable emissions 
during many of these exceedances, NJDEP contends that this implies that 
AERMOD is underestimating the modeled concentrations at the Columbia 
monitor. The EPA disagrees with this conclusion. As shown above in our 
response to comments regarding the use of CALPUFF versus AERMOD, we 
believe that the manner in which NJDEP ran AERMOD for this analysis 
contributed to the model underestimating concentrations in the vicinity 
of the Columbia monitor. Specifically, the use of the Portland site-
specific meteorological data without the adjustments incorporated in 
the EPA AERMOD modeling analysis contributes to underestimating impacts 
in the vicinity of the Columbia monitor. Further details regarding the 
EPA analysis of the Columbia monitor are contained in the final rule 
Modeling TSD.

C. Modeling and Other Analyses To Determine Significant Contribution 
for the Final Rule

    The EPA continues to believe that the AERMOD modeling analysis 
provides a more appropriate technical basis for this petition than the 
modeling submitted based on the CALPUFF model, as explained in this 
notice and in more detail in the final rule Modeling TSD.
    The EPA's review of the NJDEP AERMOD analysis supports a finding 
that SO2 emissions contribute significantly to nonattainment 
and interfere with maintenance of the 1-hour SO2 NAAQS. 
However, we noted some technical concerns with the NJDEP modeling which 
may affect the degree to which emissions need to be reduced to be able 
to meet the 1-hour SO2 NAAQS in New Jersey. Therefore, the 
EPA conducted an independent modeling assessment to confirm the finding 
of significant contribution and to help determine the necessary and 
appropriate emission limits for Portland units 1 and 2 (the EPA 
modeling analysis is described in more detail in section V and the 
final rule Modeling TSD).
    As part of the original petition, NJDEP also submitted a trajectory 
analysis of two particular episodes showing that elevated 1-hour 
SO2 measurements at the Chester monitor in Morris County, 
New Jersey, were caused primarily by Portland. As described earlier, 
NJDEP also submitted an analysis (dated March 4, 2011) of recent 
SO2 monitor data at the Columbia monitor in New Jersey, 
which includes a trajectory analysis for exceedance days \18\ at the 
Columbia monitor and a modeling analysis of the impact of Portland 
SO2 emissions on the Columbia monitor.
---------------------------------------------------------------------------

    \18\ When the report was submitted, there were 9 days that 
exceeded the 1-hour SO2 NAAQS, as of February 17, 2011. 
More recent data (downloaded from the NJDEP Web site at http://www.njaqinow.net/Default.aspx) show that there have been 22 
additional 1-hour SO2 exceedance days at the Columbia 
monitor between February 18 and August 20, 2011.
---------------------------------------------------------------------------

    For the reasons discussed above, the EPA believes that the AERMOD 
analysis, submitted by NJDEP and modeled by the EPA, provides a 
reasonable basis for making a finding that emissions from Portland 
significantly contribute to nonattainment and interfere with 
maintenance in New Jersey and for quantifying the SO2 
emissions reductions needed to establish the final remedy emission 
limits. In addition, the trajectory analysis, monitoring data analysis, 
and the air quality monitoring data collected from the Columbia monitor 
in New Jersey are consistent with our finding of significant 
contribution to nonattainment and interference with maintenance of the 
1-hour SO2 NAAQS in New Jersey. Our analysis for determining 
the final emission limits are presented in the next section.

V. Establishing the Emission Limits Necessary for the Remedy

    In the proposed rule, the EPA conducted analyses to determine the 
emissions limits that would be necessary to permit Portland's continued 
operation under our section 126 finding. This section summarizes these 
analyses and discusses the comments and responses on the analyses, and 
our use of the analyses to establish the final remedy. It also 
discusses the selection of the appropriate time frame for the final 
remedy, as well as other issues that commenters raised concerning the 
final remedy. Continued operation of a major existing source subject to 
a section 126 finding is permitted only if the source complies with 
emission limits and compliance schedules established by the EPA to 
bring about compliance with the requirements in sections 
110(a)(2)(D)(i) and 126 as expeditiously as practicable, but in no case 
later than 3 years after the effective date of the finding. Thus, to 
determine the appropriate remedy, the EPA must quantify the reductions 
necessary to eliminate Portland's significant contribution to 
nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey.

A. Quantification of Necessary Emissions Reductions

    To calculate emissions reductions necessary to eliminate Portland's 
significant contribution to nonattainment and interference with 
maintenance of the 1-hour SO2 NAAQS in New Jersey for the 
proposed rule remedy, the EPA completed AERMOD modeling of Portland 
units 1, 2, and 5 using the 1993-1994 Portland site-specific 
meteorological data.\19\ As detailed in section IV, the EPA continues 
to believe that AERMOD is the appropriate model to make a finding that 
emissions from Portland contribute significantly to nonattainment or 
interfere with maintenance, and to calculate the appropriate emission 
limits for Portland units 1 and 2. In applying AERMOD to establish the 
remedy for the proposed rule, the EPA made several adjustments to the 
meteorological inputs (compared to the NJDEP modeling) which it 
determined to be appropriate. As described in Section IV above, the EPA 
continues to believe the meteorological data and model setup 
modifications are appropriate and we are continuing to use the same 
modifications for the final rule AERMOD modeling. The EPA remedy 
modeling also includes background concentrations that vary by season 
and hour of day based on the 99th percentile ambient data from the 
Chester, New Jersey SO2 monitor. The EPA believes the 
background concentration methodology to be reasonable and appropriately 
conservative, and is using this methodology in the final rule modeling.
---------------------------------------------------------------------------

    \19\ For completeness, the EPA included emissions from Portland 
unit 5 in the final rule dispersion modeling (but did not propose or 
finalize a revised emissions limit for unit 5). The unit 5 emissions 
were included in the analysis to verify that they did not impact the 
calculation of the final emissions limit. Due to our understanding 
that the other emissions sources (units 3, 4, and an auxiliary 
boiler) at Portland have negligible or zero SO2 
emissions, the EPA did not include those sources in the final rule 
modeling.
---------------------------------------------------------------------------

    The EPA AERMOD analysis used allowable SO2 emissions 
rates for Portland units 1, 2, and 5 long with stack parameters 
submitted by GenOn shown in Table V.A-1:

[[Page 69064]]



                                                   Table V.A-1
----------------------------------------------------------------------------------------------------------------
                                              Permitted                     Stack         Stack         Stack
                  Source                      emission    Stack height    diameter     temperature  velocity  (m/
                                             rate  (g/s)       (m)           (m)           (K)           s)
----------------------------------------------------------------------------------------------------------------
Portland Coal Unit 1......................        733.3         121.31          3.15        418.1          32.86
Portland Coal Unit 2......................      1,121.0         121.82          3.84        406.0          34.19
Portland Turbine 5........................         12.0          42.67          6.10        821.5          36.60
----------------------------------------------------------------------------------------------------------------

    The location of maximum SO2 concentration impacts from 
Portland emissions were found to occur in a similar location as in the 
proposal modeling. Therefore, the same 100 meter receptor fine grid 
modeling domains were used in the final rule modeling. The controlling 
modeled design value impact from Portland in New Jersey based on the 
EPA's final rule modeling was 855.4 ug/m\3\ which is the basis for 
quantifying the necessary emission reductions. This included a 
contribution from Portland units 1 and 2 of 815.0 ug/m\3\, a monitored 
background concentration of 39.3 ug/m\3\, plus a contribution of 1.1 
ug/m\3\ from Portland unit 5. See the final rule Modeling TSD for more 
information on the AERMOD setup and modeling results.

B. Summary of the EPA's Proposed Remedy Analysis

    In the proposed rule, the EPA calculated the emissions reduction 
needed to eliminate Portland's significant contribution to 
nonattainment based on the maximum modeled design value concentration 
in New Jersey. If the modeled concentration from Portland plus 
background is reduced to a level that is below the 1-hour 
SO2 NAAQS, then all modeled violations of the NAAQS in New 
Jersey are eliminated. For the proposed rule, the emissions reduction 
needed to eliminate all modeled violations in New Jersey was used to 
define the elimination of significant contribution to nonattainment and 
interference with maintenance.
    Based on the EPA modeling results, the EPA proposed that an 81 
percent reduction in allowable SO2 emissions from Portland 
units 1 and 2 was needed to reduce the Portland contribution plus 
background to below the NAAQS.
    The EPA also evaluated the modeling results to determine if an 
emission limit could be set that combined the total emissions at units 
1 and 2. In the proposal, the EPA determined that there are many 
different combinations of emissions limits for units 1 and 2 that could 
eliminate violations of the SO2 NAAQS in New Jersey. 
However, the stack parameters (exit velocity and stack diameter) of 
units 1 and 2 are slightly different, which causes the maximum downwind 
impacts from each unit to occur at slightly different locations and at 
different times. In addition, the EPA proposed that Portland can comply 
with the emissions limits in several different ways (e.g., low sulfur 
coal, reduced operation of one or both units, and/or installation of 
post-combustion controls). Given all of the possible compliance options 
and interactions between the plumes from units 1 and 2, we were not 
able to effectively examine multiple compliance strategies for the 
proposal. Therefore, we proposed emissions limits based on an 81 
percent reduction in allowable emissions at both units 1 and 2. This 
led to a proposed SO2 emissions limit for unit 1 of 1,105 
lb/hr (allowable emission rate of 5,820 lb/hr*0.19 [an 81 percent 
reduction]) and a proposed SO2 emissions limit for unit 2 of 
1,691 lb/hr (allowable emission rate of 8,900 lb/hr*0.19 [an 81 percent 
reduction]).

C. Summary of Comments and Responses Regarding the Remedy Modeling

    Comment: One commenter noted that various methods to comply with an 
emissions limit (such as installation of a control device) may affect 
stack parameters such as exit temperature and exit velocity, which may 
affect the dispersion of emissions and downwind concentrations. The 
emissions limit was calculated using a simple ``rollback'' calculation 
which assumes that concentrations will be reduced in proportion to 
emissions.
    Response: We agree with commenters that it is likely (though 
unknown at this time) that the strategy to comply with the final rule 
emissions limits will cause changes in stack parameters for units 1 and 
2. In addition, we agree that this should be accounted for, but in the 
proposed rule, the EPA did not take into account the effect of 
operating load on stack parameters. The exit velocity is reduced when 
the plant is operating below full load. Based on information submitted 
by GenOn as part of its comments, the exit velocity could be reduced by 
as much as 50 percent when operating at or below 50 percent operating 
load (defined as percent of maximum heat input for each unit). To 
account for potential reduced plume rise and dispersion due to reduced 
load or control devices, the EPA ran several AERMOD sensitivity runs. 
We simulated the proposed remedy emissions rate for units 1 and 2 
(1,105 lb/hr unit 1 limit and 1,691 lb/hr unit 2 limit) at 100 percent 
load, which resulted in a maximum design value concentration of 193.7 
ug/m3 (which is below the 196.2 ug/m3 1-hour SO2 NAAQS). We 
then ran AERMOD with the same emissions rates, but at reduced loads of 
75 percent, 50 percent, and 25 percent. The exit velocity for the 
reduced load runs was reduced based on information submitted by GenOn. 
The reduced exit velocity led to reduced plume rise and dispersion and 
higher downwind maximum concentration impacts. The maximum 
concentrations at 75 percent, 50 percent, and 25 percent load were 
227.3 ug/m\3\, 264.3 ug/m\3\, and 300.3 ug/m\3\, respectively. These 
impacts all exceed the 1-hour SO2 NAAQS. See the final rule 
Modeling TSD for more details on the sensitivity analysis.
    In the final rule, the EPA will ensure that the NAAQS is protected 
(and therefore that significant contribution to nonattainment and 
interference with maintenance is eliminated) in two ways. First, in 
addition to the lb/hr emissions limit for each unit, we are finalizing 
a lb/mmBtu emissions limit to address modeled exceedances at reduced 
load. The lb/mmBtu limit is determined based on an equivalent lb/hr 
limit at 100 percent load for each unit. Meeting a lb/mmBtu will 
therefore have the effect of lowering the resulting lb/hr emissions 
rates at reduced loads. For example, emissions will be 25 percent lower 
than the lb/hr limit when operating at 75 percent load. This in turn 
will ensure that the NAAQS is protected at reduced loads. Modeling of 
emissions rates that are constrained by a lb/mmBtu limit shows that 
concentration impacts at reduced loads are always less than maximum 
concentrations at 100 percent load. See section VI for more details on 
the calculation of lb/mmBtu limits.
    The second way that we are ensuring that the remedy will be 
protective of the

[[Page 69065]]

NAAQS is by requiring GenOn, as part of the increments of progress 
requirements, to submit a modeling protocol and dispersion modeling 
analysis of its final compliance strategy. GenOn will be required to 
show that the final remedy, as actually implemented, including any 
changes to stack parameters that may have resulted from steps taken to 
meet the limits, will be protective of the NAAQS and therefore 
eliminate significant contribution to nonattainment and interference 
with maintenance in New Jersey. See section VI for more details on the 
increments of progress requirements and schedules.
    Comment: One commenter (GenOn) urged the EPA to set a combined 
emission limit for units 1 and 2 for both the interim limits and the 
final limits. GenOn submitted a modeling analysis which examined the 
effects of various permutations of the proposed interim limit. The 
commenter ran an AERMOD ``reference run'' with the proposed interim 
limit of a 50 percent reduction in allowable emissions at both units 1 
and 2 (a total of 7,360 lb/hr). GenOn then ran two additional 
``sensitivity'' runs; one with unit 1 running at its full allowable 
limit (5,820 lb/hr) and unit 2 at zero emissions and a third model run 
with unit 1 at zero emissions and unit 2 at 7,360 lb/hr (the combined 
limit at a 50 percent reduction from allowables). The results show that 
maximum design value concentrations from the sensitivity runs are less 
than the reference run. Therefore, GenOn argues that a combined limit 
will provide for air quality impacts that are equivalent to or better 
than the proposed individual unit limits.
    Response: The EPA agrees that the operating scenarios that were 
modeled show that a combined limit can lead to air quality impacts that 
are equivalent to or better than individual limits. However, that is 
not true in all cases, particularly for the final emissions limits. For 
example, the EPA modeled the combined proposed remedy emission limits 
(2,796 lb/hr) individually at unit 1 and unit 2. Emitting 2,796 lb/hr 
from unit 2 (with no emissions from unit 1) was protective of the NAAQS 
(design value of 189.1 ug/m\3\ at 100 percent load). However, emitting 
2,796 lb/hr from unit 1 (with no emissions from unit 2) led to modeled 
violations at 100 percent load (225.2 ug/m\3\). Due to the slightly 
different stack parameters of each unit, more emissions can be emitted 
through unit 2 without leading to a violation, compared to unit 1. 
Therefore, a combined emissions limit that is emitted completely from 
unit 1 is not protective of the NAAQS.
    For this reason, based on the modeling analysis conducted by the 
EPA, we are not able to set a combined limit for the final remedy. (We 
discuss the separate question of a combined limit for the interim limit 
in section VII.) The final rule contains individual final limits that 
are specific to units 1 and 2. It is also clear from this simple 
analysis that any combined limit that would still be protective of the 
NAAQS across the full range of operating scenarios for units 1 and 2 
and would necessarily be more restrictive than the 81 percent reduction 
on each of units 1 and 2. There are some combinations of emissions from 
units 1 and 2 which will be protective of the NAAQS and some that will 
not. The EPA is not able to model all possible combinations and then 
set a combined limit which is protective of the NAAQS in all cases. 
Should GenOn wish to have a higher limit at one of the units, in 
exchange for a lower limit at the other, or seek a combined limit that 
is protective of the NAAQS in all cases, there is an opportunity to 
petition the EPA for additional rulemaking to adopt alternative 
emissions limits, although we note that such rulemaking would require a 
notice and comment process. Further details are contained in section 
VII later.
    Comment: NJDEP recommended that the final rule should require a 95 
percent reduction to be phased in as soon as possible, in a time period 
shorter than 3 years. In support of these recommendations, NJDEP also 
noted that power plants in New Jersey will be required to achieve an 
emission rate of 0.150 lb/mmBtu by December 15, 2012, and that two 
facilities in New Jersey are already meeting this level.
    Response: We note that section 126 does not give the Administrator 
discretion to establish emission limitations beyond the emission 
reduction necessary to eliminate Portland's significant contribution to 
nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey. Sections IV and V discuss comments 
on the appropriate air quality models, and modeling assumptions, data 
and results, and their effect on the choice of the specific limits for 
Portland units 1 and 2.
    Comment: The EPA received numerous comments generally noting the 
adverse health and environmental effects of SO2 emissions 
and urging significant emission reductions of SO2 from 
Portland, providing examples of the beneficial effects that would occur 
by reducing SO2 emissions and, for these reasons, urging 
significant reductions.
    Response: The EPA recognizes that there are potentially adverse 
health impacts from breathing SO2 particularly for people 
who have respiratory illnesses, heart, or lung disease, older adults 
and children, and that SO2 is a precursor to acid rain 
formation and fine sulfate particle formation that can also pose 
adverse health effects. These effects are taken into account in 
establishing the SO2 NAAQS, and need not be revisited in 
this action. Therefore, this rule is directed at eliminating Portland's 
significant contribution to nonattainment and interference with 
maintenance of the 1-hour SO2 NAAQS in the affected areas of 
New Jersey. Elsewhere in this section, we explain how we are using 
modeling to assure that we are establishing a remedy that eliminates 
significant contribution and results in emissions limits that are 
protective of the NAAQS.

D. The Final Remedy Limit

    The EPA modeled a scenario using allowable emissions from Portland 
with 1 year of site-specific meteorological data. The maximum modeled 
1-hour SO2 design value in New Jersey was 855.4 ug/m\3\. 
This included a contribution from Portland units 1 and 2 of 815.0 ug/
m\3\, a monitored background concentration of 39.3 ug/m\3\, plus a 
contribution of 1.1 ug/m\3\ from Portland unit 5. The final compliance 
emission limits must be set at a level that eliminates all violations 
of the 1-hour SO2 NAAQS in New Jersey. Therefore, all 
modeled receptors must be below the level of the NAAQS (196.2 ug/m\3\). 
The contribution from Portland can be reduced by reducing the 
SO2 emissions from the Portland stacks, but the background 
concentrations cannot be reduced (they are held constant). Since the 
contribution from unit 5 is only 0.1 percent of the total contribution, 
a reduction in the unit 5 contribution would provide a negligible 
reduction to the modeled design value. Therefore, it can be assumed 
that unit 5 emissions do not need to be reduced, and the unit 5 
concentration is added to the irreducible background value. The final 
compliance emission limit for the final rule is calculated as follows: 
((Total modeled concentration)--(NAAQS--background))/(total modeled 
concentration).This formula will produce the percentage by which 
Portland must reduce its emissions from allowables in order to achieve 
compliance with the NAAQS in New Jersey. Thus, the actual calculation 
of Portland's contribution to nonattainment in New Jersey is ((814.9)-
(196.2-40.4))/814.9, where 40.4 represents the contributions from

[[Page 69066]]

monitored background and unit 5. This results in a reduction of 80.9 
percent of allowable emissions from Portland units 1 and 2, which we 
round to 81 percent. In this calculation, only the contribution from 
units 1 and 2 is included in the total modeled contribution.
    Therefore, we are finalizing an emissions limit based on an 81 
percent reduction in allowable emissions at both units 1 and 2. This 
leads to a final SO2 emissions limit for unit 1 of 1,105 lb/
hr (allowable emissions rate of 5,820 lb/hr*0.19 [an 81 percent 
reduction]) and a final SO2 emissions limit for unit 2 of 
1,691 lb/hr (allowable emissions rate of 8900 lb/hr*0.19 [an 81 percent 
reduction]), which are the same as the proposed limits.
    As discussed earlier in response to a comment, to account for 
operation at less than 100 percent load and/or changes in stack 
parameters, the EPA is also setting a lb/mmBtu emissions limit for 
units 1 and 2 in the final remedy. To determine the level, we 
calculated the lb/mmBtu value as the emissions rate that equates to the 
lb/hr limits for unit 1 and 2 when operating at full load. That is, for 
unit 1 the lb/mmBtu limit is calculated as the lb/hour limit of 1,105 
lb/hour divided by the heat input capacity of 1,657.2 mmBtu/hr, which 
equates to 0.67 lb/mmBtu. For unit 2, the lb/hour limit of 1,691 lb/
hour is divided by the heat input capacity \20\ of 2511.6 mmBtu/hr also 
results in 0.67 lb/mmBtu.
---------------------------------------------------------------------------

    \20\ Heat input capacities were from the Title V Permit No. 48-
0006.
---------------------------------------------------------------------------

    Compliance with the 0.67 lb/mmBtu limitation is determined on a 30 
boiler operating day rolling average basis. A ``rolling'' average means 
that a new 30-day average can be determined on any day of operation. 
Similar to the proposed Mercury and Air Toxics Standards (MATS) rule, 
the EPA clarifies that only the hours on ``boiler operating days'' are 
included in the averaging, and the 30-day averaging ``zero values'' 
from non-operating days are not included. We use the same definition of 
``boiler operating day'' as for the proposed MATS; that is, a 24-hour 
period between midnight and the following midnight during which any 
fuel is combusted in the units. The EPA recognizes that a 30-day 
averaging period for the lb/mmBtu limitation incorporates some 
variability, and that there will be hourly periods that exceed the 30-
day average.
    The EPA does not believe that these higher hourly values would lead 
to exceedances of the NAAQS for a number of reasons. First, at full or 
near-full load, compliance with the lb/hour limit will ensure emissions 
rates at or near 0.67 lb/mmBtu. Second, at significantly lower loads, 
Portland units 1 and 2 could emit at emissions rates somewhat greater 
than 0.67 lb/mmBtu and still meet the NAAQS. Accordingly, some 
variability within the 30-day averaging is accommodated, although the 
EPA expects the variability will be relatively small. For example, 
during 2010 the emission rate for Portland varied by only about 15 
percent.
    As a final check on the remedy, EPA ran AERMOD again with the above 
emissions limits on the Portland Plant's units 1 and 2 (and current 
allowable emissions from unit 5). At these emissions levels, all 
receptors in New Jersey had concentrations below the 1-hour 
SO2 NAAQS. The maximum modeled 99th percentile (4th-highest) 
daily maximum 1-hour SO2 concentration was 193.7 ug/m \3\ 
(including a monitored background concentration of 39.3 ug/m \3\).

E. Compliance Schedule for the Final Remedy Limit

    Section 126(c) initially makes it unlawful for any major existing 
source to operate more than 3 months after a section 126 finding has 
been made with respect to it; yet also gives the Administrator 
authority to permit continued operation under certain conditions. 
Specifically, the statute provides that the Administrator ``may permit 
the continued operation'' of such a source beyond the end of the 3 
month period ``if such source complies with such emission limitations 
and compliance schedules (including increments of progress) as may be 
provided by the Administrator to bring about compliance with the 
requirements contained in section 7410(a)(2)(D)(i) of this title or 
this section as expeditiously as practicable, but in no case later than 
3 years after the date of such finding.'' 72 U.S.C. 7426(c).
    Section 126, however, does not give the Administrator unlimited 
discretion when establishing emission limitations and compliance 
schedules. Instead, the statute provides that the emission limitations 
and compliance schedules must bring about compliance with the 
requirements of section 110(a)(2)(D)(i) of the Act ``as expeditiously 
as practicable'' but in no case later than 3 years from the date of the 
finding. The use of the phrase ``as expeditiously as practicable'' 
allows for consideration of the time needed to implement a compliance 
option in setting a compliance schedule. However, the length of time 
needed to implement any given compliance option depends on the 
particular compliance option to be implemented. Furthermore, the EPA 
recognizes that in some instances a source may choose to cease 
operation as its method of compliance. In the proposed rule, the EPA 
requested comment on the meaning of as ``expeditious as practicable'' 
in this context.
1. Proposed Compliance Schedule
    The EPA proposed to allow continued operation of Portland beyond 3 
months provided that the facility operates in compliance with final 
emission limits within 3 years and with interim emission limits and 
procedural increments of progress. In this section we discuss our 
response to comments on the appropriateness of a 3-year deadline for 
the final limits (See section VI.A. below for further discussion of 
interim limits and other increments of progress).
2. Public Comments and the EPA's Responses
    In the proposal, the EPA recognized both that the statute requires 
that any compliance schedule ensure compliance ``as expeditiously as 
practicable'' and also that, while the statute directs the EPA to 
establish emission limits and compliance schedules, it does not 
foreclose the EPA from allowing the source to select a compliance 
option. In the proposal, the EPA noted its desire to seek a balance 
between the statutory requirement of compliance ``as expeditiously as 
practicable'' and the goal of ensuring that the regulation does not 
unnecessarily limit the options available to the source to achieve 
compliance within the statutorily mandated time period. The EPA did not 
receive any comments specifically challenging the EPA's balanced 
approach to interpreting the statutory language. Accordingly, the EPA's 
final remedy in this rulemaking has been developed consistent with 
these goals.
    Comment: The EPA received a general comment comparing the ``as 
expeditiously as practicable'' language in section 126 to our 
interpretation of that language in the MATS rule. The commenter 
suggests that we should always interpret ``as expeditiously as 
practicable'' to mean 3 years.
    Response: While the EPA is permitting 3 years in this case, the 
commenter's interpretation is inconsistent with the language of section 
126 because, by saying ``in no case later than 3 years,'' the statute 
contemplates that compliance might be required sooner than 3 years.
    The EPA also received a number of specific comments on technical 
feasibility issues and other issues

[[Page 69067]]

related to the 3-year compliance period for the final remedy. A number 
of commenters believed that a 3-year period was too generous and that 
Portland units 1 and 2 should achieve needed emissions reductions in a 
shorter time period. Other commenters questioned the feasibility of 
meeting the limits within 3 years and recommended that the EPA should 
harmonize the requirements of this rule with those of other rules 
regulating electric generating units (EGUs). The following sections 
discuss EPA's responses to the comments in each of these issue 
categories.
a. Technical Feasibility
    Comment: Several commenters objected to the 3-year compliance 
period and recommend an abbreviated compliance schedule or a schedule 
that requires compliance with the final limits in less than a year. 
Some commenters believed that technologies necessary to achieve the 
emission reductions could be installed and operating within 1 year (for 
example, dry sorbent injection or DSI) or 2 years (dry scrubbing). 
Others cited the availability of very low sulfur coal, such as sub-
bituminous coal from the Powder River Basin (PRB) in Wyoming, asserting 
that emission reductions could be achieved in a shorter time period 
than 3 years. Another commenter noted that the Keystone Generating 
Plant located in Pennsylvania installed a scrubber within 3 years, and 
reduced SO2 emissions by 98 percent. One commenter cited the 
EPA estimates of a 24-27 month time period for dry and wet scrubbing, 
and recommended that we replace the 3-year requirement with a time 
period consistent with those estimates. Other commenters, including 
GenOn, were concerned that the proposed final limits could not be 
achieved within 3 years.
    Response: We believe that 3 years represents an expeditious 
schedule for GenOn to meet the emissions limits for this rule. While we 
are not mandating any particular control technology or approach, the 
EPA believes that GenOn would have a number of possible options, which 
may need to be used in combination, to evaluate for compliance with the 
rule. These options could include, among others: (1) Switching to very 
low sulfur coal as a number of facilities have undertaken as a result 
of the acid rain program and the Clean Air Interstate Rule, (2) 
switching to lower sulfur coal in combination with lower-capital cost 
technologies such as reagent injection of Trona or sodium bicarbonate, 
and (3) continued use of higher-sulfur coal in combination with dry 
scrubbing or wet scrubbing.
    While the first option, switching to very lower sulfur coal such as 
Wyoming Powder River Basin (PRB) coal, may be a possibility for 
Portland, the EPA notes that the type of sub-bituminous coal that would 
be necessary to achieve the final remedy would have markedly different 
fuel and handling characteristics, necessitating changes not only in 
the coal handling and preparation operations but also to the boilers. 
Publications \21\ discussing examples of the design changes 
necessitated by switching from bituminous to PRB coal are included in 
the docket for this rulemaking. The EPA believes that 3 years would be 
a reasonable time period to evaluate and accomplish all of the 
necessary operational changes.
---------------------------------------------------------------------------

    \21\ See B. Exner, et al., Successful NOx Reduction and 
Conversion to Powder River Basin Fuel on Wall Fired Boilers, Foster 
Wheeler (1996), available on the web at: http://www.fwc.com/publications/tech_papers/files/TP_FIRSYS_96_01.pdf, and 
available at Docket ID EPA-HQ-OAR-2011-0081; R. Barnum, et al., 
Fuel-Handling Considerations When Switching to PBR Coals, Power 
(November/December 2001), available on the web at http://www.prbcoals.com/pdf/PRBCoalInformation/PRB-FuelHandling.pdf. and 
available at Docket ID EPA-HQ-OAR-2011-0081.
---------------------------------------------------------------------------

    The EPA believes the second option is available; that is, switching 
to somewhat lower-sulfur coal such as Central Appalachia coal (CAAP) to 
achieve some of the needed reductions, with the remainder of the 
reductions achieved through a reagent injection system achieving 
reductions of 50-60 percent. For the proposed rule, the EPA requested 
comment on its view that such a reagent injection system could be built 
within 1 year. The EPA agrees with comments that observed that, in 
virtually all cases where such reagent injection systems have been 
installed, the facility has also included a fabric filter for 
particulate controls. Accordingly, the EPA agrees with commenters that 
it would take longer than 1 year to accomplish any operational changes 
necessary to switch to somewhat lower sulfur coal, to install and 
operate the reagent injection system, and to install a fabric filter to 
replace or supplement the current particulate controls. Development of 
a system that adequately controls SO2 and maintains 
acceptable levels of PM controls could likely not be achieved within a 
1-year period, and most likely would take considerably longer. At the 
same time, the EPA disagrees with commenters who suggest that there are 
feasibility concerns for compliance within 3 years, the maximum amount 
of time provided for compliance under section 126. There are three 
steps to carrying out this control option: (1) Operational changes 
related to changing the coal supply, including blending, (2) 
construction and operation of the reagent injection system, and (3) 
implementation of any changes necessary to ensure continued 
effectiveness of particulate controls. However, as proposed, we believe 
the first two steps are achievable in 1 year, but construction and 
operation of a fabric filter is also necessary, and this step could 
take up to 2 additional years.
    The third option, under which Portland would install a dry or wet 
scrubber, likely would achieve a greater degree of control than 
necessary to meet the lb/hr and lb/mmBtu limits in this section 126 
rule. The EPA recognizes that given investment decisions for the suite 
of regulations, including the Transport Rule, the present section 126 
rule, and the upcoming MATS rule, Portland may choose to install these 
controls. If this option were selected, the EPA continues to conclude 
that these scrubber controls could be installed within 3 years. 
(Although such controls have been installed in 24-27 months, the EPA 
believes that it is reasonable to provide the full 3 years to permit 
Portland the time needed to evaluate its options.) We note, however, 
that in the Integrated Planning Model (IPM) which was used to evaluate 
the impacts of the Transport Rule, we did not forecast dry or wet 
scrubbing as the least-cost option for compliance for the Portland 
facility. Rather, the IPM predicted a switch to lower-sulfur bituminous 
coal in combination with reagent injection. IPM model results are 
available in the Transport Rule docket at EPA-HQ-OAR-2009-0491-4440 
(http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OAR-2009-0491-
4440), and on the EPA's Web site at http://www.epa.gov/airmarkets/progsregs/epa-ipm/transport.html.
b. Continued Operation of Facility in the Interim Period
    Comment: The NJDEP commented that if significant reductions cannot 
be made expeditiously, Portland should not be allowed to operate, and 
that the burden to justify any operation beyond 90 days should be on 
the Portland facility owners and operators.
    Response: The EPA disagrees with the commenter's recommendation 
that Portland be required to shut down pending implementation of 
emissions controls. Under section 126 of the CAA, the statute permits 
the continued operation if the source complies with emission 
limitations and compliance schedules established by the

[[Page 69068]]

Administrator. The EPA is including emissions limits and compliance 
schedules in this rule sufficient to expeditiously eliminate Portland's 
signification contribution. The EPA does not believe that the statute 
mandates that the source cease operation at the 90-day milestone under 
these circumstances. The statute's explicit recognition that the 
compliance schedules must be ``practicable'' suggests that it is 
reasonable for the Administrator to permit continued operation 
consistent with such compliance schedules and emissions limitations.
c. Harmonization With Other Requirements
    Comment: Some commenters urged the EPA to defer action on the 
section 126 petition to enable the EPA to harmonize the schedule and 
requirements for this rule with requirements of other pending and final 
rules. Those commenters believed that harmonization with these rules, 
including the MATS rule and the Transport Rule, would enable GenOn 
greater opportunity for fully informed investment decisions that take 
into account all of the applicable regulations.
    Response: The EPA is sensitive to the desirability and advantages 
of harmonized regulatory requirements. We understand that Portland's 
actions to address its significant contribution to nonattainment and 
interference with maintenance of the 1-hour SO2 NAAQS are 
occurring in relatively close proximity to actions it may take to 
address its contribution to nonattainment and interference with 
maintenance of the 1997 ozone NAAQS and the 1997 and 2006 
p.m.2.5 NAAQS under the recently-finalized Transport Rule, 
as well as actions it may need to take to address its emissions of 
Hazardous Air Pollutants under the forthcoming MATS rule. We recognize 
the value for GenOn in having the ability to make informed investment 
decisions that optimize strategies for addressing these pollutants 
concurrently.
    The EPA notes that, in contrast to when this rule was initially 
proposed, the final requirements of the Transport Rule are now known. 
Pennsylvania is one of the states whose facilities are subject to the 
Transport Rule which establishes an emissions budget for Pennsylvania, 
allocates allowances to facilities in Pennsylvania, including Portland, 
and allows Portland's owners to trade those allowances with other power 
plants through an allowance trading market. Portland allowances for 
2012 and 2014 are listed in a technical support document to the final 
Transport Rule located at http://epa.gov/airtransport/pdfs/UnitLevelAlloc.pdf. There are, however, a number of differences between 
this rule addressing section 126 of the CAA and the requirements of the 
Transport Rule. First, in addressing NJDEP's section 126 petition 
related to ambient 1-hour SO2, the EPA must ensure that the 
SO2 emissions from Portland do not significantly contribute 
to nonattainment, or interfere with maintenance of the 1-hour ambient 
SO2 standard of 75 ppb, a relatively localized pollutant 
source-oriented, in New Jersey. In contrast, the Transport Rule 
addresses SO2 emissions in the context of downwind 
PM2.5 problems, a highly transported pollutant, in many 
states. As a result, this section 126 rule does not provide for 
emissions trading with other facilities, while the Transport Rule does 
allow for such trading. Second, the schedule for the Transport Rule is 
somewhat different from this rule. Under the Transport Rule, Portland 
must show for 2012 (that is the calendar year January through December) 
and subsequent years that it holds allowances sufficient to cover its 
annual emissions. These requirements for 2012 precede the requirements 
for this section 126 rule, which requires the source to meet interim 
emissions limits within 1 year (early 2013) with 3-year requirements 
taking effect in early 2015. Notwithstanding these differences, which 
stem from the different CAA requirements being addressed, we believe 
that with the finalization of this rule, Portland has the information 
it needs to make an informed decision on how to comply with both rules.
    At this time, the MATS rule is not final. The EPA has proposed the 
MATS rule and is under a consent decree deadline to complete that rule 
by December 16, 2011. The proposed MATS rule contained proposed 
requirements for hazardous air pollutants, including existing sources 
of acid gases (e.g., hydrogen chloride). The MATS rule does not 
directly regulate SO2 but in the proposal the EPA provided 
its assessment that the acid gas requirements of the proposed MATS 
would have substantial SO2 co-benefits. While the date of 
this section 126 rule does not exactly coincide with the date for the 
final MATS, these two rules are expected to take effect within a short 
time of each other. Accordingly, the EPA believes that GenOn will have 
the information it needs to make an informed decision on how to meet 
both this final rule and the MATS.
    Even if the schedules did not coincide so closely, the EPA does not 
believe it would be appropriate to defer action on NJDEP's section 126 
petition to achieve such harmonization. The EPA is required by the CAA 
to take action on NJDEP's petition within 60 days (plus a 6 month 
administrative extension granted in this case), and this time period 
has already passed. We could not delay lawfully this rulemaking by any 
significant time period to coincide with the date for the final MATS 
rule. The EPA also notes that full harmonization is limited by 
statutory constraints. While there is some flexibility within section 
112 of the CAA to provide for a 4-year compliance period under certain 
circumstances, this flexibility is not afforded under section 126. 
Under section 126, the EPA cannot alter the statutory requirement that 
the source eliminate its significant contribution to nonattainment and 
interference with maintenance within 3 years of the section 126(b) 
finding. Notwithstanding these constraints, as previously noted, our 
expectation is that requirements for MATS, like those of the Transport 
Rule, will be known in time to allow for consideration of integrated 
strategies for compliance with MATS, the Transport Rule, and the 
present section 126 action.
The Final Rule
    Based on the above considerations, we are retaining the 3-year 
compliance date for the final limit. Adopting a substantially shorter 
time frame than 3 years could not only restrict the options for 
Portland to achieve the necessary reductions, but could render each of 
them impracticable within that time frame. Because shorter time frames 
have the effect of narrowing the available options, we are retaining 
the 3-year compliance date for the final limit.

F. Other Considerations for Establishing the Final Remedy

1. Economic Feasibility
    Comment: Several commenters stated that the importance of the 
Portland facility to the local economy should be taken into account, 
and that we should not take an action that causes operations at 
Portland units 1 and 2 to be no longer economically viable. These 
commenters contend that there are limits to the costs the facility can 
withstand and remain in operation, and that the facility should be 
allowed to meet interim and final limits in the most cost-effective and 
efficient manner possible. Commenters expressed concerns regarding the 
practicality of expending high costs on scrubber installation 
considering the size and age of the units at Portland, and questioned 
the feasibility of replacing

[[Page 69069]]

Portland units 1 and 2 with comparable combined-cycle natural gas-fired 
units.
    Response: The EPA stresses that in carrying out the statutory 
obligation to address the SO2 exceedances caused by the 
Portland facility, we are doing so in a way that meets those 
obligations but is not overly prescriptive. We allow the facility 
owners to choose the most cost-effective solution. While there are many 
factors, some completely unrelated to this rule, which may impact the 
long-term operation of the facility, the EPA is striving to provide 
opportunities for flexible solutions to address section 126 of the CAA. 
In particular, the rule does not mandate, nor do we expect, the 
Portland owners and operators to install high capital-cost options 
suggested by commenters, such as wet scrubbing or replacement with 
combined-cycle natural gas units (although the rule also does not rule 
them out as options). The source would more likely choose the control 
technology best suited to achieving the required emission limits, 
including the most cost-effective technology for the facility. It is 
also useful to note that in the EPA's IPM modeling of the effects of 
the Transport Rule over a wide region, the model predicted that less 
than 0.5 percent of capacity would be lost as a result of the rule. 
While these models are less reliable in assessing plant-specific 
conditions, the EPA believes that the general indication of minimal 
capacity loss, together with the availability of less capital-intensive 
control options, suggest that Portland can achieve the needed 
reductions without substantially affecting the economic viability of 
the plant.
2. Requirement for Continuous Monitoring
    Comment: One commenter suggested that the EPA should add a 
requirement in the final rule to require Portland to operate CEMS for 
SO2 emissions at the plant.
    Response: The EPA acknowledges the importance of CEMS to ensure 
compliance with emissions limits. However, GenOn is already required to 
operate CEMS to monitor SO2 emissions at Portland in 
accordance with requirements in 40 CFR part 75. Our regulations for 
monitoring SO2 emissions from power plants with CEMS require 
the owner or operator to ensure that all CEMS are in operation and 
monitoring unit emissions at all times the affected unit combusts any 
fuel. Regulations in part 75 provide limited exceptions during periods 
of calibration, quality assurance, or preventative maintenance, but do 
not provide any exemptions for startup, shutdown, or malfunction of the 
combustion unit. The EPA concludes that the CEMS already required for 
Portland under part 75 provide sufficient monitoring for compliance 
determinations for SO2 emissions at Portland, and for the 
final rule we refer to part 75 as the primary method for determining 
compliance.
3. Delegation of Enforcement
    Comment: One commenter suggested enforcement of any emissions 
limits or other restrictions on Portland related to this section 126 
action should be delegated to the NJDEP as New Jersey is the downwind 
receptor of emissions from Portland.
    Response: Ensuring that the Portland facility complies with the 
requirements of the CAA including the provisions of this final rule is 
the responsibility of the EPA. It will ultimately become the joint 
responsibility of the EPA and of the Pennsylvania Department of 
Environmental Protection (PADEP), because PADEP has primary 
responsibility for implementing and enforcing the Pennsylvania SIP. The 
EPA notes that CAA section 110(a)(2)(D)(ii) requires Pennsylvania's SIP 
to ``ensure compliance with the applicable requirements of section 7426 
* * * of this title'' (i.e., section 126 of the CAA). Because these 
requirements must become part of the SIP for Pennsylvania, they will be 
subject to enforcement in the same manner as any other requirement of a 
SIP. This includes the ability of third parties to raise challenges 
under the citizen suit provisions of section 304 of the CAA. Thus, New 
Jersey and its citizens will have ample opportunity for enforcement 
under these provisions of the statute.

VI. Increments of Progress

    This section discusses issues concerning whether and how EPA should 
establish appropriate increments of progress toward the final remedy. 
The statute does not define ``increments of progress.'' The EPA has 
discretion to define appropriate increments of progress on a case-by-
case basis. The increments of progress required in a particular case 
may vary depending on the facts of the petition but should provide 
incremental progress towards eventual compliance with the requirements 
of section 110(a)(2)(D)(i). Section VI.A discusses interim emission 
limits, and section VI.B discusses reporting milestones during the 3-
year period for the final remedy.

A. Interim Emission Limits

    As noted previously, section 126 allows the EPA to allow continued 
operation of a source beyond a 3-month time period if the source 
complies with ``emissions limitations and compliance schedules 
(including increments of progress). In this section we discuss issues 
related to whether the increments of progress should include interim 
emissions limits and the final rule requirements for progress 
milestones and reports.
1. What the EPA Proposed
    The EPA proposed interim emission limits for Portland units 1 and 
2. Specifically, the EPA proposed to require Portland to meet an 
SO2 emissions limit of 2,910 lb/hr for unit 1 and 4,450 lb/
hr for unit 2 within 1 year. These unit-specific emission limits 
represented 50 percent of the allowable emissions rate for each unit 
that was used for the EPA air quality modeling. The EPA proposed these 
interim reduction requirements because section 126 calls for 
``increments of progress,'' and because we believed that there were 
readily achievable interim steps that could be accomplished in this 
instance. In the proposal, the EPA discussed its evaluation of 
available SO2 emission reduction options for meeting the 
interim emissions limits such as reagent injection, switching to lower 
sulfur coal and load shifting. The EPA requested comment on the 
proposed interim reduction requirements for units 1 and 2, on the 
achievability of the limits in the 1-year time period proposed, and on 
the impact of the reductions on the reliability of the grid.
2. Public Comments and the EPA's Responses
a. Appropriateness of Including Interim Emissions Limits
    Comment: One commenter, GenOn, asserted that the EPA should not 
establish interim limits because those interim requirements may be 
inconsistent with the requirements of the Transport Rule or MATS 
requirements. Moreover, the same commenter believed that because the 
EPA has discretion not to impose interim emissions limits under section 
126(c), and because of this need for long-term harmonization with the 
Transport Rule, MATS and other requirements, the EPA is not justified 
in imposing the interim emissions limitations.
    Response: The EPA disagrees with comments that the EPA should 
exercise discretion provided by section 126 and remove the interim 
emissions limits from the final rule. As noted later in this section in 
our discussion of other GenOn comments, we believe that there

[[Page 69070]]

are readily available measures for Portland to make significant 
progress in the short term that in no way impede or conflict with 
achievement of the 3-year limits. Additionally, based on our assessment 
of the steps necessary to achieve these limits, implementation of these 
interim measures would complement, rather than conflict with, the 
measures needed for meeting this rule as well as the Transport Rule and 
MATS.
b. Technical Feasibility of Coal Switching
    Comment: In its comments, GenOn recommended that, should the EPA 
retain the interim emissions limitations, the EPA should defer them 
until GenOn can undertake necessary coal test burns to determine what 
limits are reliably achievable. GenOn comments further stated that it 
may be able to meet interim emissions limits if a reasonable time table 
and level is set based upon coal test burn results, but that a full 
evaluation of the practicality of interim limits was not possible by 
the June 13, 2011, deadline for public comments. GenOn indicated its 
intent to conduct initial coal testing by September 15, 2011. Finally, 
to provide GenOn with greater flexibility, GenOn requested that the EPA 
revise the form of any interim limits for Portland units 1 and 2; that 
is, the EPA should establish the limits as combined emissions limits 
for the total emissions from units 1 and 2 rather than establishing 
limits that would apply to each unit.
    Subsequent to the close of the comment period, GenOn submitted a 
report of the September 15, 2011, test burn referred to in its 
comments. For the final rule, the EPA took this test burn report into 
consideration. In the test burn, Portland blended its existing Northern 
Appalachia coal supply with varying amounts of low sulfur Central 
Appalachia coal from West Virginia. For each unit, the test burn 
assessed the impacts of varying blending cases on the unit's generator 
output, the reduction in SO2 emissions, and the effect on 
the performance of the electrostatic precipitators. The test burn 
report also noted facility changes in coal handling, feeder, and hopper 
systems that would be needed to allow for routine use and blending with 
lower sulfur coal in the future.
    In its comments, and in the later test burn report, GenOn commented 
that, based on initial evaluations of the coals economically available 
to be used to meet the proposed interim emission limits, the use of 
lower sulfur coal is projected to cause significant production derates 
at Portland units 1 and 2. That is, GenOn asserted that the total 
megawatts (MW) of electricity output from the plant would decrease if 
GenOn were to use a lower sulfur coal blend sufficient to meet the 
interim limits.
    Response: The EPA considered the test burn report along with other 
information relevant to the establishment of an interim limit. We 
continue to strongly believe that significant reductions in 
SO2 emissions can be achieved within 1 year. We do not 
disagree that, aside from a reduction in electrical output, the use of 
lower sulfur coal may indeed be the only viable option to meet interim 
limits at Portland. The EPA, however, remains convinced that lower 
sulfur Appalachian coals are readily available for use at Portland. 
This opinion is supported by recent Central Appalachian thermal coal 
quality and production data from Wood Mackenzie, published in April 
2011. According to Wood Mackenzie data, Central Appalachian production 
of thermal coal in 2010:
     Had a mean SO2 content of about 1.5 lb/mmBtu, 
which could allow a significant SO2 emission reduction from 
current coal usage, with ample margin to accommodate typical coal 
quality variations;
     Had a mean higher heating value of nearly 12,600 Btu/lb, 
which is likely well within 10 percent of the heating value currently 
used at Portland; and
     Amounted to about 130 million tons, including amounts that 
are about 50 times any possible maximum annual demand for low sulfur 
coal from Portland.
    The EPA is aware that changes in the characteristics of the coal 
(moisture content, ash content, grindability, etc.) used at Portland 
could change the performance of the Portland units. Although GenOn 
indicates that equipment modifications would be necessary to maintain 
the use of 100 percent CAAP coal for a sustained period of time, the 
EPA notes that during the test burn with 100 percent CAAP coal, the 
generator output for unit 1 is relatively close to rated capacity (162 
versus 171 MW, approximately 5 percent). Also the EPA notes that it is 
not unusual for installation of air pollution controls to result in a 
modest de-rate, and the EPA does not believe that maintenance of 100 
percent of current output should be seen as a constraint on the 
appropriateness of the interim limits. In addition, the test burn 
report, which evaluated one particular coal supply, is silent on the 
availability of a potentially more costly Central Appalachia coal that 
would allow each Portland unit to maintain closer to full load, and 
what boiler upgrades are necessary to improve generator output. The EPA 
is also aware of proven measures that the EPA believes can be applied 
relatively quickly to enhance PM control at Portland if needed due to 
coal switching, so as to meet a new, lower interim SO2 
emission limit while continuing to meet all other existing emissions 
limits. Two such measures include various upgrades to Portland's 
electrostatic precipitators (ESP) and/or use of flue gas conditioning, 
both of which have been routinely used by coal plant operators to 
improve or maintain ESP performance when switching to a lower sulfur 
coal that might impact performance.
    The EPA has reviewed the information from GenOn on the possible 
equipment changes, and has also reviewed our previous determinations of 
the time needed to accomplish those changes. The EPA's engineering 
judgment is that these changes can be accomplished within 1 year.
c. Interim Limits Suggested by the GenOn Test Burn Report
    Comment: Based on the results of the test burn report, GenOn 
concluded that (1) Sustained unit operations using a blend of Northern 
and Central Appalachia coals sufficient to achieve a 25 percent 
reduction in allowable SO2 emissions is achievable with a 
modest investment and an implementation schedule of 6 months, and (2) 
sustained unit operations using a blend of Northern and Central 
Appalachia coals to achieve a 35 percent reduction in allowable 
SO2 emissions should be achievable with additional 
investments and an implementation schedule of 8 to 12 months after 
GenOn has established an operational record and completed equipment 
performance evaluations at the 25 percent reduction blend level, and 
any necessary permits are acquired.
    Response: The EPA evaluated the suggested interim reductions in the 
GenOn test burn report. The EPA concluded that based upon this 
evaluation, these targets are significant underestimates of the readily 
available interim emissions reductions, represent very minimal 
reductions from current operations, and are inconsistent with the 
results of the test burn.
    Figure VI.C-1 shows the hourly SO2 emissions for all of 
2010 at Portland, shown as the sum of emissions from units 1 and 2. For 
the EPA (and GenOn's) air quality analysis, the assumed allowable 
emissions rates for units 1 and 2 were 5,820 lb/hr and 8,900 lb/hr, 
respectively, resulting in a total allowable rate of 14,720 lb/hour. A 
25

[[Page 69071]]

percent reduction from this amount, that is a 25 percent reduction from 
current allowable, thus becomes 11,040 lb/hr. As shown in Figure VI.C-
1, during 2010, Portland's hourly emissions exceeded 75 percent of 
allowable emissions only rarely. Accordingly, a 25 percent reduction in 
allowable emissions effectively represents status quo operations. A 35 
percent reduction in allowable emissions, or 9,568 lb/hr, would require 
at most a roughly 15 percent reduction in current emissions. EPA 
continues to believe that the facility can make much more significant 
reductions in line with the final interim limits within a year.
[GRAPHIC] [TIFF OMITTED] TR07NO11.021

d. Load Shifting
    Comment: GenOn commented on the EPA's assessment that the proposed 
interim limits could be met via ``load shifting.'' GenOn disagreed with 
the EPA's assessment that load shifting is a viable option to meet an 
interim limit. In its comments, GenOn interpreted the term ``load 
shifting'' as referring to the ability of a utility to continue to 
serve its customer load obligations by reducing utilization or ``load'' 
from a selected generator and increasing the output at other facilities 
owned by the same utility: The load is ``shifted'' to other generators 
that the company operates. Because GenOn's Portland plant is a merchant 
plant that operates in a competitive, centrally cleared and dispatched, 
Independent System Operator (ISO) market, GenOn noted that replacement 
energy likely would come from one of GenOn's competitors, and it is 
possible that Portland's production would be ``shifted'' to a less 
efficient unit that might have higher emissions than Portland units 1 
and 2. Additionally, as a ``capacity resource owner,'' GenOn is 
required under the Pennsylvania-New Jersey-Maryland Interconnection 
(PJM) tariff to bid the Portland units into the PJM energy market every 
day and make the units available to generate unless specific 
circumstances, such as a unit outage, arise that precludes operation of 
the plant.
    Response: The EPA agrees that the proposed rule could have used a 
clearer term than ``load shifting'' in describing the possible ways the 
interim emissions limits could be met. The EPA appreciates the 
distinction that GenOn makes in regard to load shifting within a 
utility's own assets versus load shifting in a competitive market. The 
EPA did not mean to imply in its brief mention of load shifting that we 
reached a conclusion that GenOn would merely shift any load reduction 
at Portland to another GenOn facility. Rather, our use of the imprecise 
term ``load shifting'' was referring to the ability of Portland to 
reduce its operation as a way to meet the interim lb/hr limits, or as a 
partial solution to meet the limits in combination with other 
approaches. The EPA recognizes the open market aspects of the PJM 
energy market including the probability that the load can shift to 
other operators. These market realities are characterized in detail in 
the models we use to forecast the effect of EGU regulations on the 
utility industry. In response to Portland's observation that

[[Page 69072]]

the facility that replaces Portland's output could be higher-emitting, 
the EPA observes that while its output would likely be more expensive 
than Portland's energy, there is a good possibility that the energy 
would be replaced with a scrubber or a gas-fired unit, either of which 
could have much lower emission rates than Portland, given the 
relatively high emission rate from Portland. As an older relatively 
uncontrolled plant, much of the generation capacity would be expected 
to emit less per unit of generation than the Portland facility.
e. One-Year Time Period
    Comment: One commenter, NJDEP, believed that the 1-year period 
allowed for too much time for the Portland facility to meet interim 
emissions limits, and that the interim limits were insufficiently 
stringent. NJDEP in their comments urged the EPA to ensure that we 
require interim reductions no less than 80 percent within 90 days.
    Response: The EPA disagrees with this comment. An 80 percent 
reduction would represent nearly the 81 percent reduction required by 
the 3-year limits in the final rule. As discussed in section VI.A 
above, we believe that the 3-year period is an ``expeditious'' schedule 
for emissions reductions of this magnitude, and that this level of 
reduction would not be achievable in a 90-day time period.
    Comment: Another commenter, PADEP, noted that if the proposed 50 
percent reduction in the maximum allowable SO2 emissions can 
only be achieved by the installation of sorbent injection technology, 
the 1-year deadline for complying with the interim limit does not 
provide sufficient time for permitting, purchasing, and installing the 
technology. Therefore, in lieu of setting specific interim emission 
limits and deadlines, PADEP recommended that the EPA work with NJDEP, 
GenOn, and PADEP, as the permitting agency, to establish emission 
interim emission limits and compliance schedules containing increments 
of progress consistent with CAA section 126(c).
    Response: The EPA believes that this approach would not be 
consistent with the statute. Under section 126, the Administrator is to 
set the emission limits and compliance schedules, and must accomplish 
these through a notice and comment rulemaking. While we have considered 
the comments of all the parties noted by the commenter, it would not be 
appropriate for the EPA to defer the compliance schedules to a future 
negotiation with the source owner and states.
    On the other hand, as discussed previously in section V.E, the EPA 
does agree with the commenter, and with others who made similar 
observations, that reagent injection may not be achievable within 1 
year because Portland may need to upgrade its particulate matter 
collection equipment. Accordingly, we no longer believe that reagent 
injection alone serves as a technical basis for the interim emissions 
reduction requirements in the final rule. Nevertheless, after analyzing 
the comments regarding the feasibility of switching to cleaner coal and 
the necessary time frame for doing so, we do believe that this is an 
appropriate basis for the interim limit. Thus, the EPA has determined 
that it is feasible for Portland to achieve interim reductions within 1 
year that would achieve significant progress toward the final remedy 
limits, would not interfere with Portland's progress toward meeting 
those final limits, and would result in important public health 
benefits in the interim.
f. Effect of Interim Limits on Reliability
    Comment: In response to the EPA's request for comments on the 
effects of the interim limits on electric reliability, one commenter 
noted that Portland is uniquely situated to supply power to the PJM 
power interconnection from a location close to the source of demand, 
that power transmissions coming from the Midwest are hampered by long 
distance transmission losses, and that transmission lines are already 
approaching overload. Another commenter, NJDEP, indicated that the 400 
MW generated by the plant is relatively small compared to PJM's current 
total capacity of 163,500 MW. NJDEP also concluded that it is unlikely 
that these units would be needed to prevent brownouts or blackouts, but 
that in the unlikely event that these units are necessary, the EPA 
could include a condition that the units may only be run when called on 
by PJM to provide power during a Maximum Emergency Generation Event.
    Response: The EPA agrees that given large reserve margins, we do 
not expect that the interim limit will cause adverse effects on 
electricity reliability. The EPA notes that the test burn reports cited 
above show that at worst, in meeting the interim limits the facility 
would be projected to continue operating under a small derate, and 
given the significant reserve margin noted by the commenters, continued 
operation of Portland at an occasionally lower rate would not be 
expected to have an adverse effect on the PJM system's ability to 
deliver needed power. Consequently, the EPA does not believe it is 
necessary to make any provision for use of Portland to address 
potential emergency events.
g. Clear Rationale for Limits
    Comment: One commenter, PADEP, noted its view that while section 
126 expressly provides for increments of progress, there is no 
provision in the CAA to suggest that a 50-percent reduction must be 
made within 1 year of a finding. Without the EPA fully explaining the 
rationale for these proposed interim emission reductions and timelines, 
this commenter believed the EPA's interim requirements could be viewed 
as arbitrary and capricious.
    Response: EPA has discretion under section 126 to establish 
reasonable interim emissions controls. For reasons discussed above, the 
EPA has a clear rationale for the interim emissions limits in the final 
rule. These limits are based upon the ready availability of coal with a 
sulfur content of 1.5 lb/mmBtu. We have reviewed the data on existing 
coal supplies, carefully reviewed information on available 
technologies, and established the interim limits based upon that 
review.
h. Combined Emission Limits
    Comment: GenOn requested in its comments that any interim emissions 
limits for Portland units 1 and 2 should be expressed as a combined 
limit for the two units, rather than on a unit-by-unit basis.
    Response: The EPA agrees with GenOn that for the interim limits, a 
substantial ``increment of progress'' towards meeting the ultimate (in 
this case, 3-year) limit is achievable regardless of whether the 
emissions limit is expressed as a combined limit or on a unit-by-unit 
basis. Accordingly, for the final rule, we are adopting an interim 
limit that will be a single combined limit, rather than separate 
limits, for units 1 and 2. As with the 3-year limit, the EPA will 
evaluate compliance based on available test data including part 75 CEMS 
data. The EPA believes that the combined limit will provide GenOn with 
greater flexibility to implement a variety of combinations of options 
to satisfy the interim limit, which should in turn serve to reinforce 
the EPA's view that there are readily available measures for Portland 
to employ in meeting the interim emissions reduction requirement.
    The EPA notes that for the interim emissions reduction, unlike the 
3-year limit, there is no explicit air quality goal defined by the Act. 
For the 3-year limit, it is essential that the limit ensure that 
Portland fully eliminates its significant

[[Page 69073]]

contribution to nonattainment and its interference with maintenance of 
the 1-hour SO2 NAAQS. For the interim reductions, however, 
the goal is to establish ``increments of progress'' towards meeting 
emissions limits that fully comply with section 126. Accordingly, for 
the 3-year limit, the EPA concluded it was essential for the final rule 
to include lb/mmBtu limits to ensure that the NAAQS were protected at 
all loads. However the EPA determined that it was not necessary to 
include similar lb/mmBtu limits for the interim limits. We also 
determined that establishing lb/mmBtu limits in the interim might 
unnecessarily restrict Portland's flexibility in the interim, since the 
1-year compliance deadline already constrains the available options to 
meet such a limit.
3. Final Rule Interim Emission Limits
    For the final rule, the EPA includes a combined interim limit of 
6,253 lb/hour for the total SO2 emissions from units 1 and 
2.
    The basis for the final limit differs from the proposed rule. For 
the proposal, the EPA calculated the unit-by-unit proposed limits as 50 
percent of the allowable emissions rate used for the EPA air quality 
modeling. We believe that for the final rule it is preferable to base 
these interim limits on coal characteristics of readily available coal 
supplies. For the final rule, the combined interim limit is based on 
the EPA's assessment that coal with sulfur content of 1.5 lb/mmBtu is 
readily available and its use at Portland is achievable within 1 year. 
Using this 1.5 lb/mmBtu value as the basis for the calculation of the 
combined interim limit, we calculated \22\ the limit as follows:
---------------------------------------------------------------------------

    \22\ Heat input capacities of 1657.2 and 2511.6 mmBtu/hr are 
those listed in the title V permit for Portland units 1 and 2.

For Unit 1: 1657.2 mmBtu/hr x 1.5 lb/mmBtu = 2486 lb/hr
For Unit 2: 2511.6 mmBtu/hr x 1.5 lb/mmBtu = 3767 lb/hr
    Total combined emission rate = 6253 lb/hr

    We agree with the commenters who feel strongly that this interim 
limit is very important to include in the final rule, not only because 
it drives progress toward the final remedy, but also because of the air 
quality and public health benefits that will be realized in the 
interim. While the limit is not calculated based on specific air 
quality criteria, these readily available interim reductions will serve 
to markedly reduce the number of days with SO2 violations in 
New Jersey, and will serve to greatly reduce SO2 
concentrations on days with remaining violations. We do not know what 
specific approach Portland will use to comply with the interim limit, 
so we cannot quantify the decrease in SO2 concentrations at 
specific locations, but we do note that the interim limits will result 
in significant SO2 emissions reductions within the first 
year and make important progress toward the elimination of 
SO2 violations within 3 years. These limits represent a 46-
percent decrease from peak 2010 actual emissions. Moreover, the most 
significant reductions will occur during the hours when the emissions 
are the highest. During 2010, more than 40 percent of the hours that 
Portland operated resulted in emissions that exceeded 6253 lb/hr. The 
interim limit will ensure that such high emissions during those times 
are eliminated.

B. Increments of Progress: Reporting Milestones

1. What the EPA Proposed
    In addition to the proposed 3-year and 1-year emissions limits, the 
EPA proposed a schedule of milestones that must be achieved to provide 
assurance that the source is on track to achieve full compliance as 
expeditiously as practicable and no later than the 3-year deadline.
    Those proposed milestones were:
    3-month notification: Within 3 months of the EPA's finding, the EPA 
proposed that GenOn notify the EPA whether it will cease to operate 
within that period or whether it will continue to operate subject to 
the emission limitations and compliance schedules in the final 
rulemaking. If Portland plans to continue to operate subject to these 
limits, the EPA proposed to require Portland to indicate how it intends 
to achieve full compliance with the emission limits. Specifically, we 
proposed that Portland must indicate whether it intends to cease or 
reduce operation at any emission unit subject to emission limits as its 
method of compliance with such limits. If this 3-month notice indicated 
that Portland intends to continue operation, the proposed rule required 
the remaining reporting requirements also be satisfied.
    Modeling protocol and analysis: No later than 3 months from the 
date of the section 126 finding, we proposed that GenOn submit to the 
EPA a modeling protocol (including all units at Portland in the 
protocol), consistent with our Guideline on Air Quality Models. If the 
EPA identified deficiencies in the modeling protocol submitted by the 
source, we proposed to require Portland to submit a revision to correct 
any deficiencies within 15 business days. We proposed to require that 
Portland submit a modeling analysis in accordance with the approved 
protocol within 6 months.
    Status reports: We proposed to require GenOn to submit, beginning 6 
months after the section 126 finding and continuing every 6 months 
until the final compliance date, a progress report on the 
implementation of the remedy, including status of design, technology 
selection, development of technical specifications, awarding of 
contracts, construction, shakedown, and compliance demonstration.
    Interim project report: We proposed to require GenOn to submit 
within 1 year an interim project report demonstrating compliance with 
the 1-year limits.
    Final project report: We proposed to require GenOn to submit, 
within 3 years, a final project report which demonstrates compliance 
with the emission limits in the final rulemaking. We proposed that this 
final report include the date when full operation of controls was 
achieved at Portland after shakedown; as well as a minimum of 1 month 
of CEMS data demonstrating compliance with the emission limits in the 
final rulemaking.
2. Public Comments and the EPA's Responses
    One commenter, GenOn, objected to both the 90-day compliance plan 
and the periodic status reports. The commenter believed that requiring 
a detailed plan 90 days after the final rule is unnecessarily 
restrictive, particularly given that GenOn will not have fully 
evaluated its compliance options under MATS. Similarly, GenOn believed 
that detailed status reports are not justified and will limit GenOn's 
flexibility to revise its compliance strategy in response to other 
state and federal regulations. Because the regulatory environment is 
fluid with further changes expected, GenOn expressed concerns that the 
compliance plan and status reports should not restrict GenOn's ability 
to revise its strategy for compliance with section 126 as circumstances 
change.
    One commenter believed that the schedule for a required modeling 
protocol within 3 months was overly ambitious and suggested the owner 
and operator of Portland should have at least 6 months to submit a 
modeling protocol for Portland's SO2 emissions.
3. Final Rule Reporting Milestones
    For the final rule, the EPA has amended the proposed requirement 
for GenOn to develop a compliance plan with an identified remedy with 
90 days.

[[Page 69074]]

The EPA agrees with GenOn that it is very possible that complete 
information to inform this remedy may not be available within 90 days 
of the rule's effective date. The EPA does, however, believe that in 
order to implement controls it is reasonable to assume that information 
necessary for a decision will be available within 12 months of the 
effective date, and accordingly we have retained the requirement but 
have postponed the deadline until 12 months after the effective date of 
the final rule. The EPA acknowledges the commenters' point that there 
are factors over time that could lead to a revised decision after the 
12 month milestone. Even if such factors lead to a different eventual 
remedy, the EPA believes that it is nonetheless reasonable to require a 
status report on GenOn's intent at the 12 month point in order to 
ensure that planned actions for compliance with the requirements of 
section 126 are on track.
    The EPA has also retained the requirements for 6 month status 
reports. We disagree with comments that these reports are not 
justified. The status reports required by this rule are warranted not 
only because section 126 requires ``increments of progress,'' but in 
addition the EPA believes these are necessary for the EPA and the 
states to monitor Portland's efforts to achieve compliance with the 
emission limits established in this rule. The status reports are not 
exhaustive, but will provide important information to the agency and to 
the public to monitor Portland's progress towards the ultimate goal of 
reducing its SO2 emissions and reducing its impact on New 
Jersey's compliance with the 1-hour SO2 NAAQS.
    We have also retained the requirement for the interim and final 
progress reports. For the final rule, we have extended the deadline for 
the final project report by two months to provide time for evaluation 
of CEMS data before submitting the report.
    In the final rule, we have retained the requirement to submit a 
modeling protocol and modeling, but, after consideration of the timing 
concerns raised by commenters, we have amended the deadlines. For the 
final rule, the modeling protocol is required within 6 months of this 
rulemaking and the final modeling within 12 months. The revisions to 
the interim compliance schedule outlined in this section are all 
logical outgrowths of the compliance schedule originally proposed as 
they were made in response to consideration of the comments received in 
response to that proposal.

VII. Alternate Compliance Schedule and Consideration of Petition for 
Rulemaking for Alternative Emission Limits

    In this section, we discuss two additional overarching issues on 
which we sought comment in the proposal. First we discuss our decision 
regarding the proposed consideration of an alternative schedule based 
upon Portland's decision to meet its compliance obligations by electing 
to shut down unit 1 or unit 2, or both. We then discuss the potential 
for additional rulemaking to accommodate alternative remedies from 
those established in this rule.

A. Alternate Compliance Schedule if the Source Owner Opts To Cease 
Operations

1. What the EPA Proposed
    In the preamble to the proposed rule, the EPA discussed why 
different remedies for meeting the requirements of section 126 may 
suggest different compliance schedules, 76 FR 19678. In particular, the 
EPA noted that if GenOn decided to cease operation of the Portland 
facility, it is possible that implementing such a remedy ``as 
expeditiously as practicable'' may have different considerations than 
if it decided to undertake a schedule of constructing and implementing 
control technologies. Consistent with this perceived possibility, the 
EPA requested comment in the proposal on how to interpret the phrase 
``as expeditiously as practicable'' when the source owner and operator 
has elected to cease operation as its method of compliance with the 
emissions limit for a given unit and cessation cannot occur within 3 
months of the EPA's finding. The EPA noted that if appropriate based 
upon comments, the EPA would consider including in the final rule an 
alternate compliance schedule for this possibility, and the EPA 
requested comment on relevant factors that should be considered were we 
to include such an alternate schedule.
2. Public Comments and the EPA's Responses
    Comment: One commenter stated that if the facility elected to 
close, it must be required to cease operation immediately, as there is 
no basis to allow the plant to continue to significantly contribute to 
nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey. Another commenter suggested that if 
Portland plans to cease operations of the coal burning units, shutdown 
should occur within 3 months of the EPA's final rule.
    Response: The EPA notes that section 126(c) of the CAA allows the 
EPA to permit continued operation beyond 90 days if the source complies 
with emissions limitations and compliance schedules established by the 
Administrator. This language does not, however, mandate that any 
decision to cease operation must occur in any particular time period 
when the source is otherwise complying with the required emission 
limits compliance schedules. The EPA disagrees with commenters 
suggestion that any decision to shutdown must occur immediately or 
within 90 days. For the final rule, the EPA concludes that the final 
and interim emission limits and reporting milestones are sufficient for 
all selected remedies, including a remedy under which GenOn would 
choose to ultimately cease operation at one or more units. The EPA has 
made this conclusion because compliance with the interim and final 
emission limits, regardless of how the plant chooses to comply, results 
in the elimination of Portland's significant contribution to the 
affected areas in New Jersey and demonstrates appropriate interim 
progress towards such elimination.
3. The Final Rule
    The EPA has retained the approach in the proposed rule, and we have 
not included an alternative compliance schedule in the case that the 
selected remedy is to cease operation of unit 1 and/or unit 2. The EPA 
did not receive any information in comments that leads the EPA to 
conclude that a different schedule is necessary.

B. Consideration of Petition for Rulemaking for Alternative Emission 
Limits

    The EPA received comment from GenOn arguing that the unit-specific 
SO2 limits for unit 1 and for unit 2 did not provide GenOn 
with sufficient flexibility. Accordingly, GenOn recommended that the 
EPA change the form of the final emissions limits to a combined 
emissions limit for the total emissions from units 1 and 2. In this 
way, they asserted GenOn would be able to evaluate a broader suite of 
remedies which could possibly include remedies with equivalent air 
quality impacts at substantially reduced cost.
    The EPA understands the source's request for operational 
flexibility, and we considered the option suggested by GenOn. However, 
based on the modeling analysis conducted by the EPA, we are not able to 
set a combined

[[Page 69075]]

limit for the final remedy. The final rule contains individual final 
limits that are specific to units 1 and 2. There are some combinations 
of emissions from units 1 and 2 which will be protective of the NAAQS 
and some that will not. Air quality modeling results indicated that 
there are many possible scenarios under which a combined limit, of 
similar stringency to the limits adopted, would lead to exceedances of 
the 1-hour SO2 NAAQS. In particular, given the multiple 
possibilities of available controls for the two units, there would be a 
large number of possible stack configurations with different dispersion 
characteristics. While the EPA perhaps could have developed a combined 
limit with sufficient stringency to ensure that all significant 
contribution and interference with maintenance would be eliminated 
under every possible combination of control options and stack 
configurations, the EPA does not believe that this approach would 
provide the flexibility that GenOn is seeking because the combined 
limit would likely need to be much more stringent than the limits in 
the final rule.
    Nevertheless, we acknowledge the greater operating flexibility that 
an alternative set of emission limits might offer, and we note that in 
some cases an appropriately constrained combined limit may be possible 
to construct in a way that is protective of the NAAQS (e.g., more 
stringent than the sum of the individual limits). Should GenOn wish to 
have a higher limit at one of the units, in exchange for a lower limit 
at the other, or seek a combined limit that is protective of the NAAQS 
in all cases, the source may petition the EPA for additional rulemaking 
to adopt alternative emissions limits if such petition demonstrates 
that the proposed alternative would eliminate all emissions at Portland 
that significantly contribute to nonattainment or interfere with 
maintenance of the 1-hour SO2 NAAQS in New Jersey by the 3-
year deadline established in this rule. As part of the interim 
reporting requirements, the rule requires GenOn to submit a modeling 
analysis, pursuant to a modeling protocol that it is consistent with 
the data and methods the EPA used to develop this rule, which shows 
that the final compliance remedy is protective of the NAAQS. If GenOn 
chooses to submit such a petition, the EPA expects GenOn to provide a 
demonstration, in the course of conducting the modeling analysis 
required by the rule, that shows that a specific alternative set of 
emissions limits for unit 1 and unit 2 would also be protective of the 
1-hour SO2 NAAQS in New Jersey. In order for the EPA to 
consider such a rulemaking petition, GenOn would need to submit, no 
later than the 1-year deadline for submitting modeling results under 
the rule, any proposed alternative limits along with air quality 
modeling, consistent with the approved modeling protocol, demonstrating 
that the proposed alternative limits would, at all operating loads, 
eliminate Portland's significant contribution to nonattainment and 
interference with maintenance in New Jersey. If the EPA determines it 
would be appropriate to propose approval of the alternative emission 
limits, the EPA would conduct a notice and comment rulemaking on the 
proposed alternative.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action will grant the NJDEP petition and is making a CAA 
section 126 finding. This type of action is exempt from review under 
Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 
3821, January 21, 2011).

B. Paperwork Reduction Act

    This action does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. 
Burden is defined at 5 CFR 1320.3(b). Under the Paperwork Reduction 
Act, a ``collection of information'' is defined as a requirement for 
``answers to * * * identical reporting or recordkeeping requirements 
imposed on ten or more persons * * *.'' 44 U.S.C. 3502(3)(A). Because 
the rule applies to a single facility, Portland, the Paperwork 
Reduction Act does not apply. See 5 CFR 1320(c).

C. Regulatory Flexibility Act (RFA)

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to prepare a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements under the Administrative 
Procedure Act or any other statute unless the agency certifies that the 
rule will not have a significant economic impact on a substantial 
number of small entities. Small entities include small businesses, 
small organizations, and small governmental jurisdictions.
    For purposes of assessing the impacts of this rule on small 
entities, small entity is defined as: (1) A small business as defined 
by the Small Business Administration's (SBA) regulations at 13 CFR 
121.201; (2) a small governmental jurisdiction that is a government of 
a city, county, town, school district or special district with a 
population of less than 50,000; and (3) a small organization that is 
any not-for-profit enterprise which is independently owned and operated 
and is not dominant in its field.
    After considering the economic impacts of this final rule on small 
entities, I certify that this rule will not have a significant economic 
impact on a substantial number of small entities. This final rule will 
not impose any requirements on small entities because small entities 
are not subject to the requirements of this rule.

D. Unfunded Mandates Reform Act of 1995 (UMRA)

    This rule does not contain a federal mandate that may result in 
expenditures of $100 million or more for state, local, and tribal 
governments, in the aggregate, or the private sector in any 1 year. The 
cost necessary to comply with the limits in this notice are not 
expected to exceed $100 million. Thus, this rule is not subject to the 
requirements of sections 202 or 205 of UMRA.
    This rule is also not subject to the requirements of section 203 of 
UMRA because it contains no regulatory requirements that might 
significantly or uniquely affect small governments. The requirements 
for compliance in this rule will be borne by a single, privately owned 
source.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132. The rule primarily affects the 
private industry, and does not impose significant economic cost on 
state or local governments or preempt state or local law. Thus, 
Executive Order 13132 does not apply to this action.
    In the spirit of Executive Order 13132, and consistent with the 
EPA's policy to promote communications between the EPA and state and 
local governments, the EPA specifically solicited comment on the 
proposed action from state and local officials.

[[Page 69076]]

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications, as specified in 
Executive Order 13175 (65 FR 67249, November 9, 2000). It does not have 
a substantial direct effect on one or more Indian Tribes. Furthermore, 
this action does not affect the relationship between Indian Tribes and 
the federal government, or distribution of power and responsibilities 
between the federal government and Indian Tribes. Thus, Executive Order 
13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    The EPA interprets Executive Order 13045 (62 FR 19885, April 23, 
1997) as applying only to those regulatory actions that concern health 
or safety risks, such that the analysis required under section 5-501 of 
the Executive Order has the potential to influence the regulation. This 
action is not subject to Executive Order 13045 because it does not 
involve decisions on environmental health or safety risks that may 
disproportionately affect children. The EPA believes that the emissions 
reductions in this rule will further improve air quality and will 
further improve children's health.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution, or Use

    This action is not subject to Executive Order 13211 (66 FR 28355 
(May 22, 2001)), because it is an exempted action under Executive Order 
12866.

I. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629, February 16, 1994) establishes 
Federal executive policy on environmental justice. Its main provision 
directs federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the U.S.
    The EPA has determined that this final rule will not have 
disproportionately high and adverse human health or environmental 
effects on minority or low-income populations because it increases the 
level of environmental protection for all affected populations without 
having any disproportionately high and adverse human health or 
environmental effects on any population, including any minority or low-
income population.
    The agency has also reviewed this rule to determine if there is 
existing disproportionately high and adverse human health or 
environmental effects on minority or low-income populations that could 
be mitigated by this rulemaking. An analysis of demographic data 
illustrates that the population residing near the source is represented 
by fewer minority and low-income residents than either the surrounding 
counties, the average demographic composition of the states of New 
Jersey and Pennsylvania, and national averages. In addition, this rule 
increases the level of environmental and public health protection for 
all affected populations since, when fully implemented, it will result 
in attainment of the health-based 1-hour SO2 NAAQS. The 
results of the demographic analysis are presented in the supporting 
document titled, ``Environmental Justice Assessment for Section 126 
Petition from New Jersey Regarding SO2 Emissions from the 
Portland Generating Station'' (September 2011), a copy of which is 
available in the docket EPA-HQ-OAR-2011-0081.

J. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer Advancement Act 
of 1995 (NTTAA), Public Law No. 104-113, section 12(d) (15 U.S.C. 272 
note) directs the EPA to use voluntary consensus standards (VCS) in its 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impracticable. VCS are technical standards 
(e.g., materials specifications, test methods, sampling procedures, and 
business practices) that are developed or adopted by VCS bodies. The 
NTTAA directs the EPA to provide Congress, through OMB, explanations 
when the agency decides not to use available and applicable VCS.
    This action does not involve technical standards. Therefore, the 
EPA did not consider the use of any VCS.

K. Congressional Review Act

    The Congressional Review Act, 5 U.S.C 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. Section 804 exempts from section 801 the following types 
of rules (1) Rules of particular applicability; (2) rules relating to 
agency management or personnel; and (3) rules of agency organization, 
procedure, or practice that do not substantially affect the rights or 
obligations of non-agency parties. 5 U.S.C. 804(3). The EPA is not 
required to submit a rule report regarding today's action under section 
801 because this is a rule of particular applicability. Nonetheless, 
this action will be effective January 6, 2012.

L. Judicial Review

    Under section 307(b)(1) of the CAA, petitions for judicial review 
of this action must be filed in the United States Court of Appeals for 
the District of Columbia Circuit Court within 60 days from the date the 
final action is published in the Federal Register. Filing a petition 
for review by the Administrator of this final action does not affect 
the finality of this action for the purposes of judicial review nor 
does it extend the time within which a petition for judicial review 
must be final, and shall not postpone the effectiveness of such action.
    Thus, any petitions for review of this action related to the 
section 126 finding must be filed in the Court of Appeals for the 
District of Columbia Circuit within 60 days from the date final action 
is published in the Federal Register.

List of Subjects in 40 CFR Part 52

    Approval and promulgation of implementation plans, Environmental 
protection, Administrative practice and procedures, Air pollution 
control, Incorporation by reference, Intergovernmental relations, and 
Reporting and recordkeeping requirements, Sulfur dioxide.

    Dated: October 31, 2011.
Lisa P. Jackson,
Administrator.
    For the reasons set forth in the preamble part 52 of chapter I of 
title 40 of the Code of Federal regulations is amended as follows:

PART 52--[AMENDED]

0
1. The authority citation for part 52 continues to read as follows:

     Authority:  42 U.S.C. 7401 et seq.

Subpart NN--Pennsylvania

0
2. Section 52.2039 is added to read as follows:

[[Page 69077]]

Sec.  52.2039   Interstate transport.

    The EPA has made a finding pursuant to section 126 of the Clean Air 
Act (the Act) that emissions of sulfur dioxide (SO2) from 
the Portland Generating Station in Northampton County, Upper Mount 
Bethel Township, Pennsylvania (Portland) significantly contribute to 
nonattainment and interfere with maintenance of the 1-hour 
SO2 national ambient air quality standard (NAAQS) in Morris, 
Sussex, Warren, and Hunterdon Counties in New Jersey. The owners and 
operators of Portland shall comply with the requirements in paragraphs 
(a) through (d) of this section.
    (a) The owners and operators of Portland shall not, at any time 
later than one year after the effective date of the section 126 
finding, emit SO2 (as determined in accordance with part 75 
of this chapter) in excess of 6,253 pounds per hour (lb/hr) for unit 1 
(identified with source ID 031 in Title V Permit No. 48-0006) and unit 
2 (identified with source ID 032 in Title V Permit No. 48-0006) 
combined;
    (b) The owners and operators of Portland shall not, at any time 
later than three years after the effective date of the section 126 
finding, emit SO2 (as determined in accordance with part 75 
of this chapter) in excess of the following limits:
    (1) 1,105 lb/hr and 0.67 pounds per million British Thermal Unit 
(lb/mmBtu) for unit 1; and
    (2) 1,691 lb/hr and 0.67 lb/mmBtu for unit 2.
    (c) The owners and operators of Portland shall comply with the 
following requirements:
    (1) Perform air modeling to demonstrate that, starting no later 
than three years after the effective date of the section 126 finding, 
emissions from Portland will not significantly contribute to 
nonattainment or interfere with maintenance of the 1-hour 
SO2 NAAQS in New Jersey, in accordance with the following 
requirements:
    (i) No later than six months after the effective date of the 
section 126 finding, submit to the EPA a modeling protocol that is 
consistent with the EPA's Guideline on Air Quality Models, as codified 
at 40 CFR Part 51, Appendix W, and that includes all units at the 
Portland Generating Station in the modeling.
    (ii) Within 15 business days of receipt of a notice from the EPA of 
any deficiencies in the modeling protocol under paragraph (d)(1)(i) of 
this section, submit to the EPA a revised modeling protocol to correct 
any deficiencies identified in such notice.
    (iii) No later than one year after the effective date of the 
section 126 finding, submit to the EPA a modeling analysis, performed 
in accordance with the modeling protocol under paragraphs (c)(1)(i) and 
(c)(1)(ii) of this section, for the compliance methods identified in 
the notice required by paragraph (c)(2) of this section.
    (2) No later than one year after the effective date of the section 
126 finding, submit to the EPA the compliance method selected by the 
owners and operators of Portland to achieve the emissions limits in 
paragraph (b) of this section.
    (3) Starting six months after the effective date of the section 126 
finding and continuing every six months until three years after the 
effective date of the section 126 finding, submit to the EPA progress 
reports on the implementation of the methods to achieve compliance with 
emissions limits in paragraphs (a) and (b) of this section, including 
status of design, technology selection, development of technical 
specifications, awarding of contracts, construction, shakedown, and 
compliance demonstrations as applicable. These reports shall include:
    (i) An interim project report, no later than one year after the 
effective date of the section 126 finding, that demonstrates compliance 
with the emission limit in paragraph (a) of this section.
    (ii) A final project report, submitted no later than 60 days after 
three years after the effective date of the section 126 finding, that 
demonstrates compliance with the emission limits in paragraph (b) of 
this section and that includes at least one month of SO2 
emission data from Portland's continuous SO2 emission 
monitor, and that includes the date when full operation of controls was 
achieved at Portland after shakedown.
    (4) The requirements in paragraphs (c)(1) and (c)(3) of this 
section shall not apply if the notice required by paragraph (c)(2) of 
this section indicates that the owners and operators of Portland have 
decided to completely and permanently cease operation of unit 1 and 
unit 2 as the method of compliance with paragraphs (a) and (b) and with 
section 126 of the Act.
    (d) Compliance with the lb/mmBtu limitations in paragraph (b) of 
this section is determined on a 30 boiler operating day rolling average 
basis. Boiler operating day for the purposes of this paragraph means a 
24-hour period between midnight and the following midnight during which 
any fuel is combusted in the units identified in paragraph (a) of this 
section.

[FR Doc. 2011-28816 Filed 11-4-11; 8:45 am]
BILLING CODE 6560-50-P