Document ID: EPA-HQ-OAR-2011-0081-0001
Agency: epa
Document Type: Proposed Rule
Title: Response to Petition from New Jersey Regarding SO2 Emissions from the Portland Generating Station
Posted Date: 2011-04-07T04:00Z

[Federal Register Volume 76, Number 67 (Thursday, April 7, 2011)]
[Proposed Rules]
[Pages 19662-19681]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-8166]

[[Page 19661]]

Vol. 76

Thursday,

No. 67

April 7, 2011

Part III

Environmental Protection Agency

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40 CFR Part 52

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

  Federal Register / Vol. 76 , No. 67 / Thursday, April 7, 2011 / 
Proposed Rules  

[[Page 19662]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-HQ-OAR-2011-0081; FRL-9291-2]
RIN 2060-AQ69

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

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: In this action, EPA proposes to make a finding that the coal-
fired Portland Generating Station (Portland Plant) 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, EPA is proposing to find that 
emissions of sulfur dioxide (SO2) from the Portland Plant 
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 proposed in response to 
a petition submitted by the State of New Jersey Department of 
Environmental Protection (NJDEP) on September 17, 2010. In this action, 
EPA is also proposing emission limitations and compliance schedules to 
ensure that the Portland Plant will no longer significantly contribute 
to nonattainment, and no longer interfere with maintenance of the 1-
hour SO2 NAAQS, thereby permitting continued operation of 
the Portland Plant beyond the 3-month limit established by the CAA for 
sources subject to such a finding.

DATES: Comments. Comments must be received on or before May 27, 2011.
    Public Hearing: A public hearing will be held on April 27, 2011, in 
the Pequest Trout Hatchery and Natural Resources Education Center 
located in Oxford, Warren County, New Jersey 07863. Please refer to 
SUPPLEMENTARY INFORMATION for additional information on the comment 
period and the public hearing.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2011-0081 by one of the following methods:
     http://www.regulations.gov. Follow the online instructions 
for submitting comments. Attention Docket ID No. EPA-HQ-OAR-2011-0081.
     E-mail: a-and-r-docket@epa.gov. Attention Docket ID No. 
EPA-HQ-OAR-2011-0081.
     Fax: (202) 566-9744. Attention Docket ID No. EPA-HQ-OAR-
2011-0081.
     Mail: EPA Docket Center, EPA West (Air Docket), Attention 
Docket ID No. EPA-HQ-OAR-2011-0081, U.S. Environmental Protection 
Agency, Mailcode: 2822T, 1200 Pennsylvania Avenue, NW., Washington, DC 
20460. Please include a total of 2 copies. Hand Delivery: U.S. 
Environmental Protection Agency, EPA West (Air Docket), 1301 
Constitution Avenue, Northwest, Room 3334, Washington, DC 20004, 
Attention Docket ID No. EPA-HQ-OAR-2011-0081. Such deliveries are only 
accepted during the Docket's normal hours of operation, and special 
arrangements should be made for deliveries of boxed information.
    Instructions. Direct your comments to Docket ID No. EPA-HQ-OAR-
2011-0081. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
http://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit information that you 
consider to be CBI or otherwise protected through http://www.regulations.gov or e-mail. The http://www.regulations.gov Web site 
is an ``anonymous access'' system, which means EPA will not know your 
identity or contact information unless you provide it in the body of 
your comment. If you send an e-mail comment directly to EPA without 
going through http://www.regulations.gov, your e-mail address will be 
automatically captured and included as part of the comment that is 
placed in the public docket and made available on the Internet. If you 
submit an electronic comment, EPA recommends that you include your name 
and other contact information in the body of your comment and with any 
disk or CD-ROM you submit. If EPA cannot read your comment due to 
technical difficulties and cannot contact you for clarification, EPA 
may not be able to consider your comment. Electronic files should avoid 
the use of special characters, avoid any form of encryption, and be 
free of any defects or viruses. For additional information about EPA's 
public docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket. All documents in the docket are listed in the http://www.regulations. gov index. Although listed in the index, some 
information is not publicly available, e.g., 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. 
Publicly available docket materials are available either electronically 
in http://www.regulations 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), 
hawes.todd@epa.gov, or Ms. Gobeail McKinley (919-541-5246), 
mckinley.gobeail@epa.gov, Air Quality Policy Division, Office of Air 
Quality Planning and Standards (C539-04), Environmental Protection 
Agency, Research Triangle Park, NC 27711.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Where can I get a copy of this document and other related 
information?

    In addition to being available in the docket, an electronic copy of 
this proposal will also be available on the World Wide Web. Following 
signature by the EPA Administrator, a copy of this action will be 
posted on EPA's Web site http://www.epa.gov/ttn/oarpg/new.html.

B. What should I consider as I prepare my comments for EPA?

    1. Submitting CBI. Do not submit this information to EPA through 
http://www.regulations.gov or e-mail. Clearly mark the part or all of 
the information that you claim to be CBI. For CBI information in a disk 
or CD ROM that you mail to EPA, mark the outside of the disk or CD ROM 
as CBI and then identify electronically within the disk or CD ROM the 
specific information that is claimed as CBI. In addition to one 
complete version of the comment that includes information claimed as 
CBI, a copy of the comment that does not contain the information 
claimed as CBI must be submitted for inclusion in the public docket. 
Information so marked will not be disclosed except in accordance with 
procedures set forth in 40 CFR part 2. Send or deliver information 
identified as CBI only to the following address: Roberto Morales, OAQPS 
Document Control Officer (C404-02), U.S. EPA, Research Triangle

[[Page 19663]]

Park, NC 27711, Attention Docket ID No. EPA-HQ-OAR-2011-0081.
    2. Tips for preparing your comments. When submitting comments, 
remember to:
     Identify the rulemaking by docket number and other 
identifying information (subject heading, Federal Register date and 
page number).
     Follow directions--The agency may ask you to respond to 
specific questions or organize comments by referencing a Code of 
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow for it to be 
reproduced.
     Provide specific examples to illustrate your concerns, and 
suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.

C. How can I find information about the public hearing?

    The EPA will hold a public hearing on this proposal on April 27, 
2011. The hearing will be held at the following location: Pequest Trout 
Hatchery and Natural Resources Education Center located on 605 Pequest 
Road in Oxford, New Jersey 07863. The public hearing will begin at 12 
noon and continue until 8 p.m., or later if necessary depending on the 
number of speakers. The EPA will make every effort to accommodate all 
speakers that arrive and register before 8 p.m. A dinner break is 
scheduled from 4 p.m. until 5 p.m. during the hearing. Oral testimony 
will be limited to 5 minutes per commenter. The EPA encourages 
commenters to provide written versions of their oral testimonies either 
electronically or in paper copy. Verbatim transcripts and written 
statements will be included in the rulemaking docket. If you would like 
to present oral testimony at the hearing, please notify Ms. Pam S. 
Long, Air Quality Policy Division (C504-03), U.S. EPA, Research 
Triangle Park, NC 27711, telephone number (919) 541-0641, 
long.pam@epa.gov. Persons interested in presenting oral testimony 
should notify Ms. Long at least 2 days in advance of the public 
hearing. Commenters should notify Ms. Long if they will need specific 
equipment, or if there are other special needs related to providing 
comments at the public hearing. The EPA will provide equipment for 
commenters to show overhead slides or make computerized slide 
presentations if we receive special requests in advance. The EPA 
encourages commenters to provide EPA with a copy of their oral 
testimony electronically (via e-mail or CD) or in hard copy form. For 
updates and additional information on the public hearing, please check 
EPA's Web site for this rulemaking, http://www.epa.gov/ttn/oarpg/new.html. The public hearing will provide interested parties the 
opportunity to present data, views, or arguments concerning the 
proposed rule. The EPA may ask clarifying questions during the oral 
presentations, but will not respond to the presentations or comments at 
that time. Written statements and supporting information submitted 
during the comment period will be considered with the same weight as 
any oral comments and supporting information presented at a public 
hearing.

D. How is the preamble organized?

SUPPLEMENTARY INFORMATION: 

I. General Information
    A. Where can I get a copy of this document and other related 
information?
    B. What should I consider as I prepare my comments for EPA?
    C. How can I find information about a public hearing?
    D. How is the preamble organized?
II. EPA's Proposed Decision on NJDEP's September 17, 2010 Section 
126 Petition
III. Background
    A. Section 126 of the Clean Air Act
    B. Summary of Section 126 Petitions Submitted by NJDEP
    1. NJDEP's May 13, 2010 Petition
    2. NJDEP's September 17, 2010 Petition
    C. EPA Extensions for Acting on the Section 126 Petitions
    D. Background on the Portland Plant and Its Surrounding Area
    E. Sulfur Dioxide and Public Health
IV. EPA's Methodology for Making the Proposed Section 126 Finding 
for the Portland Plant
    A. EPA's Approach for Determining Whether To Make a Section 126 
Finding for the Portland Plant
    1. CAA Section 126(b)
    2. EPA's Approach To Evaluating NJDEP's Section 126 Petition
V. Summary and Assessment of the Modeling and Other Data Relevant to 
EPA's Finding
    A. Summary of the Modeling Submitted by NJDEP To Support the 
Petition
    B. EPA's Assessment of the Modeling Submitted by NJDEP
    1. NJDEP's Model Selection
    a. CALPUFF Alternative Model Justification
    2. Emissions and Source Characteristics
    3. Meteorological Data
    4. Receptor/Terrain Data
    5. AERMOD Results
    C. Summary of NJDEP's Trajectory Analysis and the Columbia Lake 
Monitor
VI. EPA's Decision on Whether To Make a Section 126 Finding or Deny 
the Petition
VII. EPA's Proposed Remedy
    A. Quantification of the Emission Reductions Necessary To 
Eliminate the Portland Plant's Significant Contribution
    1. Summary of EPA's Remedy Modeling for 1-Hour SO2 
NAAQS
    2. Model Selection
    3. Meteorological Data
    4. Receptor/Terrain Data
    5. Portland Plant Emissions and Source Characteristics
    6. Identification of Background Concentration To Use in the 
Remedy Analysis
    7. Summary of EPA's Modeling Results
    a. Calculation of Emissions Limits Based on Maximum Modeled 
Impacts From Units 1 and 2 Plus Background
VIII. Proposed Emission Limits and Compliance Schedules
    A. Statutory Requirements for Sources for Which EPA Makes a 
Section 126(b) Finding
    B. Proposed Emission Limits
    C. Proposed Compliance Schedules
    D. Alternative Compliance Schedule
IX. 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 (RFA)
    D. Unfunded Mandates Reform Act
    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. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations

II. EPA's Proposed Decision on NJDEP's September 17, 2010 Section 126 
Petition

    EPA is proposing to grant the request in NJDEP's September 17, 
2010, section 126 petition for a finding that emissions from the 
Portland Plant significantly contribute to nonattainment or interfere 
with maintenance of the 1-hour SO2 NAAQS in New Jersey. 
EPA's proposed finding is based on EPA's review of NJDEP's air quality 
modeling, EPA's independent assessment of the AERMOD \1\ dispersion 
modeling, and

[[Page 19664]]

other technical analysis conducted by EPA.
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    \1\ AERMOD stands for the American Meteorological Society/
Environmental Protection Agency Regulatory Model.
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    In granting this request, EPA is also proposing to allow the 
continued operation of the plant and to establish specific emission 
limitations and compliance schedules (including increments of progress) 
to bring the plant into compliance as expeditiously as practicable with 
the CAA prohibition of emissions that significantly contribute to 
nonattainment or interfere with maintenance. EPA is proposing to 
require that the Portland Plant reduce its SO2 emissions to 
a limit no greater than 1,105 lbs/hour for unit 1 and 1,691 lbs/hour 
for unit 2. EPA proposes that the Portland Plant achieve and maintain 
these emission limitations by no later than 3 years after the effective 
date of the final rulemaking. EPA is taking comment on possible interim 
emission reductions such as proposing that the Portland Plant reduce 
its SO2 emissions to a level no greater than 2,910 lbs/hr 
for unit 1, and 4,450 lbs/hr for unit 2, one year after the effective 
date of the final rulemaking, and other compliance activities to 
demonstrate appropriate increments of progress toward compliance. EPA 
has identified a number of existing, proven control technologies, as 
well as operational changes that can be employed to reduce emissions 
from these units. Nevertheless, EPA is also taking comment on an 
alternative compliance option should the Portland Plant decide to cease 
operation at the units subject to the emission limits, and is 
requesting comment on appropriate timeframes and measures for 
increments of progress to include for that alternative compliance 
option. EPA proposes that the emission limits and other measures 
established along with this finding are sufficient to remedy the 
Portland Plant's significant contribution to nonattainment and 
interference with maintenance in the impacted area in New Jersey.

III. Background

A. Section 126 of the Clean Air Act

    The statutory authority for this action is provided by the CAA, 
including but not necessarily limited to, sections 126 and 
110(a)(2)(D)(i).
    Section 126(b) of the CAA provides, among other things, that any 
State or political subdivision may petition the Administrator of 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),\2\ which we describe later in 
detail. 42 U.S.C. 7426(b). Findings by the Administrator, pursuant to 
this section, that a source or group of sources emit 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.
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    \2\ 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).
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    Section 126(c) explains the impact of a section 126 finding and 
establishes the conditions under which continued operation of a source 
subject to such a finding may be permitted. Specifically, section 
126(c) provides that it would be a violation of section 126 of the Act 
and of the applicable State implementation plan: (1) For any major 
proposed new or modified source subject to a section 126 finding to be 
constructed or operate in violation of the prohibition of section 
110(a)(2)(D)(i); or (2) for any major existing source for which such a 
finding has been made to operate more than three months after the date 
of the finding. 42 U.S.C. 7426(c). The statute, however, also gives the 
Administrator discretion to permit the continued operation of a source 
beyond three months if the source complies with emission limitations 
and compliance schedules provided by EPA to bring about compliance with 
the requirements contained in sections 110(a)(2)(D)(i) and 126 as 
expeditiously as practicable but no later than 3 years from the date of 
the finding. Id.
    Section 110(a)(2)(D) of the CAA, often referred to as the ``good 
neighbor'' or ``interstate transport'' provision of the Act, requires 
States to prohibit certain emissions from in-State sources if such 
emissions impact the air quality in downwind States. Specifically, 
section 110(a)(2)(D) requires all States, within 3 years of 
promulgation of a new or revised NAAQS, to submit State implementation 
plans (SIPs) that: contain adequate provisions prohibiting any source 
or other type of emissions activity within the State from emitting any 
air pollutant in amounts which will contribute significantly to 
nonattainment in, or interfere with maintenance by, any other State 
with respect to any such national primary or secondary ambient air 
quality standard, 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. (42 U.S.C. 7410(a)(2)(D)).
    EPA has previously promulgated rules to quantify the specific 
SO2 and nitrogen oxide (NOX) emission reductions 
required in certain eastern States by section 110(a)(2)(D)(i)(I) with 
respect to the NAAQS for ozone and fine particulate matter 
(PM2.5). See 62 FR 57356 (NOX SIP Call); 70 FR 
25162 (CAIR).\3\ EPA has also promulgated Federal rules to directly 
require such reductions. See 71 FR 25318 [finalizing Federal 
Implementation Plans for Clean Air Interstate Rule (CAIR)]; 65 FR 2674 
(making section 126 findings for numerous large EGUs and finalizing a 
remedy for the affected sources). Most recently, EPA proposed the 
Transport Rule to address significant contribution to nonattainment and 
interference with maintenance with respect to the 1997 ozone and the 
1997 and 2006 PM2.5 NAAQS (75 FR 45210). Among other things, 
this proposed rule identifies SO2 and NOX 
reductions that will be needed in certain States to address 
PM2.5 nonattainment and maintenance problems in other 
States. See 75 FR 45129-21 (discussing the air quality problems and the 
specific NAAQS addressed by the proposal). SO2 and 
NOX are identified as the pollutants of concern because of 
their impact on downwind States' ability to attain and maintain the 
PM2.5 and ozone NAAQS. See 75 FR 45237, 45299. 
SO2 and NOX are PM2.5 precursors and 
NOX is also an ozone precursor.
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    \3\ CAIR was subsequently found unlawful and remanded to EPA 
without vacatur, and thus remains in place while EPA responds to the 
remand. See North Carolina v. EPA, 531 F.3d 896, modified on reh'g, 
550 F.3d 1176 (DC Cir. 2006).
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    The problems associated with high levels of SO2 in the 
air, however, are separate and distinct from the problems associated 
with high levels of PM2.5 and are addressed by a separate 
NAAQS, namely the 1-hour SO2 NAAQS. 75 FR 35520 (Primary 
National Ambient Air Quality Standard for Sulfur Dioxide). The 
Transport Rule will not seek to identify or quantify reductions 
necessary to address significant contribution or interference with 
maintenance with respect to the 1-hour SO2 NAAQS. In other 
words, the proposed Transport Rule does not address transport with 
respect to the 1-hour SO2 NAAQS and thus does not address 
the concern raised in NJDEP's section 126 petition. Similarly, State 
110(a)(2)(D)(i) SIP submissions relating to the ozone or 
PM2.5 NAAQS would address only significant contribution to 
nonattainment and interference with maintenance of those NAAQS and thus 
would not address the concerns raised

[[Page 19665]]

regarding significant contribution to nonattainment and interference 
with maintenance of the 1-hour SO2 NAAQS.
    In addition, it is worth noting that the plain language of the 
statute confirms that section 126 remedies can, and in some cases must, 
be promulgated prior to the due date for good neighbor SIPs. Not only 
does section 126 provide a very stringent deadline for EPA to respond 
to section 126 petitions, but section 110(a)(2)(D)(ii) also calls for 
remedies promulgated pursuant to section 126 to be included in the SIP 
submissions that are due 3 years after a NAAQS is promulgated or 
revised. Section 110(a)(2)(D)(ii) requires State SIPs to contain 
adequate provisions ``insuring compliance with the applicable 
requirements of [CAA section 126]''. 42 U.S.C. 7410(a)(2)(D). 
Consistent with the requirement in CAA section 110(a)(1), the 
Commonwealth of Pennsylvania will be required to adopt and submit to 
the Administrator, by June 2013 (3 years after the promulgation of the 
1-hour SO2 NAAQS), a SIP that satisfies the requirements of 
110(a)(2) including the interstate transport requirements of 
110(a)(2)(D)(ii). In other words, the statute requires the State SIP 
submittal to include any emission limits promulgated by EPA pursuant to 
section 126. The fact that Congress required the SIP submittals due 3 
years after promulgation or revision of a NAAQS to include any emission 
limits promulgated pursuant to section 126 is meaningful. If Congress 
had intended to limit EPA's authority to act on section 126 petitions 
until after the deadline for States to submit 110(a)(2)(D)(i) SIPs, it 
could have done so. Instead, it provided a mechanism for section 126 
remedies promulgated prior to the SIP submission deadline to be 
incorporated into the State SIPs. EPA is bound by the language of the 
CAA. Since the statute establishes firm deadlines for action on section 
126 petitions, does not provide an exception for petitions submitted 
prior to the good neighbor SIP submission deadline, and provides a 
mechanism for incorporating reductions required in response to section 
126 petitions into the State SIPs, 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. EPA requests comment 
on this interpretation and all interpretations of section 126 in this 
section.
    EPA has received one prior petition, in 1979, asking for a section 
126 finding with respect to a single source. In this petition, the Air 
Pollution Control District of Jefferson County, Kentucky, requested 
that EPA find, pursuant to the version of section 110(a)(2)(E)(I) of 
the CAA in effect at that time, that emissions from the Gallagher Power 
Station in southern Indiana were preventing attainment and maintenance 
with respect to the 1971 3-hour, 24-hour, and annual SO2 
NAAQS.\4\ 47 FR 6624 (1982). The petition also sought a reduction of 
SO2 emissions from the plant. EPA denied that petition 
basing its decision, in part, on a modeling analysis concluding that 
the Gallagher Power Station's modeled allowable emissions were 
substantially below amounts that would prevent attainment or 
maintenance of the NAAQS. In this proposal, EPA is also using modeling 
analyses to decide whether to make a section 126 finding or deny the 
petition. EPA's decision on the 1979 petition was upheld by the U.S. 
Court of Appeals for the Sixth Circuit.\5\
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    \4\ Section 110(a)(2)(E)(i)(I) of the CAA was superseded by 
110(a)(2)(D)(i)(I) in the 1990 CAA amendments, in part to strengthen 
the prohibitions of interstate transport of emissions (64 FR 28262). 
The relevant wording under 110(a)(2)(E)(i)(I) was changed from 
``prevent attainment or maintenance by any other State'' to 
``contribute significantly to nonattainment in, or interfere with 
maintenance by, any other State'' under 110(a)(2)(D)(i)(I).
    \5\ See Air Pollution Control District of Jefferson County, 
Kentucky v. EPA, 739 F.2d 1071, (U.S. Court of Appeals, Sixth 
Circuit).
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B. Summary of Section 126 Petitions Submitted by NJDEP

1. NJDEP's May 13, 2010 Petition
    On May 13, 2010, EPA received from the NJDEP a section 126 petition 
requesting that EPA make a finding that the Portland Plant is emitting 
air pollutants in violation of the interstate transport provisions of 
the CAA. The petition alleges that emissions from the Portland Plant 
significantly contribute to nonattainment and/or interfere with 
maintenance of the 2006 24-hour PM2.5 NAAQS and the 1971 3-
hour and 24-hour SO2 NAAQS in New Jersey. That petition is 
still under consideration and this action does not address the petition 
submitted on May 13, 2010.
2. NJDEP's September 17, 2010 Petition
    On September 17, 2010, EPA received another section 126 petition 
from NJDEP requesting that EPA make a finding under section 126(b) of 
the CAA that the Portland Plant is emitting air pollutants in violation 
of the interstate transport provisions of the CAA with respect to the 
1-hour SO2 NAAQS promulgated on June 2, 2010 (75 FR 35520). 
NJDEP stated that this petition provided additional documentation to 
supplement the section 126 petition from May 13, 2010.
    NJDEP also submitted a modeling and trajectory analysis to support 
the assertions in the September 17, 2010, petition. This analysis, it 
asserts, demonstrates that the Portland Plant causes violations of the 
1-hour SO2 NAAQS in Warren, Sussex, Morris, and Hunterdon 
Counties in New Jersey. NJDEP's petition asks EPA to directly regulate 
the Portland Plant and requests the installation of appropriate air 
pollution controls, such as a scrubber, which it asserts would provide 
the necessary abatement. As an alternative to address the alleged 
violations, NJDEP's petition suggests that the EPA could impose 
emission limits no less stringent than New Jersey's Reasonably 
Available Control Technology (RACT) rules set forth at N.J.A.C. 7:27-
1.1 et seq.

C. EPA Extensions for Acting on the Section 126 Petition

    Any action taken by EPA under section 126 to make a finding or deny 
a petition is subject to the procedural requirements of CAA section 
307(d). See 42 U.S.C. 7607(d)(1)(N). One of these requirements is 
notice-and-comment rulemaking. See 42 U.S.C. 7607(d)(3). In light of 
the time required for notice-and-comment rulemaking, CAA section 
307(d)(10) provides for a time extension, under certain circumstances, 
for rulemaking subject to section 307(d).
    In accordance with section 307(d)(10), EPA determined that the 60-
day period afforded by section 126(b) for responding to the petition 
from the NJDEP was not sufficient to allow the public and EPA adequate 
opportunity to carry out the purposes of section 307(d). Specifically, 
EPA determined that the 60-day period was insufficient for EPA to 
develop an adequate proposal and allow time for notice-and-comment on 
whether the Portland Plant contributes significantly to nonattainment 
and/or maintenance problems in New Jersey. Based on these 
determinations, on November 16, 2010, EPA published a notice extending 
the deadline for action on the September 17, 2010, petition until May 
16, 2011 (75 FR 69889). In this notice, EPA also explained its 
conclusion that the September 17, 2010, petition submitted by NJDEP is 
a new petition and not a supplement to the May 13, 2010, petition.

D. Background on the Portland Plant and Its Surrounding Area

    The Portland Plant is a 427 megawatt (MW) coal-fired plant located 
in Upper Mount Bethel Township in Northampton County, Pennsylvania. It 
is within 500 feet of Knowlton Township in Warren County, New

[[Page 19666]]

Jersey, directly across the Delaware River. There are two main units, 
unit 1 with a capacity of 160 MW and unit 2 with a capacity of 240 MW. 
There is an auxiliary boiler which burns oil and 3 small turbines 
(units 3, 4, and 5) which all burn oil and natural gas, and have very 
small emissions.
    Units 1, 2, and 5 utilize continuous emissions monitoring system 
(CEMS). In 2009, SO2 emissions combined from units 1 and 2 
at the plant were 30,465 tons and emissions from unit 5 were 0.3 tons 
which are reported from CEMS data. Between 2007 and 2010, units 1 and 2 
operated, on average, approximately 7,000 hours per year. Also, between 
2007 and 2010, unit 5 operated for less than 100 hours per year.\6\
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    \6\ Facility unit data is available at the EPA Clean Air Markets 
Division (CAMD) database available at http://camddataandmaps.epa.gov/gdm/index.cfm?fuseaction=emissions.wizard.
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    The auxiliary boiler, unit 3, and unit 4 do not have CEMS, but 
emissions data are available from the 2008 National Emissions Inventory 
(NEI), Version 1. The auxiliary boiler, unit 3, and unit 4 
SO2 annual emissions reported in the 2008 NEI were 0.01, 
0.02, and 0.03 tons, respectively.
    Other sources of SO2 emissions in the area include the 
Martins Creek facility which is located approximately 10 km to the 
south of the Portland Plant. There are two units at Martins Creek, 
units 3 and 4, which averaged about 1,039 and 584 hours of operation 
respectively. Those units each have a capacity of 850 MW and can burn 
either oil or natural gas. The facility reported approximately 1,100 
tons of SO2 emissions in 2009. There are also three cement 
plants (Hercules, Keystone, and ESSROC) and several minor emitting 
units in Pennsylvania located at distances generally greater than 30 km 
away to the south and west of the Portland Plant. In 2009, the 
Pennsylvania Department of Environmental Protection emission inventory 
database (PADEP eFACTS) reported 1,862 tons for Hercules, 685 tons for 
Keystone, and 799 tons for ESSROC of SO2 emissions 
respectively, all of which are relatively low compared to the 
SO2 emissions from the Portland Plant.
    The Delaware River transects the region, with higher terrain on 
either side of the river valley where the Portland Plant is located. 
There is elevated terrain, as high as or greater than Portland's 
highest stacks, which rises 400 to 500 foot (ft) above the valley floor 
near the Portland Plant. The 1500 ft high Kittatinny Ridge is located 
within 7 kilometer (km) to the north and northwest of the Portland 
Plant. Further south, near the Martins Creek Power Plant, major terrain 
features such as Scotts Mountain to the east of the Delaware River rise 
up to 1000 ft above the valley floor.

E. Sulfur Dioxide and Public Health

    Current scientific evidence links health effects with short-term 
exposure to SO2 ranging from 5 minutes to 24 hours. Adverse 
respiratory health effects include narrowing of the airways which can 
cause difficulty breathing (bronchoconstriction) and increased asthma 
symptoms. These effects are particularly important for asthmatics 
during periods of faster or deeper breathing (e.g., while exercising or 
playing). Studies show an association between short-term SO2 
exposure and increased visits to emergency departments and hospital 
admissions for respiratory illnesses particularly in at-risk 
populations including children, the elderly and asthmatics. EPA's NAAQS 
for 1-hour SO2 is designed to protect against exposure to 
the entire group of sulfur oxides (SOX). SO2 is 
the component of greatest concern and is used to represent the larger 
group of gaseous sulfur oxides. Other gaseous sulfur oxides (e.g., 
SO3) are found in the atmosphere at concentrations much 
lower than SO2. Emissions that lead to high concentrations 
of SO2 generally also lead to the formation of other 
SOX. Control measures that reduce SO2 can 
generally be expected to reduce people's exposure to all gaseous 
SOX. Reducing SO2 emissions is expected to have 
the important cobenefit of reducing the formation of fine sulfate 
particles that pose significant public health threats. SOX 
can react with other compounds in the atmosphere to form small 
particles (e.g., PM2.5). These small particles penetrate 
deeply into sensitive parts of the lungs and can cause or worsen 
respiratory disease, such as emphysema and bronchitis, and can 
aggravate existing heart disease, leading to increased hospital 
admissions and premature death.

IV. EPA's Methodology for Making the Proposed Section 126 Finding for 
the Portland Plant

    This section explains the analysis conducted by EPA to determine 
whether it would be appropriate to find, in response to the petition 
submitted by NJDEP, that the Portland Plant emits or would emit any air 
pollutant in violation of the prohibition of section 110(a)(2)(D)(i)(I) 
with respect to the 1-hour SO2 NAAQS.

A. EPA's Approach for Determining Whether To Make a Section 126 Finding 
for the Portland Plant

1. CAA Section 126(b)
    Section 126 of the CAA provides a mechanism for States and other 
political subdivisions to seek abatement of pollution in other States 
that may be affecting their air quality; however, it does not identify 
specific criteria or a specific methodology for the Administrator to 
apply when deciding whether to make a section 126 finding or deny a 
petition. Therefore, EPA has discretion to identify relevant criteria 
and develop a reasonable methodology for determining whether a section 
126 finding should be made. See, e.g., Chevron, U.S.A., Inc. v. NRDC, 
467 U.S. 837, 842-43 (1984); Smiley v. Citibank, 517 U.S. 735, 744-45 
(1996).
    As an initial matter, EPA looks to see whether a petition 
identifies or establishes a technical basis for the requested section 
126 finding. EPA first evaluates the technical analysis in the petition 
to see if that analysis, standing alone, is sufficient to support a 
section 126 finding. EPA focuses on the analysis in the petition 
because the statute does not require EPA to conduct an independent 
technical analysis to evaluate claims made in section 126 petitions. 
The petitioner thus bears the burden of establishing, as an initial 
matter, a technical basis for the specific finding requested. EPA has 
no obligation to prepare an analysis to supplement a petition that 
fails, on its face, to include an initial technical demonstration. Such 
a petition, or a petition that fails to identify the specific finding 
requested, could be found insufficient. Nonetheless, the Agency may 
decide to conduct independent technical analyses when such analyses are 
helpful in evaluating the basis for a potential section 126 finding or 
developing a remedy if a finding is made. As explained later, given our 
view that it is necessary to make some technical adjustments to the 
NJDEP modeling, we determined that it was appropriate to conduct 
independent technical analysis to determine an appropriate remedy. Such 
analysis, however, is not required by the statute and may not be 
necessary or appropriate in other circumstances.
    In this section, EPA explains the methodology used to evaluate the 
technical analysis presented in NJDEP's petition and to determine 
whether it would be appropriate to make the section 126 finding 
requested. This methodology was developed to address the specific 
allegations in the NJDEP petition and does not speak to how EPA

[[Page 19667]]

might evaluate petitions that raise different interstate transport 
issues, such as collective contributions from multiple sources, 
contributions to nonattainment areas in multiple States, or 
contributions to different NAAQS. The methodology used to assess the 
remedy is discussed in section VII.
2. EPA's Approach To Evaluating NJDEP's Section 126 Petition
    Emissions from upwind States can, alone or in combination with 
local emissions, result in air quality levels that exceed the NAAQS and 
jeopardize the health of residents in downwind communities. Each State 
is required by section 110(a)(2)(D)(i)(I) to prohibit emissions from 
activities within that individual State that would significantly 
contribute to downwind nonattainment or interfere with downwind States' 
maintenance of the NAAQS.
    Section 110(a) of the CAA assigns to each State both the primary 
responsibility for attaining and maintaining the NAAQS within such 
State, and prohibiting emissions activities within the State that will 
significantly contribute to nonattainment or interfere with maintenance 
in a downwind area. States fulfill these CAA obligations through the 
SIP process described in section 110(a) of the CAA. States are required 
to submit SIPs to prohibit those emissions that significantly 
contribute to nonattainment or interfere with maintenance in downwind 
States within 3 years of promulgation of a new or revised NAAQS. See 42 
U.S.C. 7410(a), 7410(a)(2)(D). The prohibition on these emissions is 
intended to assist the downwind State as it designs strategies for 
ensuring that the NAAQS are attained and maintained.
    The NJDEP petition asserts and presents modeling that demonstrates 
that emissions from one plant (the Portland Plant) by itself is 
sufficient to cause downwind SO2 NAAQS violations in New 
Jersey. The approach described later was developed by EPA to analyze 
these specific claims in these particular circumstances and may not be 
appropriate for evaluating other claims or those arising in different 
circumstances for other actions.
    In this case, EPA is proposing to define the Portland Plant'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 the Portland Plant into 
modeled attainment in the analysis year. While this approach would not 
be appropriate in every circumstance, 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. EPA therefore developed a methodology to 
identify the reductions necessary to bring the downwind receptors into 
attainment.
    EPA's methodology uses dispersion modeling to assess the impact of 
emissions from the Portland Plant on SO2 concentrations at 
downwind receptors. EPA modeled the emissions from the Portland Plant 
and determined that the modeled concentrations from the Portland Plant, 
when combined with the relatively low background concentrations [in the 
manner described in section VII and in greater detail in the Modeling 
Technical Support Document (TSD)], cause violations of the 1-hour 
SO2 NAAQS in New Jersey. We have determined it is 
appropriate to use modeling in this case to determine whether downwind 
air quality will attain the 1-hour SO2 NAAQS in the analysis 
year.\7\
---------------------------------------------------------------------------

    \7\ Historically, EPA has favored dispersion modeling to support 
SO2 NAAQS compliance determinations for areas with 
sources that have the potential to cause an SO2 NAAQS 
violation, and EPA explained that for an area to be designated as 
``attainment,'' dispersion modeling regarding such sources needs to 
show the absence of violations even if monitoring does not show a 
violation. This has been our general position throughout the history 
of implementation of the SO2 NAAQS program. See 75 FR 
35551.
---------------------------------------------------------------------------

    In the modeling analysis, thousands of receptors are placed in New 
Jersey to determine the area of maximum concentration from the Portland 
Plant emissions. A design value concentration is calculated for each 
receptor for comparison to the NAAQS. The design value concentration is 
equal to the 99th percentile (4th-highest) daily maximum 1-hour 
SO2 concentration. All receptors with modeled design value 
concentrations that are greater than the NAAQS (196 [mu]g/m\3\) are 
determined to be nonattainment receptors.
    To quantify the emissions that constitute the Portland Plant's 
significant contribution, we identify the level of emissions that need 
to be reduced to ensure that no modeled concentration within the 
affected area exceeds the level of the NAAQS (i.e., the 99th percentile 
of the daily maximum 1-hour average of 196 [mu]g/m\3\).
    The first step of the ``interfere with maintenance'' analysis is to 
identify whether there are any maintenance receptors in the relevant 
area. In considering maintenance, we are examining the receptors in the 
analysis to determine if higher modeled concentrations may exist due to 
variability in meteorology, emissions, and/or other factors. 
Nonattainment receptors are already modeled to be above the NAAQS and 
receptors with higher \8\ concentrations attributed to variability in 
emissions or meteorology would be exceeding the NAAQS by an even 
greater amount. Therefore, nonattainment receptors are by definition 
also maintenance receptors. In addition to these nonattainment/
maintenance receptors, we also examine receptors that are modeled to be 
attainment but due to variability in meteorology or emissions might be 
at risk for nonattainment. In that case, any identified maintenance 
receptors would not be nonattainment and would therefore be considered 
``maintenance only'' receptors.
---------------------------------------------------------------------------

    \8\ Variability of emissions and meteorology could also lead to 
lower concentrations; however, for purposes of identifying 
interference with maintenance receptors, we would only be concerned 
with concentrations that would be higher than those modeled.
---------------------------------------------------------------------------

    In this particular case, due to the high modeled concentrations 
from the Portland Plant emissions, all of the downwind modeled 
receptors in the 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 centered on the 
receptors with the maximum impact from the Portland Plant. In a primary 
pollutant dispersion modeling application, emissions reductions from 
the contributing source lead to a linear reduction in downwind 
concentrations. Therefore, we can be certain that an emissions limit on 
the Portland Plant that eliminates modeled violations at the maximum 
concentration receptor will eliminate violations at all potential 
receptors. Because there are no ``maintenance only'' receptors in the 
area of concern, it was not necessary for us to consider the Portland 
Plant's impact on maintenance only receptors.
    We next consider whether the Portland Plant 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 at the nonattainment/maintenance 
receptors. We identified an approach that we believe is appropriate for 
the specific circumstances presented here.
    Among other things, we considered the nature of the modeling used 
to determine the appropriate remedy and the potential for 
SO2 concentrations in New Jersey to be higher than those

[[Page 19668]]

modeled. Here are some of the relevant facts:
    (1) There is only 1 year of site-specific meteorology available for 
this analysis, so we are not able to 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 allowable emissions from the Portland 
Plant. 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 emissions from the Portland Plant.
    (3) In the modeling analysis, we used a seasonal and hourly varying 
background concentration that represents the high end of the 
distribution (99th percentile) of hourly observed SO2 
concentrations in the area. As indicated in the trajectory analysis 
submitted by NJDEP, it is likely that direct SO2 impacts 
from the Portland Plant contributed to high monitored concentrations at 
the monitor located in Chester, New Jersey (Chester monitor). 
Therefore, to avoid double counting of contributions from the Portland 
Plant through both monitored and modeled emissions, it would not be 
appropriate to consider higher background concentrations.
    EPA believes that given the specific circumstances described 
previously, there is no indication that concentrations higher than 
those modeled from the Portland Plant would be likely to occur at the 
nonattainment/maintenance receptors or anywhere in New Jersey. It is 
therefore reasonable to conclude, under the circumstances, that any 
remedy that eliminates the significant contribution to nonattainment 
from the Portland Plant will also eliminate its interference with 
maintenance with respect to year-to-year variability in emissions and 
air quality.
    As noted in the proposed Transport Rule, EPA believes that the 
maintenance concept has two components: Year-to-year variability in 
emissions and air quality, and continued maintenance of the air quality 
standard over time. Consistent with the approach in the Transport Rule, 
EPA examined both of these concepts in assessing ``interfere with 
maintenance'' for NJDEP's section 126 petition regarding the Portland 
Plant. Year-to-year variability is discussed above. Year-to-year 
variability is appropriate to consider because data demonstrates that 
year-to-year variations in air quality that stem from differences in 
weather and emissions can determine whether or not the health-based 
standard will be achieved in a particular location in the analyzed 
year.
    EPA separately considered whether further emissions reductions from 
the Portland Plant are necessary to ensure continued lack of 
interference with maintenance of the NAAQS over time, and believes that 
the answer is no. The proposed requirements of this rule will prevent 
the emissions of the Portland Plant from increasing over time relative 
to the modeled scenario. Also, EPA does not have evidence that 
background SO2 emissions from other sources affecting the 
relevant New Jersey receptors will increase in the future, which--in 
combination with residual Portland Plant emissions--in theory might 
have raised the possibility of a future maintenance issue at those 
receptors.
    In conclusion, we are proposing to find that compliance by the 
Portland Plant with the emission limits proposed in this action 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.
    EPA requests comment on our approach to address interference with 
maintenance with regard to this specific petition and whether the 
proposed emission limits are sufficient to eliminate the Portland 
Plant's interference with maintenance of the 1-hour SO2 
NAAQS in New Jersey.

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

A. Summary of the Modeling Submitted by NJDEP To Support the Petition

    NJDEP submitted several technical analyses in support of its 
section 126 petition. Among the submitted materials were a summary of 
the NJDEP dispersion modeling results, a modeling analysis for the 1-
hour SO2 NAAQS using AERMOD, a modeling analysis for the 1-
hour SO2 NAAQS using CALPUFF,\10\ and a trajectory analysis 
of high SO2 episodes at a SO2 monitor in Chester, 
New Jersey. In addition, the petition references a CALPUFF model 
validation study, which was submitted by NJDEP along with the previous 
(May 13, 2010) section 126 petition.
---------------------------------------------------------------------------

    \10\ CALPUFF is a non-steady-state puff dispersion model that 
was originally developed for the California Air Resources Board.
    \11\ NJDEP did not add background concentrations to any of the 
modeled concentrations in the table.
    \12\ Meteorological data used in the AERMOD modeling was based 
on the only site-specific meteorological data available for the 
Portland Plant, from July 1993 through June 1994, which satisfies 
the recommendations in Section 8.3.1 of Appendix W regarding the 
length of record for meteorological data.
---------------------------------------------------------------------------

    NJDEP submitted two different modeling analyses of the 
SO2 impacts from the Portland Plant on New Jersey. The first 
analysis (Exhibit 2 to the NJDEP petition) used the AERMOD dispersion 
model and the second analysis (Exhibit 3 to the NJDEP petition) used 
the CALPUFF dispersion model. Both models were run with both actual and 
allowable emissions rates and CALPUFF was also run with various 
meteorological input data. Each NJDEP model run showed modeled 
violations of the 1-hour SO2 NAAQS (i.e., showed annual 99th 
percentile of daily maximum 1-hour SO2 values at or above 
196 [mu]g/m\3\) in New Jersey.
    Table V.A-1 summarizes the CALPUFF and AERMOD 1-hour SO2 
NAAQS (196 [mu]g/m\3\, 99th percentile) modeling results submitted by 
NJDEP.

                           Table V.A-1--Summary of Modeling Results Submitted by NJDEP
----------------------------------------------------------------------------------------------------------------
                                                                                                       99th
                                                                                                    Percentile
                                                                                      Maximum       (4th high)
               Model                      Emissions             Meteorology           modeled         modeled
                                                                                   concentration   concentration
                                                                                   ([mu]g/m\3\)    ([mu]g/m\3\)
                                                                                                       \11\
----------------------------------------------------------------------------------------------------------------
AERMOD............................  Allowable............  July 1993-June 1994             3,700           1,402
                                                            \12\.
AERMOD............................  Estimated Actual.....  July 1993-June 1994..           1,713           467.3
CALPUFF...........................  Allowable............  2002 12km MM5........          15,273           3,455

[[Page 19669]]

 
CALPUFF...........................  Actual...............  2002 12km MM5........           6,740           2,194
CALPUFF...........................  Allowable............  2003 4km MM5.........          18,643           2,468
----------------------------------------------------------------------------------------------------------------

    As can be seen in the table V.A-1, each of the modeling analyses 
submitted by NJDEP shows modeled violations of the 1-hour 
SO2 NAAQS. The concentrations predicted by the CALPUFF model 
tend to be higher than those predicted by the AERMOD model. In 
addition, the model runs based on allowable emissions logically show 
higher concentrations than those based on actual emissions. The 
allowable emissions included in the NJDEP modeling are shown in Table 
V.A-2.

                               Table V.A-2
------------------------------------------------------------------------
                                                           Maximum 3-hr
                                           Allowable SO2   permit limit
           Portland Plant unit             rate  (lb/hr)    (tons per 3
                                                              hours)
------------------------------------------------------------------------
1.......................................           5,820            8.73
2.......................................           8,900           13.35
------------------------------------------------------------------------

    The petition also contained modeling of actual emissions for the 
2002 MM5 (mesoscale meteorological model) based CALPUFF case and this 
modeling run showed large exceedances of the 1-hour SO2 
NAAQS. Actual emissions were also modeled with AERMOD for the 1993-1994 
site-specific meteorology. As with the modeling based on allowable 
emissions, the AERMOD results with actual emissions were much lower 
than the CALPUFF results, but still showed significant exceedances of 
the 1-hour SO2 NAAQS. The 2002 CALPUFF modeling with actual 
emissions was based on actual SO2 emissions from CEMS data. 
The 1993-1994 actual emissions used with AERMOD were estimated based on 
monthly coal usage reports (CEMS data were not available for that 
period).
    The modeling submitted by NJDEP indicates actual emissions from the 
Portland Plant alone cause air quality in New Jersey to exceed the 1-
hour SO2 NAAQS. The NJDEP modeling also indicates that the 
Portland Plant's allowable emissions (i.e., the emissions the plant 
would emit if it were to emit at the level currently allowed) cause air 
quality in New Jersey to exceed the 1-hour SO2 NAAQS. The 
NJDEP AERMOD predictions of the 4th high daily 1-hour maximum 
concentrations (99th percentile) based on allowable emissions show a 
maximum concentration in New Jersey of 1,402 [mu]g/m\3\ (located on a 
ridge at the Delaware Water Gap (in New Jersey) approximately 7 
kilometers (km) from the Portland Plant stacks). The AERMOD modeling 
submitted by NJDEP also demonstrates that actual emissions from the 
Portland Plant are causing NAAQS exceedances in New Jersey. In 
addition, the CALPUFF predictions of the 4th high daily maximum 1-hour 
concentrations (99th percentile) based on allowable emissions are as 
high as 3,455 [mu]g/m\3\.
    The results of the NJDEP modeling based on both allowable and 
actual emissions indicate that emissions reductions would be needed at 
the Portland Plant in order to eliminate Portland's significant 
contribution to nonattainment in New Jersey.

B. EPA's Assessment of Modeling Submitted by NJDEP

    EPA evaluated several aspects of the NJDEP modeling to determine if 
the analyses followed EPA regulations and guidance for dispersion 
modeling. Among the key specific issues evaluated were the choice of 
model(s), modeling of actual vs. allowable emissions, and the 
application of site-specific meteorological data that were used as 
inputs to the AERMOD model. Additional technical details regarding the 
NJDEP modeling were also examined, as documented in the Modeling TSD.
1. NJDEP's Model Selection
    EPA first evaluated which model is most appropriate for use in 
these particular circumstances. As noted previously, NJDEP submitted 
both AERMOD and CALPUFF model results. Given the significant 
differences in the magnitude of predicted impacts associated with the 
Portland Plant emissions based on the use of the AERMOD model versus 
use of the CALPUFF model, identifying the most appropriate model for 
use in these circumstances was a key aspect of EPA's assessment. 
Section 4.2.2(b) of the ``Guideline on Air Quality Models,'' published 
as Appendix W to 40 CFR Part 51 (commonly referred to as ``Appendix 
W'') States that AERMOD is ``the recommended model'' ``[f]or a wide 
range of regulatory applications in all types of terrain.'' \13\ The 
modeling application under consideration in this section 126 petition 
is covered under this section of Appendix W since the transport 
distances of concern are less than 50 kilometers.
---------------------------------------------------------------------------

    \13\ Section 4.2.2 identifies other models that are recommended 
for specific applications that do not apply for the Portland Plant, 
e.g., the Buoyant Line and Point Source (BLP) dispersion model is 
recommended for cases where buoyant plume rise from line sources is 
important.
---------------------------------------------------------------------------

    The NJDEP petition acknowledges that AERMOD is the preferred model 
for near-field applications such as this, but suggests 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, as follows:
    (1) If a demonstration can be made that the model produces 
concentration estimates equivalent to the estimates obtained using a 
preferred model;

[[Page 19670]]

    (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; or
    (3) If the preferred model is less appropriate for the specific 
application, or there is no preferred model.
    The NJDEP modeling documentation suggests that NJDEP's use of the 
CALPUFF model in support of this petition is based on condition (2) of 
Section 3.2.2b. NJDEP claims that CALPUFF was shown to have ``performed 
better and produced predictions of greater accuracy than AERMOD,'' \14\ 
and therefore satisfies condition (2) under Section 3.2.2b of Appendix 
W. NJDEP also claims that the use of CALPUFF is more appropriate for 
the specific application due to the complex winds addressed in Section 
7.2.8 of Appendix W \15\ and is therefore justified under condition (3) 
of Section 3.2.2b.
---------------------------------------------------------------------------

    \14\ See September 17, 2010 petition, Section IV, page 5.
    \15\ See May 13, 2010, petition, Section V, subsection B.
---------------------------------------------------------------------------

    For the reasons stated later, EPA determines that AERMOD is the 
appropriate modeling platform to use in these specific circumstances. 
This conclusion is based on the particular circumstances presented here 
and does not speak to whether it would be appropriate to use CALPUFF 
modeling in other situations.
a. CALPUFF Alternative Model Justification
    EPA issued a memo on August 13, 2008, providing ``Clarification of 
Regulatory Status of CALPUFF for Near-field Applications,'' \16\ (which 
applies to the application under review here). The key points 
emphasized in that memo are as follows:
---------------------------------------------------------------------------

    \16\ ``Clarification of Regulatory Status of CALPUFF for Near-
field Applications,'' memo from Richard A. Wayland, dated August 13, 
2008, available at http://www.epa.gov/ttn/scram/clarification%20of%20regulatory%20status%20of%20calpuff.pdf.
---------------------------------------------------------------------------

    1. The EPA-preferred model for near-field regulatory applications 
(less than 50 kilometers) for simple and complex terrain is AERMOD. The 
AERMOD model should be used for all near-field regulatory applications, 
unless an adequate determination is made that AERMOD is not appropriate 
for that application or is clearly less appropriate than an alternative 
model.
    2. CALPUFF is not the EPA-preferred model for near-field 
applications, but may be considered as an alternative model on a case-
by-case basis for near-field applications involving ``complex winds,'' 
subject to approval by the reviewing authority. The approval of CALPUFF 
for near-field regulatory applications must be based on case-specific 
justification, including necessary documentation and an adequate 
determination that AERMOD is not appropriate or clearly less 
appropriate than CALPUFF.
    The impacts from a source such as the Portland Plant (tall stacks 
with nearby terrain features) are likely to occur with ``line-of-
sight'' impacts of the elevated plumes on nearby terrain features for 
which straight-line, steady-state assumptions are valid.
    The AERMOD model has been evaluated for similar situations of tall 
stacks in complex terrain settings for at least five separate data 
bases and consistently shown to perform better than competing models 
(Perry, et al., 2005; \17\ EPA, 2003 \18\). Therefore, EPA does not 
agree with the argument that CALPUFF is more appropriate in this 
situation due to the existence of complex winds.
---------------------------------------------------------------------------

    \17\ Perry, S.G., A.J. Cimorelli, R.J. Paine, R.W. Brode, J.C. 
Weil, A. Venkatram, R.B. Wilson, R.F. Lee, and W.D. Peters, 2005. 
AERMOD: A Dispersion Model for Industrial Source Applications. Part 
II: Model Performance against 17 Field Study Databases. J. Appl. 
Meteor., 44, pp. 694-708.
    \18\ EPA, 2003. AERMOD: Latest Features and Evaluation Results. 
EPA-454/R-03-003. U.S. Environmental Protection Agency, Research 
Triangle Park, NC, available at http://www.epa.gov/scram001/7thconf/aermod/aermod_mep.pdf.
---------------------------------------------------------------------------

    We thus turn to NJDEP's assertion that the use of CALPUFF as an 
alternative model can be justified under condition (2) of Section 
3.2.2b, based on a demonstration that CALPUFF performs better than 
AERMOD. To evaluate this assertion, we evaluate whether there is 
evidence to support NJDEP's assertion that CALPUFF performs better than 
AERMOD. In the September 17, 2010, petition, NJDEP references a CALPUFF 
validation study that was submitted with the May 13, 2010, petition. 
EPA believes it is appropriate to consider this study because it was 
explicitly referenced in the September 17, 2010, petition, and a copy 
was provided with the prior petition.
    We note again that the AERMOD model has undergone extensive peer 
review and model validation as the basis for its promulgation as the 
preferred model for a wide range of regulatory applications in all 
types of terrain. Therefore, we would not determine CALPUFF to be a 
more appropriate model in this case absent compelling evidence that 
CALPUFF is clearly superior to AERMOD for this application.
    Model validation is a complex process that entails several 
technical challenges, including uncertainties regarding the accuracy 
and representativeness of key input data that could affect results, as 
well as a wide range of statistical methods and metrics that may be 
applied to quantify model performance. In some cases subtle changes to 
the evaluation methods can markedly affect the conclusions that might 
be drawn from such studies. For these reasons, the importance of 
establishing a consistent set of objective procedures to evaluate the 
performance of dispersion models for use in regulatory modeling 
applications and of comparing the relative performance of competing 
models has long been recognized. Section 3.2.1 of Appendix W references 
EPA's ``Protocol for Determining the Best Performing Model'' \19\ 
document (EPA, 1992) that states it ``is available to assist in 
developing a consistent approach when justifying the use of other-than-
preferred modeling techniques recommended in the Guideline. The 
procedures in this protocol provide a general framework for objective 
decision-making on the acceptability of an alternative model for a 
given regulatory application.
---------------------------------------------------------------------------

    \19\ ``Protocol for Determining the Best Performing Model'', 
EPA-454/R-92-025, December 1992. U.S. Environmental Protection 
Agency, Research Triangle Park, NC, available at http://www.epa.gov/ttn/scram/guidance/guide/modleval.zip.
---------------------------------------------------------------------------

    Although the CALPUFF validation study submitted by NJDEP with the 
May 13, 2010, petition cites EPA's Protocol as one of the references 
for its model validation procedures, there were some key changes 
implemented in the NJDEP model evaluation study relative to the methods 
recommended and used by EPA in its evaluation of AERMOD model 
performance. EPA's evaluation of NJDEP's changes to the protocol leads 
us to believe that the NJDEP methods show relatively better model 
performance for CALPUFF compared to AERMOD, without any clear technical 
basis that would justify those changes. Further details on these 
changes and their impacts on the results of the validations study are 
provided in the Modeling TSD included in the docket for this 
rulemaking.
    Furthermore, the Quantile-Quantile (Q-Q) plots \20\ included in the 
NJDEP validation report provide a clear visual representation of model 
performance that is very relevant to the regulatory application of 
these models. These plots suggest that the performance of the

[[Page 19671]]

CALPUFF and AERMOD models on this database is in fact quite similar, 
but that AERMOD shows slightly better overall agreement with 
observations.
---------------------------------------------------------------------------

    \20\ Quantile-Quantile (Q-Q) plots compare modeled vs. monitored 
concentrations on the basis of independently ranked distributions of 
concentration, unpaired in time and space.
---------------------------------------------------------------------------

    Another fundamental point in relation to NJDEP's overall 
justification for the use of CALPUFF in this petition is that results 
from the model validation study are not relevant to this application of 
CALPUFF due to fundamental differences in the meteorological processing 
used in the validation study compared to the modeling submitted in 
support of the petition. The CALMET modeling for the validation study 
made use of the site-specific meteorological data collected as part of 
the field study so that the documented CALPUFF model performance is 
largely dependent on the characterization of wind fields by CALMET that 
are informed by that site-specific data. In contrast, the application 
of CALPUFF to support the petition did not use any site-specific 
meteorological data but relied on three different sets of MM5 
prognostic meteorological data to inform the 3-dimensional wind fields 
generated by CALMET. Performance of the CALPUFF model in this case 
would rely upon the ability of the CALMET meteorological model to 
adequately simulate the wind fields in the absence of such site-
specific data, and there have not been any such demonstrations that 
would be relevant to this application.
    We also note that the spatial distribution of 1-hour SO2 
impacts predicted by CALPUFF (in the petition application) is very 
different than the impacts predicted by AERMOD. The CALPUFF modeling 
shows extremely high 1-hour SO2 concentrations very close to 
the Portland Plant (see Figures 1, 2, and 3 of Exhibit 3). The highest 
impacts based on the 2002 CALPUFF modeling with allowable emissions of 
3,455 [mu]g/m\3\ (99th percentile of daily maximum 1-hour values) 
occurs about 100 meters from units 1 and 2 at an elevation of only 3 
meters above the stack base in Pennsylvania. These results are 
physically unrealistic for buoyant plumes from tall stacks such as 
units 1 and 2 at the Portland Plant, raising additional concerns 
regarding the appropriateness of CALPUFF for this application.
    Based on the discussion previously (and additional details 
contained in the Modeling TSD), we conclude that NJDEP has not 
adequately justified the use of CALPUFF in this application under 
either conditions (2) or (3) of Section 3.2.2b of Appendix W, and that 
AERMOD is the most appropriate model for this application.\21\
---------------------------------------------------------------------------

    \21\ EPA's discussion of the appropriate air quality model for 
near field applications focuses on primary emissions from a 
stationary source, such as the SO2 emissions from the 
Portland Plant, at issue in NJDEP's petition. EPA is not suggesting 
that AERMOD is the appropriate model to simulate the effects of 
SO2 and nitrogen oxide emissions on secondary pollutants 
formed in the atmosphere such as PM2.5 and ozone. See 70 
FR 68,234.
---------------------------------------------------------------------------

2. Emissions and Source Characteristics
    As noted previously, NJDEP submitted dispersion modeling results 
based on maximum allowable emissions as well as actual emissions. For 
the reasons explained later, EPA has determined that it is reasonable 
and appropriate to model allowable emissions when evaluating whether 
the source ``emits or would emit'' any air pollutant in violation of 
the prohibition of section 110(a)(2)(D)(i) under a section 126 
petition. EPA interprets the term ``emits or would emit'' as a 
reference to the source's current and potential future emissions. A 
determination of whether the source ``emits'' pollutants in violation 
of the prohibition of section 110(a)(2)(D)(i) could be based on 
modeling of actual emissions. However, for the emissions the source 
``would emit'' (i.e., its potential future emissions), it is 
appropriate to consider the level at which the source could emit given 
the existing constraints on its emissions--that is, the source's 
allowable emissions.
    For these same reasons, EPA believes it appropriate to model 
allowable emissions when determining the appropriate remedy to 
eliminate the source's significant contribution to nonattainment and 
interference with maintenance. In addition, as a practical matter, it 
would be difficult to determine an appropriate remedy under a section 
126 petition based on actual emissions given the potential variability 
of actual emissions. Because the question posed is what additional 
limits must be placed on the source's emissions to eliminate its 
significant contribution to nonattainment and interference with 
maintenance, it is appropriate to consider what its emissions could be 
in the absence of such limits.
    For these reasons, the rest of the review of NJDEP's modeling and 
the methodology of EPA's remedy modeling is limited to modeled results 
based on allowable emissions.
3. Meteorological Data
    Aside from emissions data, meteorological data are the other key 
input to dispersion models. The NJDEP AERMOD modeling was based on 1 
year of site-specific meteorological data collected from a 100-meter 
instrumented tower and sonic detection and ranging (SODAR) system 
located about 2.2 kilometers west of the Portland Plant, for the period 
July 1993 through June 1994.
    Section 8.3 of Appendix W provides guidance regarding 
meteorological data for use in dispersion modeling to demonstrate 
compliance with the NAAQS. A key issue related to meteorological data 
is the representativeness of the data for the particular application, 
including spatial and temporal representativeness. Based on a review of 
the data, we believe that the meteorological data from 1993-1994 \22\ 
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 the Portland 
Plant's units 1 and 2. The 1993-1994 data also meet the minimum 
criterion of at least 1 year of site-specific meteorological data 
recommended in Section 8.3.1.2(b) of Appendix W.
---------------------------------------------------------------------------

    \22\ The fact that the 1993-1994 meteorological data is nearly 
20 years old is not relevant. The modeling was conducted with 
allowable emissions from the Portland Plant. The meteorology needs 
to be representative of typical meteorology that occurs in the area, 
regardless of time period. The allowable emissions do not vary, 
regardless of the meteorological data year.
---------------------------------------------------------------------------

    Although the Portland Plant meteorological data meet the basic 
criteria for representativeness, we note that there is a difference of 
about 100 meters between the base elevation for the meteorological 
tower and that of the stack base elevation. This raises concerns 
regarding how the meteorological data were input to the AERMOD model in 
the NJDEP modeling analysis, especially 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 modeling submitted by NJDEP used the measurement heights above 
local ground for the meteorological data input to the model, 
effectively assuming that the measured profiles of wind, temperature 
and turbulence were ``terrain-following.''
    We provide additional analysis of the impact on the tower height in 
the EPA remedy modeling section and in the Modeling TSD. We believe an 
adjustment to the meteorological data heights is warranted and EPA made 
these adjustments in the supplemental technical analysis it conducted 
to determine the appropriate remedy. These adjustments may play an

[[Page 19672]]

important role in determining the remedy, as explained later in section 
VII. However, since the maximum design value concentration in the NJDEP 
AERMOD modeling analysis was nearly seven times the NAAQS, we do not 
expect these adjustments to change the overall conclusion that the 
Portland Plant emissions are likely to cause or contribute to 
violations of the 1-hour SO2 NAAQS in New Jersey.
4. Receptor/Terrain Data
    Proper treatment of terrain information is important for this 
analysis given the potential influence of elevated and complex terrain 
on the modeling results. The NJDEP analysis was based on an initial 
grid of coarsely spaced receptor locations across a large domain 
covering all potentially important impact areas associated with 
emissions from the Portland Plant, followed by a much smaller grid of 
more closely spaced receptors focused on the area of expected worst-
case impacts from the plant. The initial grid included spacing of 250 
meters in areas of expected high impacts with receptors spaced at 1,000 
meter intervals covering the gaps between the 250-meter grids. The 
initial coarse receptor grid included a total of 5,189 receptors. The 
fine grid used by NJDEP in determining the controlling impact from the 
Portland Plant for purposes of this petition included a total of 121 
receptors in a 10 x 10 array spaced at 100-meter intervals covering a 
portion of the Kittatinny Ridge on the New Jersey side of the Delaware 
Water Gap.
5. AERMOD Results
    NJDEP's AERMOD modeling shows maximum design value impacts from the 
Portland Plant, based on allowable SO2 emissions of 1402 
[mu]g/m\3\ in New Jersey.\23\ Since those concentrations are nearly 
seven times the 1-hour SO2 NAAQS (196 [mu]g/m\3\), and since 
NJDEP's AERMOD modeling also showed significant exceedances of the 1-
hour SO2 NAAQS in NJ based on an estimate of actual 
SO2 emissions, we conclude that the NJDEP has clearly shown 
that SO2 emissions from the Portland Plant cause violations 
of the 1-hour SO2 NAAQS in New Jersey.
---------------------------------------------------------------------------

    \23\ The 1402 [mu]g/m\3\ impact from the Portland Plant did not 
include background concentrations. In most modeling applications, a 
representative background concentration would be added to the 
modeled concentrations from the source being modeled. But since the 
modeled concentration from the Portland Plant exceeded the NAAQS, 
accounting for background does not make a difference to the finding 
of violations. However, assumed background concentrations are needed 
for the remedy modeling which is discussed in section VII.
---------------------------------------------------------------------------

C. Summary of NJDEP's Trajectory Analysis and the Columbia Lake Monitor

    As a supplement to its supporting modeling analyses, NJDEP analyzed 
winds using a trajectory model on days with the highest concentrations 
of SO2 at a State operated ambient air monitoring site in 
Chester, Morris County, New Jersey. NJDEP used the HYSPLIT \24\ model 
to calculate the movement of air during these two episodes, which 
covered three days (July 17-18, 2008 and December 7, 2009). The 
monitoring site in Chester is about 36 kilometers east-southeast of the 
Portland Plant. Concentrations of SO2 on one of these days 
exceeded the 1-hour SO2 NAAQS of 75 parts per billion (ppb). 
The trajectories generated by HYSPLIT show that air from the Portland 
Plant arrives in the vicinity of Chester about the time of the highest 
concentrations of SO2, shown by running the model in two 
modes: Forward from the facility and backward from the monitoring site. 
When these high concentrations occurred, a review of available 
emissions data showed that no other facility in the area had emissions 
more than 1/1,000th the emissions of the Portland Plant. NJDEP asserts 
that this trajectory analysis demonstrates that it is likely that the 
Portland Plant is largely responsible for these recorded high 
concentrations.
---------------------------------------------------------------------------

    \24\ The Hybrid Single-Particle Lagrangian Integrated Trajectory 
(HYSPLIT) model computes simple air parcel trajectories using a 
three-dimensional grid. NJDEP used the HYSPLIT model using an ETA 
meteorological model with a 12 km horizontal grid size for the 
three-dimensional grid. See http://ready.arl.noaa.gov/ for more 
details on the HYSPLIT.
---------------------------------------------------------------------------

    We also note that 1-hour SO2 monitoring data have been 
collected since September 23, 2010, at the NJDEP Columbia Lake Wildlife 
Management Area (WMA) air quality monitor in Knowlton Township, Warren 
County, New Jersey, located about 2 km northeast of the Portland Plant, 
that show several exceedances of the 1-hour SO2 NAAQS. The 
exceedances are shown during periods when prevailing winds (as measured 
at the Allentown International Airport) would disperse emissions from 
the Portland Plant in the general direction of the Columbia monitor.

VI. EPA's Decision on Whether To Make a Section 126 Finding or Deny the 
Petition

    Based on the results of the NJDEP modeling described previously, 
EPA is proposing to grant the request in NJDEP's September 17, 2010, 
petition that EPA make a finding that emissions from the Portland Plant 
significantly contribute to nonattainment or interfere with maintenance 
of the 1-hour SO2 NAAQS.
    As explained previously, NJDEP conducted dispersion modeling of the 
1-hour SO2 impacts using both the CALPUFF and AERMOD 
dispersion models. 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 the Portland Plant. For the reasons explained 
previously and in the TSD in the docket for this rulemaking, EPA 
believes that the AERMOD analysis, submitted by NJDEP, provides a 
reasonable basis for analyzing whether or not emissions from the 
Portland Plant significantly contribute to nonattainment or interfere 
with maintenance in Warren, Sussex, Morris, and Hunterdon Counties in 
New Jersey. EPA has determined 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 Modeling TSD. 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.
    In addition, the trajectory analysis submitted from NJDEP and the 
preliminary air quality monitoring data collected from the Columbia 
monitor in New Jersey are consistent with our proposed finding of 
significant contribution to nonattainment and interference with 
maintenance of the 1-hour SO2 NAAQS in New Jersey. A 
detailed review of the trajectory and monitoring data is included in 
the Trajectory Analysis of High Sulfur Dioxide Episodes TSD, and the 
Columbia Monitor in Warren County TSD contained in the docket for this 
proposal.

VII. EPA's Proposed Remedy

A. Quantification of the Emission Reductions Necessary To Eliminate the 
Portland Plant's Significant Contribution

    EPA next conducted analyses to determine an appropriate remedy, as 
required by section 126.
    In the section 126 petition, NJDEP suggested that appropriate 
remedies for the Portland Plant might be installation of scrubbers or 
meeting the RACT limit that New Jersey has set for SO2 
sources in its State. EPA's authority under section 126, however, is 
limited to

[[Page 19673]]

establishing emission limits and compliance schedules (including 
increments of progress) as needed to bring the Portland Plant into 
compliance as expeditiously as practicable. EPA cannot apply New Jersey 
law extraterritorially in Pennsylvania. In addition, we believe it is 
better policy for EPA, where only directed by statute to provide 
emission limits and compliance schedules, to allow the source the 
flexibility to achieve compliance in the way it determines is most 
reasonable and not to require the use of a specific technology.
    Because section 126 allows continued operation of a major existing 
source subject to a section 126 finding, only if the source complies 
with emission limits and compliance schedules established by 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 date of the finding. Thus, to determine 
the appropriate remedy, EPA must quantify the reductions necessary to 
eliminate the Portland Plant's significant contribution to 
nonattainment and interference with maintenance of the 1-hour 
SO2 NAAQS in New Jersey.
    We previously determined that due to the magnitude of the modeled 
violations in the NJDEP AERMOD modeling, the NJDEP modeling was 
sufficient to make a finding that the Portland Plant significantly 
contributes to nonattainment and interferes with maintenance in New 
Jersey. 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, EPA conducted an independent modeling assessment to 
help determine the necessary and appropriate emissions limit for 
Portland units 1 and 2.
1. Summary of EPA's Remedy Modeling for 1-Hour SO2 NAAQS
    EPA completed AERMOD modeling of the Portland Plant units 1, 2, and 
5 using the 1993-1994 Portland Plant on-site meteorological data. EPA 
made several adjustments to the meteorological inputs (compared to the 
NJDEP modeling) which it determined to be appropriate, as documented in 
the Modeling TSD. The maximum modeled design value impact from the 
Portland Plant in New Jersey based on EPA's modeling was 851.1 [mu]g/
m\3\. This included an impact from the Portland Plant of 811.8 [mu]g/
m\3\ plus a background concentration of 39.3 [mu]g/m\3\. The details of 
the modeling setup are summarized later and in greater detail in the 
Modeling TSD, which is in the docket for this proposal.
2. Model Selection
    As discussed in Section V.B of this notice, Appendix W, Section 
4.4.2(b) states that AERMOD is ``the recommended model'' ``[f]or a wide 
range of regulatory applications in all types of terrain.'' The 
modeling application under consideration in this section 126 petition 
is generally covered under this section of Appendix W since the 
transport distances of concern are less than 50 kilometers. Therefore, 
EPA used AERMOD to determine the necessary remedy to eliminate the 
significant contribution to nonattainment and interference with 
maintenance in New Jersey.
3. Meteorological Data
    Similar to the NJDEP AERMOD application, the EPA AERMOD modeling 
was based on 1 year of site-specific meteorological data collected from 
a 100-meter instrumented tower and SODAR located about 2.2 kilometers 
west of the Portland Plant, for the period July 1993 through June 1994. 
This is the same meteorological database used in the NJDEP AERMOD 
analysis.
    As noted earlier, there is a difference of about 100 meters between 
the base elevation for the meteorological tower and the Portland Plant 
stack base elevation. This raises concerns regarding how the 
meteorological data should be input to the AERMOD model, especially 
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 300 to 400 
meters above stack base. Given that the vertical variability of wind 
directions in the Portland Plant area documented in Exhibit 11 
submitted with NJDEP's May 13, 2010, petition, a key component of the 
modeling analysis is the representativeness of the site-specific winds 
for transport and dispersion of the Portland Plant emissions. 
Therefore, to address the issues of representativeness for this 
application, EPA made several adjustments to the meteorological data 
for the EPA remedy modeling, compared to the data used by NJDEP.
    Specifically, we made some adjustments to the measurement heights 
for the Portland Plant site-specific meteorological data. Given that 
the local terrain relief is about 100 meters, and assuming that local 
terrain effects on flow would extend up to about 3 times the height of 
the ``obstacles'', we conclude that we should apply a simple adjustment 
based on the 100-meter difference in base elevations to measurement 
heights at or above 300 meters. It is reasonable to assume that little 
or no adjustment should be applied to the lowest level winds due to the 
dominance of surface drag and other local influences. In addition to 
the height adjustment, several other changes were made to the 
meteorological data inputs (see the Modeling TSD for additional 
details).
4. Receptor/Terrain Data
    As noted in section V, EPA examined the terrain and receptor 
processing from the NJDEP AERMOD analysis and concluded that NJDEP's 
processing of terrain data based on several 7.5-minute (30-meter) DEM 
terrain files and two 1-degree (90-meter) DEM files for use in AERMOD 
was appropriate. However, EPA's AERMOD modeling was based on the 
application of the AERMAP terrain processor using the National 
Elevation Dataset (NED) format (USGS, 2002), which reflects updates to 
the older DEM terrain data. Additional details can be found in the 
Modeling TSD.
5. Portland Plant Emissions and Source Characteristics
    The EPA AERMOD analysis used allowable SO2 emissions 
rates for Portland Plant units 1, 2, and 5 along with stack parameters 
shown in Table VII.A-1 \25\:
---------------------------------------------------------------------------

    \25\ The allowable emissions and stack parameters in Table 
VII.A-1 for units 1 and 2 are the same as used by NJDEP. The 
allowable emissions and stack parameters for unit 5 are based on a 
2010 report regarding the Portland Plant prepared for RRI Energy.

                                                  Table VII.A-1
----------------------------------------------------------------------------------------------------------------
                                     Permitted                                         Stack
             Source                emission rate   Stack height   Stack diameter    temperature   Stack velocity
                                       (g/s)            (m)             (m)             (K)            (m/s)
----------------------------------------------------------------------------------------------------------------
Portland Plant Coal Unit 1......           733.3          121.92            2.84           403.0            43.3

[[Page 19674]]

 
Portland Plant Coal Unit 2......         1,121.0          121.72            3.79           406.0            36.2
Portland Plant Turbine 5........            12.0           42.7             6.1            821.5            36.6
----------------------------------------------------------------------------------------------------------------

6. Identification of Background Concentration To Use in the Remedy 
Analysis
    The dispersion modeling submitted by NJDEP with the September 17, 
2010, petition only included emissions from units 1 and 2 at the 
Portland Plant, and did not account for background concentrations of 
SO2 from other sources. NJDEP did not offer any rationale 
regarding the exclusion of any contribution from background 
concentrations in the modeling.\26\ Therefore, we address it here.
---------------------------------------------------------------------------

    \26\ Arguably, since the NJDEP modeling showed modeled 
violations of the NAAQS without background concentrations, it was 
not necessary for them to identify and/or add background 
concentrations to the results. However, in order to develop a 
remedy, it is necessary to consider background concentrations.
---------------------------------------------------------------------------

    Section 8.2 of Appendix W provides guidance regarding the inclusion 
of background concentrations in dispersion modeling demonstrations of 
compliance with the NAAQS under PSD regulations. Appendix W defines 
``background air quality'' as including ``pollutant concentrations due 
to: (1) Natural sources; (2) nearby sources other than the one(s) 
currently under consideration; and (3) unidentified sources.'' See 
Section 8.2.1a. EPA recently issued additional clarification regarding 
application of Appendix W guidance for the 1-hour NO2 
NAAQS,\27\ indicating that portions of that guidance are equally 
applicable to the 1-hour SO2 NAAQS. Two topics addressed in 
the March 1, 2011, guidance that are relevant here are the 
determination of background concentrations and combining modeled 
results with monitored background concentrations to determine 
cumulative impacts. While the guidance does not explicitly address 
dispersion modeling analyses in the context of a section 126 petition, 
we believe that the guidance provides an appropriate basis for the 
modeling conducted for the Portland Plant in support of this action.
---------------------------------------------------------------------------

    \27\ ``Additional Clarification Regarding Application of 
Appendix W Modeling Guidance for the 1-hour NO2 National 
Ambient Air Quality Standard.'' Memorandum from Tyler Fox, OAQPS/
AQAD, dated March 1, 2011.
---------------------------------------------------------------------------

    A review of SO2 emission sources within 50 km of the 
Portland Plant identified 10 sources, located mostly in Pennsylvania 
southwest of the Portland Plant. One of the closest sources is the PPL 
Martins Creek Plant located about 14 km south-southwest of the Portland 
Plant. Martins Creek emitted around 1,000 tons per year of 
SO2 in 2009. The next closest sources with SO2 
emissions of at least 2,000 tpy are two cement plants located in the 
Lehigh Valley about 25-30 km southwest of the Portland Plant. A more 
detailed discussion of nearby sources is provided in the Modeling TSD.
    Of the SO2 emission sources identified for possible 
inclusion in the modeling analysis, the Martins Creek Plant is the only 
source that is large enough and close enough to the Portland Plant to 
be considered for inclusion in the modeling analysis. However, the 
SO2 emissions from the Martins Creek Plant are somewhat 
intermittent (as noted earlier, Martins Creek units 3 and 4 averaged 
about 1,039 and 584 hours of operation per year respectively). Even 
more fundamentally, the purpose of this modeling is to determine the 
impact of the Portland Plant itself on the downwind nonattainment 
areas. Any intermittent impacts from Martins Creek would be in addition 
to the impacts from the Portland Plant and the Portland Plant would 
have no obligation to remedy any violations associated solely with 
those emissions. This modeling uses actual monitored background levels 
of SO2 such that it is reasonable to expect that the 
contribution of intermittent emissions from Martins Creek and other 
nearby sources is accounted for in EPA's analysis. This approach is 
also consistent with the modeling analysis conducted by NJDEP. Further 
details regarding our assessment of nearby SO2 sources are 
provided in the Modeling TSD.
    There are currently three operating SO2 monitors within 
50 km of the Portland Plant, including the Chester monitor located 
about 36 km southeast of the Portland Plant in Morris County, New 
Jersey, the Easton monitor located about 27 km southeast in Northampton 
County, Pennsylvania, and the Columbia Lake WMA monitor located about 2 
km northeast in Warren County, New Jersey. The Columbia monitor has 
only been in operation since September 23, 2010, while the Chester and 
Easton(2) monitors have been in operation for several years.
    Of the two long term SO2 monitors, the ambient 
SO2 data from the Chester, New Jersey, monitor provides the 
most representative background concentrations for this analysis since 
the distribution of sources impacting the Chester monitor is more 
similar to the distribution of sources around the Portland Plant. While 
the Easton(2), Pennsylvania, monitor is better situated to capture 
background concentrations upwind in relation to Portland Plant impacts 
in New Jersey, the Easton(2) monitor is close enough to the Lehigh 
Valley Cement Plants and other SO2 sources that monitored 
SO2 levels at Easton(2) would overestimate background 
concentrations applicable to this analysis.
    The Columbia monitor data period is too short to serve as a source 
of monitored background concentrations for this application. Given its 
proximity to the Portland Plant, it is likely to capture ambient 
SO2 impacts associated with the Portland Plant emissions 
under appropriate meteorological conditions. The location of the 
Columbia monitor also suggests that it may provide some useful insight 
into background concentration levels within the area by examining the 
concentration distribution during periods that are not affected by 
emissions from the Portland Plant.
    Based on an assessment of the available SO2 monitoring 
data, we determined that the Chester monitor is the most appropriate 
monitor to account for background SO2 concentrations for the 
Portland Plant. Consistent with the March 1, 2011, guidance, we 
included monitored concentrations based on the 99th-percentile by 
season and hour-of-day from the Chester data for 2007 through 2009 (the 
most recent data available) to account for background concentrations. 
These background SO2 concentrations by season and hour-of-
day varied from 13 [mu]g/m\3\ to 60 [mu]g/m\3\. Examination of hourly 
SO2 concentrations for both the Chester monitor and the 
available data from the Columbia monitor indicates very low 
concentrations (less than 3 ppb) during

[[Page 19675]]

the majority of the hours. However, we consider the background 
concentrations used in our analysis (13 [mu]g/m\3\ to 60 [mu]g/m\3\) to 
be appropriate for this application given that no other emission 
sources were explicitly modeled. A more detailed discussion of our 
assessment and use of monitored SO2 concentrations for this 
analysis are provided in the Modeling TSD.
7. Summary of EPA's Modeling Results
    The results of the AERMOD model runs relied on by EPA to determine 
the appropriate remedy are described later and fully documented in the 
Modeling TSD which is included in the docket.
    EPA's modeling based on the NJDEP coarse receptor grids resulted in 
a 1-hour SO2 modeled design value of 841 [mu]g/m\3\ (about 
321 ppb) at a receptor located about 3 kilometers north-northeast of 
the Portland Plant. Compared to the initial coarse grid analysis 
conducted by NJDEP, EPA's modeled design value is about 32 percent 
lower (compared to 1,236 [mu]g/m\3\) and occurs at a different location 
within the modeling domain. While EPA's modeling showed peak impacts 
much lower than NJDEP's peak design value, we note that EPA's modeled 
peak design value of 841 [mu]g/m\3\ is about 90 percent higher than 
NJDEP's modeled impact at EPA's peak receptor location. These 
differences are likely due to the adjustments in the processing of 
meteorological data input to the model. The adjustments to the 
measurement heights could result in significant differences in the 
transport direction for particular hours, as well as somewhat lower 
wind speeds. Both of these factors could shift the modeled impact area 
away from the higher terrain around the Delaware Water Gap toward a 
different part of the domain. The inclusion of observed 
[sigma]w data (standard deviation of the vertical velocity 
fluctuations) from the SODAR in the EPA modeling could also account for 
this shift in the maximum impact area from the Portland Plant. If 
observed [sigma]w values are higher than the reference 
values used in AERMOD in the absence of observations, then modeled 
impacts near the Delaware Water Gap, which are associated with direct 
plume impaction on the complex terrain, could be significantly lower. 
In contrast, larger [sigma]w values would tend to increase 
concentrations in the lower terrain, northeast of the Portland Plant, 
by mixing the plume to the ground faster. This would result in maximum 
impacts closer to the source.
    Based on the results from the initial coarse grid analysis, EPA 
developed a finer resolution receptor network that included two 
separate grids with 100-meter horizontal resolution. The smaller of the 
two fine resolution grids covers the impact area near the Delaware 
Water Gap to the northwest, and is similar to NJDEP's 100-meter fine 
grid, but is extended an additional 500 meters to the north and east. 
The larger fine resolution grid is focused on the area surrounding the 
maximum design value from the EPA's initial coarse grid model run, and 
extends about 5 km north, 4 km east, 1 km south and 2 km west of the 
Portland Plant.
    EPA's modeling based on the 100-meter fine receptor grids resulted 
in modeled design value (including background) of 851.1 [mu]g/m\3\ 
(about 325 ppb). The total concentration of 851.1 [mu]g/m\3\ consists 
of the contribution from the Portland Plant of 811.8 [mu]g/m\3\ plus 
39.3 [mu]g/m\3\ from background. This result is slightly higher than 
(and near the location of) the controlling coarse grid result.
a. Calculation of Emissions Limits Based on Maximum Modeled Impacts 
From Units 1 and 2 Plus Background
    As detailed previously, the modeled maximum 99th percentile (4th-
highest) daily maximum 1-hour SO2 concentration (including 
monitored background) from the Portland Plant in New Jersey was 851.1 
[mu]g/m\3\. Table VII.A-2 shows the contribution from each of the 
Portland Plant units to the design value concentration.

                                                  Table VII.A-2
----------------------------------------------------------------------------------------------------------------
             Unit 1                     Unit 2              Unit 5            Background             Total
----------------------------------------------------------------------------------------------------------------
371.7 [mu]g/m\3\................  439.2 [mu]g/m\3\..  0.91 [mu]g/m\3\...  39.3 [mu]g/m\3\...  851.1 [mu]g/m\3\.
----------------------------------------------------------------------------------------------------------------

    Based on this result, EPA calculated the emissions reduction needed 
to eliminate the Portland Plant's significant contribution to 
nonattainment in New Jersey. The calculation is relatively simple in 
this case because emissions from the Portland Plant alone cause 
violations of the 1-hour SO2 NAAQS in New Jersey and 
background levels of SO2 are very low. If the modeled 
concentration from the Portland Plant plus background is reduced to a 
level that is below the 1-hour SO2 NAAQS, then there will be 
no modeled violations of the NAAQS in New Jersey.
    Based on the EPA modeling results, an 81 percent reduction in 
allowable SO2 emissions from Portland Plant units 1 and 2 is 
needed to reduce the Portland Plant contribution plus background to 
below the NAAQS. The calculation is as follows: (Total modeled 
concentration)--(NAAQS--background)/(total modeled concentration). This 
calculation recognizes that the assumed background concentration cannot 
be reduced. The actual calculation based on Table VII.A-2 is (811.8)-
(196-39.3)/811.8. This results in a reduction of 80.7 percent, which we 
round to 81 percent.
    In this calculation, the contribution from all modeled sources 
(units 1, 2, and 5) is included in the total contribution. However, the 
contribution from unit 5 is only 0.1 percent of the total contribution 
(0.91 [mu]g/m\3\ contribution to the design value). 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 therefore can be added to the irreducible 
background value. This alternative calculation gives an emissions 
reduction of 80.8 percent (which is essentially the same as the 
previous 80.7 percent calculation). Therefore, we conclude that only 
emissions reductions from units 1 and 2 are needed in order to ensure 
that the downwind area in New Jersey will be able to attain the NAAQS 
and will not have maintenance problems and that a revised emissions 
limit is not needed for unit 5.
    While a total emissions reduction of 81 percent for both units 1 
and 2 eliminates all modeled violations in New Jersey, an additional 
question remains. Can the emissions limit be met by over controlling 
one unit (by more than 81 percent) and under controlling the other unit 
(by less than 81 percent)? Based on our analysis, there are many 
different combinations of emissions limits for units 1 and 2 that would 
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 at

[[Page 19676]]

different times. Therefore, the emissions limit has to be assigned to 
each individual unit and cannot be a combined limit. There are many 
different combinations of emissions limits for units 1 and 2 that would 
eliminate violations of the SO2 NAAQS in New Jersey, but we 
are not able to examine an unlimited number of combinations. Therefore 
we are proposing an emissions limit based on an 81 percent reduction in 
allowable emissions at both units 1 and 2. This leads to a proposed 
SO2 emissions limit for unit 1 of 1105 lbs/hr (5820*0.19) 
and a proposed SO2 emissions limit for unit 2 of 1691 lbs/hr 
(8900*0.19).
    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 proposed emissions levels, 
all receptors in New Jersey were below the 1-hour SO2 NAAQS. 
The modeled 99th percentile (4th-highest) daily maximum 1-hour 
SO2 concentration was 192.2 [mu]g/m\3\ (including a 
background concentration of 41.9 [mu]g/m\3\).
    EPA is requesting comment on other possible combinations or 
approaches in setting limits that are no less stringent than the 
proposed limits, but also result in elimination of the modeled 
violations while allowing for operating flexibility and load shifting. 
For example, a combined limit could be set for both units 1 and 2, in 
conjunction with individual limits, such as those proposed, for units 1 
and 2. Similarly, a limit could be set for emissions from all relevant 
units at the plant accompanied by individual limits for units 1 and 2. 
EPA also requests comment on the proposed emissions limit calculations.

VIII. Proposed Emission Limits and Compliance Schedules

A. Statutory Requirements for Sources for Which EPA Makes a Section 
126(b) Finding

    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 three 
month period ``if such source complies with such emission limitations 
and compliance schedules (containing 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 
three years after the date of such finding.'' 72 U.S.C. 7426(c). Thus, 
unless the Administrator affirmatively decides to permit continued 
operation of the source and establishes emission limitations and 
compliance schedules, an existing major source subject to a section 126 
finding must shut down in three months. However, if the source complies 
with the emission limitations and compliance schedules established by 
the Administrator, it may continue operation.
    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 
compliance option to be implemented. Furthermore, EPA recognizes that 
in some instances a source may choose to cease operation as its method 
of compliance. EPA is therefore requesting comment on the meaning of as 
``expeditious as practicable'' in this context.
    EPA recognizes both that the statute requires that any compliance 
schedule ensure compliance as ``expeditiously as practicable'' and also 
that while the statute directs EPA to establish emission limits and 
compliance schedules, it does not foreclose EPA from allowing the 
source to select a compliance option. EPA thus seeks to balance the 
statutory requirement of compliance as ``expeditiously as practicable'' 
with the goal of ensuring that the regulation does not unnecessarily 
limit the options available to the source to achieve compliance within 
the statutorily mandated timeframe. For these reasons, EPA has 
determined that it would be reasonable to interpret the statute as 
allowing EPA to develop different compliance schedules for different 
compliance options. By doing so, EPA can both give flexibility to the 
source to select an appropriate compliance option and ensure that 
compliance is achieved as ``expeditiously as practicable.'' As 
discussed later, EPA is also explicitly requesting comment on how to 
interpret the term ``as expeditiously as practicable'' when the method 
of compliance selected is to cease operations.

B. Proposed Emission Limits

    As explained in this subsection, EPA is proposing specific emission 
limitations and a specific compliance schedule that would apply unless 
the Portland Plant decides to cease operation as its method of 
compliance. EPA requests comment on all aspects of the emission limits 
and compliance schedule discussed later.
    Based on the NJDEP AERMOD dispersion modeling analysis and EPA's 
independent assessment, EPA proposes to allow the continued operation 
of the Portland Plant beyond the three months, provided that the 
Portland Plant complies with a SO2 emission limit of 1105 
lbs/hr for unit 1, and 1691 lbs/hr for unit 2, representing an 81 
percent reduction from currently allowable SO2 emissions for 
each unit, to eliminate its significant contribution to nonattainment 
and prevent it from interfering with maintenance of the 1-hour 
SO2 NAAQS in New Jersey. The source would be required to 
comply with this emission limit and the compliance deadlines and 
schedules (including increments of progress) set by EPA in the final 
rulemaking. EPA's proposed compliance schedules are discussed in more 
detail in sections C and D of this section.
    EPA believes that these proposed emission limits for units 1 and 2 
are appropriate since AERMOD modeling performed as described in section 
VII of this notice and in the TSD demonstrates that the Portland Plant 
must reduce its SO2 emissions to these levels in order to 
reduce the modeled SO2 concentration in New Jersey below the 
1-hour SO2 NAAQS level of 196 [mu]g/m\3\. As also discussed 
previously, EPA believes this is the appropriate remedy in this 
particular circumstance where the modeling shows that emissions from a 
single plant (the Portland Plant) are, by themselves, causing NAAQS 
exceedances downwind and background concentrations of the relevant 
pollutant are low. EPA requests comment on the emission limits proposed 
for units 1 and 2.
    EPA is not proposing to revise emission limits on the Portland 
Plant's smaller units (i.e., units 3, 4, 5, and the auxiliary boiler). 
Based on our review of their emissions, EPA proposes revised emission 
limits are not needed at units 3, 4, 5, and the auxiliary boiler. 
Portland Plant units 3, 4, 5, and the auxiliary boiler have very small 
emissions, in comparison to units 1 and 2. EPA's

[[Page 19677]]

modeling of unit 5 found a total contribution of only 0.1 percent 
(i.e., 0.91 [mu]g/m\3\ contribution to the design value) so that 
reductions in its contribution would provide a negligible reduction to 
the modeled design value and thus do not need to be reduced. Annual 
SO2 emissions reported in the 2008 NEI, Version 1 for the 
auxiliary boiler, unit 3 and unit 4 were 0.01, 0.02, and 0.03 tons, 
respectively. Therefore, given the negligible modeled contribution from 
unit 5, it can be assumed that emissions from these units do not need 
to be reduced. Therefore, units 3, 4, 5, and the auxiliary boiler can 
continue to operate at their previous emissions limit. EPA requests 
comment on its proposed determination not to establish emission limits 
for units 3, 4, 5, and the auxiliary boiler.

C. Proposed Compliance Schedules

    Section 126 allows the Administrator to permit the continued 
operation of a source if the source complies with emission limitations 
and compliance schedules (including increments of progress) to bring 
about compliance as expeditiously as practicable but in no case later 
than 3 years after the date of the finding. See 42 U.S.C. 7426(c). EPA 
proposes in this section the compliance schedule that would apply 
unless the source opts to cease operation of the units subject to 
emission limits. In subsection D later, EPA is requesting comment on an 
alternate compliance schedule that would apply if the source opts to 
cease operations at units subject to emission limits as its method of 
compliance. As part of that, we are asking for comment on what would 
constitute compliance ``as expeditiously as practicable'' if the source 
decides to cease operation of the units subject to emission limits as 
its method of compliance. The proposed compliance schedule and 
increments of progress discussed in this subsection were developed 
based on the assumption that the plant would need time to install 
controls to reduce its emissions. They would not apply if the 
compliance option selected is to cease operation of the units subject 
to emission limits.
    EPA proposes to require compliance with the emission limits 
described in subsection VIII.B no later than 3 years from the effective 
date of the section 126 finding. EPA is asking for comment on whether 3 
years from the effective date of the section 126 finding is ``as 
expeditious as practicable.'' In addition, EPA proposes a schedule of 
interim reduction steps that will provide incremental progress toward 
eventual compliance with the requirements of section 110(a)(2)(D)(i)(I) 
and 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.
    EPA is proposing to include an interim reduction requirement 
because section 126 calls for the establishment of a compliance 
schedule ``including increments of progress,'' 42 U.S.C. 7426, and 
interim reduction requirements constitute important increments of 
progress towards full compliance. More specifically, EPA is proposing 
to require the source to meet an SO2 emission limit of 2910 
lbs/hr for unit 1 and 4450 lbs/hr for unit 2, representing a 50 percent 
reduction from allowable SO2 emissions, after 1 year. EPA is 
proposing this interim reduction because, as explained previously in 
further detail, EPA's analysis supports that the Portland Plant's Units 
1 and 2 are significantly contributing to nonattainment or interfering 
with maintenance of the 1-hour SO2 NAAQS in New Jersey. EPA 
has evaluated the emission reduction options available and has 
determined that several potentially available options could provide 
incremental reductions such as reagent injection, switching to lower 
sulfur coal and load shifting. Information from the U.S. Department of 
Interior, U.S. Geological Survey indicates lower sulfur coal may be 
available in Pennsylvania.\28\ EPA's analysis of available control 
technologies for coal-fired electric generating units and experience 
with coal-fired electric generating units also support that reagent 
injection can achieve emissions reductions at coal-fired electric 
generating units in excess of fifty percent and can be installed and 
operational on coal-fired electric generating units in less than 12 
months.\29\ EPA requests comment on the proposed interim reduction 
requirements for units 1 and 2, including achievability of limits in 
the time proposed, and the impact of the reductions on the reliability 
of the electric grid.
---------------------------------------------------------------------------

    \28\ See information from the U.S. Department of the Interior, 
U.S. Geological Survey at http://pubs.usgs.gov/of/1998/of98-763/#fig2.
    \29\ See Summary Report, Trona Injection Tests, Mirant Potomac 
River Station, Unit 1, November 12- December 23, 2005 at http://www.oe.energy.gov/DocumentsandMedia/mirant_012006_g.pdf; Kong, 
Yougen and Davidson, Heidi, Dry Sorbent Injection of Sodium Sorbents 
for SO2, HCl, and Mercury Mitigation, May 11-13, 2010 at 
http://www.seas.columbia.edu/earth/wtert/sofos/nawtec/nawtec18/nawtec18-3560.pdf; ADA-ES, Inc, TOXECONTM Retrofit for 
Multi-Pollutant Control on Three 90-MW Coal-Fired Boilers, Topical 
Report: Performance and Economic Assessment of Trona-Based 
SO2/NOX Removal at the Presque Isle Power 
Plant Prepared for We Energies and DOE/NETL, August 25, 2008 at 
http://www.netl.doe.gov/technologies/coalpower/cctc/ccpi/pubs/SOx-Ox%20Reduction%20at%20PIPP%20- 20Topical%20Report%20Final.pdf; and 
ENSR Corporation, BART Analysis for the Kincaid Power Plant Prepared 
for Dominion Energy, Inc., January 2009 at http://www.epa.state.il.us/air/drafts/regional-haze/bart-kincaid.pdf.
---------------------------------------------------------------------------

    EPA also proposes to establish the following milestones that the 
source would be required to meet to demonstrate that it is on track to 
achieving full compliance as expeditiously as practicable and no later 
than the 3 year deadline.
    (1) Within 3 months of EPA's finding, the Portland Plant shall 
notify EPA whether it will continue to operate subject to the emission 
limitations and compliance schedules established by EPA herein, whether 
under the proposed emissions limits or under an alternative where the 
plant would cease operation, such as the alternative compliance option 
presented for comment later in this notice, in which the plant could 
chooses to cease operation by a date certain, and meet certain interim 
milestones for reducing emissions. If the plant plans to continue to 
operate subject to emissions limits, the plant shall also indicate how 
the plant intends to achieve full compliance with the emission limits 
established in this notice. Specifically, the plant 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. The Portland Plant must also include in this notice what 
physical or operational changes, if any, the plant will implement as 
its method of compliance with the emission limits and compliance 
schedules EPA will establish in the section 126 finding, including 
predicted emissions reductions and emission rates after changes are 
implemented. EPA requests comment on all aspects of this proposed 
requirement, including on what specific information should be included 
in this notification and the appropriate level of detail that should be 
required.
    (2) If the notice required by paragraph (1) above indicates that 
the plant intends to continue operation of the plant past the three 
month period, the plant must also comply with the requirements in 
paragraphs (3)-(7) later.
    (3) No later than 3 months from the date of the section 126 
finding, the Portland Plant shall submit to EPA a modeling protocol, 
consistent with EPA's Guideline on Air Quality Models, which is 
codified at 40 CFR Part 51, Appendix W and other relevant modeling 
guidance issued to support regulatory programs, for air modeling of the 
selected remedy. The air modeling to be conducted by the source will 
need

[[Page 19678]]

to demonstrate that, when that remedy is implemented, the Portland 
Plant will no longer significantly contribute to nonattainment or 
interfere with maintenance in New Jersey with respect to the 1-hour 
SO2 NAAQS. All units at the Portland Plant (i.e., units 1 
thru 5 plus the auxiliary boiler) shall be included in the modeling 
analysis, in order to demonstrate that emissions from the Portland 
Plant will not significantly contribute to nonattainment or interfere 
with maintenance with respect to the 1-hour SO2 NAAQS.
    (4) If EPA identifies deficiencies in the modeling protocol 
submitted by the source, the Portland Plant will have 15 business days 
to submit a revision to correct any deficiencies identified by EPA.
    (5) No later than 6 months from the date of the section 126 
finding, Portland Plant shall submit a modeling analysis for the 
selected remedy performed in accordance with the modeling protocol.
    (6) Beginning 6 months after the section 126 finding and continuing 
every 6 months until the final compliance date, the Portland Plant 
shall submit to EPA 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.
    (7) No later than 3 years following EPA's final rulemaking, the 
Portland Plant shall submit a final project report which demonstrates 
compliance with the emission limits in the final rulemaking. The final 
report shall include the date when full operation of controls was 
achieved at the Portland Plant after shakedown; as well as a minimum of 
1 month of CEMS data demonstrating compliance with the emission limits 
in the final rulemaking.
    EPA requests comment on all aspects of this proposed compliance 
schedule and the proposed increments of progress. Key issues EPA is 
requesting comment on include: Whether the compliance schedule is 
sufficient to achieve compliance as expeditiously as practicable; 
whether additional increments of progress are necessary and, if so, 
what they should be; what level of detail should be required in the 
notices the Portland Plant will be required to submit; whether the 
deadline for each increment of progress is appropriate or should be 
sooner or later; whether continued periodic progress reports should be 
required after the final compliance date; and whether the required 
progress reports and final project reports are sufficient to document 
and demonstrate compliance.

D. Alternate Compliance Schedule

    As noted previously, EPA is also requesting comment on how to 
interpret the phrase ``compliance as expeditiously as practicable'' 
when the source has selected to cease operation of either unit as its 
method of compliance with the emission limit for that unit and 
cessation cannot occur within 3 months of EPA's finding. If EPA 
determines that it is appropriate to do so, EPA will include in the 
final rule a compliance schedule and increments of progress that would 
apply only if the source opts to cease operations at either unit 
subject to an emission limit as its method of compliance with the 
limit. EPA, therefore, is also requesting comment on what an 
appropriate compliance schedule would be, what factors EPA should 
consider in setting the compliance schedule, and what form the 
increments of progress should take. Though not an exhaustive list of 
relevant factors, EPA is taking comment on the following factors for 
determining what ``compliance as expeditiously as practicable'' means 
when compliance with an emission limit is to be achieved by ceasing to 
operate the unit subject to the limit: Electricity grid reliability 
issues; contracts that the source has with the electric utility 
independent service operator (ISO); other contractual obligations that 
the source has that would be impacted by a shutdown; whether the source 
is designated as a reliability must-run unit for any purpose by the 
ISO; whether some amount of electricity generating capacity at the 
source could be shut down in a shorter time period without creating 
reliability issues for the grid; what types of actions are required to 
address grid reliability (if there are any such issues), such as 
transmission line upgrades; how long it would take to address 
reliability issues (if there are any such issues); and the continued 
impact of interstate transport of emissions from the source on air 
quality in the affected State. EPA is also taking comment on whether 
other factors should be considered, and requests that commenters 
identify any additional relevant factors. In light of the factors 
enumerated previously as well as any other relevant factors, EPA is 
requesting comment on what would be an appropriate compliance schedule, 
that is as expeditious as practicable but no later than 3 years after 
the date of such finding, if compliance with the requirements of 
section 110(a)(2)(D)(i) is to be achieved by ceasing operations of the 
unit subject to the limit and cessation of operations cannot occur 
within 3 months of EPA's finding.
    In addition to these factors, EPA also requests comment on what 
increments of progress should be established as part of the compliance 
schedule discussed previously. EPA specifically requests comment on the 
relevant milestones that should be included in a compliance schedule. 
At a minimum the interim milestones discussed in paragraphs (1) through 
(4) of section VIII.C would apply. That is, the Portland Plant would be 
required to notify EPA whether it will cease to operate within 3 months 
of EPA's finding or whether it will continue to operate subject to the 
emission limitations and compliance schedules established by EPA 
herein. The Portland Plant would also need to submit a protocol for and 
later submit air quality modeling sufficient to demonstrate that 
emissions from the plant, after implementation of the remedy, will no 
longer significantly contribute to nonattainment or interfere with 
maintenance of the 1-hour SO2 NAAQS in New Jersey. This 
requirement would be waived only if the source opted to cease operation 
of all emitting units at the Portland Plant.
    EPA also specifically requests comment as to whether to include 
interim emission reductions during the period of time that the plant 
continues to operate after such a finding until the eventual shutdown. 
And if so, EPA requests comment as to the appropriate level of emission 
reductions.

IX. Statutory and Executive Order Reviews

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

    This proposed action is not a ``significant regulatory action'' 
under the terms of Executive Order (EO) 12866 (58 FR 51735, October 4, 
1993) and 13563 (76 FR 3821, January 21, 2011) and is therefore not 
subject to review under EO 12866 or EO 13563.

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., 
because this proposed rule, if finalized, under section 126 of the CAA 
will not in-and-of itself create any new information collection burdens 
but simply establishes a SO2 emission limit at the Portland 
Plant. Burden is defined at 5 CFR 1320.3(b).

[[Page 19679]]

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 proposed rule on 
small entities, I certify that this action will not have a significant 
economic impact on a substantial number of small entities. The 
SO2 emission limits for the Portland Plant being proposed in 
this notice do not impose any new requirements on small entities.
    We continue to be interested in the potential impacts of the 
proposed rule on small entities and welcome comments on issues related 
to such impacts.

D. Unfunded Mandates Reform Act

    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 
costs necessary to comply with the emission limit proposed in this 
notice are not expected to exceed $100 million or more for State, 
local, and Tribal governments, in aggregate, or the private sector in 
any 1 year. 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 action 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 proposed rule primarily affects 
private industry, and does not impose significant economic costs on 
State or local governments. Thus, Executive Order 13132 does not apply 
to this action.
    In the spirit of Executive Order 13132, and consistent with EPA 
policy to promote communications between EPA and State and local 
governments, EPA specifically solicits comment on this proposed action 
from State and local officials.

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 will not have 
a substantial direct effect on Tribal governments, on the relationship 
between the Federal government and Indian Tribes, or the 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

    EPA interprets Executive Order 13045 (62 FR 19885, April 23, 1997) 
as applying to those regulatory actions that concern health or safety 
risks, such that the analysis required under section 5-501 of the Order 
has the potential to influence the regulation. This action is not 
subject to Executive Order 13045 because it proposes to improve a State 
action for the implementation of a previously promulgated health or 
safety based Federal standards. EPA believes that the proposed 
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 not a significant regulatory action 
under Executive Order 12866.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, 12(d) (15 U.S.C. 272 note) 
directs EPA to use voluntary consensus standards in its regulatory 
activities unless to do so would be inconsistent with applicable law or 
otherwise impractical. Voluntary consensus standards are technical 
standards (e.g., materials specifications, test methods, sampling 
procedures, and business practices) that are developed or adopted by 
voluntary consensus standards bodies. NTTAA directs EPA to provide 
Congress, through OMB, explanations when the Agency decides not to use 
available and applicable voluntary consensus standards.
    This proposed rulemaking does not involve technical standards. 
Therefore, EPA is not considering the use of any voluntary consensus 
standards.

J. 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 United States.
    EPA has determined that this proposed rule, if finalized, 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. This proposed rule limits emissions of 
SO2 from the Portland Plant located in Northampton County, 
Pennsylvania.

List of Subjects in 40 CFR Part 52

    Administrative practice and procedure, Air pollution control, 
Intergovernmental relations, Reporting and recordkeeping requirements, 
Sulfur dioxide.

    Dated: March 31, 2011.
Lisa P. Jackson,
Administrator.
    For the reasons set forth in the preamble part 52 of chapter I of 
title 40

[[Page 19680]]

of the Code of Federal regulations are proposed to be amended as 
follows:

PART 52--[AMENDED]

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

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

Subpart NN-- Pennsylvania

    2. Section 52.2039 is added to read as follows:

Sec.  52.2039  Interstate transport.

    EPA has made a finding pursuant to section 126 of the Clean Air Act 
that emissions of sulfur dioxide (SO2) from the Portland 
Generating Station in Northampton County, Upper Mount Bethel Township, 
Pennsylvania significantly contribute to nonattainment and interfere 
with maintenance of the 1-hour SO2 national ambient air 
quality standard (NAAQS) in New Jersey. The owners and operators of the 
Portland Generating Station shall either cease operations no later than 
90 days from the effective date of the section 126 finding or comply 
with the requirements in paragraphs (b) through (e) of this section.
    (a) No later than 90 days from the effective date of the section 
126 finding, the owners and operators of the Portland Generating 
Station shall notify EPA whether the owners and operators will operate 
the Portland Generating Station after the date 90 days after the 
effective date of the section 126 finding in compliance with the 
requirements in paragraphs (b) through (e) of this section. If the 
owners and operators will operate the Portland Generating Station after 
such date, such notice must also specify the methods to be used to 
ensure compliance with the emission limits in paragraphs (b) and (c) of 
this section.
    (b) The owners and operators of Portland Generating Station in 
Upper Mount Bethel Township, Northampton County, Pennsylvania, 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 pounds per hour (``lbs/hr'') for unit 1 (identified with 
source ID 031 in Title V Permit No. 48-0006) and
    (2) 1,691 lbs/hr for unit 2 (identified with source ID 032 in Title 
V Permit No. 48-0006).
    (c) The owners and operators of the Portland Generating Station in 
Upper Mount Bethel Township, Northampton County, Pennsylvania, 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 the following limits:
    (1) 2,910 lbs/hr for unit 1 (identified with source ID 031 in Title 
V Permit No. 48-0006); and
    (2) 4,450 lbs/hr for unit 2 (identified with source ID 032 in Title 
V Permit No. 48-0006);
    (3) Provided that the limits in paragraphs (c)(1) and (c)(2) of 
this section shall not apply if the notice required by paragraph (a) of 
this section indicates that the owners and operators of the Portland 
Generating Station have decided to completely and permanently cease 
operation of 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) as the method of compliance with the emission 
limits in paragraph (b) of this section.
    (d) The owners and operators of the Portland Generating Station 
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 the Portland Generating Station 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 90 days after the effective date of the section 
126 finding, submit to EPA a modeling protocol that is consistent with 
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 EPA of any 
deficiencies in the modeling protocol under paragraph (d)(1)(i) of this 
section, submit to EPA a revised modeling protocol to correct any 
deficiencies identified in such notice.
    (iii) No later than 180 days after the effective date of the 
section 126 finding, submit to EPA a modeling analysis, performed in 
accordance with the modeling protocol under paragraphs (d)(1)(i) and 
(d)(1)(ii) of this section, for the compliance methods identified in 
the notice required by paragraph (a) of this section.
    (2) Starting 180 days after the effective date of the section 126 
finding and continuing every six months until the date three years 
after the effective date of the section 126 finding, submit to EPA 
progress reports on the implementation of the methods of compliance 
identified in the notice required by paragraph (a) of this section, 
including status of design, technology selection, development of 
technical specifications, awarding of contracts, construction, 
shakedown, and compliance demonstration. These reports shall include:
    (i) An interim project report, submitted no later than one year 
after the effective date of the section 126 finding, that demonstrates 
compliance with the emission limits in paragraph (c) of this section.
    (ii) A final project report, submitted no later than 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 the date when full operation of controls was achieved 
at the Portland Generating Station after shakedown.
    (3) The requirements in paragraphs (d)(1) and (d)(2) of this 
section shall not apply if the notice required by paragraph (a) of this 
section indicates that the owners and operators of the Portland 
Generating Station have decided to completely and permanently cease 
operation of 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) as the method of compliance with the emission 
limits in paragraph (b) of this section.
    (e) If the notice required by paragraph (a) of this section 
indicates that the owners and operators of the Portland Generating 
Station have decided to completely and permanently cease operation of 
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) as the method of compliance with the emission limits in paragraph 
(b) of this section, the owners and operators shall meet the following 
requirements:
    (1) No later than 90 days after the effective date of the section 
126 finding, submit to EPA an analysis of the time required to 
completely and permanently cease operations at 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) as expeditiously as 
practicable.
    (2) Within 15 business days of receipt of notice from EPA of any 
deficiencies in the analysis under paragraph (e)(1) of this section, 
submit to EPA a revised analysis to correct any deficiencies identified 
by EPA.
    (3) Completely and permanently cease operation of unit 1 
(identified with source ID 031 in Title V Permit No. 48-0006) by the 
date that achieves, as determined by the Administrator,

[[Page 19681]]

expeditious as practicable cessation of operation.
    (4) Completely and permanently cease operation of unit 2 
(identified with source ID 032 in Title V Permit No. 48-0006) by the 
date that achieves, as determined by the Administrator, expeditious as 
practicable cessation of operation.

[FR Doc. 2011-8166 Filed 4-6-11; 8:45 am]
BILLING CODE 6560-50-P