Supplemental Notice of Proposed Rulemaking for Prevention of Significant Deterioration and Nonattainment New Source Review: Emission Increases for Electric Generating Units, 26202-26227 [E7-8263]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 72, Number 88 (Tuesday, May 8, 2007)]
[Proposed Rules]
[Pages 26202-26227]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-8263]



[[Page 26201]]

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Part II





Environmental Protection Agency





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40 CFR Parts 51 and 52



Supplemental Notice of Proposed Rulemaking for Prevention of 
Significant Deterioration and Nonattainment New Source Review: Emission 
Increases for Electric Generating Units; Proposed Rule

Federal Register / Vol. 72, No. 88 / Tuesday, May 8, 2007 / Proposed 
Rules

[[Page 26202]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 51 and 52

[Docket ID No. EPA-HQ-OAR-2005-0163; FRL-8307-7]
RIN-2060-AN28


Supplemental Notice of Proposed Rulemaking for Prevention of 
Significant Deterioration and Nonattainment New Source Review: Emission 
Increases for Electric Generating Units

AGENCY: Environmental Protection Agency (EPA).

ACTION: Supplemental Notice of Proposed Rulemaking.

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SUMMARY: This action is a supplemental notice of proposed rulemaking 
(SNPR) to EPA's October 20, 2005 notice of proposed rulemaking (NPR). 
In the October 2005 NPR, EPA (we) proposed to revise the emissions test 
for existing electric generating units (EGUs) that are subject to the 
regulations governing the Prevention of Significant Deterioration (PSD) 
and nonattainment major New Source Review (NSR) programs (collectively 
``NSR'') mandated by parts C and D of title I of the Clean Air Act 
(CAA). We proposed three alternatives for the emissions test: a maximum 
achievable hourly emissions test, a maximum achieved hourly emissions 
test, and an output-based hourly emissions test. This action recasts 
the proposed options so that the output-based test becomes an 
alternative method to implement the maximum achieved or maximum 
achievable hourly tests, rather than a separate option. This SNPR also 
proposes a new option in which the hourly emissions increase test is 
added to the existing requirements for computing a significant increase 
and a significant net emissions increase on an annual basis. It also 
includes proposed rule language and supplemental information for the 
October 2005 proposal, including an examination of the impacts on 
emissions and air quality.
    These proposed regulations interpret the emissions increase 
component of the modification test under CAA 111(a)(4), in the context 
of NSR, for existing EGUs. The proposed regulations would promote the 
safety, reliability, and efficiency of EGUs. We are seeking comment on 
all aspects of this proposed rule.

DATES: Comments. Comments must be received on or before July 9, 2007. 
Under the Paperwork Reduction Act, comments on the information 
collection provisions must be received by the Office of Management and 
Budget (OMB) on or before June 7, 2007.
    Public Hearing: If anyone contacts us requesting to speak at a 
public hearing on or before May 29, 2007, we will hold a public hearing 
approximately 30 days after publication in the Federal Register.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2005-0163 by one of the following methods:
     https://www.regulations.gov: Follow the on-line 
instructions for submitting comments.
     E-mail: a-and-r-docket@epa.gov.
     Mail: Attention Docket ID No. EPA-HQ-OAR-2005-0163, U.S. 
Environmental Protection Agency, EPA West (Air Docket), 1200 
Pennsylvania Avenue, NW., Mail code: 6102T, Washington, DC 20460. 
Please include a total of 2 copies. In addition, please mail a copy of 
your comments on the information collection provisions to the Office of 
Information and Regulatory Affairs, Office of Management and Budget 
(OMB), Attn: Desk Officer for EPA, 725 17th Street, NW., Washington, DC 
20503.
     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-2005-0163. 
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-
2005-0163. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
https://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 https://www.regulations.gov or e-
mail. The https://www.regulations.gov website 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 https://
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, any form of encryption, and be free of any defects or 
viruses. For additional instructions on submitting comments, go to 
section B. of the SUPPLEMENTARY INFORMATION section of this document.
    Docket. All documents in the docket are listed in the https://
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, i.e., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, is not placed on the Internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available either electronically in https://
www.regulations.gov or in hard copy at the U.S. Environmental 
Protection Agency, Air Docket, 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: Ms. Janet McDonald, Air Quality Policy 
Division (C504-03), U.S. Environmental Protection Agency, Research 
Triangle Park, NC 27711, telephone number: (919) 541-1450; fax number: 
(919) 541-5509, or electronic mail e-mail address: 
mcdonald.janet@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

    Entities potentially affected by the subject rule for this action 
are fossil-fuel fired boilers and turbines serving an electric 
generator with nameplate capacity greater than 25 megawatts (MW) 
producing electricity for sale. Entities potentially affected by the 
subject rule for this action also include State, local, and tribal 
governments. Categories and entities potentially affected by this 
action are expected to include:

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------------------------------------------------------------------------
         Industry Group             SIC\a\             NAICS\b\
------------------------------------------------------------------------
Electric Services...............        491  221112.
Federal government..............   \1\22112  Fossil-fuel fired electric
                                              utility steam generating
                                              units owned by the Federal
                                              government.
State/local/Tribal government...      22112  Fossil-fuel fired electric
                                              utility steam generating
                                              units owned by
                                              municipalities. Fossil-
                                              fuel fired electric
                                              utility steam generating
                                              units in Indian country.
------------------------------------------------------------------------
\a\ Standard Industrial Classification
\b\ North American Industry Classification System.

B. Where can I get a copy of this document and other related 
information?
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    \1\ Establishments owned and operated by Federal, State, or 
local government are classified according to the activity in which 
they are engaged.
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    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 notice will be 
posted in the regulations and standards section of our NSR home page 
located at https://www.epa.gov/nsr.

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

    1. Submitting CBI. Do not submit this information to EPA through 
https://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 Park, 
NC 27711, Attention Docket ID No. EPA-HQ-OAR-2005-0163.
    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.

D. How can I find information about a possible public hearing?

    People interested in presenting oral testimony or inquiring if a 
hearing is to be held should contact Ms. Pamela S. Long, New Source 
Review Group, Air Quality Policy Division (C504-03), U.S. EPA, Research 
Triangle Park, NC 27711, telephone number (919) 541-0641. If a hearing 
is to be held, persons interested in presenting oral testimony should 
notify Ms. Long at least 2 days in advance of the public hearing. 
Persons interested in attending the public hearing should also contact 
Ms. Long to verify the time, date, and location of the hearing. The 
public hearing will provide interested parties the opportunity to 
present data, views, or arguments concerning these proposed rules.

E. How is the preamble organized?

    The information presented in this preamble is organized as follows:

I. General Information
    A. Does this action apply to me?
    B. Where can I get a copy of this document and other related 
information?
    C. What should I consider as I prepare my comments for EPA?
    D. How can I find information about a possible public hearing?
    E. How is the preamble organized?
II. Overview
    A. Option 1: Hourly Emissions Increase Test Followed by Annual
    Emissions Test
    B. Option 2: Hourly Emissions Increase Test
III. Analyses Supporting Proposed Options
    A. The Integrated Planning Model
    B. NSR Availability Scenarios--Description of the Scenarios
    C. NSR Availability Scenarios-Discussion of SO2 and 
NOX Results
    D. NSR Availability Scenarios-Discussion of PM2.5, 
VOC, and CO Results
    E. NSR Efficiency Scenario
IV. Proposed Regulations for Option 1: Hourly Emissions Increase 
Test Followed by Annual Emissions Test
    A. Test for EGUs Based on Maximum Achieved Emissions Rates
    B. Test for EGUs Based on Maximum Achievable Emissions
V. Proposed Regulations for Option 2: Hourly Emissions Increase Test
VI. Legal Basis and Policy Rationale
VII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and 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 Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations 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
VIII. Statutory Authority

II. Overview

    This action is a SNPR to EPA's October 20, 2005 (70 FR 61081) NPR. 
In the October 2005 NPR, we proposed to revise the emissions test for 
existing EGUs that are subject to the regulations governing the PSD and 
nonattainment major NSR programs (collectively ``NSR'') mandated by 
parts C and D of title I of the CAA. We proposed three alternatives for 
the emissions test: a maximum achievable hourly emissions test, a 
maximum achieved hourly emissions test, and an output-based hourly 
emissions test. In the NPR, we did not propose to include, along with 
any of the revised NSR emissions tests, any provisions for computing a 
significant increase or a significant net

[[Page 26204]]

emissions increase, although we solicited comment on retaining such 
provisions. In addition, we solicited comment on whether, if we revised 
the NSR test to be a maximum achieved emissions test or output-based 
emissions test, we should revise the NSPS regulations to include a 
maximum achieved emissions test or an output-based emissions test. This 
action recasts the proposed options so that the output test, instead of 
being an alternative to the maximum hourly achieved or maximum hourly 
achievable tests, becomes an alternative method for sources to 
implement those two tests. Specifically, we propose that each of the 
two tests would be implemented through (i) an input method (as defined 
below), (ii) the output method, or (iii) at the source's choice, either 
the input or output method. This action includes proposed rule language 
and supplemental information for the October 2005 proposal as it 
relates to the major NSR regulations, including an examination of the 
impacts on emissions and air quality that would result were we to 
finalize one of the applicability tests proposed in the October 2005 
proposal or in this SNPR, as described below.
    This action also proposes an additional option that was not 
included in the October 2005 rule. For convenience, this action 
characterizes the tests contained in the October 2005 NPR, described 
above, as Option 2 (with the maximum hourly achieved test characterized 
as Alternatives 1-4 and the maximum hourly achievable test 
characterized as Alternatives 5-6 within that Option 2, and with each 
of those tests including output-based alternatives). For the additional 
option proposed, which we characterize as Option 1, we are proposing 
that an hourly emissions increase test (either maximum achieved or 
maximum achievable, each with output-based alternatives) would include 
the significant net emissions increase test in the current major NSR 
rules, which is calculated on an actual-to-projected-actual annual 
emissions basis. We are also clarifying that Option 1 is our preferred 
option.
    When we proposed a revised emissions test for EGUs in October 2005, 
we referenced United States v. Duke Energy Corp., 411 F.3d 539 (4th 
Cir.) rehearing den.---- F.3d---- (2005), cert. granted ---- U.S.---- 
(2006). At the time of our proposal, the Fourth Circuit had denied the 
United States' petition for rehearing on the decision in Duke Energy, 
but the deadline for filing a petition for certiorari to the United 
States Supreme Court had not yet passed. Subsequently, on December 28, 
2005, Intervenor plaintiffs Environmental Defense Fund, North Carolina 
Sierra Club, and North Carolina Public Interest Research Group filed a 
petition for certiorari asking the court to address several matters. On 
May 15, 2006 the United States Supreme Court granted the petition for a 
writ of certiorari. On April 2, 2007, the Supreme Court vacated and 
remanded the Fourth Circuit decision. [549 U.S.---- (2007)] , 75 
U.S.L.W. 4167 (April 2, 2007).
    When we published the proposal in October 2005, it was in part in 
response to the Fourth Circuit's holding that EPA must read the 1980 
PSD regulations to contain an hourly test, consistent with the NSPS 
regulations. The Supreme Court's vacatur was based on its finding that 
such a reading of the 1980 PSD regulations ``was inconsistent with 
their terms.'' The Supreme Court, however, indicated that EPA may be 
able to revise the regulations when, as here, it has a rational reason 
for doing so. While there is no longer a need to provide national 
consistency in light of the Fourth Circuit decision, we believe that 
the options for a maximum hourly test that we proposed in our October 
2005 NPR and continue to propose in this SNPR are an appropriate 
exercise of our discretion, especially in light of the substantial EGU 
emission reductions from more efficient air quality programs 
promulgated after 1980. Accordingly, we continue to pursue the 
viability of imposing an hourly emissions test on EGUs for purposes of 
major NSR applicability.
    In May 2001, President Bush's National Energy Policy Development 
Group issued findings and key recommendations for a National Energy 
Policy. This document included numerous recommendations for action, 
including a recommendation that the EPA Administrator, in consultation 
with the Secretary of Energy and other relevant agencies, review NSR 
regulations, including administrative interpretation and 
implementation. The recommendation requested that we issue a report to 
the President on the impact of the regulations on investment in new 
utility and refinery generation capacity, energy efficiency, and 
environmental protection. Our report to the President and our 
recommendations in response to the National Energy Policy were issued 
on June 13, 2002. A copy of this information is available at https://
www.epa.gov/nsr/publications.html.
    In that report we concluded:

    As applied to existing power plants and refineries, EPA 
concludes that the NSR program has impeded or resulted in the 
cancellation of projects which would maintain and improve 
reliability, efficiency and safety of existing energy capacity. Such 
discouragement results in lost capacity, as well as lost 
opportunities to improve energy efficiency and reduce air pollution. 
(New Source Review Report to the President at pg. 3.)

On December 31, 2002, we promulgated final regulations that implemented 
several of the recommendations in the New Source Review Report to the 
President. However, that action left the NSR regulations as they 
related to utilities largely unchanged. This action continues to 
address the recommendations in the New Source Review Report to the 
President as they relate to electric utilities specifically and in 
light of the regulatory requirements for EGUs that have been 
promulgated since our 2002 regulations.
    The regulations proposed in the October 2005 NPR and on this action 
would promote the safety, reliability, and efficiency of EGUs. The 
proposed regulations are consistent with the primary purpose of the 
major NSR program, which is to balance the need for environmental 
protection and economic growth. The proposed regulations reasonably 
balance the economic need of sources to use existing physical and 
operating capacity with the environmental benefit of regulating those 
emissions increases related to a physical or operational change. This 
is particularly true in light of the substantial national EGU emissions 
reductions that other programs have achieved or are expected to 
achieve, which we described in detail at 70 FR 61083. Moreover, as the 
analyses included in this SNPR demonstrate, the proposed regulations 
would not have an undue adverse impact on local air quality.
    This section gives an overview of our proposed actions for major 
NSR applicability at existing EGUs, including the proposals in the NPR, 
as recast in this proposal, for the maximum hourly emissions tests and 
this additional proposal. Each of the options would promote the safety, 
reliability, and efficiency of EGUs. Each of the options would also 
balance the economic need of sources to use existing physical and 
operating capacity with the environmental benefit of regulating those 
emissions increases related to a change, considering the substantial 
national emissions reductions other programs have achieved or will 
achieve

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from EGUs. Our preferred Option is Option 1. We will select the final 
option after weighing the public comments on the Options. Table 1 
summarizes our two Options.
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    \2\ For clarity, this table lists all of the steps in the 
applicability determinations under the various options and 
alternatives. These steps include, as Step 1, the determination of 
whether a physical change or change in the method of operation has 
occurred. This Step 1 is included in the table solely for purposes 
of clarity; neither the October 2005 NPR nor this action proposes 
any action of any type (or makes any re-proposal) concerning the 
regulations defining physical change or change in the method of 
operation. Similarly, the steps also include, as Steps 3 and 4, the 
current net significance test; and this SNPR does not propose any 
action of any type (or make any re-proposal) concerning the current 
net significance test. Finally, this action does not propose any 
action of any type (or make any re-proposal) concerning the current 
applicability test for EGUs.

 Table 1.--Proposed Options for Major NSR Applicability for Existing EGU
                                   \2\
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Option 1..........................  Step 1: Physical Change or Change in
                                     the Method of Operation.
                                    Step 2: Hourly Emissions Increase
                                     Test.
                                     Alternative 1--Maximum
                                     achieved hourly emissions;
                                     statistical approach; input basis.
                                     Alternative 2--Maximum
                                     achieved hourly emissions;
                                     statistical approach; output basis.
                                     Alternative 3--Maximum
                                     achieved hourly emissions; one-in-5-
                                     year baseline; input basis.
                                     Alternative 4--Maximum
                                     achieved hourly emissions; one-in-5-
                                     year baseline; output basis.
                                     Alternative 5--NSPS test--
                                     maximum achievable hourly
                                     emissions; input basis.
                                     Alternative 6--NSPS test-
                                     maximum achievable hourly
                                     emissions; output basis.
                                    Step 3: Significant Emissions
                                     Increase Determined Using the
                                     Actual-to-Projected-Actual
                                     Emissions Test as in the Current
                                     Rules.\3\
                                    Step 4: Significant Net Emissions
                                     Increase as in the Current Rules.
Option 2..........................  Step 1: Physical Change or Change in
                                     the Method of Operation.
                                    Step 2: Hourly Emissions Increase
                                     Test.
                                     Alternative 1--Maximum
                                     achieved hourly emissions;
                                     statistical approach; input basis.
                                     Alternative 2--Maximum
                                     achieved hourly emissions;
                                     statistical approach; output basis.
                                     Alternative 3--Maximum
                                     achieved hourly emissions; one-in-5-
                                     year baseline; input basis.
                                     Alternative 4--Maximum
                                     achieved hourly emissions; one-in-5-
                                     year baseline; output basis.
                                     Alternative 5--NSPS test--
                                     maximum achievable hourly
                                     emissions; input basis.
                                     Alternative 6--NSPS test-
                                     maximum achievable hourly
                                     emissions; output basis.
------------------------------------------------------------------------

    We request public comment on all aspects of this action. We intend 
to finalize either Option 1 or Option 2. We will also finalize either 
the maximum achieved or the maximum achievable alternative. We intend 
to respond to public comments on the October 20, 2005 NPR and this 
notice in a single Federal Register Notice and Response to Comments 
Document at the time that we take final action.
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    \3\ Steps 3 and 4 only apply when a unit fails Step 2. (That is, 
it is determined that an hourly emissions increase would occur.)
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A. Option 1: Hourly Emissions Increase Test Followed by Annual 
Emissions Test

    In the NPR, we did not propose to include, along with any of the 
revised NSR emissions tests, any provisions for computing a significant 
emissions increase or a significant net emissions increase, although we 
solicited comment on retaining such provisions. Many commenters 
believed netting is required under the Alabama Power Court decision, 
and supported options retaining netting. Therefore, we are proposing 
that major NSR applicability would include an hourly emissions increase 
test, followed by the current regulatory requirements for the actual-
to-projected-actual emissions increase test to determine significance, 
and the significant net emissions increase test. We call this approach 
Option 1 and we are proposing it as our preferred option. Specifically, 
under Option 1, the major NSR program would include a four-step process 
as follows: (1) Physical change or change in the method of operation; 
(2) hourly emissions increase test ; (3) significant emissions increase 
as in the current major NSR regulations; and (4) significant net 
emissions increase as in the current major NSR regulations. Section IV 
of this preamble describes Option 1 in more detail. Our proposed 
regulatory language is for Option 1.
    Option 1 facilitates improvements for efficiency, safety, and 
reliability, without adverse air quality effects (as the discussion of 
the IPM and air quality analyses in Section III indicates). 
Specifically, changes that will not increase the hourly emissions 
rate--such as those to make repairs to reduce the number of forced 
outages--do not require further review under Option 1. That is, if 
there would be no hourly emissions increase following a physical change 
or change in the method of operation, the proposed rule does not 
require a determination of whether a significant increase or a 
significant net emissions increase would occur. Thus, Option 1 would 
simplify major NSR for changes where there is no increase in hourly 
emissions. However, many public commenters urged that we retain the 
significant emissions increase component of the emissions increase 
test. Therefore, we are proposing further review under Option 1 in 
instances where a physical or operational change at a given unit would 
increase the hourly emissions rate, such as would occur where there is 
an increase in existing capacity. In such cases, Option 1 requires 
further review using the significant increase and significant net 
emissions increase components of the current regulations. This approach 
retains an annual emissions test in determining NSR applicability.
    We are proposing both a maximum achieved hourly and a maximum 
achievable hourly emissions increase test under Step 2 of Option 1, 
which we discuss in detail in Section IV.A. of this preamble. 
Consistent with our policy goal of improving energy efficiency, we are 
proposing both an input \4\ and output based format for both the 
maximum achievable and maximum achieved hourly emissions increase test 
options. Specifically, we are proposing the alternatives of (i) use of 
input-based methodology for each test, (ii) use of output-based 
methodology for each test, or (iii) allowing the source to choose 
between input- or output-based methodology. Some commenters strongly 
opposed an output-based format, believing that it would encourage 
emissions increases. We believe these concerns are mitigated in a 
system where total annual emissions

[[Page 26206]]

are capped nationally. Other commenters supported the output-based 
format, noting that it would encourage energy efficiency.
---------------------------------------------------------------------------

    \4\ In this context, we use the term ``input'' as a convenient 
way to refer to the hourly emission rate test, and to distinguish it 
from the output test, which is calculated on the basis of hourly 
emissions per kilowatt hour of generation.
---------------------------------------------------------------------------

    We agree that an output-based test encourages efficient units, 
which has well-recognized benefits. The more efficient an EGU, the less 
it emits for a given period of operation. For example, a 50 MW 
combustion turbine that operates 500 hours a year, for 25,000 MWh per 
year at an emission rate of 75 ppm, would emit 46 tons per year at 25 
percent efficiency, 41 tons per year at 28 percent efficiency, 37 tons 
per year at 31 percent efficiency, and 34 tons per year at 34 percent 
efficiency.
    Furthermore, we have established pollution prevention as one of our 
highest priorities. One of the opportunities for pollution prevention 
is maximizing the efficiency of energy generation. An output-based 
standard establishes emission limits in a format that incorporates the 
effects of unit efficiency by relating emissions to the amount of 
useful energy generated, not the amount of fuel burned. By relating 
emission limitations to the productive output of the process, output-
based emission limits encourage energy efficiency because any increase 
in overall energy efficiency results in a lower emission rate. Allowing 
energy efficiency as a pollution control measure provides regulated 
sources with an additional compliance option that can lead to reduced 
compliance costs as well as lower emissions. The use of more efficient 
technologies reduces fossil fuel use and leads to multi-media 
reductions in environmental impacts both on-site and off-site. On-site 
benefits include lower emissions of all products of combustion, 
including hazardous air pollutants, as well as reducing any solid waste 
and wastewater discharges. Off-site benefits include the reduction of 
emissions and non-air environmental impacts from the production, 
processing, and transportation of fuels.
    While output-based emission limits have been used for regulating 
many industries, input-based emission limits have been the traditional 
method to regulate steam generating units. However, this trend is 
changing as we seek to promote pollution prevention and provide more 
compliance flexibility to combustion sources. For example, in 1998 we 
amended the NSPS for electric utility steam generating units (40 CFR 
part 60, subpart Da) to use output-based standards for nitrogen oxides 
(NOX ; 40 CFR 63.44a, 62 FR 36954, and 63 FR 49446). We 
recently promulgated new output-based emission limits for sulfur 
dioxide (SO2) and NOX under subpart Da of 40 CFR 
part 60 (71 FR 9866) and for combustion turbines. (71 FR 38482.)

B. Option 2: Hourly Emissions Increase Test

    For Option 2, we are proposing a maximum achieved emissions 
increase test alternative and a maximum achievable emissions increase 
test alternative. For both the maximum achieved and maximum achievable 
emissions increase test, we are also proposing the alternatives of (i) 
the use of input-based methodology for each test; (ii) the use of 
output-based methodology for each test, or (iii) allowing the source to 
choose between input- or output-based methodology. We describe these 
alternatives in detail in Section V. of this preamble.
    Option 2 with the proposed maximum hourly achieved test would 
simplify NSR applicability determinations. Option 2 with the proposed 
maximum hourly achievable test provides even more simplicity by 
conforming NSR applicability determinations to NSPS applicability 
determinations. We also note the achieved and achievable tests 
eliminate the burden of projecting future emissions and distinguishing 
between emissions increases caused by the change from those due solely 
to demand growth, because any increase in the emissions under the 
hourly emissions tests would logically be attributed to the change. 
Both the achieved and achievable tests reduce recordkeeping and 
reporting burdens on sources because compliance will no longer rely on 
synthesizing emissions data into rolling average emissions. Option 2 
would reduce the reviewing authorities' compliance and enforcement 
burden compared to the current regulations.
    In the October 2005 NPR, we also solicited comment on whether, if 
we revised the NSR test to be a maximum achieved emissions test or 
output-based emissions test, we should revise the NSPS regulations to 
include a maximum achieved emissions test or an output-based emissions 
test. This SNPR concerns the emissions test for existing EGUs in the 
major NSR programs. It does not address the emissions test for existing 
EGUs under the NSPS program.

III. Analyses Supporting Proposed Options

    We examined how our proposed options for major NSR applicability 
for EGUs would affect control technology installation, emissions, and 
air quality. We conducted two separate analyses using the Integrated 
Planning Model (IPM). Our analyses show that none of the proposed 
options would have a detrimental impact on county-level emissions or 
local air quality. This section discusses our analyses and findings. 
More extensive information on our analyses is available in the 
Technical Support Document, which is available in Docket ID No. EPA-HQ-
OAR-2005-0163.

A. The Integrated Planning Model

    We use the IPM to analyze the projected impact of environmental 
policies on the electric power sector in the 48 contiguous States and 
the District of Columbia. The IPM is a multi-regional, dynamic, 
deterministic linear programming model of the entire electric power 
sector. It provides forecasts of least-cost capacity expansion, 
electricity dispatch, and emission control strategies for meeting 
energy demand and environmental, transmission, dispatch, and 
reliability constraints. We have used the IPM extensively to evaluate 
the cost and emissions impacts of proposed policies to limit emissions 
of sulfur dioxide and nitrogen oxides from the electric power sector. 
The IPM was a key analytical tool in developing the Clean Air 
Interstate Regulation (CAIR; see 70 FR 25162). However, the IPM 
capabilities and results are not limited to projections for CAIR 
States. It includes data for and projects emissions and controls for 
the electric sector in the contiguous United States.
    Each IPM model run is based on emissions controls on existing 
units, State regulations, cost and performance of generating 
technologies, SO2 and NOX heat rates, natural gas 
supply and prices, and electricity demand growth assumptions. This 
input is updated on a regular basis. We used the IPM to project EGU 
SO2 and NOX controls, emissions, and air quality 
in 2020 considering projected emission controls under the CAIR, Clean 
Air Mercury Rule (CAMR), and Clean Air Visibility Rule (CAVR). For 
convenience, we refer to this projection as the CAIR/CAMR/CAVR 2020 
Base Case Scenario or, more simply, the Base Case Scenario. The IPM 
model used for this scenario is IPM v.2.1.9.\5\
---------------------------------------------------------------------------

    \5\ Complete documentation for IPM, including the Base Case 
Scenario, is available at https://www.epa.gov/airmarkets/progsregs/
epa-ipm/. See also Docket EPA-HQ-OAR-2005-0163, DCN 01.
---------------------------------------------------------------------------

    The IPM v 2.1.9 is based on 2,053 model plants, which represent 
13,819 EGUs, including 1,242 coal-fired EGUs.\6\ This represents all 
existing EGUs in the

[[Page 26207]]

contiguous United States as of 2004, as well as new units that are 
already planned or committed, and new units that are projected to come 
online by 2007. The underlying data for these plants is contained in 
the National Electric Energy Data System (NEEDS), which contains 
geographic location, fuel use, emissions control, and other data on 
each existing EGU. NEEDS data for existing EGUs comes from a number of 
sources, including information submitted to EPA under the Title IV Acid 
Rain Program and the NOX Budget Program, as well as 
information submitted to the Department of Energy's (DOE's) Energy 
Information Agency, on Forms EIA 860 and 767. That is, the underlying 
data for each existing EGU in the IPM v.2.1.9 is information from an 
actual EGU in operation as of 2004 that has been submitted to the EPA 
or the DOE.
---------------------------------------------------------------------------

    \6\ See the NEEDS 2004 documentation for IPM v.2.1.9 in Exhibit 
4-6, which can be found at https://www.epa.gov/airmarkets/progsregs/
epa-ipm/past-modeling.html. See also Docket EPA-HQ-OAR-2005-0163, 
DCN 02.
---------------------------------------------------------------------------

    The IPM v.2.1.9 model also accounts for growth in the EGU sector 
that is projected to occur through new builds, including both planned-
committed units and potential units. Planned-committed EGUs are those 
that are likely to come online, because ground has been broken, 
financing obtained, or other demonstrable factors indicate a high 
probability that the EGU will come online. Planned-committed units in 
IPM v.2.1.9 were based on two information sources: RDI NewGen database 
(RDI) distributed by Platts (https://www.platts.com) and the inventory 
of planned-committed units assembled by DOE, Energy Information 
Administration, for their Annual Energy Outlook. Potential EGUs are 
those units that may be built at a future date in response to 
electricity demand. In IPM v.2.1.9, potential new units are modeled as 
additional capacity and generation that may come online in each model 
region.
    IPM v.2.1.9 also accounts for emission limitations due to State 
regulations and enforcement actions. It includes State regulations that 
limit SO2 and NOX emissions from EGUs. These are 
included in Appendix 3-2, available at https://www.epa.gov/airmarkets/
progsregs/epa-ipm/docs/bc3appendix.pdf.\7\ The IPM v.2.1.9 includes NSR 
settlement requirements for the following six utility companies: 
SIGECO, PSEG Fossil, TECO, We Energies (WEPCO), VEPCO and Santee 
Cooper. The settlements are included as they existed on March 19, 2004. 
A summary of the settlement agreements is included in Appendix 3-3 of 
the IPM documentation and is available https://www.epa.gov/airmarkets/
progsregs/epa-ipm/docs/bc3appendix.pdf.\8\
_____________________________________-

 \7\ See also Docket EPA-HQ-OAR-2005-0163, DCN 03.
    \8\ See also Docket EPA-HQ-OAR-2005-0163, DCN 03.
---------------------------------------------------------------------------

    In the IPM, EPA does not attempt to model unit-specific decisions 
to make equipment change or upgrades to non-environmental related 
equipment that could affect efficiency, availability or cost to operate 
the unit (and thus the amount of generation). Modeling such decisions 
would require either obtaining or making assumptions about the 
condition of equipment at units and would greatly increase model size, 
limiting its applicability in policy analysis. Specifically, IPM does 
not project that any particular existing EGU will make physical or 
operational changes that increase its efficiency, generation, or 
emissions. Therefore, IPM does not predict which particular EGUs will 
be subject to the major NSR applicability requirements. However, as 
discussed below, EPA has specially designed inputs to IPM that provide 
useful information directly related to major NSR applicability 
requirements. As we discuss below, these inputs are in the form of 
constraints to the IPM model rather than changes on a unit-by-unit 
basis.
    Reliability is a critical element of power plant operation. 
Reliability is generally defined as whether an EGU is able to operate 
over sustained periods at the level of output required by the utility. 
One measure of reliability is availability, the percentage of total 
time in a given period that an EGU is available to generate 
electricity. An EGU is available if it is capable of providing service, 
regardless of the capacity level that can be provided. Availability is 
generally measured using the number of hours that an EGU operates 
annually. For example, if an EGU operated 8,760 hours in a particular 
year, it was 100 percent available. Each year, EGUs are not available 
for some number of hours due to planned outages, maintenance outages, 
and forced outages.
    IPM v.2.1.9 uses information from the North American Electric 
Reliability Council (NERC)'s Generator Availability Data System (GADS) 
to determine the annual availability for EGUs. The GADS database 
includes operating histories--some dating back to the early 1960's--for 
more than 6,500 EGUs. These units represent more than 75 percent of the 
installed generating capacity in the United States and Canada. Each 
utility provides reports, detailing its units' operation and 
performance. The reports include types and causes of outages and 
deratings, unit capacity ratings, energy production, fuel use, and 
design information. GADS provides a standard set of definitions for 
determining how to classify an outage on a unit, including planned 
outages, maintenance outages, and forced outages. The GADS data are 
reported and summarized annually. A planned outage is the removal of a 
unit from service to perform work on specific components that is 
scheduled well in advance and has a predetermined start date and 
duration (for example, annual overhaul, inspections, testing). Turbine 
and boiler overhauls or inspections, testing, and nuclear refueling are 
typical planned outages.
    A maintenance outage is the removal of a unit from service to 
perform work on specific components that can be deferred beyond the end 
of the next weekend, but requires the unit be removed from service 
before the next planned outage. Typically, maintenance outages may 
occur any time during the year, have flexible start dates, and may or 
may not have predetermined durations. For example, a maintenance outage 
would occur if an EGU experiences a sudden increase in fan vibration. 
The vibration is not severe enough to remove the unit from service 
immediately, but does require that the unit be removed from service 
soon to check the problem and make repairs.
    A forced outage is an unplanned component failure or other 
breakdown that requires the unit be removed from service immediately, 
that is, within 6 hours, or before the end of the next weekend. A 
common cause of forced outages is boiler tube failure.
    Each EGU must report the number of hours due to planned outages, 
maintenance outages, and forced outages to NERC annually. NERC 
summarized the data for all coal-fired EGUs over the period from 2000-
2004 in its Annual Unit Performance Statistics Report.\9\ For the years 
2001-2004, the average annual planned outage hours for all coal-fired 
EGUs was 572.09 (about 23 days), the average annual maintenance outage 
hours for all coal-fired EGUs was 156.27 (about 6 days), and the 
average annual forced outage hours for all coal-fired EGUs was 348.75 
(about 14 days). The total annual unavailable hours for all coal-fired 
EGUs were 1,087.57, which is 15.1 percent of the total annual hours of 
8,760. Based on this data, the IPM v.2.1.9 assumed coal-fired EGUs were 
85 percent available. As just noted, of the 1,087.57 total unavailable 
hours, 348.75 were forced outage hours, which means that coal-fired 
EGUs were

[[Page 26208]]

unavailable due to forced outages approximately 4 percent of the hours 
in a year for the years 2000-2004.
---------------------------------------------------------------------------

    \9\ The report is available at https://www.nerc.com/~gads/ and in 
Docket EPA-HQ-OAR-2005-0163, DCN 04.
---------------------------------------------------------------------------

    We recently released a graphic presentation of electric power 
sector results under CAIR/CAMR/CAVR. Entitled ``Contributions of CAIR/
CAMR/CAVR to NAAQS Attainment: Focus on Control Technologies and 
Emission Reductions in the Electric Power Sector,'' it is available at 
https://www.epa.gov/cair/charts.html.\10\ As this presentation shows, 
under the CAIR/CAMR/CAVR 2020 Base Case Scenario, local SO2 
and NOX emissions generally decrease, average SO2 
and NOX emission rates decrease, and national SO2 
and NOX emissions decrease. As this document also shows, 
half of the coal-fired generation is expected to have scrubbers and 
either SCR or SNCR by 2020. These effects occur throughout the 
contiguous 48 States, not just in the CAIR States.
---------------------------------------------------------------------------

    \10\ Also available in Docket EPA-HQ-OAR-2005-0163, DCN 05.
---------------------------------------------------------------------------

    We developed IPM scenarios to examine the effects of our proposed 
regulations, including the maximum hourly emissions increase tests 
(achievable and achieved, on an input and output basis), on EGU 
emissions and control technologies. These new IPM scenarios incorporate 
the parameters used in the IPM model v.2.1.9 that we describe above, 
including information for the electric sector in the contiguous United 
States. Thus, these new IPM scenarios revise the parameters in the 
CAIR/CAMR/CAVR 2020 Base Case Scenario consistent with the way EGUs 
might operate under the proposed major NSR applicability changes. We 
call these IPM scenarios the NSR Availability and the NSR Efficiency 
Scenarios, and discuss them in the following sections.

B. NSR Availability Scenarios--Description of the Scenarios

    We developed two IPM scenarios, which we call the CAIR/CAMR/CAVR 
NSR Availability Scenarios, or, more simply, the NSR Availability 
Scenarios, to examine how changes to major NSR applicability under the 
proposed regulations could, by allowing sources to make repairs or 
improvements that increase hours of operation, affect emissions and 
control technology installation. The NSR Availability IPM scenarios are 
based on the CAIR/CAMR/CAVR 2020 Scenario.
    The primary difference between the current applicability test and 
the proposed tests is that under the proposed tests, sources could more 
readily make repairs or improvements that prevent forced outages, and 
thereby allow the source to operate more hours. These repairs allow the 
source to operate at the higher availability level that it achieved 
before its equipment degraded so much as to cause more forced outages.
    Some commenters emphasized this difference between the current 
applicability test and our proposals in the NPR. They explained that 
because, as we noted at 70 FR 61100, hours of operation are considered 
in determining annual emissions under the actual-to-projected-actual 
test in the current major NSR program but have no role in any of our 
proposed hourly emissions increase test options, an EGU could make a 
change that does not increase the maximum hourly emissions rate, but 
does allow the source to run more hours. This change would not trigger 
review under a maximum hourly emissions increase test in any case, but 
in some cases might trigger review under the current major NSR 
emissions increase test based on annual emissions with a 5-year 
baseline period. These commenters assert that the proposed 
applicability tests could allow substantial increases in annual 
emissions without triggering NSR.
    For several reasons, we believe commenters have overstated the 
likelihood that substantial increases in annual emissions and resulting 
deterioration in air quality would occur under the proposed maximum 
hourly emissions tests, as opposed to the current annual emissions, 5-
year baseline test. First, an EGU can increase its hours of operation 
under the current regulations, as long as it does not make a physical 
change or change in the method of operation. Information from the RBLC 
confirms that most EGUs are already permitted to run 8760 hours 
annually. That is, increases in hours of operation at most EGUs are not 
a change in the method of operation. They are allowed and frequently 
occur at many EGUs under the current regulations without triggering 
major NSR. Second, increases in actual emissions stemming from 
increases in hours of operation that are unrelated to the change, are 
not considered in determining projected actual emissions. To the extent 
that changes resulting in increased hours would occur under the 
proposed regulatory scheme, any resulting increases in emissions will 
be diminished as the CAIR and BART programs are implemented and the 
SO2 and NOX emissions for most EGUs are capped. 
As we described in detail in the NPR, 70 FR 61087, national and 
regional caps limit total actual annual EGU SO2 and 
NOX emissions. These caps greatly reduce the significance of 
hours of operations on actual emissions from the sector nationally. 
Furthermore, as we indicated in our recent report of the CAIR/CAMR/
CAVR, the more hours an EGU operates, the more likely it is to install 
controls.\11\ Moreover, existing synthetic minor limits to avoid major 
NSR and enforceable limits on hours of operation on a particular EGU as 
a result of netting would remain in place under any revised emissions 
increase test. We thus believe the opportunities for many EGUs to 
significantly increase their emissions through higher hours of 
operation under a maximum hourly emissions increase test, as compared 
to the current annual emissions increase test with a 5-year baseline 
period, are generally limited.
---------------------------------------------------------------------------

    \11\ See our presentation, ``Contributions of CAIR/CAMR/CAVR to 
NAAQS Attainment: Focus on Control Technologies and Emission 
Reductions in the Electric Power Sector,'' on pages 39 and 43. The 
presentation is available at https://www.epa.gov/cair/charts.html. 
Also available in Docket EPA-HQ-OAR-2005-0163, DCN 05.
---------------------------------------------------------------------------

    Nonetheless, we want to comprehensively examine the outcomes of a 
maximum hourly emissions increase test, using a robust methodology 
based on conservative (that is, protective of the environment) 
estimates. We therefore developed two IPM scenarios, which we call the 
CAIR/CAMR/CAVR NSR Availability Scenarios, or, more simply, the NSR 
Availability Scenarios, to examine how changes to major NSR 
applicability under the proposed regulations could, by allowing sources 
to make repairs or improvements that increase hours of operation, 
affect emissions and control technology installation. These IPM 
scenarios are based on the CAIR/CAMR/CAVR 2020 Scenario, which employs 
the IPM v.2.1.9 model that we describe in Section III. A. of this 
preamble, including information for the electric sector in the 
contiguous United States. Section III A. of this document also contains 
specific information on the assumptions about EGU assumptions in the 
IPM v.2.1.9. The NSR Availability Scenarios retain the heat input for 
each EGU from the CAIR/CAMR/CAVR 2020 Scenario. That is, we did not 
assume that any existing EGU would increase its capacity in the NSR 
Availability Scenario.
    The parameters in the IPM model are based on availability for 6,500 
EGUs over the 5-year period from 2000-2004. In the NSR Availability 
scenarios, however, we changed the parameters in IPM v.2.1.9 consistent 
with the way EGUs might operate under the more flexible regulations 
that we are proposing. That is, we assumed that

[[Page 26209]]

some owner/operators might make changes that increase the hours of 
operation of some EGUs. It is unlikely that an owner/operator would be 
able to make changes that reduce the hours that an EGU is unavailable 
due to a planned outage or a maintenance outage. However, EGUs would be 
able to make changes that increase their hours of operation as a result 
of a reduction in the number and length of forced outages. 
Specifically, with more flexibility concerning the number of hours EGUs 
operate annually, EGU owner/operators may replace broken-down equipment 
in an effort to reduce the number of forced outages. Such actions would 
increase the safety, reliability, and efficiency of EGUs, consistent 
with one of our primary policy goals for our proposed regulations.
    Therefore, in the NSR Availability Scenario, we assumed that coal-
fired EGUs would be able to make changes that affect forced outage 
hours in two, alternative, ways: (1) Coal-fired EGUs would reduce their 
forced outage hours by half (2 percent increase in availability); and 
(2) coal-fired EGUs would have no forced outage hours (4 percent 
increase in availability). Therefore, in the first model run, we 
increased the coal-fired availability by 2 percent, from 85 percent to 
87 percent annually. In the second NSR EGU run, we increased coal-fired 
availability by 4 percent, to 89 percent annually. We believe it is 
unlikely that an EGU would be able to make repairs that completely 
eliminate forced outage hours. However, we wanted a robust examination 
of changes that could impact emissions and air quality.\12\ We 
therefore made the very conservative assumption to increase to EGU 
availability by 2 percent and 4 percent over the actual historical 
hours of operation for 6,500 EGUs over the years 2000-2004. All other 
information in the NSR Availability Scenarios is the same as that in 
IPM v.2.1.9 used for the CAIR/CAMR/CAVR Scenario.
---------------------------------------------------------------------------

    \12\ While we believe it is most likely that an EGU would 
increase its hours of operation under these proposed regulations due 
to reducing the number of hours that the EGU is unavailable due to 
forced outage hurs, the analysis is applicable to increaes in hours 
of operation for other reasons.
---------------------------------------------------------------------------

    The NERC GADS calculates the average availability for an EGU by 
taking the actual total number of unavailable hours in a given year for 
all EGUs and dividing it evenly among the total number of EGUs. Based 
on the GADS data, the IPM assumes an upper bound of 85 percent 
availability for coal-fired EGUs. In GADS data for the years 2000-2004, 
some EGUs actually had more than 85 percent availability and some 
actually had less. The particular EGUs that had greater than 85 percent 
availability and less than 85 percent varied from year to year. 
Similarly, by eliminating forced outages, some EGUs could increase 
their availability by more than 2-4 percent and some EGUs could 
increase their availability by less than 2-4 percent. Likewise, the 
particular EGUs that were able to reduce their forced outage hours 
would also vary from year to year. For modeling purposes, it thus makes 
more sense to assume an average availability than to determine unit-by-
unit availabilities for each and every EGU in a given year.
    Our approach based on average availability is also consistent with 
actual historical operations at particular EGUs and plantsites, which 
are most directly related to local emissions and air quality. Variation 
in actual annual hours of operation at a given EGU and at given 
plantsites do occur under current major NSR applicability. It is not 
uncommon for actual hours of operation for a particular EGU to vary by 
348 hours (4 percent availability) or more from year to year. It is 
also not uncommon for the variation in actual hours of operation to 
occur among EGUs at a particular plantsite by 4 percent or more from 
year to year. For example, in one year Unit A might run 7,800 hours and 
Unit B might run 7,400 hours. In the next year Unit B might run 7,800 
hours and Unit A 7,400 hours. This pattern further supports an approach 
based on average availability for estimating local emissions. Changes 
in average availability, rather than the absolute availability of any 
given EGU, thus is appropriate for analyzing the impact of proposed 
changes to major NSR applicability.

C. NSR Availability Scenarios--Discussion of SO2 and NOX Results

    This section discusses the SO2 and NOX 
control device installation, national emissions, local emissions, and 
impact on air quality for EGUs under the NSR Availability Scenario.
    1. SO2 and NOX Control Device Installation. As Table 2 shows, the 
NSR Availability Scenarios project retrofitting of more control devices 
than under the CAIR/CAMR/CAVR 2020 Scenario.\13\ This result occurs 
whether hours of operation increase by 2 percent or by 4 percent. 
Significantly, under the 4 percent scenario, more Gigawatts (GW) of 
electric capacity are controlled than under the 2 percent scenario. For 
example, under NSR Availability 4%, there is 3.63 more GW of national 
EGU capacity with scrubbers than under CAIR/CAMR/CAVR 2020. These 
results are consistent with what IPM generally projects, as noted 
above; that is, the more hours an EGU operates, the more likely it is 
to install controls.\14\ We thus conclude that the more hours an EGU 
operates, the more likely it is to install controls, regardless of 
whether the major NSR applicability test is on an hourly basis or an 
annual basis.
---------------------------------------------------------------------------

    \13\ Available in Docket EPA-HQ-OAR-2005-0163, DCN 06. (System 
Summary Report for NSR Availability).
    \14\ See our presentation, ``Contributions of CAIR/CAMR/CAVR to 
NAAQS Attainment: Focus on Control Technologies and Emission 
Reductions in the Electri Power Sector,'' on pages 39 and 43. The 
presentation is available at https://www.epa.gov/cair/charts.html. 
Also available in Docket EPA-HQ-OAR-2005-0163, DCN 05.

[[Page 26210]]



              Table 2.--2020 National EGUs With Emission Controls Under NSR Availability Scenarios
----------------------------------------------------------------------------------------------------------------
                                  EGUs with additional controls      EGUs with additional controls compared to
                                   compared to 2004 base case                   CAIR/CAMR/CAVR 2020
   Emission  control  type    ----------------------------------------------------------------------------------
                               NSR availability  NSR availability  NSR availability
                                      2%                4%                2%             NSR availability 4%
----------------------------------------------------------------------------------------------------------------
FGD\15\......................  109.62 GW.......  111.53 GW.......  1.71 GW.........  3.63 GW
SCR\16\......................  73.47 GW........  73.92 GW........  0.62 GW.........  1.07 GW
----------------------------------------------------------------------------------------------------------------

    2. SO2 and NOX National Emissions. As Table 3 shows, the NSR 
Availability Scenarios project essentially no changes in SO2 
or NOX emissions nationally by 2020 as compared to emissions 
under the CAIR/CAMR/CAVR 2020 Scenario.\17\ This result is consistent 
with the fact that under the NSR Availability Scenarios, the amount of 
controls increases, compared to CAIR/CAMR/CAVR 2020, and we find that 
these associated emissions decreases are offset by the emissions 
increases associated with the reduced forced outages and higher 
production levels.
---------------------------------------------------------------------------

    \15\ 15 FGD is flue gas desulfurization, also known as 
scrubbers, for control of SO2 emissions.
    \16\ SCR is selective catalytic reduction, used for control of 
NO