```

[Federal Register Volume 77, Number 52 (Friday, March 16, 2012)]
[Proposed Rules]
[Pages 15656-15664]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-6429]

=======================================================================
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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 51 and 52

[EPA-HQ-OAR-2003-0062; FRL-9648-1]
RIN 2060-AR30

Implementation of the New Source Review (NSR) Program for 
Particulate Matter Less Than 2.5 Micrometers (PM2.5): 
Amendment to the Definition ``Regulated NSR Pollutant'' Concerning 
Condensable Particulate Matter

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The EPA is proposing to revise the definition ``regulated NSR 
pollutant'' contained in two sets of Prevention of Significant 
Deterioration (PSD) regulations and in the EPA's Emission Offset 
Interpretative Ruling. This revision would correct an inadvertent error 
made in 2008 when the EPA issued its final rule to implement the new 
source review (NSR) program for fine particles with an aerodynamic 
diameter of less than or equal to 2.5 micrometers (PM2.5). 
Effectively, this revision would reestablish the interpretation that 
for measurement of ``particulate matter emissions'' in the context of 
the PSD and NSR regulations there is no explicit requirement to include 
measurement of condensable PM. However, the condensable portion would 
continue to be required for emissions of particles with an aerodynamic 
diameter of less than or equal to 10 micrometers (PM10) and 
PM2.5.

DATES: Comments must be received on or before May 15, 2012.
    Public Hearing. If anyone contacts the EPA requesting the 
opportunity to speak at a public hearing concerning the proposed 
regulation by March 26, 2012, the EPA will hold a public hearing 
approximately 30 days after publication in the Federal Register. 
Additional information about the hearing would be published in a 
subsequent Federal Register notice.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2003-0062, by one of the following methods:
    http://www.regulations.gov. Follow the online instructions 
for submitting comments.
     Email: a-and-r-docket@epa.gov.
     Mail: Air and Radiation Docket, Environmental Protection 
Agency, Mail code 6102T, 1200 Pennsylvania Avenue NW., Washington, DC 
20460. Please include a total of two copies.
     Hand Delivery: EPA Docket Center, Public Reading Room, EPA 
West, Room 3334, 1301 Constitution Ave. NW., Washington, DC 20460. 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 the applicable docket. The 
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 www.regulations.gov or email. The 
www.regulations.gov Web site is an ``anonymous access'' system, which 
means the EPA will not know your identity or contact information unless 
you provide it in the body of your comment. If you send an email 
comment directly to the EPA without going through www.regulations.gov, 
your email address will be automatically captured and included as part 
of the comment that is placed in the public docket and made available 
on the Internet. If you submit an electronic comment, the 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 the 
EPA cannot read your comment due to technical difficulties and cannot 
contact you for clarification, the EPA may not be able to consider your 
comment. Electronic files should avoid the use of special characters, 
any form of encryption, and be free of any defects or viruses.
    Docket: All documents in the docket are listed in the 
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, is not placed on the Internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available either electronically through 
www.regulations.gov or in hard copy at the EPA Docket Center, Public 
Reading Room, EPA West, Room 3334, 1301 Constitution Ave. NW., 
Washington, DC 20460. 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) 566-1742, and the 
telephone number for the Air Docket is (202) 566-1744.

FOR FURTHER INFORMATION CONTACT: Mr. Dan deRoeck, Air Quality Policy 
Division (C504-03), U.S. Environmental Protection Agency, Research 
Triangle Park, NC, 27711; telephone number (919) 541-5593; fax number 
(919) 541-5509; or email address: deroeck.dan@epa.gov.
    To request a public hearing or information pertaining to a public 
hearing on this document, contact Ms. Pamela Long, Air Quality Policy 
Division, Office of Air Quality Planning and Standards (C504-03), 
Environmental Protection Agency, Research Triangle Park, North Carolina 
27711; telephone number (919) 541-0641; fax number (919) 541-5509; 
email address: long.pam@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

    Entities affected by this rule include sources in all industry 
groups. The majority of sources potentially affected are expected to be 
in the following groups that emit particulate matter:

------------------------------------------------------------------------
             Industry group                         NAICS \a\
------------------------------------------------------------------------
Electric services......................  221111, 221112, 221113, 221119,
                                          221121, 221122
Petroleum refining.....................  32411

[[Page 15657]]

 
Industrial inorganic chemicals.........  325181, 32512, 325131, 325182,
                                          211112, 325998, 331311, 325188
Industrial organic chemicals...........  32511, 325132, 325192, 325188,
                                          325193, 32512, 325199
Miscellaneous chemical products........  32552, 32592, 32591, 325182,
                                          32551
Natural gas liquids....................  211112
Natural gas transport..................  48621, 22121
Pulp and paper mills...................  32211, 322121, 322122, 32213
Paper mills............................  322121, 322122
Automobile manufacturing...............  336111, 336112, 336712, 336211,
                                          336992, 336322, 336312, 33633,
                                          33634, 33635, 336399, 336212,
                                          336213
Pharmaceuticals........................  325411, 325412, 325413, 325414
------------------------------------------------------------------------
\a\ North American Industry Classification System.

    Entities affected by this rule also include state, local, and 
tribal reviewing authorities responsible for implementing Clean Air Act 
(CAA or Act) stationary source permitting programs.

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

    1. Submitting CBI. Do not submit information containing CBI to the 
EPA through www.regulations.gov or email. Send or deliver information 
identified as CBI only to the following address: Mr. Roberto Morales, 
OAQPS Document Control Officer (C404-02), U.S. EPA, Office of Air 
Quality Planning and Standards, Research Triangle Park, North Carolina 
27711, Attention: Docket ID EPA-HQ-OAR-2003-0062. 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 the 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.
    2. Tips for Preparing Your Comments. When submitting your 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.
     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. 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 proposed rule will also be available on the World Wide Web. 
Following signature by the EPA Administrator, a copy of this proposed 
rule will be posted in the regulations and standards section of our NSR 
home page located at http://www.epa.gov/nsr.

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

    To request a public hearing or information pertaining to a public 
hearing on this document, contact Ms. Pamela Long, Air Quality Policy 
Division, Office of Air Quality Planning and Standards (C504-03), 
Environmental Protection Agency, Research Triangle Park, North Carolina 
27711; telephone number (919) 541-0641; fax number (919) 541-5509; 
email address: long.pam@epa.gov.

E. How is this preamble organized?

    The information in this Supplementary Information section of this 
preamble is organized as follows:

I. General Information
    A. Does this action apply to me?
    B. What should I consider as I prepare my comments for EPA?
    C. Where can I get a copy of this document and other related 
information?
    D. How can I find information about a possible public hearing?
    E. How is this preamble organized?
II. Purpose
III. Background
    A. National Ambient Air Quality Standards (NAAQS) for 
Particulate Matter (PM)
    B. Measuring and Reporting Emissions of Pariculate Matter (PM)
    C. New Source Review Program for PM
IV. Why is the EPA proposing to change the definition ``Regulated 
NSR pollutant'' with regard to PM?
V. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    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
VI. Statutory Authority

II. Purpose

    The purpose of this rulemaking is to revise the definition 
``regulated NSR pollutant'' contained in the regulations for PSD at 40 
CFR 51.166 and 52.21, and in the EPA's Emission Offset Interpretative 
Ruling at 40 CFR part 51 Appendix S. This revision will correct an 
error that occurred when the regulations were revised in 2008. The 
existing definition was changed in 2008 to require that particulate 
matter emissions, PM10 emissions and PM2.5 
emissions--representing three separate size ranges or indicators of 
particles--must include ``gaseous emissions from a source or activity 
which condense to form particulate matter at ambient temperatures,'' 
i.e., condensable particulate matter. See existing 40 CFR 51.166 
(b)(49)(vi) and 52.21(b)(50)(vi). Previously, EPA's regulations did not 
require particulate matter emissions to include condensable particulate 
matter; consistent with the applicable New

[[Page 15658]]

Source Performance Standards (NSPS) for PM and the corresponding 
compliance test method, only the filterable fraction had been 
considered for NSR purposes. The 2008 change therefore imposed an 
unintended new requirement on state and local agencies and the 
regulated community. As described in more detail in section IV of this 
preamble, in the 2008 final rule we did not intend that the term 
``particulate matter emissions'' include the condensable PM fraction of 
primary PM; the EPA no longer regulates the ambient indicator, total 
suspended particulate (TSP), with which the indicator ``particulate 
matter emissions'' was originally associated, and there is no 
compelling reason for requiring that the condensable PM portion be 
counted toward the measure of ``particulate matter emissions'' from 
stationary sources for PSD applicability determinations and in 
establishing emissions limitations.
    If these proposed revisions are finalized, they will ensure that 
our approach for regulating the three indicators for particulate matter 
under the PSD program is codified as originally intended. This would 
mean that ``PM10 emissions'' and ``PM2.5 
emissions'' would be regulated as criteria pollutants (that is, under 
the portion of the definition that refers to ``[a]ny pollutant for 
which a national ambient air quality standard has been promulgated * * 
*''), and would be required to include the condensable PM fraction 
emitted by a source. Also, ``particulate matter emissions'' would be 
regulated as a non-criteria pollutant (that is, under the portion of 
the definition that refers to ``[a]ny pollutant that is subject to any 
standard promulgated under section 111 of the Act''), without a general 
requirement to include the condensable PM fraction emitted by a source.

III. Background

A. National Ambient Air Quality Standards (NAAQS) for Particulate 
Matter (PM)

    Sections 108 and 109 of the CAA govern the establishment and 
revision of the NAAQS. Section 108 directs the Administrator to 
identify and list ``air pollutants'' that ``in his judgment, may 
reasonably be anticipated to endanger public health and welfare'' and 
whose ``presence * * * in the ambient air results from numerous or 
diverse mobile or stationary sources'' and to issue air quality 
criteria for those pollutants that are listed. Section 109 directs the 
Administrator to propose and promulgate primary and secondary NAAQS for 
pollutants listed under section 108 to protect public health and 
welfare, respectively. Section 109 also requires review of the NAAQS at 
5-year intervals.
    ``Particulate matter'' is a term used to define an air pollutant 
that consists of a mixture of solid particles and liquid droplets found 
in the ambient air. Particulate matter occurs in many sizes and shapes 
and can be made up of hundreds of different chemicals. As explained 
further in the discussion that follows, the EPA has regulated several 
size ranges of particles, e.g., PM2.5, referred to as 
indicators of particles \1\, which has required that test methods be 
developed to capture the appropriate size particles that occur in the 
ambient air or that are being emitted directly from a source. In some 
cases, the EPA regulates certain species of particles as separate ``air 
pollutants.'' For example, lead, beryllium, fluorides, and sulfuric 
acid mist are constituents of particulate matter that are also 
regulated separately under New Source Performance Standards (40 CFR 
part 60) or National Emissions Standards for Hazardous Air Pollutants 
(40 CFR parts 61, 63 or 65).
---------------------------------------------------------------------------

    \1\ The ``indicator'' of a standard defines the chemical species 
or mixture that is to be measured in determining whether an area (in 
the case of an ambient standard) or a source (in the case of an in-
stack standard) attains that standard.
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    Particles as measured in the ambient air consist of both primary 
and secondary particles. Primary particles are emitted directly from 
sources, and may include gaseous emissions, which, when emitted from 
the stack of a source, condense under ambient conditions to form 
particles. Primary particles directly emitted by a source as a solid or 
liquid at the stack and captured on the filter of a test train are 
referred to as the ``filterable'' PM fraction. The gaseous emissions 
that form particles upon condensing under ambient conditions following 
release from the stack are referred to as ``condensable'' PM. Other 
types of particles, known as secondary particles, are formed from 
precursors of PM, e.g., SO2 and NOX, at a 
distance from their point of release as a result of complex reactions 
in the atmosphere.
    Initially, the EPA established NAAQS for PM on April 30, 1971, 
under sections 108 and 109 of the Act. See 36 FR 8186. Compliance with 
the original PM NAAQS was based on the measurement of particles in the 
ambient air using an indicator of particles measuring up to a nominal 
size of 25 to 45 micrometers ([mu]m) in the ambient air. The EPA used 
the indicator name ``total suspended particulate'' or ``TSP'' to define 
the particle size range that was being measured. Total suspended 
particulate remained the indicator for the PM NAAQS until 1987 when the 
EPA revised the NAAQS in part by replacing the TSP indicator for both 
the primary and secondary standards with a new indicator that includes 
only those particles with an aerodynamic diameter smaller than or equal 
to a nominal 10 [mu]m (PM10).
    On July 18, 1997, the EPA made significant revisions to the PM 
NAAQS in several respects. While the EPA determined that the PM NAAQS 
should continue to focus on particles less than or equal to 10 [micro]m 
in diameter, the EPA also determined that the fine and coarse fractions 
of PM10 should be considered separately. Accordingly, on 
July 18, 1997, the EPA added a new indicator for fine particles with a 
nominal mean aerodynamic diameter less than or equal to 2.5 [mu]m 
(PM2.5), and continued to use PM10 as the 
indicator for purposes of regulating the coarse fraction of 
PM10. See 62 FR 38652.
    In the next periodic review, the EPA concluded, on October 17, 
2006, that it was necessary to revise the primary and secondary NAAQS 
for PM to provide increased protection of public health and welfare. 
See 71FR 61144. The EPA retained the two separate indicators--
PM10 and PM2.5--for determining compliance with 
the revised standards for PM, so both continue to be regarded as 
criteria pollutants.

B. Measuring and Reporting Emissions of Particulate Matter (PM)

    Section 110 of the Act requires that state and local air pollution 
control agencies develop and submit plans, known as state 
implementation plans or SIPs, for the EPA approval that provide for the 
attainment, maintenance and enforcement of the NAAQS. An essential 
component of each SIP is the emissions reduction strategy, including 
emissions limitations and other control measures (as set forth in SIPs 
and in individual source permits) designed to control the emissions of 
pollutants that contribute to the air quality against which the NAAQS 
are measured. For many years, most control measures for PM were 
generally focused on primary PM--specifically, the filterable PM 
fraction. Accordingly, the early EPA test methods for quantifying 
amounts of PM emitted by sources generally were based on the collection 
of the filterable PM fraction.
    In support of state obligations to develop emissions reduction 
strategies, section 111 of the Act requires the EPA to adopt 
technology-based standards of performance that focus on sources that 
cause or contribute significantly to ``air pollution which may 
reasonably be

[[Page 15659]]

anticipated to endanger public health and welfare.'' Such standards, 
referred to as NSPS, are emissions standards that are intended to 
reflect the degree of air pollution emission limitation attainable 
through the application of the best system of emission reduction 
(taking into account the cost of achieving such reduction and any non-
air quality health and energy requirements) that the Administrator 
determines has been adequately demonstrated. Accordingly, the EPA 
historically has developed NSPS (and corresponding compliance test 
methods) under 40 CFR part 60 to provide emissions standards that 
address, among other pollutants, the control of PM.
    When the EPA promulgated the first set of NSPS for PM in 1971, only 
the filterable PM fraction was regulated. The EPA simultaneously 
promulgated a test method, known as Method 5, as the NSPS compliance 
test method for PM. Once available, Method 5 was often also used for 
permitting purposes to quantify the in-stack PM emissions that 
represented the particles in the atmosphere expressed in terms of the 
ambient indicator, TSP--the original indicator for the PM NAAQS. Thus, 
the filterable PM emissions collected by Method 5 or other similar 
source test methods were sometimes referred to as ``TSP emissions,'' 
even though it was recognized that Method 5 actually collected 
particles that exceeded the TSP size range (25-45 [mu]m), and did not 
include the condensable PM fraction. Today, Method 5 continues to serve 
as the performance testing procedure for most NSPS for PM.
    With the promulgation of the PM10 NAAQS in 1987, the 
annual source emissions reporting of ``particulate matter emissions'' 
(required under 40 CFR 51.322 and 51.323) ended with the state 
reporting of calendar year 1987 emissions, and the required reporting 
of PM10 emissions began with state reporting of calendar 
year 1988 emissions. In the absence of a standard reference test 
method, states were instructed to choose an appropriate method of 
determining PM10 emissions for each source. On April 17, 
1990, the EPA promulgated Method 201A to provide the states with a 
standard means of measuring filterable PM10 emissions 
contained in the stack. Later in the same year, noting that condensable 
PM emissions form very fine particles in the PM10 size range 
and are considered PM10 emissions, the EPA proposed to add a 
test method to provide states with a means of measuring condensable PM 
emissions from stationary sources. See 55 FR 41546, October 12, 1990. 
The test method for condensable PM emissions, known as Method 202, was 
promulgated on December 17, 1991, in Appendix M of 40 CFR part 51. With 
the new focus on the PM10 indicator, the EPA also began to 
emphasize the relevance of condensable PM emissions,\2\ and encouraged 
states to consider the condensable PM fraction where it was considered 
to be a significant contributor to an area's PM10 
nonattainment status. However, there were only a few nonattainment 
areas where control of the condensable PM portion was actually required 
in order to achieve attainment.
---------------------------------------------------------------------------

    \2\ ``Condensable particulate matter is of potential importance 
because it usually is quite fine and thus falls primarily within the 
PM10 fraction.'' See, ``PM-10 SIP Development Guideline'' 
(June 1987) at p. 5-32.
---------------------------------------------------------------------------

    Even before the EPA's introduction of the PM2.5 
indicator for the PM NAAQS in 1997, the EPA published information on 
PM2.5 emissions in its National Emission Inventory Database 
(NEI).\3\ With the assistance of information gained through speciation 
analyses of PM2.5, the EPA recognized that condensable PM 
could be a substantial portion of the total PM2.5 emitted by 
certain source categories. Beginning with the 1999 NEI, the EPA began 
including the condensable PM fraction of the total PM2.5 
emitted by certain source categories, and encouraged states to consider 
the condensable PM fraction for the development of emissions 
inventories for PM2.5 SIPs.\4\ The EPA also provided 
condensable PM emission factors for various sources in AP-42 so that 
those state and local air control agencies having the responsibility to 
report emission inventories would have the tools needed to estimate and 
report those emissions to the EPA.
---------------------------------------------------------------------------

    \3\ The EPA's NEI contains information about sources that emit 
criteria pollutants and their precursors, and hazardous pollutants. 
The database includes estimates of annual air pollutant emissions 
from point, nonpoint and mobile sources. The NEI currently contains 
information on PM with regard to the criteria indicators 
PM10 and PM2.5.
    \4\ ``Emissions Inventory Guidance for Implementation of Ozone 
and Particulate Matter National Ambient Air Quality Standards 
(NAAQS) and Regional Haze,'' EPA-454/R-99-006 (April 1999).
---------------------------------------------------------------------------

    In 2002, the EPA issued a rule known as the Consolidated Emissions 
Reporting Rule (CERR), which, among other things, established 
requirements for the reporting to the EPA of PM2.5 
emissions. In conjunction with the new reporting requirements, the EPA 
added definitions of ``primary PM,'' ``primary PM10,'' and 
``primary PM2.5,'' all of which included both the filterable 
and condensable PM fraction. See 67 FR 39602, June 10, 2002. The CERR 
required states to report emissions of primary PM10 and 
primary PM2.5, and listed as optional the reporting of 
emissions of primary PM. However, when the EPA amended those rules in 
2008, it dropped the definition ``primary PM'' and the listing of 
``primary PM'' as an optional pollutant, eliminating the requirement 
for reporting ``PM'' (as opposed to PM10 and 
PM2.5). See 73 FR 76539, December 17, 2008.
    In November 2005, the EPA proposed requirements that states must 
fulfill in developing their implementation plans for the attainment of 
PM2.5 NAAQS. See 70 FR 65984, November 1, 2005. With the 
historical emphasis on controlling the filterable PM fraction--even 
when the shift occurred to control PM10 emissions--it became 
apparent that in many cases it could be necessary to take a closer look 
at the control of the condensable PM fraction in order to attain the 
PM2.5 NAAQS in some areas.\5\ The preamble highlighted the 
importance in certain cases of controlling the condensable PM fraction 
to help ensure the attainment of the new NAAQS. It was acknowledged at 
that time that most stationary source test methods specified in state 
rules did not provide for the measurement of condensable PM emissions. 
Instead, it was found that most source test methods referenced in SIPs 
provided a measurement of only the filterable fraction of PM. The EPA 
further noted that ``these filterable particulate matter test methods 
are either identical or very similar to one of the ten Federal test 
methods published in Appendix A of 40 CFR Part 60 and used to determine 
compliance with New Source Performance Standards (NSPS).'' Id at 66049. 
The EPA indicated that states needing to adopt local control measures 
for primary PM2.5 in nonattainment areas would need to 
revise their stationary source test methods to focus on the 
PM2.5 indicator, including the condensable PM fraction.\6\
---------------------------------------------------------------------------

    \5\ ``The inclusion of condensable emissions in a source's 
PM2.5 emissions is of increasing importance with the 
change in the indicator for particulate matter to PM2.5. 
Condensible emissions are essentially fine particles, and thus are a 
larger fraction of PM2.5 than of TSP or 
PM10.'' 70 FR 65984 (November 1, 2005) at p. 66039.
    \6\ The EPA did indicate that ``test methodologies that measure 
only filterable particulate matter would be acceptable in areas 
where no additional reductions of primary PM2.5 and 
particulate precursor emissions are required to project attainment 
of the PM2.5 NAAQS.'' Id at 66049.
---------------------------------------------------------------------------

    On March 25, 2009, the EPA proposed to modify existing Method 201A 
to allow for measurement of filterable PM2.5. In fact, the 
proposed modification offered the ability to measure filterable 
PM10, filterable PM2.5, or both filterable 
PM10 and filterable PM2.5 from

[[Page 15660]]

stationary sources. At the same time, the EPA proposed amendments to 
Method 202 to improve the precision of the method for measuring 
condensable PM and to provide for more accurate overall quantification 
of primary emissions of PM10 and PM2.5 to the 
ambient air. Method 202 contained several optional procedures that were 
intended to accommodate the various test methods used by state and 
local regulatory entities at the time Method 202 was being developed. 
The inclusion of the optional procedures in 1991 ultimately proved 
problematic in that each of them resulted in a different emissions 
value. To address this issue, the EPA explored the influence of the 
optional procedures to identify the ones that would result in a biased 
measurement. In December 2010, the EPA promulgated an improved Method 
202 eliminating options that would produce different measures of 
emissions.

C. New Source Review Program for PM

    The NSR program is a statutorily based preconstruction permitting 
program that applies when a stationary source of air pollution proposes 
to construct or undergo modification. The NSR program consists of three 
different preconstruction permit programs: (1) PSD; (2) nonattainment 
NSR; and (3) minor NSR. We often refer to the PSD and nonattainment NSR 
programs together as the major NSR program because those permit 
programs regulate the construction of new major stationary sources and 
major modifications to existing major stationary sources.
    The nonattainment NSR program applies in advance of construction to 
new major stationary sources and major modifications of sources of a 
pollutant that locate in an area that is designated ``nonattainment'' 
for that pollutant. As such, the nonattainment NSR program applies only 
with respect to criteria pollutants, i.e., pollutants (or indicators 
thereof) for which EPA has promulgated NAAQS. On the other hand, the 
PSD program is a statutorily based preconstruction review and 
permitting program that applies to new or modified major stationary 
sources proposing to locate in an area meeting the NAAQS 
(``attainment'' areas) and areas for which there is insufficient 
information to classify them as either attainment or nonattainment 
(``unclassifiable'' areas).
    Like the nonattainment NSR program, the applicability of the PSD 
program to a major stationary source or major modification must be 
determined in advance of construction and is pollutant-specific. 
However, unlike the nonattainment NSR program, the PSD requirements are 
applied on a pollutant-specific basis for any ``air pollutant'' that is 
``subject to regulation'' under the Act. Thus, the PSD program is not 
restricted to criteria pollutants.\7\ Once a major source is determined 
to be subject to the PSD program (PSD source) for a particular air 
pollutant, among other requirements, it must undertake a series of 
analyses to demonstrate that it will use the best available control 
technology (BACT) to minimize the emissions of each affected pollutant, 
and that the emissions of each pollutant will not cause or contribute 
to a violation of any applicable NAAQS or any applicable maximum 
allowable increase in a pollutant concentration (PSD increment).
---------------------------------------------------------------------------

    \7\ ``Particulate matter emissions'' are regulated under the PSD 
program as a regulated NSR pollutant, but not under the 
nonattainment NSR program because nonattainment designations apply 
only with regard to criteria pollutants (pollutants for which NAAQS 
exist, e.g., PM10 and PM2.5) and ``particulate 
matter emissions'' are not considered a criteria pollutant.
---------------------------------------------------------------------------

    Consistent with the original NAAQS and PSD increments for PM, the 
PSD program established pollutant applicability requirements for PM on 
the basis of the TSP indicator. Accordingly, the PSD regulations 
defined a ``significant'' increase in emissions of PM as 25 tons per 
year (tpy). When the EPA revised the PM NAAQS in 1987, establishing a 
new PM10 indicator, two indicators for particles were 
recognized as being regulated under the Act because the statutory PSD 
increments for PM were still expressed in terms of TSP. The addition of 
the new PM10 indicator also necessitated a distinction 
between those emissions of PM that should be used to determine a 
source's compliance with the new PM10 NAAQS and those 
emissions of PM that should be used to determine a source's compliance 
with the existing TSP-based increments. Hence, in 1987, the EPA adopted 
the term ``particulate matter emissions'' to help clarify the 
distinction between the original TSP indicator for the NAAQS and the 
new PM10 indicator. See 52 FR 24672, July 1, 1987. 
Accordingly, the original significant emissions rate of 25 tpy was 
retained and applied to the newly-defined term ``particulate matter 
emissions'' (associated with the ambient TSP indicator), and 
simultaneously a significant emissions rate of 15 tpy was defined in 
association with the term ``PM10 emissions.'' See 40 CFR 
51.166(b)(23)(i) and 52.21(b)(23)(i).
    In 1993, under authorization contained in the CAA Amendments of 
1990, EPA adopted increments for PM that were expressed in terms of 
ambient concentrations of PM10, and substituted those 
increments for the original statutory increments for PM based on the 
TSP indicator. See 58 FR 31622, June 3, 1993. As a result, both the 
NAAQS for PM and the PSD increments for PM were henceforth measured by 
the PM10 indicator and, once states revised their SIPs to 
incorporate the new PM10 NAAQS and PM10 
increments, the TSP indicator was no longer considered a regulated 
indicator of particles. However, because the NSPS for PM commonly 
measured performance standard compliance based on emissions of PM using 
the indicator that was roughly associated with the original ambient TSP 
indicator, the EPA stated in the preamble to the 1993 final rule 
promulgating new PSD increments based on PM10 that the 
agency would continue to regulate ``particulate matter emissions'' (25 
tpy significant emissions rate) separately from ``PM10 
emissions'' (15 tpy significant emissions rate) for purposes of PSD 
applicability determinations. Id at 31629.
    Finally, in a final rule issued on May 16, 2008, titled, 
``Implementation of the New Source Review (NSR) Program for Particulate 
Matter Less Than 2.5 Micrometers (PM2.5)'' (73 FR 28321), 
the EPA identified the major source threshold and significant emissions 
rate for PM2.5 to reflect the indicator for the PM NAAQS 
that were issued in 1997. See 40 CFR 51.166(b)(23)(i) and 
52.21(b)(23)(i). Hence, three separate indicators for emissions of PM 
are currently being regulated under the PSD program. Those indicators 
include PM10 and PM2.5, both of which are 
indicators reflecting the way the NAAQS for PM are currently measured, 
and ``particulate matter emissions,'' which is a term that signifies 
the indicator of PM that is measured under various NSPS for PM (40 CFR 
part 60).\8\ All three of the indicators for PM are considered 
separately as regulated NSR pollutants subject to review under the PSD 
program, which means that proposed new and modified sources must treat 
each indicator of PM as a separate pollutant for applicability 
determinations, and must then apply the PSD requirements, as 
appropriate, independently for each indicator of PM.
---------------------------------------------------------------------------

    \8\ In addition to the NSPS for PM, it is noted that states 
regulated ``particulate matter emissions'' for many years in their 
SIPs for PM, and the same indicator has been used as a surrogate for 
determining compliance with certain standards contained in 40 CFR 
part 63, regarding National Emission Standards for Hazardous Air 
Pollutants.
---------------------------------------------------------------------------

    The 2008 final rule also added a provision to the definition 
``regulated NSR pollutant'' in the PSD regulations and the Emission 
Offset Interpretative Ruling that requires the inclusion of the

[[Page 15661]]

condensable fraction of PM for all three indicators of PM. Accordingly, 
the determination of the potential emissions (for permit applicability 
determinations), and the setting of emissions limitations and in-stack 
pollutant measurements (for source compliance purposes) would involve 
the inclusion of the condensable fraction of PM for each of the three 
PM indicators.
    For reasons to be explained, this proposed rulemaking would remove 
``particulate matter emissions'' from that provision defining 
``regulated NSR pollutant'' in the aforementioned regulations, so that 
the relevant provision would require the inclusion of the condensable 
fraction of PM only with regard to emissions of PM10 and 
PM2.5.

IV. Why is EPA proposing to change the definition ``regulated NSR 
pollutant'' with regard to PM?

    When we proposed to amend the PSD rules to address new requirements 
for PM2.5 in 2005, we proposed to revise the definition 
``regulated NSR pollutant'' to add PM2.5 as a regulated 
criteria pollutant and to require that, for purposes of determining PSD 
applicability and setting emissions limitations for a particular 
proposed source or modification, emissions of PM10 and 
PM2.5 included the condensable portion of particulate matter 
that could be emitted by the source or modification. Specifically, the 
proposed regulatory text provided that ``Particulate matter 
(PM10 and PM2.5) emissions include gaseous 
emissions from a source or activity which condense to form particulate 
matter at ambient temperatures.'' See, e.g., 70 FR 65984 at 66067. In 
that text, we had not intended to include the PM indicator referred to 
as ``particulate matter emissions''; instead, we intended the proposed 
text as a ``shorthand'' terminology encompassing both ``PM10 
emissions'' and ``PM2.5 emissions.'' Moreover, we did not 
receive any comments suggesting that the ``PM emissions'' indicator 
should be included in the provision requiring the inclusion of 
condensable PM. Nevertheless, in the final stages of preparing the 2008 
final rule, the proposed text ``Particulate matter (PM10 and 
PM2.5) emissions,'' was revised to read ``Particulate matter 
(PM) emissions, PM10 emissions and PM2.5 
emissions.'' Thus, the inadvertent editorial change made in the final 
rule added ``Particulate matter (PM) emissions'' as a third indicator 
for PM to the sentence for which the PSD regulations would require that 
condensable PM be included.
    The preamble discussion in both the NPRM and the final rulemaking, 
designed to describe the new provision under the definition ``regulated 
NSR pollutant,'' supports the position that our objective was to ensure 
that the condensable PM fraction was included in measurements of 
emissions of PM10 and PM2.5. For example, the 
preamble to the NPRM stated the following: ``The EPA has issued 
guidance clarifying that PM10 includes condensable particles 
and that, where condensable particles are expected to be significant, 
States should use methods that measure condensible emissions.'' 70 FR 
65984 at 66039 (citing a March 31, 1994, EPA memo to the Iowa 
Department of Natural Resources). With regard to PM2.5, we 
stated ``[c]ondensible emissions are essentially fine particles, and 
thus are a larger fraction of PM2.5 emissions than of TSP or 
PM10 emissions.'' Ibid. In the 2008 final rule, we clearly 
stated in the preamble that ``EPA will require that all NSR 
applicability determinations for PM2.5 and PM10 
address condensable emissions as applicable * * *.'' 73 FR 28321 at 
28335.
    We also note that the 2008 final rule added the term ``particulate 
matter (PM) emissions'' to the definition ``regulated NSR pollutant'' 
at 40 CFR part 51 Appendix S (the EPA's ``Emission Offset 
Interpretative Ruling''). This was clearly a mistake because that rule 
pertains to new source review in nonattainment areas (and to sources 
locating outside nonattainment areas that impact air quality in a 
nonattainment area). That being the case, Appendix S is not intended to 
address noncriteria pollutants, since nonattainment areas apply only to 
criteria pollutants. To further illustrate this point, the definition 
``regulated NSR pollutant'' under the nonattainment area NSR 
requirements at 40 CFR 51.165 does not include the term ``particulate 
matter emissions.'' We have already explained that ``particulate matter 
emissions'' refers to the noncriteria indicator for PM subject to 
regulation under various NSPS. Accordingly, EPA is also proposing to 
revise the definition ``regulated NSR pollutant'' under Appendix S to 
remove the term ``particulate matter emissions.'' See proposed 40 CFR 
part 51 Appendix S, Section III.A.31(ii).
    It is important to note that the proposed change would not totally 
exempt the inclusion of the condensable PM fraction as part of 
``particulate matter emissions.'' The proposed revision accounts for 
the fact that, in some cases, the condensable PM fraction should be 
counted. The first case is where the applicable NSPS requires that the 
condensable PM fraction be included in the determination of compliance 
with the performance standard for PM.\9\ The second case is where the 
applicable SIP already requires that the condensable PM fraction be 
included in the measurement of PM. Finally, in the case of any source 
emitting a pollutant that is regulated under section 111 of the Act, 
but is not itself subject to an NSPS, the reviewing authority may 
determine the applicable test method to be used to determine that 
source's compliance.
---------------------------------------------------------------------------

    \9\ In developing the NSPS for Wool Fiberglass Insulation 
Manufacturing facilities (Subpart PPP), the EPA determined that the 
control device could effectively reduce both the solid particles and 
the condensable PM, and promulgated the PM standard based on the 
measurement of both filterable solid particles and condensable PM. 
In addition, the agency established a variant of Method 5, referred 
to as Method 5e, to measure the filterable PM and the total organic 
carbon portion of the impinger catch. See 50 FR 7694, February 25, 
1985.
---------------------------------------------------------------------------

    Thus, we are also proposing to clarify the text contained in the 
definition ``regulated NSR pollutant'' to indicate that for pollutants 
regulated under section 111 of the Act, which includes ``particulate 
matter emissions,'' the applicability of the PSD requirements to that 
pollutant should be determined in a manner consistent with the test 
method prescribed for that particular NSPS or applicable SIP. See 
proposed 40 CFR 51.166(b)(49)(ii) and 52.21(b)(50)(ii). In cases where 
the proposed source or modification of PM is not regulated by any NSPS, 
but is nevertheless required to consider its potential to emit that 
pollutant, we intend to require under the federal PSD requirements at 
40 CFR 52.21 that the applicable measurement will be determined by the 
Administrator. In the case of ``particulate matter emissions,'' we 
generally intend to rely on the common practice of the NSPS to require 
that the applicable measure should be the filterable PM only, based on 
a compliance test method appropriate for such source, e.g., Method 5. 
Under the PSD regulations at 40 CFR 51.166, we propose that states, as 
the reviewing authority, may establish their own policy for applying 
the PSD requirements for ``particulate matter emissions'' to sources 
for which the NSPS does not apply.
    The primary objective of our decision to propose this revision is 
to ensure to the extent practicable that we are not unnecessarily 
imposing a new requirement on state/local agencies and the regulated 
community that has little if any effect on preventing significant air

[[Page 15662]]

quality deterioration or on efforts to attain the primary and secondary 
PM NAAQS. That is, we do not intend to require the inclusion of 
condensable PM in measurements of ``particulate matter emissions'' 
where that has not been a common practice in state and local control 
agencies and there are no ambient standards against which ''particulate 
matter emissions'' are to be compared. Proposed new or modified 
stationary sources of PM typically will be subjected to the PSD 
requirements on the basis of their potential to emit PM10 or 
PM2.5 emissions and will be required to install controls for 
their emissions of PM10 and/or PM2.5, both of 
which must consider the condensable fraction. We also recognize that in 
some cases, some states have chosen to regulate the condensable PM when 
determining the amount of a source's ``particulate matter emissions.'' 
As already explained, the proposed revision would allow states to 
continue that practice by providing the necessary discretion to the 
reviewing authority, but we do not intend to impose such a new PSD 
requirement where it is not otherwise being practiced by the states 
already.

V. Statutory and Executive Order Reviews

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

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

B. Paperwork Reduction Act

    This action does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. 
Burden is defined at 5 CFR 1320.3(b). This proposal only removes the 
requirement to include condensable PM when quantifying ``PM emissions'' 
from proposed new major stationary sources and major modifications 
subject to the PSD program. The proposed change would eliminate a 
requirement that was not intended.

C. Regulatory Flexibility Act

    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 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, which proposes only to remove an unintended requirement 
to include condensable PM when quantifying ``particulate matter 
emissions'' from proposed new major stationary sources and major 
modifications, I certify that this action will not have a significant 
economic impact on a substantial number of small entities. This 
proposed rule will not impose any requirements on small entities 
because small entities are not subject to the requirements of this 
rule.
    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 proposed action contains no federal mandates under the 
provisions of Title II of the Unfunded Mandates Reform Act of 1995 
(UMRA), 2 U.S.C. 1531-1538 for state, local, or tribal governments or 
the private sector. The action would not impose any enforceable duty on 
any state, local or tribal governments or the private sector. This 
action proposes only to remove an unintended requirement to include 
condensable PM when quantifying ``particulate matter emissions'' from 
proposed new major stationary sources and major modifications. Thus, 
this action is not subject to the requirements of sections 202 or 205 
of UMRA.
    This proposed rule is also not subject to the requirements of 
section 203 of UMRA because it does not propose any regulatory 
requirements that might significantly or uniquely affect small 
governments. This action proposes only to remove an unintended 
requirement to include condensable PM when quantifying ``particulate 
matter emissions'' from proposed new major stationary sources and major 
modifications.

E. Executive Order 13132--Federalism

    This proposed rule 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 proposes only 
to remove the unintended requirement to include condensable PM when 
quantifying ``particulate matter emissions'' from proposed new major 
stationary sources and major modification. The requirement was 
inadvertently included in the 2008 final rule for Implementation of the 
PM2.5 NSR Program. Thus, Executive Order 13132 does not 
apply to this rule. Nevertheless, in the spirit of Executive Order 
13132, and consistent with EPA policy to promote communications between 
EPA and state and local governments, EPA plans to specifically solicit 
comment on the proposed rule 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). The proposed 
rule proposes only to remove the requirement to include condensable PM 
when quantifying ``PM emissions'' from proposed new major stationary 
sources and major modification. The requirement was inadvertently 
included in the 2008 final rule for Implementation of the 
PM2.5 NSR Program.
    The Act provides for states to develop plans to regulate emissions 
of air pollutants within their jurisdictions. The Tribal Air Rule (TAR) 
under the Act gives tribes the opportunity to develop and implement Act 
programs to attain and maintain the PM2.5 NAAQS, but leaves 
to the discretion of the tribes the decision of whether to develop 
these programs and which programs, or appropriate elements of a 
program, they will adopt. Thus, Executive Order 13175 does not apply to 
this action.

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

    This proposed action is not subject to Executive Order 13045 (62 FR 
19885, April 23, 1997) because it is not economically significant as 
defined in Executive Order 12866, and because the

[[Page 15663]]

Agency does not believe the environmental health or safety risks 
addressed by this action to eliminate an unintended requirement present 
a disproportionate risk to children. The removal of this requirement 
would not affect one of the basic requirements of the PSD program that 
new and modified major sources must demonstrate that any new emissions 
do not cause or contribute to air quality in violation of the NAAQS.

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. The NTTAA directs EPA to provide 
Congress, through OMB, explanations when the Agency decides not to use 
available and applicable voluntary consensus standards.
    This action does not involve technical standards. Therefore, EPA 
did not consider 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, Feb. 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.
    The EPA has determined that this proposed rule to remove an 
unintended requirement will not have adverse human health or 
environmental effects on minority or low-income populations because it 
does not appreciably affect the level of protection provided to human 
health or the environment.

VI. Statutory Authority

    The statutory authority for this proposed action is provided by 
sections 101, 160, 163, 165, 166, 301, and 307(d) of the Act as amended 
(42 U.S.C. 7401, 7470, 7473, 7475, 7476, 7601, and 7607(d)).

List of Subjects

40 CFR Part 51

    Environmental protection, Administrative practices and procedures, 
Air pollution control, Intergovernmental relations.

40 CFR Part 52

    Environmental protection, Administrative practices and procedures, 
Air pollution control, Intergovernmental relations.

    Dated: March 12, 2012.
Lisa P. Jackson,
Administrator.

    For the reasons stated in the preamble, title 40, chapter I of the 
Code of Federal Regulations is proposed to be amended as follows:

PART 51--[AMENDED]

    1. The authority citation for part 51 continues to read as follows:

    Authority: 23 U.S.C. 101; 42 U.S.C. 7401-7671q.

Subpart I--[Amended]

    2. Section 51.166 is amended by revising paragraphs (b)(49)(i) and 
(ii) and removing (b)(vi) to read as follows:

Sec.  51.166  Prevention of significant deterioration of air quality.

* * * * *
    (b) * * *
    (49) * * *
    (i) Any pollutant for which a national ambient air quality standard 
has been promulgated;
    (a) PM2.5 emissions and PM10 emissions shall 
include gaseous emissions from a source or activity which condense to 
form particulate matter at ambient temperatures. On or after January 1, 
2011, such condensable particulate matter shall be accounted for in 
applicability determinations and in establishing emissions limitations 
for PM2.5 and PM10 in PSD permits. Compliance 
with emissions limitations for PM2.5 and PM10 
issued prior to this date shall not be based on condensable particular 
matter unless required by the terms and conditions of the permit or the 
applicable implementation plan. Applicability determinations made prior 
to this date without accounting for condensable particular matter shall 
not be considered in violation of this section unless the applicable 
implementation plan required condensable particular matter to be 
included;
    (b) Any pollutant identified under this paragraph (b)(49)(i)(b) as 
a constituent or precursor to such pollutant. Precursors identified by 
the Administrator for purposes of NSR are the following:
    (1) Volatile organic compounds and nitrogen oxides are precursors 
to ozone in all attainment and unclassifiable areas.
    (2) Sulfur dioxide is a precursor to PM2.5 in all 
attainment and unclassifiable areas.
    (3) Nitrogen oxides are presumed to be precursors to 
PM2.5 in all attainment and unclassifiable areas, unless the 
State demonstrates to the Administrator's satisfaction or EPA 
demonstrates that emissions of nitrogen oxides from sources in a 
specific area are not a significant contributor to that area's ambient 
PM2.5 concentrations.
    (4) Volatile organic compounds are presumed not to be precursors to 
PM2.5 in any attainment or unclassifiable area, unless the 
State demonstrates to the Administrator's satisfaction or EPA 
demonstrates that emissions of volatile organic compounds from sources 
in a specific area are a significant contributor to that area's ambient 
PM2.5 concentrations.
    (ii) Any pollutant that is subject to any standard promulgated 
under section 111 of the Act, as required to be measured by the 
applicable performance standard for that pollutant. For sources not 
currently regulated by an applicable NSPS, measurement of such 
pollutant shall be determined by the reviewing authority;
* * * * *
    3. Appendix S to Part 51 is amended revising paragraph II.A.31(ii) 
and by removing paragraphs II.A.31(iii) and (iv) to read as follows:

and

Appendix S to Part 51--Emission Offset Interpretative Ruling

* * * * *
    II. * * *
    A. * * *
    31. * * *
    (i) * * *
    (ii) Any pollutant for which a national ambient air quality 
standard has been promulgated;

[[Page 15664]]

    (1) PM2.5 emissions and PM10 emissions 
shall include gaseous emissions from a source or activity, which 
condense to form particulate matter at ambient temperatures. On or 
after January 1, 2011, such condensable particulate matter shall be 
accounted for in applicability determinations and in establishing 
emissions limitations for PM2.5 and PM10 in 
permits issued under this ruling. Compliance with emissions 
limitations for PM2.5 and PM10 issued prior to 
this date shall not be based on condensable particulate matter 
unless required by the terms and conditions of the permit or the 
applicable implementation plan. Applicability determinations made 
prior to this date without accounting for condensable particulate 
matter shall not be considered in violation of this section unless 
the applicable implementation plan required condensable particulate 
matter to be included.
    (2) Any pollutant that is identified under this paragraph 
II.A.31(ii)(2) as a constituent or precursor of a general pollutant 
listed under paragraph II.A.31(i) or (ii) of this Ruling, provided 
that such constituent or precursor pollutant may only be regulated 
under NSR as part of regulation of the general pollutant. Precursors 
identified by the Administrator for purposes of NSR are the 
following:
    (a) Volatile organic compounds and nitrogen oxides are 
precursors to ozone in all ozone nonattainment areas.
    (b) Sulfur dioxide is a precursor to PM2.5 in all 
PM2.5 nonattainment areas.
* * * * *

PART 52--[Amended]

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

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

Subpart A--[Amended]

    5. Section 52.21 is amended by revising paragraphs (b)(50)(i) and 
(ii) and removing paragraph (b)(50)(vi) to read as follows:

and

Sec.  52.21  Prevention of significant deterioration of air quality.

* * * * *
    (b) * * *
    (50) * * *
    (i) Any pollutant for which a national ambient air quality standard 
has been promulgated;
    (a) PM2.5 emissions and PM10 emissions shall 
include gaseous emissions from a source or activity, which condense to 
form particulate matter at ambient temperatures. On or after January 1, 
such condensable particulate matter shall be accounted for in 
applicability determinations and in establishing emissions limitations 
for PM2.5 and PM10 in PSD permits. Compliance 
with emissions limitations for PM2.5 and PM10 
issued prior to this date shall not be based on condensable particular 
matter unless required by the terms and conditions of the permit or the 
applicable implementation plan. Applicability determinations made prior 
to this date without accounting for condensable particular matter shall 
not be considered in violation of this section unless the applicable 
implementation plan required condensable particular matter to be 
included.
    (b) Any pollutant identified under this paragraph (b)(50)(i)(b) as 
a constituent or precursor for such pollutant. Precursors identified by 
the Administrator for purposes of NSR are the following:
    (1) Volatile organic compounds and nitrogen oxides are precursors 
to ozone in all attainment and unclassifiable areas.
    (2) Sulfur dioxide is a precursor to PM2.5 in all 
attainment and unclassifiable areas.
    (3) Nitrogen oxides are presumed to be precursors to 
PM2.5 in all attainment and unclassifiable areas, unless the 
State demonstrates to the Administrator's satisfaction or EPA 
demonstrates that emissions of nitrogen oxides from sources in a 
specific area are not a significant contributor to that area's ambient 
PM2.5 concentrations.
    (4) Volatile organic compounds are presumed not to be precursors to 
PM2.5 in any attainment or unclassifiable area, unless the 
State demonstrates to the Administrator's satisfaction or EPA 
demonstrates that emissions of volatile organic compounds from sources 
in a specific area are a significant contributor to that area's ambient 
PM2.5 concentrations.
    (ii) Any pollutant that is subject to any standard promulgated 
under section 111 of the Act, as required to be measured by the 
applicable performance standard for that pollutant. For sources not 
currently regulated by an applicable NSPS, measurement of such 
pollutant shall be determined by the Administrator;
* * * * *
[FR Doc. 2012-6429 Filed 3-15-12; 8:45 am]
BILLING CODE 6560-50-P
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