2006 National Ambient Air Quality Standards (NAAQS) for Fine Particulate Matter (PM2.5): Designating Nonattainment Areas

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2006 National Ambient Air Quality Standards

(NAAQS) for Fine Particulate Matter (PM2.5):

Designating Nonattainment Areas

(name redacted)

Specialist in Environmental Policy

February 20, 2013

Congressional Research Service

7-....

www.crs.gov

R40096

CRS Report for Congress

Prepared for Members and Committees of Congress

2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Summary

The Environmental Protection Agency (EPA) published revisions to the Clean Air Act (CAA)

National Ambient Air Quality Standards (NAAQS) for particulate matter (particulates, or PM) on

October 17, 2006. EPA’s actions leading up to and following promulgation of the 2006 standard

have been the subject of considerable congressional oversight. EPA and states’ ongoing

implementation of the standard, beginning with the designation of those geographical areas not in

compliance, likewise has been an area of concern and debate among some Members of Congress,

states, and other stakeholders for some time. EPA’s most recent round of periodic review of the

particulates NAAQS and final rule revising the PM NAAQS, published January 15, 2013,

prompted further scrutiny of the ongoing implementation of the standards.

Promulgation of NAAQS sets in motion a process under which the states and EPA identify areas

that exceed the national standard (“nonattainment areas”) using multi-year air quality monitoring

data and other criteria, requiring states to take steps to reduce pollutant concentrations in order to

achieve it. The publication of the final designations for the 2006 NAAQS—and thus the effective

date of the final designations—had initially been delayed pending review by the current

Administration. On November 13, 2009, EPA published its final designations for the 2006 PM

NAAQS that included 120 counties and portions of counties in 18 states as nonattainment areas

based on 2006 through 2008 air quality monitoring data. The final designations, which include

tribal land of 22 tribes, were effective as of December 14, 2009. States have three years from the

effective date to submit nonattainment area State Implementation Plans (SIPs), which identify

specific regulations and emission control requirements that would bring a nonattainment area into

compliance.

The 2006 NAAQS strengthened the pre-existing (1997) standard for “fine” particulate matter 2.5

micrometers or less in diameter (PM2.5) by lowering the allowable daily concentration of PM2.5 in

the air. The daily standard averaged over 24-hour periods was reduced from 65 micrograms per

cubic meter (µg/m3) to 35 µg/m3. However, the annual PM2.5 standard, which addresses human

health effects from chronic exposures to the pollutants, was unchanged from the 1997 standard of

15 µg/m3. The 2006 NAAQS did not substantially modify the daily standard for slightly larger,

but still inhalable, particles less than or equal to 10 micrometers (PM10), retaining the 24-hour

standard but revoking the annual standard for PM10.

EPA’s final nonattainment designations are only for the revised 2006 24-hour PM2.5 standard.

EPA did not require new nonattainment designations for the PM2.5 annual standard and for PM10.

The final designations for the 2006 PM2.5 NAAQS included a few areas designated nonattainment

for PM2.5 for the first time, but, as expected, the majority of the counties identified overlapped

with EPA’s final nonattainment designations for the 1997 PM2.5 NAAQS. EPA’s designations for

the 1997 PM2.5 NAAQS included all or part of 204 counties in 20 states and the District of

Columbia. Most of them were only exceeding the annual standard; only 12 counties were

exceeding both the 24-hour and the annual standards. Thus, the 2006 tightening of the 24-hour

standard resulted in an increased number of areas being designated nonattainment based on

exceedances of both the 24-hour and the annual standards.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Contents

Introduction...................................................................................................................................... 1

EPA’s 2006 Changes to the Particulates NAAQS ............................................................................ 3

Designation of Geographical Nonattainment Areas ........................................................................ 4

NAAQS Designation Process .................................................................................................... 4

2006 PM2.5 24-Hour NAAQS Designations .............................................................................. 6

Comparing the 2006 and 1997 PM2.5 NAAQS Designations .................................................. 10

Demonstrating Attainment with the 2006 PM2.5 NAAQS ............................................................. 14

State Implementation Plans (SIPs) .......................................................................................... 15

Status of Infrastructure SIPs .............................................................................................. 16

National Regulations ............................................................................................................... 17

New Source Review ................................................................................................................ 19

Transportation Conformity ...................................................................................................... 20

Conclusions.................................................................................................................................... 21

Figures

Figure 1. Counties in Nonattainment Only for the 2006 PM2.5 NAAQS 24-Hour Standard

(35 μg/m3): U.S. EPA Final Designations..................................................................................... 8

Figure 2. Counties in Nonattainment for the 1997 PM2.5 NAAQS Annual (15 μg/m3)

and/or 24-Hour (65 μg/m3) Standards: U.S. EPA Final Designations ........................................ 11

Figure 3. Counties in Nonattainment for the Revised PM2.5 NAAQS Annual (15 μg/m3;

Unchanged from 1997) and/or 24-Hour (35 μg/m3; as revised 2006) Standards: U.S.

EPA Final Designations .............................................................................................................. 13

Figure D-1. Counties in Nonattainment for the 24-Hour 2006 PM2.5 NAAQS:

EPA’s Designations as of December 22, 2008 ............................................................................ 37

Tables

Table 1. Counties in Nonattainment for the 1997 PM2.5 NAAQS and in Nonattainment for

the 2006 PM2.5 NAAQS: U.S. EPA Final Designations ............................................................. 12

Table A-1. Schedule for Implementation of the 1997 and the 2006 PM2.5 NAAQS...................... 24

Table B-1. Nonattainment Areas for the 2006 24-Hour PM2.5 NAAQS as Identified by

EPA in the October 8, 2009, Final Designations and in the December 28, 2008,

Status Table, and Nonattainment Designations for the Annual and

24-Hour 1997 PM2.5 NAAQS ..................................................................................................... 25

Table C-1. EPA’s October 8, 2009, Geographic Designations for 2006 PM NAAQS:

Tribes in 24-Hour PM2.5 Nonattainment Areas ........................................................................... 36

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Appendixes

Appendix A. Comparative Time Line for Implementing the 1997 and 2006 PM2.5

NAAQS ...................................................................................................................................... 24

Appendix B. Comparison of EPA’s Final and Interim Nonattainment Designation Areas

for the 2006 24-Hour PM2.5 NAAQS and the Final Nonattainment Designation Areas

for the 1997 PM2.5 NAAQS ........................................................................................................ 25

Appendix C. Tribal Lands: U.S. EPA Designations for the 2006 PM2.5 NAAQS 24-Hour

Standard ...................................................................................................................................... 36

Appendix D. Map Depicting Counties in Nonattainment for the 2006 24-Hour PM2.5

NAAQS: EPA’s Designation as of December 22, 2008 .............................................................. 37

Contacts

Author Contact Information........................................................................................................... 38

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Introduction

Under Sections 108-109 of the Clean Air Act (CAA), Congress mandated that the Environmental

Protection Agency (EPA) set national ambient (outdoor) air quality standards (or NAAQS) for

pollutants whose emissions (1) “may reasonably be anticipated to endanger public health or

welfare”; and (2) “the presence of which in the ambient air results from numerous or diverse

mobile or stationary sources.” The statute further requires that EPA review the latest scientific

studies and either reaffirm or modify previously established NAAQS every five years. EPA has

identified and promulgated NAAQS for six principal pollutants commonly referred to as “criteria

pollutants”: particulate matter (PM), ozone (O3, a key measure of smog), nitrogen dioxide (NO2,

or, inclusively, nitrogen oxides,1 or NOx), sulfur oxides (SOx, or, specifically, SO2), carbon

monoxide (CO), and lead (Pb).

On October 17, 2006, EPA published its revisions to the NAAQS for particulate matter (PM) to

provide protection against potential health effects associated with short- and long-term exposure

to particulates (including chronic respiratory disease and premature mortality).2 The 2006

particulates NAAQS primarily tightened the pre-existing (1997) standard for “fine” particulate

matter 2.5 micrometers or less in diameter (PM2.5).3 The standard for slightly larger, but still

inhalable, particles less than or equal to 10 micrometers (PM10) established in 19874 was not

similarly changed.

Establishing NAAQS does not directly limit emissions; rather, it represents the EPA

Administrator’s formal judgment regarding the level of ambient pollution that will protect public

health with an adequate margin of safety. Promulgation of NAAQS sets in motion a process

under which the states and EPA first identify geographic nonattainment areas, those areas failing

to meet the NAAQS based on monitoring and analysis of relevant air quality data. States then

have three years from the date of EPA’s final designations to submit nonattainment area State

Implementation Plans (SIPs), which identify specific regulations and emission control

requirements that will bring an area into compliance.5 EPA published the final designations for

the 2006 PM2.5 NAAQS on November 13, 2009.6 The final designation rule became effective

December 14, 2009 (30 days from the date of publication). The EPA final designations reflected a

The NAAQS is for NO2; nitrogen gases that are ozone precursors are referred to as NOx.

Federal Register 61143-61233, October 17, 2006. See also EPA’s PM Regulatory Actions website at http://epa.gov/

pm/actions.html.

Federal Register 38652-38896, July 18, 1997. See CRS Report RL32431, Particulate Matter (PM2.5): Implementation

of the 1997 National Ambient Air Quality Standards (NAAQS), by (name redacted).

Federal Register 24634-24715, July 1, 1987.

See EPA’s guidance, “Area Designations for 2006 24-Hour PM2.5 NAAQS - Technical Information,” at

http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

74 Federal Register 58688-58781, November 13, 2009; see also “Area Designations for 2006 24-Hour Fine

Particulate (PM2.5) Standards—Regulatory Actions” at http://www.epa.gov/pmdesignations/2006standards/regs.htm#4.

In a February 3, 2011, final notice, EPA published designations of three areas as “nonattainment” or

“unclassifiable/attainment” for the 2006 24-PM2.5 NAAQS that were deferred in the November 13, 2009, promulgated

designations, 76 Federal Register 6056-6066, http://www.epa.gov/pmdesignations/2006standards/documents/2011-01/

FR-2011-01.pdf. A portion of Pinal County, AZ, was designated nonattainment, eight surrounding counties were

designated unclassifiable/attainment, and Gila River Indian Community and the Ak-Chin Indian community

designations were deferred pending completion of the formal consultation process; Plumas County, CA, and Shasta

County, CA, were designated unclassifiable/attainment (includes surrounding counties).

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change from those announced by the agency in December 22, 2008.7 The publication of final

designations—and thus the effective date of the final designations—had been delayed since

January 2009 pending review by the incoming Administration. EPA initiated review of several

previous agency decisions, including those covered by the White House January 20, 2009,

memorandum,8 and the Office of Management and Budget’s subsequent January 21, 2009,

memorandum,9 on regulatory review.

The 2006 particulates NAAQS generated national interest and debate, and oversight in Congress.

Additionally, several states and industry, agriculture, business, and public advocacy groups

petitioned the U.S. Court of Appeals for the District of Columbia Circuit, challenging certain

aspects of EPA’s 2006 revisions.10 A February 24, 2009, decision11 by the D.C. Circuit granted the

petitions in part, denying other challenges, and remanded the standards to EPA for further

consideration. While the court did not specifically vacate the 2006 PM standards, and their

implementation proceeded, the decision and EPA’s ongoing actions have prompted renewed

interest in PM NAAQS among Members of Congress.12

Simultaneously with the ongoing implementation of the 2006 PM NAAQS, EPA initiated its next

round of statutorily required periodic review of the PM NAAQS not long after the October 2006

promulgation of the standards,13 in part in response to the D.C. Circuit Court’s decision. On

January 15, 2013, EPA published a final rule further revising the PM NAAQS. The January 2013

revisions changed the existing (2006) annual health-based (“primary”) standard for “fine”

particulate matter 2.5 micrometers or less in diameter (or PM2.5), lowering the allowable average

concentration of PM2.5 in the air from the current level of 15 micrograms per cubic meter (µg/m3)

to a limit of 12 µg/m3. The existing primary daily (24-hour) standard for PM2.5 that was reduced

from 65 µg/m3 to 35 µg/m3 in 2006 was retained, as was the existing standard for larger, but still

inhalable, “coarse” particles less than 10 micrometers in diameter, or PM10. “Secondary”

standards that provide protection against “welfare” (non-health) effects, such as ecological effects

and material deterioration, are identical to the primary standards and the same as in 2006. The

See “Area Designations for 2006 24-Hour Fine Particulate (PM2.5) Standards—December 2008 Area Status (Not

Final Designations)” at http://www.epa.gov/pmdesignations/2006standards/documents/2008-12-22/12-08table.htm.

Memorandum to Heads and Acting Heads of Executive Departments and Agencies from Rahm Emanuel, Assistant to

the President and Chief of Staff, regarding Regulatory Review, January 20, 2009, 74 Federal Register 4435, January

26, 2009; the memorandum is also available at http://www.whitehouse.gov/sites/default/files/omb/assets/

information_and_regulatory_affairs/regulatory_review_012009.pdf. Also see Office of Management and Budget

website, “Regulatory Matters,” OIRA Policies and Practices, at http://www.whitehouse.gov/omb/

international_regulatory_cooperation.

Memorandum to Heads and Acting Heads of Executive Departments and Agencies from Peter R. Orszag, Director,

Office of Management and Budget, regarding Implementation of Memorandum Concerning Regulatory Review,

January 21, 2009; see Office of Management and Budget website “Regulatory Matters,” OIRA Policies and Practices,

at http://www.whitehouse.gov/omb/international_regulatory_cooperation.

Cases were consolidated with American Farm Bureau Federation v. U.S. EPA, 2009 Westlaw 437050, No. 06-1410

(D.C. Cir. 2006).

American Farm Bureau Federation v. U.S. EPA, No. 06-1410 (D.C. Cir., February 24, 2009).

For background on the process used to establish the 2006 particulates NAAQS and analysis of associated issues,

including the D.C. Circuit’s February 2009 decision, see CRS CRS Report RL34762, The National Ambient Air Quality

Standards (NAAQS) for Particulate Matter (PM): EPA’s 2006 Revisions and Associated Issues, by (name redacted).

The current review was initiated with EPA’s June 2007 general call for information, U.S. EPA, “Integrated Science

Assessment for Particulate Matter: Call for Information,” 72 Federal Register 35462, June 28, 2007. See also EPA’s

Policy Assessment for the Review of the Particulate Matter National Ambient Air Quality Standards, pp. 1-10 through

1-12, U.S. EPA Office of Air Quality Planning and Standards, Health and Environmental Impacts Division, EPA

452/R-11-003, April 2011, http://www.epa.gov/ttnnaaqs/standards/pm/data/20110419pmpafinal.pdf.

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proposed rule regarding the PM NAAQS published June 29, 2012,14 solicited comments on two

options for a 24-hour PM2.5 standard to improve visibility that were not adopted in the final rule.

For an overview of the revisions to the PM NAAQS published January 15, 2013, see CRS Report

R42934, Air Quality: EPA’s 2013 Changes to the Particulate Matter (PM) Standard, by (name r

edacted).

The following sections of this report focus primarily on the NAAQS implementation process for

designating geographical nonattainment areas with respect to the revisions to the PM2.5 standards

under the 2006 particulates NAAQS, including comparisons with the final designations under the

1997 PM2.5 NAAQS. EPA did not require new nonattainment designations for PM10 based on the

2006 revisions to the standard. Also included is a brief overview of states’ subsequent obligations

for developing and submitting implementation plans (SIPs) for attaining or maintaining

compliance with the NAAQS.

Appendix A contains a comparative time line for implementing the 2006 and 1997 PM2.5

NAAQS. Appendix B provides a state and county breakdown of EPA’s November 13, 2009, final

designated nonattainment areas and areas identified by EPA on December 22, 2008, areas

proposed by the states for the 2006 24-hour PM2.5 NAAQS, as well as the final EPA

nonattainment designations for the 1997 PM2.5 NAAQS. Appendix C identifies tribes included in

EPA’s final nonattainment designations 2006 24-hour PM2.5 NAAQS.

EPA’s 2006 Changes to the Particulates NAAQS

The Clean Air Act (CAA) provides for two types of NAAQS: primary standards, “the attainment

and maintenance of which in the judgment of the [EPA] Administrator ... are requisite to protect

the public health,” with “an adequate margin of safety”; and secondary standards, necessary to

protect public welfare, a broad term that includes visibility impairment as well as damage to

crops, vegetation, property, building materials, etc.15

The primary NAAQS include a daily (24-hour) limit for both PM2.5 and PM10, and an annual

limit for PM2.5 (the previous annual limit for PM10 was revoked). To attain the annual standard,

the three-year average of the weighted annual arithmetic mean PM concentration at each monitor

within an area must not exceed the maximum limit set by the agency. The 24-hour standards are a

concentration-based percentile form, indicating the percentage of the time that a monitoring

station can exceed the standard. For example, a 98th percentile 24-hour standard indicates that a

monitoring station can exceed the standard 2% of the days during the year. For PM2.5 and PM10,

the secondary (welfare) NAAQS are the same as the primary standards.

As modified and published in the October 17, 2006, Federal Register Notice, the primary PM2.5

and PM10 standards are as follows:

For an overview of the proposed revisions to the PM NAAQS published June 29, 2012, see CRS Report R42671, Air

Quality: EPA’s 2012 Proposed Changes to the Particulate Matter (PM) Standard, by (name redacted).

The use of public welfare in the CAA “includes, but is not limited to, effects on soils, water, crops, vegetation,

manmade materials, animals, wildlife, weather, visibility, and climate, damage to and deterioration of property, and

hazards to transportation, as well as effects on economic values and on personal comfort and well-being, whether

caused by transformation, conversion, or combination with other air pollutants” (42 U.S.C. 7602(h)).

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

•

PM2.5: tightened the daily (24-hour) standard, which had allowed no more than

65 micrograms per cubic meter (µg/m3) under the 1997 PM2.5 NAAQS, by setting

a new limit of 35 µg/m3, based on the three-year average of the 98th percentile of

24-hour PM2.5 concentrations; retained the annual standard at 15 µg/m3.

•

PM10: retained the daily standard at 150 µg/m3 set in 1987 but changed from the

99th percentile to no more than one exceedance per year on average over three

years; eliminated the annual maximum concentration (50 µg/m3) standard for

PM10.16

As discussed in more detail in the following section, strengthening the daily (24-hour) standard

for PM2.5 had implications for those counties and partial counties designated nonattainment for

the 1997 PM2.5 NAAQS. With only a few exceptions, most of the designated nonattainment areas

for the 1997 PM2.5 NAAQS were not meeting the annual standard, but were meeting the daily

(24-hour) standard. EPA is not requiring new nonattainment designations for PM10 since the

standards were not strengthened. To the contrary, a number of counties previously designated

nonattainment for PM10 have been determined by EPA to be in attainment since the 2006 revisions

of the particulates NAAQS were promulgated.17

Designation of Geographical Nonattainment Areas

Designating geographical areas not achieving the established NAAQS based on monitoring and

analysis of relevant air quality data is a critical step in NAAQS implementation. Section 107(d) of

the CAA (42 U.S.C. 7407) establishes the process for designating “attainment” and

“nonattainment” areas and setting their boundaries, but allows the EPA Administrator some

discretion in determining what the final boundaries of the areas will be. Areas are identified as

nonattainment when they violate or contribute to the violation of NAAQS.

NAAQS Designation Process

The NAAQS designation process is intended as a cooperative federal-state-tribal18 process in

which states and tribes provide initial designation recommendations to EPA for consideration. In

Section 107(d)(1)(A) (42 U.S.C. 7407), the statute states that the governor of each state shall

submit a list to EPA of all areas in the state, “designating as ... nonattainment, any area that does

not meet (or that contributes to ambient air quality in a nearby area that does not meet) an air

Based on findings in the EPA PM criteria document and staff paper, and the CASAC’s concurrence, that the studies

reviewed do not provide sufficient evidence regarding long-term exposure to warrant continuation of an annual

standard, see 71 Federal Register 2653, Section III. Rationale for Proposed Decision on Primary PM10 Standards,

January 17, 2006.

See “Federal Register Notices Related to Particulate Matter (PM-10) Designations and Classifications” on EPA’s

“Green Book” website, http://www.epa.gov/air/oaqps/greenbk/pfrnrpt4.html#firstnotice. Also see discussion and map

(Figure 1) depicting PM10 nonattainment areas in CRS Report RL34762, The National Ambient Air Quality Standards

(NAAQS) for Particulate Matter (PM): EPA’s 2006 Revisions and Associated Issues, by (name redacted), under the

heading entitled “Rural PM10 Sources.”

Though not required, tribes have been encouraged to submit recommendations. The area designation requirements

under the CAA (§107) are specific with respect to states, but not to tribes. EPA follows the same designation process

for tribes per §§110(o) and 301(d) of the CAA and pursuant to the 1988 Tribal Authority Rule, which specifies that

tribes shall be treated as states in selected cases (40 C.F.R. Part 49). For information regarding tribes that have

participated in the PM2.5 designation recommendation process, see http://www.epa.gov/pmdesignations.

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quality standard” (emphasis added). Areas are identified as “attainment/unclassified”19 when they

meet the standard or when the data are insufficient for determining compliance with the NAAQS.

Following state and tribal designation submissions, the EPA Administrator has discretion to make

modifications, including to the area boundaries. As required by statute (§107(d)1(B)(ii)), the

agency must notify the states and tribes regarding any modifications, allowing them sufficient

opportunity to demonstrate why a proposed modification is inappropriate, but the final

determination rests with EPA.

Measuring and analyzing air quality to determine where NAAQS are not being met is a key step

in determining an area’s designation. Attainment or nonattainment designations are made

primarily on the basis of three years of federally referenced monitoring data.20 EPA began

developing methods for monitoring fine particles at the time the PM2.5 NAAQS were being

finalized in 1997, and operation of the network of monitors for PM2.5 was phased in from 1999

through 2000.

The network of monitors and their locations have been modified over time. In a separate action in

conjunction with the October 2006 publication of the revised particulates NAAQS, EPA amended

its national air quality monitoring requirements, including those for monitoring particle

pollution.21 The amended monitoring requirements were intended to help federal, state, and local

air quality agencies by adopting improvements in monitoring technology. EPA’s final

designations for the 2006 24-hour PM2.5 NAAQS published November 13, 2009, were based on

air quality monitoring data for calendar years 2006 through 2008.

In addition to air emission and air quality data, EPA considers a number of other relevant

factors,22 and recommends that states apply these factors in their determinations in conjunction

with other technical guidance. Examples of these factors include population density and degree of

urbanization (including commercial development), growth rates, traffic and commuting patterns,

weather and transport patterns, and geography/topography. States and tribes may submit

additional information on factors they believe are relevant for EPA to consider.

Nonattainment areas include those counties where pollutant concentrations exceed the standard as

well as those that contribute to exceedance of the standard in adjoining counties. Entire

metropolitan areas tend to be designated nonattainment, even if only one county in the area has

readings worse than the standard. In addition to identifying whether monitored violations are

occurring, states’ or tribes’ boundary recommendations for an area are to also show that violations

are not occurring in those portions of the recommended area that have been excluded, and that

they do not contain emission sources that contribute to the observed violations.

§107(d)(1)(A)(iii) of the CAA provides that any area that EPA cannot designate on the basis of available information

as meeting or not meeting the standards should be designated unclassifiable.

A federally referenced monitor is one that has been accepted for use by EPA for comparison of the NAAQS by

meeting the design specifications and certain precision and bias (performance) specifications (40 C.F.R. Part 58).

Revisions to Ambient Air Monitoring Regulations, final rule, 71 Federal Register 61235-61328, October 17, 2006.

http://www.epa.gov/air/particlepollution/actions.html.

See Chapter 5 of the EPA Technical Support Document for December 17, 2004, final designations for the 1997

PM2.5 NAAQS and April 2005 modifications, for explanations of these factors; available at http://www.epa.gov/

pmdesignations/1997standards/tech.htm.

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2006 PM2.5 24-Hour NAAQS Designations23

On November 13, 2009, EPA published its final designations of 31 areas in 18 states, comprising

120 counties (89 counties and portions of 31 additional counties) for nonattainment of the revised

2006 24-hour PM2.5 standard.24 (See Table B-1 in Appendix B for state-by-state county/area

nonattainment designations.) The counties (and partial counties) that EPA designated as

nonattainment for the 2006 24-hour PM2.5 NAAQS are indicated in the map in Figure 1. The map

distinguishes those counties not previously designated nonattainment for the PM2.5 NAAQS and

those areas that are being designated for the 2006 24-hour PM2.5 24-hour standard, that were

previously designated nonattainment for the 24-hour 1997 PM2.5 NAAQS.

In the February 3, 2011, Federal Register,25 EPA published its final designations of three areas as

“nonattainment” or “unclassifiable/attainment” for the 2006 24-hour PM2.5 NAAQS that were

deferred at the time of the agency’s November 13, 2009, promulgated designations. Designations

were deferred so that EPA could evaluate measurements of high fine particle concentrations by

violating monitors. EPA designated a portion of Pinal County, AZ, as nonattainment. This

designation is not reflected in the map in Figure 1. Eight surrounding counties were designated

unclassifiable/attainment, and Gila River Indian Community and the Ak-Chin Indian community

designations were deferred pending completion of the formal consultation process. Plumas

County, CA, and Shasta County, CA, as well as surrounding counties, were designated

unclassifiable/attainment.

EPA’s November 2009 final designations, which were based on air quality monitoring data for

calendar years 2006 through 2008, do not include counties violating the annual standard, as the

level is unchanged from the 1997 PM2.5 NAAQS. As with the designations for the 1997 PM2.5 and

other criteria pollutant NAAQS standards, several areas include counties from multiple states.

EPA also included portions of tribal lands of 22 tribes in areas designated nonattainment (see

Appendix C for list of tribes included in the final 2006 24-hour PM2.5 NAAQS nonattainment

areas).

EPA’s final designations for the 2006 24-hour PM2.5 standard differed from those identified by the

agency on December 22, 2008, based on air quality monitoring data for calendar years 2005

through 2007. At that time, EPA had identified 58 areas in 25 states, comprising 211 counties

(154 counties and portions of 57 additional counties) for designation as nonattainment of the

revised 2006 24-hour PM2.5 standard26 (see Table B-1 in Appendix B for a comparison of the

state-by-state county/area nonattainment designations; counties (and partial counties) designated

For detailed PM2.5 state/county geographical designation recommendations by EPA and those from individual states

and tribes, for the 1997 and for the 2006 PM2.5 NAAQS, see http://www.epa.gov/pmdesignations.

74 Federal Register 58688-58781, November 13, 2009; see also “Area Designations for 2006 24-Hour Fine

Particulate (PM2.5) Standards—Regulatory Actions” at http://www.epa.gov/pmdesignations/2006standards/regs.htm#4.

76 Federal Register 6056-6066, February 3, 2011, http://www.epa.gov/pmdesignations/2006standards/documents/

2011-01/FR-2011-01.pdf. See also, EPA’s Fact Sheet at http://www.epa.gov/pmdesignations/2006standards/regs.htm.

See EPA’s “Area Designations for 2006 24-Hour Fine Particulate (PM2.5) Standards—December 2008 Area Status

(Not Final Designations),” http://www.epa.gov/pmdesignations/2006standards/documents/2008-12-22/12-08table.htm.

The total number of nonattainment areas and counties includes the three-county (Jefferson, Shelby, and portion of

Walker) area of Birmingham. In the September 20, 2010, Federal Register, EPA announced its determination that a

three-county Alabama nonattainment area (Birmingham) has attaining data for the 2006 24-hour PM2.5 NAAQS (75

Federal Register 57186, September 20, 2010) based on certified ambient air monitoring data showing the area

monitored as in attainment for the 2006 24-hour PM2.5 NAAQS based on 2007-2009 data.

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as nonattainment for the 2006 24-hour PM2.5 NAAQS as of December 22, 2008, are indicated on

the map in Figure D-1 of Appendix D).

Publication of a final designation rule for the 2006 24-hour PM2.5 NAAQS was delayed pending

review by the agency under the current Administration. The review of the final designation rule,

along with several other agency proposed and final actions introduced toward the end of the

previous Administration, was initiated, in part, in response to a White House January 20, 2009,

memorandum,27 and the Office of Management and Budget’s subsequent January 21, 2009,

memorandum,28 regarding regulatory review. During this review, EPA revised its designations

based on more current monitoring data (calendar years 2006-2008).

Delaying publication of the final designation rule resulted in the delay of the expected effective

date, which had been scheduled for April 2009.29 The effective date for the final designation rule

for the 2006 PM NAAQS is December 14, 2009 (30 days from the date of publication).

See footnote 8.

See footnote 9.

See EPA’s guidance, “Area Designations for 2006 24-Hour PM2.5 NAAQS - Technical Information,” at

http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Figure 1. Counties in Nonattainment Only for the 2006 PM2.5 NAAQS 24-Hour Standard (35 μg/m3):

U.S. EPA Final Designations

Source: Prepared by the Congressional Research Service with data obtained from EPA based on EPA’s final designations for the 2006 24-hour

PM2.5 NAAQS. See U.S. EPA, “40 CFR Part 81 Air Quality Designations for the 2006 24-Hour Fine Particle (PM2.5) National Ambient Air Quality

Standards; Final Rule,” 74 Federal Register 58687, November 13, 2009. The map does not reflect EPA’s designation of a portion of Pinal County, AZ,

as nonattainment as published February 3, 2011, 76 Federal Register 6056-6066, February 3, 2011, http://www.epa.gov/pmdesignations/

2006standards/documents/2011-01/FR-2011-01.pdf. Designation of this area had been previously deferred.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

The majority of U.S. counties (including partial counties and tribal lands) were designated

attainment/unclassifiable. While the final number of nonattainment areas and associated counties

can seem small compared with the approximately 3,000 counties throughout the United States,

nonattainment counties tend to have larger populations than those in attainment: for example,

more than 70 million people (more than 20% of the U.S. population)30 live in the 120 counties

designated nonattainment for the 2006 24-hour PM2.5 NAAQS.

The CAA does not specifically require combining neighboring counties within the same

nonattainment area, but it does require the use of metropolitan statistical area boundaries in the

more severely polluted areas (§107(d)(4)(A)(iv)). However, unlike the 1997 PM2.5 standards,

Metropolitan Statistical Areas or Consolidated Metropolitan Statistical Areas31 did not generally

serve as the “presumptive boundary” for nonattainment areas under the 2006 24-hour PM2.5

standards. Rather than establish a presumption for the minimum size of an area, in its June 2007

guidance32 EPA instructed states and tribes to evaluate each area on a case-by-case basis. EPA

expected that nonattainment areas for the 2006 PM2.5 would include counties with monitors

violating the 24-hour standard and nearby counties that contribute to that violation. EPA also

recommended that states and tribes consider using common boundaries for areas to be designated

as nonattainment for both the annual and 24-hour PM2.5 standards. This information in

conjunction with air emission and air quality data, as well other relevant factors as recommended

in EPA’s guidance, such as population density, growth rates, traffic and commuting patterns,

weather and transport patterns, and geography/topography, were used by states in determining the

boundaries for the designated areas.

By December 2007, 20 states provided EPA with recommended nonattainment boundaries for the

2006 revised particulates NAAQS based on 2004 to 2006 monitoring data. The states identified

46 areas comprising 116 counties, including 31 partial counties.33 The state-recommended

designations were primarily based on air quality monitoring data for calendar years 2004 through

2006, criteria and technical guidance from EPA and assistance from its regional offices, and

states’ own relevant information and criteria.

As required by statute, EPA responded to the states with its modifications to the area designation

recommendations for the 2006 PM2.5 NAAQS for the 24-hour standard in letters dated August 19,

2008. The agency identified 57 areas in 26 states, comprising 213 counties (167 counties and

portions of 46 additional counties) for designation as nonattainment for the revised 2006 24-hour

PM2.5 standard. EPA solicited the states’ comments and additional information for consideration

in determining the final designations.34 As it did in implementing the 1997 PM2.5 NAAQS and has

done with other NAAQS, EPA used its discretion to expand the size of nonattainment areas

(added more counties or portions of counties) or to combine areas that a state listed as separate

Three hundred fourteen million in 2012 based on U.S. Census Bureau, “USA Quick Facts”

http://quickfacts.census.gov/qfd/states/00000.html.

As defined by the Office of Management Budget. For more information on metropolitan areas, see

http://www.census.gov/population/metro/.

See EPA’s guidance at “Area Designations for 2006 24-Hour PM2.5 NAAQS - Technical Information,”

http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

For detailed information regarding state recommendations for the 2006 PM2.5 NAAQS, see EPA’s PM Designations

website at http://www.epa.gov/pmdesignations/2006standards/state.htm.

For information regarding EPA’s August 19, 2008, proposed designations and responses to states, see

http://www.epa.gov/pmdesignations/2006standards/regs.htm#2.

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areas into a single larger unit, EPA also combined nonattainment counties across state lines into

the same nonattainment area, if the counties are part of the same metropolitan area.

States (and tribal groups) had 120 days to respond to EPA’s recommendations, and the agency

also issued a notice35 for a 30-day public comment period. As occurred with EPA’s proposed

nonattainment designations for the 1997 PM2.5 NAAQS,36 several states challenged the agency

and maintained support for their original recommendations in response to the agency’s proposed

nonattainment areas for the 2006 24-hour PM2.5 NAAQS. EPA designations for the 2006 24-hour

PM2.5 NAAQS as of December 22, 2008, based on 2005 through 2007 air monitoring data

reflected minor modifications to those proposed; primarily, two counties were removed from the

list of nonattainment areas, and other counties were redefined by designating only specified

locations (“partial”) within the county as nonattainment.37

As discussed previously in this report, the November 13, 2009, final designations for the 2006 24hour PM2.5 NAAQS based on 2006 through 2008 monitoring data resulted in fewer nonattainment

areas/counties than EPA had proposed in August 2008 and identified as of December 2008.

(Table B-1 in Appendix B includes a state-by-state comparison of EPA’s final county/area

nonattainment designations with the agency’s designations as of December 22, 2008.) EPA’s final

designations for the 2006 24-hour PM2.5 NAAQS published in November 2009 included 27 fewer

nonattainment counties than identified as of December 2008, 26 fewer areas than proposed in

August 2008, and 17 fewer areas than recommended by the states. EPA’s final nonattainment

designation areas included 7 fewer states and 91 fewer counties than identified as of December

2008, 7 fewer states and 95 fewer counties than proposed, and 3 fewer states and 27 fewer

counties than recommended by the states.38

Comparing the 2006 and 1997 PM2.5 NAAQS Designations

EPA’s final designations for nonattainment of the 1997 PM2.5 NAAQS (those areas with or

contributing to air quality levels exceeding the annual and 24-hour standards or both) included all

or part of 204 counties in 20 states and the District of Columbia.39 As indicated in the map in

Figure 2, below, the designated nonattainment areas for the 1997 24-hour and annual PM2.5

NAAQS are primarily concentrated in the central, mid-Atlantic, and southeastern states east of

the Mississippi River, as well as in California. More than 2,900 counties in 30 states were

designated attainment/unclassifiable for the 1997 PM2.5 NAAQS.

73 Federal Register 51259-51260, September 2, 2008.

EPA designations for the 1997 PM2.5 NAAQS reflected minor modifications to its proposal; primarily, 19 counties

were removed from the list of nonattainment areas, and other counties were redefined by designating only specified

locations (“partial”) within the county as nonattainment. EPA also subsequently denied six petitions submitted to the

agency requesting reconsideration of the previous designations of one or more full or partial counties as nonattainment

for the 1997 PM2.5 NAAQS. The petitions were for counties in Georgia, Illinois, Michigan, Missouri, Ohio, and West

Virginia; see http://www.epa.gov/pmdesignations/1997standards/regs.htm.

See EPA’s website at http://www.epa.gov/pmdesignations/2006standards/documents/2008-12-22/12-08table.htm,

which provides a table with state-by-state comparisons of designations for the 2006 PM2.5 NAAQS as recommend by

the states, proposed by EPA August 19, 2008, and as identified by EPA December 22, 2008.

See footnote 37.

See EPA’s PM2.5 Designations websites at http://www.epa.gov/pmdesignations and http://www.epa.gov/oar/oaqps/

greenbk/qnca.html. See also CRS Report RL32431, Particulate Matter (PM2.5): Implementation of the 1997 National

Ambient Air Quality Standards (NAAQS), by (name redacted).

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Figure 2. Counties in Nonattainment for the 1997 PM2.5 NAAQS Annual (15 μg/m3)

and/or 24-Hour (65 μg/m3) Standards: U.S. EPA Final Designations

Source: Prepared by the Congressional Research Service based on EPA’s final designations for the 1997 PM2.5 NAAQS, with data obtained from EPA.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Table 1 below illustrates the comparative geographic distribution of counties designated

nonattainment for the 2006 24-hour PM2.5 NAAQS (based on EPA’s final designations as

published in the November 13, 2009, Federal Register), and those counties in EPA’s final area

designations for the annual and 24-hour 1997 PM2.5 NAAQS. Based on the final designations for

the 2006 24-hour PM2.5 NAAQS, 38 counties would be designated nonattainment for PM2.5 for

the first time but the majority of the counties identified overlap with EPA’s final nonattainment

designations for the 1997 PM2.5 NAAQS. Most of the 1997 PM2.5 nonattainment areas were only

exceeding the annual standard; only 12 counties were exceeding both the 24-hour and the annual

standards. Thus, tightening the 24-hour standard resulted in an increased number of areas (82

counties) being designated nonattainment based on exceedances of both the 24-hour and the

annual standard.

Table 1. Counties in Nonattainment for the 1997 PM2.5 NAAQS and in

Nonattainment for the 2006 PM2.5 NAAQS: U.S. EPA Final Designations

PM2.5 NAAQS (annual/24-hour μg/m3)

1997 Standard

15/65 μg/m3

National

West

2006 Standard

15/35 μg/m3

East

National

West

East

Number of counties (including partial counties and D.C.)

Total exceeding the standard

204

191

242

199

Exceeding the 24-hour and annual

standards

Exceeding the 24-hour standard only

Exceeding the annual standard only

192

191

122

121

Source: Prepared by the Congressional Research Service with data compiled from EPA’s websites for PM

designations at http://www.epa.gov/pmdesignations/ and http://www.epa.gov/oar/oaqps/greenbk/qnca.html.

Nonattainment counties are based on EPA’s final designations for the 2006 PM2.5 NAAQS for the 24-hour

standard published November 13, 2009, and the final area designations for the 1997 PM2.5 NAAQS for the 24hour and annual standards as of July 31, 2009.

Note: The counties in the table for the 2006 standards reflect EPA’s final designations for nonattainment area

boundaries for the 2006 24-hour only PM2.5 NAAQS based on 2006-2008 air quality monitoring data, overlaid

with the final designations for the annual standards (which were unchanged) for the 1997 PM2.5 NAAQS as of July

31, 2009.

The map in Figure 3, below, shows the overlap of the final nonattainment designations for the

24-hour standard, as modified under the 2006 24-hour PM2.5 NAAQS, with the final designated

nonattainment areas for the annual standard under the 1997 PM2.5 NAAQS.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

Figure 3. Counties in Nonattainment for the Revised PM2.5 NAAQS Annual (15 μg/m3; Unchanged

from 1997) and/or 24-Hour (35 μg/m3; as revised 2006) Standards: U.S. EPA Final Designations

Source: Prepared by the Congressional Research Service with data obtained from EPA. Nonattainment counties for the 24-hour standard are

based on EPA’s November 13, 2009, final designations for the 2006 24-hour PM2.5 NAAQS; nonattainment counties for the annual standard (which

were unchanged) are based on EPA’s final area designations for the 1997 PM2.5 NAAQS as of December 31, 2008. Partial counties are shown on the

map as whole counties.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

It is difficult to assess what effect the overlap of nonattainment designations may have had on

current control measures in these areas. In some areas, current measures that focused on

achieving attainment for the annual standard may have been sufficient to attain the 24-hour

standard as well. Other areas may have required supplementing current measures or significant

modifications to ensure compliance over a shorter averaging period. The impacts could vary

substantially from area to area within a state and from state to state depending on many factors,

including the type and locations of primary emission sources, current control measures, the extent

to which the area is exceeding the standard, topography, weather, etc.

Once designations take effect, they become an important component of state, local, and tribal

governments’ efforts to reduce fine particle pollution. The designations govern what subsequent

regulatory actions states, tribes, and EPA must take in order to improve or preserve air quality in

each area. These often involve promulgation of new regulations by states, leading to the issuance

of revised air permits, which affect pollution control requirements at various facilities.

Demonstrating Attainment with the

2006 PM2.5 NAAQS

Under the CAA, EPA sets the nationwide standard for criteria pollutants, and EPA and states are

responsible for placing limits on emissions that contribute to criteria pollution and for regulating

entities emitting criteria pollutants. Within three years of issuance of a NAAQS, all states are

required to submit “infrastructure” plans demonstrating that they have the basic air quality

management components necessary to implement the NAAQS.40 Areas designated

attainment/unclassifiable will not have to take steps to improve air quality but under the statute

they must take steps to prevent air quality from deteriorating to unhealthy levels.

For those areas designated nonattainment, state, local, and tribal governments must outline

detailed control requirements in plans demonstrating how they will meet the 2006 PM2.5 NAAQS.

These plans, defined as state implementation plans and referred to as SIPs (TIPs for tribal

implementation plans), were to be submitted to EPA by December 2012, three years after the

effective date of the agency’s final designations of December 14, 2009.41 If states fail to develop

an adequate implementation plan, EPA can impose one. Under CAA, states are required to meet

the 2006 PM2.5 standard “as expeditiously as practicable,” but no later than five years from the

effective date of designation, which would be December 2014, unless an extension allowed under

the CAA is granted.42

§110(a)(2) of the Clean Air Act. For a general overview of the NAAQS implementation plans process, see EPA’s

“State Implementation Plan Overview” at http://www.epa.gov/air/urbanair/sipstatus/overview.html.

§172 of the Clean Air Act. See EPA’s “State Implementation Plan Overview” at http://www.epa.gov/air/urbanair/

sipstatus/overview.html.

Under §172(a)(2)(A) of the CAA, EPA may grant an area an extension of the initial attainment date for one to five

years (in no case later than 10 years after the designation date for the area). A state requesting an extension must submit

an implementation plan (SIP) by the required deadline that includes, among other things, sufficient information

demonstrating that attainment by the initial attainment date is “impracticable.”

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

State Implementation Plans (SIPs)

Within three years of promulgation of a new or revised NAAQS (or shorter period as EPA may

prescribe), Section 110(a)(1) of the CAA requires states to submit revised SIPs that provide for

implementation, maintenance, and enforcement of the new or revised NAAQS. All states are

required to submit SIPs that include the basic program requirements for managing air quality

required in Section 110(a)(2) of the CAA, showing that they have the capacity to attain, maintain,

and enforce the revisions associated with the 2006 PM2.5 NAAQS. These “infrastructure SIP”

submissions must address a number of basic elements, including

•

ambient air quality monitoring and data systems;

•

programs for enforcement of control measures;

•

adequate authority and resources to implement the plan; and

•

prohibition of interstate pollution transport.

Section 110(a)(2)(D)(i) of the act contains four elements that revised SIPs must address. The first

two elements of this section require each state in its SIP to demonstrate adequate provisions for

the ability to prohibit air emissions within the state that (1) contribute significantly to another

state’s nonattainment of the NAAQS, or (2) interfere with another state’s maintenance of the

NAAQS.

Three years from the effective date of the final designations, states and local governments are

required to develop and implement new or revised plans (SIPs) for addressing emissions in those

“nonattainment” areas that do not meet the new or revised NAAQS. Nonattainment area SIPS for

the 2006 PM2.5 NAAQS were required to be submitted to EPA for review and approval by

December 2012. As previously indicated, the effective date of the final designation rule is

December 14, 2009 (30 days from the date of publication). Nonattainment area SIPs include

pollution control measures that will be implemented by federal, state, and local governments, and

rely on models of the impact on air quality of projected emission reductions to demonstrate

attainment. SIPs must identify, among other items, specific regulations, emissions limitations, and

monitoring provisions that will bring an area into compliance.

Several counties designated as nonattainment for the PM2.5 NAAQS were designated for the first

time. As noted earlier, a large portion of the nonattainment areas for the 2006 PM2.5 NAAQS

designated by EPA November 2009, overlap with those areas designated nonattainment for the

1997 PM2.5 NAAQS. However, as discussed in the previous section, these areas were unable to

meet the 2006 revised 24-hour standard, whereas previously many of them were designated

nonattainment based on their inability to meet the annual standard. Exceeding both an annual and

24-hour standard may have implications with respect to existing SIPs, the extent of which could

vary significantly from area to area based on many factors. In some cases SIPs may require

substantial modifications, while in other cases the current SIP may be sufficient to achieve

compliance with both standards.

In a February 2006 advance notice of proposed rulemaking (ANPR)43 outlining an

implementation plan for the transition to the 2006 particulates standards, EPA indicated that it

71 Federal Register 6718, February 9, 2006.

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

would be beneficial for states to consider control strategies that may be useful in attaining the

2006 revised PM2.5 NAAQS when developing their strategies for the 1997 PM2.5 standards.

The basic framework of the implementation rule for the 1997 PM2.5 NAAQS published in April

of 2007 provides guidance for implementation of the 2006 standards.44 The implementation rule

describes the requirements that states and tribes must meet in their implementation plans to

achieve and maintain attainment. The rule also provides guidance and procedures for establishing

controls to achieve and maintain attainment. The implementation rule also includes guidance for

submitting a SIP when reaching attainment within the five-year requirement is impractical. The

implementation rule takes into account existing (oftentimes pending) federal regulations that

contribute to controlling criteria pollutants and their precursors.45 In addition to the 2007

implementation rule for the 1997 PM2.5 NAAQS, EPA outlined implementation guidance

regarding the development of SIPs to demonstrate attainment with the 2006 PM2.5 NAAQS in a

March 12, 2012, memorandum to EPA Regional Air Directors.46

Status of Infrastructure SIPs

On June 9, 2010, EPA published a finding that 23 states, the District of Columbia, and 5

territories had failed to submit “infrastructure” SIPs to address the requirements of CAA Section

110(a)(2)(D)(i)(I) with respect to the 2006 PM2.5 NAAQS.47 On July 20, 2011, EPA published a

notice finding that one additional state had failed to submit a SIP to address those

requirements.48 Both of EPA’s findings notices49 addressed the first two of four elements under

Section 110(a)(2)(D)(i) to satisfy interstate transport requirements. In an August 8, 2011, Federal

(CSAPR) which were to address the emissions from 28 states that significantly affect downwind

states’ ability to attain and maintain compliance with the 2006 (and 1997) PM2.5 NAAQS (as well

as the 1997 ozone NAAQS).50,51 These FIPs limited emissions through the regulation of electric

EPA published its final implementation rule for the 1997 PM2.5 NAAQS on April 25, 2007. The rule addresses

attainment demonstration and modeling; local emission reduction measures, including reasonably available control

technology (RACT), reasonably available control measures (RACM), and reasonable further progress (RFP); regional

emission reduction strategies; innovative program guidance; emission inventory requirements; transportation

conformity; and stationary source test methods (72 Federal Register 20586-20667, April 25, 2007).

The term precursor refers to a directly emitted pollutant that, when released to the atmosphere, forms, or contributes

to the formation of, a secondary pollutant for which an ambient air quality standard has been adopted.

March 12, 2012, Memorandum from Stephen D. Page, Director, Office of Air Quality Planning and Standards, to

EPA Regional Air Directors (Regions I-X), “Implementation Guidance for the 2006 24-Hour Fine Particle (PM2.5)

National Ambient Air Quality Standards (NAAQS),” http://www.epa.gov/ttn/naaqs/pm/pdfs/

20120302_implement_guidance_24-hr_pm2.5_naaqs.pdf.

U.S. EPA, “Finding of Failure To Submit Section 110 State Implementation Plans for Interstate Transport for the

2006 National Ambient Air Quality Standards for Fine Particulate Matter,” 75 Federal Register 32673-32676, June 9,

2010. See also EPA’s Fact Sheet at http://www.epa.gov/air/particlepollution/actions.html.

U.S. EPA, “Finding of Failure To Submit Section 110 State Implementation Plans for Interstate Transport for the

2006 National Ambient Air Quality Standards for Fine Particulate Matter,” 76 Federal Register 43180-43183, July 20,

2011. See also EPA’s Fact Sheet at http://www.epa.gov/air/particlepollution/actions.html.

Under the CAA, the EPA findings notice initiates a two-year deadline for the agency to promulgate a Federal

Implementation Plan (FIP) unless a state submits, and EPA approves, a plan to meet these two elements prior to the

deadline.

U.S. EPA, “Federal Implementation Plans: Interstate Transport of Fine Particulate Matter and Ozone and Correction

of SIP Approvals, 76 Federal Register 48208-48483, August 8, 2011, http://www.gpo.gov/fdsys/pkg/FR-2011-08-08/

pdf/2011-17600.pdf. In the Notice, EPA also modified its prior approvals of certain SIPs, rescinding statements that the

(continued...)

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2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

generating units. Eleven states identified in the findings notices were included in EPA’s CSAPR.

On August 21, 2012, the U.S. Court of Appeals for the District of Columbia issued a 2-1 decision

to vacate and remand the CSAPR.52 On October 5, 2012, the U.S. Department of Justice filed a

petition53 seeking en banc rehearing of the D.C. Circuit’s August 21, 2012, decision regarding the

CSAPR. The D.C. Circuit denied requests for both a panel and for the en banc rehearing on

January 24, 2013.54

In a separate Notice published September 8, 2011, EPA notified six states, the District of

Columbia, and the Commonwealth of Puerto Rico that they failed to submit complete

infrastructure SIPs that include required elements to ensure the implementation of the 2006 24hour PM2.5 NAAQS.55 In some cases the submission was missing only one or two elements, while

others were missing multiple elements.56

At the time this report was updated, EPA had approved, or approved portions of, submissions

from a number of states. In most cases the elements not approved were with regard to interstate

requirements.

National Regulations

EPA anticipated that in many cases emission reductions from implementing national regulations

and strategies would provide a framework for helping states achieve attainment with the PM2.5

NAAQS. These national actions include the

•

Cross-State Air Pollution Rule (CSAPR);57

•

Mercury and Air Toxics Standards (MATS);58

•

Light-Duty Vehicle Tier 2 Rule;59

(...continued)

submitted SIPs satisfy the interstate transport FIPs with respect to the 1997 PM2.5 NAAQS (and the 1997 ozone

NAAQS) for 22 states.

U.S. EPA, “Federal Implementation Plans for Iowa, Michigan, Missouri, Oklahoma, and Wisconsin and

Determination for Kansas Regarding Interstate Transport of Ozone,” 76 Federal Register 80760-80777 December 27,

2011.

EME Homer City Generation, L.P. v. Environmental Protection Agency, D.C. Cir., No. 11-1302, August 21, 2012,

http://www.cadc.uscourts.gov/internet/opinions.nsf/19346B280C78405C85257A61004DC0E5/$file/11-13021390314.pdf. See also U.S. EPA’s website, “Cross-State Air Pollution Rule (CSAPR),” http://epa.gov/crossstaterule/

for this decision and other related documents.

http://epa.gov/crossstaterule/pdfs/Rehearing_Petition_617874.pdf. For status of the petition see EPA website “CrossState Air Pollution Rule (CSAPR)” http://epa.gov/crossstaterule/.

EME Homer City Generation, L.P. v. Environmental Protection Agency, D.C. Cir., No. 11-1302, January 24, 2013

Orders. See U.S. EPA’s website, “Cross-State Air Pollution Rule (CSAPR),” http://epa.gov/crossstaterule/.

U.S. EPA, “Findings of Failure to Submit a Complete State Implementation Plan for Section 110(a) Pertaining to the

2006 Fine Particulate Matter (PM2.5 ) NAAQS, 76 Federal Register 55577-55581, September 8, 2011.

See the table summarizing the missing elements for each of the six states, District of Columbia, and Puerto Rico

presented in EPA’s Fact Sheet, available at http://www.epa.gov/air/particlepollution/actions.html.

76 Federal Register 48208-48483, August 8, 2011.

77 Federal Register 9304-9513, February 16, 2012.

65 Federal Register 6822-6870, February 10, 2000.

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•

Heavy Duty Diesel Rule;60

•

Clean Air Nonroad Diesel Rule;61

•

Regional Haze Regulations and Guidelines for Best Available Retrofit

Technology Determinations;62

•

NOx Emission Standard for New Commercial Aircraft Engines;63

•

Emissions Standards for Locomotives and Marine Compression-Ignition

Engines;64

•

Emission Standards Ignition Engines, Control of Emissions for Nonroad Spark

Ignition Engines and Equipment;65

•

Category 3 Oceangoing Vessels;66

•

Reciprocating Internal Combustion Engines (RICE) National Emissions

Standards for Hazardous Air Pollutants (NESHAPS);67 and

•

New Source Performance Standards and Emissions Guidelines for

Hospital/Medical/Infectious Waste Incinerators Final Rule Amendments.68

Stakeholders and some Members of Congress have been skeptical about EPA’s expectations with

respect to the corollary benefits associated with some of these regulations, and have raised

concerns about pending efforts to delay some of the more recent programs and historical delays

of others. For example, one of the key federal regulations that was designed to control emissions

of air pollution that causes air quality problems in downwind states, EPA’s May 2005 Clean Air

Interstate Rule (CAIR),69 was vacated in a July 11, 2008, decision (North Carolina v. EPA), by the

U.S. Court of Appeals for the D.C. Circuit.70 The D.C. Circuit subsequently modified its decision

on December 23, 2008,71 in response to an EPA motion,72 reversing its decision to vacate CAIR

while EPA developed a replacement rule. As discussed in the previous section of this report, the

65 Federal Register 59896-59978, October 6, 2000.

69 Federal Register 38958-39273, January 29, 2004.

70 Federal Register 39104-39172, July 6, 2005.

70 Federal Register 69644-69687, November 17, 2005.

73 Federal Register 37095-37144, republished June 30, 2008.

73 Federal Register 59034-59380, October 8, 2008.

75 Federal Register 22896-23065, April 30, 2010.

75 Federal Register 51570-51608, August 20, 2010; Proposed Amendments 77 Federal Register 33812-33857, June

7, 2012.

74 Federal Register 51368-51415, October 6, 2009.

Promulgated under the CAA, 42 U.S.C. 7401 et seq., see U.S. EPA, “Ambient air quality standards, national—Fine

particulate matter and ozone; interstate transport control measures,” 70 Federal Register 25162, May 12, 2005.

North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008); see CRS Report RL34589, Clean Air After the CAIR

Decision: Multi-Pollutant Approaches to Controlling Powerplant Emissions, by (name redacted), (name redacted), and

(name redacted); also see EPA’s Clean Air Interstate le

Ruwebsite at http://www.epa.gov/CAIR/index.html.

550 F.3d 1176 (D.C. Cir. 2008).

EPA requested reconsideration on September 24, 2008, with suggestion for rehearing by the entire court.

Alternatively, EPA requested that the CAIR rule be allowed to continue in effect while the agency developed a

replacement program that satisfied the court’s July 2008 decision. The Natural Resources Defense Council (NRDC),

the National Mining Association, and the Utility Air Regulatory Group also petitioned the court for a rehearing.

Congressional Research Service

2006 Fine Particulate Matter (PM2.5) NAAQS Nonattainment Designations

subsequent replacement rule, the Cross-State Air Pollution Rule (“Cross-State Rule” or

CSAPR),73 was to have gone into effect in 2012 but was stayed in December 2011, then vacated

on August 21, 2012, by the D.C. Circuit Court of Appeals.74 The U.S. Department of Justice filed

a petition75 on October 5, 2012, seeking en banc rehearing of the D.C. Circuit’s August 21, 2012,

decision regarding the CSAPR, which was subsequently denied by the D.C. Circuit on January

24, 2013.

Additionally, EPA itself has stayed the Mercury and Air Toxics Standards (MATS), pending

reconsideration. Other remanded rules include the hazardous air pollutant (“MACT”) standards

for boilers and cement kilns. EPA has delayed implementation of the boiler MACT rules for more

than a year and a half while considering changes to the requirements. The agency has also

extended the compliance deadline for the cement kiln MACT by two years.

These actions have had a disruptive effect on certain aspects of the implementation of the 2006

revised PM2.5 NAAQS.

New Source Review76

Designated nonattainment areas also are subject to new source review (NSR) requirements.

Enacted as part of the 1977 CAA Amendments and modified in the 1990 CAA Amendments,

NSR is designed to ensure that newly constructed facilities, or substantially modified existing

facilities, do not result in violation of applicable air quality standards. NSR provisions outline

permitting requirements both for construction of new major pollution sources and for

modifications to existing major pollution sources. The specific NSR requirements for affected

sources depend on whether the sources are subject to “Prevention of Significant Deterioration”

(PSD) or nonattainment provisions.77

EPA promulgated a rule in May 200878 that contained several NSR program requirements for

sources that emit PM2.5 and the pollutants that contribute to its formation (precursors), including

SIPS modifications to state NSR programs to account for emissions of PM2.5. On October 20,

2010, EPA published a final rule amending requirements under the Clean Air Act PSD program

See U.S. EPA, “Federal Implementation Plans: Interstate Transport of Fine Particulate Matter and Ozone and

Correction of SIP Approvals,” 76 Federal Register 48208-48483, August 8, 2011, http://www.gpo.gov/fdsys/pkg/FR2011-08-08/pdf/2011-17600.pdf. Explanatory and background material can be found on EPA’s website at

http://www.epa.gov/crossstaterule/actions.html.

EME Homer City Generation, L.P. v. Environmental Protection Agency, D.C. Cir., No. 11-1302, August 21, 2012,.

http://www.cadc.uscourts.gov/internet/opinions.nsf/19346B280C78405C85257A61004DC0E5/$file/11-13021390314.pdf. See also U.S. EPA’s website “Cross-State Air Pollution Rule (CSAPR)” for this decision and other