Clean Air Issues in the 113th Congress:
An Overview
James E. McCarthy
Specialist in Environmental Policy
March 22, 2013
Congressional Research Service
7-5700
www.crs.gov
R42895
CRS Report for Congress
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epared for Members and Committees of Congress
Clean Air Issues in the 113th Congress: An Overview
Summary
Oversight of EPA regulatory actions is expected to be the main focus of interest as the 113th
Congress considers air quality issues.
Air quality has improved substantially in the United States in the 40 years of the Environmental
Protection Agency’s Clean Air Act regulation. According to the agency’s science advisers and
others, however, more needs to be done to protect public health and the environment from the
effects of air pollution. Thus, the agency continues to promulgate regulations using authority
given it by Congress in amendments to the Clean Air Act more than 20 years ago. Members of
Congress from both parties have raised questions about the cost-effectiveness of some of these
regulations and/or whether the agency has exceeded its statutory authority in promulgating them.
Others in Congress have supported EPA, noting that the Clean Air Act, often affirmed in court
decisions, has authorized or required the agency’s actions.
EPA’s regulatory actions on greenhouse gas (GHG) emissions have been one focus of
congressional interest. Although the Obama Administration has consistently said that it would
prefer that Congress pass new legislation to address climate change, such legislation now appears
unlikely. Instead, over the last four years, EPA has developed GHG emission standards using its
existing Clean Air Act authority. Relying on a finding that GHGs endanger public health and
welfare, the agency promulgated GHG emission standards for cars and light trucks on May 7,
2010, and again on October 15, 2012, and for larger trucks on September 15, 2011. The
implementation of these standards, in turn, triggered permitting and Best Available Control
Technology requirements for new major stationary sources of GHGs (power plants,
manufacturing facilities, etc.).
It is the triggering of standards for stationary sources that has raised the most concern in
Congress: legislation has been considered in both the House and Senate aimed at preventing EPA
from implementing these requirements. The House passed several of these bills in the 112th
Congress, but none of them passed the Senate.
Besides addressing climate change, EPA has taken action on a number of other air pollution
regulations, generally in response to court actions remanding previous rules. Remanded rules
included the Clean Air Interstate Rule (CAIR) and the Clean Air Mercury Rule—rules designed
to control the long-range transport of sulfur dioxide, nitrogen oxides, and mercury from power
plants through cap-and-trade programs. Other remanded rules include hazardous air pollutant
standards for boilers and cement kilns (standards referred to as “MACT” standards). EPA has
addressed the court remands through new regulations, but many in Congress view these
regulations as overly stringent. In the 112th Congress, the House passed four bills (H.R. 2250,
H.R. 2401, H.R. 2681, and H.R. 3409) to delay or revoke the new standards and change the
statutory requirements for their replacements. None of these passed the Senate, however.
In addition to these rules, EPA is also reviewing ambient air quality standards (NAAQS) for
ozone and other widespread air pollutants. These standards serve as EPA’s definition of clean air,
and drive a range of regulatory controls. The revised NAAQS and EPA’s review process have also
faced opposition in Congress. As passed by the House in the 112th Congress, H.R. 2401 and H.R.
3409 would have amended the Clean Air Act to require EPA to consider feasibility and cost in
setting NAAQS, reversing a unanimous 2001 Supreme Court decision that the law requires
standards based on health considerations alone. The Senate did not pass either measure.
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Clean Air Issues in the 113th Congress: An Overview
Contents
Introduction ...................................................................................................................................... 1
EPA’s Greenhouse Gas Regulations ................................................................................................. 1
Emissions from Power Plants .......................................................................................................... 3
Cross-State Air Pollution / Clean Air Interstate Rule (CAIR) ................................................... 4
North Carolina v. EPA ......................................................................................................... 4
EPA’s CAIR Replacement: The Cross-State Air Pollution Rule ......................................... 5
Legislative and Judicial Options ......................................................................................... 6
Mercury and Air Toxics Standards ............................................................................................ 7
Background ......................................................................................................................... 7
New Jersey v. EPA ............................................................................................................... 8
Other Mercury / Air Toxics Issues....................................................................................... 8
The Utility MACT / Mercury and Air Toxics Standards ..................................................... 9
Legislative and Judicial Action ......................................................................................... 10
Cumulative Impacts of EPA Rules .......................................................................................... 11
Air Quality Standards .................................................................................................................... 12
Background.............................................................................................................................. 13
Ozone and PM NAAQS Reviews ............................................................................................ 14
Ozone ................................................................................................................................ 14
Particulate Matter (Including “Farm Dust”) ...................................................................... 15
Other Issues ................................................................................................................................... 16
Contacts
Author Contact Information........................................................................................................... 17
Congressional Research Service
Clean Air Issues in the 113th Congress: An Overview
Introduction
With the 113th Congress divided like the 112th into a Republican-controlled House and a majority-
Democratic Senate, and the President having been re-elected, environmental issues, including
those related to air quality, may reflect those of the last two years. In that period, interest in air
quality issues was dominated by efforts to prevent the Environmental Protection Agency (EPA)
from promulgating and implementing new emission control requirements. Often under court
order, EPA has used authorities Congress gave it in the Clean Air Act amendments of 1970, 1977,
and 1990 to address longstanding issues posed by emissions from various sources. EPA’s
regulations on greenhouse gas emissions from both mobile and stationary sources and on
conventional and hazardous air pollutants emitted by electric power plants, cement kilns, and
boilers have been of particular interest, as have the agency’s efforts to revise ambient air quality
standards for ozone and particulate matter. These issues remain in the 113th Congress; particularly
in the House, efforts to restrain agency regulatory actions are expected to occupy a prominent
place.
EPA’s Greenhouse Gas Regulations
A continuing focus of congressional interest has been EPA regulatory actions to limit greenhouse
gas (GHG) emissions using existing Clean Air Act authority. EPA actions have focused on six
gases or groups of gases that multiple scientific studies have linked to climate change.1 Of the six
gases, carbon dioxide (CO2 ), produced by combustion of fossil fuels, is by far the most prevalent,
accounting for nearly 85% of annual emissions of the combined group when measured as CO2
equivalents.
Members from both sides of the aisle, including a majority of the House in the 112th Congress,
have expressed concerns about EPA proceeding with GHG regulations that could have major
economic impacts. Some argue that the case for GHG controls has not been proven. Others
maintain that EPA should delay taking such action until Congress more explicitly authorizes it.
EPA, by contrast, concludes that the Clean Air Act already requires action: a 2007 Supreme Court
decision interpreting EPA’s Clean Air Act authority, Massachusetts v. EPA,2 found that the agency
must weigh whether GHG emissions endanger public health and welfare and, if it concludes that
they do, proceed with regulation. The agency made this endangerment finding in December
2009,3 and proceeded to promulgate GHG emission standards for new 2012-2016 cars and light
trucks, May 7, 2010.4 The implementation of the standards for motor vehicles led to permitting
requirements and the imposition of Best Available Control Technology for new major stationary
1 The six are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), sulfur hexafluoride (SF6), hydrofluorocarbons
(HFCs), and perfluorocarbons (PFCs).
2 549 U.S. 497 (2007).
3 74 Federal Register 66496. While generally referred to as the “endangerment finding” (singular), the Federal
Register notice consists of two separate findings: a Finding That Emissions of Greenhouse Gases Endanger Public
Health and Welfare, and a Finding That Greenhouse Gases from Motor Vehicles Cause or Contribute to the
Endangerment of Public Health and Welfare.
4 75 Federal Register 25324. For additional information, including a link to the standards, see http://www.epa.gov/otaq/
climate/regulations.htm#finalR. The agency subsequently (on October 15, 2012) promulgated GHG standards for
model years 2017-2025.
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sources of GHGs beginning January 2, 2011. (For information on these regulations and permit
requirements, see CRS Report R40506, Cars, Trucks, and Climate: EPA Regulation of
Greenhouse Gases from Mobile Sources, and CRS Report R41212, EPA Regulation of
Greenhouse Gases: Congressional Responses and Options.)
The prospect of GHG standards for motor vehicles has not been particularly controversial. In
May 2009, President Obama reached agreement with major U.S. and foreign auto manufacturers
and other stakeholders regarding the substance of GHG emission and related fuel economy
standards.5 The auto industry supported a national agreement, in part, to avoid having to meet
standards on a state-by-state basis; thus, it has not supported efforts to block EPA’s motor vehicle
GHG standards. A second round of standards, promulgated in October 2012,6 was also preceded
by an agreement with the auto industry and key stakeholders. (For additional details, see CRS
Report R42721, Automobile and Truck Fuel Economy (CAFE) and Greenhouse Gas Standards.)
EPA and the National Highway Traffic Safety Administration (NHTSA) have also promulgated
joint GHG emission and fuel economy standards for medium- and heavy-duty trucks,7 which
have been supported by the affected industries. (For a brief summary of these, see CRS Report
R41563, Clean Air Issues in the 112th Congress.)
The decisions to move forward on GHG standards for new motor vehicles were seen by many,
including EPA, as precedents for other potential standards. On December 23, 2010, the agency
announced that it had reached a settlement agreement with 11 states, the City of New York, the
District of Columbia, and 3 environmental groups under which it would propose GHG emission
standards for power plants by July 26, 2011, and for refineries by December 10, 2011, with
promulgation by May 2012 and November 2012 respectively. EPA proposed standards for new
power plants on April 12, 2012, but other than that, the agency has not yet taken the agreed upon
actions.
The adoption of motor vehicle GHG standards has triggered GHG permit requirements for new
stationary sources, however. Section 165 of the Clean Air Act requires preconstruction permits
and the imposition of best available control technology for new major sources of all pollutants
“subject to regulation” under the act. When the GHG standards for motor vehicles took effect,
GHGs became subject to regulation, triggering Section 165. The GHG permit requirements took
effect January 2, 2011.
5 GHG emissions and fuel economy are directly related, because 94% of GHG emissions from light duty vehicles are
the result of fuel combustion. The less fuel a vehicle uses, the lower will be its GHG emissions.
The President’s announcement and related documents, including a Notice of Upcoming Joint Rulemaking to Establish
Vehicle GHG Emissions and CAFE Standards, which appeared in the May 22, 2009, Federal Register, and both the
draft and final emission standards can be found at http://www.epa.gov/otaq/climate/regulations.htm. For additional
information, see CRS Report R42721, Automobile and Truck Fuel Economy (CAFE) and Greenhouse Gas Standards,
by Brent D. Yacobucci, Bill Canis, and Richard K. Lattanzio, or CRS Report R40506, Cars, Trucks, and Climate: EPA
Regulation of Greenhouse Gases from Mobile Sources.
6 http://www.epa.gov/otaq/climate/regs-light-duty.htm#new1.
7 U.S. Environmental Protection Agency, U.S. Department of Transportation, “Greenhouse Gas Emissions Standards
and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles; Final Rules,” 76 Federal Register
57106, September 15, 2011.
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EPA has focused its initial permitting efforts on the largest emitters, granting smaller sources at
least a six-year reprieve; nevertheless, this triggering of standards for stationary sources (power
plants, manufacturing facilities, and others) has raised substantial concern in Congress.
Legislation introduced in the 112th Congress aimed to prevent EPA from implementing GHG
emission requirements. More than a dozen bills were introduced, as well as amendments and
riders on appropriations bills. The House passed three of these bills, but the Senate did not follow
suit. (For additional detail, see CRS Report R41563, Clean Air Issues in the 112th Congress.)
EPA will continue to implement GHG emission standards in 2013; thus, legislation to restrict
EPA’s authority with respect to GHG emissions is considered likely to be considered again in the
113th Congress.
Emissions from Power Plants
Issues related to emissions from electric power plants—principally sulfur dioxide (SO2), nitrogen
oxides (NOx), and mercury—will likely be another focus of interest in the 113th Congress. Bush
Administration regulations addressing these emissions were vacated by the D.C. Circuit Court of
Appeals in two 2008 decisions (North Carolina v. EPA and New Jersey v. EPA). As a result, EPA
has developed new regulations to address the court’s concerns. It promulgated regulations
addressing SO2 and NOx on August 8, 2011, and for power plant emissions of mercury and other
hazardous air pollutants on February 16, 2012.
Coal-fired power plants are among the largest sources of air pollution in the United States. In
2005, they accounted for 10.2 million tons of sulfur dioxide (SO2) emissions (70% of the U.S.
total), 52 tons of mercury emissions (46% of the U.S. total), and 3.6 million tons of nitrogen
oxides (19% of the U.S. total). Power plants are considered major sources of fine particles
(PM2.5), many of which form in the atmosphere from emissions from a wide range of stationary
and mobile sources. In addition, they account for about 40% of U.S. anthropogenic emissions of
the greenhouse gas carbon dioxide.
Under the Clean Air Act, however, the plants have not necessarily been subject to stringent
requirements: emissions and the required control equipment can vary depending on the location
of the plant, when it was constructed, whether it has undergone major modifications, the specific
type of fuel it burns, and, to some extent, the vagaries of state and EPA enforcement policies.
More than half a dozen separate Clean Air Act programs could potentially be used to control
emissions, which makes compliance strategy complicated for utilities and difficult for regulators.
Because the cost of the most stringent available controls, for the entire industry, could range into
the tens of billions of dollars, utilities have fought hard and rather successfully to limit or delay
regulations affecting them, particularly with respect to plants constructed before the Clean Air Act
of 1970 was passed. This group, which includes about one-third of coal-fired capacity, are
generally referred to as “grandfathered” plants.
As discussed below under “Air Quality Standards,” new ambient air quality standards for ozone,
fine particles, and SO2 will be taking effect in the next few years. Emissions of NOx and SO2 will
have to be reduced to meet these standards. (NOx contributes to the formation of ozone and fine
particles; SO2, besides being a regulated pollutant in its own right, is among the sources of fine
particles.)
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The continuing controversy over the interpretation of New Source Review requirements for
existing power plants (which require the installation of Best Available Control Technology
whenever an existing power plant undergoes major modifications) has exerted pressure for a
more predictable regulatory structure, as well.
Thus, some in industry, environmental groups, Congress, and the last three Administrations have
said that legislation addressing power plant pollution in a comprehensive (multi-pollutant)
fashion would be desirable. Such legislation would address the major pollutants on a coordinated
schedule and would rely, to a large extent, on a system such as the one used in the acid rain
program, where national or regional caps on emissions are implemented through a system of
tradable allowances. The key questions have been how stringent the caps should be and whether
carbon dioxide (CO2), the major gas of concern with regard to climate change, would be among
the emissions subject to a cap. The Senate Environment and Public Works Committee has voted
twice on a multi-pollutant bill (in 2002 and 2005), but neither of the bills progressed to the Senate
floor. In the House, similar bills were introduced, but none progressed to markup.
Cross-State Air Pollution / Clean Air Interstate Rule (CAIR)
Unable to obtain congressional approval of its multi-pollutant bill (the “Clear Skies” bill), the
Bush Administration’s EPA announced on March 10, 2005, that it would use existing Clean Air
Act authority to promulgate final regulations similar to those in the bill for utility emissions of
SO2 and NOx in 27 eastern states and the District of Columbia.8
The Clean Air Interstate Rule (CAIR) established cap-and-trade provisions for SO2 and NOx. A
separate regulation, the Clean Air Mercury Rule (CAMR), promulgated at the same time,
established a cap-and-trade system for mercury emissions.9 CAIR covered only the eastern half of
the country, but since most of the grandfathered generation capacity is located there (in the East,
Midwest, and South), EPA projected that nationwide emissions of SO2 would decline 53% by
2015 and NOx emissions 56%, as compared to nationwide emissions in 2001. The agency also
projected that the rule would result in $85 billion-$100 billion in health benefits annually by
2015, including the annual prevention of 17,000 premature deaths. CAIR’s health and
environmental benefits would be more than 25 times greater than its costs, according to EPA.10
North Carolina v. EPA
CAIR was one of the few Bush Administration environmental initiatives that was generally
supported by environmentalists. It also had broad support in the regulated community. But a
variety of petitioners, including the state of North Carolina and other downwind states, which
argued that the rule was not strong enough to address pollution from upwind sources, and some
individual utilities that felt they were unfairly treated by the rule’s emission budgets, challenged
the rule in the D.C. Circuit, and the court vacated it July 11, 2008. A unanimous court found that
although EPA had established a “significant contribution” made by power plants to nonattainment
8 The rule appeared in the Federal Register two months later. 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.
9 70 Federal Register 28606, May 18, 2005.
10 See U.S. EPA, Office of Air and Radiation, Regulatory Impact Analysis for the Final Clean Air Interstate Rule,
March 2005, pp. 3-3 and 3-4, at http://www.epa.gov/cair/pdfs/finaltech08.pdf.
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of standards and failure to maintain standards in downwind states, as required by Section 110 of
the Clean Air Act, the agency’s methodology for establishing emission budgets for each state was
unrelated to the state’s contribution to the nonattainment and maintenance problems in specific
downwind states.11 The court also found that the choice of 2015 for a second phase compliance
deadline, based on technological and economic feasibility, ignored EPA’s statutory mandate. It
found the fuel adjustment factors in the rule (which set more stringent requirements for natural
gas- and oil-fired plants than for coal-fired ones) to be arbitrary and capricious. It concluded:
“CAIR’s flaws are deep. No amount of tinkering ... will transform CAIR, as written, into an
acceptable rule.”12 On December 23, 2008, the court modified its decision, allowing CAIR to
remain in effect until a new rule is promulgated by EPA. 13
Although they differ on the details of what they support, states, electric utilities, and
environmental groups have all supported a replacement that is similar to CAIR in many respects.
Without CAIR, most eastern states would have an enormous challenge in achieving ambient air
quality standards through in-state emission reductions. For the utilities, CAIR was designed to
build on the existing regulatory framework of cap-and-trade programs under the acid rain
program and the “NOx SIP Call.”14 Anticipating the ability to bank and trade emission allowances
under CAIR, numerous utilities had already installed equipment to meet or exceed CAIR’s
requirements, the first phase of which have now been implemented. Environmental groups have
argued for a stronger version of CAIR—particularly its second phase, to be implemented in
2015—but they generally support the basic approach.
EPA’s CAIR Replacement: The Cross-State Air Pollution Rule
On July 6, 2011, EPA finalized a replacement for CAIR, the Cross-State Air Pollution Rule
(CSAPR, generally pronounced as “Casper”).15 CSAPR would leave the CAIR Phase 1 limits in
place and would have set new limits replacing CAIR’s second phase in 2012 and 2014, up to
three years earlier than CAIR would have.
The CAIR Phase 1 rules appear to have already had a substantial effect. In 2010, EPA reports,
SO2 emissions from fossil-fueled power plants in the lower 48 states (at 5.1 million tons) were
49% below 2005 levels. NOx emissions from the same sources declined to 2.1 million tons in
2010, 42% less than in 2005.16
CSAPR would build on these reductions. It would have established a second and third phase of
reductions in 2012 and 2014, with particular emphasis on SO2—emissions of which would
decline to 2.4 million tons in the covered states (73% below 2005 levels) in 2014. The rule would
cover 28 Eastern, Midwestern, and Southern states and the District of Columbia.
11 North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008).
12 Ibid. at 930.
13 North Carolina v. EPA, 550 F.3d 1176 (D.C. Cir. 2008).
14 The acid rain program, established by the Clean Air Act Amendments of 1990, set up a cap-and-trade program for
sulfur dioxide emissions from electric generating units. Implementation began in 1995. The NOx SIP Call,
implemented in 2004, is a cap-and-trade program for control of nitrogen oxide emissions in the eastern half of the
country.
15 The rule appeared in the Federal Register, August 8, 2011. For more details, including a link to the Federal Register
notice, see http://www.epa.gov/crossstaterule/actions.html.
16 Data are from EPA’s National Emissions Inventory, at http://www.epa.gov/ttn/chief/trends/.
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CSAPR is a modified cap-and-trade rule. It would set emission caps in each of the covered states
and allow unlimited trading of allowances within the individual states. Interstate trading would be
allowed so long as a state remains within 18%-21% of its emissions caps. Limiting interstate
trading was intended to address the D.C. Circuit’s ruling, which found CAIR’s unlimited
interstate allowance trading program unlawful.
To hasten implementation, EPA promulgated a Federal Implementation Plan (FIP) for each of the
states: the FIPs specified emission budgets for each state based on controlling emissions from
electric power plants. States may develop their own State Implementation Plans and may choose
to control other types of sources if they wish, but the federal plan was to take effect until the state
acts to replace it.
EPA estimates that CSAPR would cost the power sector $2.4 billion annually in 2014, but it
expects the benefits to be 50 to 120 times as great—an estimated $120 billion to $280 billion
annually. The most important benefit would be 13,000 to 34,000 fewer premature deaths annually.
Avoided deaths and other benefits occur throughout the East, Midwest, and South, according to
EPA, with Ohio and Pennsylvania benefitting the most.17
Criticism of the Cross-State rule initially focused on the short time frame for implementation, and
the adequacy of the emission “budgets” for some of the covered states. Questions regarding the
adequacy of the compliance time frame focused on Phase 1 of the rule, which was to take effect
in 2012, just five months after the rule’s promulgation. EPA maintained that the deadline was
reasonable because no new equipment needed to be installed to meet the 2012 requirements.
Compliance could be achieved, according to the agency, by running existing pollution control
equipment more frequently or increasing power generation at cleaner generation units. (In fact,
preliminary estimates for 2012 show that—despite CSAPR being stayed, as discussed below—
emissions of SO2 and NOx declined by 36% and 19%, respectively, in 2012, largely as a result of
utilities switching to natural gas generation.18)
A second issue concerned the adequacy of the emissions budgets for individual states. Particular
controversy centered on Texas, which was included in the final rule, but not in the proposed
version. Following promulgation, EPA reviewed additional information submitted by Texas and
revised the rule to increase the state’s SO2 emissions cap by 29%; but the state remained opposed
to the rule.
Legislative and Judicial Options
In the 112th Congress, both the House and Senate considered legislation that would have revoked
the CSAPR rule. The House bill (H.R. 2401) passed 249-169, on September 23, 2011. The same
provisions were included in Title III of H.R. 3409, which the House passed in September 2012.
The Senate did not take up either House bill, but it did consider S.J.Res. 27, a resolution of
disapproval of CSAPR under the Congressional Review Act (CRA). It was rejected by the Senate,
41-56, on November 10, 2011. (For additional detail, see CRS Report R41563, Clean Air Issues
in the 112th Congress.)
17 U.S. EPA, Office of Air and Radiation, “Final Air Pollution Cross-State Air Pollution Rule,” Overview Presentation,
undated, pp. 12-14, at http://www.epa.gov/crossstaterule/pdfs/CSAPRPresentation.pdf.
18 U.S. EPA, Clean Air Markets Division, “Emissions Tracking Highlights,” at http://www.epa.gov/airmarkets/
quarterlytracking.html.
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Although unsuccessful in Congress, opponents of the CSAPR rule did prevail in court. At least 45
parties filed suit asking the D.C Circuit Court of Appeals to review the rule (the cases were
consolidated as EME Homer City Generation L.P. v. EPA ). On August 21, 2012, in a 2-1
decision, the court vacated and remanded the rule, finding that EPA’s imposition of Federal
Implementation Plans, without first giving the states an opportunity to develop their own plans,
was unlawful. The court also held that EPA’s emission budgets (which were based on what the
agency considered cost-effective controls) may require states to reduce their emissions by
amounts greater than their significant contribution to nonattainment in downwind states.19 The
agency subsequently petitioned the court for rehearing en banc, but the court denied the petition,
January 24. EPA has until April 24 to decide whether it will appeal to the Supreme Court.
Mercury and Air Toxics Standards
Background
The Clean Air Act also provides authority for EPA to regulate emissions of mercury and other
hazardous air pollutants (HAPs, or “air toxics”) from electric generation units. Much of this
discussion has focused on mercury. Electric generating units account for about half of all mercury
emissions in the United States.
Mercury is a persistent, bioaccumulative neurotoxin that can cause adverse health effects
(principally delayed development, neurological defects, and lower IQ in fetuses and children) at
very low concentrations. (For a discussion of mercury’s health effects, see CRS Report RL32420,
Mercury in the Environment: Sources and Health Risks.) The principal route of exposure to
mercury is through consumption of fish. Mercury enters water bodies, often through air
emissions, and is taken up through the food chain, ultimately affecting humans as a result of fish
consumption. All 50 states have issued fish consumption advisories due to mercury pollution,
covering 16.4 million acres of lakes, 1.1 million river miles, and the coastal waters of 16 entire
states.20
EPA was required by the 1990 Clean Air Act Amendments and a 1998 consent agreement to
determine whether regulation of mercury from power plants under Section 112 of the Clean Air
Act was appropriate and necessary. Section 112 is the section that regulates emissions of
hazardous air pollutants. In general, it requires EPA to set standards based on the Maximum
Achievable Control Technology (a term defined with great precision in the act), and to impose the
MACT standards at each individual emissions source. In a December 2000 regulatory finding,
EPA concluded that regulation of mercury from power plants under Section 112 was appropriate
and necessary.
Rather than promulgate MACT standards, however, EPA reversed its December 2000 finding in
March 2005, and established through regulations a national cap-and-trade system for power plant
emissions of mercury, the Clean Air Mercury Rule (CAMR). Under CAMR, the final cap would
have been 15 tons of emissions nationwide in 2018 (about a 70% reduction from 1999 levels,
when achieved).
19 EME Homer City Generation, L.P. v. EPA, 696 F.3d 7 (D.C. Cir. 2012).
20 U.S. EPA, “National Listing of Fish Advisories: Technical Fact Sheet 2010,” at http://water.epa.gov/scitech/
swguidance/fishshellfish/fishadvisories/technical_factsheet_2010.cfm.
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Under the cap-and-trade system, utilities could either control the pollutant directly or purchase
excess allowances from other plants that instituted controls more stringently or sooner than
required. As with the acid rain and CAIR cap-and-trade programs, early reductions under CAMR
could have been banked for later use, which the agency itself (in the Regulatory Impact Analysis
of the rule) said would result in utilities delaying compliance with the full 70% reduction until
after 2025.21 (For additional information on the mercury rule, see archived CRS Report RL32868,
Mercury Emissions from Electric Power Plants: An Analysis of EPA's Cap-and-Trade
Regulations.)
New Jersey v. EPA
The CAMR rule was challenged in petitions for review filed by New Jersey and 16 other states as
well as other petitioners.22 The D.C. Circuit, in a 3-0 decision handed down February 8, 2008
(New Jersey v. EPA), vacated the rule.23 The court found that once the agency had listed electric
generating units (EGUs) as a source of hazardous air pollutants, it had to proceed with MACT
regulations under Section 112 of the act unless it “delisted” the source category, under procedures
the act sets forth in Section 112(c)(9). The procedures would require the agency to find that no
EGU’s emissions exceeded a level adequate to protect public health with an ample margin of
safety, and that no adverse environmental effect would result from any source—a difficult test to
meet, given the agency’s estimate that EGUs were responsible for 46% of mercury emissions
from all U.S. sources at the time. Rather than delist the EGU source category, the agency had
maintained that it could simply reverse its December 2000 “appropriate and necessary” finding, a
decision that was much simpler because there were no statutory criteria to meet. The court found
this approach unlawful. “This explanation deploys the logic of the Queen of Hearts, substituting
EPA’s desires for the plain text of Section 112(c)(9),” the court said in its opinion.24
Other Mercury / Air Toxics Issues
Besides the question of whether EPA complied with the law’s requirements, critics found other
reasons to oppose EPA’s cap-and-trade approach to controlling mercury. One of the main
criticisms has been that it would not address “hot spots,” areas where mercury emissions and/or
concentrations in water bodies are greater than elsewhere. In fact, under a cap-and-trade system,
nothing would prevent emissions from increasing at hot spots.
Many also argued that the mercury regulations should have been more stringent or implemented
more quickly than the cap-and-trade regulations would have required. These arguments found a
receptive audience in the states: about 20 states have promulgated requirements stricter than the
federal Clean Air Mercury Rule program, with several requiring 80% to 90% mercury reductions
before 2010. (For additional information, see archived CRS Report RL33535, Mercury Emissions
from Electric Power Plants: States Are Setting Stricter Limits.)
21 U.S. EPA, Regulatory Impact Analysis of the Final Clean Air Mercury Rule, Table 7-3, p. 7-5, at
http://www.epa.gov/ttnecas1/regdata/RIAs/mercury_ria_final.pdf.
22 Seven other states joined EPA in defending the rule.
23 New Jersey v. EPA, 517 F.3d 574 (D.C. Cir. 2008).
24 Id. at 582.
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CAMR also didn’t address emissions of hazardous air pollutants other than mercury. According to
EPA, EGUs are sources of 12 other HAPs, including three acid gases and nine toxic metals.25
The Utility MACT / Mercury and Air Toxics Standards
On February 16, 2012, EPA responded to the New Jersey v. EPA court decision by promulgating
what is referred to as the “Utility MACT” or the Mercury and Air Toxics Standards (MATS).26
The standards have been widely debated: between proposal and promulgation, the agency is
reported to have received 960,000 public comments on them.
MATS requires coal-fired power plants to achieve a 91% reduction from uncontrolled emissions
of mercury, nine other toxic metals, and three acid gases, all of which were listed by Congress as
hazardous air pollutants in the 1990 Clean Air Act Amendments. According to EPA, power plants
are the largest emitters of many of these pollutants, accounting for about 50% of the nation’s
mercury emissions, 62% of its arsenic emissions, and 82% of its hydrochloric acid emissions, for
example.27 The MATS rule is also projected to reduce emissions of fine particulates (PM2.5);
although PM2.5 is not listed as a hazardous air pollutant, EPA believes that the MATS rule’s effect
on PM2.5 will lead to the avoidance of up to 11,000 premature deaths each year.
In proposing the standards, EPA noted that while the requirements are stringent for those facilities
lacking controls, 56% of existing coal-fired power plants already are equipped with controls that
will allow them to meet the standards. Thus, the standards are expected to level the playing field,
bringing older, poorly controlled plants up to the standards capable of being achieved by a
majority of the existing units. In this respect, the proposed standards reflect the statute’s
requirement that existing sources of HAPs should meet standards based on the current emissions
of the best performing similar sources.
The agency also concludes that some plants would be retired by 2015, rather than invest in
control technologies. In all, it says, coal-fired generation would decline about 2% as a result of
the MATS rule. Coal-fired capacity is, of course, simultaneously being buffeted by market forces,
principally the low cost of natural gas. As a result, more than that 2% of coal-fired generation is
being retired. (For additional discussion, see CRS Report R42144, EPA’s Utility MACT: Will the
Lights Go Out?)
In its Regulatory Impact Analysis,28 EPA projected the annual cost of compliance with the MATS
rule at $9.6 billion. The average consumer would see an increase of $3-$4 per month in the cost
of electricity due to the rule, according to the agency. These costs will go largely to the
installation of scrubbers and fabric filters. In most cases, the fabric filters will be coupled with
activated carbon injection or dry sorbent injection. Mercury and other HAPs become attached to
25 See U.S. EPA, “Memorandum: Emissions Overview: Hazardous Air Pollutants in Support of the Final Mercury and
Air Toxics Standard,” November 2011, Tables 4, 5, and 6, at http://www.epa.gov/airquality/powerplanttoxics/pdfs/
20111216EmissionsOverviewMemo.pdf. Hereinafter, “EPA Emissions Overview.”
26 The rule appeared in the Federal Register, February 16, 2012, at 77 Federal Register 9304. For a link to the rule as
well as explanatory material, see U.S. EPA, “Final Mercury and Air Toxics Standards (MATS) for Power Plants,” at
http://www.epa.gov/airquality/powerplanttoxics/actions.html.
27 EPA Emissions Overview, previously cited.
28 U.S. EPA, Regulatory Impact Analysis for the Final Mercury and Air Toxics Standards, at http://www.epa.gov/ttn/
ecas/regdata/RIAs/matsriafinal.pdf.
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the carbon or sorbent after it is injected into the flue gas, and the fabric filter collects the particles,
removing them from the plant’s emissions.
This is not complicated or new technology. Other types of facilities (notably solid waste
incinerators) have used this technology for the past 15 years to reduce their mercury emissions by
95% or more. Moreover, as a result of state-level pollution control regulations, a growing
percentage of coal-fired plants do the same. EPA estimates that about one-fifth of U.S. coal-fired
electric generating capacity would have either activated carbon or dry sorbent injection in 2015
without the rule.
The benefits of the rule are estimated by EPA at $37 billion to $90 billion annually—4 to 9 times
as great as the costs—due primarily to the avoidance of 4,200 to 11,000 premature deaths each
year. Other benefits, only some of which were given dollar values, include the annual avoidance
of 4,700 nonfatal heart attacks, 130,000 asthma attacks, and developmental effects on children,
including effects on IQ, learning, and memory.
Legislative and Judicial Action
Like the CSAPR rule, the MATS rule has been challenged both in Congress and in the courts. In
the 112th Congress, H.R. 2401 and H.R. 3409 would have declared the MATS rule “of no force
and effect,” would have required that any replacement rule impose the least burdensome
regulatory alternative among those authorized under the Clean Air Act, and would have delayed
compliance with any replacement rule until six years after an interagency panel completed a study
of the cumulative impact of numerous listed EPA rules. The Senate did not consider either bill,
but it did consider S.J.Res. 37, a resolution to disapprove the MATS rule under the Congressional
Review Act. The resolution was rejected by the Senate, 46-53, on June 20, 2012.
The regulations have also been challenged in the D.C. Circuit Court of Appeals (White Stallion
Energy Center v. EPA). Oral argument is likely in spring or summer of 2013. Petitioners have
focused on EPA’s “appropriate and necessary” finding, arguing that the agency found few direct
benefits from controlling mercury or other air toxics. The vast majority of the monetized benefits
in EPA’s analysis come from reduced emissions of PM2.5, which the pollution control equipment
would achieve as a co-benefit.
In the meantime, in response to petitions by numerous parties, EPA has agreed to reconsider
portions of the MATS rule.29 On November 16, 2012, the agency proposed to modify the rule’s
standards for mercury emissions from new coal-fired power plants: the proposed modifications, if
finalized, will allow 15 times as much mercury to be emitted as would have been allowed under
the final standard promulgated in February 2012. The proposed change responds to comments
from the Institute of Clean Air Companies (the trade association that manufactures pollution
control and monitoring equipment) and others that the mercury standard as originally
promulgated was an order of magnitude below a level that could be measured by continuous
monitoring equipment.
29 U.S. EPA, “Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards for
Hazardous Air Pollutants from Coal- and Oil-Fired Electric Utility Steam Generating Units and Standards of
Performance for Fossil-Fuel-Fired Electric Utility, Industrial-Commercial-Institutional, and Small Industrial-
Commercial-Institutional Steam Generating Units,” Proposed Rules, November 16, 2012, at http://www.epa.gov/
airquality/powerplanttoxics/pdfs/20121116proposal.pdf.
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The reconsideration would also make the new source standards for particulate matter and
hydrogen chloride less stringent, allowing 13 times as much particulate matter and 25 times as
much hydrogen chloride; these changes were based on the agency’s conclusion that it had not
used all the available emissions information in the record when it promulgated the February 2012
standards. The agency says that the proposed changes will result in “no significant change in
costs, emission reductions or health benefits from MATS.” Facilities will still need the same
pollution control equipment to meet the less stringent standards.30
Cumulative Impacts of EPA Rules
As EPA has developed and proposed standards for electric generating units, utilities that rely
heavily on coal-fired power and the industry’s trade association, the Edison Electric Institute
(EEI), have raised concerns about the cumulative impacts of EPA rules. Besides the CSAPR and
MATS rules, their attention has focused on proposed Clean Water Act rules for cooling water
intake structures, proposed Solid Waste Disposal Act standards for managing coal combustion
wastes, and potential Clean Air Act standards for emissions of greenhouse gases. Cumulatively,
many in the industry and other opponents of these regulations have referred to these rules as an
impending “train wreck” for coal-fired power plants. They maintain that compliance will be
difficult and costly within the mandated timeframes, and that, as a result, sections of the country
depending on coal-fired power could experience electricity reliability problems as plants are
retired or taken off-line for retrofit of pollution controls.
Others in the industry and in various think tanks have concluded that this is unlikely to be the
case. They note that the studies sponsored by EEI and by coal-reliant utilities were generally
written before EPA proposed or promulgated any of the actual regulations, and the studies often
assumed far more stringent requirements than EPA actually proposed or promulgated. While it is
true that many coal-fired units would have to be taken out of service for pollution control
equipment to be installed, the next few years would be an opportune time to do so, as there is
currently substantial excess generating capacity in the electric power industry. This reserve
margin will continue to be available over the next 5-10 years: as a result of the recession and the
slow pace of economic recovery, demand for electricity is growing slowly.
Many observers note, too, that EPA regulation is only one element of the situation facing aging
coal-fired power plants, many of which are more than 40 years old and have few pollution
controls. Equally important is competition from more efficient natural gas combined cycle units,
which have taken over a larger share of the electric power market as the price of natural gas has
declined. Over the last two decades, more than 80% of new generating capacity has come from
these gas-fired units, which are relatively cheap to build and are cleaner and more efficient to
operate than many coal-fired units. Observing the inroads being made by gas-fired generation,
many industry observers conclude that portions of the electric power industry are simply
experiencing a transition to more efficient power generation sources. (For additional information
on this subject, see CRS Report R41914, EPA’s Regulation of Coal-Fired Power: Is a “Train
Wreck” Coming?, and CRS Report R42144, EPA’s Utility MACT: Will the Lights Go Out?)
30 U.S. EPA, “Fact Sheet, Proposed Updates of the Limits for New Power Plants Under the Mercury and Air Toxics
Standards (MATS),” at http://www.epa.gov/airquality/powerplanttoxics/pdfs/20121116factsheet.pdf. See also 77
Federal Register 71333, November 30, 2012.
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If the cost of making a coal-fired plant more efficient and less polluting is higher than that of
converting to natural gas, the plant may well be retired. This can cause economic dislocation in
specific communities, but it might not cause a substantial increase in the price of electricity or
threaten the reliability of electricity supply. In 2012, for example, as coal-fired generation
declined from 42% to 37% of total electric power, the price of electricity declined by 0.3%.31
In the 112th Congress, legislation to address the cumulative impacts issue was introduced in both
the House and Senate. H.R. 2401, the Transparency in Regulatory Analysis of Impacts on the
Nation (TRAIN) Act of 2011, which the House passed September 23, 2011, would have:
• established a panel of representatives from 11 federal agencies to report to
Congress by August 2012 on the cumulative economic impact of a number of
listed EPA rules, guidelines, and actions concerning clean air and waste
management;
• rendered both the Cross-State rule and the MATS rule “of no force and effect”;
• reinstated the CAIR rule to replace the Cross-State rule for at least six years
following enactment;
• required that any subsequent replacement allow trading of emission allowances
among entities irrespective of the states in which they are located;
• delayed promulgation of a replacement for the MATS rule until at least one year
after submission of the cumulative impacts report and delayed compliance for at
least five years after that date;
• required that the MATS replacement impose the least burdensome regulatory
alternative from among the alternatives authorized under the Clean Air Act; and
• required EPA to take into consideration feasibility and cost in setting health-
based ambient air quality standards.
The same provisions passed the House a second time as Title III of H.R. 3409, the Stop the War
on Coal Act, September 19, 2012. The Senate did not take action on either bill.
Air Quality Standards
The Obama Administration’s EPA has also reviewed several national ambient air quality
standards (NAAQS), as it is required to do by Section 109 of the Clean Air Act. NAAQS don’t
directly regulate emissions from sources of pollution; rather, they represent EPA’s formal
judgment regarding how clean the air must be to protect public health and welfare. The standards
set in motion monitoring and planning requirements, which in turn can lead to designation of
“nonattainment areas” and the imposition of emission controls.
31 U.S. Energy Information Administration, Electric Power Monthly, January 2013, Table ES1.B.
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Background
Air quality has improved substantially since the passage of the Clean Air Act in 1970: annual
emissions of the six air pollutants for which EPA has set ambient air quality standards (ozone,
particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, and lead) have declined by
202 million tons (68%), despite major increases in population, motor vehicle miles traveled, and
economic activity.32 Nevertheless, the goal of clean air continues to elude many areas, in part
because scientific understanding of the health effects of air pollution has caused EPA to tighten
standards for most of these pollutants. Congress anticipated that the understanding of air
pollution’s effects on public health and welfare would change with time, and it required, in
Section 109(d) of the act, that EPA review the standards at five-year intervals and revise them, as
appropriate.
The most widespread problems involve ozone and fine particles. As of December 2012, 118
million people lived in areas classified “nonattainment” for the ozone NAAQS; 74 million lived
in areas that were nonattainment for the fine particle (PM2.5) NAAQS.33 EPA attributes at least
33,000 premature deaths and millions of lost work days annually to exceedances of the PM2.5
standard. Recent research has tied ozone pollution to premature mortality as well.
Violations of the ambient air quality standards for the other four criteria pollutants are not as
widespread, but EPA is engaged in (or has recently completed) reviews indicating that health
effects of most of these pollutants are more serious than previously thought. As recently as 2010,
for example, no areas exceeded the NAAQS for sulfur dioxide (SO2), but in a review concluded
in that year, EPA determined that between 2,300 and 5,900 premature deaths could be avoided
annually by strengthening that standard.34 A review of the lead standard completed in 2008
concluded that it should be lowered by 90%,35 as a result of which nearly 10 million people are
considered to live in areas with unhealthy levels of atmospheric lead.36
CRS Report R41563, Clean Air Issues in the 112th Congress, summarized EPA’s recent efforts to
review the NAAQS and implement revisions, including the next steps for each of the six criteria
pollutants. Reviews of all six pollutants (ozone, PM, lead, NO2, carbon monoxide, and SO2) have
been completed since 2006, with the standards being made more stringent for five of the six. The
next round of reviews has begun for ozone and lead.
Reviews don’t always lead to revision of the standards. On August 31, 2011, the EPA
Administrator completed a review of the carbon monoxide (CO) NAAQS without changing the
standard. The CO standard was promulgated in its present form in 1971.
32 For additional data on air pollution trends, see http://www.epa.gov/airtrends/aqtrends.html#comparison.
33 Data for ozone nonattainment areas are from the U.S. EPA “Green Book,” at http://www.epa.gov/oar/oaqps/greenbk/
gntc.html. Data for PM2.5 nonattainment areas are also from the “Green Book,” at http://www.epa.gov/oar/oaqps/
greenbk/rnsum.html.
34 U.S. EPA, “Revisions to the Primary National Ambient Air Quality Standard, Monitoring Network and Data
Reporting Requirements for Sulfur Dioxide (SO2),” Text Slides, June 2010, p. 21, at http://www.epa.gov/air/
sulfurdioxide/pdfs/20100603presentation.pdf..
35 U.S. EPA, “Fact Sheet, Final Revisions to the National Ambient Air Quality Standards for Lead,” 2008, at
http://www.epa.gov/air/sulfurdioxide/pdfs/20100603presentation.pdf.
36 U.S. EPA, Green Book, at http://www.epa.gov/oaqps001/greenbk/popexp.html.
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Ozone and PM NAAQS Reviews
In the last three years, two NAAQS reviews, for ozone and for PM, have proven particularly
controversial. The next sections provide a brief discussion of the two reviews.
Ozone
On January 19, 2010, EPA proposed a revision to the NAAQS for ozone.37 The proposal did not
follow the usual five-year (or longer) review process, but resulted from the EPA Administrator’s
decision to reconsider standards promulgated in March 2008 by the previous Administration. The
2008 review had made the standards more stringent; but EPA suspended implementation of the
new standard in September 2009 in order to consider further strengthening it, and proposed a
more stringent standard in January 2010.
As proposed, the January 2010 revision would have lowered the primary (health-based) standard
from 75 parts per billion (ppb) averaged over 8 hours (the standard set in 2008) to somewhere in
the range of 70 to 60 ppb; it would also have set a new secondary standard designed to protect
crops and forests from ozone. The proposal followed the recommendations of the agency’s panel
of outside scientific advisers, the Clean Air Scientific Advisory Committee (CASAC), which had
concluded that the 2008 revision did not meet the Clean Air Act’s statutory requirements.
Because of its wide reach and potential cost, the proposed revision was among the most
controversial rules under consideration at EPA at the time. EPA is prohibited by the statute from
considering costs in setting NAAQS,38 but it does prepare cost and benefit estimates for
information purposes, and in order to comply with Executive Order 12866 (under which the
Office and Management and Budget (OMB) requires cost-benefit analysis of economically
significant rules). When it proposed the 2010 revisions, the agency estimated that the costs of
implementing the revised ozone NAAQS would range from $19 billion to $25 billion annually in
2020 if the standard chosen were 70 ppb, or $52 billion to $90 billion if the standard chosen were
60 ppb, with benefits of roughly the same amount.39 EPA identified at least 515 counties that
would violate the NAAQS if the most recent three years of data available at the time of proposal
were used to determine attainment (compared to 85 counties that violated the 1997 standard in
effect at that time).
Initially, the agency said it would complete the ozone review by August 2010, but it announced
delays in the projected completion date four times, before sending a final decision to OMB for
interagency review in July 2011. The agency’s final decision would have set a 70 ppb primary
standard and would have adopted the new form of the secondary standard that the agency had
37 U.S. Environmental Protection Agency, “National Ambient Air Quality Standards for Ozone; Proposed Rule,” 75
Federal Register 2938, January 19, 2010.
38 The Clean Air Act’s §108 and §109 have been so interpreted since the NAAQS provisions were added to the act in
1970; in 2001, this interpretation was affirmed in a unanimous Supreme Court decision, Whitman v. American
Trucking Associations, 121 S. Ct. 903 (2001). This is not to say that cost considerations play no role in Clean Air Act
decisions: cost-effectiveness is considered extensively by EPA and the states in selecting emission control options. But
in deciding what level of ambient pollution poses a health threat, the statute bars consideration of costs.
39 U.S. EPA, “Fact Sheet: Supplement to the Regulatory Impact Analysis for Ozone,” January 7, 2010, at
http://www.epa.gov/air/ozonepollution/pdfs/fs20100106ria.pdf.
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proposed. The agency’s cost estimate was unchanged from the proposal—$19 billion to $25
billion in 2020—and benefits were estimated to be roughly the same amount.40
On September 2, 2011, the White House announced that the President had requested that EPA
Administrator Jackson withdraw the all-but-final ozone standards from further consideration at
that time. The President’s statement noted that “work is already underway to update a 2006
review of the science that will result in the reconsideration of the ozone standard in 2013,” and
stated that he did not “support asking state and local governments to begin implementing a new
standard that will soon be reconsidered.”41
State and local governments are being asked to begin implementing a new standard that will soon
be reconsidered, however: withdrawal of the decision left EPA and state and local governments to
implement the 2008 ozone standards, which had been stayed pending the agency’s
reconsideration. Withdrawing the proposed standards also meant that legal challenges to the 2008
standard (Mississippi v. EPA42), which had been stayed pending reconsideration, could proceed.
The D.C. Circuit heard oral argument in that case on November 16, 2012.
Since September 2011, EPA has proceeded with the regularly scheduled five-year review of the
2008 standard, as the President indicated the agency would. Proposed revisions as a result of this
review are expected before the end of 2013, with final decisions late in 2014. The 113th Congress
is likely to take a keen interest in the results of this review.
Particulate Matter (Including “Farm Dust”)
The other NAAQS review that was controversial in the 112th Congress—and may continue to be
in the 113th—is the review of the particulate matter (PM) standard. EPA considers particulate
matter to be among the most serious air pollutants, responsible for tens of thousands of premature
deaths annually.
The current NAAQS sets standards for both “fine” particulates (PM2.5) and larger, “coarse”
particles (PM10). Of the two types of particulates, PM2.5 is considered the more significant threat
to health; the PM2.5 standards also affect far more people and far more counties than the standard
for PM10.
EPA completed a review of the PM NAAQS in 2006. The agency is required by the Clean Air Act
to review NAAQS at five-year intervals, so another review was due in 2011. As the review
process was getting underway, in February 2009, the D.C. Circuit Court of Appeals remanded the
2006 standard for PM2.5 to EPA, saying that the standard was “contrary to law and unsupported
by adequately reasoned decisionmaking.” 43 As a result, EPA combined the statutory five-year
40 The estimated costs compared implementation of a 70 ppb primary standard to a baseline that assumed compliance
with the 1997 ozone standard. Implementing the 2008 ozone standard, which the agency is now doing, will cost $7.6
billion to $8.8 billion in 2020 compared to the same baseline, according to the agency; so the incremental cost of the 70
ppb standard would have been on the order of $11 billion to $16 billion. See U.S. EPA, Regulatory Impact Analysis,
Final National Ambient Air Quality Standard for Ozone, July 2011, p.6, at http://www.epa.gov/airquality/
ozonepollution/pdfs/201107_OMBdraft-OzoneRIA.pdf.
41 The White House, Office of the Press Secretary, “Statement by the President on the Ozone National Ambient Air
Quality Standards,” September 2, 2011.
42 Mississippi v. EPA, No. 08-1200 (D.C. Cir. filed 5/23/2008).
43 American Farm Bureau Fed'n v. EPA, 559 F.3d 512 (D.C. Cir. 2009).
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review of the standard and its response to the D.C. Circuit decision, completing a review of the
PM standard that served both purposes in December 2012.44 The review left the standard for
coarse particles unchanged, as well as the standard for 24-hour exposures to PM2.5. But it lowered
the standard for annual exposures to PM2.5, as suggested by the agency’s outside scientific
advisers,45 from 15 micrograms per cubic meter to 12.
Although this appears to be a significant strengthening of a standard that potentially affects a
wide array of mobile and stationary sources, EPA projects the incremental cost of the revision at a
relatively modest $53 million to $350 million annually. (By way of comparison, as noted earlier,
the proposed ozone NAAQS revision in 2010 was projected to cost at least $19 billion per year.)
The cost of compliance with the PM NAAQS is moderated by the fact that other EPA standards
are reducing exposures to PM2.5 even without a strengthening of the ambient standard. Annual
benefits were estimated to range from $4.0 billion to $9.1 billion.46
In the 112th Congress, attention to PM issues focused on the larger, coarse particles, PM10, even
though EPA did not propose to change them. Members of the House and Senators discussed the
need to prevent a supposed EPA plan to use the revision of the PM10 standard to impose controls
on “farm dust.” The House passed legislation to prevent EPA from tightening standards for PM10
for one year and to permanently limit EPA’s authority to regulate dust in rural areas. EPA stated
early in the PM review process that it did not intend to change the PM10 standard. The final
revision made no change.
(For additional information on the PM standards, see CRS Report R42934, Air Quality: EPA’s
2013 Changes to the Particulate Matter (PM) Standard.)
Other Issues
Since 2009, EPA has proposed and promulgated numerous regulations implementing the Clean
Air Act (and other pollution control statutes that it administers). Critics of the Administration,
both within Congress and outside of it, have accused the agency of reaching beyond the authority
given it by Congress and ignoring or underestimating the costs and economic impacts of these
rules. At least seven bills that would have overturned specific regulations or limited the agency’s
authority (H.R. 1, H.R. 910, H.R. 1633, H.R. 2250, H.R. 2401, H.R. 2681, and H.R. 3409 )
passed the House in the 112th Congress.
In addition to the regulation of greenhouse gas emissions, power plants, and NAAQS, discussed
above, two of the EPA regulations that attracted the most attention were the Maximum
Achievable Control Technology standards for cement kilns and boilers (referred to as the
“Portland Cement MACT,” and the “Boiler MACT,” respectively). In both cases, EPA agreed to
reconsider rules that it had promulgated. On December 20, 2012, EPA Administrator Jackson
44 The rule appeared in the Federal Register, January 15, 2013, at 78 Federal Register 3086.
45 Section 109(d) of the Clean Air Act required the EPA Administrator to appoint an independent scientific review
committee, the Clean Air Scientific Advisory Committee (CASAC), which reviews EPA’s staff work in setting
NAAQS. The Administrator is not required to follow CASAC recommendations, but she must set forth CASAC’s
findings and, if the NAAQS differs from CASAC recommendations, provide an explanation in the Federal Register of
the reasons for such differences.
46 For additional information, see U.S. EPA, “Overview of EPA’s Revisions to the Air Quality Standards for Particle
Pollution (Particulate Matter),” at http://www.epa.gov/pm/2012/decfsoverview.pdf.
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signed revised rules for both, giving the affected industries additional time to comply, and making
the final standards less stringent than those originally promulgated.47
While EPA has been widely criticized by industry groups and many in Congress for overreaching,
the agency maintains that in promulgating these and other rules, it is complying with statutory
mandates placed on the agency by Congress. The agency states that its critics’ focus on the cost of
controls obscures the benefits of new regulations, which, it estimates, far exceed the costs; and it
maintains that pollution control is an important source of economic activity, exports, and
American jobs.
Environmental groups generally disagree that the agency has overreached in setting Clean Air Act
standards. These groups often maintain that the agency’s standards are not stringent enough, don’t
meet statutory requirements, or disregard the findings of the agency’s science advisors. The result
is that EPA Clean Air Act standards generally are challenged in court both by industry and by
environmental groups, with various states supporting each side. The resulting court decisions
often set EPA’s agenda as much as Congress or the Administration.
Confirmation of a new EPA Administrator as well as oversight hearings are likely to give the
113th Congress early venues to revisit these issues. For additional discussion of EPA’s regulatory
actions, primarily under the Clean Air Act, but also under other statutes, see CRS Report R41561,
EPA Regulations: Too Much, Too Little, or On Track?
Author Contact Information
James E. McCarthy
Specialist in Environmental Policy
jmccarthy@crs.loc.gov, 7-7225
47 The Boiler MACT standards were published January 31, 2013, at 78 Federal Register 7138. The Portland Cement
rule was published February 12, 2013, at 78 Federal Register 10006.
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