| Clean Air Act |
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The Clean Air Act (CAA) is the core law that establishes a comprehensive national program for reducing emissions from factories, cars, and other sources in order to protect human health and the environment. The law directs the federal Environmental Protection Agency (EPA) to establish national clean air standards, but then gives the states and tribes an opportunity to take a lead role in meeting those standards. The law also gives EPA the responsibility for setting emissions limits for many sources of pollution, including cars and trucks (mobile sources) as well as factories and power plants (stationary sources). Both EPA and the states can go to court to enforce air quality laws; in addition, citizens and businesses can challenge many EPA decisions in court.
Clean Air Act
Key Concepts National Ambient Air Quality Standards Attainment and Nonattainment Areas State and Tribal Implementation Plans Hazardous Air Pollutants Mobile Sources New Source Review (NSR) Permits Citizen Suits Process Essentials: Protecting Clean Air Areas Class 1, 2 and 3 Areas Prevention of Significant Deterioration Visibility Protection Energy Development in the Powder River Basin Western Coal at the Crossroads Greenhouse Gas Emissions Clean Air Act Legislation of the 111th Congress Key ConceptsNational Ambient Air Quality Standards (NAAQS)The Clean Air Act (CAA) requires the Environmental Protection Agency (EPA) to set national clean air goals for a defined set of air pollutants (NAAQS), but then allows states (and Indian tribes) to take on much of the responsibility for achieving those goals. The first steps in this process require EPA to identify air pollutants that come from many sources and which might endanger public health or the environment. Then EPA assembles experts who develop a document that explains the criteria for why the air pollutant should be regulated (so they are called "criteria pollutants"). So far, EPA has only identified six criteria pollutants, but they are ubiquitous in our society: sulfur dioxide, particulate matter, nitrogen oxide, carbon monoxide, ozone (which is created by the chemical interaction of other pollutants), and lead. EPA sets nationally applicable limits for these pollutants to protect our health. These are called "primary standards." EPA also sets "secondary standards" -- limits on these pollutants to protect visibility and prevent damage to crops, buildings, and so on.In January 2010, the EPA issued a draft rule aimed at tightening the standards for ground-level ozone, or smog, proposing to set the health-based "primary" standard for smog within a range of 60 to 70 parts per billion (ppb) when averaged over an 8-hour period. The EPA also proposed a "secondary" standard of 7 to 15 parts per million-hours, aimed at protecting vegetation and ecosystems, including parks, wildlife refuges and wilderness areas. Attainment and Nonattainment AreasOnce EPA sets nationally applicable air quality standards, it then examines monitoring data to determine which areas meet those nationally applicable standards, and which do not. Those areas that meet the nationally applicable standards are called "attainment" areas, while those that do not are called "nonattainment" areas (described in EPA's Green Book).For example, in November 2009, the EPA released a final rule establishing the initial air quality designations for most areas in the United States, including Indian Country, for the 2006 24-hour fine particle National Ambient Air Quality Standards. States with areas designated nonattainment must undertake certain planning and pollution control activities within these areas in order to attain the standards as quickly as reasonably possible. Attainment can be more difficult in eastern states, which receive pollution from industrial activities outside their borders. In the summer of 2010, the EPA proposed a new Clean Air Transport Rule, aimed at reducing SO2 emissions by 71 percent and NOx emissions by 52 percent by 2014. Some advocates objected that the standards should be higher, reflecting stricter ozone standards proposed earlier in 2010. The EPA responded that it would revise the Transport Rule to reflect higher standards when they take effect. State and Tribal Implementation PlansOnce EPA decides that one or more areas of a state have air that is dirtier than what the nationally applicable standards require, then the focus shifts to states and tribes with EPA-approved air quality programs. If a state has an approved program, it must develop a plan for how it will bring the area back into compliance with the air quality standards. The state develops a state implementation plan -- known as a SIP -- to explain how it will reduce emissions, and from what sources. For example, the state could require some factories or other major sources to install reasonably available control technologies (RACT) to reduce emissions and bring the area into compliance with the CAA.In 1990, the Congress also authorized tribes to develop air quality programs similar to those adopted by states. By 2005, 20 tribes had received a delegation of CAA authority under EPA's Tribal Authority Rule (TAR). If EPA approves a tribal air program, then the tribe is responsible for developing a tribal implementation plan (TIP). At least two tribes have submitted implementation plans including the Gila River Indian Community. The Southern Ute Tribe has also recently taken major steps towards regulating their air quality through a tribal administered program. See "Southern Ute tribe's air code on track toward approval," Durango Herald News, 5/11/10. On April 5, 2010, the EPA provided notice that it is revising its regulations relating to the Clean Air Act requirement that federal actions conform to the appropriate state, tribal, or federal implementation plan for attaining clean air. Hazardous Air PollutantsThe CAA deals with hazardous air pollutants, which may pose serious health risks, differently than it deals with other air pollutants such as carbon monoxide that is emitted from cars and trucks, or sulfur dioxide that is emitted from power plants. The CAA identifies almost 200 hazardous air pollutants and the kinds of facilities that emit those pollutants. EPA can add and delete pollutants from that list. In the case of hazardous air pollutants, EPA determines what technology should be installed at each type of facility to achieve the maximum achievable reductions in emissions of these pollutants. Once those technologies are in place for a while, EPA can also assess whether a health risk is still present. If they decide there is a residual health risk, the agency can require even more stringent controls on emissions.As part of its toxic air pollutants program, EPA maintains a Toxics Release Inventory (TRI) database. This database includes information for the public about releases of toxic chemicals from manufacturing facilities into the environment through the air, water, and land. You can access the data by typing in your zip code. Mobile Sources
U.S. Supreme Court forces EPA into Climate Change Controversy over Motor Vehicles
Throughout the history of the CAA, Congress has recognized that cars and trucks--referred to as "mobile sources"--are significant contributors to air pollution, but that people and vehicles are highly mobile. For example, a car sold in California could end up being driven in New York state. The CAA therefore establishes nationally applicable rules for the amount of pollution that can be emitted from different kinds of vehicles, and has made those emissions standards more stringent over time. The Congress also decided to preclude states from setting emissions requirements for cars, in an effort to achieve national uniformity. As a result, California (which already had a mobile source program in place when Congress first acted) is the only state that can adopt more stringent vehicle emission standards than those set by EPA. After a 7-year legal battle over whether the state could impose stricter standards than mandated under the Act, the EPA announced on June 30, 2009 that it will give California the waiver it needs to begin regulating greenhouse gas emissions from cars and trucks. The U.S. Chamber of Commerce and the National Automobile Dealers Association filed a petition challenging this waiver, and the matter is currently pending.In an April 2007 decision in Massachusetts v. Environmental Protection Agency, No. 05-1120, (U.S. Apr. 2, 2007) the U.S. Supreme Court decided that:
New Source Review (NSR)Much of the CAA is focused on ensuring that major new sources of pollution, such as factories, install modern pollution controls at the time of construction. The Congress anticipated that as older stationary sources were enlarged or improved with significant modifications, they too would install pollution controls at that time. In 2003, the EPA issued complex rules that described when a modification at one of these older sources qualifies as "major" and therefore requires the source's owner to install modern pollution controls at the same time. These new rules defined "routine maintenance" as any activity that amounts to less than 20 percent of a plant's value and allowed power plants and other industrial polluters to modernize their plants without installing new pollution technology. In March 2006, a federal appeals court finally blocked the new rule at the request of 14 states that contended that the changes were illegal and could increase the amount of health-threatening pollution in the atmosphere. More recently, Judge Thomas Varlan of the U.S. District Court for the Eastern District of Tennessee found in favor of the Tennessee Valley Authority in a lawsuit in which environmental groups accused the utility of violating the NSR permitting program by not installing new controls when upgrading its facility. Judge Varlan ruled that 1988 upgrades at the TVA's Bull Run plant in Clinton, Tennessee constituted "routine maintenance, repair and replacement" and were therefore exempted from NSR requirements.
Supreme Court Decides NSR issues
In April 2007, the U.S. Supreme Court sided with environmental groups in Environmental Defense v. Duke Energy Corp. The case allows EPA to continue to regulate renovated power plants as "new sources" based on the total amount of pollution they emit, rather than based on the rate at which they emit it. This is important for air quality, as plant renovations often expand the operating time for plants. Increased hours of operation could lead to large increases in pollution if EPA were to use the hourly-rate standard desired by industry to trigger NSR rules and plants were not, consequently, required to reduce their rate of emission when they modify their plants to operate for longer periods of time. Another issue related to NSR arises from "fugitive emissions"--such as dust from mining operations or chemicals leaking from pipelines in the course of production. In 2002, the EPA issued an NSR rule that required the inclusion of such fugitive emissions in computing a source's emissions to determine whether NSR rules apply to a proposed facility modification. The EPA changed the rule in December 2008, but the Natural Resources Defense Council petitioned the agency to reconsider the rule change in February 2009. In April 2009, the EPA announced plans to reconsider the Bush-era NSR regulations, and in March 2010, the agency announced that it would delay the rule until October 3, 2011. In September 2009, the Obama Administration announced plans to scrap the previous administration's guidance on NSR for oil and gas operations, opening the door for environmental challenges to oil and gas fields with multiple sources of emissions. In December 2009, the EPA announced plans to review its new source performance standards for oil and gas operations, in response to a lawsuit filed by environmental groups. In late March 2010 the agency announced that it will accept comments on its proposal but that its "preferred option is to revoke the NSR aggregation amendments." The EPA also proposed to extend the effective date of the aggregation policy to 11/18/10 to give the agency time to complete the reconsideration. For more information on these court actions as well as other related cases on new source review go to EPA's web page. A report by the National Research Council on New Source Review for Stationary Sources of Air Pollution may be purchased or viewed on-line. For additional information on fugitive emissions from oil and natural gas activities, review the Natural Resources Law Center's Intermountain West Oil and Gas BMP Project website. PermitsThe CAA requires all major stationary sources of pollution (such as factories, power plants, smelters, refineries) to secure an air quality permit from the state agency (if it has an approved air quality program), a tribal agency, or the EPA. Those permits are open for public examination. In addition, these sources are required to monitor their emissions to assure they are complying with the air quality permits. That information also is available for examination by the public.For a time, the EPA had a policy of suspending normal emission standards for large sources holding Clean Air Act Title V permits during periods of "startup, shutdown, and malfunction" (SSM). Environmentalists objected that the SSM exemption was applied inappropriately to periods of normal operation, and the U.S. District Court for the D.C. Circuit agreed in 2008, in the case American Chemistry Council v. Sierra Club. On March 8, 2010, the U.S. Supreme Court declined to review the D.C. Circuit Court's ruling that prohibited the EPA from suspending normal emissions standards for major pollutions ources during SSM periods. For more information on air permits, go to EPA's web page. Citizen SuitsIf a citizen or a citizen group believes a pollution source is violating its permit, that group or individual can ask a federal court to stop those pollution violations and even to award monetary damages. For example, citizen groups who believe that old coal-fired power plants have modified their facilities without getting a required permit are suing in several parts of the country to force those power plants to install modern emissions controls. And, early in 2010, environmental groups filed a notice of intent to sue the EPA for failing to meet deadlines to limit pollutants in several western states. See "Idaho, four other western states named in EPA lawsuit," Idaho Statesman, 2/1/10.Process Essentials: Protecting Clean Air AreasIn major amendments to the CAA in 1977, the Congress took note of the fact that many areas of the country -- especially in the West -- have clean air. In response, the Congress added several provisions that are designed to keep air quality in these areas from deteriorating, especially in places like national parks.Class 1, 2 and 3 AreasIn the 1977 CAA amendments, the Congress decided to classify all those areas that meet or exceed the nationally applicable air quality standards as either class 1, class 2, or class 3. Based on the area's classification, EPA and states can permit certain amounts of increased pollution. The difference between a preexisting level of pollution and a new level is called an "increment." The Congress decided that most national parks and wilderness areas that were already in existence at the time of the 1977 amendments would be designated as class 1 areas, where only a small increase in pollution levels could be permitted. The legislation designated the rest of the clean air areas as class 2, where some additional pollution could occur. In addition, Congress allowed states to designate some areas as class 3, where the most pollution would be allowed, but still not enough to cause a violation of the national air quality standards. However, no states have redesignated a class 2 area as class 3.For a list of federal class 1 areas in your state, see the EPA website.
Prevention of Significant DeteriorationWhen a major new factory or other pollution source is proposed to be constructed, the state air quality agency must assess whether that new source's pollution would cause a degradation of air quality in a class 1 area, or cause the added pollution to exceed the increment allowed for the designated class. If the state agency concludes that a new source would adversely affect air quality related values in a national park or wilderness area, or exceed the allowable "increment," then the agency will require the new source to install more efficient emissions control equipment.Visibility ProtectionIn the 1977 amendments, the Congress also established a program to reduce visibility impairment that was being observed in national parks and wilderness areas like the Grand Canyon. The Congress asked EPA to address both "plumes" that could relatively easily be traced from one or a few sources to a national park or wilderness area as well as the soup of pollutants that came from many, many sources and is transported over long distances (known as regional haze). Using these provisions, EPA was able to leverage a very large coal-fired power plant in Arizona to install pollution controls to help reduce visibility impairment in the Grand Canyon.Best Available Retrofit Technology (BART)If EPA or a citizen group thinks a large source of pollution is directly affecting a class 1 area (a national park or wilderness area that was in existence in August 1977), and can convince the source to voluntarily reduce its emissions, or a federal court to require the source to clean up its emissions, the source likely will be required to install emissions controls that are described as best Available Retrofit Technology, or BART. When applying BART, EPA can consider a number of factors that bear on the feasibility and effectiveness of different pollution control technologies, including costs and environmental impacts of compliance and the remaining useful life of the source.Regional HazeRegional haze can obscure visibility in a national park (e.g., the view from an overlook at Canyonlands), but it is attributable to many, many sources, some of them hundreds of miles away. It is really a "soup" of pollutants. While the 1977 amendments to the CAA asked the EPA to deal with the problem of regional haze, for a number of years the agency did little because it felt the science was inconclusive. In the 1990 amendments to the CAA, the Congress again asked EPA to tackle the issue of regional haze and established a Grand Canyon Visibility Transport Commission to evaluate the regional haze problem in the American Southwest. That commission, which was chaired by governors and tribal leaders and included all stakeholders, recommended a number of control measures, including a cap on emissions of sulfur dioxide from power plants and other sources, as a way to protect air quality in class 1 areas. That program's success is now being used as a model in other parts of the country for dealing with regional haze at national parks and wilderness areas.
A copy of the Grand Canyon Visibility Transport Commission report is available from the Western Governor's Association web site. In a Federal Register notice dated January 9, 2009, the EPA reported that more than three dozen states have failed to submit adequate plans to reduce regional haze affecting national parks and wilderness areas. These plans were supposed to be submitted by December 17, 2007, but the EPA did not take action to enforce the deadline until sued by environmental groups. Five states submitted adequate plans: Arizona, Colorado, Michigan, New Mexico, and Wyoming. In June, 2009, environmental groups petitioned the U.S. Department of the Interior to certify that the nitrogen dioxide emissions from a coal-fired power plant in Washington state is causing haze and impairing visibility in Mt. Ranier and Olympic national parks, a move aimed at forcing tighter pollution controls on the plant. In March 2010, environmental groups urged the EPA to substantially toughen its smog standards to protect national parks as part of the administration's proposal to tighten its health-based "primary" standard for ozone, or smog, and adopt a new "secondary" standard aimed at protecting vegetation and ecosystems. Sixteen groups wrote EPA a letter on May 20, 2010, asking the agency to establish regional haze plans “that provide the full degree of visibility protection for Class I areas as required by law,” and focusing especially on the 25 states that have not yet submitted plans. For more information on the environmental groups' action, see the National Parks Conservation Association's press release. ControversiesEnergy Development in the Powder River BasinIn late May 2004, several conservation organizations filed a lawsuit in federal court alleging that the Bureau of Land Management had failed to adequately evaluate the cumulative effect of emissions from coalbed methane wells, coal mines and coal-fired power plants, and other sources on national parks and wilderness areas in the Powder River Basin region. The conservationists allege that these emissions are degrading air quality in those class 1 areas. This lawsuit is the first time critics of oil and gas production in the basin have used air pollution issues as their primary argument in a lawsuit. The conservation organizations contend that the EIS process failed to consider all the coalbed methane wells that are projected for the area as well as emissions from several large surface mines in Wyoming.Western Coal at the CrossroadsPower Plant MercuryIn February 2008, the U.S. Court of Appeals for the District of Columbia vacated two key rules issued by the Bush Administration on the regulation of mercury emissions from power plants (State of New Jersey v. EPA). One rule tried to remove coal and oil-fired power plants from strict CAA controls on mercury; the other had set the stage for a controversial cap and trade program for mercury. As described in Western Coal at the Crossroads, western coal production is an important part of the economies of many western states. In this report, Western Resource Advocates (WRA) argues that the preeminent energy challenge facing the Interior West is to meet growing energy demands in a way that protects the region's natural environment while maintaining a vibrant, productive economy. Coal's large role in the West's energy system has come with a high environmental price tag - consumption of large amounts of water, and emission of vast quantities of air pollution and global warming pollution. WRA's report argues that developing integrated gasification combined cycle power plants using western coal is essential if the region's coal resources are to play a role in meeting the West's electricity needs and continue to provide fuel for coal power plants outside the region. In July 2010, the Environmental Protection Agency announced new air quality rules for coal-burning power plants, replacing a plan enacted by the Bush administration but thrown out as inadequate in 2008. The proposed rules will require utilities operating coal-burning plants to install scrubbers and other technology to reduce emissions of sulfur dioxide and nitrous oxides, which react in the atmosphere to form fine particles (soot) and ground-level ozone (smog). Greenhouse Gas EmissionsPresident Obama's administration is pursuing a markedly different direction than the prior administration on federal regulation of the gases that contribute to global warming. For example, the EPA reversed position and granted California a waiver to regulate greenhouse gas emissions from automobiles. The U.S. Chamber of Commerce and the National Automobile Dealers Association filed a petition to overturn this decision, and the case is currently pending. |
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Links
Public Laws
Clean Air Act as amended in 1990 (CAA)42 U.S.C. sections 7401 to 7671q.
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Regulations
EPA regulations related to the CAA(40 CFR Part 50 through 97 ) are available from the EPA web site.
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GPO Access
The regulations are also available from GPO Access.
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Environmental Protection Agency
EPA's air quality home pageThe EPA's web site provides a variety of data, maps and information about air quality and the CAA.
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Plain English Guide
EPA's primer on the CAA
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Other Resources
SaveTheCleanAirAct.orgThe Save The Clean Air Act web site is a project of SaveOurEnvironment.org -- a collaborative effort of the nation's most influential environmental advocacy organizations harnessing the power of the internet to increase public awareness and activism on today's most important environmental issues. Their web site on clean air includes recent news articles, their own analysis of proposals and current policy, and calls for action.
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Grand Canyon Trust
The Grand Canyon Trust is an organization dedicated to protecting and restoring the canyon country of the Colorado Plateau. The organization's web site includes information on the Western Regional Air Partnership and some of the major power plants of the area.
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