Clean Air Act (United States)
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Long title | Clean Air Act of 1963 |
---|---|
Acronyms (colloquial) | CAA |
Effective | Dec. 17, 1963 |
Citations | |
Public law | P.L. 88-206 |
Statutes at Large | 77 Stat. 392 |
Codification | |
Titles amended | 42 |
U.S.C. sections created | 7401 |
Major amendments | |
Air Quality Act of 1967 (81 Stat. 485, P.L. 90-148) Clean Air Act Extension of 1970 (84 Stat. 1676, P.L. 91-604 Clean Air Act Amendments of 1977 (91 Stat. 685, P.L. 95-95) Clean Air Act Amendments of 1990 (104 Stat. 2468, P.L. 101-549) | |
United States Supreme Court cases | |
Union Elec. Co. v. EPA, 427 U.S. 246 (1976) Chevron USA v. Natural Resources Defense Council, 467 U.S. 837 (1984). |
The Clean Air Act is a United States federal law designed to control air pollution on a national level. It requires the Environmental Protection Agency (EPA) to develop and enforce regulations to protect the general public from exposure to airborne contaminants that are known to be hazardous to human health. The 1963 Act established a basic research program, which was expanded in 1967. The major amendments to the law, requiring regulatory controls for air pollution, were enacted in 1970, 1977 and 1990.
The 1970 amendments greatly expanded the federal mandate by requiring comprehensive federal and state regulations for both stationary (industrial) pollution sources and mobile sources. Federal enforcement authority was also significantly expanded.
The 1990 amendments added provisions for addressing acid rain, ozone depletion and toxic air pollution, established a national permits program for stationary sources, and increased enforcement authority. The amendments also established new auto gasoline reformulation requirements, set Reid Vapor Pressure (RVP) standards to control evaporative emissions from gasoline, and mandated that the new gasoline formulations be sold from May to September in many states.
The Clean Air Act is significant in that it was the first major environmental law in the United States to include a provision for citizen suits. Numerous state and local governments have enacted similar legislation, either implementing federal programs or filling in locally important gaps in federal programs.
Components of Air Pollution Prevention and Control
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Title I - Programs and Activities
Part A - Air Quality and Emissions Limitations
This section of the act states the Congressional Findings and Declaration Of Purpose which include protecting and enhancing the Nation's air quality to promote public health. The declaration also encourages the development of regional air pollution prevention and control programs along with providing technical and financial assistance to State and local governments for the execution of air pollution prevention. Additional sub chapters consist of cooperative activities, research, investigation, training and other activities, as well as research relating to fuels and vehicles. Cite error: The <ref>
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Part B - Ozone Protection
In light of advancements in understanding of atmospheric chemistry, this section was replaced by Title VI in 1990.[1]
These changes reflect a significant change in scientific understanding about how ozone is formed and depleted. Specifically, ozone's absorption spectrum covers UVC light and shorter wave UVB, letting through UVA (which is largely harmless to people). Ozone exists in the stratosphere, not the troposphere, exhibiting a lateral distribution because it is destroyed by strong sunlight; there is more at the poles. Ozone is made naturally when O2 comes in contact with photons from solar radiation. Therefore a decrease in the intensity of solar radiation also results in a decrease in the formation of ozone in the stratosphere. This exchange is known as the Chapman mechanism:
- O2 + UV photon → 2 O (note that atmospheric oxygen as O is highly unstable)
- O + O2 + M → O3 (O3 is Ozone) + M
where M represents a third molecule necessary to carry off the excess energy of the collision of O + O2. Depletion of Ozone occurs in the presence of Freon and chlorofluorocarbons (CFCs). Following discovery of the Ozone hole in 1974, the 1987 Montreal Protocol was successful in implementing a plan to replace CFCs. The speed and cooperation of the Montreal Protocol is viewed by some environmentalists as an example of what is possible for the future of environmental issues, if the political will can be garnered.
Part C - Prevention of Significant Deterioration of Air Quality
Major stationary sources of air pollution and certain modifications to those sources are required by the Act to obtain an air permit before commencing construction. This permitting process is known as New Source Review (NSR). The NSR program applies to sources that are located in areas that meet National Ambient Air Quality Standards ("attainment areas"), sources in areas that do not meet the NAAQS (nonattainment areas), and areas that are unclassifiable with respect to the NAAQS. Permits for sources in attainment or unclassifiable areas are referred to as Prevention of Significant Deterioration (PSD) of air quality permits, while permits for sources located in nonattainment areas are referred to as nonattainment area (NAA) permits.[2] The fundamental goals of the PSD program are to:
- prevent the development of new nonattainment areas by ensuring that economic growth occurs in harmony with the preservation of existing clean air resources;
- protect public health and welfare from any adverse effects which might occur even in areas with air quality that meets the NAAQS; and
- preserve and enhance the air quality in national parks and other areas of special natural recreational, scenic, or historic value.[3]
Part D - Plan Requirements for Nonattainment Areas
If an area is considered a nonattainment area, the state is required to submit a plan to reach an attainment status for that area as soon as possible but no later than five years. The classification of the nonattainment area is based on the severity of the air and how easy it will be to obtain cleaner air.
The plan must include:
- reasonable further progress
- an inventory of all pollutants that do not meet standards
- a permit for the use of any resource
- other control measures, means, and techniques used to reach standard qualifications
- contingency measures
The plan must be sent to an administrator for approval and then revised to the administrator’s requirements. The plan shall also include which level of authority, the local government or the state, will implement and enforce the various changes. Once an area has achieved attainment status, a request must be made for reevaluation. In this request a plan for maintenance of air quality must be included.
Title II - Emission Standards for Moving Sources
Part A - Motor Vehicle Emission and Fuel Standards (CAA § 201-219; USC § 7521-7554)
This part of the bill was extremely contentious at the time it was passed. The automobile industry argued that they could not meet the new standards and Senators expressed concern about the impact of this part of the legislation, in particular, on the economy. Specific new emissions standards for moving sources passed years later. Jevons paradox has done away with much of the system-gains in automobile efficiency since then. {{citation}}
: Empty citation (help) Because cars are more efficient, driving is less costly, so people now drive more on average, and this increased driving has overwhelmed the energy savings gained by the initial improvements in fuel efficiency. This same problem may be observed in the broader commercial sense when things are made more efficiently, driving down costs, so more units are sold, so that incremental improvements are overcome. This is what is so often lauded as improving profits and quality of life, but is environmentally damaging. Meanwhile, the focus is usually on the success of the solution, so drumming up further political support for the issue may be difficult. If individuals, corporations, and nations can externalize their costs, they will.
Part B - Aircraft Emission Standards
Numerous amounts of Volatile Organic compounds (VOC's) are emitted in the air over airports and affect the air quality in the region. VOC's include hazardous emissions of compounds such as benzene, formaldehyde, and butadienes which are known to cause health problems such as birth defects, cancer, and skin irritation. Hundreds of tons of emissions from air crafts, ground support equipment, heating systems, and shuttles and passenger vehicles are released into the air causing smog. Therefore, major cities such as Seattle, Denver, and San Fransisco are requiring Climate Action Plan as well as a greenhouse gas inventory. Additionally, federal programs such as VALE are working to offset costs for programs that reduce emissions. [4]
Under Title II, the EPA declares certain emission standards for airlines and aircraft engines and has adopted some standards set by the International Civil Aviation Organization (ICAO). However, the standards for aircraft emissions of carbon dioxide are uncertain and have not been established by either ICAO nor EPA. [5] . As for regulations to insure compliance with standards, it is the responsibility of the Secretary of Transportation, after consultation with the Administrator, to prescribe regulations that comply with section 7571. In addition, the Secretary will also insure that that the necessary inspections are accomplished. It is also stated that no state or political subdivision can adopt or attempt to enforce any standard respecting emissions of any air pollutant from any aircraft or engine unless it is identical to a standard applicable to an aircraft [6] .
Part C - Clean Fuel Vehicles
Trucks and automobiles play a vital role in harming the air quality. Harmful chemicals such as nitrogen oxide, hydrocarbons, carbon dioxide, and sulfur dioxide are released from motor vehicles, some of which also react with sunlight to produce photochemicals.[7]. These harmful substances change the climate, alter ocean pH and include toxins that may cause cancer, birth defects, and respiratory illness. Various industries are trying to improve the air quality by developing new technologies that reduce emissions.
During the 1990s, there was an increase in the emissions produced by motor vehicles since numerous households (approximately 58 percent) owned two or more vehicles [7]. However, the Clean Fuel Vehicle programs focused on utilizing alternative fuels as well as petroleum based fuels that must meet low emission vehicle (LEV) levels. Compressed natural gas, ethanol, methanol, liquefied petroleum gas, and electricity are some examples of cleaner alternative fuel. Programs such as the California Clean Fuels Program and the Pilot Program are demanding that new fuels need to be developed to reduce harmful emissions.[7]
Title III - General Provisions
EPA developed regulations of a list of categorized sources that emitted any number of the 188 hazardous air pollutants (HAPs), as directed by the 1990 amendments. There are currently 174 categories with plans for the creation of emission standards. Both the new and current sources’ standards are based on “maximum achievable control technology” (MACT), which is defined as control technology being able to reduce the emission of HAPs as much as possible while taking into account the cost and other factors.
Under the law prior to 1990, EPA was required to construct a list of HAPs as while as health-based standards for each one. There were 188 air pollutants listed and the source from which they came. The EPA was given a ten-year time frame to generate technology-based emission standards. Title III is considered a second phase which allows the EPA to assess lingering risk after the enactment of the first phase of emission standards. It is also to enact new standards with regard to the protection of public health.[8]
Title IV - Noise Pollution
This title pre-dates the Clean Air Act. It was originally enacted by Act of July 14, 1955, c. 360. With the passage of the Clean Air Act, it became codified as Title IV. However, another Title IV was enacted in the 1970 amendments. The second Title IV was then appended to this Title IV as Title IV-A (see below).
This title established the EPA Office of Noise Abatement and Control to reduce noise pollution in urban areas, to minimize noise-related impacts on psychological and physiological effects on humans, effects on wildlife and property (including values) and other noise-related issues.
Title IV-A - Acid Deposition Control
This title was added as part of the 1990 amendments. It addresses the issue of acid rain, which is caused by nitrogen oxides (NOX) and sulfur dioxide (SO2) emissions resulting from electric power plants powered by fossil fuels. It also addresses other industrial sources. Originally the method for regulating industrial emissions was very controlled, meaning there was a way to decrease the pollution by a certain amount with a particular type of technology. The 1990 amendments gave industries more options including switching to low-sulfur coal and/or adding devices that controlled the harmful emissions. In some cases plants had to be closed down to prevent the dangerous chemicals from entering the atmosphere.[9]
In order to reduce SO2 emissions, two steps were enacted. The first stage of process required over 100 electric generating facilities larger than 100 megawatts to meet a 3.5 million ton SO2 emission reduction by January 1995. The second stage pertained to facilities larger than 75 megawatts that were given a January 2000 deadline.[9]
Title V - Permits
A national operating permit program, covering thousands of large industrial and commercial sources, was authorized by the 1990 amendments.[10] The permits streamlined the stationary source program by consolidating all applicable requirements for a facility into a single document. Permits are required for large businesses to address what sort of pollutants will be released into the air. The business must also measure the quantity of the pollutants and have a plan to be able to control and minimize the pollution. Businesses must send progress reports to the Administrator every so often. [11] A fee is required to purchase a permit.
Furthermore, in non attainment areas, permit requirements include sources that emit as little as 50, 25, or 10 tons per year of VOC's. This depends on the severity of the region’s non attainment status, whether it is serious, severe, or extreme [12]
Most permits are issued by state and local agencies.[13] If the state does not adequately monitor the requirements, the EPA may take control to see that the business is properly qualified for the permit. The public may request to view the permits by contacting the EPA. As for the term of the permit, it is limited to no more than five years and will require renewing [12]
Title VI - Stratospheric Ozone Protection
Starting in 1990, the main purpose of Title VI was for EPA to set up regulations regarding the use and production of chemicals that harm the Earth’s stratospheric ozone layer. This ozone layer protects against harmful ultraviolet B sunlight which has been linked to several medical conditions including cataracts and skin cancer.[14]
The ozone-destroying chemicals have been organized into two groups, Class I and Class II. Class I consists of substances, including chlorofluorocarbons, that have an ozone depletion potential (ODP) (HL) of 0.2 or higher. Class II lists substances, including hydrochlorofluorocarbons, that are known to or may be detrimental to the stratosphere. Both of these groups have programs set up a timeline for when the substances must be phased-out. For example, Class I substances must be phased out no more than seven years after being added to the list and Class II substances no more than ten years.[15]
Another feature of Title VI is to establish methods for preventing harmful chemicals from entering into the stratosphere in the first place. Some of these methods include recycling or proper disposal of chemicals and finding substitutes that cause less damage if any at all.[15]
Along with the United States there were over 190 countries that signed the Montreal Protocol in 1987. The document states that the countries agree to work on eliminating or limiting the use of any chemical that has ozone destroying properties.[14]
History
Legislation
Congress passed the first Clean Air Act in 1963, creating a research and regulatory program in the U.S. Public Health Service.[16] The Act authorized development of emission standards for stationary sources, but not mobile sources.[17]: 211 The 1967 Air Quality Act mandated enforcement of interstate air pollution standards and authorized ambient monitoring studies and stationary source inspections.[18]
In the Clean Air Act Extension of 1970, Congress greatly expanded the federal mandate by requiring comprehensive federal and state regulations for both industrial and mobile sources.[19] The law established four new regulatory programs:
- National Ambient Air Quality Standards (NAAQS). EPA was required to promulgate national standards for six criteria pollutants: carbon monoxide, nitrogen dioxide, sulfur dioxide, particulate matter, hydrocarbons and photochemical oxidants. (Some of the criteria pollutants were revised in subsequent legislation.)[17]: 213 [20]
- State Implementation Plans (SIPs)
- New Source Performance Standards (NSPS); and
- National Emissions Standards for Hazardous Air Pollutants (NESHAPs).
The 1970 law is sometimes called the "Muskie Act" because of the central role Maine Senator Edmund Muskie played in drafting the bill.[21]
The Clean Air Act Amendments of 1977 required Prevention of Significant Deterioration (PSD) of air quality for areas attaining the NAAQS, and added requirements for non-attainment areas.[22]
The 1990 Clean Air Act added regulatory programs for control of acid deposition (acid rain) and stationary source operating permits. The amendments moved considerably beyond the original criteria pollutants, expanding the NESHAP program with a list of 189 hazardous air pollutants to be controlled within hundreds of source categories, according to a specific schedule.[23] The NAAQS program was also expanded. Other new provisions covered stratospheric ozone protection, increased enforcement authority, and expanded research programs.[24]
The 1990 Clean Air Act Amendments prevent:[25]
Year 2010 (in cases) | Year 2020 (in cases) | |
---|---|---|
Adult Mortality - particles | 160,000 | 230,000 |
Infant Mortality - particles | 230 | 280 |
Mortality - ozone | 4,300 | 71,000 |
Chronic Bronchitis | 54,000 | 75,000 |
Heart Disease - Acute Myocardial Infarction | 130,000 | 200,000 |
Asthma Exacerbation | 1,700,000 | 2,400,000 |
Emergency Room Visits | 86,000 | 120,000 |
School Loss Days | 3,200,000 | 5,400,000 |
Lost Work Days | 13,000,000 | 17,000,000 |
This chart shows the health benefits of the Clean Air Act programs that reduce levels of fine particles and Ozone.
Regulations
![]() | This section needs expansion with: additional regulations. You can help by adding to it. (June 2011) |
Since the initial establishment of six mandated criteria pollutants (ozone, particulate matter, carbon monoxide, nitrogen oxides, sulfur dioxide, and lead), advancements in testing and monitoring have led to the discovery of many other significant air pollutants.[26]
In 1997 EPA tightened the NAAQS regarding permissible levels of the ground-level ozone that make up smog and the fine airborne particulate matter that makes up soot.[27][28] The decision came after months of public review of the proposed new standards, as well as long and fierce internal discussion within the Clinton administration, leading to the most divisive environmental debate of that decade.[29] The new regulations were challenged in the courts by industry groups as a violation of the U.S. Constitution's nondelegation principle and eventually landed in the U.S. Supreme Court,[28] whose 2001 unanimous ruling in Whitman v. American Trucking Associations, Inc. largely upheld EPA's actions.[30]
Roles of the federal government and states
Although the 1990 Clean Air Act is a federal law covering the entire country, the states do much of the work to carry out the Act. The EPA has allowed the individual states to elect responsibility for compliance with and regulation of the CAA within their own borders in exchange for funding. For example, a state air pollution agency holds a hearing on a permit application by a power or chemical plant or fines a company for violating air pollution limits. However, election is not mandatory and in some cases states have chosen to not accept responsibility for enforcement of the act and force the EPA to assume those duties.
In order to take over compliance with the CAA the states must write and submit a state implementation plan (SIP) to the EPA for approval. A state implementation plan is a collection of the regulations a state will use to clean up polluted areas. The states are obligated to notify the public of these plans, though hearings that offer opportunities to comment, in the development of each state implementation plan. The SIP becomes the state's legal guide for local enforcement of the CAA. For example, Rhode Island law requires compliance with the Federal CAA through the SIP.[31] The SIP delegates permitting and enforcement responsibility to the state Department of Environmental Management (RI-DEM).
The federal law recognizes that states should lead in carrying out the Clean Air Act, because pollution control problems often require special understanding of local industries, geography, housing patterns, etc. However, states are not allowed to have weaker pollution controls than the national minimum criteria set by EPA. EPA must approve each SIP, and if a SIP isn't acceptable, EPA can take over CAA enforcement in that state.
The United States government, through the EPA, assists the states by providing scientific research, expert studies, engineering designs, and money to support clean air programs.
Metropolitan Planning Organizations must approve all federally-funded transportation projects in a given urban area. If the MPO's plans do not, Federal Highway Administration and the Federal Transit Administration have the authority to withhold funds if the plans do not conform with federal requirements, including air quality standards.[32] In 2010, the EPA directly fined the San Joaquin Valley Air Pollution Control District $29 million for failure to meet ozone standards, resulting in fees for county drivers and businesses. This was the results of a federal appeals court case that required the EPA to continue enforce older, stronger standards,[33] and spurred debate in Congress over amending the Act.[34]
Interstate air pollution
Air pollution often travels from its source in one state to another state. In many metropolitan areas, people live in one state and work or shop in another; air pollution from cars and trucks may spread throughout the interstate area. The 1990 Clean Air Act provides for interstate commissions on air pollution control, which are to develop regional strategies for cleaning up air pollution. The 1990 amendments include other provisions to reduce interstate air pollution.
The Acid Rain Program, created under Title IV of the Act, authorizes emissions trading to reduce the overall cost of controlling emissions of sulfur dioxide.
Leak detection and repair
The Act requires industrial facilities to implement a Leak Detection and Repair (LDAR) program to monitor and audit a facility's fugitive emissions of volatile organic compounds (VOC). The program is intended to identify and repair components such as valves, pumps, compressors, flanges, connectors and other components that may be leaking. These components are the main source of the fugitive VOC emissions.
Testing is done manually using a portable vapor analyzer that read in parts per million (ppm). Monitoring frequency, and the leak threshold, is determined by various factors such as the type of component being tested and the chemical running through the line. Moving components such as pumps and agitators are monitored more frequently than non-moving components such as flanges and screwed connectors. The regulations require that when a leak is detected the component be repaired within a set amount of days. Most facilities get 5 days for an initial repair attempt with no more than 15 days for a complete repair. Allowances for delaying the repairs beyond the allowed time are made for some components where repairing the component requires shutting process equipment down.
Application to greenhouse gas emissions
EPA began regulating greenhouse gases (GHGs) from mobile and stationary sources of air pollution under the Clean Air Act for the first time on January 2, 2011. Standards for mobile sources have been established pursuant to Section 202 of the CAA, and GHGs from stationary sources are controlled under the authority of Part C of Title I of the Act. See Regulation of Greenhouse Gases Under the Clean Air Act.
See also
- The Center for Clean Air Policy (in the US)
- Environmental policy of the United States
- Emission standards
- Emissions trading
- Startups, shutdowns, and malfunctions
- Commission on Risk Assessment and Risk Management
- Alan Carlin, controversy over the EPA carbon dioxide endangerment finding
References
- ^ U.S. Environmental Protection Agency (EPA), Washington, DC. "Title VI - Stratospheric Ozone Protection." Updated 2008-12-19.
- ^ U.S. Environmental Protection Agency. (1990). New Source Review Workshop Manual: Prevention of Significant Deterioration and Nonattainment Area Permitting. http://www.epa.gov/ttn/nsr/gen/wkshpman.pdf
- ^ NSR Workshop Manual, p. 3
- ^ Trendowski, John. "Sustainability Trends — Reducing Emissions at Airports" (PDF). Airport Magazine. Retrieved 22 April 2012.
- ^ "Aviation and Climate Change" (PDF). United States Government Accountability Office. Retrieved 22 April 2012.
- ^ "Clean Air Act". Cornell University Law School. Retrieved 22 April 2012.
- ^ a b c "www.biodiesel.org" (PDF). The Clean Air Act's Clean-Fuel Vehicle Program. Retrieved 10 March 2012. Cite error: The named reference "Biodiesel" was defined multiple times with different content (see the help page).
- ^ “Title III: General” Clean Air Act, United States. The Earth Encyclopedia. Updated: Apr 12, 2011. http://www.eoearth.org/article/Clean_Air_Act,_United_States
- ^ a b “ Title IV: Acid Deposition Control.” Clean Air Act, United States. The Earth Encyclopedia. Updated: Apr 12 2011. http://www.eoearth.org/article/Clean_Air_Act,_United_States#gen4
- ^ EPA. "Permits and Enforcement." The Plain English Guide to the Clean Air Act. Revised 2011-11-08.
- ^ EPA. "Permits and Enforcement." The Plain English Guide to the Clean Air Act. Revised 2011-11-08.
- ^ a b McCarthy, James. "Clean Air Act: A Summary of the Act and its Major Requirements" (PDF). CRS Report for Congress. Retrieved 23 April 2012.
- ^ EPA (February 1998). "Air Pollution Operating Permit Program Update: Key Features and Benefits." Document no. EPA/451/K-98/002. p. 1.
- ^ a b EPA. "Protecting the Stratospheric Ozone Layer." The Plain English Guide to the Clean Air Act. Revised 2011-11-08.
- ^ a b “ Title VI: Stratospheric Ozone Protection.” Clean Air Act, United States. The Earth Encyclopedia. Updated: Apr 12 2011. http://www.eoearth.org/article/Clean_Air_Act,_United_States#gen2
- ^ Clean Air Act of 1963, Pub. L. 88–206, 77 Stat. 392, 1963-12-17.
- ^ a b Jacobson, Mark Z. (2002). Atmospheric Pollution: History, Science, and Regulation. Cambridge University Press. ISBN 978-0-521-01044-3.
- ^ EPA. "History of the Clean Air Act." Updated 2010-11-16.
- ^ Clean Air Act Extension of 1970, 84 Stat. 1676, Pub. L. 91–604, 1970-12-31.
- ^ EPA. "National Ambient Air Quality Standards (NAAQS)." Updated 2011-04-18.
- ^ "Muskie Act". Toyota Motor Corp.
- ^ Clean Air Act Amendments of 1977, Pub. L. 95–95, 91 Stat. 685, 1977-08-07.
- ^ EPA. "Reducing Toxic Air Pollutants." The Plain English Guide to the Clean Air Act. Revised 2011-11-08.
- ^ Clean Air Act Amendments of 1990, Pub. L. 101–549, 104 Stat. 2399, 1990-11-15.
- ^ EPA. Second Prospective Study - 1990 to 2020. Environmental Protection Agency. Retrieved from <http://www.epa.gov/air/sect812/prospective2.html>.
- ^ EPA. "What Are the Six Common Air Pollutants?" Revised 2010-07-01.
- ^ Cushman Jr., John H. (June 26, 1997). "Clinton Sharply Tightens Air Pollution Regulations Despite Concern Over Costs". New York Times.
- ^ a b Chebium, Raju (November 7, 2000). "U.S. Supreme Court hears clean air cases regarding smog and soot standards". CNN.
- ^ Cushman Jr., John H. (June 25, 1997). "D'Amato Vows to Fight for E.P.A.'s Tightened Air Standards". New York Times.
- ^ Greenhouse, Linda (2001-02-28). "E.P.A.'s Right to Set Air Rules Wins Supreme Court Backing". New York Times.
- ^ Rhode Island General Law, Title 23, Chapter 23, Section 2 (RIGL 23-23-2).
- ^ http://onlinemanuals.txdot.gov/txdotmanuals/mpo/planning_process_selfcertification.htm
- ^ Nelson, Gabriel (2011-07-01). "D.C. Circuit Rejects EPA's Latest Guidance on Smog Standards". The New York Times.
- ^ http://www.eenews.net/public/EEDaily/2011/05/03/3
- http://www.gao.gov/new.items/d09554.pdf
- http://epa.gov/oar/caa/title2.html#iib
- http://www.cscos.com/pdf/articles/AirportMagazineSustainabilityArticle.pdf
External links
Works related to Clean Air Act at Wikisource
- EPA's The Plain English Guide to the Clean Air Act
- EPA Enforcement and Compliance History Online
- Articles needing cleanup from July 2009
- Cleanup tagged articles without a reason field from July 2009
- Wikipedia pages needing cleanup from July 2009
- Climate change in the United States
- Air pollution in the United States
- United States federal environmental legislation
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- 88th United States Congress
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