State Implementation Plans (SIPS) - 1990 Clean Air Act

The Clean Air Act

The Clean Air Act (CAA), codified as 42 U.S.C. 7401 et seq., seeks to protect human health and the environment from emissions that pollute ambient or outdoor air. To ensure that air quality in all areas of the U.S. meets certain federally mandated minimum standards, it assigns primary responsibility to the States to assure adequate air quality. The Act deems areas not meeting standards as non-attainment, and requires them to implement specified air pollution controls. In addition to provisions relating to ozone non-attainment, the Act addresses mobile sources, air toxics, and the special problem of acid rain. It establishes a comprehensive permit system for all sources. Other provisions address ozone depleting substances, enforcement, clean air research, disadvantaged business concerns, and employment transition and assistance.

Background

Prior to 1955, air pollution was controlled at the State and local level. Federal legislation controlling air pollution was first passed in 1955. The Federal role was strengthened in subsequent amendments and changed significantly with the passage of the Clean Air Act Amendments of 1990 (P.L. 101-549) which was signed into law on November 15, 1990. Significant new provisions added to the Act by the 1990 amendments included (1) the acid rain control program, including the use of marketable allowances for introducing flexibility into the sulfur oxides reduction program; (2) a State-run program requiring permits for the operation of many sources of air pollutants, including a requirement that fees be imposed to cover administrative costs; and (3) the authorization of a 5-year, $250 million program for retraining and unemployment benefits for workers displaced by requirements of the CAA.

Changes to the Act by the 1990 amendments included, in part, provisions to (1) classify areas in non-attainment according to the extent to which they exceed the standard and to tailor deadlines, planning, and controls according to each area's status and problem; (2) tighten automobile emission standards and to require reformulated and alternative fuels in the most-polluted areas; (3) revise the air toxics section, establishing a new program of technology-based standards and addressing the problem of sudden, catastrophic releases of toxics; (4) change the stratospheric ozone protection provision to a phase-out of the most ozone-depleting chemicals; and (5) update the enforcement provisions so they parallel those in other pollution control acts, including authority for EPA to assess administrative penalties.

The following sections describe each of these new and revised programs required by the Act.

National Ambient Air Quality Standards (NAAQS) (Section 109)

The Act requires EPA to establish NAAQS for several types of air pollutants. The NAAQS must be designed to protect public health and welfare within an adequate margin of safety. The NAAQS must be attained as expeditiously as possible, and in no case more than five years after EPA determines that an area does not meet the standards, unless EPA provides an extension of the deadline. For areas not in attainment with NAAQS, the CAA amendments of 1990 established special compliance schedules, staggered according to each area's air pollution problem and status, as described below.

EPA has promulgated NAAQS for six air pollutants (sulfur dioxide (SO₂ ), particulate matter (PM₁₀ ), nitrogen dioxide (NO₂ ), carbon monoxide (CO), ozone (O₃), and lead (Pb)). The Act requires EPA to review scientific data upon which the standards are based, and revise the standards, if necessary, every five years. More often than not, however, EPA has taken more than five years in reviewing and revising the standards.

State Implementation Plans (SIPS) (Section 110)

While the Act authorizes the EPA to set NAAQS, the States are responsible for establishing procedures to attain and maintain the NAAQS. The States adopt plans, known as State Implementation Plans (SIPS), and submit them to EPA to ensure that they are adequate to meet the statutory requirements. Each State is responsible for achieving the NAAQS within its jurisdiction. Areas not meeting NAAQS are called "non-attainment" areas.

SIPs are based on emission inventories and computer models to determine whether air quality violations will occur. If these data show that standards would be exceeded, the State imposes necessary controls on existing sources to ensure that emissions do not cause "exceedances" of the standards. Proposed new and modified sources must obtain State construction permits in which the applicant shows how the anticipated emissions will not exceed allowable limits. In non-attainment areas, emissions from new or modified sources must be offset by reductions in emissions from existing sources.

The 1990 amendments require EPA to impose one of two sanctions in areas which fail to submit a SIP, fail to submit an adequate SIP, or fail to implement a SIP: either a 2-to-1 emissions offset for the construction of new polluting sources, or a ban on Federal highway grants (an additional ban on air quality grants is discretionary).

Non-attainment Requirements (Part D of Title I)

In a major departure from the prior law, the 1900 Clean Air Act Amendments group non-attainment areas into classifications based on the extent to which the NAAQS is exceeded, and establish specific pollution controls and attainment dates for each classification.

Non-attainment areas are classified on the basis of a "design value", which is derived from the pollutant concentration (in parts per million) recorded by air quality monitoring devices. The design value for ozone is the fourth highest reading measured over a 3-year period. The Act creates 5 classes of ozone non-attainment. Only Los Angeles falls into the "extreme" class. A simpler classification system establishes moderate and serious non-attainment areas for carbon monoxide and particulate matter with correspondingly more stringent control requirements for the more polluted class.

For ozone non-attainment areas, the deadlines are established for each classification. For carbon monoxide, the attainment date for moderate areas is December 31, 1995, and for serious areas is December 31, 2000. For particulate matter, the deadline for areas currently designated moderate non-attainment areas was December 31, 1994; for those areas subsequently designated as moderate; the deadline is 6 years after designation. For serious areas, the respective deadlines are December 31, 2001 or 10 years after designation.

Although areas with more severe air pollution problems have a longer time to meet the standards, more stringent control requirements are imposed through the SIP. Each category of non-attainment must have specified air pollution control measures imposed. Marginal ozone non-attainment areas are required to have few controls imposed. Each area must meet the requirements of lower non-attainment categories in addition to the requirements of its own category.

A summary of the primary ozone control requirements for each non-attainment category follows:

• Inventory emissions sources (to be updated every 3 years).
• Require 1.1 to 1 offsets (i.e., industries must reduce emissions from existing facilities by 10 percent more than emissions of any new facility opened in the area).
• Impose reasonable available control technology (RACT) on all major sources emitting more than 100 tons per year for the nine industrial categories where EPA had already issued control technique guidelines describing RACT prior to 1990.

• Meet all requirements for marginal areas.
• Impose a 15 percent reduction in volatile organic compounds (VOCs) in 6 years.
• Adopt a basic vehicle inspection and maintenance program.
• Impose RACT on all major sources emitting more than 100 tons per year for all additional industrial categories where EPA will issue control technique guidelines describing RACT.
• Require vapor recovery at gas stations selling more than 10,000 gallons per month.
• Require 1.15 to 1 offsets.

• Meet all requirements for moderate areas.
• Reduce definition of a major source of VOCs from emissions of 100 tons per year to 50 tons per year for the purpose of imposing RACT.
• Reduce VOCs 3 percent annually for years 7 to 9 after the 15 percent reduction already required by year 6.
• Improve monitoring.
• Adopt an enhanced vehicle inspection and maintenance program.
• Require fleet vehicles to use clean alternative fuels.
• Adopt transportation control measures if the number of vehicle miles travelled in the area is greater than expected.
• Require 1.2 to 1 offsets.
• Adopt contingency measures if the area does not meet required VOC reductions.

• Meet all requirements for serious areas.
• Reduce definition of a major source of VOCs from emissions of 50 tons per year to 25 tons per year for the purpose of imposing RACT.
• Adopt specified transportation control measures.
• Implement a reformulated gasoline program for all vehicles in the area.
• Require 1.3 to 1 offsets.
• Impose $5,000 per ton penalties on major sources if the area does not meet required reductions.

• Meet all requirements for severe areas.
• Reduce definition of a major source of VOCs from emissions of 25 tons per year to 10 tons per year for the purpose of imposing RACT.
• Require clean fuels or advanced control technology for boilers emitting more than 25 tons per year of NO_x.
• Require 1.5 to 1 offsets.

As with ozone non-attainment areas, CO nonattainment areas are subjected to specified control requirements. A summary of the primary CO control requirements for each non-attainment category follows.

• Conduct an inventory of emissions sources.
• Forecast total vehicle miles travelled in the area.
• Adopt an enhanced vehicle inspection and maintenance program.
• Demonstrate annual improvements sufficient to attain the standard.

• Adopt specified transportation control measures.
• Implement a reformulated gasoline program for all vehicles in the area.
• Reduce definition of a major source of CO from emissions of 100 tons per year to 50 tons per year if stationary sources contribute significantly to the CO problem.

Serious areas failing to attain the standard by the deadline have to revise their SIP and demonstrate reductions of 5 percent per year until the standard is attained.

Emission Standards for Mobile Sources (Title II)

The 1990 amendments tightened automobile emission standards. (For cars, the hydrocarbon standard is reduced by 40 percent, the nitrogen oxides standard by 50 percent.) These standards are being phased in over the 1994-1996 model years. If a study due in 1997 shows both the technological feasibility and the need for air quality improvement, yet another round of tightened standards would be imposed in 2004.

The 1990 amendments also require that a cleaner, "reformulated" gasoline be sold, starting in 1995, in the nine worst ozone non-attainment areas (Los Angeles, San Diego, Houston, Baltimore, Philadelphia, New York, Hartford, Chicago, and Milwaukee). Other ozone non-attainment areas will be able to opt in to the reformulated gasoline program at a later date.

Use of alternative fuels other than gasoline will be stimulated by two programs. First, California is required to develop a program requiring low emission vehicles (LEVs) and ultralow emission vehicles (ULEVs) for use in the State to be introduced starting in 1996 at 150,000 vehicles per year and rising to 300,000 vehicles per year in 1999. Second, in all of the most seriously polluted ozone non-attainment areas and the worst CO non-attainment areas, centrally fueled fleets of 10 or more vehicles must purchase some "clean fuel vehicles" when they add new vehicles to existing fleets starting in 1998. The percentage of any new vehicles purchased that must be clean fuel vehicles is 30 percent in 1998, 50 percent in 1999, and 70 percent in 2000. The "clean fuel" vehicles must be the same as those sold in California.

The 1990 amendments also imposed tighter requirements on certification (an auto's useful life is defined as 100,000 miles instead of the earlier 50,000 miles), on emissions allowed during refueling, on low temperature CO emissions, on in-use performance over time, and on warranties for the most expensive emission control components (8 years/80,000 miles for the catalytic converter, electronic emissions control unit, and onboard emissions diagnostic unit). Regulations were also extended to include nonroad fuels and engines.

Hazardous Air Pollutants (Section 112)

Completely rewritten by the CAA Amendments of 1990, section 112 of the Act establishes programs for protecting the public health and environment from exposure to toxic air pollutants. Revised section 112 contains four major provision: Maximum Achievable Control Technology (MACT) requirements, health-based standards, standards for stationary area sources, and requirements for the prevention of catastrophic releases.

First, EPA is to establish technology-based emission standards, called MACT standards, for sources of 189 pollutants listed in the legislation, and to specify categories of sources subject to the emission standards. EPA is to revise the standards periodically (at least every eight years). EPA can, on its initiative or in response to a petition, add or delete substances or source categories from the lists. Section 112 establishes a presumption in favor of regulation for the designated chemicals; it requires regulation of a designated pollutant unless EPA or a petitioner is able to show "that there is adequate data on the health and environmental effects of the substance to determine that emissions, ambient concentrations, bioaccumulation or deposition of the substance may not reasonably be anticipated to cause any adverse effects to human health or adverse environmental effects."

Section 112 requires EPA to set standards for sources of the listed pollutants that achieve "the maximum degree of reduction in emissions" taking into account cost and other non-air-quality factors. The standards for new sources "shall not be less stringent than the most stringent emissions level that is achieved in practice by the best controlled similar source." The standards for existing sources may be less stringent than those for new sources, but must be more stringent than the emission limitations achieved by either the best performing 12 percent of existing sources (if there are more than 30 such sources in the category or subcategory) or the best performing 5 similar sources (if there are fewer than 30). Existing sources are given 3 years following promulgation of standards to achieve compliance, with the possible 1-year extension; additional extensions may be available for special circumstances or for certain categories of sources. Existing sources that achieve voluntary early emissions reductions will receive a 6-year extension for compliance with MACT.

For solid waste incinerators, EPA is to establish performance standards for compliance with both hazardous air pollutant provisions (section 112) and the new source performance requirements (section 111) of the Act. However, rules for both small and large incinerators are overdue.

The second major provision of section 112 sets health-based standards to address situations in which a significant residual risk of adverse health effects or a threat of adverse environmental effects remains after installation of MACT. This provision requires that EPA, after consultation with the Surgeon General of the United States, submit a report to Congress on the public health significance of residual risks, and make recommendations as to legislation regarding such risks. If Congress does not legislate in response to EPA's recommendations, then EPA is required to issue standards for categories of sources of hazardous air pollutants as necessary to protect the public health with an ample margin of safety or to prevent an adverse environmental effect. A residual risk standard is required for any source emitting a cancer-causing pollutant that poses an added risk to the most exposed person of more than 1-in-a-million. Residual risk standards would be due 8 years after promulgation of MACT for the affected source category. Existing sources have 90 days to comply with a residual risk standard, with a possible 2-year extension. In general, residual risk standards do not apply to area sources.

This provison also directs EPA to contract with the National Academy of Sciences for a study of risk assessment methodology, and creates a Risk Assessment and Management Commission to investigate policy implications and appropriate uses of risk assessment and risk management. These studies are designed to ensure that regulatory decisions are well based technically.

Third, in addition to the technology-based and health-based programs for major sources of hazardous air pollution, EPA is to establish standards for stationary "area sources" determined to present a threat of adverse effect to human health or the environment. (Area sources are numerous, small sources such as gas stations or dry cleaners that may cumulatively produce significant quantities of a pollutant.) The provision requires EPA to regualte the stationary area sources responsible for 90 percent of the emissions of the 30 hazardous air pollutants that present the greatest risk to public health in the largest number of urban areas. EPA is to list the sources and pollutants within 5 years of enactment, and promulgate regulations within 10 years. In setting the standard, EPA can impose less stringent "generally available" control technologies, rather than MACT.

Finally, section 112 addresses prevention of sudden, catastrophic releases of air toxics by establishing an independent Chemical Safety and Hazard Investigation Board. The Board wil investigate accidents involving releases of hazardous substances, and conduct studies and prepare reports on the handling of toxic materials, as well as measures to reduce the risk of accidents.

EPA is also authorized to issue prevention, detection, and correction requirements for catastrophic releases of air toxics, which shall require owners and operators to prepare risk management plans for the listed chemicals, including a hazard assessment, measures to prevent releases, and a response program. EPA was to issue these regulations by November 1993, which become effective 3 years after promulgation (or after a substance is listed, whichever is later).

New Source Performance Standards (NSPS) (Section 111)

NSPS establish nationally uniform, technology-based standards for categories of new industrial facilities. These standards accomplish two goals: first, they establish a consistent baseline for pollution control that competing firms must meet, and thereby remove any incentive for States or communities to weaken air pollution standards in order to attract polluting industry; and second they preserve clean air to accomodate future growth, as well as for its own benefits.

NSPS establish maximum emission levels for new or extensively modified major stationary sources -- powerplants, steel mills, and smelters -- with the emission levels determined by the best "adequately demonstrated" continuous control technology available, taking costs into account. EPA must regularly revise and update NSPS applicable to designated sources as new technology becomes available, since the goal is to prevent new pollution problems from developing and to force the installation of new control technology.

Prevention of Significant Deterioration (PSD) (Title I, Part C)

Prevention of Significant Deterioration reflects the principle that areas where the air quality is better than required by NAAQS should be protected from significant new air pollution even if NAAQS would not be violated. The Act divides clean air areas in three classes, and specified the increments of SO 2 and particulate pollution allowed in each. Class I areas include international and national parks, wilderness areas, or other such pristine areas; allowable increments of new pollution are very small. Class II areas include all attainment and not classifiable areas, not designated as Class I; allowable increments of new pollution are modest. Class III represents selected areas that States designate for development; allowable increments of new pollution are large (but not exceeding NAAQS).

Polluting sources in PSD areas must install best available control technology (BACT) that may be more strict than that required by NSPS. The justifications of the policy are that it protects air quality, provides an added margin of health protection, preserves clean air for future development, and prevents firms from gaining a competitive edge by "shopping" for "clean air" to pollute.

Acid Deposition Control (Title IV)

The Clean Air Act Amendments of 1990 added an acid deposition control program to the Act. It sets goals for the year 2000 of reducing annual SO 2 emissions by 10 million tons from 1980 levels and reducing annual NO x emissions by 2 million tons, also from 1980 levels.

The SO 2 reductions are imposed in two steps. Under Phase 1, owners/operators of 111 facilities listed in the law that are larger than 100 megawatts must meet tonnage emission limitations by January 1, 1995. This would reduce SO 2 emission by about 3.5 million tons. Phase 2 would include facilities larger than 75 megawatts.

To introduce some flexibility in the distribution and timing of reductions, the Act creates a comprehensive permit and emissions allowance system. An allowance is a limited authorization to emit a ton of SO 2 . Issued by EPA, the allowances would be allocated to Phase 1 and Phase 2 units in accordance with baseline emissions estimates. Powerplants which commence operation after November 15, 1990 would not receive any allowances. These new units would have to obtain allowances (offsets) from holders of existing allowances. Allowances may be traded nationally during either phase. The law also permits industrial sources and powerplants to sell allowances to utility systems under regulations to be developed by EPA. Allowances may be banked by a utility for future use or sale.

The Act provided for two types of sales to improve the liquidity of the allowance system and to ensure the availability of allowances for utilities and independent power produces who need them. First, a special reserve fund consisting of 2.8 percent of Phase 1 and Phase 2 allowance allocations has been set aside for sale. Allowances from this fund (25,000 annually from 1993-1999 and 50,000 thereafter) are sold at a fixed price fo $1,500 an allowance. Independent power producers have guaranteed rights to these allowances under certain conditions. Second, an annual, open auction sells allowances (150,000 from 1993-1995, and 250,000 from 1996-1999) with no minimum price. Utilities with excess allowances may have them auctioned off at this auction, and any person may buy allowances.

The Act essentially caps SO 2 emissions at individual existing sources through a tonnage limitation, and at future plants through the allowance system. First, emissions from most existing sources are capped at a specified emission rate times an historic baseline level. Second, for plants commencing operation after November 15, 1990, emission must be completely offset with additional reductions at existing facilities beginning after Phase 2 compliance. However, as noted above, the law provides some allowances to future powerplants which meet certain criteria. The utility SO 2 emission cap is set at 8.9 million tons, with some exceptions.

The Act provides that if an affected unit does not have sufficient allowance to cover its emissions, it is subject to an excess emission penalty of $2,000 per ton of SO 2 and required to reduce an additional ton of SO 2 of pollution the next year for each ton of excess pollutant emitted.

The Act also requires EPA to inventory industrial emissions of SO 2 and to report every 5 years, beginning in 1995. If the inventory shows that industrial emissions may reach levels above 5.60 million tons per year, then EPA is to take action under the Act to ensure that the 5.60 million ton cap is not exceeded.

The Act requires EPA to set specific NO x emission rate limitations -- 0.45 lb. per million Btu for tangentially fired boilers and 0.50 lb. per million Btu for wall-fired boilers -- unless those rates cannot be achieved by low-NO x burner technology. Tangentially and wall-fired boilers affected by Phase 1 SO 2 controls must also meet NO x requirements. EPA is to set emission limitations for other types of boilers by 1997 based on low-NO x burner costs. In addition, EPA is to propose and promulgate a revised new source performance standard for NO x from fossil fuel steam generating units.

Permits (Title V)

The Clean Air Act Amendments of 1990 added a Title V to the Act which requires States to administer a comprehensive permit program for the operation of sources emitting air pollutants. These requirements are modeled after similar provisions in the Clean Water Act. Previously, the Clean Air Act contained limited provision for permits, requiring only new or modified major stationary sources to obtain construction permits (Title I of the CAA).

Sources subject to the new permit requirements would generally include major sources that emit or have the potential to emit 100 tons per year of any regulated pollutant, plus stationary and area sources that emit or have potential to emit lesser specified amounts of hazardous air pollutants. However, in non-attainment areas, the permit requirements also include sources which emit as little as 10 tons per year of VOCs, depending on the severity of the region's non-attainment status (serious, severe, or extreme).

States were required to develop permit programs and to submit those programs for EPA approval by November 15, 1993. If a State does not have an approved plan within 5 years, EPA can impose and administer its own plan in the State. States are to collect annual fees form sources sufficient to cover the "reasonable costs" of administering the permit program, with revenues to be used to support the agency's air pollution control program. The fee must be at least $25 per ton of regulated pollutants (excluding carbon monoxide). Permitting authorities have discretion not to collect fees on emissions in an excess of 4,000 tons per year and may collect other fee amounts, if appropriate.

The permit states which air pollutants a source is allowed to emit. As a part of the permit process, a source must prepare a compliance plan and certify compliance. The term of permits is limited to no more than 5 years; sources are required to renew permits at that time. State permit authorities must notify contiguous States of permit applications that may affect them; the application and any comments of contiguous States must be forwarded to EPA for review. EPA can veto a permit; however, this authority is essentially limited to major permit changes. EPA review need not include permits which simply codify elements of a State's overall clean air plan, and EPA has discretion to not review permits for small sources. Holding a permit to some extent shields a source from enforcement actions: the Act provides that a source cannot be held in violation if it is complying with explicit requirements addressed in a permit, or if the State finds that certain provisions do not apply to that source.

Enforcement (Section 113)

In general, this section establishes Federal authority to impose penalties for violations of the requirements of the Act. The 1990 Amendments elevated penalties for some knowing violations from misdemeanors to felonies; removed the ability of a source to avoid an enforcement order by ceasing a violation within 30 days of notice; gave authority to EPA to assess administrative penalties; and authorized $10,000 awards to persons supplying information leading to convictions under the Act. The Act authorizes EPA to require sources to submit reports, to monitor emissions, and to certify compliance with the Act's requirements.

Stratospheric Ozone Protection (Title VI)

As amended in 1990, the Act establishes a national policy of phasing out production and use of "Class I" ozone-depleting substances (i.e., all fully halogenated chlorine or bromine containing compounds and carbon tetrachloride) by the year 2000, and methyl chloroform by 2002. "Class II" substances (i.e., other halogenated chlorine and bromine compounds, and others designated by EPA) will have their production frozen in 2015, and production ended by 2030. EPA already has accelerated the schedule to phase-out some ozone-depleting substances and may accelerate the schedule for others. Limited exemptions are allowed (e.g., for medical, aviation, and fire-suppression uses). EPA is to issue regulations on use and disposal of these chemicals that will minimize production and foster recycling and reuse. This title's authorities are expressly linked to the Montreal Protocol (an international accord phasing out chlorofluorocarbons), specifying that the more stringent requirement of either is effective.

(Source: CRS Report for Congress (Martin R. Lee, Coordinator). Summaries of Environmental Laws Administered by the Environmental Protection Agency . 95-59 ENR, January 3, 1995), p. 7-19)