CHAPTER 10 HAZARDOUS AIR POLLUTANTS: AN UPDATE OF ACTIVITIES UNDER SECTION 112 OF THE CLEAN AIR ACT
| Jurisdiction | United States |
(2000)
HAZARDOUS AIR POLLUTANTS: AN UPDATE OF ACTIVITIES UNDER SECTION 112 OF THE CLEAN AIR ACT
Parr Waddoups Brown Gee & Loveless
Salt Lake City, Utah
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185 So. State St., Ste. 1300
I. Introduction
One of the stated purposes of the federal Clean Air Act1 is to "protect and enhance the quality of the Nation's air resources so as to promote the public health and welfare and the productive capacity of its population."2 One of the primary ways that the Act achieves this purpose is to develop standards for both "criteria" air pollutants and "hazardous" air pollutants.
Criteria air pollutants are those pollutants "the presence of which in the ambient air results from numerous or diverse mobile or stationary sources."3 Since enactment of the Act in 1970 the U.S. Environmental Protection Agency4 has promulgated primary and secondary National Ambient Air Quality Standards5 for six (6) criteria pollutants.6
Hazardous air pollutants are those pollutants which are "known to be, or may reasonably be anticipated to be, carcinogenic, mutagenic, teratogenic, neurotoxic, which cause reproductive dysfunction, or which are acutely or chronically toxic."7
Section 112 of the Act, entitled "Hazardous Air Pollutants," deals with the issue of HAPs. This article discusses the history and current status of legal and regulatory developments under § 112 with special emphasis on developments of interest to the natural resources industry. The specific topics which are emphasized in this article include: regulation of the "residual risk" caused by HAPs after control of HAPs sources with the Maximum Achievable Control
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Technology,8 EPA's Urban Air Toxics Initiative,9 the National Emissions Standards for Hazardous Air Pollutants10 rule for primary copper smelters,11 and mercury emissions from coal-fired power plants.12
II. History of § 112, Pre-1990 Version
Section 112 was enacted as part of the 1970 amendments to the Act.13 At that time, § 112 simply defined HAPs as "air pollution which may reasonably be anticipated to result in an increase in mortality or an increase in serious irreversible, or incapacitating reversible, illness."14
EPA attempted to implement this early version of § 112 by use of an involved risk-analysis approach which proved to be slow and expensive. As a result, between 1970 and 1990, EPA officially designated only eight substances as HAPS.15 From these eight substances EPA did, however, promulgate twenty-two (22) NESHAPS for various categories of sources which emitted some of the eight designated HAPs.16
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The implementation of the 1970 version of § 112 was slow and controversial, in part, because of endless debate about the following language: "The Administrator shall establish any such [NESHAP] standard at the level which in his judgment provides an ample margin of safety to protect the public health from such hazardous air pollutants."17
This debate culminated with the decision by the United States Court of Appeals for the District of Columbia Circuit in Natural Resources Defense Council v. EPA.18 The primary issue in the case was the extent to which § 112 authorized EPA to consider economic and technological feasibility in establishing NESHAPS. NRDC argued (as the environmental groups had for years previous) that hazardous air pollutants are not safe at any level, that § 112 did not authorize any consideration other than public health, and that the emission standard for such pollutants must be set at zero. EPA, by contrast, argued that the health risks were not certain, there may be thresholds of safe exposure, and that § 112 authorized it to exercise its discretion in this situation to establish an emission standard based on "best available technology."19
The court's decision introduced an interpretation of § 112 that established a two-part process for EPA in establishing NESHAPS. In the first step, the court interpreted § 112 to require EPA to make, "an initial determination of what is `safe.' This determination must be based exclusively upon the Administrator's determination of the risk to health at a particular emission level."20 In the second step, the court stated that § 112 "permits the Administrator to take into account scientific uncertainty to determine what action should be taken .... *** It is ... at this point of the regulatory process that the Administrator may set the emission standard at the lowest level that is technologically feasible."21
Curiously, while apparently resolving the debate about the procedure to be employed by EPA for establishing NESHAPS under § 112, it actually set the stage politically for a fundamental overhaul of § 112 by Congress.
III. 1990 Amendments to § 112
During the late 1980's Congress began expressing dissatisfaction with what it viewed as the slow pace of EPA in both listing of HAPs and promulgating NESHAPS under the 1970 version of § 112.22 At the same time a political consensus emerged for a major amendment and reauthorization of the Act.
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A. Initial List of HAPs (§ 112(b))
In amending § 112, Congress replaced the basic provisions of § 112 with a detailed, technology-based regulatory scheme. The 1990 amendments to § 112 established an initial list of 189 HAPs.23 In establishing a HAPs list Congress utilized lists of hazardous chemicals and compounds previously established by federal and state regulators.24 Congress authorized EPA to periodically revise this initial list of 189 HAPs.25
B. Categories and Subcategories of HAPs Sources (§ 112(c))
In addition, Congress required EPA to publish a list of categories and subcategories of major sources and area sources of HAPs.26 Congress then established a schedule for promulgating emission standards for the listed categories and subcategories of HAPs sources.27 Within 2 years of enactment EPA was required to promulgate NESHAPS for 40 categories. By December 31, 1992, EPA was required to establish emission standards for coke ovens. By 4 years after enactment of the 1990 CAAA, EPA was required to promulgate emission standards for 25% of the listed categories and subcategories. An additional 25% of emission standards were required to be finalized by 7 years after enactment and within 10 years NESHAPS for all categories was required.28
EPA published the initial list of HAPs source categories and subcategories on July 16, 1992.29 The initial list contained 174 categories, of which 166 were major sources and 8 were area sources.30 Several changes have been made to the list of categories since the July 1992 publication. A revised list of categories was published on June 4, 1996.31 This revised list contained 175 source categories. A subsequent revision was published on February 12, 1998.32
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C. MACT and GACT Standards (§ 112(d) & (e))
The most significant change ushered in by the 1990 amendments was the introduction of technology-based standards for HAPs sources. This approach to HAPs regulation was undoubtedly inspired by the New Source Performance Standards ("NSPS") provisions of § 111 of the Act.
Both new and existing HAPs sources are required to comply with emissions standards which are equivalent to the "maximum degree of reduction in emissions of the [HAPs]", also known as the "Maximum Achievable Control Technology" or "MACT."33 By contrast, EPA may adopt less stringent emission standards for area sources which are equivalent to "Generally Available Control Technology" or "GACT."34 The default standard for all HAPs sources is MACT, but EPA retains the discretion to impose only GACT on area sources where appropriate.35
Congress adopted two definitions of MACT depending on whether the HAPs source is an existing source or new source. For existing sources this "MACT floor" is defined as, "the average emission limitation achieved by the best performing 12 percent" of sources in that category.36 If the source category contains fewer than 30 sources, MACT is "the average emission limitation achieved by the best performing 5 sources."37 For new sources, MACT is "the emission control that is achieved in practice by the best controlled similar source."38
In 1993 and 1994, there was a debate over the proper meaning and interpretation of the "12 percent" MACT floor statutory language for existing sources. This debate ensued in connection with EPA's promulgation of the MACT for the synthetic organic chemical manufacturing industry ("SOCMI") and other chemical processing facilities in the Hazardous Organic NESHAPS ("HON") rule. On March 9, 1994, EPA solicited public comments on the proper interpretation of this provision. Industry argued for the so-called "Lower Floor Interpretation" (88th percentile) while EPA suggested the "Higher Floor Interpretation" (94th percentile) was more "natural."39
On June 6, 1994, just 90 days after publication of the proposal, EPA published its final interpretation which was the Higher Floor. Under this interpretation the MACT standard is set at
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the average level of the top 12 percent of existing sources in the category considering such 12 percent as a group. EPA explained the concept as follows: "The EPA believes that the most natural and straightforward reading of this language would have EPA first determine the emission limitations achieved by the sources within the best performing 12 percent, and then average those limitations."40 EPA further stated that this interpretation, "will be presumptively followed in subsequent MACT rulemakings, but will not be binding."41
D. Case-By-Case MACT (§ 112(j))
The failure of EPA to meet its MACT promulgation deadlines in § 112(e) has real consequences for EPA, implementing states and source owners. If by 18 months after the expiration of a MACT deadline EPA has failed to promulgate a particular MACT, owners of sources in that category must...
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