Environ. Sci. Technol. 2000, 34, 3857-3863
Clearing the Air: Using Scientific Information to Regulate Reformulated Fuels PAMELA M. FRANKLIN,* CATHERINE P. KOSHLAND, DONALD LUCAS, AND ROBERT F. SAWYER Energy and Resources Group, University of California, Berkeley, 310 Barrows Hall, Berkeley, California 94720
The gasoline oxygenate MTBE (methyl tert-butyl ether) was widely adopted across the United States in the 1990s as a key component of federally mandated oxygenated and reformulated fuels. The regulations implementing statutory mandates for oxygenated fuels were promulgated without a comprehensive evaluation of the environmental or health consequences of using MTBE or other oxygenates in such large quantities. Policymakers only belatedly realized the environmental ramifications of increased levels of MTBE in gasoline, especially groundwater contamination resulting from leaking fuel tanks. The policy process that led to MTBE’s predominance was flawed, since no systematic attempt was made a priori to evaluate multimedia implications of MTBE’s widespread use. The history of MTBE in the United States illustrates several typical, but problematic, features of environmental policymaking. It reveals how the scale of chemical usage directly impacts actual and perceived environmental effects. It highlights how institutional factors constrain policymakers through statutory mandates, regulatory agency organizational structures, and the strong influence exerted by political-economic actors even in supposedly “technical” debates. Finally, the MTBE case reveals barriers to effective scientific and technical communications among policymakers, regulated industries, special-interest groups, and the public.
Introduction Since it was first introduced on a large scale in wintertime oxygenated gasoline (“winter oxyfuel”) programs in cities such as Denver, Milwaukee, and Fairbanks in the late 1980s, the gasoline oxygenate MTBE (methyl tert-butyl ether) has generated national headlines. It was promoted by the oil industry and by state and Federal environmental agencies as a remarkable compound that boosted gasoline’s octane and burned “cleaner”. Provisions in the 1990 Clean Air Act Amendments mandated the use of oxygenated compounds in winter oxyfuels and in Federal reformulated gasoline (RFG). MTBE became the oil refiners’ “oxygenate of choice” to meet these requirements. Initially, MTBE received bad press due to its pungent odor, anecdotal claims about its acute health effects, and higher gasoline costs, which many consumers associated with MTBE. Later, MTBE groundwater contamination from leaking fuel storage tanks became the leading cause of MTBE’s notoriety, documented on the front pages * Corresponding author phone: (415)447-8683; fax: (510)642-1085; e-mail:
[email protected]. 10.1021/es0010103 CCC: $19.00 Published on Web 08/04/2000
2000 American Chemical Society
of national newspapers and on the television program 60 Minutes. Federal policymakers did not comprehensively evaluate MTBE’s potential adverse health and environmental effects or its full energy and economic impacts before they allowed widespread adoption of the compound. This paper explores the dynamics of the Federal-level science policy process behind MTBE’s rise and fall in the United States. We explore what regulatory institutional characteristics led to MTBE’s adoption with so little systematic consideration of its environmental consequences.
The MTBE History Legislative Background. MTBE was first approved for use in the United States in 1979 as an octane booster to replace tetra-ethyl lead, typically at 1-3 vol % (1). In 1987, the Environmental Protection Agency (EPA) approved gasoline blends containing up to 11 vol % MTBE (2, 3). MTBE was catapulted to prominence as a consequence of the 1990 Clean Air Act Amendments, in which Congress established unprecedented prescriptions for gasoline formulations to reduce automotive emissions. The Amendments mandated winter oxyfuel in 40 areas nationwide (primarily northern cities) to help reduce vehicle carbon monoxide (CO) emissions. Adding an oxygen-containing compound to gasoline promotes more complete burning of the fuel, reducing vehicle CO and hydrocarbon emissions. The Amendments also mandated reformulated gasoline (RFG) in 10 urban areas nationwide with the most severe ozone problems. RFG is intended primarily to reduce vehicle emissions of photochemical ozone precursors, especially volatile organic compounds (VOCs) and nitrogen oxides (NOx) as well as toxic compounds. Although photochemical ozone is a more severe problem in the summertime, RFG requirements are effective year-round. The statute contains both prescriptive and performance-based standards for RFG (Table 1). It requires reduced levels of sulfur, benzene, and aromatics in gasoline and limits fuel vapor pressure and distillation characteristics. The Amendments specify that RFG contain a minimum oxygen content of 2.0 wt %. Federal RFG and oxyfuel requirements are “fuel-neutral” and do not mandate any particular oxygenate. In theory, refiners have several viable oxygenate options, including ethers (such as MTBE; or ethyl tert-butyl ether or ETBE; or tert-amyl methyl ether or TAME) and alcohols (e.g., ethanol or tert-butyl alcohol). In practice, based on primarily on cost, the most realistic choices for gasoline refiners were, and continue to be, MTBE and ethanol (4). The statutory specifications for RFG’s composition left the EPA little flexibility in designing the RFG regulations. To implement the statute, the EPA conducted a regulatory negotiation (“reg-neg”) process that included parties from the auto and oil industries, environmental groups, state and Federal agencies, and ethanol and agricultural interests (2, 5, 6). An agreement was reached among the parties in August 1991; the final RFG rules were published in 1994, and Phase 1 requirements became effective in 1995 (5, 6). Although the Federal RFG program preempts state regulations, California has established its own reformulated gasoline program through a special waiver in the Clean Air Act (Section 211(c)(4)(B) of the 1990 Amendments). MTBE’s Emergence as the “Oxygenate of Choice”. While the 1990 Amendments fuel provisions were being developed, both industry and legislators understood that MTBE and ethanol would be the predominant oxygenates (5). ARCO, then the world’s largest MTBE manufacturer, was an avid VOL. 34, NO. 18, 2000 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
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TABLE 1. Reformulated Fuel Standards (9)a fuel parameter
conventional gasoline pre-RFG
Federal RFG phase 1 complex avg stdb
Federal RFG phase 2 avg stdc
California RFG phase 2 avg stdd
Reid vapor pressure (psi) sulfur (ppm) oxygen (wt %) aromatics (vol %) olefins (vol %) E200 (%)d E300 (%)e benzene (vol %)
8.7/7.8 339
