July 23, 1999

EPA's Tier 2 Standards for Vehicle Emissions and Gasoline Sulfur Content

  • Susan Dudley

    Director, George Washington University Regulatory Studies Center
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Control of Air Pollution from New Motor Vehicles: Proposed Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements

Stated Purpose:

Reductions in emissions from passenger cars and light trucks "would provide for cleaner air and greater public health protection, by reducing ozone and PM pollution."

Summary of RSP Comment:

EPA should not proceed with the proposed stringent vehicle and gasoline standards. It has not demonstrated that they are (1) necessary, (2) feasible, and (3) cost-effective, as required by the Clean Air Act. EPA's lack of support for the emission and sulfur levels it has proposed reflects the same flaws that led the District Court to rule on its 1997 ambient air quality standards, that EPA had interpreted sections of the CAAA "so loosely as to render them unconstitutional delegations of legislative power."

EPA has not demonstrated that its proposal is necessary to meet the current ozone air quality standard, since the vast majority of the nation will be in compliance with them by the time the effects of this proposal are seen. Furthermore, its evaluation of cost-effectiveness is based solely on estimates of average cost-per-ton of ozone precursor emissions removed, which does not capture the very large differences in costs and benefits across the nation. Our own analysis of EPA data reveals that consumers in some western states will pay ten times EPA's national average to reduce one ton of emissions. Furthermore, these consumers will derive no benefit, since they already enjoy air quality that meets the standards, and in some areas, they will actually see a decline in air quality. In addition, the cost-effectiveness of emission controls for different classes of vehicles varies significantly.

Given state and regional track records for instituting necessary controls (including reformulated gasoline and inspection and maintenance programs), EPA should leave decisions regarding the sulfur content of gasoline to individual states, perhaps with the cooperation of, or recommendations from, the Ozone Transport Assessment Group (OTAG). If EPA feels compelled to issue federal regulations governing gasoline sulfur content, it should seriously evaluate a petroleum industry proposal whereby low-sulfur gasoline would be provided only for the eastern half of the nation. Furthermore, California's low emission vehicle rules, and the OTAG-state-initiated NLEV program offer evidence that even vehicle standards do not need to be mandated at the federal level.