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Control of Emissions From New and In-use Highway Vehicles and Engines

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Environmental Protection Agency (EPA).


Notice; request for comment.


EPA requests public comment on a petition submitted by the International Center for Technology Assessment (CTA)and a number of other groups. The petition requests that EPA regulate emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N20), and hydrofluorocarbons (HFCs) from new motor vehicles and engines under section 202(a)(1) of the Clean Air Act (CAA or Act). The petitioners assert that emissions of these greenhouse gases contribute to global warming which may reasonably be anticipated to endanger public health and welfare. EPA has already received requests from a variety of stakeholders asking that we provide an opportunity to comment on this petition. To ensure wide exposure of the issues presented in the petition, EPA today requests comment on the issues raised by the petition and how EPA should respond to the petition. EPA has already established a public docket, and a number of comments on the petition have already been submitted and are available for inspection and public comment. The documents include several comments in opposition to the petition, including comments submitted by the Center for Regulatory Effectiveness, the American Petroleum Institute on behalf of 26 associations, and other commenters.


Comments must be received on or before May 23, 2001.


Interested parties may submit written comments (in triplicate if possible) to: EPA Air and Radiation Docket, Attention Docket No. A-2000-04, Room M-1500 (Mail Code-6102), 401 M St., SW, Washington, DC 20460.

Comments may also be submitted by electronic mail to: The docket may be inspected at this location from 8:30 a.m. until 5:30 p.m. weekdays. Docket information may also be obtained by calling (202) 260-7548. As provided in 40 CFR part 2, EPA may charge a reasonable fee for photocopying.

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Debbie Wood, Office of Transportation and Air Quality, Transportation and Regional Programs Division, (202) 564-8991.

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I. Summary of the Petition

On October 20, 1999, CTA, heading a coalition of 19 groups,[1] petitioned EPA to regulate certain greenhouse gas emissions from new motor vehicles and engines under section 202(a)(1) of the Clean Air Act. The petition, submitted pursuant to the First Amendment, the Administrative Procedure Act, and the Clean Air Act, requests that EPA regulate CO2, CH4, N2O, and HFC emissions from new motor vehicles and engines. Petitioners state that U.S. mobile sources are responsible for a significant amount of greenhouse gas emissions. Petitioners urge EPA to reduce adverse human health and environmental effects from global warming by regulating these emissions.

Petitioners argue that EPA must regulate greenhouse gas emissions from new motor vehicles and engines under CAA section 202(a)(1). First, they assert that the four greenhouse gases listed above constitute “air pollutants” as defined by the Act in section 302(g). Second, they argue that the emission of greenhouse gases contributes to pollution that is reasonably anticipated to endanger public health and welfare, the criteria for regulation under section 202(a)(1). Start Printed Page 7487

Section 202(a)(1) directs the Administrator to:

* * * by regulation prescribe (and from time to time revise) in accordance with the provisions of this section, standards applicable to the emission of any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines, which in his judgment cause, or contribute to, air pollution which may be reasonably anticipated to endanger public health or welfare.

Section 302(g) of the Act defines “air pollutant” as “any air pollution agent or combination of such agents, including any physical, chemical, biological, radioactive * * * substance or matter which is emitted into or otherwise enters the ambient air.”

Petitioners state that the four greenhouse gases identified in their petition have been determined to accelerate global warming. In addition, they argue that CO2 has already been determined by EPA to be an air pollutant.[2] Thus, they conclude that all four greenhouse gases meet the definition of “air pollutant” under section 302(g).

Further, petitioners assert that EPA must regulate these greenhouse gas emissions from new motor vehicles and engines because they endanger public health or welfare. Petitioners state that when determining what constitutes an endangerment to public health or welfare, the CAA allows the Administrator to make a precautionary decision to regulate a pollutant that “may reasonably be anticipated” to endanger public health or welfare. The petitioners point to statements by EPA and other Federal agencies as a basis for findings that global warming caused by these emissions may reasonably be anticipated to endanger public health and welfare. The threats to public health listed by the petitioners include increased occurrence of infectious, vector-borne and water-borne diseases, as well as direct effects on human health from heat stress, increased skin cancer, cataracts and immune system suppression.

The petitioners also seek EPA regulation of these greenhouse gases on the basis that they may reasonably be anticipated to endanger public welfare, as defined in the Clean Air Act. Section 302(h) provides:

All language referring to effects on welfare includes, but is not limited to, effects on soils, water, crops, vegetation, man-made materials, animals, wildlife, weather, visibility, and climate, damage to and deterioration of property, and hazards to transportation, as well as effects on economic values and on personal comfort and well-being, whether caused by transformation, conversion, or combination with other air pollutants.

Petitioners anticipate environmental harm from global warming to water resources, rangelands, forests, wetlands, fisheries, and bird populations. Petitioners also anticipate harm to human welfare in the form of reduced food production, in part due to increased pest populations, extreme weather, rising sea levels, reduced fresh water quality and quantity, and increased air pollution and allergens.

Petitioners next argue that it is technically feasible to reduce greenhouse gas emissions from new motor vehicles and engines. They conclude that technology exists to reduce CO2 through increasing the fuel efficiency of new vehicles. They also maintain that setting standards would lead to rapid market introduction of hybrid-electric and zero-emission vehicles.

Finally, petitioners maintain that the Administrator has a mandatory duty to regulate greenhouse gas emissions, given EPA findings to date. They further argue that “the precautionary purpose of the CAA supports” regulating these gases even if the Agency believes there is some scientific uncertainty regarding these issues. Petitioners cite Lead Industries Assoc. Inc. v. EPA and Ethyl Corp v. EPA in support of this principle (647 F.2d 1130 (DC Cir. 1980); 541 F.2d 1 (DC Cir.) (en banc) cert. denied 426 U.S. 941 (1976).

II. Request for Comment

EPA requests comment on all the issues raised in CTA's petition for regulation of emissions of greenhouse gases from new motor vehicles and engines under CAA section 202(a)(1). In particular, EPA requests comment on any scientific, technical, legal, economic or other aspect of these issues that may be relevant to EPA's consideration of this petition. EPA has not yet made any decisions on how to respond to this petition, apart from the decision to request public comment. A full copy of the CTA Petition and all supporting materials can be found in the docket for this action.

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Dated: January 12, 2001.

Robert Perciasepe,

Assistant Administrator, Office of Air and Radiation.

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1.  Alliance for Sustainable Communities, Applied Power Technologies, Bio Fuels America, California Solar Energy Industries, Clements Environmental Corporation, Environmental Advocates, Environmental and Energy Study Institutes, Friends of the Earth, Full Circle Energy Project, Inc., Green Party of Rhode Island, Greenpeace U.S.A., Network for Environmental and Economic Responsibility of the United Church of Christ, New Jersey Environmental Watch, New Mexico Solar Energy Association, Oregon Environmental Council, Public Citizen, Solar Energy Industries Association, the SUN DAY Campaign.

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2.  Petitioners cite the memorandum from Jonathan Z. Cannon, General Counsel to Carol Browner, Administrator, entitle “EPA's Authority to Regulate Pollutants Emitted by Electric Power gneraltion Sources,” April 10, 1998. EPA prepared this opinion in response to a Congressional request. The opinion states that each of four substances emitted from electric power generating units, sulfur dioxide, nitrogen oxides, mercury, and carbon dioxide, falls within the definition of “air pollutant” under section 302(g) of the CAA.

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[FR Doc. 01-1979 Filed 1-22-01; 8:45 am]