EPA Weighs Carbon Dioxide Limits

LAST WEEK, EPA began deliberations that could lead to production of cars and trucks that emit less greenhouse gases.

EPA is deciding whether to allow California to impose standards that would limit emissions of greenhouse gases from new cars. Under the Clean Air Act, EPA must give formal assent before a state can adopt vehicle emissions standards that are more stringent than federal ones.

Approval of California's request would pave the way for 11 other states that have similar vehicle emissions standards pending: Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington. These 11 states and California together account for about one-third of U.S. vehicle sales.

EPA is considering California's request in the wake of the April 2 Supreme Court ruling that CO₂ and other greenhouse gases are pollutants that can be regulated under the Clean Air Act. The high court rejected the Bush Administration's argument that EPA lacked authority to control greenhouse gases (C&EN, April 9, page 9).

At a hearing of the Senate Environment & Public Works Committee on April 24, EPA Administrator Stephen L. Johnson announced that the agency was starting a formal process to consider California's request. Although California submitted the request in December 2005, EPA waited for the Supreme Court to decide the greenhouse gas case before acting on it.

At the hearing, senators tried to pin down how long it will take EPA to finalize its decision on California's request. But Johnson refused to suggest a time frame, saying only that the agency will "move expeditiously but responsibly."

Sen. Barbara Boxer (D-Calif.), chair of the committee, told Johnson, "We expect action by the middle of this summer."

Meanwhile, California Gov. Arnold Schwarzenegger warned Johnson in an April 25 letter that his state will sue EPA if the agency doesn't decide by the end of October.