Jan. 23 (Bloomberg) -- The U.S. Environmental Protection Agency ignored the advice of its own employees in rejecting California's request to set rules on automotive carbon dioxide emissions, the head of a Senate committee said.

``It's clear that EPA's own experts told Administrator Stephen Johnson that California's case for the waiver is solid,'' Barbara Boxer, a California Democrat who is chairman of the Senate Committee on Environment and Public Works, said at a news briefing today in Washington.

EPA officials showed members of her committee's staff documents including a 46-page presentation of recommendations from agency employees, Boxer said. Several portions of the documents were blocked out with duct tape, which the staff members removed to read and make handwritten notes, she said.

The U.S. agency on Dec. 19 denied the state's request to set emissions rules tougher than federal standards. Johnson said then that an energy bill signed by President George W. Bush already achieves greenhouse gas reductions through new fuel-efficiency standards.

``The documents show that Administrator Johnson was given a range of options, and he took the decision,'' Jonathan Shradar, an EPA spokesman, said in an interview. The agency didn't want the documents to be made public because they are ``part of ongoing litigation'' between the EPA and 16 states, Shradar said.

Boxer said that agency staff members told Johnson in a presentation that ``California continues to have compelling and extraordinary conditions in general as confirmed by several recent EPA decisions,'' for the state's request to be granted. The presentation noted that ``California exhibits the greatest climatic variation in the U.S.,'' the senator said.

Boxer's committee will hold a hearing tomorrow on the EPA's decision, and Johnson is expected to testify. The governors of Maryland, Michigan, Pennsylvania and Vermont also are scheduled to appear.

To contact the reporter on this story: Gopal Ratnam in Washington at gratnam1@bloomberg.net

Last Updated: January 23, 2008 14:16 EST