Turning up the heat on Republicans in the final weeks before the U.S. elections, Democrats and environmentalists are requesting documents from the U.S. EPA detailing the Bush administration’s effort to roll back clean-air regulations on older coal-fired power plants and refineries. But EPA officials have refused to pony up the evidence, and Sen. James Jeffords (I-Vt.), chair of the Senate Environment and Public Works Committee, has threatened to subpoena the agency if it doesn’t comply with the request — his third such threat this year. Says the senator, “This action is another example in an unprecedented and disturbing pattern of keeping information from Congress and the public. The administration has misled this committee and the Congress.” The EPA contends that it needs more time before it can release the information, in order to craft confidentiality guidelines for the documents in light of pending clean-air enforcement cases.