Many of these new restrictions, they point out, were proposed in the budget debate earlier this year and failed. They are back, the Democrats say, because Republicans are doing the bidding of industry and oil companies.

“The new Republican majority seems intent on restoring the robber-baron era where there were no controls on pollution from power plants, oil refineries and factories,” said Representative Henry A. Waxman, a California Democrat, excoriating the proposal on the floor.

Environmental regulations and the E.P.A. have been the bane of Tea Party Republicans almost from the start. Although particularly outraged by efforts to monitor carbon dioxide, the primary greenhouse gas linked to the warming of the Earth’s atmosphere, freshmen Republicans have tried to rein in the E.P.A. across the board — including proposals to take away its ability to decide if coal ash can be designated as a toxic material and to prevent it from clarifying rules enforcing the Clean Water Act.

The appropriations bill in question covers the Department of Interior, the Forest Service and the E.P.A., and it was voted out of committee and onto the House floor strictly along party lines — with the Republicans prevailing 28 to 18. The bill cuts annual combined funding for agencies by 7 percent — and by nearly 18 percent for the E.P.A. alone — but it is controversial mostly because of the onslaught of policy changes.

Representative Norm Dicks, Democrat of Washington and ranking minority member on the appropriations committee, said Republicans were adding provisions unchecked to the law and getting away with very little scrutiny. He expected even more regulatory rollbacks to be added to the bill this week. The bill is under open debate on the House floor, and policy changes requested by members but not included by the appropriations committee can now be added one by one to the bill, in addition to the 39 riders that came out of the committee.

“It is already like a wish list for polluters,” Mr. Dicks said, “and it is going to get worse on the floor.”