U.S. lawmakers introduced at least four bills to slow or altogether block the Environmental Protection Agency from working on greenhouse gas standards.

Sen. Jay Rockefeller (D., W.Va.) introduced a bill Jan. 5 that would prevent the Environmental Protection Agency from enforcing its greenhouse gas requirements for two years. Rockefeller introduced a similar piece of legislation last year. He gathered dozens of supporters but his bill was never brought to the floor for a vote.

Marsha Blackburn (R., Tenn.) proposed a bill in the House on Jan. 5 that would blocks the EPA from regulating carbon dioxide and other greenhouse gas emissions under the Clean Air Act.

Rep. Ted Poe (R., Texas) introduced legislation that same day that would prevent the EPA from receiving funding for any type of cap-and-trade program for greenhouse gases.

On Jan. 6, Rep. Shelley Moore Capito (R., W.Va.) introduced a bill to suspend EPA’s work on greenhouse gases for two years.

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