The smoke stacks at American Electric Power's (AEP) Mountaineer coal power plant in New Haven, West Virginia, October 30, 2009. In cooperation with AEP, the French company Alstom unveiled the world's largest carbon capture facility at a coal plant, so called 'clean coal,' which will store around 100,000 metric tonnes of carbon dioxide a year 2,1 kilometers (7,200 feet) underground.National Journal

House Republicans are getting more aggressive in their effort to transform obscure provisions of a 2005 energy law into the strands that unravel EPA's carbon-emissions rules for newly constructed power plants.

The Energy and Commerce Committee's GOP leaders, in a new letter to the Environmental Protection Agency, demand the names of people at EPA who determined that the proposed emissions rules don't run afoul of the Energy Policy Act of 2005.

The letter also seeks a slew of internal documents.

Here's what the fight is about: The 2005 law authorizes tax credits and Energy Department funding for projects using technology that traps carbon emissions from coal-based energy projects.

But provisions in the same law say a technology can't form the basis for future EPA regulations simply because it's deployed at these "clean-coal" projects.

EPA rules proposed in September would require future coal-fired power plants to trap and store a substantial amount of their carbon emissions.

The 2005 provisions suddenly matter because EPA has pointed to Energy Department-backed projects when making the case that carbon capture and storage is far enough along to form the basis for the rule.

But EPA says it's in the clear, because this handful of projects backed under the 2005 law are far from the sole basis for the agency's determination that CCS is ready for prime time.

The agency, in a detailed memo released several weeks ago, said it also reviewed projects that aren't funded under the 2005 law and other information.

But Republicans say they're not convinced. The letter seeks expansive documentation from EPA on the topic, such as internal emails and communications with other agencies.

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