EPA isn’t talking either about how they came up with the regulations.
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House Republicans threatened to subpoena Environmental Protection Agency (EPA) Wednesday for various documents related to its rule unveiled last year to limit carbon emissions from new power plants.

The Energy and Commerce Committee has been communicating with EPA officials since March about the rules for new power plants, which were formally published in January. The rules set carbon pollution limits based on what is achievable under carbon capture technology.

But the Clean Air Act only allows the EPA to mandate standards based on technology that is “adequately demonstrated.” The EPA based its standards on three carbon capture projects that are funded by the Energy Department.