In an August 25 letter to Administrator Gina McCarthy, the AGs claimed supporting documents were inadequate as indicated by Sec. 307(b) of the Clean Air Act, which requires “all data, information and documents … on which the rule relies … .” The move is expected to support the basis for a formal legal challenge to the existing source rule under Sec. 111(d) of the law.

The letter, organized by West Virginia Attorney General Patrick Morrisey, said the existing source rule docket lacks both year-to-year data showing how facilities can comply with ambitious heat rate improvements, as well as modeling runs used by the EPA, “without which the states and the public cannot comment meaningfully on the proposal.” The AGs argue that finalizing a rule without this critical documentation would be “unlawful” and called for the rule to be withdrawn “immediately.” Almost all of the signatories signed onto an earlier legal challenge to EPA’s authority to regulate greenhouse gas emissions.

In related news, the National Lieutenant Governors Association recently approved a resolution calling on the EPA to delay its power plant rule and make adjustments needed to ensure grid reliability and state authority are not impaired. The resolution asserts the rule as proposed would “increase natural gas prices by 9% to 12%,” cause “the retirement of 46,000 to 49,000 megawatts of coal-fueled electricity,” and force energy price increases to be “borne disproportionately by low-income and middle-income” families.