Electricity regulators from across the US insisted this week that the Environmental Protection Agency is underestimating the time they'll need to meet EPA's newest air rules, and they want EPA to lay out standards now that will guarantee five years' compliance time and insulate them from civil liability.

EPA's Mercury and Air Toxics Standard gives generators three years from its publication date to comply, but allows state regulators to grant a fourth year and EPA to issue an administrative order allowing a fifth year in limited circumstances.

The agency has not legally published the rule yet, however, engendering confusion.

Gina McCarthy, one of EPA's assistant administrators, talked to the National Association of Regulatory Utility Commissioners about the issue and assertions that enforcement could cause blackouts.