Well, under some administrations, EPA has a history of doing precisely that. Traditionally, state environmental law is open to citizen legal action or even Federal intervention if it does not mandate standards of equal or greater stringency than the mirroring Federal statute. The problem in the instant situation, the Marcellus Gas activity, is that most of the pertinent Federal standards are found in the Federal Clean Water Act, Safe Drinking Water Act and National Environmental Policy Act. With the passage by Congress of the Energy Policy Act of 2005, much of the prior oversight and regulation of oil and gas under the above named Federal laws was removed and the industries largely exempted from the Federal statutes.
So, there may not be a whole lot that EPA or the various environmental foundations that use the citizen's suit provision of CWA to break up enforcement (usually consent decree situations) logjams can do, even if they wanted to.
