On Tuesday, December 13th, the Environmental Protection Agency (“EPA”) released its final Federal Implementation Plan (“FIP”) to impose new sulfur dioxide (SO2) emission limits on six coal-fired electric generating units in Oklahoma.  In the preamble to its final rule, EPA justified its decision to issue the FIP by stating that Oklahoma’s regional haze State Implementation Plan (“SIP”) did not properly determine “best available retrofit technology” (“BART”) requirements for the units, thus leaving a gap that EPA was obligated to fill.  The final FIP differs very little from the proposed FIP, issued in March, over which the Oklahoma Attorney General has already filed a federal lawsuit. 

In responding to comments, EPA rejected claims by the utilities and the state of Oklahoma that the FIP represents an unauthorized federal takeover of Oklahoma’s regional haze program, arguing that such action was necessary in light of Oklahoma’s BART analysis, which EPA characterized as “unreasoned and unjustified.”  At the heart of the dispute between Oklahoma and EPA Region 6 over the implementation of the regional haze program is whether pollution controls known as dry scrubbers are cost-effective at the six plants.  In a regional haze SIP revision submitted to EPA on February 19, 2010, Oklahoma determined that dry scrubbers were unnecessarily expensive, particularly since the scrubbers would only result in a maximum visibility improvement of between 0.30 and 1.19 deciviews per plant at any Class I area, a level of improvement that even EPA admits is at or below the limit of what humans can perceive. 

The preamble to EPA’s final FIP recognizes but mostly rejects a variety of legal and technical arguments raised by commenters.  Although EPA revised its cost estimates upward somewhat in light of comments and also agreed to allow five years for compliance instead of three, the ultimate conclusion of EPA’s BART analysis remains that the six Oklahoma units should be required to achieve 0.06 lb/mmBtu, the level of emissions reduction assumed to be achievable with dry scrubbers.  EPA’s FIP does not actually require the Oklahoma utilities to install dry scrubbers, but instead repeatedly notes that the required emission reductions could also be achieved through the use of wet scrubbers or by switching the units to natural gas. 

The final FIP will become effective 30 days after publication in the Federal Register, expected within a month.  Oklahoma has promised to file suit on the final FIP, claiming that EPA’s actions fail to follow the proper procedures for adopting a FIP and unnecessarily usurp the authority granted to the state of Oklahoma by the Clean Air Act regional haze provisions.