The NRDC challenged EPA's residual-risk rulemaking and their periodic review of emission control technologies for the hazardous organic NESHAP (HON rule). NRDC v. EPA, No. 07-1053.
On Dec. 21, 2006, EPA issued a final rule affirming the existing NESHAP for the SOCMI. The HON rule was issued in 1994 and established maximum achievable control technology (MACT) standards to regulate emissions of hazardous air pollutants (HAPs) for production processes at major sources. The Clean Air Act (CAA) directs EPA to assess residual risks after the application of the MACT standards and to promulgate new standards when the maximum individual lifetime risk after implementation of the technology exceeds one in a million. The law also requires the agency to review and revise MACT technology standards, 'as necessary,' every eight years, considering developments in practices, processes and
In mid-2006, EPA proposed several options to amend the current emission standards for SOCMI units. The final rule reflected the agency's decision not to impose further controls and not to revise the existing standards based on its review of residual risk and technology.