Approval and Promulgation of Implementation Plan; Illinois

On May 5, 1995, and May 26, 1995, the State of Illinois submitted a State Implementation Plan (SIP) revision request to the United States Environmental Protection Agency (EPA) for reactor processes and distillation operation processes in the Synthetic Organic Chemical Manufacturing Industry (SOCMI) as part of the State's control measures for Volatile Organic Material (VOM) emissions for the Chicago and Metro-East (East St. Louis) areas. VOM, as defined by the State of Illinois, is identical to ``volatile organic compounds'' (VOC), as defined by EPA. VOC is one of the air pollutants which combine on hot summer days to form ground-level ozone, commonly known as smog. Ozone pollution is of particular concern because of its harmful effects upon lung tissue and breathing passages. This plan was submitted to meet the Clean Air Act (Act) requirement for States to adopt Reasonably Available Control Technology (RACT) rules for sources that are covered by Control Techniques Guideline (CTG) documents. The control measures specified in this SOCMI SIP revision are not expected by Illinois to further reduce VOC (VOM) emissions in the Chicago area, or in the Metro-East area, because Illinois has identified only two sources which meet the applicability criteria, and Illinois states that the sources are already in compliance with the State's SOCMI rules. This rulemaking action only addresses compliance with the RACT requirement for one source, Stepan Company's Millsdale facility. The EPA is approving the State Implementation Plan (SIP) revision request submitted by the State of Illinois as it applies to Stepan Company's Millsdale Facility. Action on the revision request as it applies to other subject facilities, and on the overall revision request, will be taken at a future time.