Approval and Promulgation of Implementation Plans Wisconsin

The Environmental Protection Agency is temporarily delaying the ozone attainment date for Manitowoc County from 1996 to 2007. This action suspends the automatic reclassification of Manitowoc County from moderate to serious nonattainment. Final approval of the new attainment date is dependent upon the results of an attainment demonstration for both upwind and downwind areas. Wisconsin is working toward completion of this attainment demonstration (which is due in mid-1997 for the Lake Michigan States) in conjunction with Illinois, Indiana, and Michigan, following the Phase I/Phase II Ozone Transport Assessment Group approach outlined in EPA's March 2, 1995 guidance memorandum from Mary Nichols entitled ``Ozone Attainment Demonstrations''. In this rulemaking, EPA is responding to Wisconsin's submittal of an overwhelming transport petition for Manitowoc County. Photochemical grid modeling was used to demonstrate that transport from upwind areas makes it ``practicably impossible'' for the county to attain the ozone National Ambient Air Quality Standard (NAAQS) by its original attainment date. EPA's action does not preclude the State of Wisconsin from submitting a request for redesignation to attainment for the county, based on three current years of clean air quality monitoring data.