US EPA is proposing to approve a state implementation plan (SIP) revision submitted by the Wisconsin Department of Natural Resources (WDNR) on June 7, 2012, concerning the State’s vehicle inspection and maintenance (I/M) program in southeast Wisconsin. The revision amends I/M program requirements in the active control measures portion of the ozone SIP to reflect changes that have been implemented at the state level since EPA fully approved the I/M program in 2001. Comments on the proposed approval must be received on or before May 28, 2013.
As background, Wisconsin has operated an I/M program in southeastern Wisconsin since 1984. The program is presently operating in Kenosha, Milwaukee, Ozaukee, Racine, Sheboygan, Washington and Waukesha Counties. Initially, all vehicles were inspected by measuring tailpipe emission levels. Since 2001, all model year (MY) 1996 and later cars and light trucks have been inspected by scanning the vehicle’s computerized second generation on-board diagnostic (OBDII) systems. EPA fully approved Wisconsin’s I/M program in 2001, As of July 2008, the program dropped tailpipe testing entirely and inspected all vehicles by scanning the OBDII systems.
The Wisconsin I/M SIP revision submitted on June 7, 2012 reflected several changes to the approved program. The most significant changes to the Wisconsin I/M program took effect beginning on July 2008 EPA is proposing to approve the revisions to the Wisconsin ozone SIP submitted on June 7, 2012, concerning the I/M program in southeast Wisconsin. EPA finds that the revisions meet all applicable requirements and will not interfere with reasonable further progress or attainment of any of the NAAQS.