We are approving a December 31, 1998, request from the Minnesota Pollution Control Agency (MPCA) for new air pollution control requirements for the Minnesota sulfur dioxide (SO<INF>2</INF>) State Implementation Plan (SIP) for Marathon Ashland Petroleum LLC (Marathon). These requirements were submitted in the form of an Administrative Order (Order) and include revisions associated with the addition of a new stack, revised emission limits for numerous sources, and other changes. The revisions result in an overall decrease in allowable SO<INF>2</INF> emissions from the facility. The new requirements have been evaluated through a computerized modeling analysis and have shown that they will attain and maintain the National Ambient Air Quality Standard (NAAQS) for SO<INF>2</INF>.