Docket No. EO-05-01. This report describes AERMOD modeling results performed for Unit 1 at Mirant's Potomac River Generating Station. The purpose of these runs was to demonstrate that operation of Unit 1 for 24 hours a day loads from 35MW to 88 MW with the use of trona to reduce SO2 emissions will not cause or contribute to modeled excceedences of the National Ambient Air Quality Standards (NAAQS). Mirant proposes to use trona on an as needed basis to limit SO2 emissions to less than 0.89lb/MMBtu and 14,800 lb/day, whichever is more stringent.