Salt Lake City-A March 31 grass fire southwest of Cheyenne, Wyo., at no time threatened the Dyno Nobel ammonium nitrate plant located outside the city, according to Dyno Nobel headquarters offices located here. Press reports called the grass fire, which was at first considered extinguished and then re-ignited, one of the largest in recent memory, and indicated it burned behind the Dyno Nobel plant. Approximately 700 acres were involved. “There must have been some cow patties or small areas around there with the low humidity during the day that picked up and reignited,” Laramie County Fire District 2 spokesman Lew Simpson was quoted as saying. A statement from Dyno Nobel said the grass fire was well managed and there were no injuries, and no structures were threatened. Personnel at the site were on alert and closely monitored firefighters as they fought the grass fire. The Dyno Nobel site has its own fire truck and has professionally trained personnel to handle emergency situations. Site drills are held regularly with various emergency responders in the area.