Area fire crews needed assistance from a state Department of Natural Resources helicopter to quell a weekend grass fire on 3M property in Cottage Grove.
Crews from 3M, Cottage Grove, Newport, St. Paul Park and DNR fire departments battled the flames on 3M-owned land in southern Cottage Grove for nearly five hours last Saturday afternoon before extinguishing the blaze that officials estimated torched roughly 500 acres of grass and woodland area near the Mississippi River.
Steep hills and heavy brush hindered firefighters' efforts, said Cottage Grove Fire Chief Bob Byerly. A DNR helicopter was called in to dump approximately 10,000 gallons of water on hard-to-access hot spots in an effort to douse the flames.
Byerly said officials suspect a spark from a passing train sparked the fire.