FAIRBANKS—A fire destroyed a storage building and workshop at the HC Redi-Mix cement plant on the Old Richardson Highway near the north end of Badger Road late Monday morning.

Nobody was injured in the blaze, which may have been started by sparks from workers welding or grinding in the building, said Fire Chief Jeff Tucker of the North Star Volunteer Fire Department. The inside of the building was lined with foam polyurethane insulation, which is highly flammable, he said.

"It goes up in a heartbeat," Tucker said, adding that the cause is still under investigation. "It's just hard gasoline."

North Star received a report of the fire and some explosions at 10:57 a.m. and was on scene within 10 minutes. Black smoke and flames were pouring out the top of the large, metal building when firefighters arrived.

The building contained several pieces of heavy equipment and construction materials. More explosions could be heard as firefighters from five local fire departments battled the blaze. The explosions were likely the result of acetylene and propane tanks inside the building, Tucker said.

There were also two large fuel tanks on the outside of the building that did not explode. Plant workers were able to use a front end loader to skid one of the tanks away from the building, but the other was too large to move, Tucker said.

Firefighters kept the fire contained inside the building by spraying water on the flames from multiple tankers on scene. Fire departments from North Star, North Pole, Fairbanks, Fort Wainwright and Steese responded to the fire.

The fire put up a large plume of black smoke visible from Fairbanks and North Pole.

HC Redi-Mix owner Bill Hoople could not be reached for comment about the fire and what impact it would have on the plant.

Contact staff writer Tim Mowry at 459-7587. Follow him on Twitter: @FDNMoutdoors.