Jennifer Straumins, vice president of investor relations for Calumet Specialty Products Partners, said neither incident affected base oil production at the plant. She said the explosion and fire on Monday involved one of the plants platformers used in gasoline production. That unit was actually down for maintenance, she said.

Calumet employs about two hundred contractors at the plant, she said, primarily to work on the expansion construction there.

Investigators believe a spark from an employee keying his radio or an ignition source in the form of a flame from a nearby heater may have caused Mondays explosion about 5:10 p.m., Shreveport Fire Department spokesman Brian Crawford told Lube Report yesterday.

Crawford explained that a worker was checking on a heated tank. When he went to check on the heating element underneath the tank, he noticed it was not lit, and that the gas being used to provide the energy source for it was still flowing, he said. According to Crawford, one worker went to shut the fuel valve off to the heater, and then another worker said he keyed his microphone. At that time, there was an explosion, he added.

The explosion injured two Calumet employees. Both were treated and released.

Crawford said the fire department assisted Calumets fire service crews, and the fire was quickly brought under control. When the explosion happened, it set the naphtha product, which is actually in the tank, on fire, he said. They shut down the product line supplying that fuel source. They just allowed it to burn itself out. There was minimal exposure to other areas of the plant. He said the fire was out by about 6 p.m.

The March 21 fire occurred in the late morning when asphalt leaked out of a storage tank, and seeped down into insulation outside the tank. The insulation caught on fire, and the fire began burning some of the asphalt, creating a lot of black smoke, Crawford said. No injuries were reported. Theres some new construction going on at the plant, and that was the area around where the fire occurred, he said.

Posted paraffinic base oil prices are unchanged in the United States this week. Crude closed at $62.93 per barrel yesterday on the New York Mercantile Exchange, according to Bloomberg. That was $3.68 above the price a week ago.