An acid tank at The Mosaic Co.’s phosphate processing plant at Riverview, Fla., exploded Saturday, Nov. 23, while routine maintenance was being performed and two workers received minor injuries. Both were taken to local hospitals for treatment, according to local news reports. A spokesman for Mosaic was not immediately available for comment, but reports said the blast lifted the roof of the tank about 100 feet into the air and a plume of smoke rose about 100 feet above the top of the facility. The tank was empty at the time. Investigators had not determined the cause of the explosion as of early Monday morning, Nov. 25. It was not clear whether the injured workers were employees of the company or contract workers.