About 600 workers were evacuated Friday evening from the Holly Refinery in West Bountiful following a leak of hydrofluoric acid.
South Davis Metro Fire Chief Jim Rampton said fire and haz-mat crews responded to the call but refinery workers, who are trained for quick responses to hazardous incidents, had already contained the leak. Three people were evaluated on the scene and one man was transported to a Salt Lake hospital with minor acid burns.
Vapors from the leak did not pose a hazard.
Rampton said the refinery is in the midst of a "turnover" operation, a period when maintenance and upgrades occur, and is not currently in operation.