A refinery unit malfunctioned on Saturday at Tesoro Corp's 97,000 barrel per day (bpd) Los Angeles refinery in Wilmington, California, according to a notice the refinery filed with state pollution regulators.

The notice filed with the California Emergency Management Agency did not identify the unit involved, but Tesoro has been performing planned overhauls of production units at the refinery since Oct. 21.

California Los Angeles California Management