Train wheels reportedly sparked about 10 grass fires shortly after 1 p.m. in the area of Waterfront Road and Waterbird Way near Martinez, Contra Costa County Fire Protection District spokeswoman Emily Hopkins said.
As of 5:30 p.m., firefighters were still working to put out some hot spots in the area, but were making progress in extinguishing the flames, Hopkins said.
Hopkins said fire engines are being released from along Waterfront Road in Martinez and trains in the are running again after being stopped for several hours.
Firefighters from Tesoro's Golden Eagle Refinery and the Concord Naval Weapons Station assisted in the effort. A helicopter was also called to the area in case firefighters needed a water drop, Hopkins said.
The fires were burning about a quarter of a mile from the guard gate at the Tesoro Refinery, Hopkins said.