The brush fire was reported at 1:32 p.m. near Kirker Pass and Hess roads, near the former Concord Naval Weapons Station.
The fire was about 25 percent contained as of 5 p.m., Contra Costa County Fire Prevention District Fire spokesman Robert Marshall said. By about 6 p.m. it was 60 percent contained and about 45 minutes later, it was 100 percent contained.
A containment line has been set up around the fire, however the "wind is starting to pick up pretty good," he said around 5 p.m.
Two tool sheds and a barn have been destroyed in the blaze. Marshall said no animals were inside and no residents were living in the buildings.
Cal Fire aircraft have been called in to battle the flames from the air, Marshall said.
There are no known injuries, he said.
Kirker Pass Road remained closed as of 5 p.m., according to the California Highway Patrol.
Local fire departments including the East Contra Costa County Fire Protection District and the San Ramon Valley Fire Department are assisting.
The temperature was about 98 degrees Ferinheight. The cause of the fire is unknown.
ABC7 News contributed to this report.