The fire, named the Mind Fire, was first reported at 2:18 pm on Mines Road in Livermore.
At first fire officials said it was moving uphill, at a moderate to dangerous rate of speed.
An aircraft has since "made good progress slowing down the fire," and "retardant has been applied around the perimeter, according to Cal Fire.
Ground resources are now on the scene.
Firefighters at scene of a vegetation fire on Mines Rd, Livermore (Alameda County). AirTac 460 reporting 5 to 10 acres, moderate rate to dangerous of spread, moving uphill. #Minesfire
— CAL FIRE SCU (@calfireSCU) September 2, 2019
#Minesfire [update] Mines Rd, Livermore (Alameda County). Aircraft has made good progress slowing down the fire, retardant has been applied around the perimeter. Ground resources are beginning to arrive at scene. AA460 estimating 20-25 acres pic.twitter.com/Uf9NACxWfL
— CAL FIRE SCU (@calfireSCU) September 2, 2019
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