The blaze is burning at the Ashland Chemical Company on Crocker Circle where a tanker containing ethyl acetate apparently caught fire. That's a toxic chemical that can cause severe respiratory problems.
Firefighters are keeping back because of the intensity of the heat and concerns about a larger explosion.
They're waiting on crews from Travis Air Force Base to arrive with a special foam that's used against chemical fires.
People who live near the facility are advised to keep their doors and windows shut and bring in pets if possible.
