The crash was first reported shortly after 10 a.m.
The collision occurred when a tow truck going north on Highway 20 veered into the southbound lane, crashing into the tanker truck.
It is not known at this time what caused the the tow truck driver swerve.
Both drivers have been confirmed dead.
The tow truck belongs to Kilroy Towing out of Grass Valley and the tanker belongs to Williams Tank Lines in Stockton.
Authorities say 12,000-15,000 gallons of fuel has leaked.
Crews were on the scene attempting to gain control of the flames with foam.
Tankers can carry more than one type of cargo in separate compartments. When firefighters determined that it was gasoline they decided to let it burn off rather than spread it on the ground with toxic firefighting chemicals.
“Burning up the product just like it would in a wood fireplace, anything else. The more product that burns it allows all that contaminate to be disseminated into the air instead of in the ground," said CalFire Battalion Chief Bryan Ferrell.
Placer County environmental health specialists are on site working to determine any potential environmental impacts. Some of the gasoline escaped and hazmat crews were on hand to dam up as much gasoline as they could to keep it away from a drainage ditch and nearby Bear Creek.
Now that the fire has burned out, Caltrans will need to determine what damage there was to the roadway. Fish and Wildlife will also need to see what environmental actions need to be taken. The investigation into the crash has to take place by the CHP.
Highway 20 west of Interstate 80 reopened Thursday night, according to Caltrans.