CROCKETT (CBS SF) — An explosion and fire ripped through two fuel storage tanks at a facility in Crockett Tuesday, prompting shelter in place orders and a creating a traffic nightmare after a stretch of a major freeway was closed.

The incident began at around 1:50 p.m. with an explosion at a storage tank farm at the NuStar Energy facility, which is nestled in the hills above the 90 block of San Pablo Ave. The fire ignited the vegetation on a hillside bordering the storage tanks. At least one of the tanks at the facility was filled with jet fuel.

#BREAKING: Watch as the fire at the #NuStar facility flares up again. Firefighters working to contain it https://t.co/DMaNMgCi2q pic.twitter.com/ejedhUGCdf — KPIX 5 (@KPIXtv) October 16, 2019

After burning for nearly eight hours, the blaze was fully contained around 9 p.m., Contra Costa Fire said.

NuStar Fire is now contained. County Environmental Health HazMat teams are working to assess the current health threat in Crockett, Rodeo, and Hercules. — Con Fire PIO (@ContraCostaFire) October 16, 2019

The shelter-in-place orders for Crockett, Rodeo and parts of Hercules were lifted at 9:45 p.m., the county Department of Public Health announced.

The fire created a billowing black plume of smoke that filled the skies for hours in addition to forcing the extended closure of a stretch of Interstate 80 in both directions for much of the day. The busy roadway was reopened around 9:20 p.m., but commuters faced gridlock for hours, especially near Pinole.

UPDATE: I-80 is OPEN in both directions. There is no longer eminent danger to the motoring public and the freeway is now open. Thank you to all our allied agencies for their combined effort in dealing with this incident. We are thankful for everyone’s safety. pic.twitter.com/EnLKi2QAaP — CHP – Contra Costa (@320PIO) October 16, 2019

Cummings Skyway between I-80 and San Pablo Ave will remain closed for the NuStar incident command post throughout the night, Con Fire said.

NuStar said in a preliminary statement that all personnel were safe and accounted for, and that the two tanks were holding low volumes of ethanol, less than 1% of tank capacity. Adjacent tanks were being cooled to minimize the risk of the fire spreading, the company said.

NuStar also said around 8 p.m. that they are investigating whether Monday night’s 4.5 magnitude earthquake in Pleasant Hill could have contributed to the fire and explosion at the facility.

The incident prompted officials from the John Swett Unified School District to cancel Wednesday classes, but the early containment of the fire allowed them to resume classes as regularly scheduled.

One contractor told KPIX 5 he had to hide in a drainage ditch when the explosion occurred in order to avoid burning to death. He was unable to evacuate on his own, but was not injured.

Crocket Fire Chief Dean Colombo said the NuStar facility had been inspected a few months prior to Tuesday’s fire. But the facility does not have its own fire brigade or fire equipment, Colombo said. It does have fixed equipment to cool down tanks on the exterior in the event of a fire.

The fire was burning just a few hundred feet from Interstate 80 just south of the Cummings Skyway in Crockett. Aside from I-80, authorities closed a number of roads in the area because of the fire.

I-80

We will have shutdowns on I-80 from Hwy-4 to the Carquinez Bridge due to the Refinery in Rodeo. Seek alternate routes if I-80 is your normal travel route. More info when we have it. pic.twitter.com/3LhpFK5mqm — CHP – Contra Costa (@320PIO) October 15, 2019

Eastbound I-80 traffic was being diverted off to SR-4. In Solano County, westbound I-80 traffic is being diverted off at Maritime. The closure snarled traffic on both sides of the closure, with eastbound traffic backed up past San Pablo.

Approximately 200 firefighters and support personnel were on scene battling the fire. While there were still flames and smoke coming from the area of the melted tanks, fire crews seemed to be making progress as they poured water and foam onto the fire.

Firefighters were battling the vegetation flames but appeared to be letting the fuel burn itself out. Firefighting aircraft dropped water and retardant on the hillside surrounding the storage tanks.

Hand crew coming out of valley near #NuStar pic.twitter.com/fbNfq6X7mj — Andria Borba (@AndriaKPIX) October 16, 2019

Cal Fire reported shortly before 7 p.m. that the vegetation fire remained at about 15 acres and 75 percent containment.

The shelter in place orders were issued for residents in the area warning of hazardous materials being released. The smoke plume could be seen for miles including from San Francisco.

Major refinery fire in Rodeo, please shelter in place. Literally blew the top off of the facility. pic.twitter.com/UvOw3AEKIY — F-WAYNE (@5whiteboy10) October 15, 2019

The shelter in place order urged people in the area to go inside, close all windows and doors, and turn off all heaters, air conditioners, and fans. In addition, people were urged to cover any cracks around doors or windows with tape or damp towels and remain indoors until further instruction.

Children, the elderly, and individuals with pre-existing respiratory conditions would be the people most affected. Once the shelter in place orders were lifted, county health officials advised people in the affected areas to “air out” their homes by opening windows.

Earlier, witnesses reported explosions shaking the area. Video showed large flames and black smoke coming from the location where two of the storage tanks collapsed.

A woman was loading her tanker truck at the refinery, when the explosion rocked the facility.

“I was loading my truck at that facility when it exploded,” said the woman, identified as Michelle. “I had just pulled off the rack and gotten my paperwork. I had my head down doing paperwork and I felt the ground rumble. I knew there was an earthquake yesterday. So I didn’t panic.”

“But I looked up and saw a bunch of people running. I looked and I saw the fire and the smoke. I immediately started my truck and headed up the hill. I got to the top of the Cummings Skyway and I could see the tops of two tanks completely engulfed in flames.”

2 loud explosions shook my house in Hercules. Came outside to this! Rodeo refinery looks like it’s on fire #Hercules #Rodeo pic.twitter.com/FunsopwcCe — Raudel Wilson (@raudelwilson) October 15, 2019

@KPIXtv View of Rodeo fire from flight into San Francisco pic.twitter.com/4paQGhNmy4 — Rene Voss (@renepvoss) October 15, 2019

KPIX 5’s Andria Borba contributed to this report.