Cause of NuStar Explosion and Fire Under Investigation, 'No Concerns' About Integrity of Other Tanks

Updated Wednesday, 1 p.m.

Fire crews remain on the scene of Tuesday's explosion and hours-long fire at NuStar Energy's storage facility in Crockett, where two large storage tanks that held ethanol burned almost entirely.

The fire led to a nearly 7.5-hour shelter-in-place order for parts of Contra Costa County and the shutdown of Interstate 80 in both directions.

Contra Costa County Fire spokesman Steve Hill said all of the facility's tanks have now been inspected, and officials have no concerns about the integrity of nearby tanks.

Firefighters from Chevron, Shell and Marathon oil's nearby refineries are working with NuStar firefighters Wednesday to tour the site and make final determinations, Hill said.

"They're going to vent adjacent tanks ... to relieve pressure and prevent fire," Hill said at a news conference.

Secondary containment ponds around the two burned-out tanks are now filled with material.

"We believe that's mostly water now," Hill said, noting that a team is making a final determination of the makeup of that material. Crews are now working to pipe runoff composed of ethanol, water and foam into containers.

Officials believe there's no further risk of fire, but said they're keeping blankets of fire-suppression foam applied to the site out of an abundance of caution. Fire crews will remain on-scene in case another ignition is triggered.

"We’ve used about 15,000 gallons of firefighting foam in the course of yesterday afternoon and into last night," Hill said.

"When the fire began, [the two tanks that burned] were filled to 1% of their capacity," Hill said.

He noted crews dodged multiple bullets in the last 24 hours in regard to how much worse things could have been.

"Even at 1% capacity those tanks had a lot of ethanol in them. That's approximately 3,000 barrels, which comes to about 126,000 gallons of ethanol in each tank."

Of the nearby tanks that were threatened, most of them contained ethanol — but one of them contained jet fuel.

Regarding health concerns for nearby residents, Contra Costa County's chief environmental health and hazardous materials officer Randy Sawyer assured reporters that there is no harmful benzene in the area.

"Our biggest concern is the particulates," Sawyer said. "We did find some unhealthy levels of particulates last night. When we called an all clear last night, it was in the healthy range for particulates ... We're not expecting any long-term health impacts from the fire."

Officials continue to say they cannot confirm any connection to Monday night's 4.5 magnitude earthquake, centered near Pleasant Hill.

That quake caused malfunctions at two nearby oil refineries operated by Shell and Marathon oil, Sawyer told KQED previously.

"Anything related to the earthquakes as a cause to the fire would be speculation at this point," Hill said.

Update, Wednesday, 9 a.m.

Contra Costa County Fire Protection District spokesman Steve Hill said Wednesday morning during a press conference that the fire at the NuStar Energy storage facility in Crockett has been extinguished and firefighters are working to make sure it will not flare up again.

He said Contra Costa County Fire is leading the investigation into the blaze, but said it was far too early to know the fire's cause.

Two storage containers that held ethanol burned almost entirely, Hill said. The ethanol is now being held in place by dirt berms and foam blankets.

Hill said an assessment team was at the facility looking for ways to remove the ethanol and to mitigate problems with vapors.

Hill also said a Chevron firefighter sustained minor injuries overnight related to the heat of the blaze, but was treated by Chevron and released.

The large blaze at the NuStar facility Tuesday led to a shelter-in-place order from about 2 p.m. until about 9:30 p.m. in parts of Contra Costa County. It also forced the closure of I-80 from Highway 4 in Hercules north across the Carquinez Bridge to I-780 in Vallejo for nearly seven hours, snarling traffic throughout the Bay Area.

All John Swett Unified School District schools will be closed on Wednesday due to the extended shelter-in-place in the Crockett/Rodeo communities, according to the Contra Costa County Office of Education. Class is canceled Wednesday for the Golden Gate Community School in Rodeo.

Original Post: Updated Tuesday, 11 p.m.:

A large explosion and fire at a NuStar Energy storage facility in Crockett on Tuesday afternoon resulted in a shelter-in-place order for some Contra Costa County residents, from just north of Hercules along the I-80 corridor to Crockett. The order included residents of both Rodeo and Crockett.

The Contra Costa County Sheriff's Office issued the order shortly after 2 p.m. — it was lifted around 9:30 p.m.

Residents in the affected area were advised to go inside, close all windows and doors, cover any cracks around doors or windows with tape or damp towels, and turn off all air conditioners, heaters and fans.

The fire began around 2 p.m. Tuesday and was pushing smoke eastward into the Central Valley, according to Kristine Roselius with the Bay Area Air Quality Management District.

The Air District issued an air quality advisory shortly before 5 p.m. for smoke east of Rodeo along the Carquinez Strait, including Benicia, Martinez, Baypoint, Pittsburg and areas to the East.

I-80 was closed in both directions from Highway 4 in Hercules north across the Carquinez Bridge to I-780 in Vallejo, snarling traffic across the Bay Area. The closure was expected to last until midnight, but the freeway reopened earlier, just before 9:45 p.m.

Two large storage tanks burned at the NuStar facility, according to Contra Costa County fire officials and NuStar.

Firefighters were using foam and water to attack the flames and cool adjacent storage tanks.

One of the tanks is believed to contain ethanol, while another is believed to have been empty, county officials said in a press release.

Footage of the second tank exploding can be seen at the 13-second mark of this video, provided to Vallejo fire officials:

A California Division of Occupational Safety and Health (Cal/OSHA) spokesman confirmed a worker was trapped during the fire and had to be rescued by fire crews.

Local officials and Cal/OSHA have not received any other reports of injuries.

In an emailed press release, NuStar said all its personnel are "safe and accounted for," and that the company is working with first responders.

"[The tanks] were holding very low volumes of ethanol — less than 1% of tank capacity," the release stated.

NuStar Energy LP is a subsidiary of NuStar Energy, based in San Antonio, Texas. That parent company has been fined dozens of times for environmental and railroad safety violations. In 2010, the company paid $450,000 to settle federal Clean Water Act violations.

"This explosion is yet another unmistakable sign of how dangerous oil facilities are to people living around them," said Hollin Kretzmann, a Center for Biological Diversity attorney who works on oil issues. "It's time for California to stop accepting this industry’s explosions, oil spills and everyday pollution of our air and water."

NuStar's Crockett facility is located at 90 San Pablo Ave., north of I-80 and just northeast of the Phillips 66 refinery in Rodeo.

Phillips 66 refinery personnel were assisting in a mutual aid response, said spokesperson Adrienne Ursino in an email to KQED.

"The safety of the community, the environment and our responders are of the utmost importance," Ursino said. She also noted there have been no impacts to Phillips 66 employees or operations.

Hazardous materials staff and firefighters were responding and conducting air monitoring on-site.

Cal Fire crews were also responding to a 15-acre brush fire touched off by the NuStar tank fire. As of 6:30 p.m., that fire was 75% contained.

Officials said they did not immediately know the cause of the fire and whether there was any connection to Monday night's 4.5 magnitude earthquake, centered near Pleasant Hill.

That quake caused malfunctions at two nearby oil refineries operated by Shell and Marathon oil, Randy Sawyer, Contra Costa County's chief environmental health and hazardous materials officer, told KQED.

This post includes reporting by KQED's Ted Goldberg, Sonja Hutson and Lisa Pickoff-White.