06 Feb Martinez Refinery Files Report Saying Contaminant Levels From Fire Were Low

A fire Saturday at the Martinez refinery injured six workers and prompted shelter-in-place and public health warnings. (Tony Hicks / Bay City News)

By Tony Hicks
Bay City News

Martinez Refining Company filed a required preliminary report with Contra Costa Health on Wednesday afternoon about last weekend’s refinery fire, saying air monitoring for contaminants “resulted in no significant levels above background readings.”

The refinery was required to send a 72-hour report to the county health department with preliminary details about the explosion and fire that injured six workers and prompted the county to issue a shelter-in-place order to nearby communities Saturday.

The report also said the refinery conducted ground level and fence line monitoring that found no contaminant levels “above typical background levels” at 32 off-site air monitoring spots.

Under a section of the report titled “Identity of material released and estimated or known quantities,” the refinery indicated less than 500 pounds of sulfur dioxide was released.

According to the U.S. Environmental Protection Agency website, sulfur dioxide can affect both health and the environment. The EPA said short-term exposures to the pollutant can harm the human respiratory system and make breathing difficult. People with asthma, particularly children, are sensitive to the effects of sulfur dioxide.

The report confirmed six injured employees were treated and released.

MRC said it received 18 calls on a community hotline and said the problem began at 1:35 p.m.

Its event summary said, “At approximately 1:30 p.m. on Saturday, February 1, 2025, two workers were opening equipment at the refinery in preparation for planned maintenance on one of the refinery’s process units, which had been shut down on Thursday, January 30, 2025.

“It is currently believed that, while opening the equipment, hydrocarbon material started to leak. The two workers immediately evacuated the area, and the material subsequently caught fire, which spread within the immediate vicinity. Both of those workers were transported offsite for medical evaluation and released,” the report said.

The refinery said it notified the Contra Costa County Community Warning System at 1:48 p.m., resulting in a level 2 warning being sent out. Level 2 indicates the incident has or is expected to go offsite from where the incident initially occurred and may impact health or sensitive populations.

The report said MRC’s fire crews “quickly responded and began suppressing the fire. They called for mutual aid from industry partners and support from Contra Costa Fire Protection District (ConFire). To manage the response, MRC, ConFire, and the Martinez Police Department formed a Unified Command, which allows multiple agencies and organizations to effectively work together.”

The report said, “By approximately 8:30 p.m., the fire had been suppressed to the point the Unified Command transitioned back to MRC, which continues to manage the incident response.”

CCH’s public health director Dr. Ori Tzvieli told the Martinez City Council on Wednesday night that the health impacts of the explosion and fire — which burned until Tuesday afternoon — are still unknown.

“We know that generally smoke from burning hydrocarbons of this type does have toxic chemicals in it,” Tzvieli said. “We still don’t know exactly what was burning. The 72-hour report was not clear on that. So we have asked for clarification from the refinery.”

Tzvieli said he expects to get more details on exactly what burned in the next few days.

“Luckily, the wind was blowing the smoke largely away from the residential areas, so that was lucky. It probably reduced the health impacts,” he said.

Tzvieli said the black smoke that poured from the refinery last weekend typically contains sulfur dioxide, hydrogen sulfide and particulate matter.

“Most of the readings that we had were within normal background range,” Tzvieli said. “We had one or two readings that showed elevated particulate matter that was transient and went away fairly quickly … Beyond that, we’re still waiting to see what was burning.”

Tzvieli said testing will indicate any long-term effects. He said there was some particulate dust that fell in affected areas that is being tested.

“We should know more once we get more clarification from the refinery of what was actually burning,” Tzvieli said. “And I believe they’re still trying to access that area.”

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