Martinez Refining Company Shares New Findings on Gas Leak and Fire Investigation

On Friday, Martinez Refining Company (MRC) provided an update regarding its ongoing investigation into the February 1 refinery fire, offering insights into the potential health impacts of the smoke that spread across northern Contra Costa County.

The latest report outlines the company’s internal review of the incident, which triggered a temporary shelter-in-place advisory from health and safety officials due to concerns over particulate emissions. MRC’s statement also cautions the community about potential intermittent flaring as refinery units undergo draining and purging processes.

“We are diligently working to determine the root causes of the incident and will implement necessary corrective actions,” the company stated in its press release. Additionally, Contra Costa Health has requested specific information about the substances released or ignited during the event, and MRC aims to submit this data by the February 10, 2025 deadline.

A preliminary 72-hour incident report, released on Wednesday, shed light on the gas leak’s origin and the fire’s cause. Air quality measurements taken during the incident indicated “no significant” levels of harmful pollutants. The leak involved less than 500 pounds of sulfur dioxide, a gas known to cause respiratory irritation and discomfort in the eyes, nose, and throat.

According to the report, the leak began when two employees opened equipment around 1:30 p.m. during routine maintenance preparations, releasing hydrocarbon gas. “The workers immediately evacuated the area, after which the gas ignited, causing a fire that spread locally,” the report detailed.

MRC notified the Bay Area Air Quality Management District at 1:41 p.m. and contacted Contra Costa County Health Services’ Hazardous Materials Program at 1:48 p.m. This prompted a level 2 public health alert, advising sensitive groups to limit outdoor exposure.

By 3:22 p.m., the company had also reached out to Oil Spill Prevention and Response, though specific details from that communication were not disclosed in the report. The U.S. Coast Guard was alerted at 3:53 p.m., deploying six personnel to the refinery’s administrative offices. Roughly an hour later, Contra Costa Health Services escalated the public health warning to a Level 3 shelter-in-place order for neighborhoods north and east of the refinery, activating emergency sirens.

The shelter-in-place directive was lifted around 9:15 p.m., but a health advisory remained in effect through Saturday night. The report did not clarify the reason for the three-hour delay between the fire’s ignition and the shelter-in-place order.

MRC’s Friday update noted that flaring could persist in the coming weeks as the investigation continues. The company also confirmed that all refinery operational units, except essential utility and environmental systems, have been shut down.

“Flares are a critical component of a refinery’s safety infrastructure, designed to manage excess gases and pressure safely through controlled combustion,” MRC emphasized in its statement. “We remain committed to cooperating fully with all agency inspections and investigations.”

Photo credit: city of Martinez. All rights reserved.