MARTINEZ, Calif. (KGO) -- The Contra Costa County health department is monitoring a possible toxic release at the Martinez Refining Company that happened Tuesday morning.
"At approximately 8:30 a.m. this morning, the Martinez Refining Company had a release of about one minute duration of coke dust," says Nicole Heath, Director of Hazardous Material Programs at Contra Costa Health.
The Martinez refinery processes crude oil into gasoline and jet fuel. It produces enough gas to fill more than 250,000 cars daily.
Coke dust is a byproduct of that process. In large amounts, it can be toxic.
But just how much was released Tuesday morning and how far it spread is still unknown.
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Health officials say they have requested a report from the refinery, which will give them a better indication of how much of this coke dust was released.
"Coke is a material that is mostly made up of carbon and hydrogen. There can also, because of the refining process, be trace metals and other chemicals or constituents inside of this material. And that is the exact reason why we are doing a laboratory analysis," says Heath. "Until we have that information, and until we have that laboratory analysis, I can't really speak further to potential health impacts or quantify the release," says Heath.
Tuesday afternoon, a team was out collecting samples in areas that may have been impacted. Some Martinez residents, who live near the refinery, did see small amounts of the black ash on their cars.
Still, at this point, health officials believe the health risks may be limited.
"There is background trace metals, in general, in the environment. But if there is more trace metals than expected, or other substances, than there are potential health impacts," explains Sofe Mekuria, Deputy Health Officer for Contra Costa Health. "But just kind of washing it off with water, we don't expect it would disrupt the material to cause inhalation and that should be fine in terms of potential impacts."
But as the ABC7 News I-Team reported, there was a release on Thanksgiving day last year, in a different part of the refinery. As much as 24 tons of ash rained down on cars and homes. The FBI and Environmental Protection Agency (EPA) are investigating that incident.
United States Congressman John Garamendi, who represents this part of Contra Costa County, says this repeat pattern is a big concern.
"This particular refinery is establishing a very, very bad record. Within one year, nine months, there have been two major releases from the refinery, which tells me, they've got an operational problem. They've got a safety problem. And they absolutely have to address it," says Garamendi.
The refinery did put out a very short statement to warn the community about the release and how to report any problems.
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The Martinez Refining Company released a statement writing:
"This morning the refinery experienced a brief release of Coke dust. We have issued a Community Warning System Level 1 notification, and our refinery personnel are conducting community monitoring. We have also notified appropriate agencies and apologize for any inconvenience this may have caused our neighbors.
If you have a claim or concern related to this morning's release of Coke dust, or would like to speak with a company representative, please call our claims representative at 800-542-7113 and leave the following information:
Full Name, Complete Address, Telephone Number, Email address."
In an email to ABC7 News, the FBI declined to comment on this incident. The EPA wrote, "EPA is aware of this release and is continuing to monitor the situation as the Contra County Health Hazardous Materials team and the Bay Area Air Quality Management District investigate this incident
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