MARTINEZ, Calif. -- A toxicologist hired by Contra Costa County began collecting soil samples Thursday to be tested for contaminants related to last year's accidental release of "spent catalyst" from the Martinez Refining Company.
TRC, a Concord-based environmental consulting firm, is collecting samples from 14 locations in the central and western parts of the county to see if they contain elevated levels of certain harmful metals, including aluminum, barium, chromium, nickel, vanadium and zinc.
The samples are coming from areas in and around Martinez, including the Alhambra Valley and Franklin Canyon areas, as well as El Sobrante, Hercules and, in Solano County, Benicia -- all of which were exposed to a 20- to 24-ton plume of spent catalyst dust during the Thanksgiving holiday.
VIDEO: Here's why residents are being warned against eating food grown in soil near Martinez Refinery
"The samples will be collected and sent to a lab where they will be analyzed for metals that could have been associated with the release of spent catalyst and have potential to pose health effects," Nicole Heath, director of Hazardous Materials Programs for Contra Costa Health Services, said during a media briefing Thursday.
Despite the fact that the noxious plume was released almost six months ago, a TRC official said that shouldn't hamper the collection and analysis process, which captures the top six inches of soil for testing.
"We do believe that we're still characterizing and capturing conditions that occurred during that November deposition event," said Laura Trozzolo, who leads TRC's Risk Assessment Practice.
If the tests reveal potentially toxic levels of contaminants in the soil, TRC could go back and collect samples from additional locations, Trozzolo said.
The testing is part of the county's independent investigation into the spent catalyst release, which is being led by the Martinez Refining Company Oversight Committee.
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At the end of the investigation, the committee will decide what steps the refinery should take to make sure nothing similar happens again.
County officials have criticized the company for failing to inform them of the release, which led to a delay in understanding its size and severity.
Health officials said they learned about the release two days after it happened through social media accounts, after which the county formed the MRC Oversight Committee and referred the case to the Contra Costa County District Attorney's Office, which is conducting its own investigation.
Deputy Health Director Matt Kaufmann said the county will seek reimbursement for the entire process.
"The County Health Department will be invoicing the refinery for all costs associated with not only the community risk assessment, but also the incident investigation that's going to take place under the oversight committee," Kaufmann said.
Also, the county's Hazardous Materials Department has been doing a safety inspection at the refinery since February, which should be wrapping up this week.
In the meantime, people are still being advised to not eat fruit and vegetables grown in soil that was potentially contaminated by the release until the test results come back, which could take about a month.
This was only the third time a dust cloud of spent catalyst was released from the refinery, with the other two times happening in the early 2000s, when it was owned by Shell, Heath said.
MRC has set up a claims line for individuals who think they have been impacted by the release: (800) 542-7113.
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