Toxicologist takes soil samples around Martinez refinery following November chemical release
MARTINEZ -- A toxicologist began taking soil samples Thursday from areas affected by a chemical release from a Martinez oil refinery last year, county health officials reported.
Samples were being taken from more than a dozen sites in Martinez and Benicia where ash was observed and mapped following the November 24, 2022 release of hazardous materials from the Martinez Refining Company (MRC), formerly the Shell Oil refinery.
MRC said the material release was "spent catalyst" comprised primarily of alumina silicate, clay and other minerals mined from the earth. It is referred to as "spent" or "used" catalyst which has been incinerated at high temperatures to remove impurities so the catalyst can be reused.
Following the release, which MRC acknowledged was up to 24 tons of metal dust, residents near the refinery were warned to not consume any produce grown in their yards in case of dangerous contamination.
Last month, Bay Area air quality regulators released a report mapping the areas affected by the dust plume. The Bay Area Air Quality Management District (BAAQMD) compiled the report after Contra Costa Health received multiple inquiries from members of the public concerned about soil contamination.
The purpose of the air district's report was to provide a map for the county to use for its soil sampling program.
Summary Report: Mapping Dust Fallout from the November 2022 MartInez Refining Company Incident
Contra Costa Health said in a press statement Thursday the samples will be analyzed for concentrations of metals that may pose risks to human health through skin contact, inhalation or from consuming produce grown in the contaminated soil.
The lab results of the soil samples are expected in late May or early June.
"We know the community is eager to find out what's in the soil in their yards and whether they should be concerned for their health," said Supervisor Federal Glover in a prepared statement. "The soil testing will help provide residents with answers to those questions."
"Residents affected by this release deserve to know if there is any health risk. Contra Costa Health is working as quickly as possible to ensure that accurate information reaches the public about this issue," said Board of Supervisors Chair John Gioia in a prepared statement.
Gioia also serves on the BAAQMD Board of Directors.
The Contra Costa County District Attorney's Office told KPIX that it was reviewing this case for two violations: failing to report a release or threatened release of hazardous material and releasing illicit discharges to the county's stormwater system. It could take several months for the district attorney's office to reach a charging decision.
KPIX reached out to the Martinez Refining Company when originally filing this report in March. Representatives from MRC declined an on-camera interview but answered questions via email referring us to their original Incident Report.
MRC Incident Report on release of spent catalyst:
After last month's release of the BAAQMD report, KPIX requested a statement from MRC, to which they responded by referencing the report they sent in March.
For more information on the risk assessment and independent investigation of the November 2022 incident, visit cchealth.org/hazmat/mrc.