Monterey County Battery Fire Linked to Surge of Heavy Metals in Nature Reserve’s Soil

After a massive fire at a Monterey County energy storage facility this month, scientists at San José State University have found heightened levels of heavy metals in the nearby Elkhorn Slough Reserve, they said Monday.

Unusually high concentrations of nickel, manganese and cobalt were detected in soils within 2 miles of the lithium battery storage site, according to field surveys conducted by the university’s Moss Landing Marine Laboratories, which has monitored the area for years.

Despite initial reports from the U.S. Environmental Protection Agency and local authorities that the Jan. 16 fire did not release toxins, local environmental groups have warned of the potential for dangerous levels of particulate matter and other chemicals and have pushed for more testing of nearby soil and water.

The fire at the storage facility owned by Vistra Corporation, which supplies energy back to the power grid, engulfed about 80% of the building and its 100,000 batteries in flames, sending a dark plume of smoke high into the air for hours.

Dr. Ivano Aiello, the chair of San José State’s Moss Landing Marine Laboratories, said that after the fire, his lab tested the soil in a 2-mile radius of the plant, which is near the Elkhorn Slough estuary. After taking multiple measurements from about 100 locations, his lab observed a hundreds-fold rise in the concentration of the three toxic heavy metals along the top layer of the soil.

Aiello said his team linked the heightened levels to the fire because the concentration of the heavy metals was only elevated in the top millimeters of the soil, indicating that they were recently deposited. The spherical nanoparticles they found are also used in materials for lithium-ion batteries, connecting the contamination to the battery fire, he said.

“They are clearly the type of material from a battery, so you can link directly the occurrence increasing of this toxic heavy metal to the source, which is a battery,” he said. “The line of evidence from a scientific perspective is pretty solid. There’s no other explanation as to why before the concentrations were much lower and now are much higher, and those elements are linked to those nanoparticles.”

The EPA had set up nine monitoring stations to monitor the air for small particulate matter and hydrogen fluoride, a highly toxic gas emitted by lithium-ion battery fires, for the four days after the fire broke out.

Officials said that they did not detect heightened levels of the pollutants, and neither did a company hired by Vistra to detect the same two compounds. A Facebook group of almost 3,000 locals in Monterey and Santa Cruz counties, however, has amassed discussion of headaches, sore throats, nausea and other symptoms that residents believe could be related to the fire.

Michael Polkabla, the principal industrial hygienist with BioMax Environmental, a consulting firm specializing in hazardous materials and industrial hygiene, told KQED last week that the EPA’s air monitoring stations wouldn’t tell the full story because hydrogen fluoride likely wouldn’t be detectable once the plume of smoke was cleared. He also raised the alarm about metals like cobalt, manganese and nickel, along with lithium, and pushed for soil and water testing both at the battery facility and in nearby areas.

Monterey County, which was initially vague about whether it would test water and soil around the power plant, announced Thursday that it would work with the state to collect water, debris and dust samples at and around the Vistra facility. A spokesperson for Vistra said the company “might” test soil “if there are indications around the site that there might be some compounds or constituents that we think need to be tested.” The company did not respond to a request for comment on Monday about what the company’s most recent plans are.

The county said Monday that it was currently analyzing soil and water samples with experts from the California Department of Public Health, state-level EPA and epidemiologists, looking for any potential health concerns and determining next steps. A spokesperson said they hope to provide preliminary results later this week.

“Public health and environmental safety remain our top priorities, and we are committed to providing transparent, science-based updates to the community as we assess the findings in collaboration with our state and federal partners,” the statement reads.

Aiello’s team is also turning to assess the impact of their findings on the Elkhorn Slough, which he said is the second-largest estuary in California and one of the most diverse and essential ecosystems for hundreds of fish and bird species. It acts as a carbon sink and buffer for sea level rise, he told KQED.

“We need to understand exactly how those particles move through the soil, whether they get in the groundwater, whether they’re getting to waterways and how they may move to the food web — from microbes in the sediments to invertebrates in the soils or in the water to fish and mammals,” Aiello said.

“While those particles are interacting with the environment, they will change,” he continued. “The different toxic metals will start reacting with the surroundings, so that will change a molecular form, and they might become bioavailable. That’s something that we need to study.”

Aside from the potential impact on the food chain, it’s also unknown how the heavy metals will affect people who live nearby or were exposed during the fire.

Cobalt has been associated with cardiomyopathy, lung disease and hearing damage, while nickel is categorized as a carcinogen, according to the National Institutes of Health. Manganese can “cause a disorder alike to idiopathic Parkinson’s disease,” the site said, and all three have been known to cause negative effects at the cellular and molecular levels.

KQED’s Dan Brekke contributed to this report.