By Melissa Pamer, L.A. Daily News
The U.S. Environmental Protection Agency will drill about 30 new wells deep below the San Fernando Valley next month to better define a toxic underground chemical plume that regulators admit they still don’t understand.
The EPA will install the groundwater wells to monitor for chromium-6, or hexavalent chromium, the metal pollutant that environmental crusader Erin Brockovich famously helped expose in Hinkley.
At a cost of more than $3 million, the new wells are intended to give EPA scientists an improved understanding of where hexavalent chromium can be found – with the intent of guiding future cleanup efforts.
“We just don’t understand where all of the contamination is. We know there are gaps where there aren’t wells installed. We want to find out whether there is or isn’t contamination,” EPA remedial project manager Lisa Hanusiak said.
The new wells will be 50 to 200 feet deep and will likely be installed on public property so that quarterly monitoring will be easy for the EPA, Hanusiak said. A dozen wells will be installed in Burbank, eight or nine in Glendale and nine or 10 in North Hollywood.
The wells will join hundreds of other monitoring sites in the eastern San Fernando Valley that measure toxins in groundwater, primarily the industrial solvents trichloroethylene and perchloroethylene.
More than three decades after those chemical compounds were found contaminating groundwater here – the environmental legacy of the region’s aerospace industry – there’s still an ongoing question about how to clean the mess up. The contamination prevents the L.A. Department of Water and Power from using much of its groundwater, forcing the utility to buy more expensive imported water.
Some of the groundwater in the eastern San Fernando Valley is treated in plants that strip out industrial solvents, but those facilities are not equipped to treat for chromium, Hanusiak said.
That’s because hexavalent chromium has entered the cleanup picture only recently, as monitoring has gotten more precise – and as the chemical’s association with cancer has become more clear.
Meanwhile, the San Fernando Valley contamination plume is moving very slowly, generally downstream toward the Los Angeles River, Hanusiak said. The wells, she said, will guide efforts to stop that spread.
“It’s a fundamental step in getting to a place to where we can identify a cleanup method for chromium,” Hanusiak said. “We don’t know if it will ever really happen because the problem is so widespread.”
The federal agency plans to release a report by the end of next year that will map out groundwater contamination in the San Fernando Valley. It will include assessments of risks to ecological and human health.
On Tuesday, news of the EPA well plan prompted Los Angeles County Supervisor Michael Antonovich to lash out at federal and state efforts that “lack direction for clean-up and suffer from pathetic bureaucratic inertia.”
Antonovich is frustrated with the delay in establishing federal and state maximum contamination levels for chromium-6, according to Fred Leaf, the supervisor’s senior health policy advisor.
The lack of regulation is in part because the science was unclear whether the chemical caused cancer when ingested. But in 2007, a federal toxicology study showed water contaminated with chromium-6 led to cancerous gastrointestinal tumors in rats and mice.
That in part led the California Office of Environmental Health Hazard Assessment last July to release the nation’s first-ever “public health goal” for chromium-6 in drinking water: 0.02 parts per billion.
The figure indicates a level where hexavalent chromium poses no threat to human health when consumed in drinking water regularly for decades. It will be used over the next few years to help the state Department of Public Health draft chromium-6 standards that water systems across California must meet.