NORTH L.A. COUNTY — Tests of nearly four dozen water wells in north Los Angeles County have found chromium 6 at levels of up to 17.6 parts per billion, about 90 times above levels recommended by a state health agency, a county study revealed Thursday.
Chromium 6, a suspected carcinogen, was found in 32 of 44 wells tested. Some of them had chromium 6 levels nearly twice those found in a survey of tap water at county facilities last month.
"These are the highest levels of chromium 6 our lab has found so far, and I didn't expect it," said Wasfy Shindy, director of the county's environmental toxicology bureau. "We ought to either clean up the wells or shut them down altogether."
All of the wells are operated by the county Department of Public Works. They supply drinking water to Palmdale, Lancaster, Littlerock and other communities.
The county has no immediate plans to shut the wells, because they do not exceed state standards for total chromium of 50 ppb, said public works spokesman Ken Pellman.
Pellman said about 44,000 homes and business in northern L.A. County received water from the tested wells. But he said chromium 6 levels in the tap water could be lower than the amounts found in the wells, because the well water may be blended with other water sources.
The highest levels were recorded in four wells in Lancaster, including 17.6 ppb of chromium 6 in a well at 1701 W. Avenue H-8.
County Supervisor Mike Antonovich said the tests point to the need for "an aggressive action plan to protect our water supply."
He said he would introduce a motion calling for county officials to report back within 30 days with a plan to remove carcinogens and other impurities from the water and to examine the impact of limiting or closing wells.