State Health Proposal Could Shut Down Some Valley Water Wells

A proposal to slash allowable levels of a possible cancer-causing chemical in drinking water has local officials worried that widespread underground traces of the compound--hexavalent chromium--may result in the closing of some city water wells in the San Fernando Valley.

The compound is assumed to have entered the ground water from spills and leaks at shops and factories. Years ago, it was found to have caused stomach cancer in laboratory animals in high doses, said George Alexeef, deputy director of scientific affairs at the state Office of Environmental Health Hazard Assessment.

The agency recently began reviewing all drinking water contaminant rules, a process that has yielded more than two dozen recommendations for changes, including that rules for hexavalent chromium be tightened considerably.

If the proposal is adopted it might render “a significant number” of city water wells illegal at the stroke of a pen, said Mel Blevins, water master for the San Fernando Valley, a court-appointed position responsible for the overseeing of local water supplies.

Blevins is seeking money from federal authorities to pay for more studies of the compound’s presence in ground water.

After tests revealed high levels of some solvents underground in the early 1980s, the San Fernando Valley’s ground water was declared a federal Superfund site. Pumping and cleaning portions of the ground water, paid for in large part by one of the area’s largest polluters, Lockheed Co., is expected to take decades and cost tens of millions of dollars. Planning and construction of treatment plants related to the cleanup continue. Blevins also said he was concerned that ongoing and costly Superfund cleanup processes might be set back if allowable limits on hexavalent chromium were changed.

Los Angeles City Councilman Joel Wachs asked for an investigation Wednesday.

“I don’t have any reason to believe our water supply is anything but safe right now in terms of the water we are drinking,” said Wachs, adding that he drinks tap water.

But he said he was concerned that future ground-water stores were threatened.

The Los Angeles Department of Water and Power distributes drinking water with well below the current maximum allowable contaminant levels for hexavalent chromium, Blevins said. The limit is 50 parts per billion. The recommendation would place the standard at two-tenths of a part per billion, below levels typical in Valley drinking wells.

DWP doesn’t even have the technology to detect levels of hexavalent chromium if concentrations are below about 10 parts per billion, he said.

“I believe this is an unrealistic number,” Blevins said, referring to the proposed health goal. “The water is drinkable. It is not a problem.”

State officials are seeking public comment on the proposed recommendation now, and will make a final decision near the end of the year, he said.

But it is up to the state Department of Health Services to review the recommendation and decide whether to make any changes in current rules. An official said the proposed recommendation for hexavalent chromium levels in drinking water are based on a calculation of what levels would cause one case of cancer in a population of a million people over 70 years.