The discovery of high levels of the toxic chemical perchlorate on a troubled parcel in Santa Clarita may lead to the source of contamination that shut down five drinking water wells in the area, according to an official with the state Department of Toxic Substances Control.
Perchlorate, a byproduct of rocket fuel that has been linked to thyroid problems in humans, has been known to exist for years at the site, once home to a munitions factory.
But recent studies at a test well on the property by the U.S. Army Corps of Engineers show perchlorate levels at 58,000 parts per billion -- the highest levels found there yet, said Sara Amir, the chief of Southern California cleanup operations for the toxic substances department.
Although the state has set a preliminary public health goal of two to six parts per billion for perchlorate, Amir said Santa Clarita residents should not be worried about their health since no one receives drinking water from the site.
Rather, the discovery in an area where perchlorate was disposed of years ago may reveal the origin of an underground plume of the chemical, Amir said.
"We were not surprised that we found the high levels," Amir said. "What it indicates is that we are very close in finding the source of perchlorate on this site."
Amir said she believes contamination by the Whittaker Corp., a munitions manufacturer, could be one source of the perchlorate found in five municipal water wells between 1997 and 2002. She also said more investigation must be conducted by the Army Corps -- and that other sources have not been ruled out.
The most recent findings have done little to resolve a civil legal dispute over the source of the perchlorate in the closed wells. The local water companies that operate the wells believe the munitions company is the source. They are suing Whittaker to force the firm to pay cleanup costs, estimated at $50 million to $100 million, said Mary Lou Cotton, spokeswoman for the Castaic Lake Water Agency, whose subsidiary, the Santa Clarita Water Co., owns three of the five wells.
On Monday, Cotton said the new findings can only help the water agency's cause. "It's hard to deny there's pollution there at this point," she said.
But Eric Lardiere, general counsel for Whittaker, said similar tests conducted closer to four of the closed wells showed very little perchlorate. The sampling results, he said, "do not support the claim that this site is the source of contamination found in the water purveyors' wells."
The Army Corps plans to finish its study of the perchlorate contamination, both on the Whittaker property and the surrounding areas, by late 2003 or early 2004, said Eddie Ireifej, an Army Corps project manager. Half the cost of the study is being paid by the Castaic Lake Water Agency.
Nationally, concerns about perchlorate have become more widespread as experts learned of its health effects on pregnant women and young children. Last month, scientists hired by an environmental group found perchlorate in four heads of lettuce purchased in California supermarkets. State and federal officials are now working to set a definitive perchlorate health standard.
The presence of the chemical also has caused numerous problems in the fast-growing suburban city of Santa Clarita. City government has been negotiating with developers offering to clean up the Whittaker land, which contains other toxic substances and, possibly, unexploded ordnance, according to state and federal officials.
According to Planning Director Jeffrey Lambert, an agreement with developer Santa Clarita LLC seems to be falling apart. Last week, the City Council ruled the company was not in compliance with an agreement to take over the cleanup responsibility agreement with Whittaker. The city is now working on a new agreement with North Carolina-based Cherokee Investment Partners.
Some critics, concerned that growth in the Santa Clarita Valley is outstripping water supplies, have also used the presence of perchlorate to challenge local water agencies' claims about the amount of water available to developers.
In a 2001 lawsuit, environmental groups and Ventura County, which is concerned about development just across its border, challenged local water projections as too rosy, in part because some water is contaminated with perchlorate. The challenge was rejected in February by Kern County Superior Court Judge Richard Oberholzer.