Pollutant May Threaten Plans for New Homes

Underground pollutants have stalled plans for 2,500 homes in the fast-growing Santa Clarita Valley and sparked a debate about whether the toxic plume poses a larger threat to water supplies.

In April, ammonium perchlorate, a component of rocket fuel, was discovered in a drinking well a few miles downstream from a former Cold War-era munitions plant.

Studies of laboratory rats have shown that tiny doses of perchlorate can affect the thyroid’s production of hormones that are critical to early childhood development.

The existence of perchlorate in the aquifers under Santa Clarita has been known for years, but the recent discovery marks the first time it has affected home-building in the area.

Environmentalists say the tainted well is further proof that the valley’s water supply cannot keep pace with an ongoing construction boom.

The well is near the proposed site of the 2,500-home West Creek development and the 1,089-unit Riverpark project.

“They say they want to get these wells back online, but they should be cleaning up the source of the pollution first,” said Lynne Plambeck, president of the Santa Clarita Organization for Planning the Environment. “Growth is happening too fast,” she added.

Readings from the tainted well show that ammonium perchlorate levels ranged from 9.8 to 11 parts per billion.

The state suggests a goal of 6 parts per billion, roughly equivalent to six drops of water in a typical residential swimming pool.

Valencia Water Co., which is owned by the Newhall Land and Farming Co., the area’s biggest landowner and developer, immediately shut down the contaminated well and announced plans last month to clean it up.

But residents are concerned that the plume of perchlorate may be spreading west toward other drinking wells, Plambeck said.

“There’s another five municipal wells within about a half mile of this one,” she said. “If it’s spreading that quickly, all these other wells will be impacted too.”

Robert DiPrimio, president of Valencia Water Co., said there was no reason to believe that the plume was rapidly spreading or that it posed a threat to the retailer’s other 22 wells.

He said this was the first time since 1997 that perchlorate had been detected in one of Valencia’s wells, despite repeated testing.

DiPrimio and other water officials believe that a small amount of perchlorate may have migrated to the area after last winter’s heavy rains.

But nearby monitoring wells registered high levels of perchlorate even before the near-record rainfall, according to a study by the Army Corps of Engineers.

The newly discovered tainted well is a few miles from the former Whittaker-Bermite munitions factory, where dynamite, missiles and small rockets were tested until the plant shut down in 1987.

“We’ve always had a concern about our wells downstream from Whittaker-Bermite because of the level of perchlorate up there,” DiPrimio said. “But in eight years we’ve only found one well with any perchlorate in it.”

Environmentalists said the water company was playing down the significance of the tainted well and its effect on future water supplies in north Los Angeles County because of its own interests.

“It seems obvious that Valencia Water may have a special financial interest through its parent companies in stating that this additional closed well will not affect production,” Johanna Zetterberg, conservation coordinator for the Angeles chapter of the Sierra Club, wrote in a May letter to the Santa Clarita City Council.

But DiPrimio said the company’s response had nothing to do with pending development.

Because of the well’s proximity to the former weapons factory, officials have always known that there was a risk of contamination and had a treatment plan in the works in case perchlorate was discovered, he said.

This is not the first time contaminants have been found in the area. The discovery of high levels of perchlorate forced the shutdown of five drinking water wells in central Santa Clarita in 1997 and 2002.

Concerned about the most recent detection, the Los Angeles County Regional Planning Department asked Newhall Land and Farming to submit a supplemental environmental review of its West Creek project.

The request came after the original study was certified by the Board of Supervisors.

The board is scheduled to review the new environmental study next month. The survey found that there is enough water in local aquifers to support the West Creek development without the contaminated well.

West Creek has been stalled by legal challenges since 2000, when Plambeck’s group and others sued Newhall Land. They contended that Newhall’s projections of water availability were overstated and based on faulty data.

Last month, four environmental groups filed a lawsuit to block the Riverpark project, in part to protect against the spread of ammonium perchlorate. The site is across the street from the tainted well.

Newhall officials said the well was never intended to supply drinking water to the development, and asked the Santa Clarita City Council for a two-month delay of its approval until it could be certain that it was safe to proceed.

But plaintiffs in the lawsuit -- including the Sierra Club, Friends of the Santa Clara River and the Center for Biological Diversity -- allege that the council’s approval of the development June 14 ignored their concerns about protecting the county’s last wild river.

The other group, the California Water Impact Network, said its chief worry was the “cumulative stress” placed on local water supplies from increasing development in the Santa Clarita Valley.

“If you build a lot of houses,” said Carolee Krieger, president of the watchdog group, “there’s not going to be enough water.”

Meanwhile, in a settlement with Valencia Water Co. in May, Whittaker-Bermite agreed to pay more than $500,000 to clean up the tainted well, DiPrimio said. Work probably will begin in October.

Negotiations are continuing over cleanup of the area’s other five polluted wells after local water companies sued Whittaker, alleging that it was the source of the contamination.