Toxic Fluid May Imperil River Water

A chemical leaking from a toxic waste site may threaten the Santa Ana River, a major source of Orange County’s drinking water, and has contaminated a private well, state officials said.

Perchlorate, a component of rocket fuel that can cause thyroid damage, was found to be coming from the state-owned Stringfellow acid pits.

Preliminary test results released last week showed that perchlorate has contaminated a four-by-three-mile area of Riverside County, including a private well in the community of Mira Loma.

“The area has increased significantly over what we originally thought,” said Roman Racca of the state Department of Toxic Substances Control.

Further tests will be done this summer to determine whether the nearby Santa Ana River is at risk, authorities said.

A water analysis three years ago did not turn up any perchlorate there, said William Mills, general manager of the Orange County Water District.

Mills said Saturday that he doubted the leakage would threaten Orange County’s water supply or pose a health risk to residents.

However, perchlorate has been detected in several other public water systems, including those in Redlands, Riverside, Loma Linda, San Bernardino and Corona.

Stringfellow is a closed toxic waste dump in the Riverside suburb of Glen Avon. It received 35 million gallons of hazardous waste from 1956 to 1972.