Glendora city officials are disputing the results of a study that showed higher-than-regulated levels of arsenic in one of the city’s water wells.
The study, commissioned by the Los Angeles County Board of Supervisors and conducted by the Agricultural Commissioner’s Office, examined 195 well water samples across LA County.
Results from the study showed 12 wells containing arsenic levels in excess of the regulated limits, including wells in Glendora, Tujunga, Lancaster and Acton. Saugus had the highest concentration of arsenic at 72 parts per billion.
According to the study, which was conducted between March and September, the Glendora well at 2600 Big Dalton Canyon Road yielded 18.2 ppb of arsenic, above the Health Department’s maximum of 10 ppb.
But officials from Glendora’s public works and water departments say the study yielded a bad sample and that a recent retest of all city water wells came out negative for arsenic.
“When we got the results, we panicked, but we immediately ordered a retest of all the wells,” said Dave Davies, director of public works. He said the new samples from the entire water system in Glendora – including reservoirs and storage units – came out clean.
Glendora Water Department Director Steve Patton said he instantly knew the results were "bogus"
"Contaminated water is typically found near industrial areas. We’re one of the luckey purveyors in the basin," said Patton. "There's no industry above us. All the industry is south of Glendora."
Ken Pellman, spokesman for the Agricultural Commissioner’s Office, said the department cannot vouch for any subsequent tests cities may conduct after the study’s results.
“Our results show the well in Glendora had a high reading of arsenic,” said Pellman. “It wasn’t the highest, but it was higher than the federal limit.”
However, Pellman said he would not consider the results a cause for major concern.
“Well water is typically blended with other water in the system,” said Pellman. “What’s in the well doesn’t equal what residents are getting out of their taps.”
He described 10ppb – the federal limit for arsenic – as an eyedrop of water within an Olympic-sized pool.
Patton said Glendora city officials order tests of water wells for arsenic every three years. Within the last three years only four wells were found to contain less than 3 ppb of arsenic.
The county study also tested for levels of chromium and lead. One well in Castaic was in excess of the federal and state limits of lead of 15 ppb, at 37 ppb.
While the most dangerous form of chromium – chromium 6 – poses a high risk to animal and human health, there is no federal or state limit for that contaminant.
State law limits total chromium at 50 ppb, although no wells in the study were in excess of that number.
However, the study found that there were three times the number of sites in a 2001 study showing levels of detectable total chromium.
Dr. Jonathan Fielding, director of the county’s Department of Public Health, said while the county should continue to monitor levels, he reassured residents should not be alarmed over the results.
“Arsenic and chromium are naturally occurring, so they will always be there to some degree in our water supply,'' Fielding said.
- City News Service contributed to this report.