Study Finds Traces of 40 chemicals and 20 pesticides pose no health threat!--
U.S. Geologic Survey says.
By Janet Wilson, Times Staff Writer Los Angeles Times,
(Thursday)
It may not taste very good, but it's safe. That's the conclusion reached by U.S. Geological Survey scientists who surveyed drinking water supplies in Orange, Riverside, and San Bernardino counties.
Although trace amounts of nearly 40 industrial chemicals and 20 pesticides were found in groundwater used by 3.5 million people in the Santa Ana River watershed, which covers portions of the three counties, none was in a concentration that poses a danger to the public, officials said.
The geological service sampled 200 wells across the three-county area from 1999 to 2001 and found that more than half contained trace amounts of carcinogens and other dangerous, volatile organic compounds and pesticides.
The study also found that nearly half of wells used for the production of drinking water exceeded standards for dissolved solids, or salty residues, which affect the taste. "While it may not be the best-tasting, the water quality does meet EPA health standards," said Ken Belitz, a USGS hydrologist, and program chief who oversaw the project.
"We definitely know now why Southern Californians drink more bottled water than New Yorkers." Federal scientists, state water-quality monitors, and local water district managers said that although the tiny amounts of toxins detected were not dangerous, they did indicate how widespread human activity in the watershed has been.
"It's a little bit humbling the extent to which human-manufactured compounds are present in deep groundwater," Belitz said. Those toxins include chloroform, industrial solvents, refrigerants, and the gasoline additive MTBE.
Kurt Berchtold, assistant executive officer of the Santa Ana Regional Water Quality Control Board, the regional arm of the state's water regulatory agency, said that with the exception of MTBE, a gasoline additive now being phased out, "those are really the legacy pollutants." "They are in the groundwater as a result of poor historic practices ... rocket testing and a lot of much smaller businesses, especially electronics manufacturers, metal plating factories, and auto shops."
He and others said that in the 1950s and '60s, the dangers of such pollutants were not known. Since then, tough regulatory practices have been instituted. As for the salinity, it is more pronounced in coastal areas, the survey found. Snowmelt from the San Bernardino Mountains provides better-tasting water, but more heavily populated areas in Orange County have water that has been imported or recycled several times through pipe systems.
Ron Wildermuth, head of the Orange County Water District, said that water imported from the Colorado River had high salinity, as did locally recycled water. Overall, he said the average salinity in the Orange County water basin is 465 milligrams per liter, less than the 500-milligram "aesthetic" level set by state law.