April 18, 2006 9:20am
• Kern, Fresno, Sacramento named in new study
• Los Angeles most contaminated; Modoc the least
In the Central Valley, Kern, Fresno and Sacramento counties make EDR’s list of the ten most contaminated counties.
Statewide, Los Angeles County ranks as the worst while Modoc County, in extreme northeastern California, has the fewest contamination sites, according to EDR.
Of the ten most populated counties in California, Contra Costa ranks lowest in incidents of contamination
"It's important that people understand that they may be living near significant environmental hazards," says Rob Barber, CEO of Environmental Data Resources, in written comments. "Today, it is a common practice when buying a home to look for hazards like asbestos and radon, but other environmental threats could exist as well, such as leaking underground storage tanks or contaminates effecting soil and groundwater such as perchlorate.”
He says the EDR study suggests that environmental hazards are widespread in the most populated parts of the state.
The study aggregates environmental data from federal, state and local government sources as well as tribal information to rank the counties in the state that have the highest and lowest risk of contamination.
The company says the counties that pose the lowest environmental risk are Modoc, Sierra, Mariposa, Inyo, Tehama, Calaveras, Mono, Trinity, Tuolumne and Colusa. The highest risk counties are Los Angeles, Alameda, San Diego, Santa Clara, Orange, Kern, Riverside, San Bernardino, Fresno and Sacramento.
While the study includes nine different types of environmental hazards that exist in California and almost 36,000 contaminated sites in total, three categories of hazards that are critical to the rankings include:
• Leaking underground storage tanks;
• Perchlorate in drinking wells; and
• State and federal “superfund” sites.
Leaking underground storage tanks are a significant source of contamination, EDR says, and may pose potential threats to health and safety including exposure from impacts to soil and/or groundwater; contamination of drinking water aquifers; contamination of public or private drinking water wells; and inhalation of vapors.
There are currently over 20,665 known leaking underground tanks in California that are awaiting remediation.
Perchlorate can interfere with iodide uptake by the thyroid gland and can lead to a host of development and growth problems. The EDR report says there are 2,212 sites of perchlorate water contamination in California.
Superfund sites are the federal and state governments' programs to clean up uncontrolled hazardous waste sites. Under the Superfund program, abandoned, accidentally spilled, or illegally dumped hazardous waste that pose a current or future threat to human health or the environment are cleaned up. There are currently 428 sites classified in state and federal databases as Superfund sites in California, EDR says.
The county rankings in the study are based on the quantity of identified hazards in each county, which is then weighted by the remediation costs for each type of hazardous site found. The clean up costs are based on estimates and averages from the Federal Environmental Protection Agency. EDR says the costs are an important factor to consider, as the more expensive the cleanup, the more severe the environmental hazard.
EDR, of Milford, Conn., is wholly owned by DMG Information Inc., the business information division of Daily Mail and General Trust PLC, based in London.