More wells found to be contaminated: Investigation continues into drinking water in Tahoe Meadows subdivision
News | September 3, 2007
Adam Jensen
Three more private drinking-water wells in the Tahoe Meadows subdivision were found to contain tetrachloroethylene (PCE) on Monday.
Five parts per billion is the drinking water standard for PCE, a chemical component found in dry-cleaning products and a potential health hazard. One of the three wells contained 8.6 parts per billion PCE.
Another one of the three wells with water containing PCE was also found to have freon levels falling within the range considered safe to drink, according to Chuck Curtis, supervising engineer with the Lahontan Regional Water Quality Control Board. The colorless, nonflammable liquid is used as a coolant in commercial and industrial air conditioners.
Two other wells were discovered to have "very low levels" of chloroform, Curtis said. The chemical was once used as an anesthetic, but is now primarily an intermediate in the production of other chemicals.
These results are from water tested from approximately 12 private wells on Saturday. The lab results from another 25 wells tested on Sunday and Monday are expected back on Wednesday.
Contamination is concentrated in the northeast corner of the subdivision, according to Curtis. Several wells in the area of the contaminated wells, but deeper, have been found to be free of the contaminants.
"Preliminary evaluation indicates the contamination is relatively shallow, based on those couple of wells that did not have contamination," Curtis said Monday.
The subdivision is about one mile west of Stateline along Lake Tahoe's shore and contains approximately 85 private wells, Curtis said.
Water in two wells in the subdivision were determined to have PCE and methyl tertiary butyl ether (MTBE), a gasoline additive, on Friday. The wells were checked after a complaint about foul-tasting water at a home in the subdivision.
Investigation into the source of the contamination remains in its initial stages, with Lahontan Regional Water Quality Control Board looking at current and historic land uses in the area that may have caused the contamination.
"Certainly the groundwater flows downhill toward the lake. We'll be looking uphill from (contaminated wells)," Curtis said. "We'll also be looking at data from sampling that has been conducted in the past."
Drinking water provided through South Tahoe Public Utility District remains unaffected by the contamination in Tahoe Meadows.