By Kathryn Reed
Chemicals polluting the groundwater throughout the Lake Tahoe Basin on the California side are keeping engineers working full time.
Most toxins are related to a chemical used in dry cleaning and the now banned fuel additive MTBE.
This building will house equipment to clean up a site. Photo/Kathryn Reed
A temporary structure has been erected behind the Y transit center in the Raley’s shopping center in South Lake Tahoe to house a remediation system.
At this site tetrachloroethylene (PCE) has been found in the groundwater. It came from the laundry facility that used to have a self-serve dry cleaning machine. PCE is a chemical often used in dry cleaning. It has been in the soil at this location since the 1970s.
“As a result of that operation, leaks associated with PCE have contaminated the soil and groundwater,” said Chuck Curtis, supervising engineer at Lahontan.
He said the nearest well belonging to South Tahoe Public Utility District has not operated for years because it was also contaminated by a nearby gas station with MTBE, a fuel additive that has since been banned from Lake Tahoe.
“We have no active wells in the South Y area. We have written that area off for now and the future,” said Dennis Cocking, STPUD spokesman.
Insurance companies for the former property owner and current property owner will foot the bill — which is likely to hit millions of dollars in attorney fees and cleanup costs.
Jim Meredith, who works for the property management firm contracted by property owner Seven Springs Ltd., said they are working with Lahontan to solve the problem.
The current owners of the laundry facility were not the ones who owned it when the leaks occurred.
Lisa Dernbach, senior engineering geologist for Lahontan who is overseeing this project, said, “The contaminated soil and groundwater is mostly outside the front door of the Laundromat. We believe it’s from when they filled up the machine. We think they let the liquid drain out of the hose into the parking lot.”
A new filter and drainage system will be constructed. Air will be injected into the groundwater and a vacuum system used to suck vapors out of the soil. It will take about two years to complete the process. Monitoring will be ongoing and continue one year after the cleanup work is done.
Ski Run situation
In the middle of South Lake is an ongoing cleanup site at the old Moss Chevron Station at Ski Run Boulevard and Highway 50 that is now Lake Tahoe Vacation Resort.
“This (cleanup) started a long time ago, in the ’90s. We were hoping the ozone sparging would be really effective,” Brian Grey, engineering geologist with Lahontan, said. “It’s still years away before we will be looking at closing the case due to the fact they will have to employ another remedial effort out there to reduce the concentrations.”
Because the ozone flushing treatment didn’t work, engineers recently switched to air sparge.
Flushing the system helped with chemicals associated with gasoline, but had no affect on the MTBE, Grey said.
The toxic plume is not near any wells that STPUD owns. The nearest drinking well is in the gated Tahoe Meadows community. Lake Tahoe is the closest body of water that could be affected by the toxic plume.
Grey said extensive monitoring is in place and he doesn’t foresee the toxins reaching the lake.
He said there is a potential threat of vapors from the toxins reaching the hotel. The general manager of the hotel did not return a phone call.
Compounding the situation is contaminated soil excavated from the site was returned to the site.
The cleanup is partially being paid by Chevron, with the bulk being picked up by the state’s underground storage cleanup fund. Money for that fund comes from taxes drivers pay at gas pumps in California.
Grey did not have a dollar amount on what has been spent or what the final cost is projected to be.
Stateline area issues
Several years ago residents in the Tahoe Meadows subdivision complained about the taste of their drinking water. Tests done by Lahontan revealed MTBE and PCE in the water.
Some homeowners are still on private wells, having opted out of the deal to hook into South Tahoe PUD. It is six private wells that are having problems.
Some MTBE in that area long ago was traced to Tahoe Tom’s gas station, according to Cocking.
Grey said the MTBE source is unknown.
“Some think some of the former gas station up there (are responsible), but our samplings don’t show that,” Grey said.
Lahontan is in the process of figuring out where the PCE originated. A dry cleaner used to operate at the Village Center near Stateline.
Terry Hackett, managing general partner for the company that owns the Village Center, said a dry cleaners did not exist when he bought the property in 1980. He said they are working with Lahontan to find the source, but said his company and no lessee of theirs is responsible for the groundwater contamination.
Until the source of the leak is definitively identified and a remediation plan formulated, Tahoe Meadows homeowners with contaminated wells are advised not to drink the water, Grey said. PCE can cause cancer.
These houses are lakefront, which means PCE is also in Lake Tahoe. Even though the state water agency has not tested the lake for PCE in this area, Grey said he does not believe the amounts seeping in pose a problem to humans or fish that swim in the area.
“There are no plans for testing Lake Tahoe,” Grey said.
Other contaminated locations
Dernbach said the most polluted dry cleaning site around the lake is in Kings Beach. A Tahoe City site is also being worked on.
“The problem is there is no state or federal cleanup fund to help them out,” Dernbach said of dry cleaning sites. “We let them drag out a little longer because they can’t afford to pay the cleanup at once.”
MTBE settlement
The nearly $70 million a jury in San Francisco awarded the South Tahoe PUD in 2001 is almost gone. Cocking expects it to be used on MTBE related matters by 2012.
MTBE was first detected in 1996. STPUD sued dozens of oil companies, with Shell and a manufacturer of MTBE the last two to settle.
Cocking said the district’s belief the whole time was, “We didn’t put this in the water, it is going to cost millions of dollars and decades to cleanup, and the ratepayers should not shoulder the cost.”
The board made the decision to not allow any trace of MTBE in drinking water, even though that is stricter than what the law requires.
