LAS VEGAS (CN) - A federal judge approved a $7 million, decade-long plan to clean carcinogenic TCE from groundwater under Las Vegas.
The tetrachloroethylene was dumped by a dry cleaning business. The toxic plume stretches more than a mile underneath central Las Vegas and affects hundreds of homes in some of the city's oldest neighborhoods.
U.S. District Judge Robert Jones approved the cleanup plan on Nov. 9. Former Attorney General Catherine Cortez Masto submitted the state's cleanup plan for approval in March.
A now-closed dry cleaner at the former Maryland Square Shopping Center contaminated the soil with the chemical from 1969 to 2000 . Now the TCE must be removed from groundwater near the Boulevard Mall on Maryland Parkway.
Tetrachloroethylene, also known as perchloroethylene, reached shallow groundwater beneath the dry cleaner and created a plume about 6,000 feet long running mostly north beneath the Boulevard Mall and a residential neighborhood east of the mall.
TCE can cause cancer, Hodgkin's disease, Parkinson's disease, impair the immune system and cause other health problems, according to the Centers for Disease Control. It can intrude homes as vapor and be inhaled.
The state has tested nearby homes and installed mitigation systems to stop the vapors from entering them since 2007.
To remove the plume, the state will install a pump-and-treat system along the east side of the Boulevard Mall to extract water, remove the chemical and return the cleaned water to the groundwater.
The plan places extraction wells along the east side of the Boulevard Mall's parking lot to capture contaminated water before it migrates beneath the nearby residential neighborhood. It will use other methods to remove the vapor, including air sparging and chemical oxidation. Air sparging involves injecting high-pressure air into groundwater, capturing the vapor, cleaning it by vacuum extraction and reinjecting it.
The state plans to start the cleanup by the end of this year and have it fully in place by the end of 2016. It estimates the cleanup will take a decade or more to complete and cost $5.7 million to $7.9 million.
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