EPA Reaches Settlement to Clean California Groundwater
CTS Printex Inc. and ADN Corp. will treat contaminated groundwater in Mountain View, Calif.
The U.S. Environmental Protection Agency (EPA) reached a settlement with CTS Printex Inc. and ADN Corp. to complete the remaining groundwater contamination cleanup at the CTS Printex Inc. Superfund site in Mountain View, Calif.
The companies will spend a total of about $2 million on a system to monitor and treat low levels of contaminated groundwater remaining at the site. They also will monitor the site to ensure that vapor intrusion — a process in which subsurface contaminants volatize and enter the air of overlying buildings — does not impact residents of current or future buildings on the site. This settlement also provides for a reimbursement of $850,000 to EPA for costs it spent on cleanup activities.
CTS Printex and its corporate predecessor, Printex Corp., operated a circuit board manufacturing facility on a portion of the site between 1970 and 1985. Those operations involved the use of various industrial solvents, including trichloroethylene (TCE), which contaminated soil and groundwater on and off the property. ADN Corp. owned the property where the manufacturing facility was located.
A groundwater cleanup system operated for nearly 10 years under the initial cleanup plan, treating more than 100 million gal of groundwater to reduce the size of the TCE groundwater plume. In September 2011, EPA amended the cleanup plan for both groundwater and vapor intrusion. The current remedy restricts groundwater use and requires a building permit review process for new developments to prevent future exposures to site contaminants. In addition, the groundwater remedy incorporates bioremediation and monitored natural attenuation to meet the cleanup standards. The vapor intrusion remedy requires maintenance of current control systems as well as the installation of potential future controls, depending on future land uses.
CTS Printex is one of 23 Superfund sites in Santa Clara County that EPA is currently working on. EPA has worked closely with its state and local partners to address groundwater contaminated by historic releases of chlorinated solvents, primarily TCE, throughout the county, and expand vapor intrusion evaluations and mitigation in residential and commercial buildings.