EPA Superfund Site

FAIRCHILD SEMICONDUCTOR CORP. (MOUNTAIN VIEW PLANT)

CA | EPA ID CAD095989778

About this site’s exposure pathways: As of September 2023, there is currently insufficient information available to determine the Site-wide Human Exposure Control status at the Fairchild Semiconductor-Mountain View Superfund Site because EPA found that shallow groundwater contaminated with trichloroethene (TCE) and other Site volatile organic compounds (VOCs) may be infiltrating into the sanitary sewer lines and TCE vapors may be migrating along sewer laterals and entering sewer clean-outs and into buildings and bypassing the vapor intrusion remedy in place. EPA's main concern is whether TCE from Site measured in indoor air pose an unacceptable risk of short-term and chronic health effects due to TCE inhalation exposure. EPA has been implementing the 2010 vapor intrusion remedy to address buildings where elevated TCE and PCE concentrations have been found in indoor air. All nonresidential buildings overlying the shallow TCE groundwater contamination have been sampled to determine the appropriate response action and vapor intrusion control systems have been installed in all new buildings in the vapor intrusion study area. A Site-wide Shallow Zone Feasibility Study is currently underway to establish a framework and evaluate alternative groundwater cleanup technologies to address the source of vapor intrusion. The activities planned to make the Human Exposure Control determination include completion of the sewer pathway and building specific evaluations, where necessary, and implementing any necessary response actions.