The Middlefield, Ellis, Whisman Superfund site, named for the surrounding streets, includes the area around Moffett Federal Airfield. Middlefield, Ellis, Whisman, or M-E-W, is one of many Superfund sites near active or former military bases. M-E-W also contains factories that produced semi-conductors in the 1980s.
The M-E-W Superfund site has air and water contamination from PCE, TCE, and vinyl chloride; chemicals shown to cause cancer. TCE, or trichloroethylene, was used to clean military airplanes and metal fittings during the 1960s, 70s, and 80s.
In April 2012, the Cancer Prevention Institute of California requested testing to be done by the EPA following increased rates of cancer in the area surrounding M-E-W between 1996 and 2005.
The EPA had missed areas outside of the main M-E-W site containing higher than allowable levels of TCE. Groundwater supplies in the area, twenty commercial buildings, and over a dozen homes were on top of hot spot areas, unsafe by EPA standards.
The M-E-W Superfund site will take several decades to clean up. In the meantime, the EPA has installed sensors and ventilation systems to reduce TCE vapors from the air.