825 STEWART DR
The former TRW Microwave Superfund Site (TRW Site), part of the “Triple Site†in Sunnyvale, California, is located at 825 Stewart Drive and neighbors multiple other sites, including: the Advanced Micro Devices (AMD) Buildings 901/902 Thompson Place Superfund Site (AMD 901/902 Site), the AMD 915 DeGuine Drive Superfund Site (AMD 915 Site), the Philips Semiconductors Site (Philips Site; formerly Signetics Inc.), which includes the properties at 811 Arques Avenue, 440 North Wolfe Road, and facilities along Stewart Drive, and the Mohawk Laboratories Site. A groundwater plume composed of volatile organic compounds (VOCs), including trichloroethene (TCE), extends from these sites more than a mile north in Sunnyvale to past Highway 101. The TRW Site, together with three other operable units (OUs), was covered by a 1991 Record of Decision (ROD) for the Triple Site, all located in Sunnyvale. The four OUs for the Triple Site are as follows: (1) The AMD 901/902 Site OU; (2) The Philips Site OU; (3) The TRW Microwave Site OU; and (4) The Companies Offsite Operable Unit (OOU), a commingled plume of contaminants which originated from the other three operable units (and has contributions from other sites in the area). At the time of adoption of the 1991 ROD, the OOU was defined as a 100-acre area, downgradient and north of the Triple Site in an area bounded by the Sunnyvale East Drainage Channel on the west and Santa Paula Avenue on the east, and as the area inside a 5 micrograms per liter (µg/L) isopleth for trichloroethene (TCE) in groundwater. Over 100 residences and at least 4 schools are present within the OOU. The TRW Site was occupied by Aertech Industries from 1968 until it was sold to TRW, Inc (TRW). in 1984. In 1987, TRW sold the facility to FEI Microwave, Inc. In 1993 FEI Microwave stopped production and in 1995 the site was acquired by Stewart Associates and leased to research and development companies until 2001. The exterior of the building was remodeled between 2001 and 2003, including demolition of part of the existing structure and construction of a new two-story building. In December 2002, TRW merged with Northrop Grumman. In 2004, the property was purchased by Pacific Landmark, the current owner (as of 2013). During these changes in site ownership, TRW, and then Northrop Grumman retained responsibility for site cleanup. The primary activity at the TRW Site was assembling and testing microwave components until semiconductor processing began in 1970. Primarily solvents and small quantities of acids were used in the assembly areas for semiconductors. Solvents, acids, and heavy metals were used in the fabrication areas and plating shop. The paint shop used paints and solvents. Groundwater beneath the TRW Site is contaminated with volatile organic compounds (VOCs). Acid rinse water generated by the assembly processes was neutralized on-site and discharged to the City of Sunnyvale sewer system. An underground ammonia gas acid neutralization system was installed when the facility first opened. Floor drains and acid sinks in the plating shop were connected to buried plumbing that carried acid waste to the neutralization system. This system was closed in 1986, and the underground piping was sealed. The system was replaced with three aboveground tanks. Spent solvents were stored in one of four on-site underground tanks. After 1982, solvents were stored in drums and transported off-site. The closest residence is located approximately 1,200 feet north of the site. Municipal wells for the cities of Santa Clara and Mountain View tap a deep aquifer as a drinking water source that has not been affected by the contamination.
20,814 |
People living within a 1 mile radius |
$109,183 |
Average Income |
7,161 |
Occupied homes |
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