Jump to main content or area navigation.

Contact Us

Pacific Southwest, Region 9: Superfund

Serving Arizona, California, Hawaii, Nevada, the Pacific Islands, and Tribal Nations

Synertek, Inc. (Building 1)

EPA #: CAD990832735

State: California(CA)

County: Santa Clara

City: Santa Clara

Congressional District: 15

Other Names:

Bulletin Board

On 10/13/17, this website will no longer be updated. Site information will be migrated to the new web page at: http://www.epa.gov/superfund/synertek .
EPA appreciates your patience through this transition. If you have questions, please contact EPA staff listed below.

Description and History

NPL Listing History

NPL Status: Final

Proposed Date: 06/24/88

Final Date: 09/01/89

Deleted Date:

In 1974, Synertek Inc. (Synertek) leased the building located at 3050 Coronado Drive in Santa Clara, California (Building No. 1), where it conducted semiconductor manufacturing operations. In 1979, Honeywell acquired Synertek as a wholly owned subsidiary. Synertek manufacturing operations ceased in 1985. Prior to 1985, Synertek constructed and operated two underground tank systems east of the building. One 200-gallon-capacity solvent tank was used for storing solvents between 1976 and 1982 and three former neutralization system tanks were used between 1974 and 1982 as holding tanks. These tanks stored a variety of chemicals, including chlorinated solvents. The tanks leaked volatile organic compounds (VOCs) into the soil. The quantity of solvents released by these tanks and the dates of the releases is unknown. These tanks, along with the affected soils, were removed in 1985. At that time, it was discovered that onsite and offsite groundwater had become contaminated.

Your drinking water is not affected by VOC groundwater contamination from the site. Your drinking water is brought into the City of Santa Clara through the complex infrastructure of the State Water Project, the federal Central Valley Project, and San Francisco’s Hetch Hetchy Reservoir in the Sierra Nevada Mountains, not from groundwater in this area. In addition, Santa Clara’s drinking water is routinely tested to make sure it meets drinking water quality standards.

Top of page

Contaminants and Risks

Contaminated Media
  • Groundwater

Groundwater contains various VOCs which could off-gas from groundwater and enter into indoor air in buildings located above the impacted groundwater. However, a vapor intrusion investigation including indoor air sampling at the on- and off-property buildings, was completed in 2015 which found no evidence of unacceptable vapor intrusion.

Top of page

Who is Involved

This site is being addressed through Federal, State, and potentially responsible parties' actions.

Top of page

Investigation and Cleanup Activities

Initial Actions

In 1985, Synertek removed one 200-gallon-capacity solvent tank and three former neutralization system tanks, along with the affected soils. At that time, it was discovered that onsite and offsite groundwater had become contaminated.

A groundwater pump and treat system became operational in 1987, which extracted groundwater from three onsite wells. Two offsite wells were added to the system in 1988. An air stripping tower treated the extracted groundwater, following which the treated groundwater was then discharged to the storm drain, pursuant to discharge permit. The groundwater pump and treat system operated until 2000.

Since 2001, groundwater monitored natural attenuation has been conducted to show VOC concentrations are decreasing through the natural attenuation process.

In 2011, additional groundwater treatment was initiated onsite using enhanced in situ bioremediation to further reduce VOC concentrations in the groundwater onsite and to enhance natural attenuation processes.

In 2013, an indoor air evaluation was conducted for the onsite building to assess whether site‐related VOCs detected in the shallow groundwater were impacting the indoor air. Based on the results, the vapor intrusion pathway is not complete or significant under current building use. Additional indoor air sampling was requested by EPA in 2014 for one on-site and one off-site building.

Cleanup Ongoing

Groundwater treatment through groundwater pump and treat and subsequent enhanced in situ bioremediation has successfully decreased VOC concentrations in groundwater. The natural breakdown of VOCs in groundwater is also occurring, which will result in meeting the established cleanup goals.

Top of page

Cleanup Results to Date

From 1987 through 2000, a groundwater pump and treat system removed approximately 72 million gallons of groundwater and removed approximately 84 pounds of VOCs. By 2000, the operation had successfully reduced the average concentration of trichloroethene (the main VOC) by over 90 percent. At that time, groundwater extraction had maximized its effectiveness, and per the regulatory approval the system was shut down. The aboveground portion of the groundwater pump and treat system was removed in 2011 at the request of the property owner, and approved by the regulatory agency, to allow additional site commerce.

Since 2001, after the pump and treat system was shut down, and natural breakdown (attenuation) of VOCs in groundwater has been occurring at the site. Progress is monitored semiannually and reported annually. Natural attenuation is reducing mass and preventing plume migration.

In 2011 to expedite cleanup, additional groundwater treatment occurred onsite using enhanced in situ bioremediation to further reduce VOCs in the groundwater. Trichloroethene (the main VOC) in the enhanced in situ bioremediation treatment area is below the groundwater cleanup goals.

The Fourth Five-Year Review Report, completed on September 27, 2012, concluded that the groundwater plume has remained generally stable but a protectiveness determination of the remedy at the Synertek Site could not be made until after a vapor intrusion assessment was completed in the onsite former Synertek building. A vapor intrusion assessment including soil vapor survey was completed in 2013 for the onsite former Synertek building and concluded that the vapor intrusion pathway was not complete or significant under current building use. EPA requested additional indoor air sampling in 2014 with specific requirements for one building on-site and one building off-site. This sampling was completed in 2015 and showed no evidence of unacceptable vapor intrusion at either the on-property or off-property building.

The next Five-Year Review for the Site is in progress.

Top of page

Potentially Responsible Parties

Potentially responsible parties (PRPs) refers to companies that are potentially responsible for generating, transporting, or disposing of the hazardous waste found at the site.

On-line information about the PRPs for the site is not yet available.

Top of page

Documents and Reports

Show details for Community InvolvementCommunity Involvement
Show details for Fact SheetsFact Sheets
Show details for Legal DocumentsLegal Documents
Show details for Records of DecisionRecords of Decision
Show details for Technical DocumentsTechnical Documents

Top of page

Community Involvement

Public Meetings:

Top of page

Public Information Repositories

The public information repositories for the site are at the following locations:

California Regional Water Quality Control Board
1515 Clay Street
Suite 1400
Oakland, CA 94612

The most complete collection of documents is the official EPA site file, maintained at the following location:

Superfund Records Center

Mail Stop SFD-7C

95 Hawthorne Street, Room 403

San Francisco, CA 94105

(415) 820-4700

Enter main lobby of 75 Hawthorne street, go to 4th floor of South Wing Annex.

Additional Links

Top of page


EPA Site Manager
Angela Sandoval
US EPA Region 9
Mail Code SFD
75 Hawthorne Street
San Francisco, CA 94105
EPA Community Involvement Coordinator
Alejandro Diaz
US EPA Region 9
Mail Code SFD
75 Hawthorne Street
San Francisco, CA 94105
EPA Public Information Center
State Contact
David Barr
California Regional Water Quality Control Board
1515 Clay Street
Suite 1400
Oakland, CA 94612
PRP Contact
Benny Dehghi
2525 West 190th Street
Torrance, California
Community Contact
Other Contacts
After Hours (Emergency Response)
(800) 424-8802

Top of page

Jump to main content.