Middlefield-Ellis-Whisman (MEW) EPA Superfund Study Area (or MEW Site) is comprised of three Superfund sites Mountain View California

Groundwater Contamination Map Toxic Plumes Map Source: The Chemical Legacy of Old Silicon Valley, NBC Bay Area, Map Editor Scott Pham 2019 https://www.nbcbayarea.com/on-air/as-seen-on/toxic-plumes_-the-dark-side-of-silicon-valley_bay-area/87485/

Envirostor State of California Link: “The EPA added this site to the National Priorities List (NPL) in 1991. This Superfund site is comprised of several former Fairchild Semiconductor Corp facilities spanning 56 acres in Mountain View. The Fairchild Semiconductor Corp – Mountain View site is one of three Superfund or NPL sites that are being cleaned up simultaneously. The other two Superfund sites are the Intel – Mountain View site and the Raytheon site. All three sites are located in the Middlefield-Ellis-Whisman (MEW) Study Area and are being addressed collectively as the MEW SIte. Site investigations at several of these facilities during 1981 and 1982 revealed extensive soil and groundwater contamination, primarily VOCs. Soil cleanup by soil vapor extraction, excavation, and aeration has been completed at all the MEW study area sites. Groundwater remediation is ongoing at the MEW Study Area.”

The contaminants which have been detected in soil and groundwater include trichloroethylene (TCE), trichloroethane (TCA), dichloroethylene (DCE) and chloroform. Continue reading “Middlefield-Ellis-Whisman (MEW) EPA Superfund Study Area (or MEW Site) is comprised of three Superfund sites Mountain View California”


Google HQ Mountain View California

A map made in 2014 by Arcadis that depicts the well locations on the site
Mountainview Voice Article on the TCE Vapor Intrusion with Map that covers the Google Site. https://www.mv-voice.com/news/2018/06/08/epa-sets-sights-on-tce-vapor-intrusion

EPA information on the site

Revision No. 1 to Proposed Groundwater Self-Monitoring Plan (SMP) for the
2018 Annual Monitoring Event for the Spectra-Physics Teledyne Semiconductor
Superfund Site (the Site) comprised of the Former Teledyne Semiconductor and
Former Spectra-Physics Lasers, Inc., Sites Located in Mountain View, California
Groundwater Contamination Map Toxic Plumes Map Source: The Chemical Legacy of Old Silicon Valley, NBC Bay Area, Map Editor Scott Pham 2019 https://www.nbcbayarea.com/on-air/as-seen-on/toxic-plumes_-the-dark-side-of-silicon-valley_bay-area/87485/

The Teledyne property is part of a two-property Superfund site along with the adjacent Spectra-Physics property.

The responsible parties (RPs) for the Teledyne/Spectra-Physics site completed a Monitored Natural Attenuation (MNA) study in the off-property area north of and downgradient of the site. The MNA study concluded that natural breakdown of the chlorinated volatile organic compounds of concern is occuring naturally and at the same rate as groundwater extraction. As a result, only a few of the off-property downgradient extraction wells were operating mainly to maintain hydraulic control of the plume. The RPs completed a pilot study to test the feasibility of enhanced reductive dechlorination (ERD) and concluded that ERD is feasible with bioaugmentation of the Shallow Zone.

Within the last five years, the RPs detected elevated source areas at the Teledyne property using high resolution technology and continuously logged and screened ERD injection well boreholes. Implementing a full-scale ERD treatability study, they have been and are currently remediating the property with groundwater-CVOC levels dropping from as much as over 80,000 ug/l to low multiples of MCLs. Several rounds of ERD injections successfully cleaned up most of the Shallow Zone at the Teledyne property and the adjacent Spring Street residential area to drinking water standards and the treatability study was even more successful in the underlying Upper and Lower Intermediate Zones.

An on-property IA VI evaluation at a SpectraPhysics property in 2004 indicated no IA-CVOC contamination above the Regional Water Board’s 2008 ESLs. More recently, the RPs also assertively evaluated potential IA VI in the off-property commercial North Bayshore and residential Spring Street areas to conclude that IA VI is not occurring in most of the commercial area and is occasionally occurring in several homes in the residential area. The RPs installed sub-slab depressurization systems in the impacted on-property commercial buildings and offered the affected residents crawl space fans to address the issue.

Google Map Reference

Geotracker document explaining the toxic groundwater plume encompassing the Googleplex with maps describing all of the toxic waste sites in the Teledyne/Spectra-Physics site (SL721281224)

Nine indicator chemicals were identified from approximately 30
chemicals detected in the Study Area. The nine indicator chemicals are as follows:
1,1-dichloroethane (1,1-DCA)
1.1-dichloroethylene (1,1-DCE)
1.2-dichloroethylene (1,2-DCE)
tetrachloroethylene (PCE)
1,2,4-trichlorobenzene (1,2,4-TCB)
1,1,1-trichloroethane (1,1,1-TCA)
trichloroethylene (TCE)
vinyl chloride (VC


Geotracker Deed Restrictions for Teledyne/Spectra-Physics site Superfund Site Continue reading “Google HQ Mountain View California”

Google Buildings Polluted With Toxic Vapors From Chemical Spills

Silicon Valley was all abuzz on Friday over news that two of Google‘s buildings on North Whisman Road in Mountain View were suffering from toxic vapors seeping up from the ground below.

Christopher Helman Forbes Staff Feb 23, 2013, 12:21am

Alternative link

I live next to Google – and on top of a toxic site. Don’t let polluters be evil

By Jane Horton, the Guardian Wed 19 Mar 2014 15.45 GMT https://www.theguardian.com/commentisfree/2014/mar/19/google-mountain-view-toxic-waste
“I live across the street from one of Google’s many Mountain View campuses in California. My beloved home – a little farmhouse I bought and moved into with my family in 1975 – now lies above the Middlefield-Ellis-Whisman Superfund Study Area (or MEW Superfund site), an area polluted by 11 Potentially Responsible Parties, well-known, multi-billion-dollar Silicon Valley companies that are possibly to blame “for generating, transporting or disposing of the hazardous waste found at the site”.”

Article explains how a farmer living across the street from Google, where they built stations to remove contaminated groundwater out of the ground and clean it by building silos that mixed the polluted water to air so the vapor could be removed from the water and spread into the neighborhoods.

Alternative Link