It is inadvisable and unconscionable, at this time, to rezone the Sares Regis and Raintree Partners Sites, located at 520-592 E. Weddell Ave. and 610 – 630 E. Weddell Ave, Sunnyvale, from commercial to high density residential, given the existing contaminated soil conditions located in a Geological Liquefaction and FEMA Flood Hazard Zone Area that was not disclosed in the East Weddell Projects DEIR. Additionally, there has been limited notification and inadequate disclosure to the nearby residents to warn them of the following significant hazardous impacts.
The East Weddell Projects Draft Environmental Impact Report (DEIR) states (and not limited to):
- Arsenic was identified in soils up to 52 mg/kg, which is above the ESL for residential soils of 0.39 mg/kg, and above the naturally occurring background level, which the report stated was 11 mg/kg (Treadwell & Rollo, 2012)
- Vanadium, was identified at concentrations up to 200 mg/kg, above the ESL of 16 mg/kg and the background concentration of up to 129 mg/kg (Treadwell & Rollo, 2012)
- The groundwater contained petroleum hydrocarbons in the diesel and motor oil range at concentrations of up to 4.6 milligrams per liter (mg/L), above the ESLs of 0.1 mg/L for groundwater that is a potential drinking water source.
- Regulatory agencies do not typically require there mediation of constituents below concentrations that are naturally occurring, as these concentrations are considered to be background for the area
To justify the levels of arsenic exceeding ESL for residential soils thereby increasing the background “base” does not minimize the investigation report that concluded that arsenic and vanadium in soils may present a potential risk to future occupants at the project site and could require remediation (Treadwell & Rollo, 2012) and should be considered inhumane.
This is a dangerous site to build 670 apartment buildings and should not be rezoned to accommodate such usage. Arsenic, a known human carcinogen, is notoriously poisonous to multicellular life, and is a common n-type dopant in semiconductor electronic devices, and the optoelectronic compound gallium arsenide is the most common semiconductor in use after doped silicon. This DEIR does not state the cause of the high levels of arsenic, and proposes to “sweep into a background level” thus exceeding advisable levels acceptable for residential usage.
The DEIR claims the arsenic is “natural” when the area has, indeed, been in use by commercial computer companies? And in fact, registered 610 East Weddell Drive, formerly Analog Devices, for example. This is not “a natural condition” causing justification to raise advisable levels to be classified as “background conditions” and is unacceptable.
Described under “Environmental Setting” the soils at the Raintree site contained arsenic at concentrations up to 52 mg/kg and vanadium at concentrations up to 200 mg/kg. These concentrations are above screening levels for residential land uses, and could potentially pose a risk to construction workers and future residents, who may come into direct contact with those soils. Arsenic is a known human carcinogen (ATSDR, 2007a). Vanadium is associated with lung, gastrointestinal, and neurological effects and is possibly carcinogenic to humans (ATSDR, 2012).
The DEIR recommends as mitigation measure, the placement of a cap consisting of pavement or a layer of clean soils and implementation of an operation and maintenance plan to ensure that the cap is maintained and no maintenance take place affecting the affected soils without proper health and safety precautions.
Have you noticed huge, deep, long cracks in concrete driveways or patios, where one side “depresses and sinks” 4”- 6” lower than it’s adjoining side? This is a common occurrence in liquefaction areas near the bay such as in Milpitas, Alviso, some areas of Sunnyvale when the ground is settling and shifting.
To “cap” does not reasonably seem logical to contain, indefinitely, hazardous toxins that could be dislodged when the soil shifts due to liquefaction. Not only was the geological and soils category omitted from this DEIR, neither is consideration for rising sea levels, as this is near the bay.
The groundwater contained petroleum hydrocarbons in the diesel and motor oil range at concentrations of up to 4.6 milligrams per liter (mg/L), above the ESLs of 0.1 mg/L for groundwater that is a potential drinking water source.
These are serious contaminants, which place the nearby homeowners, residents, workers and renters at serious health risks. This site should not be considered for residential building until the soils has been cleaned up, the notification area has been extended beyond Tasman, and an adequate Environmental Impact Report completed after the soil is free from hazardous contaminates.