Wednesday, January 15, 2014

Cleaning up: Kirkland’s “cleaner than clean” cleanup

By Maura O’Brien, Site Manager, Toxics Cleanup Program and Larry Altose, Communications Manager, Northwest Regional Office, Bellevue

Google II excavation next to Google I, Kirkland WA
Aerial view of Google’s current Kirkland offices, upper left, with the excavation for Google II, lower center.

Technician collects soil sample in the excavated area.
An environmental technician collects a soil sample in the Google II excavation.
Well, this is new. We’ve never had a cleanup like this.

Many property owners work hard to make sure that contaminated sites they own, occupy or purchase meet state cleanup standards.

Until now, no one has told us, "We want to do more" at a site with a completed cleanup that we have already approved.

SRMKII LLC, a property developer, is preparing to construct new offices for Google Corp. in Kirkland, adjacent to Google's existing offices.

SRMKII purchased the five-acre site from Ultra Corp. (formerly Pace National Corp.), which operated a chemical mixing and storage facility from 1971 to 1990. Ultra conducted a cleanup of contaminated soil and water, completed in 2012.

That cleanup removed petroleum hydrocarbons, semi-volatile organic compounds, and chlorinated solvents from soil and groundwater. It made the site ready for redevelopment.

This is a common scenario under Washington's cleanup law, the Model Toxics Control Act, approved by voters in 1988.

Asking for “nothing”

SRMKII has been working, at Google’s request, to ensure the removal of all detectable contamination at the property, even small pockets of chemicals that are below state cleanup levels.

Tied with pre-construction excavation, the company is voluntarily removing "gray soils." These have levels of petroleum, solvents and chemicals that can be detected, but – because of Ultra's earlier cleanup – are below cleanup standards.

Those standards protect human health and the environment. The soil is safe to touch. It doesn’t release vapors. It can’t contaminate water.

SKRMKII began site excavation in Nov. 2013 and has, to date, removed about 11,325 tons of gray soils, about 98 percent of the expected amount.

Making very sure

As a follow-up to Ultra’s original cleanup, Ecology had required two years of groundwater testing – every six months – to verify that one remaining chemical, vinyl chloride, was no longer present. Vinyl chloride forms from the breakdown of solvents. It can mix with water and give off vapors that can rise through the soil.

This monitoring was detecting no vinyl chloride, most of the way through the two years. SRMKII has agreed to re-set the monitoring clock and conduct testing at six-month intervals four more times to confirm that vinyl chloride is no longer present.

This will provide an added measure of reassurance in the residential neighborhoods that adjoin the site.

The Kirkland Google II cleanup is supplemental and voluntary. Ecology appreciates SKRMKII’s diligence in providing this additional safeguard.

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