Environmental Success: Accelerating Clean Up

SLAC's Environmental Restoration Group, a part of the Environment, Safety and Health (ES&H) Division, recently completed the installation and startup of an upgrade to the existing groundwater treatment and hydraulic containment system near the SLAC Paint Shop. This work, which was funded by Department of Energy's Office of Environmental Management, was previously announced in a January 2007 SLAC Today article.

The upgrade included the installation of a dual-phase extraction system that simultaneously extracts chemicals via both soil vapor and groundwater. The residual chemicals in the soil and groundwater near the Paint Shop originate from past leaks from a since-removed underground tank that held spent solvents (an accepted storage method at the time).

IIn addition, three new extraction wells were installed and the existing extraction wells and treatment system were retrofitted to accommodate vacuum application as part of the upgrade work. The application of a vacuum at the wellhead allows for the extraction of chemical-containing vapors residing within available soil pore spaces. It also increases the rate at which groundwater can be extracted and treated.

The original groundwater extraction system, constructed in 2001, was installed primarily to contain the contaminated groundwater plume and prevent its migration. This resulted not only in the successful containment of the plume, but also caused the plume to shrink. The upgraded system will shrink it even more rapidly, and with the addition of soil vapor extraction, the chemical mass removal rate has quadrupled.

So far, operation of the original and upgraded system has removed more than 600 pounds of chemicals from the subsurface and treated more than half a million gallons of groundwater.

"We're accelerating the removal process," Project Manager Elizabeth Dahlen said. "This project represents a significant accomplishment for the Department of Energy, SLAC and Stanford University."

—Matt Cunningham, SLAC Today, April 15, 2008

Above image: Dwight Harbaugh, a member of the Environmental Restoration group, collects operating data.

Handy Links

SLAC News Center

SLAC Today

SLAC News

Lab News

SLAC Links

Stanford

Around the Bay

Environmental Success: Accelerating Clean Up



Handy Links SLAC News Center News Center home page SLAC Today SLAC Today Subscribe Archives: Feb 2006-May 20, 2011 Archives: May 23, 2011 and later Submit Feedback or Story Ideas About SLAC Today SLAC News SSRL Headlines symmetry magazine TIP Archives Lab News Interactions Lightsources.org ILC NewsLine Int'l Science Grid This Week Fermilab Today Berkeley Lab News @brookhaven TODAY DOE Pulse CERN Courier DESY inForm US / LHC SLAC Links Emergency Safety Policy Repository Site Entry Form Site Maps M & O Review Computing Status & Calendar SLAC Colloquium SLACspeak SLACspace SLAC Logo Café Menu Flea Market Web E-mail Marguerite Shuttle Discount Commuter Passes Award Reporting Form SPIRES SciDoc Activity Groups Library Stanford Stanford University Stanford Report Stanford Events Life on Campus Around the Bay Bay Area Traffic Bay Area Weather Caltrain BART	Environmental Success: Accelerating Clean Up SLAC's Environmental Restoration Group, a part of the Environment, Safety and Health (ES&H) Division, recently completed the installation and startup of an upgrade to the existing groundwater treatment and hydraulic containment system near the SLAC Paint Shop. This work, which was funded by Department of Energy's Office of Environmental Management, was previously announced in a January 2007 SLAC Today article. The upgrade included the installation of a dual-phase extraction system that simultaneously extracts chemicals via both soil vapor and groundwater. The residual chemicals in the soil and groundwater near the Paint Shop originate from past leaks from a since-removed underground tank that held spent solvents (an accepted storage method at the time). IIn addition, three new extraction wells were installed and the existing extraction wells and treatment system were retrofitted to accommodate vacuum application as part of the upgrade work. The application of a vacuum at the wellhead allows for the extraction of chemical-containing vapors residing within available soil pore spaces. It also increases the rate at which groundwater can be extracted and treated. The original groundwater extraction system, constructed in 2001, was installed primarily to contain the contaminated groundwater plume and prevent its migration. This resulted not only in the successful containment of the plume, but also caused the plume to shrink. The upgraded system will shrink it even more rapidly, and with the addition of soil vapor extraction, the chemical mass removal rate has quadrupled. So far, operation of the original and upgraded system has removed more than 600 pounds of chemicals from the subsurface and treated more than half a million gallons of groundwater. "We're accelerating the removal process," Project Manager Elizabeth Dahlen said. "This project represents a significant accomplishment for the Department of Energy, SLAC and Stanford University." —Matt Cunningham, SLAC Today, April 15, 2008 Above image: Dwight Harbaugh, a member of the Environmental Restoration group, collects operating data.