Contractor removes 650+ pounds of contamination from Hanford groundwater

RICHLAND, Wash. – For a second year in a row and four months ahead of schedule, the U.S. Department of Energy’s Richland Operations Office (DOE) and contractor CH2M HILL Plateau Remediation Company (CH2M HILL) exceeded the agency’s annual goal for removing hexavalent chromium from groundwater near the Columbia River at the Hanford site in southeast Washington state.

Between October 2013 and the end of July 2014, CH2M HILL removed approximately 680 pounds (309 kilograms) of the contaminant hexavalent chromium from Hanford’s groundwater. DOE’s goal was to remove approximately 550 pounds (250 kilograms) by the end of the fiscal year on September 30, 2014.

“Our contractor removed more chromium than forecasted this year by pulling more groundwater from the areas of highest contamination,” said DOE Richland’s Soil and Groundwater Division Director Briant Charboneau. “Having extraction wells in the right place and adding new treatment systems over the past few years has been critical to our success in removing contamination from groundwater and protecting the Columbia River.”

The chromium contamination resulted from intentional and unintentional releases of chemicals from the site’s plutonium production reactors into the soil along the river. Much of the contaminated soil has been removed, and CH2M HILL is operating treatment facilities along the river to address the remaining chromium contamination in groundwater.

“Through our workers’ efforts to maintain safe and optimum operations of our treatment technologies, we have been able to surpass DOE’s groundwater cleanup goals again this year, and that progress is visible,” said Mark Cherry, CH2M HILL acting vice president of the Soil and Groundwater Remediation Project.

To remove the chromium contamination, CH2M HILL operates five groundwater treatment systems supported by a network of approximately 150 wells. Contaminated groundwater is extracted through the wells and transferred to facilities for treatment. The treated water is injected back into the aquifer to help drive the contaminated groundwater toward the extraction wells. As cleanup progresses, CH2M HILL monitors performance of the wells and installs new wells as necessary to follow the areas of contamination as they shrink.

Altogether, DOE – through its Hanford contractors – has removed nearly 3 tons of chromium from groundwater since treatment systems for removing hexavalent chromium began operations in the mid-1990s.