Only four of the more than 180 environmental remediation sites physically investigated as part of the Joint Base Lewis-McChord Installation Restoration Program remain open. The program's success in identifying and addressing the potential environmental impacts from past practices earned the installation's environmental restoration team recognition in the recent Secretary of the Army Environmental Awards for its expert management of cleanup activities.
JBLM's installation restoration program is almost finished, with all site restoration already determined, implemented and either underway or completed. Only the Logistics Center closed landfill (known as LF-2) and the American Lake Garden Tract, which are both on the National Priorities list (NPL); a Washington State Department of Ecology agreed order site (known as AOC 9-2); and a consent decree site on McChord Field (known as SS-34N) remain active. Innovative engineering projects converted active NPL site groundwater treatment processes into facilities promoting water and energy conservation, and have resulted in considerable savings at those sites during a period of austere budgets.
Three pump and treat systems address the Logistics Center groundwater remediation and another remediates groundwater at the American Lake Garden Tract. The systems pump groundwater from contaminated aquifers, pass it through air strippers to remove the contamination and return it to the aquifer.
For the American Lake Garden Tract NPL site, the groundwater passes through activated carbon before its return to the aquifer.
At the Fort Lewis agreed order site AOC 9-2, an air sparge/soil vapor extraction system is in place to alleviate gasoline and gasoline vapors in groundwater and soil.
The Site SS-34N remedial action consisted of injecting a non-toxic oxidant into groundwater to chemically break contamination down into harmless products.
Installation restoration program progress at these sites minimizes staffing requirements and resulted in conclusion of the costly scientific studies required as part of site investigations. The remediation team's current focus is optimizing long-term monitoring to further reduce operating costs.
In addition to the cost savings for the remediation program, the three pump and treat systems at the Logistics Center also serve as clean water sources supporting JBLM heating and cooling systems and contribute to the installation's net zero water conservation goals.
The sea-level-aquifer pump and treat system meets the water supply needs of the Madigan Army Medical Center's heating, ventilation and air-conditioning system. It also supports a recent hospital expansion, eliminating the need for a separate water supply system for cooling that facility.
Reconfiguration of one treatment system provides water for ground source heat pumps for two buildings recently constructed on the installation. The heat pumps use 62 percent less energy annually than conventional HVAC systems. This reconfiguration eliminated the need for separate groundwater supply wells and a water delivery system for the new facilities.
The final landfill pump and treat system was reconfigured in 2014 to provide water for ground source heat pumps for an Army Reserve Center constructed nearby.
The three pump and treat systems also serve as a learning tool for others. Observations of the systems, which mitigate contamination resulting from a closed landfill, are part of a Department of Energy pump and treat closure study conducted by Pacific Northwest National Laboratory and completed in 2015. The report provides resources and guidance on conducting assessments of other pump and treat systems.
JBLM's installation restoration team also collaborated with a design engineer to include an air sparge and soil vapor extraction system as part of the construction of a restaurant and bank. This in situ remediation of gasoline-contaminated soil and groundwater enabled building new facilities on a brownfield site currently undergoing remediation, without risk to building occupants or customers.
As recipients of the Secretary of the Army Environmental Award in the team category for environmental restoration, Joint Base Lewis-McChord will represent the Army at the Secretary of Defense Environmental Awards competition later this year.
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