Microscopic chemical-eating bugs help DLA clean, protect groundwater

By Stephen J. Baker, DLA Aviation Public Affairs

Some of nature's smallest helpers will be at the frontline of Defense Logistics Agency's continuing work to restore and protect the environment at Defense Supply Center Richmond according to a remediation plan and feasibility study published recently by DLA Installation Support's Environmental Branch in Richmond.

The "OU-7 Proposed Plan and Feasibility Study"– created with support from the U.S. Environmental Protection Agency and the Virginia Department of Environmental Quality (DEQ) – details the upcoming cleanup of a site known as Operable Unit 7, located in the south-central region of the installation.

According to study, the site served as a firefighting training area in the 1960s where flammable liquid chemicals and petroleum products were dumped into three separate and unlined training pits, ignited and extinguished during the training. Those activities, according to the study, are the most likely cause of groundwater degradation beneath the site.

Part of the plan calls for in-situ bioremediation, a passive technology that relies on native microorganisms to decompose contaminants and render them harmless. DLA Environmental Engineer Steven Edlavitch said the system has been pilot-tested at other OUs on the installation with positive results. "These chemical-eating bugs can knock down chemical concentrations by many orders of magnitude," he said.

For the scientifically minded, Edlavitch describes the in-situ bioremediation system as a "permeable reactive treatment wall that creates a reductive dechlorination zone, which treats contaminants in the source zone and also reduces the downgradient plume size and toxicity."

Jimmy Parrish, chief of DLA Installation Support's Environmental Branch in Richmond, said it boils down to this: "These bugs love to eat our contaminants. The hungrier they are, the more that they eat, and the cleaner the groundwater gets."

According to the published plan, in-situ bioremediation involves the addition of a carbon source to the subsurface, which stimulates microorganisms to biodegrade contaminants. It lists food-grade and agricultural materials as suitable carbon sources; including molasses, vegetable oil, whey and bark mulch.

Other remedies included in the plan are land-use controls, long-term monitoring and natural attenuation. The publicly available plan also details the site's background, characterization, risk summary and alternative remedial actions considered.

DLA Installation Support briefed the plan and study to local community members Jan. 31 during a quarterly Restoration Advisory Board meeting, a forum that allows community involvement in environmental cleanup at the installation. The public comment period for the OU-7 Proposed Plan and Feasibility Study ends March 11.

The proposed plan, which details how to submit written comments, and other related documents are available online at www.adminrec.com/Richmond.asp. Hardcopies of the plan are also available at the Central Branch of the Chesterfield County Public Library at 9501 Lori Road.

DSCR has been a Superfund site on the National Priority List since 1987 due to ground water and soil contamination stemming from industrial and maintenance facility operations from the 1940s through the early 1980s. The various cleanup sites on the center were segregated to 13 OUs for cleanup with Defense Environmental Restoration Act funding. Nine of the OU's were identified for soil contamination, three for ground water contamination and one for a decommissioned water treatment system.

The agency's restoration efforts at the Richmond installation have garnered recognition numerous times. Most recently, in August, the installation's E4 status was reaffirmed by the Virginia DEQ after first being accepted into its Virginia Environmental Excellence Program in 2007 at the highest level: "Extraordinary Environmental Enterprise (E4)." Only 31 of the 400-plus VEEP facilities share that distinction. Also, in 2009, DLA received the inaugural Virginia Department of Defense Eagle Award for environmental stewardship at the installation.

"We have creative environmental engineers who work very hard to improve our wildlife habitat throughout the installation.… and environmental protection specialists who have minimized the generation of waste on center while ensuring exemplary environmental compliance,” Parrish said.