Where Will the Lead Go?

Where Will the Lead Go?

Cleanup continues at David Taylor.

For years, bullets rained into the dirt floor 30 feet underground in a shooting range. Now officials at Carderock Naval Surface Warfare Center are looking for a way to contain the lead contamination.

Burton Gray expressed concern that the lead might seep into the soil. “Is there any possibility that the lead would leech down below?” he asked.

Gray was one of the community members of the Restoration Advisory Board, a group providing community input into the cleanup of some contaminated sites at the Carderock Naval Surface Warfare Center, also known as the David Taylor Model Basin.

Three sites are currently under discussion. One had been used as a debris fill site and one as a sewage disposal plant. At these two sites, the Navy has proposed removing the soil from the property.

The third site generated questions from the residents. Under what is known as Building 18, which is toward the western end of the property, there had been a pistol range. It has not been used as a pistol range for at least 10 years, said Bill Spicer of the Center. The range, about 30 feet below the ground level, had a dirt floor.

Since bullets have a high lead content, there is now a high level of lead on that dirt floor.

“The lead levels in that soil need to be addressed,” said Andrew Gutberlet, installation restoration project manager. Gutberlet estimated that the lead levels were 10-20 times normal levels of lead found in soil.

There is a sump pump near the pistol range, but the Navy has not determined whether the water that is being pumped comes from the ground or from nearby water storage tanks.

Gutberlet said that the Navy’s first choice for remediation is to pour concrete over the floor of the pistol range. This technique would avoid tracking contaminated soils up through the building and would be more cost-effective.

Gutberlet said that capping it off would permit no chance of rainwater falling on the soil, and the lead will not have the chance to seep into the water supply.

“Lead does not dissolve well in water,” Gutberlet said.

Others were not convinced that the cap was the best idea.

Patricia Gamby of the Washington Aqueduct joined Gray in suggesting that the Navy analyze the possibility of the water table coming up from under the former pistol range and absorbing the lead.

“Gosh, I’d hate to put a concrete cap on it when you have access to it,” said Gamby. “I’m just suggesting you look at the hydrology.”

“Why wouldn’t, at some point, the groundwater rise to that level?” Gray asked.

Another reason for simply putting the cap on, is that it would prevent a problem in the future.

If the Navy were to divest itself of the property, the building would likely be demolished. Any future construction would probably not go down 30 feet, even if a basement was included, Gutberlet reasoned.

However some options might go that deep. “Obviously, when you build a high-rise, you go down 30 feet,” said Harold Dye, administrator of the hazardous waste program for the Maryland Department of the Environment.

Current zoning laws would not allow a high-rise to be built anywhere in Potomac, but any possible future land use should be taken into consideration, Dye said. “What institutional control do you maintain? Is there a deed restriction? What is there to inform future owners?”

There will be no mention of it on future records, said Gutberlet.

Gutberlet said that a final decision has not yet been made with regard to the pistol range, and that the Navy will listen to the concerns of the community before it commits to a strategy.