A new housing development is going up near Fort Detrick, Maryland, and the Army is considering a series of engineering efforts to protect the homeowners after it contaminated adjacent land throughout much of the 20th century by testing biological weapons.

Many of the homes next to what is known as the Area B section of the base are already built — some of them for sale — and single-family properties are selling for about $640,000, which is roughly the median price for the area. That nearby 399-acre section of Fort Detrick was once a proving ground for the Army’s biological warfare program and used as a disposal site for chemical, medical and radiological waste, according to the Environmental Protection Agency.

Decades ago, the Army was frequently testing biological weapons on the outskirts of the Washington, D.C., area, and those grounds are still heavily contaminated. Fort Detrick served as the center of the Pentagon’s bio-weapon development, until those weapons were outlawed by President Richard Nixon.

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Today, much of the surrounding area in that part of Frederick, Maryland, has contaminated groundwater, among other environmental concerns. Area B is on the EPA’s National Priorities List for Superfund sites, meaning it ranks a top concern for known releases of hazardous substances, contaminants or pollutants, according to the agency.

The upcoming home development on potentially poisoned lands was first reported in the Frederick News-Post. The news outlet reported that new groundwater sampling in May showed “high concentrations of contamination along the southwest fence line of Area B and a nearby residential development that could potentially impact dozens of planned homes.”

The Army is assessing installing technologies similar to radon abatement systems, according to Maria Gallegos, an Army spokesperson.

Those systems can lead to increased electricity bills and generally serve as vents to expel toxic gasses. The Army declined to comment on specific technologies that may be implemented to counter toxic groundwater or vapor emitting from the ground.

The service also declined to comment on whether it will reach out to families that have already purchased homes on land that may have environmental or safety issues.

In the 1940s, Area B was used to test biological weapons — mostly viruses, bacteria and fungi that could potentially be weaponized, including experiments with E. coli, according to the EPA. Testing was also done on phosgene, a gas used as a chemical weapon in World War I — and responsible for some 85,000 deaths at the time — and sterilized samples of the bacteria that causes anthrax were also buried in Area B.

“Test animals were buried in trenches or pits located in Area B after autoclave sterilization,” according to the EPA’s description of the site’s activity.

There was an attempt to decontaminate that area of Fort Detrick in the 1970s, but groundwater testing since the 1990s has continued to find pollution. “Most of the drinking water wells near Fort Detrick have been closed, and affected residents were connected to public water supply,” according to the EPA.

Army Installation Management Command said in a statement that the main environmental concern for the new housing development is trichloroethylene. That chemical compound was also a main pollutant of water at Camp Lejeune in North Carolina for decades, and prolonged exposure can cause kidney cancer among other health complications, according to the National Cancer Institute.

Trichloroethene and tetrachloroethene, two volatile organic compounds, have also been major chemical constituents found during groundwater testing, according to the EPA.

The contamination can potentially impact dozens of new residential real-estate developments in the area, based on internal documentation from the Army Corps of Engineers. Army officials canceled a scheduled Military.com interview with Fort Detrick’s environmental official.

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