Cleanup complete at WWI chemical weapons dump in D.C.'s Spring Valley

At the beginning of World War I, the couple dozen students attending American University suddenly found themselves shunted off campus, their classes held at professors' houses, while more than 1,000 chemists and engineers flocked to what was then rural acreage in a sparsely developed corner of the District. Their mission: to develop and test deadly chemical weapons, including mustard gas.

Now, the most contaminated site from that era has been cleaned up, after two decades of work by the Army Corps of Engineers. The site, at 4825 Glenbrook Rd., NW, was one of the locations where chemicals and debris were dumped when the labs were dismantled after the war.

Amidst multi-million-dollar mansions on a leafy street in Spring Valley, the Army Corps set up a massive barn-like structure, 80 ft. long by 60 ft. wide, to prevent chemical agents from escaping while crews wearing full hazmat suits and oxygen tanks excavated the site by hand. At this one property, workers unearthed 556 "munition items," 23 of which were filled with chemical agent, as well as 53 sealed glass containers of chemical agent. They also found and disposed of 2,139 pounds of laboratory debris and 7,500 tons of contaminated soil.

Six different chemical agents used only in warfare were unearthed at the Glenbrook Rd. property, including white phosphorous, arsenic trichloride, and magnesium arsenide. Arsine, a deadly gas, was found weaponized in 75 mm projectiles.

The location of the Glenbrook disposal pit was found with help from an old photo, found in a collection owned by Sgt. C.W. Maurer. On the back of the 1918 photograph, Maurer wrote:

"The Pit, the most feared and respected place in the grounds. The bottles are full of mustard to be destroyed here. In Death Valley. The hole called Hades."

Army Corps spokesperson Cynthia Mitchell says it wasn't unusual, in the early 1900s, to dispose of hazardous materials this way — dumped in disposal pits in remote areas.

"At that time, this was standard practice," says Mitchell.

But in the years since WWI, the area became a posh neighborhood of sprawling homes set amid expansive lawns, many now valued at more than $5 million. This has complicated remediation efforts.

In 2012, in order to conduct the cleanup, the Army Corps demolished a 5,000 sq. ft. house on the Glenbrook property, which at the time was valued at more than $3.3 million, according to city tax records.

"Being able to accomplish this type of work in an area where private properties and a major university campus and public streets are directly in front of the site is extremely challenging," said Mitchell.

The Army Corps structure is now gone, as are the chemical weapons, and the property, owned by American University, is nothing but an innocuous sloping residential lot covered with grass. (Disclosure: American University holds the license to WAMU, which owns DCist).

During WWI, the project was known as the American University Experiment Station, or Camp Leach. Numerous divisions were at work at the site. One division studied the efficacy of toxic compounds already in use in warfare in Europe and also tested hundreds of new substances for possible use, including new types of mustard gas. Another division tested gas masks and other equipment to protect American troops from gas attacks. Yet another division developed and tested explosives, including anti-aircraft weapons. Other divisions tested toxic chemicals on animals, including mice, rats, dogs, cats, guinea pigs, and rabbits.

The existence of underground remnants from the WWI laboratories was discovered in 1993 when a contractor digging a utility trench in Spring Valley found buried ordnance. Since then, 1,632 properties in the neighborhood have been tested for arsenic, which was used in several of the chemical agents. Of those properties, 177 were found to have high levels of arsenic — the Army Corps dug up people's yards, removing the contaminated soil. Dangerous levels of arsenic were also found, and remediated, in the soil at the American University Child Development Center.

The work in Spring Valley is still ongoing, even with the most complex part of the cleanup completed. Of 92 private properties the Army Corps identified with possible buried ordnance in their yards, 85 have been remediated. Work on four more properties begins this month. Mitchell says the remaining remediation will likely be completed in 2 to 3 years.

This story is from DCist.com, the local news website of WAMU.