The U.S. Army Corps of Engineers began excavating arsenic-containing soil from the southeast corner of the Kreeger building, as well as adjacent properties on Rockwood Parkway on Aug. 29, after soil sample tests showed arsenic contamination above acceptable levels.
Samples of soil from grids measuring 20 feet by 20 feet located behind Kreeger were screened for arsenic and came back above 20 parts per million, said Gary Schilling, Spring Valley project manager for the Baltimore District of the Army Corps of Engineers. Arsenic levels below 20 parts per million can be left in the ground, he said, because there is less concern for long-term effects.
A number of exposure studies have been conducted on local residents and AU maintenance workers, and no one has shown increased arsenic levels, Schilling said. It's a level the EPA and the D.C. Department of Health consider "clean," he said.
"A lot of these elements ... exist naturally in soil," Schilling said.
The Corps of Engineers will remove 535 cubic yards of soil - about 15 or 16 grids, Schilling said. The deepest they will have to dig is about three feet.
The operation will only last until mid-September, Schilling said, but the Corps of Engineers will continue to work in the area through 2010.
The Corps of Engineers is now investigating debris near the Public Safety building, Schilling said. Seven areas surround the Lot 18 debris field and contain similar debris, and Public Safety is located in one of these, he said.
The Spring Valley excavation site was known as the AU Experiment Station during World War I, as The Eagle previously reported. Chemical weapons, such as mustard gas, were researched and tested at the site. At the time, the Spring Valley area included several family-owned farms and AU's campus.
The Corps of Engineers is investigating how far the area extends around the building and the "nature and extent" of the debris, Schilling said. They plan to start removing debris this fall or winter.
Former university president Ben Ladner's old residence, 4835 Glenbrook Road, will also be investigated for ordinance-related items and any residual risks from the World War I era, Schilling said. The Corps of Engineers plans to start its investigation next fiscal year, he said.
