The Army Corps of Engineers suspended its Pit 3 operations at 4825 Glenbrook Rd. indefinitely late last month after workers uncovered an underground cache of laboratory glassware, said Dan Noble, the Corps’ Spring Valley project manager.
The announcement was made during the monthly meeting of the Restoration Advisory Board Tuesday night.
This is not the first time the Corps has paused operations at the Pit 3 investigation. In August 2009, workers unearthed a flask of mustard agent, The Eagle previously reported.
On March 29, workers conducting a high-probability investigation — meaning extra safety precautions are used — discovered the remains of a rusty metal drum containing several glass bottles buried seven feet under the ground.
One intact bottle is confirmed to contain mustard agent, while another contains a liquid that is still under analysis.
In addition to laboratory glassware and contaminated soil, workers recovered a World War I-related munition containing tear gas.
After noticing that the soil around the drum was smoking and one of the bottles was emitting a white vapor, workers sealed off the area and covered the area in plastic, Noble said.
Workers immediately sent a sample to the Corps’ chemical center in Edgewood, Md., for analysis.
Initial tests confirmed it had traces of mustard. Tests also showed traces of arsenic trichloride, an “acutely hazardous” chemical not previously found in Spring Valley, according to Noble.
Arsenic trichloride reacts with moisture in the air to create hydrogen chloride, another highly toxic gas, explaining the white vapor that workers saw, Noble said.
Workers cannot be exposed to levels of the gas above 0.01 milligrams per cubic meter without experiencing adverse health effects, according to Emily Russell, a technical consultant for the Department of Defense.
It is currently unclear whether the arsenic trichloride in the air around the dig site exceeded these levels, as the Corps is still waiting on test results.
Both chemicals are on the list of compounds developed at the AU Experimental Station.
The Army used arsenic trichloride to make lewisite, another compound used in chemical warfare, according to Noble. Army scientists during World War I were also interested in mixing arsenic trichloride with mustard, and AUES reports indicate that scientists were developing a compound consisting of half mustard, half arsenic trichloride, Noble said.
“They were trying to make mustard [gas] worse,” Noble said.
Four barbecues for graduating seniors are scheduled to take place next week at the AU president’s house, located next door to the 4825 Glenbrook Rd. property.
When asked if AU students have anything to worry about, Noble said the situation is under control.
“They basically took the one item that was smoking ... [and] they put it into plastic bags to contain it and then they immediately covered the excavation with plastic,” he said.
David Taylor, chief of staff to President Neil Kerwin, said the Corps has been provided with a list of planned activities.
“They are aware of the heavier-than-normal schedule, and would let us know of anything new or unusual,” he said in an e-mail.
The Corps continues to find glass bottlenecks at the property. Workers have unearthed 10 bottlenecks since resuming work in January, according to Noble.
4825 Glenbrook Rd. is thought to be the site of a long sought-after munitions cache, known as the “Sgt. Maurer burial pit,” The Eagle reported in February.
To date, the Corp has removed 500 pounds of laboratory glassware, 60 pounds of scrap metal and 238 barrels of contaminated soil from Pit 3.
Noble also reminded RAB members that once the Corps is finished with its high-probability work, it still has some low-probability work to finish at Pit 3, namely the completion of seven more test pits, a small amount of arsenic removal in the driveway, additional soil sampling in the backyard and geotechnical borings in the basement of the house.
You can reach these writers at news@theeagleonline.com.
