Preparations Continue for Erection of "Engineering Control Structure"

The Corps of Engineers will use a large (60 feet by 82.5 feet) Engineering Control Structure (ECS) with a Chemical Agent Filtration System (CAFS) during the high probability work.  The ECS will fully enclose the excavation. The CAFS keeps the ECS under negative pressure by continuously pulling, filtering and cleaning all the air leaving the control structure ... The MCE [maximum credible event] for this activity is the evaporative release of one liter of arsenic trichloride over a one-hour period.

If there were no engineering controls in place, the Temporary Emergency Exposure Limit distance for this MCE would be 194 feet, which impacts eight residents and Watkins Hall on American University (AU).  If warranted, due to the highly improbable failure of the ECS and CAFS at the same time there is a release, the Corps of Engineers will implement another precautionary measure for both the workers and neighbors within 194 feet: a Shelter-in-Place alert and notification system.
The Corps'pondent

Vol. 14, No. 1

April 2013 (pg. 1)

  Spring Valley FUDS Timeline

Start of Glenbrook High Probability Digging Postponed until Summer

 

Work has begun at the university-owned site (4825 Glenbrook Road) for what is hoped will be the final phase of the effort to find and safely remove any remaining World War I debris from that property ... In May, the work will shift into a new phase and a containment structure will be built over the excavation site; air filtration and monitoring equipment installed; and additional safety instruction will be provided for areas of the university within a defined zone adjacent to the site.  This would include the Watkins and Kreeger buildings, the Jacobs athletics field, and the President’s House.  When the specific work timeline is known, those working in the affected areas will be informed of safety measures and protocols, which will be posted on the AU website dedicated to the project.

Neil Kerwin, President 

American University

April 3, 2013

 Crew excavates last test pit at 4825 Glenbrook

This week crews continued the installation process for the trench to support utility relocation at the site. Utility relocation will take approximately two more weeks ... As an added layer of safety, air monitoring was used during all excavations ... During the week of April 8, crews will relocate and re-establish the sewer line.  The water line will be relocated and re-established the week of April 15.  

We anticipate starting the high probability excavation work this summer ... Recently we have had weather delays and issues related to the relocation of the site utilities ... Due to the deeper location of the utilities more expansive trenches are required, which increases the complexity of the work ... Crews will work some limited Fridays and Saturdays from now until June to make up for the schedule delays to minimize an impact to the completion of the project.

4825 Glenbrook Road
Weekly Update
April 5, 2013