Colonel Charles J. Fiala, Jr. Response to Questions from Subcommittee on the District of Columbia Committee on Government Reform Spring Valley Formerly Used Defense Site Spring Valley Formerly Used Defense Site 1.) Please describe the boundaries of the work that is being conducted by the Army Corps of Engineers? The investigation currently underway by the Army Corps of Engineers encompasses the entire 661 acres within the boundaries which define the formerly used defense site. The attached map illustrates the boundaries of this site. Spring Valley Formerly Used Defense Site 2.) Are you looking for other contaminants around the Spring Valley site? What are you looking for and what has been found? Are there other areas in the District of Columbia and surrounding region that are being searched for contaminants? Where are the areas and what has been found on those sites? In addition to searching for arsenic, our current sampling includes sampling for other selected contaminants in certain locations. A description of the soil sampling plan is attached, including where we are sampling for contaminants other than arsenic. The Corps' historical research into the Department of Defense's past activities at the former American University Experiment Station identified several other sites where testing may have occurred, including: Catholic University in the District of Columbia, and Fort Foote and the Montgomery County Country Club in Maryland. The Corps plans additional investigation at each of these sites, but to date has not identified any hazards at these locations. SPRING VALLEY OU-5 - Proposed Sampling Plan FINAL SPRING VALLEY OU-5 Soil Sampling Plan Central Test Area (Quadrant Sampling) Page 1 of 5 • Four (4) composite surface soil samples collected from 4 quadrants on every residential lot. The 4 samples consist of soil taken from 6 locations. The 4 composite samples will be analyzed for arsenic. Subsurface samples will be collected from one boring per property. The location of the boring shall be located in an area containing fill. If possible, the location of the boring shall also be located in an area identified as a ground scar/stressed vegetation. The depth of the boring will be based on the cut and fill map developed for the American University Experiment Station (AUES). For properties containing fill material, the boring will be conducted to 2 feet beyond fill (to a maximum of 10 feet). For properties containing only 1918 level or areas of cut, the boring will be conducted to 6 feet below ground surface (bgs). Samples will be collected from each 1-foot level and analyzed for arsenic. • Expanded contaminant sampling based on POI-specific lists of potential contaminants (see below). Samples from the subsurface boring will be used for this testing. Outside the CTA (Halve Sampling Areas) • Two (2) composite surface soil samples on every residential lot. Both samples consist of soil taken from 6 locations. The 2 composite samples will be analyzed for arsenic. Subsurface samples will be collected from roughly 15% of the properties from the area outside of the Central Test Area (CTA). If possible, the location of the boring shall also be located in an area identified as a ground scar/stressed vegetation. The depth of the boring will be based on the cut and fill map developed for the AUES. For properties containing fill material, the boring will be conducted to 2 feet beyond fill (to a maximum of 10 feet). For properties containing only 1918 level or areas of cut, the boring will be conducted to 6 feet below ground surface. Samples will be collected from each 1-foot level and analyzed for arsenic. • Some samples may also be tested for other contaminants (TBD). POI-Specific Sampling Plans ♦POI 19 (CTA) Documentation refers to POI 19 as the "Old Mustard Field" which seems to indicate this area was used to test for agent persistence. Therefore, Mustard and Mustard Agent Breakdown Products (ABPs) are identified as the potential chemicals of concern (PCOCs) and will be analyzed for at this POI. • Surface soil (quadrant sampling) analyzed for arsenic. • Subsurface samples will be collected from one boring per property. The location of the boring http://www.nab.usace.army.mil/projects/WashingtonDC/springvalley/SSP/finalSSP.htm 8/31/01 |