FINAL SITE INSPECTION REPORT

115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188explosive documented as being used was black powder. Perchlorate was not identified as apotential MC at Carty Reservoir Bomb Target. Nonetheless, discussion of perchlorate analyticalresults from a surface water sample collected from Carty Reservoir Bomb Target during thePA/SI is included in the following evaluation for completeness.6.4.1 Terrestrial PathwayTerrestrial receptors may be exposed to MC because soil may have been directly affected by thecorrosion of metals from the bomb bodies or explosives used. Two surface soil samples (NWO-030-0004 and NWO-030-0005) were proposed and collected at Carty Reservoir Bomb Target.The samples were analyzed for select metals (chromium, copper, iron, lead, molybdenum, andnickel) by EPA Method 6020A. Chromium, copper, molybdenum, and nickel were included inthe analytical suite for this AOC to be consistent with other AOCs at Boardman AFR. Inaddition, samples were analyzed for aluminum and manganese for potential use in evaluatingnaturally occurring concentrations of metals in soil using the method of Myers and Thorbjornsen(2004). One sample NWO-030-0005 was also analyzed for explosives including nitroglycerinby EPA Method 8330A. The explosives were added at the request of the ODEQ to confirm thanno explosives were present. The sample locations and results are shown in Figures 4-2 and 4-3.No soil samples were collected from this AOC during the PA/SI.6.4.1.1 Comparison to Background DataThe detected metals concentrations in soil are listed on Table 6-1. There were no exceedances ofthe SI background soil concentrations in any sample. There were no explosives detected in theone sample analyzed for explosives.6.4.1.2 Comparison to Human Health Screening ValuesSoil analytical results are only compared to human health screening values if backgroundconcentrations are exceeded. Because there were no exceedances of background concentrations,no comparison has been completed for this SI.6.4.1.3 Comparison to Ecological Screening ValuesSoil analytical results are only compared to ecological screening values if backgroundconcentrations are exceeded. Because there were no exceedances of background concentrations,no comparison has been completed for this SI.6.4.2 Surface Water PathwayPrimary exposure to surface water is through direct contact of PGE workers and wildlife. Onesurface water sample was collected from Carty Reservoir during the PA/SI (SW-CR001) andanalyzed for perchlorate using EPA method CLP-SOW 314.0 (EPA, 2000). One sedimentsample (NWO-030-1001) and field duplicate (NWO-030-1003) were collected from the shore ofCarty Reservoir (Figure 4-2). The samples were analyzed for select metals using EPA SW-846Method 6020A, and explosives including nitroglycerin using EPA SW-846 Method 8330A.Boardman AFR Final SI Report.doc 6-3 Contract No. W912DY-04-D-0010 Delivery Order No. 003September 2007