FINAL SITE INSPECTION REPORT

1743174417451746174717481749175017511752175317541755175617571758175917601761176217631764176517661767176817691770177117721773177417751776indicates that the perchlorate detected in groundwater samples is not originating from sourceswithin this AOC or the Boardman AFR FUDS.10.5 Demolition Area No. 2MEC has been identified within the Demolition Area No. 2 vicinity as recently as June 2006. Avisual reconnaissance of the area was completed during the SI field activities and large quantitiesof MD were observed in the area of the disposal pits. Based on the reported presence of MECand MD, the risk for potential MEC is considered moderate based on the following: Recent find and demolition of a M83 butterfly bomb by Oregon State Police EOD Unit; Observed accumulations of MD; Sensitive fuzes contain in reported MEC and MD; Access through locked gates but unpatrolled.Two soil samples were collected from Demolition Area No. 2 and analyzed for select metals andexplosives. All metals detections were below Boardman AFR background concentrations.There were no explosive detections.No groundwater samples were collected from Demolition Area No. 2. However the PA/SIcollected groundwater sample from wells located cross and down gradient of the FUDS (Weston,2004). Samples were analyzed for explosives and perchlorate. There were no explosivedetections. Perchlorate was detected in 18 of 25 wells sampled. All results were below the DoDaction level. The ODEQ has identified perchlorate in groundwater throughout the lowerUmatilla Basin in wells located within 10 miles from the Boardman AFR (ODEQ, 2005). Basedon studies completed by the ODEQ and EPA (ODEQ, 2005), perchlorate is found throughout thelower Umatilla Basin in wells located up, cross, and downgradient of the Boardman AFR. Thisindicates that the perchlorate detected in groundwater samples is not originating from sourceswithin this AOC or the Boardman AFR FUDS.10.6 Impact AreaMD has been reported by workers in the vicinity of the Impact Area. No MEC has beenreported. No MEC or MD was identified during the SI field visual reconnaissance. The risk forpotential MEC at the Impact Area is considered to be low based on the following: No MEC has been reported at this AOC; No observed accumulations of MD during the SI. However, an employee of The NatureConservancy stated that he has observed MD at the AOC; Munitions assumed to have been used at the Impact Area contain no sensitive explosivecomponents; Access to area is only through locked gates.Boardman AFR Final SI Report.doc 10-5 Contract No. W912DY-04-D-0010 Delivery Order No. 003September 2007