FINAL SITE INSPECTION REPORT

96796896997097197297397497597697797897998098198298398498598698798898999099199299399499599699799899910001001Mk 6 2.25-inch practice rockets were constructed from sheet metal. The propellant used in therocket was ballistite, which consists of nitrocellulose and nitroglycerin. There were no spottingcharges in the Mk 6 rockets. The use of the Mk 6 practice rocket is thought to be limited at thistarget as evidenced by the scarcity of spent rocket motors. The reported AN-M57 GP practicebombs contained a spotting charge only. The AN-47 practice bombs were reported in the PA/SI(Weston, 2004) and may have been sand filled or were smoke or incendiary munitions. All ofthe above munitions contained relatively insensitive explosive components, except the AN-M47which may have contained a sensitive fuze.5.3.1 Field Observations and Historical Evidence of MECThe types of munitions used at the Target No. 2 AOC are listed above. Debris from thesemunitions was observed during the ASR site visit in 1997, during the 2004 PA/SI investigation,and in 2006 during a Navy EOD recovery. The ASR indicated that four 75-mm HEAT M66projectiles were reported to have been destroyed in the target area by Army EOD in 1987. TheASR indicated that the 75-mm projectiles were likely brought to the AOC for disposal and notused at the site. MEC was reported from this AOC as recently as March 2006.No field reconnaissance was conducted at this AOC during the SI because MEC and MD werereported as recently as March 2006. However, prior to collecting soil samples, the path from thevehicle to the sampling point was visually surveyed and the path recorded using a GPS unit by aUXO technician with the aid of an all-metal detector. No MEC or MD was noted duringsampling activities. The path is shown on Figure 5-1.5.3.2 MEC Risk AssessmentThe following section presents a qualitative assessment of the risk associated with potentialMEC, as based on historical documentation, prior investigation, and visual inspection conductedduring this SI. A MEC assessment is provided to convey relative risk on a scale from low tohigh and is not intended to be a thorough risk assessment as would be conducted for an RI/FS.Access to Target No. 2 is unrestricted. The area is used for irrigated agriculture and physicalbarriers are not present.MEC has been reported historically at Target No. 2 as recently as March 2006. The MEC riskfor this area is considered to be moderate based on the following: MEC has been reported as recently as March 2006, recent finds were AN-M57 GPpractice bombs; All munitions contained relatively insensitive explosive components except for theAN-M47, which may have had a sensitive fuze; The area is used for farming, undergoing yearly tillage to depths of approximately 18inches and MEC and MD is periodically unearthed;Boardman AFR Final SI Report.doc 5-2 Contract No. W912DY-04-D-0010 Delivery Order No. 003September 2007