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All dissolved metal concentrations in groundwater were either below laboratory reporting limits ' or were below respective Maximum Contaminant Levels (MCLs). A statistical analysis was conducted by Geocon to evaluate the correlation between 1)XRF readings and laboratory analytical results for total lead, 2) total and WET lead concentrations, ' and 3)total and TCLP lead concentrations (Geocon 2015). The following findings were reported: 1. A correlation exists between XRF and total lead results up to 2,000 mg/kg and XRF readings above 2,000 mg/kg tended to underestimate total lead concentrations. ' 2. Lead in surface soil is highly soluble (by the WET and TCLP methods) and total lead concentrations greater than 50 mg/kg are expected to exceed the STLC of 5 mg/l and total lead concentrations greater than 135 mg/kg are expected to exceed the TCLP of 5 mg/l. The following volumes of soil exceeding California and RCRA hazardous waste criteria were ' estimated by Geocon (Geocon 2015): 1. 490 yds3 (780 tons) of California hazardous waste ' 2. 660 yds3 (1,050)tons of RCRA hazardous waste These estimates are based on removal of soil from the firing range floor and impact berm with ' lead concentrations exceeding the Residential California Human Health Screening Level (CHHSL) for lead of 80 mg/kg. SKEW Summary ' The goal of the removal actions presented in this SREW is, when fully implemented,to place the Site in a condition that allows it to be permanently used for its planned use without any ' significant risk to human health or any significant potential for future environmental damage. The removal actions proposed for the Site which meet this requirement include excavation and offsite disposal of soil with COPC concentrations exceeding proposed cleanup goals. 1 PACIFIC EDGE ENGINEERING iv SREW_Manteca_draft.docx ' (949)470-1937;(949)470-0943(FAx)