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12 June 2012 AGE-NC Project No. 99-0682 Page 6 of 7 a result of historical deeper ground water conditions and/or a steep downward vertical gradient between wells MW-1A and MW-8 (approximately 0.01 ft/ft). • Bromate was detected in samples collected from wells MW-1 A, MW-6, and MW-8 at concentrations ranging between 1.55 mg/I (MW-1A) and 2.86 mg/I (MW-6). Bromate concentrations were significantly above the State of California Primary MCL of 0.01 mg/I for drinking water. • Various dissolved metals (Ba,Al, Ca, Fe, Mg, Mn, and Na)were detected in ground water samples collected from wells MW-1A, MW-6, MW-7, and MW-8 at low concentrations. With the exception of Al from well MW-1A, metal concentrations were all below their respective State of California Primary MCLs for drinking water. However, concentrations of Fe and Mn detected in wells MW-1A, MW-6, and MW-7 were above their respective State of California secondary MCLs for drinking water. • Hexavalent chromium was not detected above the laboratory reporting limit (0.2 pg/1) in ground water samples collected from wells MW-1 A, MW-6, MW-7, and MW-8. Nitrate as N and Nitrite as N were detected in ground water samples collected from wells MW-1A, MW-6, MW-7, and MW-8 above their respective Primary MCLs (Nitrate as N, 10 mg/I and Nitrite as N; Nitrate as NO3 was detected in samples collected from wells MW-1A, MW-6, MW-7, and MW-8 at concentrations below its Primary MCL (Table 4). • Dissolved oxygen (DO), pH, electrical conductivity, total dissolved solids (TDS), chloride, sulfate, redox potential (ORP), and salinity were all detected at low to normal background concentrations. • Ammonia was detected in samples collected from wells MW-1A, MW-6, MW-7, and MW-8 at a maximum concentration of 4.98 mg/I in MW-8. 5.0. RECOMMENDATIONS Based on the conclusions presented in this report,AGE recommends continuation of semi- annual ground water monitoring. Further, AGE recommends performance of an in-situ chemical oxidation pilot test as outlined in the AGE-prepared, Ground Water Remediation Feasibility Study Work Plan, dated 31 October 2011. AGE has scheduled the performance of the pilot test for June 2012. Advanced GeoEnvironmental,Inc.