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30 January 2014 AGE Project No . 99-0682 Page 15 of 28 Based on results of the ISCO pilot test AGE concluded the following : • Based on progress and post-ISCO sampling , dissolved metals generally decreased or remained stable in well MW-1A; marginally increased in well MW-6; increased in well MW-8 ; and generally remained stable or fluctuated in wells MW-7 and MW-10 (Table 4). Specifically, Fe and AI concentrations increased in well MW-8 significantly compared to baseline concentrations , but have been steadily declining after termination of the pilot test. Additionally, Cr was detected in the samples collected from MW-8 during the 28 June and 12 July 2012 post-ISCO sampling events ; Cr decreased to non detect levels during the final post-ISCO sampling event on 12 July 2012 . Concentration of Cr detected were below the State Primary MCL of 0 . 05 mg/I . • Based on progress and post-ISCO sampling , anions bromide and bromate fluctuated throughout the pilot test in wells MWAA, MW-6 , MW-7 and MW-8 . By the end of the pilot test, bromate and bromide were detected at concentrations consistent with baseline levels in injection wells MW-1A and MW-8 , and had increased slightly in samples from observations wells MW-6 and MW-7, with the exception of bromate in well MW-6 which decreased to below baseline levels . (Table 5) . • CrVI was not detected in any samples collected during the pilot test. Based on these results , and general fluctuations of bromide and bromate , it appears that water quality was not adversely effected by the ISCO injections performed at the site . • TPH-g concentrations in injection well MWAA decreased 72 % in comparison to baseline sampling concentrations and benzene concentrations decreased 90% in comparison to baseline sampling results collected in April 2012; additionally, the remaining BTEX compounds decreased significantly compared to baseline and historical sampling results . Graphs depicting concentration trends versus time during the pilot test are presented in Appendix E . • TPH-g concentrations slightly decreased in well MW-7 (24% ), while benzene concentrations decreased 70 % ; the remaining BTEX compounds decreased moderately compared to baseline and historical sampling results (Appendix E). • Following the first two weeks of injections , TPH-g and benzene concentrations significantly decreased in well MW-8 (Appendix E ; Table 3). Following the fourth week of injections TPH-g and benzene constituents were not reported in well MW-8 . However, TPH-g and benzene concentrations both rebounded and increased during each subsequent post-ISCO sampling event. The rebounding of hydrocarbon concentrations can likely be attributed to highly impacted and drowned adsorbed soil impact at the well screen depth . • TPH-g and BTEX decreased approximately 68% and 63% , respectively in well MW-10 as compared to baseline analytical data collected in April 2012 . Based on Advanced GeoEnvironmental, Inc.