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24 July 2012 <br /> AGE-NC Project No. 10-1801 <br /> Page 2 of 5 <br /> 2.0. SITE BACKGROUND <br /> A total of forty-two ground water monitoring and remediation wells (MW-1 through <br /> MW-13B, MW-19AB, MW-20AB and EW-1 through EW-10) have been installed on-site <br /> and off-site; as-built well construction details for all Flag City Shell wells are included in <br /> Table 1. The following is a brief summary of milestones regarding the Flag City Shell <br /> investigation: <br /> • Between August 2005 and September 2007, ground water monitoring wells MW-1 <br /> through MW-13 were installed on-site and off-site as part of an ongoing leaking <br /> underground storage tank(UST)subsurface investigation. During the investigation, <br /> MTBE-impacted ground waterwas identified as the primary constituent of concern. <br /> • Between September2006 and September 2008,ground waterextraction wells EW-1 <br /> through EW-10 were installed on-and off-site for operation of a ground water pump- <br /> and-treat remediation system; ground water remediation was performed at the site <br /> by extracting MTBE-impacted ground water from wells EW-1 through EW-10. <br /> During the above-referenced ground water remediation operational period, a total <br /> of 23,517,871 gallons of MTBE-impacted waterwas treated and discharged off-site <br /> under CRWQCB-CVR General Order No. R5-2008-0085-013, National Pollutant <br /> Discharge Elimination System (NPDES) Waste Water Discharge Permit No. <br /> CAG915001. <br /> • On 10 August 2011,all ground water remediation operations were suspended at the <br /> site, due to declining MTBE concentrations. In a letter dated 10 August 2011, the <br /> RWQCB-CVR directed the submittal of a closure report. <br /> • On 10 October 2011, a Closure Summary Report was prepared by AGE and <br /> submitted to the R\AfQCB-CVR. AGE recommended that the site be considered for <br /> closure as a low risk ground water site. <br /> • On 31 January 2012, the RWQCB-CVR indicated that the site was being <br /> considered for closure as a low risk ground water site and directed that all wells <br /> associated with the Flag City Shell investigation needed to be properly <br /> decommissioned. <br /> 3.0. PROCEDURES <br /> In accordance with the above-referenced 31 January 2012 CRWQCB-CVR directive,AGE <br /> is proposing to decommission a total of forty two (42) wells, including the destruction of <br /> monitoring wells MW-1 through MW-13B, MW-19AB, MW-20AB and extraction wells EW-1 <br /> through EW-10 (Table 1). <br /> Advanced GeoEnviron mental,Inc. <br />