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Geosptec consultants Elimination System (NPDES) permit/Waste Discharge Requirement (WDR) Order No. R5-2005-0144-01, issued by the CVRWQCB on July 29, 2010. The Phase III IRA includes the addition of six (6) B-Zone extraction wells along the eastern boundary of Lincoln Center, adjacent Pacific Avenue, and four (4) B-Zone and six (6) A-Zone extraction wells downgradient from Lincoln Center, along Inglewood Avenue. Wells are spaced at approximately 150 to 200 foot intervals. Installation and construction of the Phase III IRA was completed in June 2002 and groundwater extracted from these wells is transported via additional conveyance lines to the existing extraction system(Phase I GWETS) (LFR, 2002). The treatment system within the existing GWETS installed for the Phase I IRA was sized to handle a flow rate of approximately 300 gallons per minute (gpm). Currently, the expanded system is extracting at a rate of approximately 140 to 180 gpm and the influent PCE concentration is 0.2 and 0.3 parts per million (ppm). The GWETS is monitored regularly as part of the NPDES permit requirements and a total of approximately 4,728 pounds of PCE has been removed from the combined A- and B-Zone groundwater extraction systems (Phase I and III IRAs) as of July 2010 (ARCADIS,2010). Though considerable mass has been removed by the GWETS, it is not clear from the site data that the GWETS has been fully effective in stopping the migration of contaminants, due in part to the complexity of the subsurface hydrogeology. In early 2012, a booster pump was installed in the conveyance line along Pacific Avenue to allow for increasing individual extraction well rates. In addition, a two- dimensional analytical flow model was developed to simulate capture zones under varying pumping scenarios. Using the flow model and the added capacity from the booster pump, the extraction rates from the individual wells were adjusted to optimize the GWETS. Based on the flow model it appears as though, with the addition of the booster pump and subsequent extraction rate adjustment, that the GWETS is achieving hydraulic capture of the VOC plume in both the A- and B-Zones. 2.21.2 Phase VIRA The Phase V IRA was implemented from early November 2007 to mid-February 2008 and includes a network of 22 injection wells screened in the A-Zone to cut off the groundwater plume at Pacific Avenue. Each well was injected with approximately 15,000 gallons of edible oil substrate (EOS) diluted with water to an approximately 10 percent EOS solution to create an enhanced reductive dechlorination (ERD) barrier to accelerate the remediation of the A-Zone aquifer immediately east of Pacific Avenue Pr Design Investigation Work Plan 8 18.05.12