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McCormick and Baxter 2 12 July 1990 - Ambient water quality criteria for protection of aquatic life. - Reference concentration for noncarcinogens. - 10 excess lifetime cancer risk. 3) The Phase I remedial action goals for the portion of the plume hydraulically controlled by Newark-Sierra's (formerly Gold Bond's) production wells were based upon a dilution factor of 60. 4) The largest target area requiring remediation was the target area associated with PCP. 5) Based upon an analytical model , six onsite wells (including four existing wells) , and five offsite wells (6 inch in diameter) were determined to be capable of meeting remedial objectives for the four shallow aquifer zones (A through D) . The total flow rate is estimated at 500 gpm. 6) An initial extraction system consisting of four existing onsite wells, two new onsite source wells (one within the A zone and one within the D zone) , and two near offsite wells (near Cedar Wood Products and completed in Zones A to D) will be constructed. The initial flow rate is estimated at 269 gpm, which is the available capacity of the existing 12 inch diameter Garfield Street trunk line. Apparently, this was the reason for installing initially only a portion of the extraction system. In addition, at least eighteen piezometers will be installed to verify that the installed extraction system's capture zones are sufficient to meet remedial objectives (however, Figure 7-7 indicates that 26 piezometers will be installed) . Fifteen new monitoring wells will be installed to verify that the target areas within each aquifer zone are adequately delineated. 7) The initial extraction system will be operated and monitored on a monthly basis for six months to determine the actual capture zones within each aquifer zone, and to evaluate the changes in contaminant concentrations with time. Depending upon the water quality and hydrogeologic data collected during the first six months, additional extraction wells (and necessary piezometers and/or monitoring wells) may be installed. At least three additional offsite extraction wells will be required based upon the consultant's original modeling effort (Item 5 above) . The need for an additional trunk line to the SRWCF will then be determined. 8) Once Item 7 is completed a Performance Monitoring Program will be implemented. This program consist of an annual sampling of 21 monitoring wells, 11 extraction wells, and the two Gold Bond wells, quarterly sampling of the discharge to SRWCF, and quarterly water level measurements of extraction wells, monitoring wells, and piezometers (monthly for the first year) .