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kn KLEINFELDER of the facility. Directly north and northeast of the CNP site on the north side of Lathrop Road the Sharpe Army Depot is located. Along the southern portion of the Sharpe Army Depot is at least ten (10) groundwater extraction wells (EWAl through EWA10) and at least twenty-four (24) monitoring wells within approximately 2,400 feet of the CNP site. Groundwater level contour maps prepared for the Sharpe Army Depot site show groundwater flowing predominantly to the north or northeast in the area of extraction well EWA5 (located within approximately 1,600 feet from CNP) with the exception of the fourth quarter 2001 data which shows groundwater flow in that area to the west. It should be noted that it appears that many of the extraction wells including EWA6 and EWA8 were not operating during this period of data collection. Additionally, two smaller capture zones are noted at locations EWA6 and EWA7 with flows to the north/northwest. On the southeastern portion of the Sharpe Army Depot (furthest away from the CNP site) there appears to be two distinct capture zones with EWA9 and EWA10. Circular depressions are created by the extraction wells and the general flow direction is disrupted showing flow in the area as being from the south, east, and west towards the center. The groundwater elevations noted in the Sharpe Army Depot monitoring well MW440A (located on the Sharpe site's southwest comer and closest to the CNP piezometers) shows approximate correlation to the plant wells groundwater elevations from quarter to quarter over the past four quarters as shown on Kleinfelder's last groundwater monitoring report submitted for March 2002 Table 2, Groundwater Elevation and Flow Data. The elevation benchmark survey data for the Sharpe Army Depot wells is not known at this time for exact correlation. Please refer to the attached groundwater contour maps for the last four quarters of data collection at the CNP site. Groundwater flow in the McKinley Avenue recharge area has been predominantly to the northeast and southeast with a groundwater mound extending east-west between MW-1 and MW-4. The cause of the mound is unknown at this time considering the main application areas are to the north and south of the mounded area. The groundwater contours support Kleinfelder's initial and continued evaluation of the area. Flow in the proposed Louise Avenue application area the groundwater flow direction has been recorded consistently to the west. The Louise Avenue area is located the furthest from the Sharpe Army Depot, approximately 1 mile away to the south and does not have process water applied to the area yet. It does not appear that the Louise Avenue area is affected by the groundwater extraction activities at the Sharpe Army Depot. Item No. 2 Based on the new information transmitted in this correspondence, please reevaluate the well locations proposed on Plate 2 of the well installation workplan. It is difficult to estimate groundwater flow in the area of the site because the site lies just beyond the most western reaching groundwater elevation contour prepared by the San Joaquin County Flood Control District map. Regionally, the map shows groundwater generally flowing to the west/northwest near the area of the site. But the effects of the shallow zone extraction wells C20-4587-0I.MN I /ST021,200 Page 2 of 4 Copyright 2002,Kleinfelder,Inc. September 20,2002