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NICKLEINFELDER Following completion of the drilling, a 2-inch diameter PVC well will be installed in each of the borings. The soil borings will be advanced approximately 10 feet into groundwater. The wells will be constructed with Schedule 40 PVC, a 15 foot long 0.010 inch screened section surrounded by and covered by clean sand filter pack (#2/16), 3 foot thick bentonite transition seal above the filter pack, and grouted to the surface. The wells will be finished with a locking pressure cap situated within a monument or flush style well box (depending on surface conditions). See the proposed Diagram of Well Construction(Plate 3). Once the monitoring wells have been installed, the top of each well will be surveyed so that depth to groundwater measurements in the wells can be converted to groundwater elevations used to assess groundwater gradients. The wells will be surveyed relative to a local benchmark. If a local benchmark is not available near the site, the wells will be surveyed relative to an onsite, assumed benchmark with an assigned elevation. The wells will be surveyed as described in Appendix A-3.4. 3.1.3 Monitoring Well Development A minimum of 48 hours after installation, the monitoring wells will be developed to remove fine silt from the well bore and to effectively increase the hydraulic radius of each monitoring well. Surging along the screened interval of the well will be performed to draw the sediment from the formation into the filter pack and the well and to set the sand filter pack. The monitoring wells will be developed as described in Appendix A.3.2. In addition to developing the monitoring wells until the discharge runs relatively clear of fines, the discharge will be periodically monitored for turbidity, pH, temperature, and specific conductance to record stable groundwater parameters during the development task. The well development purge water will be contained in 55-gallon drums pending analytical results. 3.1.4 Initial Groundwater Sampling Water level measurements will be made in the monitoring wells prior to purging and sampling the wells. The depth to groundwater will then be measured in each well according to the protocol described in Appendix A-4.1. Approximately three to five well volumes will be purged and samples will be collected as described in Appendix A-4.2. Each of the water samples collected for quantitative analyses will be submitted under chain-of-custody control to a laboratory certified by the State of California Department of Health Services (DHS) for the requested analyses. 3.2 SHALLOW SOIL SAMPLING There were numerous areas of concern identified in the ESA that required shallow soil sampling. Kleinfelder proposes to collect shallow soil samples from the orchard area and vehicle parking areas, ground surface depression near the eastern edge of the site where stormwater runoff 27125.E01/ST03R657 Page 6 of 15 Copyright 2003,Kleinfelder,Inc. May 23,2003