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kn KLEINEELDER Following completion of the drilling, a 2-inch diameter PVC well will be installed in 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 0.020 inch screened section surrounded by and covered by a sand filter pack (#2/12), 3 foot thick bentonite transition seal above the filter pack, and grouted to the surface with a neat cement mixed with no more than 3% to 5% bentonite powder to retard the heat of hydration and limit the possibility of damaging the PVC casing.. The wells will be finished with a locking pressure cap situated within a monument or flush style well vault (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 (by a licensed surveyor) 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 Section A-3.4. 3.3 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 set the sand pack. The monitoring wells will be developed as described in Appendix A Section 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 pH, temperature, and specific conductance. The well development purge water will be discharged to the land surface and will not be allowed to flow off the site. 3.4 INITIAL GROUNDWATER SAMPLING Groundwater samples will be collected from the 2 new monitoring wells and the wells will be incorporated into the quarterly groundwater monitoring schedule in accordance with the M&RP . It is anticipated that the 2 new monitoring wells will be sampled during the third Quarter 2002 groundwater monitoring event. Water level measurements will be made in the monitoring wells prior to development, purging and sampling the wells. The depth to groundwater will then be measured in each well according to the protocol described in Appendix A Section 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 20-4587-02.WP2/2002R489 Page 6 of 12 Copyright 2002,Kleinfelder,Inc. June 6,2002