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— 4 KLEINFELDER The soil borings will be drilled with a truck mounted drill rig equipped with 8-inch hollow stem augers to a total depth of approximately 70-feet to 90-feet below the ground surface (bgs), depending upon where first the regional aquifer is encountered. During advancement of the soil borings, soil samples will be collected every 5-feet in the each soil boring for lithologic classification. Lithologic classification will be based on the Unified Soil Classification System (USCS). The soil borings will be advanced approximately 10 feet into groundwater. All equipment used in the drilling and installation procedures will be cleaned and/or decontaminated. Based upon available information, we anticipate groundwater in the vicinity of the project site to be present at a depth of approximately 60-feet to 80-feet bgs, with a groundwater flow direction to the north. Following completion of the drilling, a 2-inch diameter PVC well will be install in each of �I1`b6 the borings. The wells will be constructed with Schedule 40 PVC, a 2 bot long 0.020 `j'J* inch slotted screened section (15 feet below water and 10 feet &I ove water where applicable) 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 style well vault. Once the wells have been installed, the top of each well will be surveyed by Stantec Consulting, Inc. 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. Monitorinq 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 monitoring well will be performed to draw the sediment from the formation into the filter pack and the monitoring well and to set the sand filter pack. In addition to developing the 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 development purge water will not be contained and discharged to the ground surface. Initial Groundwater Sampling It is anticipated that original groundwater quality data will be required to characterize the site. Therefore, we propose to collect groundwater samples from each of the newly installed groundwater monitoring wells for laboratory analyses to represent a baseline 02001 PROP.ENV/ST05P346R/JDZ:ly Page 3 of 12 ©2005 Kleinfelder, Inc. December 2, 2005