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Eckert Cold Storage Company 757 Moffat Boulevard January 3, 2000 . Manteca, California Page: 3 ' 3.1 Drilling Permits were obtained for the borings and monitoring well before drilling began. The soil ' borings were accomplished using a mobile mounted drilling rig employing the use of a hollow stem flight auger no less than 3 1/4-inch i.d. and 8-inch o.d. ' All drilling equipment was thoroughly cleaned before drilling began, to prevent the introduction of contamination from off site, and between borings to prevent cross contamination. The borings were logged under the direct supervision of a registered professional using ' the Unified Soil Classification System (Appendix A). The color, texture, moisture, plasticity (if applicable), consistency of the earth materials, pertinent soil or bedrock characteristics, and any evidence of contamination was noted. All water-bearing zones ' and the depths at which they were encountered was noted on these logs (Appendix B). All borings were drilled in such a manner as to prevent cross contamination between ' strata. Exploratory soil borings within the unsaturated zone were backfilled with a cement and three percent (3%)Bentonite mixture. e The cuttings from the drilling operation were containerized on-site during drilling for proper disposition. 3.2 Well Construction ' All materials used in well construction were thoroughly cleaned prior to introduction into the boring. A Bentonite or cement and Bentonite grout was placed at the bottom of the ' boring as necessary. After the seal has been allowed to set long enough to support the weight of the casing, a two inch (2") diameter well casing (stainless steal or PVC) with end cap and factory perforations for placement in the saturated zone (taking into account seasonal variation) was placed in the boring. The screen and filter pack sizes is as noted in the well construction drawing. The filter pack extended two feet (2') above the perforated zone. A Bentonite seal two to three feet (2-3') thick was placed in the annular space above the filter pack followed by a cement grout to the surface(Appendix Q. 3.3 Soil Sampling All soil sampling equipment was thoroughly cleaned before and between sampling to ' prevent cross contamination. Relatively undisturbed soil samples were taken at intervals of not more than five feet (T) in order to evaluate the subsurface materials.