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Eckert Cold Storage Company 757 Moffat Blvd:, Manteca, California November 26, 1997 • Underground Tank Investigation, Continued Phase I Report of Findings Page: 2 On January 26, 27 & 30, 1995, WHF drilled three soil borings and completed each as a groundwater monitoring well with two-inch i.d. PVC casing. Samples from the borings ' were analyzed to determine the extent of the soil contamination plume. The three monitoring wells provided data for determining gradient and analyses of the underlying groundwater. During the initial development of the wells, it was discovered that the well casing in MW- 2 had been damaged during installation of the well. Bailers and pumps would not go down the well and only water level readings could be taken with an electronic sounder. Rather than overdrilling this well and setting a replacement well, it was decided to keep ' this well for gradient information. Because all three borings had contamination, it was decided to place the replacement well in the down-gradient direction. On March 22, 1995, a replacement well, MW4, was installed (Figure 3). 3.0 Scope of Work ' On September 18 and 19, 1997, WHF, Inc., in conjunction with Frontier Drilling Company, a licensed C57 Contractor, did drill three (3) soil borings and converted same ' to groundwater monitoring wells with 2" I.D. PVC casings. Sample from the borings were analyzed to determine the extent of the soil contamination plume. The three (3) new monitoring wells, MW-5, 6 & 7, were developed in conjunction with HKM ' Environmental, Inc., on November 4 and all 6 monitoring wells were purged and sampled on November 5, 1997. This event provides data for the gradient determination and an analysis of the underlying groundwater. 31 Drilling Permits were obtained for all wells before drilling began. The soil borings were accomplished using a mobile mounted drilling rig employing the use of a hollow stem ' flight augers of 7 and 10-inch o.d. ' All drilling equipment was thoroughly steam leaned 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 E). The color, texture, moisture, plasticity (if applicable), consistency of the earth materials, pertinent soil or bedrock characteristics, and any evidence of contamination were noted. All water- bearing zones and the depths at which they were encountered were noted on these logs (Appendix Q_