SITE INFORMATION AND CORRESPONDENCE

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Mr. Harlin Knoll Project No. 2007-065-01 May 19, 2000 Page 2 Additional monitoring wells (MW-4, MW-5, MW-6 and MW-7) were installed to assess the lateral extent of petroleum hydrocarbon impact to groundwater to the south. Figure 2 presents the location of all monitoring wells. Pinnacle Environmental Solutions, a division of EMCON prepared and submitted a Remedial Action Plan (RAP) in January 1999. The RAP recommended the construction, installation and operation of a soil vapor extraction and air sparge system to mitigate the petroleum hydrocarbon impact to soil and groundwater. SITE ACTIVITIES Site activities conducted on May 4, and 5, 2000 are summarized below. • Advanced two soil borings and convert them to groundwater monitoring wells, • Installed one air sparge well, • Destroyed one monitoring well, • Collected soil samples for chemical analysis, and • Developed and sampled two groundwater monitoring wells. Stratus obtained an encroachment permit from the City of Lodi to destroy monitoring well MW-5 located in the shoulder of the Lower Sacramento Road(see Appendix A). Exploratory Borings and Sampling On May 4 and 5, 2000, a Stratus geologist supervised Western Strata Exploration, a California licensed drilling contractor, advance three 8-inch diameter exploratory soil borings at locations shown on Figure 2. All the borings were drilled to a total depth of 51 bgs. The work was performed under the direction of a California registered geologist. Stratus field procedures are presented in Appendix B. Undisturbed soil samples were collected for classification and laboratory analyses at approximately 5-foot intervals or at soil lithology changes. Soil samples were obtained from the borings using a modified California split-spoon sampler. The soil samples were classified using visual and manual methods according to the Unified Soil Classification System. The borings were logged by a Stratus staff geologist. The logs of the exploratory borings are presented in Appendix C. Drilling and sampling equipment was steam cleaned after each boring was completed to reduce the potential for cross- contamination. One soil sample from each boring was collected for analysis from at or just above first encountered groundwater, at an approximate depth of 40.5 feet bgs. Select soil samples from each boring, exhibiting petroleum hydrocarbons impact, as detected by a flame CAMy Documents\USA165Veport.doe Stratus