SITE INFORMATION AND CORRESPONDENCE

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Nftwl -2- The following site investigation is based on minimum requirements de- termined during conversations with local county health officials. Site Investigation In order to determine if ground water has been impacted significantly from the product lost during the tank removal, a preliminary Phase I evalu- ation will be conducted. The information gathered during the Phase I inves- tigation can be used, if necessary, to develop a more in-depth plan. Phase I Subsurface Investigation, if approved, will consist of the following: 1. Installation of 3 monitoring wells as indicated on the enclosed plot plan. The monitoring wells will be placed in a triangle at least 100 feet apart in order to determine ground water gradient. 2. A description of subsurface conditions at the site as revealed in the 3 borings prior to well installation. All borings shall be des- cribed in detail using the Unified Soil Classification System. A technician trained and experienced in the use of the Unified Soil Classification System working under the direct supervision of a California State Certified Engineering Geologist will log the borings. Geologist William R. Henkle, E.G. 001233, will review the work and assume responsibility for the accuracy and completeness of the logs. 3. Collection of relatively undisturbed soil samples taken at 5 feet be- neath trP surface, and at 5 foot interval��t"�ie er after, witfiiYi ri (saturated zones ana ysis. e analyses will concis o o rocar �� 4. Prior to development of the 3 wells, water will be removed using a clean teflon bailer and checked for floating product. Once the wells have been developed, a minimum of five volumes of water will be re- moved and the water sampled and analyzed for Total Petroleum Hdyro- carbons including BTX. All analyses will be performed by California Water Labs, a State and EPA;certified laboratory. Soil Borings and Monitoring Wells Soil borings will be conducted using a truck mounted drill rig equipped with an 8 inch hollow stem auger. Samples will be taken with a California Modified Split Spoon containing cleaned brass sleeves. All auger sections and sampling equipment will be steam cleaned prior to use and between samples and bore holes to minimize the possibility of cross-contamination. Bore holes will be logged as drilled and soil samples will be classified in accordance with the Unified Soil Classification System. All soil samples collected for possible analysis will be capped with aluminum foil lined lids, sealed with tape, and immediately placed in iced storage for transport to the laboratory.