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cgokgical Technics Inc. Page 2 Work Plan Project No. 1128.2 October 22,2003 investigation work. The scope of work was developed in response to infonnation obtained during a phone meeting with Mr. Infurna and his letter of October 17, 2003. 1. One borehole will be drilled under each of the septic tanks. These boreholes will be drilled using GeoProbe methods and will be drilled at an angle so that the sample will be collected under the bottom of the tank. 2. One GeoProbe borehole will be drilled under the distribution box and a sample will be collected within two feet of the bottom of the box. 3. One GeoProbe borehole will be drilled beneath the beginning and at the end of each leach line. These samples will be collected within two feet of the bottom of the line. 4. Nine soil samples will be tested for volatile and semi-volatile organic compounds. 2.1.1 Borehole Drilling The boreholes will be drilled with a GeoProbe rig owned and operated by V&W Drilling of Isleton, CA (C57# 720904). The GeoProbe advances a coring tool with a pneumatic hammer to a selected depth. The soil sample enters an acetate cylinder contained in the coring tool. Upon filling, the coring tool is pulled from the hole and the cylinder is removed. The cylinder is then cut and the selected interval is capped with Teflon foil and plastic end caps, labeled and placed in a cooler for transport to the laboratory following Chain of Custody protocol. The remainder is used for geologic logging. The boreholes will be closed using grout slurry. Nine GeoProbe boreholes will be advanced in the locations indicated in Figure 2. Soil samples will be collected on a continual coring basis to desired borehole depth. A boring log providing sediment description using the USCS and field observations will be maintained by a professional geologist working under the supervision of a registered geologist. All soil samples will be sealed with Teflon, capped with end caps, labeled and placed in a cooler for transport to the laboratory following Chain of Custody protocol. Since only selected soil samples collected will be submitted for laboratory analysis, a screening process will be used to gather additional information through field observation. These observations will include: • Sediment type, especially grain size and clay content • Moisture content • Visible evidence of contamination, i.e., color change due to reduction of iron or discoloration from hydrocarbons and other pollutants • Readings above background on an organic vapor meter(OVM) The OVM is a portable photo ionization detector that uses a 10.6 eV lamp to detect compounds with ionization potential below 10.6 eV (hydrocarbon range). Contingency Plan: If the cleanout and inspection of the two septic tanks show that no cracks or holes are present in the walls of the tanks, then the boreholes proposed to be drilled under the two tanks will not be drilled and the samples will not be collected or analyzed. This will be a considerable cost savings.