SITE INFORMATION AND CORRESPONDENCE FILE 1

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Geological?ecknics Inc. Page 2 Valentine(Castle Motors) Vertical Def.WP August 23,2000 The following procedure will be used to drill the deep borehole. A set of 10-inch hollow stem augers will be drilled down to a depth of approximately 50 feet. The augers serve to provide a return conduit for the drilling mud and to isolate the drilling mud from the heavy contamination in shallow soil. A 6-inch diameter rotary bit is then lowered down the inside of the augers and drilling progresses. The drilling mud will be a mix of bentonite gel with a small amount of polymer added to aid in reducing loss of drilling mud to the formation. The mud is pumped down the inside of the drill rods and up the borehole. A portable mud pit is placed around the 10-inch augers to catch mud and cutting as they come out of the hole. The drilling mud is continually reused during the drilling process. The mud rotary rig is owned and operated by V&W Drilling (C57# 720904). A drilling permit will be secured as necessary and the local regulatory agency will be notified 48 hours prior to commencing work. The subsurface will be cleared of underground utilities by notifying Underground Service Alert. 2.1.1 Soil Sampling Procedure Borehole MW-201 will be free drilled to a depth of 110 feet since it will be drilled adjacent to MW-101/SB-201 (logs on file). To better define the geology in the drilled interval, the borehole will be continuously logged from 110 feet to final 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. For geologic description, soil samples will be collected in 6.0-inch brass liners using a 2.0- inch modified California split spoon sampler. Soil samples to be tested in the laboratory will be collected using the SimulProbe as described below in Section 2.2. All soil samples for laboratory analysis will be sealed with Teflon, capped with Teflon end caps, labeled and placed in a cooler at 4° Celsius 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 10.0 eV lamp to detect compounds with ionization potential below 10.0 eV (hydrocarbon range). 2.1.2 Soil Laboratory Analyses Based on field screening observations up to five soil samples from MW-201 will be submitted to CLS Laboratories (State Certified Laboratory #1233). Samples will be analyzed for the following: