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eQtember 5 2001 depths approximately 2,000 feet below ground surface (bgs). Units underlying the Site, with respect to increasing depth, include the following: • The Holocene Younger Alluvium • The Pleistocene-Holocene Older Alluvium • The Pleistocene Turlock Formation • The Pliocene Laguna Formation • The Pliocene Mehrten Formation, and • The Miocene Valley Springs Formation The Younger Alluvium, Turlock Lake, and Laguna Formations consist of sediments (sands, gravels, silts, and clays) comprised mainly of granitic source materials. The Mehrten Formation is characterized by black volcanic sandstones and conglomerates with interbedded dark-colored mudstones and volcanic mud flow deposits. The Valley Springs Formation overlies deeper marine and continental deposits and consists of rhyolitic-volcanic sandstones, mudstones, and ash to tuffaceous beds. The source of groundwater in the Site area is predominately the Tertiary and Quaternary Continental rocks and deposits, which consist of the overlying alluvium, the Turlock Lake, and the Laguna Formations. 3.2 Local Geology and Hydrogeology Subsurface sediments in the Lodi are comprised mainly of sands with discontinuous lenses of clays and silts to a depth of approximately 100 feet bgs. The groundwater flow direction in the Site area is reported to be generally southerly with fluctuations to the southeast and southwest. Depth to groundwater in the Site area has been reported to be approximately 40 to 50 feet bgs in the recent past. 4.0 WORKPLAN E2C, Inc. proposes to assess existing soil and groundwater conditions at and adjacent to the Busy Bee property by advancing soil borings and collecting soil samples and `grab' groundwater samples and having the samples chemically analyzed. 4.1 Soil Boring Depths and Locations A total of six (6) soil borings as shown on the attached figure are proposed to assess current soil conditions at the Site. For the purposes of this plan, it is assumed that five (5) of the borings will be vertically advanced to groundwater, approximately 40 to 50 feet bgs. The sixth boring will be advanced using a hand auger inside a small shed. The expected total depth of this hand-auger boring is approximately 20 feet bgs. If this boring is unable to be advanced, this boring will be advanced outside the shed at an angle using the drill rig. 4.2 Boring Methods The borings will be advanced using a truck-mounted hollow-stem auger drill rig with a six-inch or larger diameter hollow stem continuous flight auger in accordance with ASTM Method D 1452- 80 for soil investigations and sampling by auger borings. The augers will be steam cleaned 3 EZC Remediation, LLC