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Geofogica[TecFin Inc. Page 2 U.S. Can Company Soil and Groundwater Investigation Work Plan Project No. 397.2 August 9, 1996 2.0 PROPOSED INVESTIGATION To further investigate the vertical and lateral extent of soil impacted with volatile organic compounds, Geological Technics Inc. proposes to advance (4) soil borings surrounding the point of release. One boring will be converted into a groundwater monitoring well (Figure 2 Site Map). 2.1 Soil Borings Prior to commencing work soil boring/monitoring well permits will be secured and the SJCPHSEHD will be notified 48 hours in advance. The borings will be drilled using a 8.00 inch outside diameter continuous flight hollow stem auger owned and operated by V&W Drilling (C57# 720904). The subsurface will be cleared of underground utilities by notifying Underground Service Alert. The soil borings will be extended to the capillary fringe. The expected depth to groundwater in this area is approximately 10 feet below grade, based on information from the 1986 San Joaquin County Flood Control Map, Lines of Equal Depth to Water in Wells. However information presented in the Geological Technics Inc. February 6, 1995 Preliminary Environmental Site Assessment Report for the 35500 Welty Road Property in Vernalis (approximately 700 ft southeast) shows that the depth to groundwater was (33) feet below grade in January 1995. It is proposed to drill SB-1 using continuous coring methods for the purpose of evaluating the subsurface geologic condition. This core will be kept for future references. The boreholes will be closed by pumping a neat cement grout containing <4% bentonite to grade, using a grout pump and tremie pipe. Clean soil cutting will be stockpiled and obviously contaminated soil cuttings may be underlain and covered with plastic and segregated from the clean stockpile or containerized in D.O.T. approved 55 gallon steel drums. 2.2 Soil Sampling Procedure Soil samples will be collected for geological and analytical evaluation at five foot intervals. A boring log providing sediment description using the U.S.C.S. and field observations will be maintained by a professional geologist working under the supervision of a registered geologist. Soil samples will be collected in 6.0 inch brass liners using a 2.0 inch modified California split spoon sampler. All soil samples will be sealed with aluminum foil or Teflon sheets, capped, labeled and placed in a cooler at 4° Celsius for transport to the laboratory following Chain of Custody protocol. Because every soil sample collected will not be submitted for laboratory analysis, a screening process will be used to gather additional information through field observation noting 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, and the readings above background on a organic vapor meter (OVM). The OVM is a field portable photo ionization detector that uses a 10.0 eV lamp to detect compounds with ionization potential below 10.0 eV (hydrocarbon range).