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Pr Quik Stop No 121 Additional On-Site and Offsite Soil and Groundwater Investigation Page 3 7 Prepared this technical report on findings of the investigation Field Investigation Prior to beginning the field work, the proposed boring locations were cleared for underground utilities by notifying Underground Service Alert (U S A ), and retaining a private line location firm CCI conducted the field work for this investigation on June 21, 22 and 23, 2000 The field work included "direct pushing" borings using a CPT rig to collect lithology data and groundwater samples from selected on and off-site locations Cone Penetrometer Testing (CPT) A total of 3 CPT boreholes were pushed at selected locations in the vicinity of the subject site in an effort to investigate the lateral and vertical extent of petroleum hydrocarbons in the groundwater (Figure 2) The locations of the CPT data points were selected based upon sample Sdata obtained by CCI in its previous quarterly sample reports Grab water samples were collected from all three boreholes, CPT-1, CPT-2 and CPT-3 At CPT data points 1 and 2, a two-step process was used that included "sounding" each hole to collect lithology information and pore pressure data, followed by direct-pushing a separate hole to a targeted sand lens and using a hydropunch sampling device to collect a "grab" groundwater sample It should be noted that the CPT sounding cone was not functioning properly at CPT-3 Therefore, no lithology data was gathered from this location, however, a groundwater sample was collected CPT-1 and CPT-2 were pushed as deep as possible until refusal was encountered During the sounding phase, a cone-tipped, pressure-sensitive probe was attached to a string of steel rods and advanced into the ground with heavy hydraulic rams The rams, as well as the rest of the CPT equipment, were contained in a 20-ton truck The weight of the truck provided the reactive force As the rods and probe were pushed into the ground, two strain-gauge load cells contained within the probe measured the bearing and shear resistance at the tip and sides of the probe, respectively, from the soil encountered Analog signals generated by the cells in the probe were transmitted via cable to an on-board computer, where conversion into digital data occurred As the probe was advanced, the data generated by the probe were simultaneously displayed on a monitor inside the CPT rig Upon completion of the test, the soil resistance relationships were calculated by the computer to determine the soil stratigraphy The CPT data and interpreted stratigraphic results were then printed The three CPT data points were advanced to total depths of approximately of 79 feet at CPT-1, 62 feet at CPT-2 and 35 feet at CPT-3 Computer- generated logs from CPT-1 and CPT-2 are attached in Appendix A