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Field Procedures Three CPT borings (CP-1, CP-2, and CP-3) were advanced on October 15, 1997 at the locations shown on Plate 2 CP-1 was located at the proposed site of Well MW-12, CP-2 was located at the proposed site of Well MW-13, and CP-3 was located off-site at the proposed site of Well MW-14 A Cambria geologist was on-site to supervise the CPT activities The borings were drilled using CPT equipment which advances a probe by means of a hydraulic ram located in the center of the CPT truck The CPT equipment interprets the hthology of the boring by measuring physical qualities of the soil it is penetrating CPT probe measurements are collected and interpreted by an on-board computer, which prints out a log of the encountered hthology when the boring is completed These logs are presented in Appendix B Findings Lithology encountered in the CPT borings consisted of fine grained sediments (clay and silt) from ground surface to approximately 25 fbg in CP-1 and CP-3, and from the ground surface to approximately 15 fbg in CP-2 Coarse grained sediments (silty sand, sand, and gravely sand) were encountered beneath the fine grained sediments and extended to respective depths of 39, 28, 34 fbg in CP-1, CP-2, and CP-3 Fine grained sediments were encountered below these coarse grained sediments and were found to extend to respective depths of 75, 80, and 76 fbg in CP-1, CP-2, and CP-3 where coarse grained sediments were once again encountered The coarse grained sediments extended to the depth of approximately 85 fbg in CP-1 and were underlain by fine grained sediments to the total depth explored of 100 fbg The second coarse grained layer in CP-2 was logged as being 1 foot thick and underlain by fine grained sediments to the total depth explored of 100 fbg The second coarse grained layer in CP-3 was 10 feet thick and underlain by fine grained deposits to 130 fbg with two minor (1 foot thick or less) coarse grained layers occurring at 90 fbg and 100 fbg AQUIFER TESTING Aquifer testing was performed in Wells RW-IA and MW-2 during the period of October 27 through October 30, 1997 Two tests were performed in each well First a step-discharge test was performed in each well to determine a sustainable pumping rate for the second test, a constant-discharge test Two wells were selected for testing because the wells are constructed differently and located in different lithologic material Well RW-1A is constructed as a 6-inch diameter ground water extraction well located in the center of the former UST complex The upper section of the screened interval of this well is screened in non-native backfill material consisting of coarse gravel and silty sand It was felt that aquifer testing in this well may not accurately characterize the native water bearing material, therefore a second well (MW-2) was selected for testing Monitoring well MW-2 is located in the northern portion of the site and is constructed entirely in native soil, and therefore should accurately represent characteristics of the natural aquifer under pumping conditions 240-0783 6