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Geolog ical7"eeluuea Inc Page 4 Site Characterization Report Project No 724 2 • May 9,2006 as the cone moves downward and these values can be correlated to determine the type of soil present Prior to commencing work, encroachment & soil boring/monitoring well periluts were secured from the City of Stockton and the SJC/EHD The SJC/EHD was notified at least 48 ' hours in advance The subsurface was cleared of underground utilities by notifying Underground Service Alert ' On February 21 thru 23, 2006, Test America Inc of Anaheim, California mobilized to the site to perform the CPT boreholes The depth to water on February 21, 2006 was approximately 32 5 feet below grade surface (bgs) as measured in well MW-5 by GTl staff ' The CPT testing began with the proposed CPT-1 borehole - see Figure 3 for borehole locations The CPT and sampling boreholes were hand augured to a depth of 5 feet to clear 1 for underground utilities and then the CPT boring commenced This initial CPT borehole met refusal at approximately 74 5 feet bgs with the 20 ton drill rig lifting off the ground The rods were removed from the ground and then a sacrificial well screen was attached to the lead ' section The rods were inserted in the same borehole and a groundwater sample was successfully attempted at a depth of 75 — 77 feet bgs The rods were removed and then the rig moved three feet to a new sampling hole location Soil and groundwater samples were successfully obtained from this hole The rest of the CPT locations were addressed in a similar fashion with a CPT borehole advanced until refusal was met, try to obtain a terminus ' water sample if present in this same hole, then move the rig several feet and advance a sampling borehole for the purpose of obtaining discrete water and soil samples The work is summarized as follows 1 • CPT-1 was placed approximately 50 feet north of the centerline of E Hampton Street in the El Dorado Street east parking lane This borehole encountered refusal at 74 5 feet bgs, successfully attempt water sample in same hole at 75 - 77' bgs, move rig to a new sampling borehole location and attempt a soil sample at 30 — 32' but only 4" recovery due to wet sands, attempt a soil sample at 32 — 34' and again only 4" recovery due to wet sands, successfully attempt water sample at 34 — 36' bgs, attempt water sample at 55 -57' bgs but dry • CPT-3 was placed approximately 200 feet east of the centerline of El Dorado Street in the E Hampton Street south parking lane This borehole experienced refusal at 70 5 feet bgs, successfully attempt water sample in same hole at 71 - 73' bgs, move rig to a new sampling borehole location and successfully attempt a soil sample at 30 -- 32', attempt water sample at 32 -34' bgs but dry, attempt water sample at 45 - 47' bgs but dry, drive rods to a total depth of 89' bgs and let sit but dry hole ' • CPT-2 was placed approximately 150 feet east of the centerline of El Dorado Street in the E Hampton Street north parking lane This borehole met refusal at 68 feet bgs, successfully attempt water sample in same hole at 68 - 70' bgs, move rig to a new sampling borehole location and successfully attempt a soil sample at 27 —29', attempt