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during sand placement, and fill was checked with a weighted tape . As the sand filled the annulus, auger flights were slowly withdrawn A total of 6 1/2 sacks of sand was used, the top was located at 281 , 2 feet above the top of the screened porton A bucket of bentonite pellets was poured down the annulus on top of the sand, it was wetted with a bucket of water The top of the bentonite seal was located at 251611 , 2 1/2 ' above the sand pack The remaining auger flights were withdrawn from the hole, they were covered with sticky, blue-grey clay. PLATE XII gives details of the well completion. All three wells were grouted from the top of the bentonite seal to the surface with a cement/bentonite slurry displaced down the annulus with a tremae pipe and flexible hose Each well was fitted with a preformed vault which was thoroughly cemented in place Casings extended approximately 6" into the vault, and were fitted with expandable locking caps . The vaults were covered with metal covers, and secured with bolts Drill cuttings and unused core materials were placed in metal drums, thoroughly sealed and labeled, and stored on location pending later disposition The preserved cores were transported under chain of custody to FGL Environmental with instructions to test for BTEX, (EPA 8020, ) TPH-G, (EPA 8015M, ) and total lead, (EPA 7420 . ) Any lead samples exceeding 50 mg/kg were to be tested for solubility, (STLC. ) Detection limits were to be in conformance with San Joaquin County EHD requirements Refer to TABLE II for a summary of the results of those analyses Laboratory reports, QA/QC, and chain of custody is included as EXHIBIT J On July 13 , 1995, Del-Tech Geotechnical Support Services developed, purged, and sampled the three wells under the super- vision of a representative of the San Joaquin County EHD. Casings were notched & marked on the north side for reference purposes water samples were delivered to FGL Environmental under chain of custody with instructions to test for BTEX, (EPA 602, ) TPH--G, (EPA 8015M, ) & purgable halocarbons, (EPA 601 . ) The last test was run at the request of Ron Rowe of the San Joaquin County EHD; they are attempting to trace the source of certain solvents found in the groundwater in this area. Details of the field work are attached as EXHIBIT K The results of the labora- tory analyses are summarized on TABLE III , copies of the lab sheets & chain of custody are included as EXHIBIT L The wellhead elevations and coordinates were determined by a • licensed surveyor, refer to EXHIBIT M for a copy of that survey 8