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y a five-foot intervals, with additional samples collected at intervals of obvious contamination and at stratigraphic features of interest using field discretion. Upon completion of the borehole drilling and collection of information, all boreholes were backfilled with grout, placed from the bottom to top of the borehole with a tremie line. Reconnaissance Groundwater Sampling Groundwater from each borehole drilled on July 23, 2001 was sampled using push or drill rods or hollowstem auger as temporary casing in the uppermost aquifer. Depth to groundwater measurements were made to the nearest one-one hundredth of one foot from existing grade, and also checked for the presence of separate phase product. The groundwater sample was carefully collected with a clean disposable bailer and poured into the appropriate laboratory prepared container with minimum cavitation and headspace. Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice. Off-site Water Well Sampling Domestic water for the M & M Builders lavatories is obtained through an agreement with Calaveras Cement from the property owners to the west, who has an industrial well used in concrete batch operations. Wright's scope of work included collection of water samples from the Calaveras Cement well (Water Well), located at 8181 1 lth Street (just east of and adjacent to the M&M warehouse building). The Water Well sampling used the faucet near the wellhead and the existing pump in the well. The water sample was collected after first clearing the faucet for thirty seconds, then filling the laboratory prepared containers container with minimum cavitation and headspace. The water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice. The PHS EHD representative witnessed a portion of the water well sampling. Data Review and Monitoring Well Positioning Wright provided the chemical data collected from Borings B-6 through B-10 for their review. Wright proposed the locations of three groundwater monitoring wells based upon this data, which PHS EHD approved for well installation on August 28, 2001 under the same permits. Monitoring Well Installation Three monitoring wells were installed on August 28, 2001. The wells were cased with Sch. 40 PVC casing, threaded together; glues were not used. The slotted interval used a 0.020-inch slot and the annular spaces around the slots were backfilled with a 2/12-size sand. Previous experience has shown this to be a reliable well design in fine grained and stratified depositional environments. Final well design was modified to the site-specific �..� conditions encountered in the borehole during drilling. Once the aquifer strata had been defined, the casing was lowered to the bottom of the borehole, leaving a slotted interval Page 3