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The soil samples were immediately sealed in the liners using teflon tape and plastic caps, labeled, and immediately placed on ice for transport to our laboratory under chain-of-custody documentation. Soil cuttings derived from the boring were retained and stored on-site during the drilling and well construction and subsequently placed at the northeast corner of the existing soil stockpile area ( located adjacent to Monitoring Well #5) . Subsurface Conditions The soils encountered in the borings were visually classified in the field under the supervision of a State of California certified engineering geologist in accordance with the Unified Soil Classification System (Figure 2) . A boring log depicting the subsurface conditions is presented on Figure 3. The soils at the site, as encountered in our boring, consisted of alluvial sand, silt, and silty sand with interbedded lenses of gravelly sand, and clayey silt. Groundwater was encountered during drilling at an approximate depth of 50 feet in a gray, silty to coarse grained sand. This unit was underlain by thin layers of silty sand, sand, and silt. A dense silty sand unit was encountered at 60 feet. The boring was terminated in the silty sand layer. Monitoring well Construction Following completion of the boring, an open standpipe piezometer well was constructed by installing 2-inch diameter polyvinyl chloride (PVC) flush-threaded casing and slotted pipe directly through the hollow stem auger. The slotted section of the PVC pipe installed through the saturated zone had 0. 020 inch factory perforations. Materials used in the well construction were thoroughly cleaned prior to introduction into the boring. The monitoring well was filter-packed with clean #2/#12 Monterey silica sand placed throughout the screened interval. The filter-pack material was installed in the annular spacing between the monitoring well pipe and the auger as the auger was removed. The filter pack extended a minimum of five feet above the top of the screened interval. A three foot thick layer of bentonite was placed above the filter material to provide an annular seal. The remainder of the boring was filled with a cement slurry to within one foot of grade. A locking cap and a concrete encased watertight aluminum traffic box was installed flush with the ground surface. Figure 4 illustrates the construction of the monitoring well. BSK - 2 - &Associates