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. The boreholes were logged using the Unified Soil Classification System under the supervision of a registered geologist Additional lithologic information was collected to describe the subsurface geology Soil samples were field screened for presence of contaminants by checking for presence of odor and staining A photoioruzation meter malfunctioned in the field and was unavailable for field vapor measurement use Soil samples were collected at minimum 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 Reconnaissance Groundwater Sampling Each borehole was sampled using push or drill rods as temporary casing 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 cavitations Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice Subsurface Conditions • Six exploratory borings were drilled at the locations shown on Figure 1, which revealed a relatively complex stratigraphy The borings revealed sandy clay to depths of about 5- to 6-feet An excavation backfill was observed in Boring B-1, which extends to a depth of 7- to 8-feet Minor petroleum staining or odor was observed in the capillary fringe vicinity in boreholes B-1 and B-2 Interbedded sand, silty sand and sandy silt beds between depths of roughly 8-to 15-feet underlie these clayey strata The first observed groundwater in these strata occurs at depths of 8- to 10-feet Sandy silt and sand occur next and extend to depths of 18- to 22-feet Clayey sand, sandy silt and sandy clay strata occur below 18-feet and compose the lower confining strata These strata are locally cemented and the auger/push casing encountered refusal at or near the 20-foot depth Flowing sandy strata occurred during drilling in some holes, which made sample recovery difficult, and in some cases, losing soil samples Page 3