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Y above the occurrence of groundwater to observe for floating product. The sand pack was �.,. placed to a point about two feet above the slots. A bentonite seal was placed atop the sand pack, and a cement grout seal placed atop the bentonite using a tremie line, filling from the bottom to top of the borehole annular space. A traffic rated wellhead access box and security device completed each well. Well Head Survev All wells were surveyed to mean sea level using a known datum. This allows accurate measurements and groundwater gradient to be calculated. Monitoring Well Sampling and Development All monitoring wells were developed to remove the drilling muck, grade the sand pack and provide a more complete hydraulic connection to the aquifer. The well volume was calculated and a number of those volumes were removed until the water became clear and the amount of sand pumped was minimal. Groundwater Monitoring Well Sampling Each monitoring well was purged using calculated well volumes based upon the depth to water in each casing. Depth to groundwater measurements were made to the nearest one- one hundredth of one foot, and also checked for the presence of separate phase product. As each purge volume is removed, measurements of pH, electrical conductivity and temperature were taken until these parameters stabilize, which is interpreted to be aquifer water entering the casing. The sample was carefully collected with a clean bailer and poured into the appropriate laboratory prepared container with minimum cavitation. Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice. Upon completion of well sampling, the well was closed and locked. Subsurface Conditions Eight exploratory borings were drilled at the locations shown on Figure 1. The deepest of which was advanced to a termination depth of 45-feet. Moderate to severe flowing of sandy strata occurred during drilling of Borings B-6, B-9 and MW-1. A gravelly to sandy clay and silty clay extends from the surface to depths of 8- to 12-feet. These upper strata are underlain by interbedded clayey silt and sandy clay to depths of 14- to 16-feet. Some staining and slight petroleum odor was observed in MW-3, which was placed between the two former tank pits. Silty sand to sand underlie the clayey silt and sandy clay to depths of 15 to 16-feet. A clayey sand and sand occur from 15-feet to 25-feet and compose the aquifer strata. A clay strata observed in B-10 and MW-2 appear to be correlative and this clay strata extends to a depth of at least 46- feet. This strata is �..� in a similar stratigraphic position as that reported on the water well driller log. The strata below 26-feet did not yield water in the sediment samples from B-10. Page 4