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' Mr.Marty Hartzell February 16,2001 Page 4 of 8 '1. . Groundwater was first encountered at a depth of approximately 60 feet bgs in borings SB 1 and ' SB4. Subsequent depth to water measurements indicated that the water had remained static at that depth. A discrete groundwater sample was collected from borings SB 1 and SB4 using a HydroPunchTM sampling tool. Spectrum drove the sampler to the desired depth, then pulled the rods up several feet to expose the screen to the formation. A stainless steel bailer was then lowered ' through the rods to the bottom of the sampler. Water samples were collected and dispensed directly into the appropriate sample containers. The samples were placed into an ice chest cooled ' to a temperature of 4° Centigrade and transported under chain-of-custody to Argon Labs for analysis. ' The completed borings were backfilled to the ground surface with neat cement grout. All down- hole drilling and sampling equipment was decontaminated using a steam cleaner. Soil cuttings and rinsate generated during drilling activities were placed in labeled DOT approved 55-gallon drums. ' The drums are stored on site pending the results of analytical sampling and determination of appropriate disposition for the waste stream. 4.0 RESULTS OF INVESTIGATION 4.1 Subsurface Conditions Soils encountered beneath the site generally consisted of interbedded units of sand, silt and clay. Soil encountered from the ground surface to approximately 13-18 feet bgs consisted primarily of clay with some silt, although soil encountered to approximate 13-15 feet bgs in boring SBI appears to be imported fill material. Underlying the fine grained soils, a laterally continuous unit ' of sand persists to a depth of approximately 38 feet bgs, although an apparent clay lens within this unit was encountered in borings SBI and SB3 from approximately 23-28 feet bgs. Interbedded silts and clays exist from approximately 38 feet bgs to at least 60 feet bgs, the maximum depth explored. An apparent sand lens was encountered within this lower unit in borings SBI and SB4 from approximately 43-48 feet bgs. Groundwater was first found at a depth of approximately 60 feet bgs. ' Strong petroleum hydrocarbon odors were noted in boring SBI in silty soil at a depth of approximately 40 feet bgs. Moderate odors were noted at depths of approximately 15 feet bgs (silt) ' and 25 feet bgs (clay), and slight odors were noted at depths of approximately 20, 30, and 45 feet bgs (all sand units). No discernible odors were present above 15 feet (fill) or below 45 feet (clay and silt). FID readings generally correlated to observed odors, with readings of 200-500 parts per million (ppm) at depths of 15, 25, and 30 feet bgs, and a reading in excess of 10,000 ppm at approximately 40 feet bgs. No odors were discernible in any samples collected from borings SB2 or SB4, although the sample collected at a depth of 40 feet bgs in boring SB3 had slight to moderate ' petroleum odors(FID of 200 ppm). Soil boring logs are included in Attachment 1. ' detalgrounulgonza[esLtiianrpt.doc