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i I The hydraulic casing, which contained the piston used to move the elevator car, was located in a seven-inch diameter soli boring with no secondary containment. The length of the hydraulic sleeve which was buned within the elevator pct area is approximately 12 feet. Upon removal of the hydraulic sleeve, oil saturated soil was observed It appears that either during removal of the hydraulic sleeve and piston or sometime later. there was partial collapse of the hole. I CRC performed a limited subsurface investigation in the area of the elevator pit in February of 1994 The objective of the subsurface soil investigation and the groundwater sampitng was to determine the extent of soil and groundwater contamination, both laterally and vertically, and to further investigate remediation options. The preliminary site characterization indicated that the majority of hydraulic fluid contammatton is in the upper 6 feet of soil immediately below the bottom of the elevator pit. The bottom of the pit is approximately 4 5 feet below grade. Three core probes were drilled in the floor of the elevator pit, an area approximately 6 5 feet by 9 5 feet, and three cores were drilled outside the elevator pit area from 10 to 20 feet from the central source CRC's environmental investigation revealed that there was impact to the groundwater m a radius of approximately 10 to 12 feet from the source, and that the upper ten feet of the soils below the elevator pit were saturated with hydraulic fluid. CRC reviewed regional groundwater direction in the area and groundwater was expected to be approximately 25 feet below ground surface (bgs), however, groundwater was less than 10 feet bgs Regional gradient is suspected as being northeast; however, gradient has not been established at the site Because a btulding exists on the east side of the elevator pit, it was not possible to place test borings in an easterly direction relative to the source SCOPE OF WORK a) Soil remediation in the elevator Rit by au erin Remediation will be performed by augering into the contaminated soil by means of a portable drill ng using both a 24-inch and a 10-inch diameter auger to a depth of approximately 10 feet below the bottom of the elevator pit. Groundwater is anticipated at 10 feet or less within the elevator pit. therefore, augermg will be terminated at 10 feet. Soils generated during excavation will be transported and disposed of under manifest to a disposal facility Up to fifteen (15) 24-inch diameter borings along with in-fill 10 inch diameter borings will be excavated in order to remove the maximum amount of soils under the elevator pit floor Confirmatory samples will be collected every 5 feet in the corner borings and analyzed to ascertain remairung levels of hydraulic oil contamination Analvsis performed on the soil samples will be Total Extractable Hydrocarbons by California LM modified Method 8015 using a sample of the hydraulic oil as the standard CRC Enrmm*~ws Risk Mangao LL inc Pt2523-017.1 3rams Puim s L P .:33 Glad Caa1 8611111VOIN Tar l 1 1994 Stockw&Callfams