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Amended Workplan for n/Jerni an - 03/20/98 Page 2 of 2 ONE PROPOSED BOREHOLE The proposed work encompasses a 40 foot deep borehole utilizing an eight inch diameter hollow stem auger which will be continuously sampled from a depth of 20 to 40 feet below ground surface (see figures map views and cross sections for relative borehole location). A minimum of five samples will be collected and analyzed for TPHg/BTEX/MTBE constituents and TCLP leachability. The goal will be to establish a decreasing trend in benzene concentrations with depth so that the deepest sample confirms a non-detectable concentration. The borehole will be extended to greater depths if obvious contamination is still evident during the drilling and sampling process. SOIL SAMPLING All drilling and soil sampling procedures stipulated in the approved workplan will be followed for the work necessary to complete the proposed borehole. CONTINGENCY FOR ENCOUNTERING GROUNDWATER Based on the well survey performed, the possibility of encountering groundwater, is at best, remote. If perched groundwater is encountered, however, a determination will be made in the field to establish if it is productive enough to be considered a "Water of the State." If the perched water is determined to be a local anomaly, then a groundwater grab sample will be collected according to the procedures established in the approved workplan. If a viable groundwater resource is encountered, the borehole will be converted to a standard groundwater monitoring well (see generalized well construction detail), after the client's approval. If a monitoring well is installed, the well would be properly purged and developed and water sampling would be performed after the groundwater had stabilized several days later. A water level measurement would then be performed and the water sample would be collected with a stainless steel check valve bailer after three consecutive readings of temperature, conductivity, and pH are within a 10% difference. Samples would be analyzed for TPHg/BTEX/MTBE. DISPOSAL OF SOIL CUTTINGS, WATER RINSi:ATE, AND MONITORING WELL PURGE WATER All soil and water wastes will be place in 55 gallon drums and properly labeled for laboratory profiling and transport to a legal point of disposal.