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C\YATC A S S O C I A T E S I N C M►WI On July 18, 1995, Smith Technology supervised the installation of three groundwater monitoring wells, MW-1, MW-2, and MW-3 (Figure 2). During installation of the monitoring wells, soil samples were collected from the borings. On July 21, 1995, Smith Technology developed and sampled monitoring wells MW-1, MW-2 and MW-3. Analytical results of the soil and groundwater samples collected indicated elevated concentrations of petroleum hydrocarbons were present in the soil and groundwater downgradient of the former gasoline UST locations. On September 24 and October 2, 1996, Smith Technology conducted an additional subsurface investigation at the site. A total of 9 soil borings were advanced to depths up to 15 feet below ground surface (bgs). Soil, soil vapor, and groundwater samples were collected from the borings. Analytical results of the soil and groundwater samples indicated the general extent of total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene, and xylenes (BTEX), and methyl tertiary butyl ether (MTBE) in soil and groundwater under the site. Analytical results for geochemical parameters in soil and groundwater indicated bioremediation was occurring in the plume of petroleum hydrocarbons in groundwater beneath the site. Analytical results of soil vapor samples indicated the availability of oxygen, carbon dioxide, nitrogen and methane in the vadose zone. SCOPE OF WORK Planning and Permits ATC has completed the well installation permit application for the proposed subsurface investigation. The permit application and associated fees (check no. 187) are attached to this workplan. ATC will also schedule field personnel and equipment, notify Underground Service Alert to locate underground utilities as required, and perform any other necessary field preparation and job start-up activities. Installation of Soil Borings and Monitoring Wells The soil borings will be advanced using a hollow stem auger equipped drill rig to depths of approximately 28 feet bgs. Drilling will be conducted by a State licensed (C57) drilling company. The soil samples will be collected at five-foot intervals or significant changes in lithology. A field geologist will be present to log all drill cuttings and soil samples. Each soil sample will be field screened with a Photoionization Detection (PID) meter or similar instrument and at least two samples from each of the three borings, based on field observations (i.e. odor, discoloration, PID readings), will be placed in a cooler with ice and submitted for laboratory analysis. Placement of Borings and Wells To evaluate the extent of soil and groundwater contamination in the area northwest of the former USTs, three soil borings will be advanced to approximately 28 feet bgs. One boring will be wA17861\rep0rtS\wkpwei.d0c 2