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VYZ � . . A S S O C I A T E S I N C . SCOPE OF WORK Planning and Permits ATC has completed the soil boring permit application for the proposed subsurface investigation. The permit application and associated fees (check no. 108) 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. Advancement of Soil Borin,2s To try and determine the extent of soil and groundwater contamination at the site, six soil borings will be advanced to approximately 30 feet below ground surface (bgs). One boring will be placed in the center of the former 550-gallon gasoline tank location and one boring will be placed in the center of the former 500-gallon gasoline tank location. One boring will be placed at the north end and one boring will be placed at the south end of the former 7,500-gallon gasoline tank location. One boring will be placed approximately 15 feet downgradient from the former tank locations and one boring will be placed upgradient from the former tank locations. The anticipated groundwater flow direction is north-northeast. Proposed boring locations are shown on Figure 2. The six borings will be advanced using truck mounted Geoprobe® narrow diameter, direct push technology. Drilling will be conducted by a State-licensed (C57) drilling company. A field geologist will be present to log all soil samples. Descriptions of soil types encountered and sample collection intervals will be recorded on boring logs. Soil samples will be collected at five foot intervals or estimated changes in lithology, field screened with a Photoionization Detection (PID) meter, and an estimated two soil samples from each of the borings will be submitted for laboratory analysis. Soil sample selection will be based on PID measurements and field observations (i.e, odor and soil discoloration). One groundwater sample will be collected from each boring at the depth groundwater is first encountered, anticipated to be approximately 20 feet bgs. A Geoprobe® Screen Point 15 Groundwater Sampler will be threaded onto the leading end of the Geoprobe when the groundwater is encountered. While the sampler is advanced, O-ring seals and an expendable drive point will provide a watertight system to ensure sample integrity. When the tool has been advanced to the desired depth, extension rods will be sent downhole to brace the bottom of the sample screen as the tool casing is retracted. When the casing is retracted, up to 41-inches of screen with slot sizes of 0.004 inches will be exposed. Teflon tubing with a check valve attached to one end will be inserted down the casing until it is immersed in groundwater. Water will then be pumped through the tubing and to the ground surface by oscillating the tubing up and down. w:113099VcpafU\wkp.dm 2 w:113099Vepot1slw4.doc 3