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v � approximately 12 feet below ground surface (bgs) and the pits were backfilled. Petroleum hydrocarbons were detected in the fifth test pit starting at a depth of approximately four feet bgs. In an attempt to define the extent of the spill, impacted soil was excavated until the sidewalls of the pit exhibited no evidence of petroleum hydrocarbons. Soil was excavated to a depth of approximately 14 feet bgs, the estimated depth to groundwater. ATC collected confirmation samples from the excavation sidewalls and bottom. A grab sample was collected from the groundwater after it seeped into the excavation. Excavated soil was stockpiled on visquene plastic on site. Laboratory analysis of soil samples from the first four test pits indicated TPHd concentrations ranging from nondetect to 2.2 part per million (ppm). Total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethyl benzene, and xylenes (BTEX), and methyl tertiary butyl ether (MTBE) were nondetect. Samples collected from the south and east sidewalls of the fifth test pit were nondetect. Samples from the north and west sidewalls contained low levels of TPHd, MTBE, and xylenes. TPHd was detected in the bottom soil samples at concentrations of 290 ppm and 340 ppm and low levels of MTBE, benzene, ethyl benzene, and xylenes were also detected. TPHd, MTBE, and xylenes were detected in the grab groundwater sample at concentrations of 190,000 parts per billion (ppb), 150 ppb, and 300 ppb, respectively. �j w ikry fE X)1(461 0 00 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. 109) 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 Borings To determine the extent of soil and groundwater contamination at the site, a minimum of four soil borings will be advanced to approximately 14 feet bgs, the depth to groundwater. The borings will be placed outside the excavation area. If any of the borings exhibit the presence of contamination we will step out and advance additional borings as needed. Proposed boring locations are shown on Figure 2. The 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, field screened with a Photoionization Detection (PID) meter, and at least one soil w:\82254\workplan.doc 2