SITE INFORMATION AND CORRESPONDENCE

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i w Ms. Margaret Lagorio San Joaquin County July 24, 1995 Page 5 The shallower soil samples will be analyzed for TPH with characterization of peaks. The deeper samples will be used to identify petroleum impact to soils visually. Four-Inch Pipe A steel pipe, four inches in diameter and filled with dirt, is located immediately north of the office in front of the fab shop. This pipe may be a sewer clean-out, but actual usage is unclear. The pipe will be cleaned out to the extent feasible and possible usage evaluated. One soil gas sample will be collected in the immediate vicinity of the pipe and field screened with a PID. No other sampling is anticipated for this location. Dry Well According to FR Manufacturing personnel, a 25- to 30-foot deep dry well is located in the parking area near the northeast corner of the fab shop. The dry well was discovered during grading for repaving and was reportedly backfilled with pea gravel and paved over at FR Manufacturing's direction. Water is not anticipated to be present in the well itself. The history of the dry well is unknown, however it could have been used for disposal of liquids when the site was a fig orchard or after the manufacturing facility was in operation. The well will be located using historic aerial photographs and surface geophysical techniques. Once the well has been located, a soil boring will be drilled immediately adjacent to it. A soil boring or Geoprobe will not be advanced through the well due to the difficulty of drilling through coarse gravel backfill. Soil gas will be sampled and field screened using a PID; and a soil sample will be collected every ten feet to groundwater, starting at 30 feet bgs to evaluate the presence or absence of chemicals in the unsaturated zone. One groundwater sample will be collected using the Hydropunch technique. The soil sample collected at 30 feet and the groundwater sample will be analyzed for VOCs, pesticides, TPH with characterization of peaks, and 17-Title 22 metals. The remaining soil samples will be analyzed for pesticides and VOCs. The groundwater sample will also be analyzed for herbicides. Capped, Inactive Well An eight-inch steel pipe or casing with a welded steel cap was found in the parking area in front of the main office. The pipe resembles a well casing, but was reported by occupants as a sewer cleanout for a former watchman's trailer. Because of the potential presence of methane gas from sewage, a small hole will be drilled through the pipe and the atmosphere within the pipe tested with a lower NBIHYDRO-SEARCH, i IC. A Tetra Tech Company