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1.0 INTRODUCTION DECON Environmental Services, Inc. (DECON) removed four underground fuel storage tanks from the Stockton Steel Facility on December 11, 1992. This facility is located at 3003 E. Hammer Lane in Stockton, California. During the tank removal process diesel was detected in two of the eight soil samples collected from underneath the tanks. This work plan describes our proposed approach for soil remediation, which is based on overexcavation of the two "hot spots" in an effort to reduce the concentrations of diesel remaining in the soil to acceptable levels. 2.0 SITE DESCRIPTION The Stockton Steel Facility is a large steel fabrication facility owned by the Herrick Corporation. The facility had four under- ground fuel tanks at one location on the west side of the Main Shop building. The location, sizes, and contents of the four tanks are shown in Figure P1-1. The depth to first encountered groundwater in the area is approxi- mately 60 feet. Figure P1-1 also shows the locations of the facility' s three wells. These wells are used for domestic and irrigation purposes. The wells are sampled quarterly and the water from each well is analyzed for fuel compounds (TPA-Gasoline, TPH- Diesel, and BTEX) , VOCs (by EPA Method 8240 ) , and CAM-17 metals. All three wells have consistently been found to meet drinking water standards for these analytes . The locations of the eight soil samples collected from underneath the tanks are shown in Figure 2 . Analytical results for these eight samples are summarized in Table 1 . Certificates of analysis for these eight samples as well as the five stockpile samples already analyzed are included in the Appendix to this work plan. 3.0 FIELD WORK This section describes the field work that will be performed to overexcavate soil from the two areas and collect confirmation samples of the soil remaining beneath the areas that are overexcavated. 3 .1 EXCAVATION AND STOCKPILING Any standing water that may be present in the open excavation will first be pumped into a portable storage tank using a double dia- phragm pump. This water will be sampled and analyzed as described below. DECON will use a track-mounted excavator (Cat 225 or equivalent) to remove soil from the open hole in the vicinity of sample locations 02-N and 03-E. We will remove any remaining fill