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grout. Hydro-Punch sample locations are shown in Figure 2 . Groundwater samples obtained with the Hydro-Punch apparatus will be screened in the field with a Photo Ionization Detector (PID) . This process will allow for the assurance that the outer sample locations actually extend beyond the boundary of the plume. In the event that the PID meter does detect organic constituents in the outermost sample locales, additional Hydro-Punch sample locations will be added to the program until the plume has been delineated. Phase II: Installation of Groundwater Monitoring Wells Based upon review of sample analysis data for the Hydro-Punch samples, an addendum to this report will be submitted to the CVRWQCB which outlines the locations of additional monitoring wells to be installed at the site. The monitoring wells will serve to verify the existence of contamination at the Hydro-Punch sample locations, to provide a means of obtaining representative groundwater samples, and to perform aquifer tests. A description of the well installation procedures is presented below. The wells to be installed at the Stockton Scavenger facility will be constructed with 2 inch diameter, Schedule 40, Poly Vinyl Chloride (PVC) casing (blank and perforated) and extend to approximately 30-35 feet in depth (based on seasonal fluctuations in depth to groundwater ranging from 17-22 feet) . Perforated zones will extend above the highest estimated water table elevation to detect the presence of floating product and to negate the possibility of the upper boundary of the water bearing zone being sealed off during periods of high water level. The borehole will be logged at five foot intervals with samples taken of the lower 18 inches of each five foot zone using a modified California split spoon sampler equipped with brass sleeves. Appropriate grades of filter pack and perforation size will be determined in the field. The sand pack will extend to approximately two feet above the perforations on the casing. Following the emplacement of the sand pack, a minimum of two feet of 1/4 inch rounded bentonite pellets will be placed above it and allowed to set after being saturated. A Volclay grout mixture will fill the remaining annular space. A PVC slip cap will be placed over the top of the casing and a locking top steel cover positioned over it. The locking cover will be situated below ground surface and encompassed by a galvanized steel christie box, the top of which will be flush with the ground surface so that the well will not be disturbed by truck traffic at the site. Figure 3 shows a graphical representation of the monitoring well design. All drill cuttings from Phases I & II of the investigation will be maintained in a lined temporary storage area until the results of laboratory analysis for a composite sample are obtained 4