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• approximately 25 feet below grade (or 10 feet below the water table) . Soil borings will be advanced at locations indicated on Figure 1 using hollow-stem auger drilling techniques. Soil samples will be collected as the borings are advanced at 5-foot intervals and/or changes in lithology. The samples will be screened in the field for the presence of organic vapors with a photoionization detector (PID) . Soil cuttings will be stored on site on plastic pending receipt of analytical results and characterization for disposal. One soil sample collected above the water table from each soil boring will be submitted to a state-certified laboratory for analysis of BTEX and TPHg. All analyses will be done using established state and federal EPA methodology. Drilling and sampling protocols are described in Appendix A. Monitoring Well Construction, Depth to Water Measurements, and Ground Water Sampling Proposed monitoring wells will be constructed with 15 feet of 2- inch diameter polyvinyl chloride(PVC) well screen with 0. 020-inch wide (#20) slots. Blank 2-inch diameter PVC will extend from the top of the screen to the surface. The annular space opposite the screened portion of the well will be backfilled with a gravel pack consisting of #3 Monterey sand or equivalent. The gravel pack will . extend 2 feet above the top of the screened interval. In the annular space above the gravel pack, a 2-foot thick bentonite seal will be installed. Above the bentonite seal, a cement grout with approximately 5 percent bentonite will be emplaced and will serve to inhibit movement of surface water downward through the well annulus. The well riser will be cut off below grade and a flush- grade, watertight, well box will be installed at the surface. A watertight, locking, expansion well cap will be used to secure the well riser. A diagram of typical well construction specifications is included as Figure 2 . After installation, the casing riser on each well will be surveyed relative to the existing on-site monitoring wells. Depth to water in each well will then be measured, and each monitoring well will be developed, purged, and sampled as described in Appendix A and in accordance with (Santa Barbara) County requirements. Purge water wi be stored on site in approved 55-gallon drums pending disposal. The groundwater samples will be submitted to a state- certified laboratory for analysis of BTEX and TPHg. Report Results After field activities are complete and after receipt of laboratory results, ,a report of� the results will be prepared to,document field activities, present the ` analytical Iresults�,, 'and recommend ' I 1 1 I II I• additional work, l if warranted. The report will include soilh boring ' logs, soil sample analytical results, subsurface; soil descriptions, f depth tolwater lImeasurements, and groundwater sample 'analytical results. I The final report will be signed and sealed by a I ' I I 1'1 , I'I 111 Esq'''