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contractor will also be hired to check for the presence of underground utilities. Drilling permits will be obtained from SJCEHD. A health and safety plan will be prepared and implemented during drilling and sampling activities. Each soil boring will be hand augured or vacuum- cleared to a minimum depth of 4 feet BGS to check for subsurface utilities prior to drilling. Drilling will be performed by a C57-licensed contractor using a truck-mounted rig equipped with 8-inch diameter hollow-stem continuous-flight augers. All drilling equipment and sampling tools will be decontaminated prior to beginning the field activities. Reusable sampling equipment will be washed with an Liqui-Nox solution, rinsed with tap water, and rinsed with distilled water prior to each use. An ETIC geologist will supervise the drilling and sampling activities. Soil samples will be examined for lithologic identification in accordance with the Unified Soil Classification System and the Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), American Society for Testing and Materials (ASTM) Designation D2488 (ASTM 2000), visible signs of contamination, and observations will be recorded on a field log. A field meter will be used to monitor for organic vapors and to measure headspace vapors from soil samples. Technical guidance for the activities will be provided by a California Professional Geologist. Soil samples will be collected at 5-foot intervals for lithologic identification and laboratory analyses. The samples will be collected in clean stainless steel liners. The liners will be sealed, labeled, stored on ice in a thermally-insulated cooler, then transported and delivered to a state- certified analytical laboratory under chain-of-custody protocol. If evidence of contamination exists, then additional soil samples may be collected and submitted for laboratory analyses. The soil samples will be analyzed for TPH-g, BTEX, five fuel oxygenates (DIPE, ETBE, MTBE, TAME, and TBA), and fuel additives (1,2-DCA and EDB)by EPA Method 8260B. 3.5.2 Groundwater Monitoring Well Construction Each groundwater monitoring well will be constructed using 2-inch diameter Schedule 40 PVC casing. The total depth of each well and the slot size used in the screened portion of the wells will be determined based on the results of the direct-push subsurface investigation proposed in this work plan. The screened intervals will be selected based upon hydrogeologic data obtained during drilling. An appropriately-sized filter pack will be placed in the annular space of the borehole adjacent to the screened interval. The filter pack will be extended slightly above the top of the screened interval to allow for settlement during well development. A transitional seal, consisting of hydrated bentonite, will be placed above the filter pack in the annular space of the borehole. A grout slurry, consisting of neat cement, will be placed in the annular space above the bentonite seal to near ground surface. An inspector from the SJCEHD will observe and approve the grouting procedures. A traffic-rated vault box, expandable locking cap, and padlock will be installed to secure each monitoring well. Following installation activities, a DWR 188 Well Completion Report will be prepared for each monitoring well and submitted to the SJCEHD and the California Department of Water Resources (DWR). 9