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Nftwow <br /> Soil Boring and Monitoring„Well Installation <br /> Smith Technology will supervise the advancement of three soil borings, collect soil samples, and <br /> complete three of the borings as monitoring wells. The analytical results of soil and groundwater <br /> samples obtained during Phase One of the subsurface investigation will help determine the <br /> location of the monitoring wells. <br /> The borings will be advanced to depths of approximately 30 feet using a hollow stem auger <br /> equipped drill rig. Drilling will be conducted by a State-licensed (C57) drilling company. A field <br /> geologist will be present to log all drill cuttings and soil samples. Descriptions of soil types <br /> encountered and sample collection intervals will be recorded on boring/well logs. Soil samples <br /> will be collected at five-foot intervals or at changes in lithology, field screened with a PID, and at <br /> least two samples from each of the three borings will be submitted for laboratory analysis. All <br /> drill cuttings will be drummed and stored on site pending laboratory results. <br /> Well Construction <br /> The borings will be completed as groundwater monitoring wells. The monitoring wells will be <br /> constructed of 2-inch inside diameter schedule 40 PVC well screen and casing. A 0.020-inch well <br /> screen slot and No. 8 SRI supreme sand pack will be used. Neat cement will be used to seal the <br /> wells in accordance with California Well Standards (December 1981). To protect the integrity of <br /> the wells, locking, water-tight well plugs will be installed on each well and a water-tight wellhead <br /> labeled "monitoring well" will be concreted over each well. Proposed well construction details <br /> are shown on Figure 3. The top of casing of the new wellheads will be surveyed to assess <br /> groundwater gradient and flow direction. <br /> Soil Sample Analysis <br /> Selected soil samples will be immediately placed on ice and delivered under chain-of-custody <br /> documentation to a State-certified laboratory for analysis. Samples will be analyzed for TPHg, <br /> BTEX, oxygenate fuel additives, and total lead. <br /> Well Development and Groundwater Sampling <br /> Measurement of depth to water in all wells will be completed to evaluate the direction and <br /> magnitude of the groundwater gradient beneath the site. The new wells will be developed using <br /> surge and bail techniques until the produced water is relatively sediment free. Prior to the <br /> collection of groundwater samples, a minimum of three well volumes (casing and sand pack) will <br /> be purged. Temperature, pH, water elevation, and electric conductivity will be measured and <br /> allowed to stabilize. Water samples will be collected using disposable bailers, one dedicated to <br /> each well. <br /> Groundwater samples collected from all monitoring wells will be submitted using chain-of- <br /> custody record to a State-certified laboratory. Groundwater samples, three total, will be analyzed <br /> wA909543\r"rts\wkp.d" 4 <br /> • <br /> SR*H <br />