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i-C\VATC 11�j preparation and job start-up activities. A private locating company will also be utilized due to the presence of utilities in the vicinity of the proposed well. Installation of Soil Borings and Monitoring Wells The soil borings will be advanced using a hollow stem auger equipped drill rig to depths of approximately 30 feet bgs. Drilling will be conducted by a State licensed (C57) drilling company. The soil samples from the soil boring will be collected at five-foot intervals or significant changes in lithology. A field geologist will be present to log all drill cuttings and soil samples. Each soil sample will be field screened with a Photoionization Detection (PID) meter or similar instrument and at least one sample from the boring, based on field observations (i.e. odor, discoloration, PID readings), will be placed in a cooler with ice and submitted for laboratory analysis. Placement of Borings and Wells To evaluate the extent of soil and groundwater contamination in the area of the former UST, one soil boring will be advanced to approximately 30 feet bgs. The boring will be located near the northeast corner of the pumping plant. The estimated groundwater flow direction is to the north- northeast based on groundwater gradient data from monitoring of the existing wells. The proposed well location is shown on Figure 2. Groundwater Monitoring Wells Construction Details The soil boring will be completed as a groundwater monitoring wells. The monitoring well will be constructed of 2-inch inside diameter schedule 40 PVC well screen and casing. A 0.020-inch well screen slot and #2/12 mesh sand pack will be used. Neat cement will be used to seal the well in accordance with California Well Standards (December 1981). To protect the integrity of the well, a locking, water-tight well plug will be installed on the well and a water-tight wellhead labeled "monitoring well" will be concreted over the well. Proposed well construction details are shown on Figure 3. The top of casing of the existing and new wellheads will be surveyed to assess groundwater gradient and flow direction. All drill cuttings will be stored on site in 55-gallon drums pending laboratory results. Sample Analysis Selected soil samples will be immediately placed on ice and delivered under chain-of-custody documentation to a State-certified laboratory for analysis. Samples will be analyzed for total petroleum hydrocarbons as diesel (TPHd) by EPA Method 8015. Well Development and Groundwater Sampling Measurement of depth to water in all wells will be completed to evaluate the direction and magnitude of the groundwater gradient beneath the site. The new well will be developed using wA62574.051reportc\wkpwel.do 4