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r v GENESIS ENGINEERING & REDEVELOPMENT foot of the ground surface. Based on the existing surface material, a concrete, asphalt, or soil plug will be installed at the surface of each boring location. 2.3.2 Auger Drilling Hollow-stem auger drilling technology will be used to advance the borings for installation of the Monitoring Wells. The monitoring well boreholes will be advanced using a truck-mounted drill rig equipped with hollow-stem augers. Continuous soil samples will be collected and logged to the maximum depth of the hole. The well will be constructed of 2-inch diameter, schedule 40, poly vinyl chloride casing, and machine slotted 0.010-inch screen(or other suitable size depending on the results of the sieve analyses) at the bottom. Based on the results of the CPT generated data, a ten-foot long (or shorter)well screen will be installed at the approximate depth interval of 10 feet to 20 feet below grade. The annular space around the well screen will be backfilled with clean, Monterey sand by placing the sand through the augers as they are removed from the boring. The well will then be surged to settle the sand pack prior to sealing the annular space. Additional sand will be added as needed to ensure the sand pack extends to at least 2 feet above the top of the well screen. At least 2 feet of hydrated bentonite will be placed above the sand pack. The remaining annular space will be sealed with cement grout or bentonite. The wellhead will be completed below grade and will be protected by a traffic-rated monitoring well vault with a watertight lid. Dedicated sample tubing will be installed in each monitoring well. Soil cuttings generated during drilling activities shall be monitored with an organic vapor monitor as part of the air monitoring/sampling program described in the Project's Health and Safety Plan. Soil cuttings will be placed in 55-gallon drums, labeled, and moved to a common drum staging area. The groundwater monitoring wells will be developed at least 24 hours after installation. Development will consist of surging and pumping until the water is relatively sediment free and specific parameters (temperature,pH, and specific conductance) have stabilized. Groundwater samples will be collected from the new monitoring wells approximately 72 hours after the wells have been developed. 2.3.3 Subsurface Logging The Site geologist will log the subsurface conditions encountered in all of the Site borings; recording the information on a Drilling Log Form. Borings shall be logged as follows: Sampling and Analysis Plan 5 of 24 DePaoli Property November 14,2007