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M1 INC. The well screen will be set through the augers and will extend from the total depth of the boring (approximately 10 feet below the water table depth)to approximately 3 feet above the groundwater surface at the time the well is installed. nis will allow sampling near the air/water interface in the completed zones during seasonal fluctuations of groundwater elevations. The annular space of the well will be packed with 9212 sand or its equivalent to a point approximately one foot above'the top of the perforate I casing. A two-foot-thick plug consisting of bentonite pellets or chips will be placed above the and in the well to prevent cement from entering the sand pack and to ensure annular integrity. The remaining annulus will be backfilled with a mixture of neat cement and powdered bentonite (less than 5 percent) to grade or as directed by PHSEHD personnel. i A cast-aluminum utility box with a PVC apron will be placed over the well head and set in concrete, flush to slightly above the surrounding grade. Utility boxes should have a watertight seal to protect against surface-water infiltration. The cover to the box will include countersunk bolts which require a special wrench to remove. The well head will be fitted with a locking well cap to protect against unauthorized disturbance of the well. This design will discourage vandalism and reduce the possibility of accidental di turbance of the well. Exhibit 4 depicts a schematic of the proposed monitoring well completion technique. If hydro punch technique is used to establish vertical and lateral extent of contaminated groundwater, all holes will be logged and sampled ur der the direction of a California Registered Geologist. Temporary monitoring wells may be utili ed to obtain soil and groundwater samples using sampling protocol outlined for the soil borings and monitoring wells above. Logs will be prepared for each soil boring and/or exploratory trench, monitoring well,hydro punch and/or temporary monitoring well and will depict the lithologies penetrated, analytical sample locations, OVM readings, and any descripttoj is of contamination encountered. The logs will include a description of drilling methods and sampling techniques. All geological work will 08420010.001 9