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Section 2 Groundwater Monitoring Well Installation Transition Seal—Two feet of bentonite chips or pellets will be placed on top of the filter pack providing a transitional seal from the filter pack to the sanitary surface seal. Surface Seal—All attempts will be made to place a neat cement or cement grout sanitary seal from the ground surface to a minimum depth of 20-feet bgs and extending to the top of the bentonite transition seal. Figures 6 and 7 depict the typical monitoring well completion details anticipated for the site. Additionally, special attention shall be given to the construction of the monitoring wells to minimize the potential for contamination of any materials used in the installation. 2.6 WELL DEVELOPMENT The drilling contractor will develop the wells using a combination of methods. Where practicable and where formations stability permits,well development by gently swabbing the well with a surge block will be initiated before the installation of the bentonite transitional seal or neat cement/cement grout sanitary seal to ensure settling of the filter pack prior to sealing the annulus. Once the seal has been installed and sets up for no less than 12 hours, further development by vigorously swabbing the well with a surge block and manual bailing will ensue and continue until the concentration of suspended solids in the water bailed from the well is sufficiently low to permit pumping with a portable submersible pump. Accumulated fill shall be removed from the bottom of the well screen. Development will continue until the discharge water runs clear and/or field measured turbidity is 5 n.t.u., or less. During the pumping phase of well development,the pump will be moved up and down the entire length of well screen, maximizing the removal of accumulated fines. Water generated from the well during development will be discharged directly to land. 2.7 WELL DISINFECTION It has been ECO:LOGIC's experience that the effectiveness of well disinfection procedures vary. As such, the proposed monitoring wells will not be disinfected unless monitoring results indicate persistently elevated densities of coliform organisms present over three consecutive quarters of groundwater monitoring. Recommendations for subsequent disinfection procedures will be presented within the wastewater facility's quarterly or annual groundwater monitoring report(s), should coliform densities fail to decline over that period. March 2006 Lockeford CSD 2.4 Groundwater Monitoring Well Installation Workplan