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Following confirmation sampling,the temporary well materials were removed and the borings were reamed to 10-inches in diameter to accommodate permanent well installation. 3.1.3 Monitoring Well Construction-Groundwater monitoring wells were constructed using flush-threaded, 2-inch diameter, Schedule 80 PVC casing. The well screen consists of 0.020-inch wide machine cut slots. A sounding tube consisting of flush-threaded, 1- inch diameter, schedule 80 PVC casing was installed within the same borehole. All well materials, including blank and factory-slotted casing,were virgin, decontaminated and factory sealed. All well materials were covered in plastic or similar protective materials when delivered to the site and remained so until used in construction. All well casing is flush-threaded, including the bottom cap at the base of the wells. No glues or solvents were used to connect the casing. Centralizers were not used on the casing, as allowed by State standards, because the wells were installed inside hollow stem augers. The drillers suspended the casing from the top during construction to ensure that the casing remained straight and centered within the augers. Based on the grain size distribution of the shallow, perched aquifer encountered in past site investigations, inert,washed and graded number 2/12 Monterey sand was used as the filter pack material on wells MW-9A, MW-10A, and MW-11A. Well filter pack sand was placed in the annulus by slowly pouring the sand down the auger flights because water was not present during well construction. The augers were withdrawn during filter pack placement to allow the sand to fill the annular spaced between the auger and borehole wall. The depth to the top of the sand was measured periodically using a decontaminated weight. The volume required to fill the annulus was compared with the volume of filter pack material to ensure that no bridging or belling out of the borehole occurred. The filter pack installation was deemed complete when the sand extended approximately three feet above the top of the screen. Following filter pack sand placement,the filter pack was pre-developed by surging the inside of the well screen to remove voids and alleviate bridging. Additional sand was added when necessary to bring the filter pack up to design depth. An approximately 5-foot minimum thickness granular bentonite seal consisting of medium sized chips was placed over the well filter pack.The bentonite was hydrated after placement pouring potable water down the inside of the hollow stern augers. After the water was poured into the augers, it was allowed to hydrate the bentonite seal for at least 30 minutes prior to placement of the upper cement grout. The remainder of the borehole annulus was sealed with an expansive neat cement grout consisting of Portland Type 1/11 cement and powdered sodium bentonite mixture with a water-to-cement ratio that includes no more than 8 gallons of water per sack of cement and 5 percent bentonite by weight. The grout was placed in the annulus using positive displacement tremie techniques. Well Completion Report ® Page 4 Corral Hollow Sanitary Landfill A S 4 0 c A are s May 3,2012