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19 June 2008 <br /> AGE-NC-02-0950 <br /> Page 3 of 5 <br /> was visually classified on a boring log in accordance with the Unified Soil Classification System; <br /> the soil boring logs are provided in Appendix C. <br /> 3.1.3. Monitoring Well Completion <br /> Pilot borings for wells MW-6 and MW-7 were completed as ground water monitoring wells screened <br /> from 10 to 30 feet bsg utilizing 2-inch diameter schedule 40 polyvinylchloride (PVC) 0.020-inch <br /> slotted well screen and blank well casing.After installing the well casing in each pilot boring,a filter <br /> pack material consisting of pre-washed#2/12 sand was added through the augers from total depth <br /> to approximately two feet above the screened interval. Following placement of the filter pack, the <br /> well was surged to assist in settling the filter pack. <br /> A two-foot bentonite transition seal was placed above the filter pack to minimize the potential for <br /> grout penetration into the screened section of the well. The bentonite seal was formed by pouring <br /> bentonite chips into the annulus and allowing them to settle on the filter pack. The bentonite chips <br /> were allowed to hydrate for a minimum of 30 minutes prior to grouting. The well°was then grouted <br /> to near-surface with portland cement,and a water-tight,traffic-rated well box was installed over the <br /> well. <br /> As-built well diagrams for monitoring wells MW-6 through MW-7 are depicted on the boring logs <br /> in Appendix C. <br /> 3.2. WELL DEVELOPMENT <br /> On 25 March 2008,monitoring wells MW-6 and MW-7 were developed using a steel bailer and an <br /> inertial pump with 5/8-inch polyethylene tubing. Prior to development,the depth to ground water in <br /> wells MW-6 and MW-7 were measured from the top of the well casing to the nearest 0.01-foot <br /> utilizing a Solinst water level meter.Afterwards,ground water was purged from the monitoring well <br /> until the water was visually sediment free; approximately 50 gallons of water were removed from <br /> the wells MW-6 and MW-7. Ground water temperature, pH, and conductivity were measured at <br /> regular intervals during purging using an Oakton water analyzer. The field data sheet for the <br /> development of wells MW-6 through MW-7 are included as Appendix D. h <br /> Purged ground water from MW-6 and MW-7 was temporarily containerized in properly labeled <br /> DOT-approved model 17H 55-gallon drums and stored on-site pending proper disposal. <br /> Advanced GeoEnvironmental,Inc. <br /> k <br />