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Work Plan for Alluvial Groundwater Characterization, Big Elk Mine AdrianBrown ground surface. The surface casing will be painted, and the well ID will be painted or stamped on the casing or will be carved into the concrete monument. Dril[ cuttings which result from auger drilling will be spread and manually contoured at the site. The augers and rig will be decontaminated after each drill hole, using atrailer-mounted pressure washer and potable water. Drilling and Completing 3/4-inch Wells The 3/4-inch monitoring wells will be installed using push technology, according to the Standazd Operating Procedures (SOP) attached. According to geologic logs from monitoring wells installed in the alluvium at the Yoast mine, located to the east of the Big Elk Project azea, the alluvium is typically 40 feet deep and consists of silty clay, silty sand, and silty gravel. The drill rig to be used for-this installation is relatively lightweight (12000 pounds on 6 wheels), and will cause minimal disturbance. The sampling tubes will be pushed to refusal, at the alluvium bedrock contact. Geologic samples will be collected in 4-foot intervals, in 1.75-inch diameter plastic sample tubes. The samples will be logged according to standard geologic nomenclature. Samples will not be retained. The wells will be completed using flush-threaded, 0.75-inch ID, 10-slot PVC, with a natural filter pack. Wells will be screened below the water table, with the top of the screen located not more than 5 feet below the top of the water .table and not less than 10 feet below ground surface, where practical. The bottom of the screen located at the bottom of the borehole. The wells aze generally expected to contain 20-30 feet of screen, and samples will be representative of the entire saturated aquifer thickness. The final decision as to screen placement will be made by the on-site hydrogeologist. The well completion will consist of a natural filter pack, with a surface seal. The surface completion will consist of a 4-inch diameter steel surface casing, with locking aluminum cap. This casing will be set 2.5-3 feet into a concrete montunent, and will extend 2-2.5 feet above ground surface. The surface casing will be painted, and the well ID will be painted or stamped on the casing or will be carved into the concrete monument. Any wells which exhibit artesian or flowing artesian head conditions will be sealed and pressurized to avoid damage by freezing. Wells will be re-pressurized monthly, after routine water level monitoring, during the winter months. No drill cuttings will be generated using this drilling method. The drive rod and rig will be decontaminated after each drill hole, using atrailer-mounted pressure washer and potable water, Well Development Both the 2-inch and 3/4-inch wells will be developed by surging and pumping. The 2-inch wells will be developed using a 2-inch surge block on a 3/8-inch steel rod, followed by pumping with a submersible pump and/or bailing. Development water will be dischazged directly to the ground, at a distance of at least 20 feet from the well head. Project 14630.980223 5