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Mr. Dustin Czapla <br /> Page 4 of 7 <br /> The recirculation/monitoring wells will be completed near the former Pinnacle Mine Dump <br /> (Figure 3). The wells will be constructed in relatively flat areas adjacent to existing access <br /> roads. The 2019 wells are anticipated to be completed in July 2019. To accommodate <br /> drilling and well installation, surface grading will be performed on the Pinnacle Mine Dump <br /> area. The area will be graded to shed snowmelt and stormwater without ponding. <br /> Boreholes which are selected to be completed as wells are anticipated to be at depths of <br /> up to 140 feet. Boreholes which are not completed as wells would be plugged and <br /> abandoned following drilling and sample collection. <br /> Boreholes will be advanced and wells will be constructed in accordance with Colorado <br /> Office of the State Engineer guidelines. Wells will be completed to anticipated depths up <br /> to 140 ft below ground surface and will be constructed with 5-inch schedule 80 PVC 6- <br /> inch casing. Well screens will have a slot size of 0.020 inches and screen lengths will be <br /> up to 50 feet. An 8/12 sized sand filter pack or similar sand will be used as screen filter <br /> packs. The annulus of each well will be sealed using a hydrated bentonite seal above the <br /> screen interval and a cement and bentonite mixture grout from the bentonite to near the <br /> ground surface. The surface stick-up well completion will consist of an 8- to 10-inch steel <br /> vault and locking lid cemented in place with concrete. The production PVC casing will be <br /> sealed with a locking cap. The well vault will be surrounded by an approximate 2-foot <br /> diameter concrete apron sloped to facilitate proper drainage away from the well. <br /> Equipment used for the well installation includes drilling equipment and support vehicles. <br /> Drill cuttings will be handled as described below. <br /> Surface Disturbance <br /> Drilling and Monitoring Well Completion <br /> A total of up to 1.1 acres of previously-disturbed or reclaimed ground within the Pinnacle <br /> Mine Dump will be used during drilling and completion of recirculation/monitoring wells <br /> (Figure 3), which includes grading of the former Pinnacle Mine Dump and placement of <br /> impacted drill cuttings in the Tie Camp disposal cell (Figure 3). The disturbed areas will <br /> be reclaimed once the piezometers/wells are no longer being used as part of reagent <br /> injections and long-term monitoring associated with uranium load reduction system <br /> implementation and/or site characterization, as described below. Boreholes not <br /> completed as wells will be plugged/abandoned and reclaimed after drilling and sampling <br /> has been completed. <br /> Drill cuttings will be screened using a hand-held Geiger-Mueller (GM) meter and <br /> segregated at the surface. Material that exhibits elevated counts per minute (cpm) relative <br /> to local background will be isolated for disposal in the low-grade ore disposal cell adjacent <br /> to Tie Camp drainage (Figure 3).Approval for placement of drill cuttings will be requested <br /> from the RMP, and work will be performed in accordance with the terms of the RML. Drill <br /> cuttings that do not exhibit elevated cpm readings relative to background will be spread <br /> and incorporated into the surface at the drilling locations. <br /> Fencing and Reagent Injection/Recirculation Infrastructure <br /> HOMESTAKE MINING COMPANY O 1 1 2 MARSHALL STREET, SARGENTS, COLORADO 8 1 24B <br />