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Cross Gold Mine <br />December 2024 U-7 <br /> <br /> <br />4. Dispose of excavated tailings and extraneous natural material in mill paste mix area or <br />approved offsite disposal facility. <br />5. If tailings deposition is not fresh and has established vegetation, take at least one grab sample <br />of material and conduct SPLP and ABA analysis. More grab samples may be needed <br />depending on the off-site tailings’ extent. Provide sampling results to Division. <br />a. If material is inert according to SPLP and ABA values and the Division concurs, leave <br />the off-site tailings material in place. Place six-inches of topsoil over tailings and seed <br />with reclamation seed mix. <br />b. If material is not inert according to SPLP and ABA values and the Division concurs, <br />remove the tailings material in the same manner as if it were fresh material (step 3). <br />6. Document the extent of the recovery effort with GPS and photographs and report the results to <br />the Division. <br /> <br />Containment of materials occurs throughout the milling process. Ore bays and bins [1,2, & 7] contain all <br />ore materials as they pass through crushing processes along with all dust control water used during <br />crushing. Failure of either ore bin would lead to fracture ore material falling onto the floor of the mill at <br />angle of repose and being contained within the mill building. Ore slurry is generated at the end of the <br />grinding stage as part of the outflow to the flotation cells. In the event of grinding circuit failure, said <br />wettened ore would fall to the mill floor. Similarly, any failure of the flotation cells or associated pumping <br />infrastructure would lead to ore slurry being discharged to the mill floor. Tailings and concentrate <br />slurries produced from thickeners would also be discharged to the mill floor in the event of the failure of <br />tanks, pipes, pumps, or other slurry transport systems. The mill building will be constructed with a <br />minimum 18-inch sealed lip around its perimeter. All access points will ramp down to the internal mill <br />floor to prevent discharge routes. The current mill concept calls for a structure roughly 220’ x 50’. With <br />an 18-inch containment lip, this is a volume of 16,500 CF or roughly 123,000 gallons of storage volume. <br />At a milling rate of 100 tons per day and an assumed specific gravity of 2.6 for hard igneous rock, the <br />total daily volume of ore will be roughly 1200 CF. Assuming an overall solids-water ratio of roughly <br />30:70, the total slurry volume for one day of milling would be 4000 CF, or less than 1/4th the volume <br />capacity of the mill. <br />The mill will drain to an internal clean up sump [18]. <br />5. Non-Fuel Chemicals Stored on Site <br />Upon development of the final mill design a complete list of designated chemicals stored onsite will be <br />submitted to CDRMS as part of the mill design revision. All reagents used in milling will be stored within <br />the designated storage areas, as outlined on Maps C-2B and C-3. These storage areas will be lined <br />and contained to ensure no designated chemicals can discharge from said storage areas.