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Cross Gold Mine <br />December 2024 G-7 <br /> <br /> <br />early and persistent pyrite, copper, zinc, lead, and silver sulfides and gold. A relatively early carbonate- <br />rich phase resulted in common dolomite, calcite, rhodochrosite, and other carbonate minerals in the <br />veins. These carbonates are indicative of the acid-neutralizing potential of the ore body, and therefore <br />the lack of any acid rock drainage potential. The Caribou stock (Cross and Caribou) is primarily <br />monzonite to quartz monzonite. Minor rock types occur as small dikes and include high potassium felsic <br />dikes and magnetite-biotite monzodiorite although there are some differences in rock type (Holland <br />1994). <br />The water quality is best explained by the mineralogy of the ore and the local geology. Because the <br />deposit is generally low in reactive iron sulfides (e.g. pyrite, pyrrhotite, marcasite, chalcopyrite) as <br />compared to other base metal sulfide deposits, the acid generation is low. Acid-neutralizing-minerals <br />are present in sufficient quantities in the calc-alkaline intrusives that ground water is near neutral to <br />slightly basic pH (Knight Piésold, 2004). Ground water becomes surface water in Front Range <br />catchments like Middle Boulder Creek. <br />The general absence of iron staining in oxygenated environments at the Cross Gold Mine facility <br />suggests that there is a limited quantity of reactive iron pyrites to free acid and dissolved iron in the <br />subsurface, and that the dissolved iron and acid that is created is attenuated before it discharges to the <br />surface. This concept is further borne out by several studies noting the lack of general water quality <br />deterioration related to historic mining in Middle Boulder Creek, other than sulfate (SO2-) ions (Murphy <br />et al., 2003. Chpt. 3 & 4). The source of the sulfate increase is attributed to the sulfur in pyrites at mines <br />and ore bodies being oxidized. <br />3. Water Consumption <br />Water will be used at the Cross Mine in both operations and for personnel. <br /> <br />Historically, operations have used three wells to supply water for domestic and potable use. The three <br />wells used for domestic use (Cross, Cabin, and Caribou) have been re-permitted as domestic/industrial <br />with the Division of Water Resources, applications filed May 5, 2021. The well ownership has been <br />changed to Grand Island Resources LLC to align with water rights ownership. Water rights are provided <br />through a 1/8 share in the Farmers Ditch Company adjudicated and decreed for use from mine <br />workings in case number W-8261-76. The water right for the Farmers Ditch Company is included in <br />Appendix G-3. <br /> Operational Water <br />Historically, operations have used a pump located on the 4th level of the Cross Mine for dewatering. The <br />water from within the Cross Mine is then used to operate drills and other equipment underground as <br />needed, which keeps the water within the mine. Currently, with no mill onsite, no water is pumped from <br />the Cross Mine for use in any processing. Once the proposed mill is fully designed and permitted, it will <br />use water from within the Cross Mine. The water source will be permitted via Colorado Division of