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Exhibit G Water Information <br /> 1 . Groundwater Resources <br /> Operations are not expected to disturb groundwater resources. Excavation and cleanup of the waste <br /> piles will not involve excavating below the natural ground level and as such no groundwater will be <br /> encountered. Neighboring wells have been mapped on Map C-1 for reference. <br /> 1.1 . Known Aquifers <br /> The groundwater system near the London Mine area of Alma, Colorado consists of multiple <br /> interconnected aquifer units. Quaternary glacial deposits and alluvium form the uppermost unconfined <br /> aquifer, which overlies a more complex bedrock aquifer system. The bedrock aquifers include the karst- <br /> developed Leadville Limestone Formation, which functions as a confined aquifer, as well as water- <br /> bearing fractures in Precambrian crystalline rocks and younger Tertiary intrusive bodies. <br /> The area's extensive mining history has significantly altered the natural groundwater flow patterns. <br /> Mine workings create artificial conduits that can connect different aquifer units and establish preferential <br /> flow paths through the subsurface. Groundwater recharge occurs primarily through snowmelt from the <br /> surrounding mountainous terrain, along with direct precipitation and losses from local stream systems. <br /> 2. Surface Water Resources <br /> Surface water in Mosquito Gulch consists mostly of snowmelt from the mountain slopes and the runoff <br /> from mountain rainfall. The continental divide runs along the east and north side of the gulch. No rivers <br /> or major streams pass through the permit area. <br /> Waste pile excavation and cleanup will remove potentially acid-forming material from the gulch and <br /> lead to long term surface water quality improvement. The exact location and number of waste piles <br /> being cleaned up is dependent on a variety of factors. Therefore, the surface water hydrology for this <br /> operation has been organized into standardized basins. An evaluation of the likely waste pile targets of <br /> this operation has shown that none will have a drainage area greater than 50 acres' due to the high <br /> altitude of the waste piles. Unlikely operations at lower altitudes, all of the waste piles are fairly close to <br /> the top of mountains that act as the top of drainage basins. Appendix G-1 lists the hydrologic <br /> calculations of the 10-YR, 24-HR event for each of the standardized drainage basins. The standard <br /> basins are: <br /> • 5-acre • 30-acre <br /> • 10-acre • 40-acre <br /> • 20-acre • 50-acre <br /> 1 The overall drainage basin area includes the waste pile itself and undisturbed ground that drains to a waste pile. <br /> It is not related to the 20-acre disturbance limit. <br /> London Mountain Clean Up <br /> April 2025 G-1 Lewicki&Associates <br />