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Ms. Katie Todt <br /> February 9, 2026 <br /> Page 4 of 9 <br /> Grizzly overflow pile: 706 ft2 x (40"/yr evap - 6.73" eff. ppt)(1 ft/12") = 0.04 AF <br /> Trommel: 64 ft2 x (40"/yr evap - 6.73" eff. ppt)(1 ft/12") x (7/24 hrs) x 2 = 0.002 AF <br /> Trommel overflow pile: 706 ft2 x (40"/yr evap - 6.73" eff. ppt)(1 ft/12") = 0.04 AF <br /> Sluice: 160 ft2 x (40"/yr evap - 6.73" eff. ppt)(1 ft/12") x (7/24 hrs) x 2 = 0.006 AF <br /> First Fill Inflow: 0.2 ac x 17 ft depth x (1 - 0.3) x 2 sites = 4.8 AF <br /> Gravel Export: [(150000 tons)(2000 lbs/ton) x 4% water] : 62.4 lb/ft3 x 1 ac/43560 ft2 = 4.4 AF <br /> TOTAL = 36.48 AF <br /> Estimated depletions for the trommel and sluice were increased by a safety factor of 2 to <br /> account for turbulence and ensure a conservative estimate. Total processing depletions were <br /> doubled to account for two processing areas. Depletions resulting from evaporation of <br /> exposed groundwater may be reduced for ice-covered periods. For the purposes of this SWSP, <br /> the Applicant shall replace the evaporation depletions from exposed groundwater any time <br /> the exposed groundwater is not completely covered by ice. <br /> A Glover analysis was performed with the following parameters to determine lagged <br /> depletions: <br /> Transmissivity: 119,276 gpd/ft <br /> Specific Yield: 0.24 <br /> Distance to River: 830 feet <br /> Distance to aquifer boundary: 3930 feet <br /> Monthly lagged groundwater depletions were calculated using the Alluvial Water Accounting <br /> System ("AWAS") developed by the Integrated Decision Support ("IDS") Group at Colorado <br /> State University. Aquifer dimensions and distance to the stream were measured using Google <br /> Earth imagery. Previous placer mining has severely modified the area, resulting in difficulties <br /> identifying surface water pathways; however, the Applicant and DWR's Hydrogeology staff <br /> agreed that an orthogonal line from the well (exposed groundwater surface) to the aquifer <br />