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T rz <br />Revised (199 Estlmate oP Annual Use and Evaporative <br />Loss oP Surface Waters Discharged EY~om Trapper Mine <br />Evaporative Depletion from Impoundments <br />• Assume annual evaporative loss is 24 inches. <br />• 32 existing small sediment ponds average 0.68 acres <br />surface area at high water mark = 32 •0.68 ac * 2' = 43.52 ac-ft <br />• Coyote Dam ®high water mark = 1 * 12.00 ac * 2' =24.00 ac-ft <br />• Proposed Oak Gulch sediment ponds (T'R~7) = 2 •0.40 ac * 2' = 1.60 ac-ft <br />• Future life-of-mine sediment ponds = 14 •0.68 ac * 2' = 19.04 ac-ft <br />• Existing Stock Ponds (73) ®average .13 ac = 73 * 0.13 ac • 2' = 18.98 ac-ft <br />• Future life-of--mine stock ponds (27) = 27 * 0.13 ac * 2' = 7.02 ac-ft <br />Total = 114.16 ac-ft <br />Depletion Due to Road Waterine <br />Average annual water quantity Total = 76.27 ac-ft <br />used for road watering <br />Total Estimated Depletion <br />Augmentation Due to Deep Wells/Pit Pumpage <br />• Assume 10% of pit water originates from surface runoff. <br />• Average annual Trapper well dewatering <br />• Average annual Trapper pit dewatering = 30.58 * .9 <br />Total augmentation <br />Total Adjusted Depletion due to Mining <br />114.16 ac-ft <br />76.27 ac-ft <br />190.43 ac-ft <br />= 32.52 ac-ft <br />= 27.52 ac-ft <br />60.04 ac-ft <br />190.43 ac-ft <br />- 60.04 ac-ft <br />nn 130.39 ac-ft <br />~1~~~ - -- ----.... . <br />FVLjsb -- --- ~ ~-----. <br />[93-A0002] .~: J i 7 1 0~ r. r r fem. Q 'J C J <br />,-- ~-3o~9s _ . <br />~ -- s 5 b -- - _ _-.:__.:_-:-__: _::._. _ - _. <br />