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ii. Mine water use. Water used for dust suppression in the mine and on the coal can be counted as 2% of production tonnage. Based upon an annual production of 600,000 tpy, approximately nine acre-feet per year is lost as added moisture on the coal or evaporation from the mine workings. Miscellaneous Water Uses. Miscellaneous water uses include water used on surface roads for dust suppression, drinking water, equipment wash water and shower water. Many of these uses have return flows via the waste water treatment plant. From all miscellaneous water uses, the total is approxiamtely 1s acre-feet per year. Of the 13 acre-feet, 5.4 acre-feet are returned to the river as treated effluent leaving a net loss of 7.6 acre-feet. Return Flows. Return flows to the North Fork of the Gunnison River are attributed to discharges of treated mine water and precipitation runoff. The average total discharges from all the ponds is approximately 40.4 acre-feet per year. Net Water Increase Total water withdrawn from the North Fork of the Gunnison River or lost through evaporation equals 36.0 acre-feet per year. Return flows to the North Fork of the Gunnison River equal 40.4 acre-feet. The difference between water withdrawn from the river and evaporated from the surface of the sedimentation ponds and that which is returned to the river may be attributed to mine water and increased runoff from impervious surface areas within the mine surface facilities area.