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Water Consumption. Water removed from the Purgatoire River for use in the mine is dependent upon the mine production rate. Consumptive use rates for the continuous miner and longwall miner are 5.85 and 17.72 gallons per ton of coal. In 1993, approximately 86,979 tons of coal were produced by continuous miners at the Golden Eagle Mine. Thus, 1.61 acre-feet of water were used for continuous miners at the Golden Eagle Mine. Coal production by the longwall method was 856,048 tons; therefore 46.6' acre feet. of water were consumed by longwall mining operations. The sum of water consumed from the North Fork of the Purgatoire during 1993 is calculated at 48.23 acre-feet. All domestic water utilized at thc~ Golden Eagle Mine is supplied by the City of Trinidad. Water usage from the city during 1993 was 3.7 acre-feet. Other consumptive uses include the moisture in the in-situ coal and groundwater inflow 'into the mine workings. Estimated water inflow during 1993 was approximately 208 gallons per minute, or 335.5 acre- feet per year'. Water is extracted from the mine by direct pumping of collected mirie-water~to~the surface; moisture in the coal, gob and waste; and increased humidity in mine ventilation exhaust air.' With regard to surface water balance, discharges back into the Purgatoire system are from mine water discharge and return of treated sanitary sewage water.. The quantity of mine water returned (annual discharge from mine treatment ponds GE002 and GE005 and sewage treatment discharge from GE045) at the Golden Eagle Mine is calculated as 139.7 acre- feet. `(86,979 tons) x (5.85 gal/ton) - (325,851 gal/acft) = 1.6 acre feet.. Z(856,O48 tons) x (17.72 gal/ton) _ (325,851 gal/acf) = 46.6 acre feet. '(208 gal/min) x (1,440 min/day) x (365 days/year) - (325,851 gal/acf) = 335.5 acrefeet/year. .~ .~ 2.05-43 (Revised oa/2~/94)