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-45- in lower Trout Creek are used both for flood irrigation and domestic use. The maximum predicted total dissolved solids concentrations are well below a threshold concentration of 1000 mg/1. The threshold concentration for domestic water use is less distinct. The EPA has suggested a criterion of 250 mg/1 for chlorides and sulfates in domestic water supplies (Quality Criteria for Water, U.S. epq, 1976). The water in lower Trout Creek would be expected to have bicarbonate and sulfate as the dominant anions. Sulfates in the 1000 to 1500 mg/1 frequently have laxative effects, but concentrations as low as 200 to 500 mg/1 may effect some individuals. Total dissolved solids concentrations as high as 696 mg/1 were projected to result from the long-term effects of mining. However, these total concentrations would be considerably less than the total. Water in the range predicted would still be considered "good" in terms of palatability. Affected surface waters in lower Trout Creek would remain suitable for both flood irrigation and domestic use. The projections for the Yampa River near hoyden (Table 4) show effects similar to those identified in the other drainages. However, the Yampa River is the major drainage in the area and is less effected by mining operations than the other drainages considered. Affected water quality in the Yampa River would remain suitable for both flood irrigation and domestic use. To verify the applicant's statement of probable hydrologic consequences, to identify adverse effects to the hydrologic system and to ensure that the operations are conducted to minimize disturbance to the prevailing hydrologic balance, the following stipulation is necessary: Stipulation No. 5 THE APPLICANT SHALL SUBMIT AN ANNUAL HYDROLOGIC MONITORING REPORT FOR THE FOIDEL CREEK MINE. THE MONITORING REPORT SHALL INCLUDE A SUMMARY AND ANALYSIS OF DATA COLLECTED DURING THE YEAR, INCLUDING: 1) WATER USED IN THE MINING OPERATION, 2) MINE WATER DISCHARGES TO RECEIVING STREAMS (QUANTITY AND QUALITY), 3) MINE WATER INFLOWS (ANNUAL MINE INFLOW STUDY), 4) STREAM FLOWS AND QUALITY, 5) IMPACTS TU THE QUALITY AND QUANTITY OF ALLUVIAL AND BEDROCK AQUIFERS, AND 6) IMPACTS TO SPRING FLOWS AND QUALITY. THE MONITORING REPORT SHOULD INCLUDE A DESCRIPTION OF MITIGATIVE MEASURES TAKEN TO MINIMIZE DISTURBANCE TO THE PREVAILING HYDROLOGIC BALANCE. THE MONITURING REPORT SHALL BE ADEQUATE TO PLAN FOR MODIFICATION OF SURFACE OR UNDERGROUND MINING ACTIVITIES, IF NECESSARY, TO MINIMIZE DISTURBANCE TO THE PREVAILING HYDROLOGIC BALANCE. Cumulative Hydrologic Assessment - Summary and Findings A cumulative hydrologic assessment of all anticipated mining on the hydrologic balance in the general area of the Foidel Creek Mine has been made by the Division. This assessment has considered the short-term and the long-term effects of mining to the surface water and ground water hydrologic systems. The surface water assessment was made using results from a U.S. Geological Survey water quality model.