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-38- gpm for the Maxwell Mine. The combined predicted depletion of the stream/alluvial system is 7.3 gpm (0.016 cfs) which amounts to approximately 0.3% of the low flow in the Purgatoire River (5 cfs). This minor loss in stream flow would be offset during mining by the discharge of mine waters from the underground workings. The current average discharge is 123 gpm from the Allen Mine, and 30 gpm from the Maxwell Mine. Each mine is predicted to discharge 180 gpm at full development for a total discharge of 360 gpm (.8 cfs). During operations, water quality in the stream/alluvial aquifer system would be affected by the discharge of water from the underground workings and by seepage from existing and proposed coal refuse piles. At the Allen Mine site, existing and proposed coal refuse piles and mine water discharge add approximately 48 mg/1 to the total dissolved solids concentration during low flow conditions in the Middle Fork of the Purgatoire. This would add approximately 29 mg/1 during the low flow in the vicinity of the Maxwell Mine due to dilution by the North Fork. Mine water discharge at the Maxwell Mine would add another 47 mg/1 to low flow total dissolved solids concentrations in the Purgatoire. The cumulative effect of the mine discharges and the Allen refuse pile is to increase the total dissolved solids concentrations by 76 mg/1 in the Purgatoire River at Maxwell under low flow conditions. Added to baseline concentrations of 300 mg/1 or less this increase would not limit the use of water for either flood irrigation, livestock watering, domestic or municipal uses downstream. Following mining, mine water would no longer be discharged to the river. Only seepage from the coal refuse piles would continue to effect water quality in the stream-alluvial aquifer system. Continued seepage from the Allen waste piles would add approximately 16 mg/1 to total dissolved solids concentrations in the Purgatoire River under low flow conditions. This increase would not be expected to limit water use. Since .t he applicant's baseline data is deficient in estimating recharge, water movement, discharge of ground water and the presence or absence of alluvial aquifers in the tributary drainages in the two mines' permit and adjacent areas, it is not possible to determine fully what the cumulative hydrologic impact would be upon surface and alluvial ground water resources in the general area. A. Required Findings The Division is unable, at the present time, to find that all of the proposed operations have been designed to prevent material damage to the hydrologic balance outside the permit area. The applicant has provided an analysis of the effects of discharge of mine water from Allen Mine workings. This analysis indicates that although water quality would be affected, the affect would not limit water use. The applicant has also provided sufficient information and analysis to demonstrate that the proposed mining operations beneath the Stonewall Valley would not cause a significant loss of flow in the Purgatoire River stream-alluvial aquifer system. The mining in the Allen Mine beneath the Stonewall Valley was determined to not cause material damage to the hydrologic balance outside of the permit area.