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The Eagle No. 5 Mine is impacting the quantity of ground water in the Middle sandstone. Figures III-17a through III-17c, in the application, contain hydrographs of ground water levels for the Middle sandstone over time. These hydrographs show steady declines in ground water levels for the period from July, 1981 to April, 1983. The rate of ground water level decline is as much as 33 feet per year (in well 81-01). The applicant acknowledges, on page III-42, that these declines are probably related to drainage of the Middle sandstone to the underground mine workings. These declines in Middle sandstone water levels will not impact any water wells (ground water use), since presently there are no ground water wells completed in this aquifer. The Eagle No. 5 Mine may be depleting the quantity of water in the Yampa and Williams Fork stream/alluvial systems. These depletions could result from diverting surface flows through the subcrop areas of the "F" coal seam and the Middle sandstone beneath the rivers through these aquifers and into the mine workings. The company has projected the current stream depletions by the Eagle No. 5 Mine using the equation developed by McWhorter (1981). The company has projected that the current rate of stream depletion may equal 180 gpm or 0.4 cfs. This rate would be 2X of the 7-day, 10-year low flow (27.8 cfs) (pages III-77a and 78 revised 10/24/83). These projected stream flow depletions are not expected to increase during the remainder of the 5-year permit period.. Monitoring data provided by the applicant shows that the Eagle No. 9 Mine is impacting the quantity of ground water in the first White sandstone. Figures III-17e through III-17g, in the application, contain hydrographs for this sandstone aquifer. In these hydrographs, the first White sandstone has shown ground water level declines of approximately 25 ft/yr in well 81-03, of 8 ft/yr in well 61-04a, and no decline in well 81-19. Ground water levels show higher rates of decline in wells closer to the Eagle No. 9 Mine workings. Page TII-50 of the permit application acknowledges that the mine workings have caused some drainage of this aquifer. Empire Energy Corporation has modeled the drawdown cone (decline in the ground water levels) in the White sandstone over the 5-year permit period (pages III-76 to III-77 revised 70-24-83). The predicted drawdown in the 3 White sandstones at one mile from the center of the mine is 130 feet, at 2 miles is 40 feet, at 3 miles is 15 feet, and at 4 miles is less than 5 feet. Empire Energy Corporation has identified one water supply well completed within the White Sandstones. This well is owned by Francis Lux and is located about one mile from the center of the mine. The company has predicted that drawdowns caused by the mine in the well one mile from the center of mine may reach 130 feet. This would indicate that the Eagle No. 9 Mine may adversely affect the Lux water supply well. If this well is adversely affected (e.g., no longer provides a dependable water supply), the company has committed to drilling a replacement water supply well (page III-77, revised 10/24/83).