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7. Conformance with State, regional, and/or local land use plans, programs, and policies: There are no State, regional, and/or local land use plans, programs, and policies affected by the proposal. B. Other Affected Resources It is likely that subsidence will occur in the proposed mining plan modification area should this proposal be approved. The mining area is located in steep, hilly terrain, and is situated north of the Purgatoire River. The plastic form of subsidence should occur as the result of longwall mining activities and will likely be area-wide in extent. The surface depressions will be shallow and barely noticeable, due to the rolling topography and the 450 to 900 foot depth of the coal seam below the surface elevation. Disapproval of the mining plan modification would have no impact on environmental conditions now present in the mining plan area. C. Cumulative Impacts The Golden Eagle mine is located adjacent to the New Elk, which is also an underground mine. Because of their proximity to • each other,it is expected that the mines will have a cumulative hydrologic impact on surface and ground water systems. Possible combined impacts include dewatering the coal seam and overburden aquifers, and the deterioration of the quality of ground water flowing through the abandoned coal workings into coal aquifers. The Allen seam (New Elk Mine) and the Maxwell seam (Golden Eagle Mine) are separated by 20 feet of interburden. It is likely that subsidence will cause a breakdown of this strata during or at the conclusion of mining activities. Should this event occur, hydrologic communication will take place between the two coal seams, and ground water impacts are expected to be accumulative. During operations, dewatering would occur in the coal aquifer and the drawdown of the piezometric surface could extend laterally a distance of approximately 3 miles from each mine. After-~the cessation of mining operations, mine water would no longer ba:~dscharged and the abandoned workings would fill with water. The ground water level and the piezometric surface would partially recover. Approximately twice as much ground water would flow through the flooded mine workings than flowed through the undisturbed coal surrounding the mine workings. Ground water would stagnate in the mine workings and react with coal and coal refuse, and other materials in the mine cavity. This ground water would have a poorer quality than the water currently pumped from the mine. The effect of having two mining operations affecting strata in hydrologic communication with one another would be to decrease 12