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minimal and surface cracks should fill with sediment relatively quickly. Actual interruption of surface flows should not be significant. Stock ponds located above the mine, and within the permit azea, could also be impacted by subsidence; however, significant impacts are unlikely, due to the approved subsidence protection plan for the Bowie No. 2 Mine which should minimize subsidence beneath any of the stock ponds. These stock ponds aze owned by BRL. The required sediment and drainage control plan for the Bowie No. 2 Mine must be constructed and maintained as permitted. This system will protect all offsite azeas from any detrimental impacts from sediment or surface runoff originating on the mine site. It is possible that offsite azeas might receive dischazge from such sources as underground mine water, refuse pile leachate, or other mine-related activities. Such pazameters as iron and oil and grease aze strictly regulated by point source discharge permit standazds (issued by the Colorado Department of Public Health and Environment) limitations. However, mine-related discharge may exhibit increased levels of total dissolved solids. The Bowie No. 2 Mine permit document provides reasonable predictions of mine-related dischazge quantity and quality, specifically emphasizing possible increases in total dissolved solids to the hydrologic system. The predictions indicate that any such increases should no[ be significant, and downstream uses should not be impacted. Perched groundwater, located above the mine workings and within the permit boundary, could be impacted by subsidence. Specifically, subsidence could temporarily de-water these zones; however, these water sources aze not used, and recharge should occur over time. It is also possible that the local bedrock groundwater quality could be impacted by elevated total dissolved solids concentrations, as the mine fills with water following mining, and as the water infiltrates to surrounding groundwater. Impacts within the permit azea should be minimal, due to the relative lack of useable groundwater, and due to the vertical sepazation which exists between the D-2 coal seam, the B-2 coal seam and the Rollins Sandstone located considerably below the mining elevation. Local alluvial systems downgradient form the mine should not receive sufficient mine water drainage to create any impacts. IV. Topsoil Information regazding baseline soil studies may be found in Section 2.04.9 of the permit. Information regazding the salvaging and replacement of topsoil may be found in section 2.05.4 of the permit. Except for one situation, all available topsoil will be salvaged from azeas to be disturbed by mining prior to disturbance. During reclamation, topsoil will be replaced in a 12 inch deep layer. Six inches of topsoil will be replaced on top of 3.5 feet of fill over the reclaimed gob pile. 30