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constructed and maintained as permitted. This has been designed to protect all offsite <br />areas from any detrimental impacts from sediment or surface runoff originating on the <br />mine site. <br />It is possible that offsite areas might receive discharge from such sources as <br />underground mine water, refuse pile leachate, or other mine - related activities. Such <br />parameters as iron and oil and grease are strictly regulated by point source discharge <br />permit standards (issued by the Colorado Department of Public Health and <br />Environment). However, mine - related discharge may exhibit increased levels of total <br />dissolved solids. The Bowie No. 2 Mine permit document provides reasonable <br />predictions of mine - related discharge quantity and quality, specifically emphasizing <br />possible increases in total dissolved solids to the hydrologic system. The predictions <br />indicate that any such increases should not be significant, and downstream uses <br />should not be impacted. <br />Perched groundwater, located above the mine workings and within the permit <br />boundary, could be impacted by subsidence. Specifically, subsidence could <br />temporarily de -water these zones; however, these water sources are not used, and <br />recharge should occur over time. It is also possible that the local bedrock <br />groundwater quality could be impacted by elevated total dissolved solids <br />concentrations, as the mine fills with water following mining, and as the water <br />infiltrates to surrounding groundwater. Impacts to the Rollins Sandstone should be <br />minimal, due to the vertical separation from the mine workings. Impacts to the seam <br />to be mined (B -seam) and the sandstone that overlies it are more likely, but are <br />difficult to quantify given a relative shortage of data; this is addressed by PR -14 <br />which is approved with a stipulation, described earlier in this document, that will see <br />the construction of two new monitoring wells in those seams. Local alluvial systems <br />downgradient form the mine should not receive sufficient mine water drainage to <br />create any impacts. <br />IV. Topsoil <br />Information regarding baseline soil studies may be found in Section 2.04.9 of the permit. <br />Information regarding the salvaging and replacement of topsoil may be found in section <br />2.05.4 of the permit. With two approved exceptions, all available topsoil will be salvaged <br />from areas to be disturbed by mining prior to disturbance. During reclamation, topsoil <br />will be replaced in a 12 inch deep layer on facilities areas. Six inches of topsoil will be <br />replaced on top of 3.5 feet of fill over Gob Piles 41, 92, and 94; 1.5 feet of topsoil will be <br />replaced on Gob Pile 93 . <br />A. The Division does not propose to approve alternative procedures for topsoil <br />protection following removal (4.061(2)). <br />B. The Division does not propose to waive the requirement for clearing of vegetation <br />cover prior to topsoil removal (4.06.2(1)). <br />C. The Division is proposing to grant a variance from topsoil removal in accordance <br />with Rule 4.062(2)(a). Topsoil will not be salvaged from areas where topsoil depth <br />is less than three inches, topsoil is extremely rocky, or slopes are steeper than 2:1. <br />Page 36 of 46 <br />