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these seams are mined, the coal seam aquifer is dewatered . New <br /> areas of the mine have a higher inflow rate than older, developed <br /> ones , which dry out after the area has been developed. Additional <br /> water originates from the Mesaverde sandstone lenses as they are <br /> dewatered by mining activity combined with subsidence . <br /> The operator has committed to a mitigation contingency plan for <br /> downstream users should they be effected by subsidence. <br /> Ground Water Quantity: Effect on the Colorado River Alluvial Aquifer <br /> Water quantity in the alluvium of the Colorado River aquifer is <br /> minimally effected by the mine operations . The quantity of surface <br /> water and groundwater in the Roadside and Cameo facility areas and <br /> adjacent areas will not be adversely affected due to the recycling <br /> nature of the ground and surface waters in the alluvial valley <br /> floor. Since the mines are on the Colorado River alluvial valley <br /> floor , the water pumped from the mines ' old workings is essentially <br /> the alluvial water already present in the river system. Additional <br /> water is added from the draining of the coal aquifer as virgin coal <br /> seams are mined to the south. Both waters are circulated through <br /> the mine workings , thus accumulating solids and salts , before being <br /> discharged into the Colorado River. Approximately 0.7 cfs of mine <br /> discharge water is removed from the underground mine workings and <br /> allowed sufficient time to settle out the solids before being <br /> discharged into the Colorado River . The salts cannot be filtered <br /> out using this method. The salt loading result is discussed more <br /> thoroughly in the section on water quality. <br /> III . Topsoil <br /> Soils resource information found in Volumes I and VI , and the topsoil <br /> salvage and redistribution plan in Volumes I and V of the application <br /> have been reviewed for compliance by the Division. The Division has <br /> also reviewed topsoil information for Cameo Refuse Disposal Areas <br /> Nos . 2 and 3 permit revision. This information can be found in <br /> Section 2 .04.9 , 2.05. 3(5) , 2 .05.4(2)(d) and Appendix XX of the permit <br /> revision application. <br /> Since mining at this operation began prior to the Surface Mining <br /> Control and Reclamation Act, no topsoil was salvaged in construction of <br /> the mine benches . Topsoil from the loadout area was used to build the <br /> loadout stacker pad , although a small amount was stockpiled . The <br /> majority of the topsoil salvaged was removed from the location of the <br /> Cameo refuse piles . <br /> Soils in the general area are commonly high in sodium and occasionally <br /> saline. This is reflected in the sparse vegetation which is primarily <br /> composed of salt-tolerant species and species such as greasewood , which <br /> are commonly found growing in sodic soils . The analyses of the <br /> stockpiled soil and the material presently on the surface of the <br /> disturbed areas reflect the saline and sodic conditions of the <br /> surrounding area. <br /> -29- <br />