2022-11-07_REVISION - C1981041 (2)

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this concern. The study concluded that a portion of the total outflow from the mine could be attributed to a reduction of the available surface flow in discrete segments of Rapid and Cottonwood Creeks. The initial study concluded that the effect of the mine on groundwater flow may be reducing the available surface flow in those segments of Rapid and Cottonwood Creeks by approximately 38 GPM, based on an average measured discharge of 118 GPM from the mine outfall. SCC entered into a Compliance Order on Consent("Consent Order") with DWR on January 13, 2022 to implement and adjudicate a plan for augmentation with the Water Court in and for Water Division 5 to remedy any water rights injury attributable to the reduced flow in Rapid and Cottonwood Creeks induced by the Roadside South Portal Mine. Groundwater Quantity: Effect on the Colorado River Alluvial Aquifer Water quantity in the alluvium of the Colorado River aquifer is minimally affected by the mine operations. The quantity of surface water and groundwater in the Roadside North and South Portal facility areas and adjacent areas will not be adversely affected due to the recycling nature of the ground and surface waters in the alluvial valley floor. Mining did not occur beneath the Colorado River alluvial valley floor. Groundwater inflows to the South Mine workings discharge by gravity flow through a dewatering pipe near the reclaimed North Decline, at Discharge Site 016, into the Colorado River. Approximately 0.7 cfs of mine water is discharged into the Colorado River. IV. Topsoil Soils resource information found in Volume 2, Tab 9, and the topsoil salvage and redistribution plan in Volumes 3 and 5, Tabs 13 and 14, of the application have been reviewed for compliance by the Division. Since mining at this operation began prior to the Surface Mining Control and Reclamation Act, no topsoil was salvaged in construction of the mine benches. Topsoil from the loadout area was used to build the loadout stacker pad, although a small amount was stockpiled. The majority of the topsoil salvaged was removed from the location of the Cameo refuse piles. Soils in the general area are commonly high in sodium and occasionally saline. This is reflected in the sparse vegetation which is primarily composed of salt-tolerant species and species such as greasewood,which are commonly found growing in sodic soils. The analyses of the stockpiled soil and the material presently on the surface of the disturbed areas reflect the saline and sodic conditions of the surrounding area. Upon completion of backfilling and grading operations, topsoil will be redistributed to a minimum depth of six inches,with the exception of specified areas where topsoil was not salvaged originally. These areas will be covered with a suitable amount of plant growth material and amended as necessary. Prior to redistribution of the topsoil, the graded surface will be ripped to relieve compaction and limit surface slippage. 37