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Mines include impacts to: <br />1. Quantity of flow in the Colorado River, <br />2. Quantities of flow in Rapid and Cottonwood Creeks, <br />3. Surface seeps and springs above the Roadside Mine, <br />4. Dams and reservoirs above the Roadside Mine, and <br />5. Impacts due to water consumption by mine operations. <br />The permittee states that approximately 0.47 cfs of mine discharge water is added to the <br />Colorado River, increasing the flow by an average of 0.01 percent. Most of the water <br />pumped from the Roadside North Portal ultimately comes from the Colorado River by way <br />of aquifers which subcrop below the alluvium of the river. In addition, the water pumped <br />from the Roadside Mine would naturally contribute to base flows in the Colorado River <br />through aquifer dischazges to the river. Therefore, the mining operation should have an <br />insignificant effect on the quantity of water in the surface and groundwater systems of the <br />Colorado River. <br />2. Monitoring of both Cottonwood and Rapid Creek since 1985 has shown minimal <br />disturbance due to subsidence. Both creeks have infrequent flow patterns. Cottonwood <br />Creek, although a major tributary to Rapid Creek, is dry by late summer. Rapid Creek is <br />intermittent in nature. Where surface cracking was observed, within a year the crack was <br />refilled with sediment from the creek channel Minor ponding has also been observed to <br />have taken place in the subsided areas. This ponding was for a relatively short period and <br />has disappeared. Monitoring indicates that little surface flow has been lost due to <br />subsidence in the Rapid Creek Basin. <br />3. Twenty-five springs have been located in the Rapid Creek Basin. All ofthese springs aze <br />outside the subsidence angle of draw. None of the springs overlie present or planned <br />underground mine workings. Mining will not affect the natural springs. <br />4. There aze seven reservoirs in the Rapid Creek Basin, all outside the boundazies of the <br />permit area. The Bureau of Land Management has stated, and the Division agrees, that six <br />will not be affected by coal mining in the area. Cabin Reservoir, which is located outside <br />of the permit area, adjacent to the southeast corner of the South Portals mine plan area, <br />could possibly be impacted by subsidence if future mining were to occur within the <br />immediately adjacent portions of the permit area. However, coal extraction operations <br />were suspended in the South Portals mine area in January, 1997, and operations did not <br />resume. Subsequently, the operator filed notice of permanent cessation of operations, and <br />the South Portals were sealed. Mine workings are separated by over a mile from the <br />reservoir, and no further mining is currently proposed. Consequently, there will be no <br />impact to Cabin Reservoir. <br />In the unlikely event that mining operations should resume, the permittee has committed on <br />page 20-10 ofthe permit application to modify the subsidence control and mitigation plan <br />as necessary, prior to resumption of operations within the South Portals mine area. <br />5. Consumptive use of water at the Roadside Mine consists of domestic water used at the <br />surface facilities and preparation plant, mine water used at the preparation plant, applied to <br />underground roadways, and adsorbed to the coal and refuse, and water from the Highline <br />Permit Revision No. 3 Permit No. C-1981-041 <br />July 30, 2007 Page 29 <br />