2007-11-16_GENERAL DOCUMENTS - C1981041 (3)

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2. Monitoring of both Cottonwood and Rapid Creek since 1985 has shown minimal disturbance due to subsidence. Both creeks have infrequent flow patterns. Cottonwood Creek, although a major tributary to Rapid Creek, is dry by late summer. Rapid Creek is intermittent in nature. Where surface cracking was observed, within a year the crack was refilled with sediment from the creek channel. Minor ponding has also been observed to have taken place in the subsided areas. This ponding was for a relatively short period and has disappeared. Monitoring indicates that little surface flow has been lost due to subsidence in the Rapid Creek Basin. Twenty-five springs have been located in the Rapid Creek Basin. All of these springs are outside the subsidence angle of draw. None of the springs overlie present or planned underground mine workings. Mining will not affect the natural springs. 4. There are seven reservoirs in the Rapid Creek Basin, all outside the boundaries of the permit area. The Bureau of Land Management has stated, and the Division agrees, that six will not be affected by coal mining in the area. Cabin Reservoir, which is located outside of the permit area, adjacent to the southeast corner of the South Portals mine plan area, could possibly be impacted by subsidence if future mining were to occur within the immediately adjacent portions of the permit area. However, coal extraction operations were suspended in the South Portals mine area in January, 1997, and operations did not resume. Subsequently, the operator filed notice of permanent cessation of operations, and the South Portals were sealed. Mine workings are separated by over a mile from the reservoir, and no further mining is currently proposed. Consequently, there will be no impact to Cabin Reservoir. In the unlikely event that mining operations should resume, the permittee has committed on page 20-10 of the permit application to modify the subsidence control and mitigation plan as necessary, prior to resumption of operations within the South Portals mine area. Consumptive use of water at the Roadside Mine consists of domestic water used at the surface facilities and preparation plant, mine water used at the preparation plant, applied to underground roadways, and adsorbed to the coal and refuse, and water from the Highline Canal used for dust suppression on surface roads. Quantities of water consumed at the mine are reported annually in the Annual Hydrologic Report. Quantities consumed during active operations in water year 1992 were as follows: Gallons Used Location Used Domestic Water 1,397,000 Surface Facilities 2,150,000 Preparation Plant Mine Water Highline Canal 3,350,000 Mining 3,150,000 Preparation Plant 750,000 Underground Roads 1,170,000 Surface Roads Permit Renewal No. 5 30 November 16, 2007