2007-11-16_REVISION - C1981041 (6)

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This fact is important in defining the hydrologic impact on the water-bearing strata by the mine operation (see the Probable Hydrologic Consequences section of this document, Section C.II.). There are four primary water bearing zones that may be directly or indirectly affected by the mine operation: the Colorado River alluvium, the undifferentiated sandstone lenses in the Mesaverde above the coal seam, the Cameo coal seam, and the Rollins sandstone unit below the coal seam. There are no aquifers in the permit or adjacent area that can store and transmit water of sufficient quality or quantity for beneficial use. A September, 1997, study included in the permit application package confirms that the Rollins Sandstone in the permit area does not meet the regulatory criteria of an aquifer. Laboratory analyses have shown groundwater in the permit vicinity to be high in salts and of poor quality. Therefore, no beneficial uses of groundwater exist in the permit or adjacent area. No groundwater rights have been adjudicated on or adjacent to the permit area to date. Only one groundwater well (an alluvial well) exists adjacent to the permit area; it is used for stock watering. Please refer to Section C.II.I. (Probable Hydrologic Consequences) for further hydrologic information, including the groundwater monitoring plan. Additional information on hydrology can be found in Tabs 7, 17 and 18, of the permit and Section C.II. of this document. Surface Water Hydrology A general description of the surface water hydrology of the permit area is found in Volume 2, Tab 7 of the permit application. Maps displaying the general surface water hydrology are found in Exhibits l and 17 of that document. Please see Section C.II. of this document for a discussion of the Probable Hydrologic Consequences (PHC) of the Roadside Portal Mines on surface water quantity and quality and for a further discussion of the surface water monitoring plan. Alluvial valley floors (AVF's) are discussed in Section C.XI. of this document. The Colorado River is the only perennial stream in the permit area. On the west side of the river, Coal Creek and Jerry Creek flow through the Roadside North Portal portion of the permit area within deeply incised canyons draining approximately 12 and 70 square miles, respectively. Coal Creek, an ephemeral drainage, passes through surface mine disturbance near the Roadside North Portal where the channel has been diverted. Jerry Creek is an intermittent drainage located in the extreme northern portion ofthe permit area. In addition, a small portion of the permit area drains to Asbury Creek, which enters the Colorado River from the northwest, to the east of Jerry Creek. Flows in all of these drainages occur primarily during spring snowmelt and in response to sudden, high intensity thunderstorms, the latter of which are characterized by high peak discharges, short flow durations and high sediment loads. On the east side of the river, the Roadside Mine will undermine two additional canyons: Rapid Creek and Cottonwood Creek. Both creeks are intermittent during most years, but do flow continuously during wet years. Flows in these creeks occur primarily in response to annual snowmelt and seasonal precipitation events. Intake structures are present in both Rapid Creek and Cottonwood Creek to divert water from those drainages into reservoirs for later release which, along with water from other storage structures, can artificially increase the duration of stream flows. Several small unnamed drainages (washes) on the east side of the river will also be impacted by mining, either through surface disturbance or through undermining. The only other major surface water body within the permit area is the federally owned Highline Canal. This canal carries river water down the west side of DeBeque Canyon of the Colorado River, with siphons under the channels of Coal and Jerry Creeks. The Highline Canal is primarily used for agricultural purposes in the Grand Valley. Permit Renewal No. 5 10 November 16, 2007