GENERAL35449 - Laserfiche WebLink

Home Browse Search

-24- The alluvial bodies are not laterally continuous through the length of the Colorado River, but are dissected by meanderings of the Colorado and by the narrow flood plain of the Colorado River across the Grand Hogback Monocline. The surface facilities of the Coal Ridge No. 1 Mine are east of the outcrop of the Grand Hogback, and on the south side of the Colorado River. The alluvial body present at the confluence of Harvey Gap and the Colorado River is on the north side of the Colorado River and to the west of the Grand Hogback outcrop. Therefore, these two alluvial bodies are not continuous. However, due to the relationship between the waters of the alluvial bodies and the Colorado River, there is a potential that impacts to the alluvium could be cumulative between the mines. Description and hydrologic Impacts of the Coa] Ridge No. Mine The Coal Ridge No. 1 Mine is a proposed operation with no surface or underground disturbance present to date. The Division's review and permitting process for the Coal Ridge No. 1 Mine has not been completed. Therefore, the following conclusions on impacts to the hydrologic balance from the proposed mining Operations at the Coal Ridge No. 1 Mine are based on the information available at present. These projected impacts may change as new information becomes available. This CHIS will be revised to reflect any such changes at the time of publication of a decision for the Coal Ridge No. 1 Mine. The Coal Ridge No. 1 Mine is designed as a hydraulic mining process within the Wheeler coal seam. The hydraulic mining process is a relatively new development within the coal industry, which uses high pressure water to fracture and rubbelize the coal. Entries within the coal seam are designed to move upslope so that gravity allows flow of water from the mining section to the portal. The entire mine is designed as a closed water system enabling reuse of almost all the water within the hydraulic system. The total acreage to be mined during the life of mine is 5,900 acres. The total surface disturbance proposed for the life-of-mine is 256 acres. The surface facilities will be built on unconsolidated sediments, including colluvium, transition zone, and terrace deposits between the Colorado River and the Grand Hogback, and on exposed bedrock to the east and west. Surface runoff from the facilities will be totally contained within sediment ponds except for outslopes of the railroad and access roads. The total disturbance to alluvial material within the surface facilities is proposed as 6.4 acres. The surface facilities in the vicinity of the portal will include the shop and office area with parking. Coal preparation and storage facilities will a]so be present in this area. The mining process will produce both fine and Coarse slurry which will be initially ponded on the colluvial terrace near the portal area. These ponds will be lined to restrict inflow into the colluvial material. A thickener plant wi]1 be needed. This thickener plant will be a concrete structure precluding loss of water into the colluvium. A diversion ditch will be emplaced above the portal area and around the surface facilities to drain all