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damage to the hydrologic balance outside of the proposed permit area. This section of the findings document is divided into the following subsections: Description of the Hydrologic Environment; Probable Hydrologic Consequences of the Terror Creek Loadout; and Summary and Findings. A separate Cumulative Hydrologic Impact Study (CHIS) is available for review at the Division. The CHIS, filed at the Division, assesses the projected cumulative hydrologic impacts for all anticipated mining operations in the general area of the Terror Creek Loadout on the North Fork of the Gunnison River Valley. Description of the Hydrologic Environment a. Regional Geology For information regarding the geology of the site, refer back to the section entitled Description of the Environment, Geology. b. Groundwater For information regarding the groundwater of the site, refer back to the section entitled Description of the Environment, Hydrologic Balance. c. Surface Water For information regarding the surface water of the site, refer back to the section entitled Description of the Environment, Hydrologic Balance. 2. Probable Hydrologic Consequences a. Groundwater Effects and Mitigation There is no expected impact to groundwater by the Terror Creek Loadout, due to the lack of occurrence of groundwater within the immediate area to be affected by the operation. The operation is located on colluvial material significantly above the elevation of the North Fork of the Gunnison River. This colluvium appears to be in direct hydrologic communication with the North Fork alluvial aquifer. Only minor amounts of groundwater can be expected above the piezometric surface which coincides with the North Fork. Information presented by the applicant with respect to a privately owned water well south of the permit area indicates that water is not encountered until the river elevation is reached. Operations at the Terror Creek Loadout will not intersect any groundwater within the colluvial material due to limited excavation planned for the permit area. Excavation associated with the loadout pad was completed to approximately 20 feet below ground surface and no groundwater was encountered. No springs or seeps have been identified along the colluvial deposit in the vicinity of the permit area. Because no further surface disturbance is proposed, there is no potential for significant impacts to groundwater quantity in the area. There is a very slight potential for quality of water in the alluvial aquifer immediately downslope from the disturbed area to be degraded as a result of percolation of lower quality water from the coal storage piles and sediment pond. The potential for material damage is considered to be negligible and is further discussed in an upcoming section on Operations on Alluvial Valley Floors. 16