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Surface water The Elk Creek lease area is bounded by Hubbard Creek, a perennial stream to the west, and Elk Creek, an ephemeral stream to the east. The lease area is bisected by Bear Creek, an ephemeral stream located near the center of the ]ease. Further to the south (approximately 1 mile) lies the North Fork of the Gunnison River. The surface hydrologic environment ofthe lease area is a direct reflection of site topography, semi-arid climate, and site geology. Tributary drainages in the area are relatively steep and deeply incised. Because the area is relatively dry, most of the precipitation which does occur infiltrates quickly into the relatively coarse unconsolidated surface materials and is rapidly lost to evaporation and transpiration. Very little runoff occurs except during spring snowmelt and major thunderstorm events. What little runoff does occur results in brief, high flow velocities in the steep drainages due to steep terrain. These high flow velocities are often accompanied by relatively high sediment loads and high TSS levels. The steep valley sideslopes and exposures of rocky cliffs along with mass wasting features noted in the previous groundwater section, contribute to significant deposits of large, blocky colluvial materials in the lower valley slopes and most drainage areas. Because of the ephemeral nature of the watersheds within the Elk Creek lease area, there are no significant surface water bodies located within the Elk Creek lease area. Likewise, because of the limited surface water resources in the azea, the Colorado Division of Water Resources (CDWR) water rights data base for the lease area did not include any decreed water rights or non jurisdictional structures located within the Elk Creek lease azea. Subsidence Related Effects With more than 90% of the proposed Elk Creek lease mining area under at least 1000 feet or greater overburden, little, if any, effect from subsidence is anticipated. These zones would be considered minor or low potential for subsidence effects to groundwater resources (see EIS page 3-79 and EIS Figure ] 4 -Subsidence Potential Map). Hydrologic features identified on the CDMG permit Geology/Hydrology Map 2.04-M2, generally fall within this low potential for subsidence zone. The sites identified in the EIS and presented in Exhibit 2.04-E4 have overburden thicknesses above the "D" seam ranging from 1475 to 2550 feet. At these high overburden depths, with steep surface terrain and few shallow and no bedrock water resources present, it is anticipated there will be no adverse effects to water resources related to subsidence. INVENTORY AND MONITORING PLAN The Inventory and Monitoring Plan consists of two phases. Phase I is already completed . and currently in effect. Phase I includes the surface and groundwater inventory that has