GENERAL46097 - Laserfiche WebLink

Home Browse Search

Tributaries to Fish Creek have historically exhibited ephemeral chazacteristics, but mining-related groundwater discharges may increase the flow in these tributary streams. This is discussed in the Probable Hydrologic Consequences (PHC) section of the permit application package (Volume 4, Tab 7). The increase hi flow is due to the changing of the ground water system from a structurally controlled artesian aquifer to a topographically controlled unconfined system. This change increases the amount of groundwater available for dischazge into the surface water system. At the Seneca II Mine this may increase the the flow of Grassy Creek, Little Grassy Creek, and the unamed tributaries of Fish Creek. Climate Annual precipitation at the mine site is 16.11 inches. The precipitation is consistent throughout the yeaz with no significant dry periods. The average temperature in January is 17.1 °F and is 65.9°F in July. Regionally, wind directions run east-west following the Yampa River Valley. More localized wind patterns trend along the side valleys. Land Use Current and historic land use in the vicinity of the operation has been mining, grazing for livestock, and wildlife habitat. Irrigated cropland in the area is limited to portions of the Fish Creek alluvial body and to the Yampa River floodplain. Non-irrigated crops are grown on sloping upland areas, as well as on alluvial flats. No cropland was disturbed by mining. Soils The soils found within and adjacent to the mine plan azea aze typical of soils found in the cold, semi-azid regions of the Western United States. The soils aze moderately deep (20 to 40 inches) to shallow~l0 to20.inches). Soils were developed in weathered; interbedded-fine sandstone, siltstone, and shale, and in local slopewash and colluvium. Vegetation Three vegetative types; mixed brush, sagebrush grassland, and aspen chazacterize vegetation in the vicinity of the operation. Because of livestock grazing, shrubs have increased in density while forbs and grasses have decreased. Fish and Wildlife Numerous wildlife species inhabit the general azea of the mine site. The most predominant big game species aze elk and deer. Common raptors are Golden Eagle, Red-Tailed Hawk, Great Horned Owl, Mazsh Hawk and American Kestrel.