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<br />Williams Fork Mines Prepared by: R. Reilley M.S. GISP <br />C1981044 5 November 2018 <br /> <br /> <br /> 8 <br />source of alluvial material. Ground water from the Yampa River alluvium is primarily sodium sulfate type. <br />Dissolved solids average 4,586 mg/l with a maximum measure of 8,810 mg/l. Ground water for the Williams <br />Fork alluvium is primarily of the sodium bicarbonate type. Total dissolved solids average 1,009 milligrams per <br />liter (mg/l) with a maximum measured value of 1,510 mg/l. Maximum primary and secondary drinking water <br />standards are exceeded in both aquifers for many parameters including barium, cadmium, chloride, chromium, <br />pH, sulfate, and selenium. In addition, average concentration values for chloride, total dissolved solids, iron, <br />lead, manganese, and sulfate exceed EPA primary and secondary standards. <br /> <br />Natural Springs and Seeps. There are six springs within the permit area and adjacent areas. The North Spring, <br />also referred to as the Lippard No. 1, originates at the head of a small drainage near its junction with old <br />Highway 13 along the base of a thin Pleistocene or Quaternary gravel that caps many terraces in the area. The <br />East Spring flows from the base of a highway fill and appears to be a man-made situation. The South Spring is <br />located on a hillside west of the Williams Fork River approximately one mile south of the No. 5 Mine portal <br />where water discharges from a sandstone lens within the Iles Formation. A small seep is found at the No. 9 <br />Mine face-up. This spring flows only in the spring and dries up in the summer. The Haxton Spring originates <br />in a weathered, brown-gray, very fine-grained sandstone. A pipe has been set in the ground at the spring, but <br />no flow has been observed. Aggregate flow from the springs is less than 20 gpm. The springs that were <br />surveyed do not appear to be discharge zones for any of the regional bedrock aquifers and are not considered <br />significant water sources. <br /> <br />Spoil Springs. Water seeps from the base of the old Williams Fork Strip Pit No. 1 and drains into the Williams <br />Fork River. Presumably the water percolates through the regraded spoils of the pit. Flow has ranged between <br />4 gpm and 198 gpm. Total dissolved solids have averaged around 1,000 mg/l. <br /> <br />Soil Types. The permit area is occupied by three soil orders: Aridisols, Entisols, and Mollisols. These soil <br />orders are characteristic of fairly steep, semi-arid regions of northwestern Colorado. They represent soils that <br />grade from recently developed soil bodies with minimum horizon development (Entisols) to older soils with <br />well-defined diagnostic horizons (Mollisols). <br /> <br />Soil Characteristics and Distribution. Overall, the soils found in the proposed permit area are relatively deep <br />and fairly well-drained. Effective rooting depth varies from two to sixty inches within the area. The deepest <br />soils yielding the greatest rooting depths occur in valleys and on the leeward sides of ridges. Soil reaction is <br />slightly acid to moderately alkaline in the permit area with the exception of small scattered areas where <br />substrata are saline. These small areas have probably formed in place from weathered sodic shales. <br /> <br />Vegetation Communities. Vegetation communities in the permit area range from an upland mountain shrub <br />community to cottonwood-willow communities in the riparian zone next to the Williams Fork and Yampa <br />Rivers. Juniper or big sagebrush communities dominate more xeric sites throughout the permit area. Lands <br />disturbed by mining are upland big sagebrush and mountain shrub communities, croplands, and previously <br />mined lands. The croplands are previously mined lands. There are two types of croplands: 1) irrigated <br />hayfields in the fertile river bottom areas, and 2) dryland wheat, found on cleared hillsides which were once <br />sage-dominated. Several areas disturbed by former mining operations are within the disturbed areas. <br /> <br />Wildlife. Wildlife habitat in the permit area is diverse. It is used extensively by mule deer, elk and pronghorn <br />antelope. Known predators include badger, cougar, coyote, red fox and bobcat. Small game and furbearing <br />mammals include the cottontail rabbit, white tailed jackrabbit, raccoon, beaver, muskrat, striped skunk and <br />weasel. Many species of birds are also found within the permit boundary. Of special interest are various <br />species of waterfowl, raptors (including the golden and bald eagles), the sandhill crane, Columbian sharptail <br />grouse and the Greater sage grouse. Fish species in the Williams Fork River, within the affected area, include