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The Yampa River alluvium and the Williams Fork River alluvium both contain alluvial ground water. These alluvial water-bearing units may store and release water used by the overlying vegetation, and may sustain a component of baseflow to the associated river systems. These alluvial units may provide recharge to rock aquifers and also are recharged by rock aquifers within the ground water study area. Empire Energy Corporation analyzed the quantity and quality of ground water in the alluvium of the Yampa River and Williams Fork River. Previous Williams Fork alluvium tests conducted for Empire Energy were suspect and Empire Energy Corporation reran the tests. The result„ of the rerun tests are contained in Appendix III-3A. Given the relativel~r thin saturated thickness (five to six feet) and low well yields (less than one gpm), these wells were slug tested and analyzed by the Bower and Rice Method, 1976. Low transmissivity values of between 38 to 130 gpm/ft and low permeability values of between 5.5 and 24 gpd/f t= were obtained for the Williams Fork alluvium. Slug testa and pumping tests were run on the Sig Bottom alluvium. Transmiesivity values and permeability valueee obtained for the Big Bottom alluvium were low; tranemiesivities ranged between 57 and 3,100 gpd/ft and averaged 900 gpd/ft; permeabilities ranged between 12 and 440 gpd/f t1 and averaged 120 gpd/ft~. These tests indicate that the alluvial bodies of the Williams Fork and Yampa Rivers a.re poor aquifers in the general area. Alluvial water quality ie variable, depending on the underlying rock and source of alluvial material. Ground water from the Yampa River alluvium is primarily sodium sulfate type. Dissolved solids average 4,586 mg/1 with a maximum measure of 8,810 mg/1. Ground water for the Williams Fork alluvium is primarily of the sodium bicarbonate type. Total dissolved solids average 1,009 milligrams per liter (mg/1) with a maximum measured value of 1,510 mg/1. Maximum primary and secondary drinking water standards are exceeded in both aquifers for many parameters including barium, cadmium, chloride, chromium, pH, sulfate, sad selenium. In addi~tibn, average concentration values for chloride, total dissolved soli~9s, iron, lead, manganese, and sulfate exceed EPA primary and secondary standards. There are six springs within the permit and adjacent areas of the Hagle Mines. The North Spring, also referred to ae the Lippard No. 1, originates at the head of a small drainage near its junction with old Highway 13 along the base of a thin Pleistocene or .Quaternary gravel that caps many terraces in the area. The East Spring flows from the base of a highway fill and appears to be a man-made situation. Approximately one mile south of the No. 5 Mine portal, the South Spring is located on a hillside west of the Williams Fork River. Water issues from a sandstone lene~ within the Iles Formation. A small seep is found at the No. 9 Mine £acE,-up. This spring flows only in the spring and dries up in the sun¢ner. TYie Haxton Spring originates in a weathered, brown-gray, very fine-grainer! sandstone. A pipe has been set in the ground at the spring, but no flow ha.s been observed. In total, flow from the springs is less than 20 gpm. The springs that were surveyed do not appear to be discharge zones for any of the regional bedrock aquifers and are not considered significant. In addition to the springs discussed above, a seep has been observed issuing from the base of the old Williams Fork Strip Pit No. 1. Water percolates through the regraded spoils of the~Williams Fork Strip Pit No. 1 and drains into the Williams Fork River. Mean flow is 58 gpm, ranging from 4 to 198 gpm. This appears to be created by old mining 3isturbances by filling a local drainage with mine spoils. Discharges from the springs and strip pit have relatively poor quality. 19