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<br />The recharge areas for the strata that will be disturbed by <br />mining are located down dip from the coal seam. The area is not <br />transected by any perennial streamflow, so all recharge is in <br />direct response to precipitation events. The applicant has not <br />quantified the recharge to the strata to be mined, but has con- <br />cluded that recharge is minimal, if not negligible, due to: 1) <br />the low annual precipitation in the mine plan area of eleven <br />inches; 2) the sloping topography of the recharge area wihich pro- <br />motes runoff, and therefore tends to decrease infiltration rates; <br />and 3) the interbedded and lenticular nature of the sandstone and <br />siltstone members of the Coalmont Formation, which tends to re- <br />tard infiltration. In addition, transmissivity {21 9pd/ft2) and <br />permeability (20.1 gpd/ft2) values are low in these strata, lead- <br />ing to minimal recharge. <br />Groundwater quality in the strata to be mined is predom- <br />inantly a sodium bicarbonate type, with minor incidences of <br />sodium hydroxide and sodium sulfate present. The high sodium <br />levels are thought to be a direct result of the high sodium con- <br />centrations in the overburden and underburden. <br />Total dissolved solids concentrations in the groundwater are <br />high (ranging from 1,400 mg/1 to over 7,000 mg/1 ), with the <br />highest levels being recorded in the alluvial aquifer. The TDS <br />values tend to increase as the groundwater moves downgradient. <br />Therefore, the groundwater is generally poorly suited for domes- <br />tic use. In some instances, the high sulfate and TDS values also <br />present severe limitations for use of the water for irrigation. <br />However, for the most part, the groundwater is suitable for agri- <br />cultural use, and also for stock watering. <br />The flow from the seep in the headwaters of the North Fork <br />of Bolton Draw is collected in a small pond (0.08 acres) for <br />stock watering. Because the flow from the seep is very minimal, <br />discharging only in response to precipitation/infiltration <br />events, no water rights of record exist for the seep or the pond. <br />-25- <br />