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• Ocean Wave coal, within the Vermejo Formation. The direction of ground water movement within the coal <br />can be considered to be representative of the general direction of ground water movement in the Venmejo as a <br />whole. Local gradients and direction of flow in the ground water system may vary due to variations in geologic <br />and hydrologic properties. Also there are no significant aquifers in the permit azea because of the <br />discontinuous nature of the geologic deposits and the low permeabilities of the formations. <br />During a site visit in January, 2006, springs were observed where the Ocean Wave seam outcrops at the surface <br />neaz the mouth of Chandler Creek on the northeastern side of the Chandler syncline, as summarized in Table 2. <br />This observation generally confirms the monitoring well data., which indicate that ground water movement is to <br />the north. <br />The principal sources of recharge aze direct precipitation on the subcrop or outcrop and surface runoff from <br />streams originating in the Wet Mountains. Recharge to the deep ground water system is limited due to low <br />annual precipitation, high surface water runoff, and evapotranspiration. Figures 7 and 8 aze schematic <br />diagrams that illustrate hydrologic conditions prior to and during mining, respectively. During mining, water <br />enters the mine cavity through inregulazly distributed fractures in the formation and from adjacent abandoned <br />• mine works, and as a result, the potentiometric surface of the coal being mined is lowered. The mine cavity <br />intercepts the water before it is discharged to the land surface. Water will be pumped from the mine, probably <br />used for different purposes, partly consumptively used and then a portion returned to the stream system. This <br />may result in a gain to the stream system during mining. A review of other monitor well water level data for a <br />neazby mining project indicated that, typically, the extent of lowered water levels as a result of mining is <br />confined to the immediate vicinity of the mining area, because of the low permeability of the coal seams and <br />the discontinuous nature of the geologic units. <br />WATER REQUIREMENTS AND CONSUMPTIVE USE <br />Northfield Mine dewatering will be accomplished by underground pumps. The pumps may dischazge <br />mine inflow to a fresh water pond. Water from this pond could be distributed via a second fresh water <br />pond to all phases of the mining operation, if needed. Further analysis is needed to evaluate the practical <br />benefit of possibly using another source for mine water requirements, such as a nearby well. <br />-12- <br />