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Both of these drainages outlet into Ellison Gulch, which is an intermittent stream located south and <br />• east of the mine azea. Ellison Gulch enters Cedaz Creek approximately 2500 feet southwest of the <br />permit azea and Ellison Gulch eventually flows into the Gunnison River at Montrose. <br />The two principal ways that the gravel pit could affect the water quality of the azea downstream is <br />through poor sediment control within the site causing increased sedimentation downstream and by <br />fuel leakage from a ruptured tank. As described in the mining plan, the sediment pond and sediment <br />trap system will be designed to handle the 100 yeaz event for all runoff within the mine azea, and <br />then allow the water to seep into the ground, therefore, no NPDES permit is needed. Fuel leakage is <br />also not a problem since all fuel tanks on site will be part of the portable plants and will have <br />secondary containment as well as strict SPCC Plan procedures for spill prevention and control. <br />2. Groundwater <br />• The gravel deposit consists of recent alluvial material of Quartemary age lying over large <br />thicknesses of Mancos Shale, which is also outcropped over vast azeas on the north and south sides <br />of the Cedar Creek drainage. The two springs which feed the East and West drainages on the site are <br />located in an alluvial layer perched above a less permeable shale zone. The alluvial layer is also fed <br />by irrigation occurring on the mesa northeast of the mine area. The lower shale zone is not the thick <br />Mancos Shale, which occurs at greater depth in the permit area but begins to outcrop in the hills in <br />the vicinity of the permit. No groundwater has ever been encountered in mining from 1977 to 2005 <br />and none is expected for the remainder of mining in the permit azea. The base of the gravel pit <br />excavation is not the true bottom of the alluvium. There is a zone of lazge boulders and unsorted <br />gravels below the base of the pit, Approximately 20 feet below the base is a zone of silty shale that is <br />the true bottom of the alluvial zone. <br />There aze no groundwater wells within reasonable distance to the operation (at least'/: mile radius) <br />that could be affected and even if any wells were within this distance, it would highly improbable <br />BellgazdtPit 1/06 32 <br />