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<br />-34- <br />There are two roads within the proposed permit area: the facilities area haul <br />road and the county mine access road. The mine haul road consists of a short <br />70 foot road segment from the existing county road to the Lewis Gulch Fill. <br />Most of the road drainage will be routed through the sediment control system <br />by roadside ditches. These ditches will contain numerous check dams to <br />control water velocity and erosion. <br />Twin Pines Coal Company, Inc., on page 72 of the application, and Map TP-4 and <br />TP-4 reference drawing, has proposed to upgrade 3,500 feet of the county road <br />from Oak Creek to the surf ace facilities area as an access road. The driving <br />surface will be expanded to 20 feet in width by excavating and regrading the <br />uphill cut slope. No redisturbance will occur on the embankment fill <br />downslope from the existing road, adjoining Lewis Gulch. Six culverts are to <br />be placed at 400-700 feet intervals to drain the ditch along the cut slope. <br />The outfall of the culverts will have 6-inch diameter cobble and 12-inch thick <br />chutes to protect the fill slope. The crossing of Oak Creek is concrete, <br />designed as a low water crossing, which will pass the 10-year, 24-hour event <br />with overtopping. This alternative design for the road crossing was analyzed <br />by a professional engineer ensuring that it will be environmentally sound and <br />structurally stable. Therefore, pursuant to Rule 4.03.2(1)(e), the Division <br />approves the alternative design of the Oak Creek crossing. <br />The application presents, in Volume I, pages 86-88, a reclamation plan, which <br />includes regrading, scarifying and seeding of the haul roads. The access <br />road, being a county road, has been approved by the Division as part of the <br />post-mining land use. <br />The Division finds Twin Pines Coal Company, Inc. in compliance with the <br />requirements of this section. <br />XVII. Ponds, Impoundments, Diversions - Rule 2.05.3 and 4.05 <br />As a result of surface and underground disturbance at the Twin Pines No. 2 <br />Mine, water discharged from the mine would be high in total suspended solids. <br />To mitigate this condition, the operator has designed a sediment control <br />system which will remove suspended solids prior to the water being discharged <br />to the receiving stream. The final water discharged will meet federal NPDES <br />discharge requirements and will not exceed Colorado Department of Health <br />Receiving Stream Standards. The Division reviewed the sediment control system <br />for compliance with the Regulation. <br />A discussion of the drainage and sediment control system, as well as detailed, <br />certified engineering design, can be found in Volume 1, Section 2.05 and in <br />Volume 2, Mine Site Plan Map. <br />The operation utilizes one upland diversion ditch that diverts undisturbed <br />drainage away from the active, disturbed areas. This practice reduces the <br />volume of water that comes in contact with disturbed areas and, therefore, <br />reduces the amount of water needing treatment prior to discharge. <br />