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<br />-~- <br />2. The applicant states that no coal processing or non-coal processing <br />waste or underground development waste will be deposited on the surface <br />areas of the mine. In actuality some material is bound to be deposited <br />on the surface areas from the crushing facilities and development <br />activities. The applicant needs to address this material and its <br />placement in the context of the permit application. <br />Ponds, Impoundments, and Diversions <br />3. Rule 4.05.4(2)(b) requires that permanent diversions of watersheds <br />draining greater than one square mile be designed to contain a 100 year <br />- 24 hour precipitation event. The Coal Gulch permanent diversion will <br />need to be redesigned. In addition, the capacity of the diverted <br />channel must be at least equal to the capacity of the unmodified stream <br />channel both upstream and downstream. Cross-sections will be necessary <br />to verify this. Section 4.05.4 of the permit application will need to <br />be revised since the regulations of Rule 4.05.4 also address ephermal <br />streams draining a watershed of greater than one square mile and Coal <br />Gulch falls in this category <br />4. If, in the new Coal Gulch channel design, segmehts will continue to be <br />used, then a map delineating the segments will be necessary. <br />5. Page 4.05-4 states that a discussion of the permanent channel is found <br />in Section 2.05.6, however this page appears to be the only place in <br />the text that the permanent channel is addressed. Please c]arify. <br />6. If Ditch No. 2 is temporary and will be removed upon successful <br />reclamation, then Map 14, Postmining Topography should show this <br />channel re-establishing itself in the gulch that presently catches <br />these flows. <br />7. Ditch No. 1, the permanent diversion should be designed to handle not <br />only the flows from Coal Gulch above the diversion, but also the flows <br />from Ditch No. 2 and the disturbed area since upon reclamation these <br />areas will flow into the permanent diversion. <br />8. The drainage areas are incorrect as shown. If it is the intent of <br />Ditch No. 2 to divert the runoff from the entire gulch above the <br />ditch, the drainage area is incorrect as shown. If it is correct as <br />shown, then the upper portion of the gulch will flow over the portals <br />and fan and onto the disturbed area. It will not be diverted into <br />Ditch No. 1 since this ditch is designed to divert flows upstream of <br />the gulch and the existing gulch is not proposed to be extended to the <br />new diversion. <br />