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iii iiiiiiiiuiii iii <br />STATE OF COLOl~vO <br />DIVISION OF MINERALS AND GEOLOGY <br />Depatlmem u( Nalu ral Resources <br />I } I }Sherman St., Ruom ? 1 5 <br />Denver, C°luradu 80?O3 <br />Phrrne: (1031 f1G5-3567 <br />FA%: 13011 ri R-H106 <br />3 February 1998 <br />Mr Michael Altavilla <br />Seneca Coal Company <br />P.O. Drawer D <br />Hayden CO 81639 <br />1I~ <br />DEPARTMENT OF <br />NATURAL <br />RESOURCES <br />Roy Romer <br />Governur <br />lames 5. Lochhead <br />E~rcuuve Dirpaor <br />Alichael B. LnnF <br />Dirisipn Director <br />Deaz Mr Altavilla: <br />The Division has reviewed your submittal for Technical Revision 09, As-Built Drawings for <br />Haul Roads A and B. This review has tamed up some problems that are listed below. <br />Page 18 of Tab 13 paragraph 2 states that "each haul road will be constructed ... to safely <br />convey the 10 yr. 24 hr. precipitation event to sediment ponds." This paragraph needs to <br />be rewritten since all the haul road runoff is not designed to be conveyed to sediment <br />ponds. <br />2. Concerning the actual certification of Haul Road B, there aze two instances in the <br />introduction where the engineer certifies work being done on Haul Road A instead of <br />Haul Road B. These errors aze found in pazagraphs 2 and 4 in the construction summary <br />section. Please correct. <br />The approved plans from the original permit show vertical alignment designs for Haul <br />Road B at station 56+00 to station 62+00 to be 6.37%. The as built drawings for this <br />same section range from 14.61 % to 15.32%. Rule 4.03.1(3)(a)(ii) and (iii) state that the <br />maximum pitch grade shall not be steeper than 15%, and (iii) there shall not be more than <br />300 feet of pitch grade exceeding 10% within any consecutive 1000 feet. The failure to <br />comply with the regulation on maximum grade and failure to comply with the design <br />approved within the permit application requires that a Notice of Violation be written. <br />This vertical alignment may also significantly affect the designed drainage associated <br />with this section of the haul road rendering the generic typical cross section of the road <br />and associated ditch to perform as designed. Erosive velocities on this section of the road <br />would necessitate designs for energy dissipators or riprapped channels to curb the erosive <br />velocities of the runoff. <br />4. There were no as-built cross sections of road provided, only the "typical cross sections ~. <br />Since cut and fill slope gradient was a concern of the Division during the construction of <br />the road, especially at some of the deeper fills, perhaps the operator could provide some <br />