Laserfiche WebLink
~ ~ III IIIIIIIIIIIII III <br />STATE OF COLORADO <br />Roy Romer, Govei <br />~I.. <br />DEPARTMENT OF NATURAL RESOURCES <br />MINED LAND RECLAMATION DIVISION <br />FRED R. BANTA, Director <br />December 14, 1987 <br />Mr. Terrell K. Johnson <br />Environmental Specialist <br />Yampa Valley Coal Corporation <br />29588 Routt County Road No. 27 <br />Oak Creek, Colorado 80467 <br />Re: Technical Revision No. 12 (TR12) -Proposed Permanent Roads - C-81-07T <br />Dear htr, Johnson: <br />We have reviewed your adequacy response submitted October 28, 1987, and <br />several concerns have been identified. The issues discussed in this letter <br />must be resolved, prior to the staff approving the revision request. We <br />realize that you may not be able to respond to our questions by December 18, <br />1987, so please feel free to request additional time. Our canments are <br />separated into four categories: Area 41 Haul Road Fill, Pond A Areas, Other <br />Areas and Revision Pages. <br />Area 41 Haul Road Fill <br />The existing permit indicates that the road fill material will be hauled to a <br />disposal site. The operator is now proposing to grade the Area 41 fill <br />material throughout the local drainage, The Division has several concerns <br />with regard to the proposed plan. <br />The existing longitudinal channel profile, in the area of the road fill, is <br />generally concave with a maximum slope of 10,6a. Map TR-87-12-4 indicates <br />that the existing channel contains a small section (about 150 feet long) with <br />a slope of 21,4, located 500 to 600 feet downstream from the road fill. The <br />proposed topography diagram (Map TR-87-12-4) indicates that the concave <br />channel area will be replaced by a convex configuration with maximum slopes of <br />10.3b and 13.5x, Riprap is proposed for the sections of channel with slopes <br />of 13.5 and 21.4. <br />The placement of unconsolidated fill in the channel, as proposed, does not <br />satisfy Rule 4.14.2, which requires that "the final graded slopes shall not <br />exceed in grade either the approximate pre-mining slopes or any lesser slopes <br />approved by the Division...". Additionally, the staff is concerned that the <br />proposed configuration will not provide a geomorphically stable channel. <br />423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 7e1. 1303) 866-3567 <br />