Laserfiche WebLink
<br />iii iiiiiiii ii <br />COAL <br />COMPANY <br />May 20, 1993 <br />Mr. Steve Wathen <br />Reclamation Specialist <br />Colorado Division of Minerals and Geology <br />215 Centennial Building <br />1313 Sherman Street <br />Denver, Colorado 80203 <br />RE: Permit C-81-019 <br />NOV C-93-073 <br />Dear Mr. Wathen: <br />5731 State Highway 13 <br />Meeker, Colorado 81641 <br />(303) 824-4451 <br />~~c~(vFc <br />gar z s 1993 <br />Division U,` ivfinerdl~ ~, Genlo9Y <br />The following information is submitted as additional factual <br />information regarding the above Notice of Violation (NOV). <br />1) The NOV states incorrectly that there was a "Failure to <br />construct appropriate sediment control measures to retain <br />sediment within disturbed areas...". The Section of ditch in <br />question was in fact constructed correctly in 1992 and the <br />entire length has been checked routinely numerous times until <br />made impassible by winter weather. <br />It is important to note that not only did Colowyo <br />construct "appropriate sediment control measures" the ditch in <br />question is vastly overbuilt with respect to the theoretical <br />flow of water predicted in that ditch segment for the design <br />storm event. <br />Attachment 1 is a copy of a preliminary worksheet from <br />the Division showing a predicted discharge through the ditch <br />segment of 3.74 CFS. (Colowyo and the Division have not yet <br />completely resolved a number of hydrologic modeling issues of <br />which this discharge prediction is one component. It is <br />merely being used here for comparison). <br />Attachment 2 and 3 provides an analysis of the Division's <br />flow estimate through the south collection ditch assuming a <br />ditch configuration per Attachment 4 - Typical Cross-Section - <br />South Collection Ditch. The analysis indicates that a flow <br />of 3.74 CFS requires only .49 feet in depth and 3.9 feet in <br />width. Obviously, the ditch is sized appropriately. <br />