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A study was conducted by Morrison-Knudsen in 1982 which proposed installing <br /> seventeen additional culverts along with check structures at designated <br /> locations . The bulk of these recommendations were approved and eventually <br /> installed . <br /> Notices of Violation have been issued to Mid-Continent Resources for various <br /> road maintenance problems throughout the life of their mining and reclamation <br /> permit. Most recently, three violations were issued in the summer of 1991 . <br /> This comprehensive revision was submitted as part of the abatements for these <br /> violations . With approval of this revision, all of the abatements have been <br /> performed or are included in the permit and are scheduled for completion <br /> within the next two years . <br /> The subject of the violations was the level of sedimentation occurring as a <br /> result of the road runoff from the cut slopes , the road surface and the fill <br /> slopes . The contribution of sediment occurs from rill and sheet erosion off <br /> of the cut and fill surfaces and the road surface. It also occurs in <br /> relatively undisturbed areas as a result of discharge from culverts and relief <br /> drains which cause downcutting. Water volume and velocity are rather large at <br /> these culverts and discharge points , hence the need for these structures . <br /> Unfortunately, many of these drains are located in areas that are incapable of <br /> receiving this water without causing serious erosion. Examples of where the <br /> most serious erosion has occurred are over fill slopes that are not properly <br /> vegetated or stabilized or in undisturbed vegetated areas where the topography <br /> is too steep to pass water without erosion occurring. Also, naturally <br /> occurring drainages have displayed accelerated erosion due to concentrated <br /> flows passing through their relatively unstable channels . <br /> The following is a summary of repair work accomplished or to be accomplished <br /> along with practices to be employed for eliminating sedimentation problems . <br /> Strawbale check dams and fences have been installed at various locations <br /> to trap sediment. Other areas are designated to receive similar treatment. <br /> Water bars have been installed at selected locations . In most cases , this <br /> is to prevent rills and gullies on the road surface and not to intercept <br /> and direct flows to the outslopes . <br /> General designs and locations for incised sediment traps have been <br /> submitted. These traps will serve to retain sediment in a location <br /> (generally switchbacks) which can be easily accessed and maintained . <br /> Material cleaned from these traps will be utilized as growth medium for <br /> reclamation . The Division is requiring one stipulation to submit more <br /> detailed designs of the traps , including inlets and outlets . <br /> Stipulation 5: <br /> Mid-Continent Resources , Inc . will submit by August 28 , 1992, plan <br /> drawings and cross-sections of the incised catchment basins proposed for <br /> the controlling of sediment along the road system, along with details of <br /> the outlet/discharge structures , and maps identifying their proposed <br /> locations . <br />