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Chapter II <br /> total suspended solids content meets federal/state standards, treat it if it is polluted, <br /> release it into the Coal Creek drainage system and monitor its quality to ensure that <br /> the required standards are being met. <br /> Surface drainage from the Coal Basin portion of the permit area enters Coal Creek, <br /> more than four miles before it flows into the Crystal River. <br /> Design and construction of the drainage/sediment control system has been done by <br /> specific area: <br /> - Portal areas <br /> - Haul road system <br /> - Preparation plant area <br /> - Adit/Rock Tunnel area <br /> - Coal refuse disposal area <br /> (1) Portal Area Drainage and <br /> Sediment Control Plan. <br /> The plan followed by Mid-Continent was developed by Morrison-Knudsen Co., Inc. <br /> It consists of a system of diversion ditches, culverts and sedimentation ponds. <br /> Drainage from the mines and the surface disturbed areas in and around the five <br /> mine portals is diverted into sedimentation ponds and held until excess total <br /> suspended solids have settled out. <br /> The plans for drainage and sediment control in the mine portal areas, prepared by <br /> Morrison-Knudsen Co., are in Attachment 1 to App. II-B-7. <br /> (2) Roads. <br /> Haul/access roads cross three major drainages: Coal Creek; Dutch Creek and <br /> Bear Creek. There are 13.7 miles of haul or access roads for which a drainage <br /> control plan was developed and implemented. Dutch Creek is the most affected, <br /> with 11 miles of road found in the Dutch Creek drainage. <br /> The drainage control system was originally designed by Fleming & Associates, Inc. <br /> and the engineering staff of Mid-Continent, and 57 culverts were installed along the <br /> haulage roads. Further study and evaluation of the system was done by the <br /> Morrison-Knudsen Co, who recommended installation of 17 additional culverts. <br /> The Morrison-Knudsen plan was developed for the purpose of ensuring compliance <br /> with the applicable performance standards (4.03.- Performance Standards for Haul <br /> Roads). In their evaluation of the system, Morrison-Knudsen used design criteria <br /> based on MLRD/OSM regulations for haul roads. The Morrison-Knudsen drainage <br /> control plan is in Attachment 2 of App. II-B-7. <br /> 25 <br />