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IV. Unnecessary Expenpenditures and Increased Costs <br /> I. The Drainage Plan. <br /> Technical Revision JR) 25 (See Attachment B) was approved by the DMG on <br /> September 16, 1993 after completion of a technical review by Division <br /> hydrologists of the plans developed by Greg Lewicki, P.E. The TR specified <br /> certain modifications to the drainage control structures as part of final <br /> reclamation of the Sutey refuse disposal site to ensure compliance with the <br /> performance standards of the regulations. <br /> The approved plan. Under the approved plan (TR-25) a ditch intercepts flows <br /> from the undisturbed area above the refuse pile. The ditch is sized to handle a <br /> 100-year 24-hour storm event. The channel is lined with a bio-degradable <br /> coconut fiber blanket, and seeded as a means to stabilize and prevent erosion of <br /> the ditch. <br /> Runoff from the disturbed area (i.e. the refuse pile) continues to flow to sediment <br /> ponds by way of collector ditches on the east and west side(s) of the pile. Two <br /> contour ditches are established on the pile. Their function is to re-direct flows <br /> away from the east to the west collector ditch, and to prevent gullying by <br /> intercepting runoff as it flows down the long face of the pile. The east collector <br /> ditch is to be reconstructed, with the fiber mat to replace riprap. (See <br /> Attachment C) <br /> DMG bid package plan. The DMG bid package does not follow the plan <br /> approved by TR-25. This bid package calls for construction of three channels, <br /> identified as Channels A, B and C, (see Attachment D) and also provides that <br /> "dozer basins" may be installed on the pile itself, and on the base of the pile. <br /> The bid package describes the scope of work as follows: <br /> DMG BID DOCUMENT <br /> TASK 2 SURFACE DRAINAGE <br /> The diversion ditch (Channel A).... must be reconstructed in order to safely <br /> pass flows from the refuse pile and from the adjacent drainage area. The <br /> diversion will be 3,500'long, 10 feet wide at the base and the top of the side <br /> slopes, will be no less than five (5) feet above the ditch invert. Side slopes shall <br /> not exceed 3H:1 V. Riprap with a median diameter(D-50) of ten inches <br /> (maximum diameter not to exceed eighteen inches) will be placed in the channel <br /> to a depth of twenty(20) inches over a well-compacted subgrade (see Drawing <br /> A). After placement, the riprap surface will be worked to be well graded with the <br /> voids choked with small cobbles and stones. A source of riprap within the mine <br /> site area will be identified by the CONTRACTOR, subject to approval of the <br /> PROJECT MANAGER. The material will consist of durable sandstone or <br /> metamorphosed shale materials. Unaltered Mancos Shale is not acceptable for <br /> riprap. <br /> MCR Objections/DMG Bid <br /> Page 2 <br />