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ditch. Last year, for what it deemed inadequate diversion ditches above the <br /> refuse piles, DMG took enforcement action against Mid-Continent (NoV C-93- <br /> 096), citing Failure to maintain a stabilized diversion channel to pass safely the <br /> runoff from a 100-year, 24-hour precipitation event as required by 4.09.2(7). <br /> Submittal of Technical Revision 25 was required as an abatement step. <br /> While Channel A appears (from the attached diagram) to run between the <br /> southerly portion of the refuse pile and the sediment ponds, the explanation <br /> given at the pre-bid meeting is that the ditch leads to the sediment ponds. <br /> If the ditch is constructed to by-pass the ponds, then runoff from the disturbed <br /> area will be untreated. This runs counter to the requirements of the law and <br /> regulations. <br /> 4.05.2 Water Quality Standards and Effluent Limitations <br /> (1) All surface drainage from the disturbed area, including disturbed areas that <br /> have been graded, seeded, or planted, shall be passed through a sedimentation <br /> pond, a series of sedimentation ponds .... <br /> On the other hand, the ponds were not sized to receive runoff from the <br /> undisturbed drainage. So, if the ditch does route flows to the ponds, their <br /> capacity would be inadequate to handle a large storm. The practical effect could <br /> be a blow-out of the ponds. In any case, the regulatory requirements for pond <br /> size and capacity are not met under the bid package plan: <br /> 4.05.6 Sedimentation Ponds <br /> (3) Sedimentation ponds and sedimentation treatment facilities shall be <br /> designed, constructed and maintained to: <br /> (a) Provide adequate capacity to contain or treat the runoff or inflow <br /> entering the pond as a result of 10-year, 24-hour precipitation event.... <br /> Runoff directed from the undisturbed drainage areas and not passed <br /> through the sedimentation pond in accordance with 4.05.3 and 4.05.4 <br /> need not be considered in sedimentation pond design; <br /> The size of the channel, and the volume of rock material necessary to meet the <br /> riprap specifications is also a source of concern. <br /> Greg Lewicki, who was hired as an experienced reclamation expert on the <br /> recommendation of the DMG, and who designed the drainage system approved <br /> in TR-25, was asked to review the bid package plan. He notes that there is a <br /> discrepancy in the bid package as to the size of the channel. It is described in <br /> the narrative as 3500' long, having a 10' width; however, the accompanying <br /> diagram shows a width of 20'. <br /> At the pre-bid meeting a field calculation as to the volume of rock material <br /> needed was 2800 yds3. Mr. Lewicki calculates the necessary volume of riprap to <br /> meet the bid package requirements for Channel A is 3240 yd3, assuming a 10' <br /> MCR Objections/DMG Bid <br /> Page 4 <br />