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The remaining ponds, Pond 4 and Pond 5, located at the mine, are intended to <br />remain as permanent structures at the request of the associated landowners. <br />At the loadout, Pond L 1 and Pond L2 are sediment control structures. EFCI plans to <br />reclaim both ponds prior to requesting final bond release of the loadout site. <br />The two (2) existing sedimentation ponds in the mine area and the two (2) ponds at the <br />loadout area, along with associated collection ditches, spillways, and discharge <br />structures provide effective drainage and sedimentation control for both existing and <br />proposed future surface disturbance. These existing sedimentation ponds were <br />designed using standard USDA -SCS methods to contain the runoff resulting from a 10- <br />year, 24 -hour storm event as well as accumulated sediment. All ponds and associated <br />components including collection ditches, inlet channels, embankments, outlet <br />structures, discharge structures and outlet channels were designed and constructed to <br />ensure long term structural integrity and provide sufficient storage capacity. EFCI <br />previously utilized a separate water treatment and recycle pond (Pond 3) to collect and <br />retain water resulting from mine dewatering activities (Pond 3 was reclaimed pursuant to <br />mine closure). Consequently, it has not been necessary to incorporate mine pumpage <br />volumes in determining sedimentation pond capacity. <br />Discharge structure designs for the sedimentation ponds provide for a minimum <br />detention time of 24 hours and allow for effective dewatering under design storm <br />conditions as dictated by applicable regulations. <br />All areas disturbed by mining and related operations were reclaimed as soon as <br />operationally practical following completion of mining. Reclamation involved <br />backfilling and regrading disturbance areas, replacement of topsoil, and revegetation, <br />resulting in re- establishment of drainage patterns similar to those existing in the pre - <br />mining environment and development of a self - sustaining vegetative community. As a <br />result of effective reclamation, infiltration and runoff relationships are being restored, <br />limiting the time interval over which water quality impacts may occur. Where <br />appropriate, EFCI utilized localized drainage control measures to prevent or mitigate <br />potential impacts from operations. Such measures included use of surface binders and <br />dust suppression agents on haulage roads, topsoil stockpiles, and in active working <br />areas, placement of straw bales, sediment fence, erosion netting, mulch, berms, stilling <br />basins, sumps and other small structures to control and route drainage, <br />2.05.6 -18 Revised: 8/1/14 RN -06 <br />