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construct additional drains that will remain upon final reclamation. In addition, MCC will update Exhibit 14c to include these drains and evaluate them for the final reclamation plan. (4) Ponds, Impoundments, and Diversions During the course of construction and operation of the mine facilifies at the West Elk Mine, every effort is made to minimise water pollution. It is MCC's intent to discharge water from sediment ponds, Small Area Exemptions, and from the mine in compliance with ail applicable effluent limitations. To fulfill this commitment all surface drainage from the affected mine azea is collected and treated prior to being discharged from the permit azea. All surface runoff from undisturbed azeas is duected away from the affected mine azea through diversion channels. Map 54, 54A, and 54B shows the distribution of sediment control structures at the West Elk Mine. Map 54 and Map 54A identifies the sub watershed drainage basins, tributary drainage basin information, and ditch/culvert layouts in conjunction with the main surface facilities azea and Lone Pine Gulch, respectively. Map lE, 2E and 3E in Exhibit 66 identify the watersheds in the Sylvester Gulch Facilities Area. Map 54B shows the ditch and culvert locations in conjunction with the Sylvester Gulch Facilities Area. The following sections deal with each specific hydrologic protection measure. Studies have been made that estimate the peak runoff and flood volume for storms having specific recurrence intervals for the West Elk Mine azea. Exhibit 44 is the report used in the design of the original sedimentation ponds (MB-1, MB-2, and MB-3), ditches and culverts by Merrick and Company. This report was submitted to the State Engineer for the approval of the three sedimentation ponds MB-1, the original MB-2, and MB-3, and the freshwater pond, FW-1. Approval was received on February 3, 1981, and is included in Exhibit 45. Exhibit 66 contains the new designs for ponds MB-2R and MB-3. The Exhibit 43 and Exhibit 44 designs aze no longer valid for these ponds. Exhibit 66 contains an as-built drawing that reflects the addition of a dike in the pond to create a north and south cell. However, the drawings included in Exhibit 43 do accurately reflect other structures associated with MB-1 (i.e., the primary and emergency spillways). Exhibit 66 also contains the design information for SG-1 located at the Sylvester Gulch Facilities Area. See Exhibit 46 for the original design specifications and for the current designs for MB-4, Unit Train Loadout Sedimentation Pond. Pond MB-4 was relocated in 1998 from the east side of the train load-out to an azea west of the load-out between two sets of train tracks. The relocated sediment pond is constructed of concrete and is preceded by an oil skimmer and a sediment trap. Design criteria for Ponds MB-5 aze contained in Exhibit 47, and an as-built survey is contained in Exhibit 66. Ponds MB-2 and MB-6 no longer exist and were replaced by new pond MB-2R. Design criteria for the Refuse Pile Expansion (RPE) pond, designated the "RPE" pond, aze included in Exhibit 70. Hydrologic Design of Runoff Ponds Seven storm drainage sediment control structures aze used as settling ponds for storm water runoff from the mine site. These ponds have been designed according to CMLRB regulations (see Exhibits 43, 47, 66, and 70). 2.()5-2g Revrsed Jan 1996 RN03; Revised Nov. 7996 PR07; Revised Jars. 1997 TR79; Revrsed Jul 1997 TR81 Revised Oct. 1998 TR86; Revised Jun. 7999 TR90