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spoil-filled pit will fill with water and likely will eventually develop a spring on the <br />ground surface at the pit's down-slope (north) end. The pit effluent that discharges from a <br />spring will be composed of water that is rich in the minerals that are dissolved from the <br />coal spoils which fill the mined-out pit. The effluent discharging from a spring will flow <br />down the north slope of Trapper Mine in one of the northward-flowing drainages that <br />cross the permit area. <br />As of 2002, the applicant considers only Johnson Gulch Spring and spring 99-1 to be <br />spoil springs. All other springs on Trapper are believed to be natural springs. <br />Water from Johnson Gulch Spring has a TDS level of around 4000 mg/1 and an average <br />iron content of 0.42 mg/1 as found in samples taken in 1995 and 1996 (Appendix W of <br />permit application). This spring supplies around 10% of the annual flow of Johnson <br />Gulch within the permit area. The Johnson Gulch Spring water exceeds secondary <br />drinking water standards although it is not currently used as drinking water downstream <br />of the mine area. Cottonwood and Wapiti Springs are natural springs and have total <br />dissolved solids concentrations usually around 1200 mg/1, similar to pre-mining levels. <br />The applicant considers that Colt Seep, a seep that was mined through and reclaimed in <br />1988 discharged from a spoil aquifer. The applicant believes that during the last few <br />years of the Colt Seep's existence, the seep's water quality was improving after having <br />been degraded by mining. <br />The spoil leachate that discharges from spoil springs is diluted during springtime when <br />surface runoff peaks. The leachate exceeds irrigation quality limits but is not used for that <br />purpose. Leachate is acceptable for stock water and wildlife usage. . <br />Suspended solids may be elevated in surface waters in the permit area early in the mining cycle <br />of a drainage until reclaimed vegetation is established to control erosion. Sediment control <br />measures described in the permit application will reduce the sediment load added to surface <br />waters. <br />The applicant expects that total dissolved solids (TDS) in some surface water runoff will <br />be higher for a few years after reclamation in an area. The higher TDS levels will occur <br />periodically when the contribution from precipitation and snowmelt is at a minimum <br />(base flow conditions). <br />The post-mining pH values are not expected to be significantly different from baseline <br />values. Total iron and manganese concentrations are likely to continue to be relatively <br />high at times, similar to the pre-mine condition. <br />IV. Topsoil <br />Soil information can be found in Section 2.6, Volume II and Section 4.9, Vol. IV.' <br />Trapper Mine 25 July z5, zuuu