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As of 2008, the applicant considers only Johnson Gulch Spring and Spring 99-1 to <br />be 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/l and an <br />average iron content of 0.42 mg/l as found in samples taken in 1995 and 1996 <br />(Appendix W of permit application). This spring supplies around 10% of the <br />annual flow of Johnson Gulch within the permit area. The Johnson Gulch Spring <br />water exceeds secondary drinking water standards although it is not currently <br />used as drinking water downstream of the mine area. Cottonwood and Wapiti <br />Springs are natural springs and have total dissolved solids concentrations usually <br />around 1200 mg/1, similar to pre-mining levels. <br />The applicant considers that Colt Seep, a seep that was mined through and <br />reclaimed in 1988, discharged from a spoil aquifer. The applicant believes that <br />during the last few years of the Colt Seep's existence, the seep's water quality was <br />improving after having been degraded by mining. <br />The spoil leachate that discharges from spoil springs and fill springs would be <br />diluted during springtime runoff. The leachate from spoil springs has exceeded <br />irrigation quality limits, but is not used for that purpose. Leachate should be <br />acceptable for stock water and wildlife usage. <br />Suspended solids may be elevated in surface waters in a drainage in the permit area early <br />in the mining cycle or fill construction, until reclaimed vegetation is established to <br />control erosion. Sediment control measures described in the permit application will <br />reduce the sediment load added to surface waters. <br />The applicant expects that total dissolved solids (TDS) in some surface water <br />runoff will be higher for a few years after reclamation in an area. The higher TDS <br />levels will occur periodically when the contribution from precipitation and <br />snowmelt is at a minimum (base flow conditions). <br />Leachate that may discharge from the toe of the Horse Gulch Fill probably will <br />cause an increase in the dissolved solids content of natural stream flows in Horse <br />Gulch. This stream segment is classified as "Aquatic Life Warm 2", indicating <br />waters that are not capable of sustaining a wide variety of cold or warm water <br />biota, including sensitive species, due to physical habitat, water flows or levels, or <br />uncorrectable water quality conditions that result in substantial impairment of the <br />abundance and diversity of species. The discharge rate of leachate from the toe of <br />the Horse Gulch Fill can be expected to average approximately 31 gallons per <br />minute over several months each year (permit application page 4-235). <br />Rain or snowmelt provides most natural surface water flows in Horse Gulch. A <br />natural spring, the Horse Gulch Spring, also provides flow. This spring is located <br />approximately 2,000 feet downstream from the toe of the Horse Gulch Fill. The <br />Horse Gulch spring has flowed at rates between 1 and 25 gpm for several months <br />in wetter years, and has been dry when visited in some years, as documented in <br />Trapper's annual hydrology reports. Although flows from the Horse Gulch spring <br />Trapper Mine 28 September 21, 2009