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affected by the Foidel Creek Mine. The following wells serve as the Foidel Creek Mine's ground water points of compliance: 97013TH (Twentymile sandstone), 008-77-58 (Wadge overburden), 008-AU3 (Fish Creek alluvium), and 008-AT-1 (Trout Creek alluvium). The mine's annual hydrology reports contain long-term data from these wells. These data show the Foidel Creek mine is in compliance with the Basic Standards for Ground Water at the ground water points of compliance. Surface water Several possible effects on the surface water system have been identified. Dischazge of mine inflow water to surface water drainaees Mine water discharged to the surface water system will increase the conductivity, total dissolved solids (TDS), sulfate, and iron concentrations in the streams receiving the discharge. Total suspended solids, SAR, and pH could also increase due to these dischazges. SAR may reach up to 6.2 in Fish Creek and 3.0 in Trout Creek. Sulfate and conductivity impacts are predicted for various segments of the stream system to be affected. TR-32 approved a plan that will allow the mine to dischazge considerable volumes of degraded water during high flow (great dilution capacity) and lesser or no dischazge during periods of low flow (minimal dilution capacity). Lower Middle Creek -Impacts in this segment will be pronounced due to relatively small instream flows. There is no sulfate or irrigation standard over this reach. However, due to standazds on Trout Creek immediately below this segment, impacts will be minimized during most times of the yeaz. Lower Fish Creek- The mine pumps underground mine water into Fish Creek at site 115. This pumping may significantly degrade water in Fish Creek and the water in Trout Creek, downstream from Fish Creek. The degradation would be high dissolved solids, mainly sulfate. The Division applies a material damage standard to the Fish Creek alluvial valley floor of 1500 umhos/cm. This standard is based on the salinity level in irrigation water that would cause a 3% drop in crop yield. Modeling indicates that during low flow periods, the instream conductivity limit of 1500 umhos/cm could be exceeded. Therefore, the applicant has committed to limiting mine water dischazge to a rate that does not cause Fish Creek water to exceed 1500 umhos/cm. Lower Trout Creek -The mine does not affect Trout Creek waters above the confluence with Middle Creek, but the flow rate and quality of Trout Creek is affected by site 109 (Portal area) dischazge into Foidel Creek. Foidel Cteek flows into Middle Creek upstream of the confluence of Middle Creek and Trout Creek. Modeling submitted during TR-32 review indicates the potential for significant impact over the lower Trout Creek reach due to mine water dischazges. Conductivity over this reach should not be a problem, as the highest modeled value was 970 umhos/cm, which would not preclude irrigation usage. The sulfate limit of 250 mg/1 over the period of June to February could be exceeded. Therefore, the mine will adjust dischazge levels to prevent exceedance during this period in the same way conductivity levels will be regulated on Lower Fish Creek. The mine demonstrated that sulfate levels could be accurately determined by the existing relationship with conductivity (sulfate/conductivity = 0.32). When conductivity at the upstream site (site 301) equals or exceeds 740 umhos/cm, discharge from site 109 will cease entirely. Lower Trout Creek- Below Fish Creek -Flow rate and water quality will be affected by mine water dischazge from site 115 (Fish Creek borehole) and site 109 (portal dischazge). Modeling performed by the applicant Lh TR-32 indicates that during low flow, the sulfate standard of 250 mg/1 could be exceeded due to mine water dischazges. The applicant has committed to conduct upstream and 12