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compliance during that time cannot be made due to a failure to collect and submit the data. <br />Monitoring well 008 -AT -1 was reestablished in the summer of 2014 and monthly water <br />monitoring has been ongoing since the reestablishment of the well. No problems have been <br />identified. <br />Surface water <br />Several possible effects on the surface water system have been identified: <br />Discharge of mine inflow water to surface water drainages <br />Mine water discharged to the surface system will increase the conductivity, total dissolved <br />solids (TDS), and sulfate and iron concentrations in the streams receiving the discharge. <br />Total suspended solids, sodium adsorption ratio (SAR), and pH could also increase due to <br />these discharges. SAR may reach up to 6.2 in Fish Creek and 3.0 in Trout Creek. Sulfate <br />and conductivity impacts are predicted for various segments of the stream system to be <br />affected. TR -32 approved a plan which will allow the mine to discharge considerable <br />volumes of degraded water during high flow (high dilution capacity) and lesser or no <br />discharge during periods of low flow (minimal dilution capacity). <br />Lower Middle Creek — Impacts in lower Middle Creek from the confluence with Foidel <br />Creek to the confluence with Trout Creek will be pronounced due to relatively small <br />instream flows. There is no sulfate or irrigation standard over this reach. However, due <br />to standards on Trout Creek immediately below this segment, impacts will be minimized <br />during most times of the year. <br />Lower Fish Creek — The potential for significant impacts to lower Fish Creek, from mine <br />water discharge site 115 (Fish Creek dewatering facility) downstream to the confluence <br />of Fish Creek with Trout Creek, exists. Although no sulfate standard applies over this <br />reach, Fish Creek and adjacent alluvial valley floor areas are held to a 1500 umhos/cm <br />material damage standard for irrigation waters. Modeling indicates that during low flow <br />periods, the instream conductivity limit of 1500 umhos/cm could be exceeded. <br />Therefore, the applicant has committed to maintain its mine water discharge rate from <br />site 115 at a level which would prevent material damage (<1500 umhos/cm) by <br />measuring upstream flow and quality and computing a discharge rate which would <br />prevent downstream exceedance of the conductivity limit for irrigation waters. The <br />sulfate standard for drinking water of 250 mg/1 does not apply over this reach. <br />Lower Trout Creek — The mine does not affect Trout Creek waters above the confluence <br />of Trout Creek with Middle Creek, but the flow rate and quality of Trout Creek is <br />affected by site 109 (portal area) discharge into Foidel Creek. Foidel Creek flows into <br />Middle Creek upstream of the confluence of Middle Creek and Trout Creek. Modeling <br />submitted during the TR -32 review indicates the potential for significant impact over <br />lower Trout Creek from the confluence with Middle Creek to the confluence with Fish <br />Creek due to mine water discharges. Conductivity over this reach should not be a <br />problem, as the highest modeled value was 970 umhos/cm, which would not preclude <br />irrigation usage. The sulfate limit of 250 mg/l over the period of June to February could <br />Foidel Creek Mine 22 February 25, 2016 <br />