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E-1- Lower Elk Creek <br />Surface water monitoring point E-1 - Lower Elk Creek, an ephemeral drainage, is monitored as a <br />down gradient site to verify that the Elk Creek Mine and the surface facility located at Somerset <br />does not have an adverse effect on the quality of runoff in the drainage. During spring <br />snowmelt, elevated levels of TSS and Total Recovered Iron are routinely encountered, <br />presumably from natural upstream erosion in the unstable Elk Creek drainage, until stream flows <br />subside. Naturally occurring slide blocks exist in the Elk Creek headwaters and no doubt <br />contribute additional sediment loading. <br />Of particular note are the possible lingering effects of pumping the two mine recovery boreholes <br />#1 and #2 during 3 months in 2013. Elevated levels of TDS from naturally occurring alkalinity <br />were noted in the E-1 sampling during 2013. The additional pumping flows extended the 2013 <br />runoff period in Elk Creek. Elevated dissolved solids raised conductivity measurement during <br />pumping, but quickly returned to "normal" after pumping was terminated on September 9, 2013. <br />Data beyond 2014 indicate no lingering effects from the pumping. The boreholes were sealed in <br />2015. The road and pad for these holes were reclaimed and seeded in 2016. <br />Mine activities in 2017 included reclamation of drill hole pads and roads above the Elk Creek <br />drainage. This minimal activity should not have impacted the creek, but chloride levels appear <br />to be elevated for both E-1 Lower Elk Creek and for E-2 Upper Elk Creek in 2017. E-2 chloride <br />levels which is upstream of actual mine facilities were higher than the E-1 levels downstream of <br />the mine facilities. <br />An analysis of the data suggests there is no adverse impact of the Elk Creek Mine to Lower Elk <br />Creek. <br />E-2- Upper Elk Creek <br />Surface water monitoring point E-2 - Upper Elk Creek, an ephemeral drainage, is monitored to <br />verify that the Elk Creek mine does not have an adverse effect on the quality of runoff in the <br />drainage. In addition, the site will serve as an up -gradient site to monitor Elk Creek prior to <br />entering the OMLLC surface facility. See the above comments for site E-1 for the discussion on <br />the dewater recovery boreholes. <br />An elevated September 2014 and July 2015 chloride levels appear to be anomalies, as the down <br />dip site does not show a similar chloride level. An analysis of the data suggests there is no <br />adverse impact of the Elk Creek Mine to Upper the upper Elk Creek site or this segment of <br />Lower Elk Creek in particular. See above in E-1 for discussion on 2017 chloride levels. <br />S-1 — Upper Sanborn Creek and S-2 — Lower Sanborn Creek <br />Surface water monitoring points S-1 - Upper Sanborn Creek and S-2 — Lower Sanborn Creek <br />were established to monitor the flow in ephemeral Sanborn Creek above and below the disturbed <br />area of the Sanborn Creek Mine site. Historically, Sanborn Creek also received mine water <br />discharge from the Sanborn Creek Mine, consisting primarily of natural mine water inflows and <br />some runoff of imported (from the North Fork intake) water from the mining sections. The mine <br />W <br />