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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 />2014, and 2015 and 2016 data indicate no lingering effects from the pumping. The boreholes <br />were sealed in 2015. The road and pad for these holes were reclaimed and seeded in 2016. <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. <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 />water discharge (CDPS discharge point 011) commingled with upper Sanborn Creek flow for a <br />distance of approximately 300 feet through culverts under the railroad and highway prior to <br />discharging into the North Fork of the Gunnison River. The S-2 sample site is located at the <br />outlet of the culvert, prior to the confluence with the river. Because of the 2003 closure of the <br />Sanborn Creek mine, and the termination of discharge Outfall point 011, the S-2 sample site was <br />no longer needed and, thus, eliminated from the OMLLC hydrologic monitoring program in <br />2004. (see TR -45). <br />Sanborn Creek, an ephemeral stream, flows at monitoring point S-1 during spring runoff and <br />significant precipitation events. During 2016, S-1 had the usual minimal flows and by mid-June <br />flows had ceased altogether. An analysis of the limited data shows somewhat elevated <br />1 <br />