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Attachment TP4UGD <br /> Page No.TP4UGD- 1 <br /> Permit No. CO-0044768 <br /> M ne Remediation Plan. Tailings Pond No. 4 Upland <br /> Groundwater Diversion <br /> Remediating Party Sunnvside Gold Corporation <br /> PO Box 177 <br /> Silverton CO 91433 <br /> Contact- Lam Perino <br /> Reclamation Manager <br /> 1. Description of Mining Activities <br /> Physical Description of Conditions <br /> Tailings Pond No. 4 was constructed as a hillside impoundment in an alluvial valley The hillside <br /> contact is glacial till and up-gradient of this contact area are alluvial fans from cliff erosion. Snow- <br /> melt and rainfall that is not lost to evaporation or plant transpiration reports as surface runoff or <br /> infiltrates to flow as groundwater to the streams in the valley floor. A percentage of the infiltrating <br /> water flows as groundwater on the bedrock-subsoil contact especially,where a drainage channel <br /> flows over a bedrock-alluvial fan contact where the infiltration rate could be large <br /> Sunnvside Gold Corporation(SGC)has installed a continuous lined surface runoff interception and <br /> diversion ditch up-gradient from Tailings Pond No. 4. This ditch is effective in diverting upland <br /> surface runoff water around the deposited tailings. SGC has also constructed a groundwater cutoff <br /> wall along approximately 400 feet of the hillside contact„here seeps and springs were indicative that <br /> bedrock contact was close to surface and subsurface water existed in this area in the spring This <br /> cutoff wall was constructed of compacted and/or poured concrete starting at the bedrock contact and <br /> rising to an elevation that allows pipes to drain any intercepted groundwater into the lined surface <br /> diN ersion ditch and around the tailings <br /> Based on topograph% and up-gradient springs that are currently diverted around the tailings by the <br /> surface water diversion ditch in areas not covered by the existing groundwater cutoff wall. it is <br /> possible that additional long term benefits to water quality could be realized by extending the cutoff <br /> wall <br /> General Description of the Project Site <br /> The Tailmg's Pond No 4 Upland Groundwater Diversion Project site is located on the hillside <br /> directh abo\e Tailings Pond No 4 The site is 0.25 miles northeast of the Silverton town limit on <br /> Colorado High\\a\ 110 See attached location map. <br />