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Annual Report — 2014 <br />Henderson Mine and Mill Reclamation Activities <br />Permit No. M- 1977 -342 <br />2.3.3 —Flood Storage Capacity <br />Analysis of flood storage capacity in the Mill tailings impoundment was carried out by W.W. Wheeler, <br />per DRMS requirements stipulated for Technical Revision (TR) 14. This analysis is included as <br />Attachment B. <br />2.3.4 — 3 -Darn Seepwater Line Leak -Down Test <br />The annual 3 -Dam seepwater line leak -down test for 2014, per DRMS requirements stipulated for TR -09, <br />was completed on June 10'. The seepwater lines held static pressures over a 24 -hour period, as designed. <br />See test report in Attachment C. <br />2.3.5 — Hydrogeologic Investigations <br />Henderson completed Phase I of the Ute Park Extraction Wellfield downgradient of 1 -Dam, including the <br />installation of one extraction well (MLEX -1) and two monitoring wells, per Technical Revision 23. As- <br />built drawings and engineer certifications are being prepared and will be submitted to the DRMS when <br />they are complete. Phase II is planned for 2015, with the installation of two additional extraction wells <br />and two monitoring wells. <br />Henderson submitted the 5- Quarter Water Quality Data and Baseline Parameters Report as required in the <br />Water Management Plan, as well as an assessment of low pH measurements at the MLGW -7 Point of <br />Compliance (POC) well. <br />As a result of low pH measurements in the Mine POC monitoring well MNGW -1, Henderson installed <br />two additional monitoring wells downgradient of the mine facilities to investigate the source of low pH <br />waters and the adequacy of the existing POC location and well construction. A well installation summary <br />report will be submitted to DRMS in early 2015, followed by a water quality assessment once sufficient <br />data is available. <br />2.3.6 — Gravel Pit Operations <br />No aggregate material was crushed and screened in 2014. Approximately 50,000 tons of material is <br />anticipated to be produced in 2015. <br />2.3.7 Tailing Delivery Line <br />Henderson Mill underwent a refurbishment project in 2014, whereby all pre - existing structural steel on <br />the Tailing Delivery Line was replaced by a system of more robust I -beam and concrete footer <br />construction. In addition to this activity, all drop towers existing below drop tower 12 were removed and <br />replaced with HDPE pipe. This pipe replaced reinforced concrete pipe with heavy -wall HDPE down to <br />the No. 1 Cutout structure. An as -built drawing set and Engineer's Certification will be remitted to the <br />State once they are completed. <br />Page 3 <br />