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Logan Wash Mine Annual Report <br />Permit No.: M- 1977 -424 <br />2.3 Structures <br />2.3.1 Vaults, Pipelines, and Evaporation Pond <br />Structures that remain at the mine site include two vault structures, one on the Lower Bench and <br />one on the Research Mine Bench and a capped and vented ventilation shaft. In addition, the retort <br />water pipeline conveys retort mine water from the sealed L -1 portal at the mine site to the <br />Evaporation Pond, which includes a settling pond and associated detection vault. See Figure 2 for <br />the locations of these structures. The two bench vaults are confined space concrete structures with <br />exposed surface access -ways constructed at grade. These structures will remain as permanent <br />structures on the mine site to manage and monitor mine water drainage. Other subsurface <br />structures at the mine site include the Research Mine drainage pipeline, the L -1 mine water <br />pipeline (discharges non -retort mine water to the surface), and several monitoring wells. <br />Two manholes on the retort water pipeline, the Upper Manhole and Lower Manhole, are accessed <br />periodically to measure pipeline flows. The Upper Manhole is located in the vicinity of the <br />former Heater Treater (Area 15), in the upper part of Logan Wash near the confluence with Dry <br />Gulch. Over time, the area near the Upper Manhole has become buried by stormwater sediment <br />and debris flow materials from the nearby hillslope. In late 2013, the detritus was regraded to <br />provide safe and efficient access to the manhole hatch for retort water discharge monitoring. An <br />area approximately 40 ft long by 20 ft wide (0.018 acres) was regraded and then seeded and <br />mulched. The Lower Manhole is located just north of the Evaporation Pond. Other manholes exist <br />on the retort water pipeline that are buried by shallow road fill, colluvium, and vegetative litter, <br />and have not been accessed in recent years. <br />2.3.2 Wells <br />Wells associated with the Logan Wash Mine were constructed within and outside of the <br />designated permit boundary. Past reconnaissance has been conducted to locate and confirm the <br />existence of these well sites. Eight wells were located and identified within the permit area and <br />within Logan Wash. Of the 8 identified wells, one well, Well LWCW -IA, will remain in place as <br />a compliance well until final permit closure. Well LWCW -lA is sampled for water quality on a <br />semi - annual basis. <br />Wells LW -108, LW -112, and LW -242 were abandoned in 2005 in accordance with Colorado <br />Division of Water Resources rules. The other 4 wells, LW -32, LW -45, LW -116, and LW -22, <br />were scheduled to be abandoned in 2010, but were not. Well LW -45 was re- located during 2012 <br />and will be considered for abandonment along with wells LW -32 and LW -116 depending on final <br />mine closure methods. Well LW -22 may be needed to support permit alternatives for discharge of <br />non -retort mine water. Reconnaissance to date has not revealed any other monitoring wells within <br />the permit area and the Logan Wash drainage. <br />Reconnaissance for wells located outside the permitted area in distant drainages was conducted in <br />past reporting periods. Wells LW -102 and LW -243 were located in Smith Gulch, Well LW -103 <br />was located in Kelly Gulch, and Well LW -104 was located in Riley Gulch. Well LW -121, <br />apparently constructed in Bowdish Gulch, was not located after a thorough search and is assumed <br />abandoned. Table 3 shows the status of well abandonment as of this reporting period. <br />2.4 Status Summary <br />Areas not reclaimed and released by DRMS in the permit include Areas 1, 2, 3, 4, 10, portions of <br />Area 13; Area 23, and the 0.65 acre Soil Barrow Area. Areas l through 4 include the Upper and <br />Western Water & Land, Inc. 3 <br />