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Page 4 October 14, 2020 <br /> The Retort Water Pipeline was constructed with manhole clean-outs located from approximately 1,200 to 3,700 <br /> feet along Logan Wash Road; two manholes, the Upper Manhole (ME-15) and Lower Manhole (MH-2), are <br /> accessed periodically to measure retort water discharge rates. The Upper Manhole is located in the vicinity of <br /> the former Heater Treater(Area 15),in the upper part of Logan Wash near the confluence with Dry Gulch.The <br /> Lower Manhole is located immediately north of the Evaporation Pond, approximately 40 feet from the pond <br /> gate.Along the Evaporation Pond access road,the Retort Water Pipeline manholes are closer together;a few of <br /> these manholes and the Lower Manhole are accessed semi-annually to clean out any sludge and sediment that <br /> may have accumulated. Most of the manholes on the Retort Water Pipeline are located on the edge of Logan <br /> Wash Road and buried by shallow road fill and colluvium;and have not been accessed in recent years. <br /> According to the 1985 annual report, the Evaporation Pond and Pipeline (Retort Water Pipeline) (Area 23) <br /> consisted of a disturbed acreage of 14.9 acres, 5.1 acres of which was reclaimed before 1985,leaving 9.8 acres <br /> remaining to be reclaimed. The pond was not formally added to the permit until 2008 and is still being used to <br /> manage mine water discharge; reclamation of the pond will occur at some lime in the future. It is assumed that <br /> the portion of Area 23 that has been reclaimed is limited to the ground surface above the buried and active <br /> Retort Water Pipeline(this is assumed to be the 5.1 acre surface overlying the pipeline).The remaining 9.8 acres <br /> closely approximates the actual acreage occupied by the Evaporation Pond. Most of the buried Retort Water <br /> Pipeline underlies the edge of the Logan Wash Road (Area 18), which will not be reclaimed. During final <br /> reclamation of the Retort Water Pipeline,the manhole covers will be removed and the manholes backfilled with <br /> cement,aggregate,and soil and compacted to the ground surface. <br /> All of the described structures are necessary to convey and monitor mine water discharge. The structures will <br /> remain in place indefinitely and will not be reclaimed in the near future.OOSI requests the formal release of the <br /> 5.1 acres initially associated with the Evaporation Pond and Retort Water Pipeline. <br /> 1.4.2 Monitoring Wells <br /> Monitoring wells associated with the Logan Wash Mine were constructed within and outside of the immediate <br /> mine area.Past reconnaissance has been conducted to locate and confirm the existence of these well sites.Eight <br /> wells were located and identified within the mine area and within Logan Wash. Several other wells were located <br /> at some distance from the mine(see Figure 4 and Table 3).Of the 8 identified wells in the mine area,two wells, <br /> Well LWCW-IA and Well LW-22A,will remain in place as monitoring wells until final permit closure. Well <br /> LWCW-IA and LW-22A have been sampled for water quality on a semi-annual basis;recently well LW-22A <br /> has been dropped from the monitoring program,as it had been a voluntary monitoring location. <br /> Wells LW-108,LW-112,and LW-242 were abandoned in 2005 in accordance with Colorado Division of Water <br /> Resources rules. The other 3 wells, LW-32, LW-45, and LW-116,remain in place in the case they may be of <br /> value in the evaluation of mine closure investigations; they will be plugged and abandoned at a later date. <br /> Reconnaissance to date has not revealed any other monitoring wells within the permit area and the Logan Wash <br /> drainage. <br /> Reconnaissance for wells located outside the permitted area in distant drainages was conducted in past reporting <br /> periods. Wells LW-102 and LW-243 were located in Smith Gulch, Well LW-103 was located in Kelly Gulch, <br /> and Well LW-104 was located in Riley Gulch. Well LW-121, apparently constructed in Bowdish Gulch,was <br /> not located after a thorough search and is assumed abandoned. Wells LW-102, LW-104 and LW-243 were <br /> abandoned in 2007. Well LW-103 is located on private land and will likely be transferred to the land owner. <br /> Table 3 shows the current status of well abandonment. <br /> The BLM recently relinquished all monitoring well sites located on federal lands that were associated with the <br /> mine in May, 2017. Wells LW-32, LW-45, and LW-116, located on Fee lands, will be abandoned on a later <br /> date.OOSI will submit a separate release request for monitoring wells in the future. <br /> AYeldell_10142020.docx <br />