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Logan Wash Mine Annual Report
<br />Permit No.: M-1977-424
<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. Two
<br />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. 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. Wells LW-108, LW-112, and LW-242 were
<br />abandoned in 2005 in accordance with Colorado Division of Water Resources rules. The other 4
<br />wells, LW-32, LW-45, LW-116, and LW-22, were scheduled to be abandoned in 2010, but were
<br />not. Well LW-45 has been destroyed or buried by oil and gas road construction activity. An effort
<br />to locate the well with a metal detector failed. Well LW-22 may be needed to support permit
<br />alternatives for discharge of non-retort mine water. Abandonment of wells LW-32 and LW-116 is
<br />planned for 2011. Reconnaissance to date has not revealed any other monitoring wells within the
<br />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, has not been field located because of access issues.
<br />Table 3 shows the status of well abandonment as of this reporting period.
<br />2.4 Status Summary
<br />Areas not reclaimed in the permit include Areas 1, 2, 3, 4, 10, portions of Area 13; Area 23, and
<br />the 0.65 acre Soil Barrow Area. Areas 1 through 4 include the Upper and Lower Mine Dumps
<br />(face areas), Upper Mine Bench, Lower Mine Bench, and the Research Mine Bench and Dump,
<br />respectively. Area 10 is the former Helo Pad. Area 13 is Miscellaneous Access Roads. Area 23 is
<br />the Evaporation Pond and Pipeline. According to the 1985 annual report, the original disturbed
<br />acreage of Area 23 was 14.87 acres, 5.07 acres of which was reclaimed before 1985, leaving 9.8
<br />acres remaining to be reclaimed.
<br />Area 13, Miscellaneous Access Roads (Table 2), includes a number of older roads that have been
<br />reclaimed. In this report, the Mine Bench and Portal roads referred to in Table 2, consist of the
<br />Lower Access Road (1.0 acres), Upper Access Road (5.3 acres), Upper Bench Road (1.4 acres not
<br />including bench), and Lower Bench Road (0.9 acres not including bench). Area 1, the Upper and
<br />Lower Mine Dump faces (12.36 acres) were revegetated during 2003-2005. Area 2, the Upper
<br />Mine Bench (0.74 acres) was revegetated in 2004 and 2005. Area 4, the Research Mine Bench
<br />(2.75 acres) and Dump (1.51 acres), Area 10, the former Helo Pad (0.24 acres), and the Upper
<br />Western Water & Land, Inc. 3
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