PERMFILE137697

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 4/8/2005
• Doc Name: pages 2.05-157 to 2.05-267
• Section_Exhibit Name: 2.05 Operation and Reclamation Part 3
• Media Type: D
• Archive: Yes

Wes/ Etk Mine
from the WWTP goes through sedimentation pond MB-2R prior to discharge to the North
• Fork.
Effects of Subsidence
The effects of subsidence from mining of the B-Seam in the Apache Rocks and Box Canyon
mining areas are discussed in Section 2.05.6 (6)(e)(i). Water quality impacts from subsidence
could potentially result from: (1) increased stream erosion rates due to alteration of channel
slopes and geometry; or (2) cross-connection of previously isolated formations and the surface
hydrologic system.
The amount of subsidence predicted to result from the Apache Rocks and Box Canyon mining
areas is discussed in Section 2.05.6 (6)(b)(i). As discussed previously in this section, the
amount and pattern of change in the channel slope due to subsidence is not of a magnitude to
cause significant channel degradation and erosion (see Exhibit 55). Small adjustments could
occur which would stabilize in a relatively short period of time.
From the standpoint of groundwater quality effects resulting from subsidence, the key
consideration is that groundwater resources which could be disrupted by the proposed mining
are very limited in extent and magnitude. There is no demonstrated formation groundwater
use at the mine nor in the general area. There are no formations in the existing or proposed
permit area that would qualify as "aquifers." As discussed in the Groundwater Quality Effects
• section, if groundwater moves via asubsidence-caused fracture from a higher formation to a
lower formation or into the B or E-Seams, the water quality change will not be significant.
Table 61 Projected Wastewater Plant Discharge
Year Projected Discharge'
p1iGD)
1995 0.02
1996 0.02
Maximwn O.Od
Addirional treatmentcapacity was installed in 1997 to handle through-puts of ?0.000 gpd.
Groundwater Quantit~ffects
This section of the application defines and evaluates the hydrologic consequences related to
groundwater quantity including impacts from construction of mine entries, the direct mining
impacts resulting from single-seam mining (F or B-Seams) in the original permit area, the
eastern panels of the Apache Rocks mining area and the Box Canyon mining area, multi-seam
mining (E and B-Seams) in the western panels of the Apache Rocks mining area, and the
storage of water in previously mined down-dip sealed panels (large capacity sealed sumps).
Groundwater quality effects are discussed in the following section. Readers are encouraged to
• review Sections 2.05.6 (3)(a~), West Elk Mine Experience and Regional Mining Experience,
2.05-2.09 RevisedJw. ! 995 PR06: Revised Nov. / 998 TR80; //98 PR08