REP15171

• Permit No: C1980007A
• IBM Index Class Name: Report
• Doc Date: 3/28/2006
• Doc Name: 2004 AHR Review Letter
• From: Mountain Coal Company, LLC
• To: DRMS
• Annual Report Year: 2004
• Permit Index Doc Type: Hydrology Report
• Media Type: D
• Archive: Yes

Require-
Require- men{
Requirement ment complied Comment
citation with ? (yes
/no
Pages 2.05-]38 through 166 of the permit application predict the
following probable hydrologic consequences from mining at the
West Elk Mine:
I) Mining will not directly afFect the Rollins Sandstone in the
permit azea (page 2.05-143).
2) Subsidence fractures will not cause significant changes in
water chemistry due to inter-strata) mixing of ground water
V. Agreement CDMG (page 2.05-146).
of observed regulation 3) Mining will not significantly impact the North Fork of the
hydrologic 2.05.6(2) Gunnison River (page 2.05-146).
impacts with and 4) Mining will not preclude any uses of North Fork water (page
"probable requireme 2.05-146).
5) Mining in the Apache Rocks permit revision area will not
hydrologic
conse
uences nt to keep
informatio yes measurably impact the surface water hydrologic balance of
q
" (PHC) n current the Dry Fork of Minnesota Creek (page 2.05-156).
projected in ,
CDMG 6) Mining in the Box Canyon permit revision azea will not
minin regulation measurably impact the surface water hydrologic balance of
g the North Fork of the Gunnison River (page 2.05-156).
permit 2.03.3(1) 7) Mining will not directly impact surface water in Sylvester
Gulch (page 2.05-156).
8) Mining will not significantly impact streams (page 2.05-156).
Review of the 2004 AHR found that impacts have not exceeded
the impacts predicted in the PHC.
W. Adequacy Existing monitoring appears adequate. Bedrock ground water
of ground CDMG monitoring wells are positioned to intercept leachate flow at the
water regulation es two locations most likely to be in the leachate flow path, should
monitoring 4.05.13(1) y leachate migrate down-gradient from the mine workings after
they are flooded. Alluvia{ monitoring wells are properly located
program for assessin im acts to the North Fork of the Gunnison.
Existing monitoring appears adequate. Instream monitoring is
X. Adequacy of conducted upstream and downstream from the mining operation
'
surface water CDMG on the North Fork of the Gunnison River. The mine
s discharges
regulation yes to the North Fork aze monitored at NPDES outfalls. The need
monitoring 4.05.13(2) for new monitoring stations in the South of Divide Area is
program
currently being evaluated in the review of Permit Revision PR-
10.
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