2014-06-13_REPORT - C1981028

• Permit No: C1981028
• IBM Index Class Name: Report
• Doc Date: 6/13/2014
• From: DRMS
• To: Coorsd Energy Company
• Annual Report Year: 2013
• Permit Index Doc Type: Hydrology Report
• Email Name: JLE
• Email Name: SB1
• Media Type: D
• Archive: No

Requirement
Requirement
citation
Reviewed
Comment
The approved post - mining land use of most of the permit
area is rangeland (a few acres are approved for
commercial /industrial gas well use). As previously
discussed, ground water in the Ennis alluvium and eolian
sand have not been adversely impacted by mining and
reclamation operations at the Keenesburg Mine. According
to section 2.04.7; page 50 of the permit, water is not likely
used from the Laramie shale or coal aquifers due to its poor
quality.
Three monitoring wells are located within the permit area.
Well AMW -1, north of the B -Pit is completed in undisturbed
overburden. Well SMW -2, located east of B -Pit is
U. Prevention of
completed in reclaimed spoils. Well AMW -2, located north
impacts to ground
CDRMS
of A -Pit is completed in reclaimed spoils. According to
water that
regulations
Appendix I of the permit, the pre -mine overburden aquifer
adversely impact
4.05.1 and
yes
water quality was very poor and not acceptable for many
the postmining
4.05.11
1
uses. The Division compared the groundwater data supplied
land use within
for these wells to the groundwater data for pre -mine
the permit area
overburden well 172. The water quality results reported in
the baseline data for pre -mine overburden well 172 have
sulfate, boron, iron, lead and manganese levels higher than
the groundwater standards for domestic use. Many
constituent levels in the pre -mine overburden wells are
higher than wells AMW -1, SMW -2 and AMW -2 with the
exception of manganese in well AMW -2. For well AMW -1,
sulfate levels were reported to be 480 mg/1 and 440 mg /l
which is higher than the Table 2. Standard for domestic
water use. For well SMW -2, magnesium, manganese,
sodium, SAR and sulfate levels were above the baseline
levels for this well. For well AMW -2, manganese levels
were higher than baseline data for well 172.
V. Minimization of
disturbance to the
hydrologic
CDRMS
Changes to the hydrologic balance within and adjacent to the
balance within
regulation
yes
permit area, appear to be the minimum that can be expected
and adjacent to
4.05.1(1)
from a surface coal mining operation.
the permit area
W. Prevention of
material damage
CDRMS
Previously discussed monitoring data and ground water
to the hydrologic
regulation
yes
quality predictions indicate material damage has been
balance outside
4.05.1(1)
prevented.
the permit area
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