2014-02-03_REPORT - C1981028

• Permit No: C1981028
• IBM Index Class Name: REPORT
• Doc Date: 2/3/2014
• Doc Name: 2012 Annual Hydrology Report Review
• From: DRMS
• To: Coors Energy Company
• Annual Report Year: 2012
• Permit Index Doc Type: Hydrology Report
• Email Name: JLE
• Email Name: SB1
• Media Type: D
• Archive: No

Requirement
Requirement
citation
Reviewed
Comment
Each pit disrupts the potentiometric surface. After final
S. Restoration of
backfilling, the pits can be expected to show full recovery
ground water
CDRMS
of the potentiometric surface outside of the pits and water
recharge to
regulation
yes
table (unconfined) conditions inside the pits. No
approximate
4.05.11(3)
significant formation of surface spoil springs is expected
due to the flat topography; therefore, there will be no loss
premixing rate
of ground water flows to surface waters.
The Probable Hydrologic Consequences section of the
T. Prevention of
permit application predicts no appreciable impacts to
adverse impacts
CDRMS
ground water systems outside the permit area. Water
to ground water
regulation
yes
quality data from well DH -96 indicate there have been no
systems outside
4.05.11
adverse impacts to ground water in the Ennis alluvium and
the permit area
eolian sand outside the permit area, several thousand feet
downgradient from the mines pits.
The approved post- mining land use of most of the permit
U. Prevention of
area is rangeland (a few acres are approved for
impacts to ground
commercial /industrial gas well use). As previously
water that
CDRMS
discussed, ground water in the Ennis alluvium and eolian
adversely i mpact
regulations
yes
sand have not been adversely impacted by mining and
the s mining
4.05.1(2) and
reclamation operations at the Keenesburg Mine. Ground
land use e within
u
4.05.11
water in the Laramie coal and sandstone is not likely to have
the permit area
had adverse impacts as explained in the previous discussion
of Basic Standards for Ground Water.
V. Minimization of
disturbance to the
hydrologic
CDRMS
Changes to the hydrologic balance within and adjacent to the
balance within
regulation
yes
permit area, if any, would be the minimum that can be
and adjacent to
4.05.1(1)
expected 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
CDRMS
The Probable Hydrologic Consequences section of the
X. Agreement of
regulation
permit application predicts no appreciable impacts to the
observed
2.05.6(2) and
hydrologic balance. Monitoring data in the hydrology
hydrologic
requirement
report confirms this prediction. No impacts to ground
impacts with
"probable
to keep
water have been found in downgradient alluvial /eolian
information
yes
sand monitoring well, DH -96. Should degradation of
hydrologic
ground water by leachate immediately adjacent to pits
consequences"
current,
CDRMS
occur, it would be a minor impact. No adverse impacts to
(PHC) projected
regulation
surface water quality have been found at the Keenesburg
in mining permit
2.01.1(1)
Mine.
Y. Adequacy of
CDRMS
ground water
regulation
yes
monitoring
4.05.13(1)
program
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