2014-10-01_REPORT - C1982056

• Permit No: C1982056
• IBM Index Class Name: Report
• Doc Date: 10/1/2014
• From: DRMS
• To: Twentymile Coal Company
• Annual Report Year: 2013
• Permit Index Doc Type: Hydrology Report
• Email Name: JDM
• Email Name: DIH
• Media Type: D
• Archive: No

within and adjacent to
mining has not impaired the use of groundwater from the
the permit area
Trout Creek Sandstone in the permit area, with water levels
and quality remaining stable in 2013.
Based on the information presented in the 2013 AHR the
23. Prevention of
disturbance to the hydrologic balance within and adjacent to
material damage to the
CDRMS regulation
the permit area caused by mining and reclamation at the
hydrologic balance
4.05.1(1)
Foidel Creek Mine is the minimum that can be expected
outside the permit area
from an underground mining operation at this location. Use
of best management practices indicates minimization of
disturbance to the hydrologic balance.
Surface water— Mine pumping into Fish Creek at site 115
had ceased in mid -2006, and was reactivated in 2008. In
2013, no discharge was conducted at Sites 115 or 109.
Discharge at 10RT was initiated in early September 2008 due
to a rise in water levels within sealed mine areas. During
discharge, downstream water samples were collected to
verify potential impacts. Samples were collected at Trout
Creek (Site 1005) downstream of confluences from Fish
24. Agreement of
CDRMS regulation
Creek and Foidel Creek. Subsequent water quality data from
observed hydrologic
"probable
2.05.6(3) and
10RT raw effluent indicated exceedances for FeTR and WET
impacts with
requirement to keep
tests. TC discontinued discharge at 10RT in early 2009 and
hydrologic
current CDRMS
pumped directly to the area No. 1 Pit impoundment. No
consequences"
regulation 2.03.3(1)
exceedances were observed at the No.1 Pit discharge,
projected in mining
Outfall 005A in 2013.
Ground water — No material damage has occurred, as
discussed in item 21, above. However, the ground water
point of compliance well for the Trout Creek alluvium, 008 -
AT-1, was identified as being destroyed in November of
2012. As such, no data has been collected for the Trout
Creek alluvium since April of 2012. A determination of
compliance since April 2012 cannot be made due to a failure
to collect and submit the required data.
25. Adequacy of
CDRMS regulation
ground water
4.05.13(1)
monitoring program
26. Adequacy of
CDRMS regulation
The current ground water monitoring program continues to
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