2018-04-17_REPORT - C1982057

• Permit No: C1982057
• IBM Index Class Name: Report
• Doc Date: 4/17/2018
• Doc Name: Annual Reclamation Report
• From: Twentymile Coal, LLC
• To: DRMS
• Annual Report Year: 2017
• Permit Index Doc Type: Annual Reclamation Report
• Email Name: RAR
• Media Type: D
• Archive: No

CHRONOLOGICAL HISTORY OF REVEGETATION & BOND RELEASE
As of 2017, all disturbed areas not deemed permanent have
been seeded. Total areas seeded and revegetated prior to 2017
are shown on 2012 annual reclamation report Chronological
Seeding Map. SP submitted SL -5 requesting Phase II bond
release on eligible areas, which was approved on approximately
798 acres (as shown in Figure 2) on 08/27/14. SP completed
revegetation success monitoring for Phase III bond release
during 2015 - 2016. The results of this monitoring effort are
being incorporated into a draft bond release submittal package
to be submitted during second quarter 2018. SP also submitted
a request for bond reduction in December 2016, which was
subsequently approved on July 24, 2017.
SEDIMENTATION POND SURVEYS
SP monitors sedimentation ponds for sediment storage
capacities. Up through 2015, this monitoring was conducted
by physically surveying each pond each year. This schedule
provided a sediment yield history and gave advanced warning
to operations personnel when sediment clean-out work was
needed. Also, SP visually inspects each pond, at a minimum,
quarterly each year. During these inspections, any significant
observed change in sediment storage or noticeable expansion
of the sediment delta at the inlet to the pond are noted as
conditions requiring pond maintenance.
t
Figure 1: Phase II Bond Release Area (798
Because the mined areas have been reclaimed and revegetated for acres)
several years, the available storage capacities typically do not
change significantly from year to year, so a request was submitted and approved to monitor sediment
accumulations on a 5 -year schedule for ponds that flow year-round and to visually inspect any other ponds.
The results of the 2014 annual survey indicated that all ponds are above the minimum requirement for storage
as summarized by Table 13.3, Sediment Pond Capacities.
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TABLE 13.3 SENECA SEDIMENT PONDS - WATER CAPACITY TRENDS
YEAR
2008
2009
2010
2011
2012
2013
2014
005
1.8
Z.
4.9
4.9
4-
4
3.3
TR -59
II -W - 006
4.44
4.8
33
53
5.3
5.3
5.3
5.9
2120/2004
II -W - 009
4.35
7,2
-.3
7.3
6.6
6.6
-
6.8
"/10/1992
II -W - 013
2.41
2.8
2.9
3
2.8
2.9
-
2.6
3/24/2000
II -W - 016
2.804
33
3.7
3.9
3.8
3.8
-
3.3
TR -73 6/11
II -W - 017
1.68
3.6
3.6
3.4
4.8
4.-
3.1
8/1/2003
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(2) R•m Krxg cgtaitti Ft�irixralt�i}!Sr?t or orifnt