2016-02-08_REVISION - C1996083

• Permit No: C1996083
• IBM Index Class Name: Revision
• Doc Date: 2/8/2016
• Doc Name: Adequacy Response
• From: J.E. Stover & Associates, Inc
• To: DRMS
• Type & Sequence: TR99
• Email Name: JDM
• Email Name: DIH
• Media Type: D
• Archive: No

Hole (Interburden)
Mudstone
Sandy
Mudstone
Shale
Sandstone
Coal
Lost
Core
TC -03-03 (74.5)
23.0
28.3
4.0
19.2
0.0
CWI-DH-50 (70.6)
31.7
17.7
10.0
8.0
3.2
CWI-DH-51 (70.0)
16.2 1
47.1
0.0
6.7
0.0
CWI-DH-62 (105)
9.0
60.0
1 15.5
20.5
0.0
SS -9 (80.3)
26.4
28.8
14.9
10.2
0.0
SS -2(190)
7.5
52.0
65.5
40.0
25.0
0.0
Maps 08 and 08A present lithologic logs that show the hydraulic isolation of the
Rollins Sandstone.
The perched water below the D -Seam and above the B -Seam is or was monitored
by drill holes DH -58a and DH-67-Blw. A new DH-67-B1w was drilled in September
2014 and shows the most consistent data. For the period of record from September
2014 through December 2015 for DH-67-Blw, the average field conductivity was
5,773 umhos/cm with a range of 4,800 to 6,300 umhos/cm, the average field ph was
8.3 with a range of 7.9 to 8.5, average total iron was 1.055 mg/I with a range of
0.595 to 1.37 mg/I and average total manganese was 0.0606 mg/I with a range of
0.0271 to 0.1040 mg/I.
The perched water above the D -Seam is or was monitored by drill holes DH -58, 66,
and DH-67-Abv. DH-67-Abv shows the most consistent data. By eliminating some
early monitoring data, the quality of water in this perched water bearing zone, as
reported in the 2013 AHR show pH in the range of 7.1 to 7.9, conductivity ranges
from 2000 to 3700 umhos/cm and total recoverable iron ranges from 0.046 to 1.82
mg/I and total recoverable manganese ranges from 0.006 to 0.05 mg/I for the period
June 2005 to November 2013. Based on the quality of the mine water discussed
above, mine water seepage into the perched water above the D -Seam would
improve the water quality in the upper perched water bearing zone.
In the western mining district, west of Terror Creek, the perched water above the 13 -
Seam is monitored at monitoring well 2010-1 SS. The monitoring data forwell 2010-
1 SS suggests that the well was initially contaminated during construction, but has
since reached an equilibrium state from which future changes may be observed.
For the period of record from March 2015 through October 2015 for 2010-1 SS, the
average field conductivity was 1,384 umhos/cm with a range of 1,330 to 1,420
umhos/cm, the average field ph was 7.1 with a range of 7.0 to 7.2, average total iron
was 3.35 mg/I with a range of 2.47 to 4.94 mg/I and average total manganese was
0.116 mg/I with a range of 0.095 to 0.145 mg/I.
The Applicant worked over the active monitoring wells during 2014 so more
consistent data is available.
TR -99 2.05-123 02/16