2017-04-14_REPORT - M1977004

• Permit No: M1977004
• IBM Index Class Name: REPORT
• Doc Date: 4/14/2017
• Doc Name: Annual Fee/Report/Map
• From: Barrick Gold
• To: DRMS
• Annual Report Year: 2017
• Email Name: DMC
• Media Type: D
• Archive: No

Pitch Reclamation Project Colorado Mined Land Reclamation Board—2016 Annual Reclamation Report
recommended for 2015. However, due to equipment failure while performing the task, coupled
with early snowfall,the task was delayed until 2016 as detailed below., Two additional monitoring
points were added in 2015.
As discussed in Section 3.5, the tension cracks in the South Mine area were graded closed in 2016 to
improve drainage. Positive drainage was re-established on the benches and a lower bench was added to
the slope. These maintenance measures will be continued as needed to optimize drainage from the area
of slope displacement.
Surveys of the accessible monuments were conducted for the current monitoring period on August 25,2015
and August 22, 2016. Because the surveys are conducted over several consecutive days,the median date
(September 1, 2016)was used to represent the data for 2016. Of the 90 currently viable monitoring points
in the North Pit and South Mine Area, 44 had annual displacement magnitudes that were greater than
survey error during the 2015 to 2016 monitoring period, as shown on the summary table and figure
presented in Appendix A. By comparison, 29 points had annual displacement magnitudes greater than
survey error for the 2013 to 2014 monitoring period. Monitoring points where displacement was not
detected,or was less than calculated survey error,are indicated as"ND"or non-detectable in Appendix A.
The survey data for the most recent monitoring period indicated minor slope displacement in the northeast
corner of the North Pit and the south wall of the North Pit. Displacement at the south wall of the North Pit
ranged from 0.03 ft to 0.25 ft at 13 monitoring points. Displacement at the northeast corner of the North Pit
ranged from 0.04 ft to 0.32 ft at 21 monitoring points. At the east wall of the South Mine area,displacement
during the 2015 to 2016 monitoring period ranged from 0.02 ft to 8.22 ft at 10 monitoring points. As
previously stated, heavy and sustained rainfall during late spring 2015 is suspected to have contributed to
this increased slope displacement. At two monitoring points located in a peat bog above the North Wall of
the North Pit, slope displacement of 0.20 ft and 0.19 ft was indicated.
In the 2015 to 2016 monitoring season there were 34 survey points in the North Pit slopes that had
displacements greater than potential survey error, including: MP-12, MP-18, MP-23, MP-24, MP-28, MP-
29, MP-34, MP-35, MP-36, MP-37, MP-38, MP-39, MP-40, MP-43, MP-59, MP-66, MP-68, MP-69, MP-72,
MP-74, MP-75, MP-77, MP-78, MP-79, MP-80, MP-85, MP-86, MP-87, C-94-1, 194-02, 198-01, 198-02, P-
04 and P-08. There were 10 monitoring points at the east wall of the South Mine area that had
displacements greater than survey error, including: HS-4, P-05, MP-HSR, MP-S7, MP-S8, MP-S9, MP-63,
S-1, MP-92, and MP-93.
The current maximum displacement at the east wall of the North Pit is 0.32 ft at MP-66, compared to 0.41
ft at MP-18 during the previous monitoring period. The current maximum displacement at the east wall of
the South Mine area is 8.22 ft at MP-93, compared to 3.29 ft at MP-93 during the previous monitoring
period. Slope displacement at the east well of the South Mine area was localized with respect to
displacement near MP-93 and there has been no damage to the regrading work that was done in 2016.
The displacement at the east wall of the South Mine area does not represent a risk to personnel due to the
creep style of movement and the presence of a catch bench below the feature. This area should be
monitored and visually assessed in 2017. Grading work will be undertaken if needed to promote positive
drainage or bench repair is needed.
4.2 Inclinometer Evaluation
Three slope inclinometers were installed in 1998 to monitor areas of the North Pit. Annual survey data has
been collected since July, 2003. As shown on Figure 4 and Appendix A, two slope inclinometers (198-1
and 198-2)are located on the south wall of the North Pit and the other(198-3) is above the crest of the east
wall of the North Pit. The monitoring period is July 25, 2015 to September 18, 2016. Results from the
inclinometer surveys indicate that minor slope displacement was recorded at 198-1 during the monitoring
period, and no displacement was indicated at 198-2 and 198-3.
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