NI43-101Pre-Feasibility Study Report - page 568

Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 PFS Technical Report
October 9
th
, 2014
10135-200-46 - Rev. 0
26-2
on the specific areas rock types, the distribution within the mine, and on the
upgrade potential of various rock types.
26.1.2 Update the Pit Slope Stability Evaluation of the Bull Hill & Whitetail Ridge
Open Pits
The current design recommendations for pit slopes are based on limited
hydrogeological information of the pit area and limited geo-mechanical
information. An additional groundwater modeling data study of the pit area has
been completed and the pit slope stability evaluation should be updated to
incorporate a new drilling and strength testing program. The ultimate pit design
developed for the PFS will be used as the starting point for the slope stability
update study, which will need to be completed prior to commencement of
feasibility study mine planning work.
26.2 Waste Rock Facility
Additional geotechnical exploration and laboratory testing are required as part of
the feasibility study to further evaluate the following:
The foundation above Beaver Creek to confirm stability of the proposed waste
dump plan or possible alternative layouts;
The foundation and abutment areas of the sediment control structures (stability,
outlet works, spillway alignment and borrow material);
Diversion alignment to confirm constructability with respect to the bedrock
topography, channel seepage, peak flow erosion potential and outward fill slope
stability;
Waste rock toe area stability in the event temporary inundation of the waste rock
toe is required to achieve adequate storage capacity for the design storm event
and maintain facility footprints within Section 16;
Confirm the estimated density of the in-place waste rock. A higher density will
allow reduction in height and/or footprint of the WRF.
Confirm estimated waste rock strength parameters for use in the WRF feasibility
study stability analysis.
Confirm the pit expansion schedule and groundwater conditions to confirm that
the final location and capacity of the pit dewatering pond (currently located
between the pit and PUG Plant) is acceptable.
Confirm whether Beaver Creek will be diverted or avoided in the WRF footprint.
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