16
production is expected to be complete within one year. The updated December 2013 NI 43-101
compliant resource estimate of total M&I rare earth elements is expected to extend the life of the
mine to 43 years.
4.5.4 Mine Facilities
4.5.4.1 Mineable Pit
It is anticipated that the Mineable Pit will be developed as shown on Map 4.2-2 with a
disturbance footprint of approximately 232 acres. The updated NI 43-101 compliant resource
estimate includes 1,043 million pounds of M&I rare earth oxides within the greater Bull Hill and
Whitetail resource areas (RER, 2013). The M&I resource estimate supports the mine plan to
process 500 tons per day of higher grade ore for a period of up to 9 years followed by the
mining and processing of low and mid-grade ore for up to an additional 34 years at a production
rate of up to 1,000 tons per day.
The Bull Hill Mine will utilize conventional truck and excavator open pit mining methods. Topsoil
and overburden will first be removed to expose the mineable ore and then direct hauled to the
Waste Rock Facility or to topsoil stockpiles.
The mine will yield several types of ore, all of which will be hauled by truck from the Mineable Pit
to separate ore stockpiles located at or near the PUG Plant. The cutoff grade for the mine is 1.5
percent TREO. The ore types include: Bull Hill Oxide High Grade and OxCa and Whitetail Oxide
and OxCa. Direct mined waste rock, including overburden material from the mine will be hauled
and placed in the Waste Rock Facility. The Waste Rock Facility will be cleared and grubbed to
prepare the surface for deposition of the waste rock. It is anticipated that both bottom and end
dump trucks will be utilized to transport and place waste rock and overburden from the pit to the
Waste Rock Facility. Map 4.2-2 identifies the haul route from the pit to the Waste Rock Facility.
Both the Bull Hill and Whitetail resource areas are included in the development of the Bear
Lodge Mine Hydrology and Hydraulics Plan (see Appendix D) and in the calculation of the
reclamation bond (Golder Associates, Inc. - Golder, 2012).
4.5.4.2 Waste Rock Facility
Over the life of the mine, waste rock will be generated while extracting the ore. A Waste Rock
Facility (located in Section 16 on private lands) and just east of the Mineable Pit will
accommodate waste rock from the Mineable Pit and coarse reject material from the PUG Plant.
In addition, a Low Grade Ore Stockpile will be located in the southwest corner of Section 16
within the Waste Rock Facility. The low grade material may eventually be processed. The
combined footprint of the Waste Rock Facility and the Low Grade Ore Stockpile is
approximately 426 acres (see Table 4.5-1).
The overall design components of the Waste Rock Facility and Low Grade Ore Stockpile
include foundation preparation, an underdrain collection system, and water management
structures. Foundation preparation involves cutting and removing trees and underbrush,
removing and stockpiling topsoil for reclamation, and removal of any unsuitable material from
selected zones for slope stability purposes. The underdrain collection system will be installed
within the footprint of these facilities to intercept water from naturally occurring seeps and
springs and seepage from the Waste Rock Facility. Approximately 4,000 feet of Beaver Creek
diversion will be constructed to maintain drainage and water quality along the south side of the
facilities. The design specifications for storm water control are provided in Section 4.5.4.4 and
Appendix D.
RER has conducted and is continuing geochemical characterization of the waste rock to support
engineering design and permitting. The primary purpose of the waste rock characterization work
