NI43-101Pre-Feasibility Study Report - page 46

Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
th
, 2014
10135-200-46 – Rev. 0
1-4
shipment to the Hydromet plant. The Bull Hill deposit contains varying proportions of
weathered high-grade oxide and oxide-carbonate ores, along with variable grades of
stockwork mineralization adjacent to the higher-grade ores. Each of these ore types
will have a different mass reduction and upgrade percentage in the PUG circuit. The
mineral pre-concentrate produced at the PUG will be transported by covered truck to
the Hydromet plant in Upton.
The Hydromet plant is designed to process the pre-concentrate through acid leaching
followed by the Company’s proprietary recovery technology. This process uses a
chloride solution to extract the rare earth elements (REE) into a liquid, and then uses
oxalate reagents to facilitate the selective precipitation of the REE. The benefits of
this process are that it achieves a high-purity, nearly thorium-free, bulk TREO
concentrate, and has the ability to regenerate and recycle a majority of the reagents
used in the process, including acid and water.
In the PFS, the rare earth recovery rate is expected to be approximately 88.3% in the
Hydromet process over the LOM. The average annual LOM nominal TREO
production rate is anticipated to be approximately 7,510 tons (6,813 tonnes). The
tailings produced from the processing will be neutralized, dewatered, and stored in an
engineered, lined tailings storage facility (TSF) located on private land adjacent to the
Hydromet plant.
The Project is sized to balance initial capital requirements and still be a meaningful
supplier for current market demand, while minimizing the Project’s environmental
footprint. The plant is designed to have sufficient flexibility to produce higher
tonnages of rare earth concentrates when market conditions warrant, with only minor
modifications and optimization of operating parameters.
1.1 Mineral Reserves and Resources
The Company previously announced a Measured and Indicated (M&I) mineral
resource of 17.3 million tons (15.7 million tonnes) averaging 3.11% TREO, and an
Inferred resource of 29.3 million tons (26.6 million tonnes) averaging 2.58% TREO
(see the Company’s news release dated March 17, 2014). The additional work done
to prepare the PFS resulted in an increase in the M&I resource tons by approximately
4% and a slight reduction of the average grade, from 3.11% to the current 3.05%
(using a 1.5% cutoff grade). The current mineral resource is shown in Table 1.2:
1...,36,37,38,39,40,41,42,43,44,45 47,48,49,50,51,52,53,54,55,56,...587
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