Preliminary Public Dose Evaluation in Support of the Development of the
November 2012
Rare Element Resources Bear Lodge Project
12
2.3.1
Tailings Storage Facility
Tailings will be stored in an engineered, lined facility west of the plant. The TSF is designed to
meet applicable regulatory requirements of the Wyoming Department of Environmental Quality.
Details of the TSF preliminary design are presented in
Technical Report on the Mineral Reserves
and Development of the Bull Hill Mine
(RER, 2012).
The tailings are designed to be 5 percent solids slurry. The solids will be comprised of sulfate
sludge (72 percent), iron hydroxide ([FeOH] 7 percent), and compounds not leached by the
Hydromet process (RER, 2012). The tailings flow rate is estimated at 116 gallons per minute.
Currently, the TSF has a designed footprint of 314 acres with a storage capacity of
approximately 1 x 10
7
t. Its construction is expected to be staged holding approximately 1
million tons of tailings.
2.4
Radionuclide Content of Ore and Concentrates
Three general types of material will be produced by the BLP: 1) ore mined from the BHM, 2) a
pre-concentrate generated from the PUG, and 3) a carbonate concentrate product from the
Hydromet.
2.4.1
Bull Hill Ore
Ore from the BHM can be grouped into the following four general types:
•
Oxide high grade ore containing a mass percentage of Total Rare Earth Oxide (TREO)
greater than 1.5 percent
•
Oxide-carbonate ore containing a mass percent of TREO greater than 1.5.
•
Oxide stockwork containing a mass percent of TREO greater than 1.
•
Oxide low grade ore containing a mass percent of TREO greater than 0.5.
Table 2.1 summarizes the natural thorium and uranium content of these materials. These data
demonstrate that thorium is much more abundant than uranium in the BHM ores.
