Rare Earth Elements: A Review of Production, Processing ...

Rare Earth Elements Review Section 3 – Life-Cycle Stages of Rare Earth Elements Mines
Drilling will also displace ground water entering the borehole to the ground surface, along with the
drilling fluids. These formation fluids can be highly mineralized, and the cuttings and drilling muds can
entrain toxic levels of metals and other chemicals. Drill cuttings and drilling fluids are typically collected
once the borehole is completed and abandoned; however, regulations in some states allow return of
cuttings to the borehole. Excess materials may be stored in drums, contained in mud pits, or managed and
disposed of as a waste.
Locations in the United States with Recent Exploration Activity and a Summary of Potential REE
Resource Areas
Potential sites of REE resources have been under evaluation in recent years to prove the reserves and
determine the mining potential at these locations. Sites receiving current or recent attention are located in
Utah, Colorado, Wyoming, Alaska, California, Nevada, and Nebraska.
� During 2008, the Great Western Minerals Group, Ltd. completed an extensive drilling and
sampling program at the Deep Sands deposit located in the Snake Valley and adjacent to the Deep
Creek Mountains of west-central Utah. After a feasibility study to consider the low-grade
monazite mineral ore containing rare earth concentrations, the company announced that it did not
currently plan to undertake additional exploration at the site (Great Western Minerals Group,
2011).
� A recently formed company, Colorado Rare Earths Incorporated (CREI), announced in March of
2011 that it was soliciting funding to begin exploration near the Powderhorn mine site in
Colorado (Colorado Rare Earths, Inc, 2011). CREI also has acquired properties at Iron Hill and
Wet Mountains Colorado, where potential REE resources have been identified. CREI is currently
organized as a mineral claims acquisition company, but plans to expand to an exploration and
development company in the future.
� In Alaska, exploration is underway at the Bokan Mountain site that is located at the southernmost
end of the Alaskan panhandle on Prince of Wales Island. This is a site that was mined in the
past for uranium ore, but also has known HREE and LREE resources.
� Molycorp Minerals, as described earlier, is a past producer of REEs and is currently preparing to
re-open its mine at Mountain Pass, California.
� In Nevada, about 16 miles east of the Mountain Pass mine, Elissa Resources is exploring multiple
locations called the Thor REE Project Area, where HREEs and LREEs have been discovered; at
least one of these locations is geologically similar to the Mountain Pass deposit (Elissa
Resources, 2011). To date, Elissa Resources’ exploration activities have included surface
mapping, a district-scale detailed high-resolution airborne magnetic geophysical survey,
extensive ground radiometric surveys, satellite imagery studies, petrographic studies, and
sampling programs, including channel sampling and the sampling of historical surface workings
that are remnants of a 1950s uranium-thorium prospecting rush.
� Quantum Rare Earth Developments Corporation recently has begun exploratory drilling at the Elk
Creek Project in southeastern Nebraska. The focus of these drilling efforts is to perform a
resource assessment of niobium and associated REEs contained in a carbonatite deposit. These
efforts are in the early stages, and no final determination about the resource has been made at this
time (Quantum Rare Earth Developments Corporation, 2010).
� Bear Lodge Rare-Earth Project is located approximately 6 miles north of Sundance, Wyoming,
and is comprised of 90 unpatented federal lode claims and one state lease, for a total of about
2400 acres. It is owned by Rare Element Resources through its Wyoming-incorporated Paso Rico
(USA) Company, Inc. Twenty-three of the mining claims were obtained from Phelps Dodge
Corporation and are subject to 2-percent net smelter return production royalty. The site has been
prospected at various times since 1949. Several areas of mineralization have been identified,
including high-grade copper, molybdenum, gold, and REMs within an altered carbonatite-
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