DRC-2020-015241 - 0901a06880d249ad

Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, CO, US, 80228
303 974 2140
www.encrgyfuels.carn ENERGY FUELS
September 9, 2020
SENT VIA E-MAIL AND EXPEDITED DELIVERY
Mr. Ty L. Howard
Director
Division of Waste Management and Radiation Control
Utah Department of Environmental Quality
195 North 1950 West
Salt Lake City, UT 84116
Div of Waste Management
and Radiation Control
SEP - 9 2020
-P2C-Z020-0152+1
Re: Response to Utah Division of Waste Management and Radiation Control ("DWMRC")
Request for Additional Information (RAI) regarding the Energy Fuels Resources (USA) Inc.
("EFRI"), June 25,. 2020 Letter Regarding Receipt and Processing of Ores from Chemours at the
White Mesa Uranium Mill Utah (the "Mill"); Groundwater Discharge Permit No: UGW370004
("GWDP") and Utah Radioactive Materials License UT 1900479 ("License")
Dear Mr: Howard:
This letter responds to DWMRC's letter dated July 21, 2020 regarding the DWMRC Request
for Additional Information ("RAI") regarding EFRI's, June 25, 2020 letter regarding receipt and
processing of ores from Chemours at the Mill (the "Ore") for the recovery of uranium and a rare
earth element ("REE") concentrate ("REE Concentrate").
As will be discussed in detail below in response to DWMRC' s questions, the Ore is a natural
uranium ore that is similar in radionuclide and chemical content to other ores and alternate feed
materials that are processed on a routine basis at the Mill. The Ore can be processed at the Mill
for the recovery of uranium and an REE Concentrate under existing processes and standard
operating procedures with m.inor routine modifications and adjustments typical of the types of
modifications and adjustments made by the Mill in its normal processing activities associated with
the various ores and feeds it processes on a regular basis.
Because all the constituents in the Ore have either been reported to be, or can be assumed to be,
already present in the Mill's Tailings Management System ("TMS") or were reported in other
conventional ores or licensed alternate feed materials* or in reagents already in use at the Mill, at
levels generally comparable to or higher than those reported in the Ore, the resulting tailings will
not be significantly different from existing tailings at the facility, and the impacts will not be
significantly different from the Ore than from other conventional ores and previously licensed
alternate feed materials. Consequently, there will be no incremental public health, safety or
environmental impacts over and above existing licensed activities.
Letter to Ty L. Howard
September 9, 2020
Page 2 of 41
As a result, although not expressly evaluated in previous analyses, the process of extracting an
REE Concentrate has been environmentally evaluated for the Mill, through the evaluation of
similar activities.
Althongh this letter responds to DWMRC' s questions relating to the Ore, the analysis below
demonstrates that natural monazite sand ores having similar characteristics as the Ore can be
handled easily and safely at the Mill in much larger volumes than the volumes associated with the
Ore as set out in our June 25, 2020 letter. Our June 25, 2020 letter contemplated receipt of
approximately 5,000 tons of Ore from Chemours' mines per year over a ten-year period. For
purposes of the analysis below, however, we have assumed annual receipts of 15,000 tons of Ore
or similar natural monazite sand ores per year from other sites on an ongoing basis, in order to
analyze any potential impacts if the Mill were to receive additional monazite sands with similar
characteristics from other sites in the future. As will be evident from the following analyses, the
receipt, processing and disposal of the tailings from 15,000 tons of natural monazite sands similar
to the Ore per year on an ongoing basis would fall well within the environmental envelop for the
Mill and would result in no incremental public health, safety or environmental impacts over and
above previously licensed activities. In fact, as demonstrated in this letter, even quantities of Ore
or similar natural monazite sand ores double that amount (i.e., 30,000 tons per year on an ongoing
basis) could be handled easily and safely at the Mill with no incremental public health, safety or
environmental impacts over and above previously licensed activities.
For ease of review, the DWMRC comment or request has been repeated in italics, below,
followed by El-RI' s response.
DWMRC COMMENT
RAI 1 — Additional information needed to support claims of 0.26% U308 in the Chemours
Monazite Mineral Sand meet the definition of uranium ore
EFRI states on page 4 of the letter that the Chemours material has a grade of 0.26% U308. The
EFRI letter includes an Attachment D Table which is referred to as "a summary of the mineral
composition of a typical ore produced in 2019" (Page 4). It is assumed that the EFR letter is
claiming that the Chemours monazite sand will contain a consistent percentage of recoverable
uranium, however, there is no source for the data provided in Attachrnent D and no way to confirm
that consistent percentages will be present for all material accepted at the Mill. Please provide
the data and sources used to claim the U308 concentrations of the Chemours Material as well as
justification that all material received from the Mission mine and the multiple future mines and
sources of mineral sand will contain a consistent percentage of recoverable uranium.
At a minimum, it needs to be documented with analytical data that the Chemours material will
always meet the definition of source material ore per the Utah Administrative Code R-313-12-3
(see also 10CFR40.4) contain by weight one-twentieth of one percent (0.05 percent) of uranium
for acceptance at the White Mesa Uranium Mill.
Letter to Ty L. Howard
September 9, 2020
Page 3 of 41
EFRI RESPONSE:
The data in Attachment D of the June 25, 2020 letter was provided by Chemours on December 25,
2019. In July 2020, Chemours provided additional mineral and uranium data for the Ore separated
at the Offerman site from a range of sand sources at the Mission Mine. The uranium data is
provided in Table 1, attached to this response letter. Table 1 includes the U308 and U-nat value
from EFRI' s June 25, 2020 letter to DWMRC, which was provided to EFRI by Chemours as what
Chemours believed would be representative of "typical Ore" to be sent to the Mill (referred to in
Table 1 as "Sample data from email"), as well as data from other samples collected by Chemours
during 2019-2020 (referred to in Table 1 as Rem(s) 1-6). The data show a range of 0.18% to
0.26% U308, with an average of 0.20% U308 (0.15% U-nat to 0.22% U-nat, with an average of
0.17% U-nat). All samples contained greater than 0.18% U308 (0.15% U-nat).
We have also provided in Table 1 the typical, minimum, and maximum uranium content data from
other separated monazite sands, produced in Africa, and identified at Queensland, Australia (WNA
2019). These are expected to be typical of other monazite sand ore sources that EFR1may evaluate
for processing in the future. All samples from every source (not just the average of samples)
contained 0.1% or higher U-nat grades.
Based on the above information, the Ore, and other typical natural monazite ores that may be
considered by EFRI in the future, are expected to meet the definition of source material ore.
Having said this, however, ores received at the Mill do not need to have a concentration of 0.05%
U-nat or higher.
When reviewing a prior U.S. Nuclear Regulatory Commission ("NRC") interpretation of the
Atomic Energy Act's ("AEA's") definition of byproduct material, the Court of Appeals for the
District of Columbia Circuit found that under the Uranium Mill Tailings Radiation Control Act
("UMTRCA") "low-grade feedstock ore containing less than the 0.05% uranium necessary to
constitute source material" could be treated as "ore" for the purpose of the definition of 1 le.(2)
byproduct material (which means that processing any such ore primarily for the recovery of
uranium would result in 1 le.(2) byproduct material, and would be acceptable). See Kerr-McGee
Chemical Corp. v. NRC, 903 F. 2d 1 (D.C. Cir. 1990).
In that case, the Court stated:
Throughout the AEA, different classes of materials are dealt with in accordance
with their physical properties and place within the nuclear fuel cycle. The
UMTRCA is no different. In section 11(e) (2), as originally presented in the
UMTRCA, byproduct material was defined as "the tailings or wastes produced by
the extraction or concentration of uranium or thorium from source material." H.R.
13382, 95th Cong., 2d Sess. Sec. 1 (1978) (emphasis added). Because of his
concern that tailings resulting from the processing of low-grade feedstock ore
containing less than the 0.05% uranium necessary to constitute source material
Letter to Ty L. Howard
September 9, 2020
Page 4 of 41
under NRC rules wonld escape regulation under the proposed definition, then-NRC
Chairman Dr, Hendrie suggested that the definition of byproduct materials
proposed in section 11(e) (2) be revised to substitute 'any ore processed primarily
for its source material content" (the language now appearing in the section) for the
words "source material." Hearings at 343. When questioned as to the significance
of the phrase "processed primarily for its source rnaterial content," Dr. Hendrie
explained that the language was intended to avoid bringing within NRC jurisdiction
radioactive wastes resulting from activities not connected with the nuclear fuel
cycle, which would be left to EPA regulation. The following exchange between
Dr. Hendrie and Subcorntnittee Chairman Dingell is instructive:
MR. HENDR1E. Mr. Chairman, the intent of the language is to keep NRC's
regulatory authority prirnarily in the field of the nuclear fuel cycle. Not to extend
this out into such things as phosphate mining and perhaps, even limestone mining
which are operations that do disturb the radium-bearing crust of the Earth and
produce some exposures but those other activities are not connected with the
nuclear fuel cycle, EPA is looking at those and those appear to me to be things that
ought to be left to EPA regulation under the Resource Conservation Recovery Act
and general authorities.
MR. DINGELL. Your thesis is that we ought not however set up a set ot'
circumstances where we would leave some of these to fall between the cracks and
wind up being unregulated.
MR. HENDRIE. I agree fully. Mr. Chairman, and I believe the way the language
would cut here, as we recommended, would not leave any crevasse between the
two authorities.
Id. at 344. It is clear from this exchange that the definition of "byproduct material"
proposed by Dr. Hendrie and adopted by Congress was designed to extend the
NRC's regulatory authority over all wastes resulting from the extraction or
concentration of source materials in the course of the nuclear fuel cycle.
The Court further stated:
A construction of section 11(e) (2) is not acceptable if it will orphan mill tailings
having a source material content of less than the 0.05% threshold, as is usually the
case.
In fact, the Sweetwater uranium mill in Wyoming (which is currently scheduled for reclamation)
was licensed and constructed to mill an ore body that had less than 0.05% U3OK (less than 0.0424%
U) and in fact throttghout its operating life processed uranium ore averaging less than 0.03% U308.
The Sherwood uranium mill in Washington State (now reclaimed) was designed to process ores
averaging less than 0.10% U308, and the average ore grade actually processed during its
Letter to Ty L. Howard
September 9, 2020
Page 5 of 41
operational life was likely less than 0.08% U308 (0.0678% U), with some of the ore being
processed likely having a grade of less than 0,05% U3OR .(0.0424% U).
As a result, even though the Ore and other monazite sand ores that may be available for processing
at the Mill are expected to contain greater than 0.05% U-nat, they do not need to contain that level
of U-nat, so long as they are being processed for the recovery of uranium at a licensed uranium
mill and it is reasonable to expect that uranium will be recovered, as is the case with the Ore,
lt should also be noted that the Ore is natural ore. The steps at Chemours' mines and separation
plant do not alter the oxidation state of the natural uranium or other minerals in the excavated
sands. The excavated sand grains are typically coated with a film of microbial or other formerly
living material settled from the channel or water body where the materials were originally
deposited. As disussed in EFRI.'s letter of June 25, 2020, the• mild alkaline/caustic rinse used at
the mine simply enables the wash water to better remove the natural biological/organic film from
the sand grains. The washing is not conducted at the elevated temperatures, high strength of
digestive reagent, or extended contact time necessary to convert the contained minerals within the
sand grains. The alkaline wash is incapable of chernically reacting with or changing the oxidation
state of uranium or any of the other minerals, nor is that its purpose.
Further, Chemours' separation sequence is not ablation. Ablation uses energy of impact and
compression/decompression to spall off or remove the attached mineral coating from the outšide
of each grain of a mineralized sand. Chernours' sequence does not compress/decornpress or
remove the minerals from the sand in which, and on which, they are bound. Chemours' sequence
only separates sands with different mineral coatings, but each of the separated products is still
mineralized sand with the mineral coating attached, as indicated in the flow schematic in
Attachment C of EFRI' s June 25, 2020 letter (staurolite sand, ilmenite sand, leucoxine sand, rutile
sand, monazite sand, among others).
References
WNA, 2019 Uranium frotn Rare Earth Deposits World Nuclear Association September 2019
accessed at https://www.world-nuclear.org/inforrnation-library/nuclear-ftieheyele/uraniuill-
resources/uranium-from-rare-earths-deposits.aspx
Kerr-McQee Chemical Corp. v. NRC, 903 F. 2d 1 (D.C. Cir. 1990).
DWMRC COMMENT
RAI 2 — Additional information needed to evaluate potential changes to Mill Tailings
Constituent Inventory and concentrations for evaluation of Groundwater Permit Monitoring
Requirements
The EFRI letter .does not inctude specific evaluation of the impacts to the rnill tailings due to. the
processing and disposal of the Chemours material tailings. Page 4 of the EMI letter generally
discusses that the. Chemours material should not require any additional mill processes; however,
Letter to Ty L. Howard
September 9, 2020
Page 6 of 41
DWMRC notes that monazite sand is not chemically consistent with uranium/vanadium ores from
the Colorado Plateau and Arizona Strip which were evaluated when determining compliance
monitoring requirements of the Mill in the Groundwater Permit Statement of Basis, Please submit
a more detailed EFRI evaluation of the uranium/rare earth mineral ore which will be processed
and disposed of in the tailings cells using the anticipated Mill processes (existing or new),
including an evaluation of expected changes in constituent concentrations in the tailings
management systern and potential new constituents which may need to be included in the
Groundwater Permit as a result of processing a uranium ore with rare earth minerals,
EFRI RESPONSE:
The 17 REEs are: cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd),
holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr), promethium
(Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium (Tm), ytterbium (Yb) and yttrium
REEs are all metals. The REEs are collectively referred to as "rare earth metals." The long-term
use of REEs as catalysts, and the ever-increasing demand for REEs in magnets, cell phones,
batteries, microprocessors, wind turbines, and GPS equipment, among others, are all based on their
metal properties, (King, 2018). Historically, they have been referred to as rare earth metals or
REMs. Because these elements are frequently used in their oxide form, or in the form of oxide
complexes, they are also sometimes referred to as rare earth oxides. For simplicity, for the
remainder of this evaluation they will be discussed as metals, and referred to as REEs.
As mentioned in the response to RAI 1 above, Chemours provided uranium and mineral data from
seven sarnples collected during 2019 and 2020, each sample weighting 15 pounds or more. The
data, provided in the Attached Table 2, was produced by XRF analysis in Chemours' on-site
assay/quality control lab.
As indicated in Table 2, all of the 17 REEs, with the exception of lutetium (Lu) and promethium
(Pm), were present in one or more of the samples from the Ore.
Evaluation of the Ore and any Expected Significant Changes in Constituent Concentrations in
the TMS
Presence of REEs in Other Uranium Ores. The processing of conventional uranium ores has been
adding REEs to the Mill's TMS since the startup of the Mill. Although historically REEs were
generally not quantified in uranium resource assessments, REEs are commonly present in uranium
ores, including ores from the southwestern United States such as the ores from the Four Corners
area and Arizona Strip previously and currently processed at the Mill.
Table 3, Column A, summarizes the ranges of REEs identified in Arizona Strip and Four Corners
area (Grants Mineral Belt) ("AZ/CO") uranium ores. At least one additional REE not identified
in the Ore, lutetium (Lu), is also present at measurable levels in AZ/CO ores. Promethium has not
been identified in measurable amounts in the earth's crust, and it has not been identified in the Ore.
Letter to Ty L. Howard
September 9, 2020
Page 7 of 41
It is known to be present only in trace quantities in some uranium ores as a decay product of
uranium. Therefore, although the level cannot be quantified and it does not show up on Table 3,
it can be assumed that some trace level of promethium is likely present in ores previously processed
at the Mill and in the TMS.
Other natural uranium deposits have been documented as containing REEs. For example, the
Molycorp Mountain Pass deposit, which is currently the largest rare earth hard rock deposit in the
U.S., was first explored as a uranium ore source (Green 2019). This uranium deposit contained
areas of 10 to 30% bastnasite (containing the REEs lanthanum, cerium and yttrium) and up to 20%
other rare earth minerals in the natural ore prior to processing for concentrations of any mineral.
Uranium content ranged from 0.004 to 0.55% uranium. Due to the high REE content and low
uranium market price at the time of discovery, it was developed as an REE resource (Olson et. al.
1954). The Bear Lodge deposit in Wyoming is another example of a natural uranium deposit in
the American west that has been documented as containing REEs (USGS 2017).
Other examples of REEs being common in conventional uranium ores are: (A) the Stepnogorsk
northern Kazakhstan plant, which is under construction to extract the REE dysprosium from
conventional uranium tailings (USGS 2017); and (B) in North America in the 1970's and 1980's,
Denison Mines, Inc. (a predecessor of Denison Mines Corp., the previous owner of the Mill)
recovered the REE yttrium frorn conventional uranium ore tailings solutions at the Elliot Lake,
Canada mill (IAEA 2018). Additionally, in recognition of the fact that REEs are frequently
identified in uranium ores, one way of assessing the geologic history of a uranium ore deposit is
to track the relative abundances of REEs (Mercadier, et. al. 2011).
Finally, the National Academy of Sciences and USEPA have assumed that highly elevated levels
of barium and a range of REEs are normally present in uranium Mill tailings, as a result of their
presence in uranium ores (NAS 1986, USEPA 1982).
As a result, Arizona Strip uranium ores processed at the Mill are expected to contain REEs within
the ranges indicated in Table 3, and, although not quantified, other uranium ores processed at the
Mill from the Colorado Plateau area are also expected to contain REEs generally within the ranges
indicated in Table 3.
Assumptions Used to Quantify REEs in Mill Tailinas. In the case of other natural uranium ores,
EFRI processes the ores for the recovery of uranium, and in some cases vanadium, values. In the
case of the Ore, EFRI intends to process the Ore for the recovery of both uranium and an REE
Concentrate. Just as is the case in other uranium ore processing, after the econoinically valuable
minerals are recovered (in this case both uranium and REE Concentrate), only the residual solids
and solutions will be discharged to the TMS. Therefore, under normal conditions, only a small
fraction of the REEs contained in the Ore, expected to be approximately 5%, will be discharged to
the TMS from Ore processing. That small fraction of REEs will behave chemically like other
metals and mineral components in the TMS.
Although EFRI's June 25, 2020 letter contemplated receipt of approximately 5,000 tons of Ore
from Chemours' mines per year over a ten-year period, for purposes of the analysis below, we
Letter to Ty L. Howard
September 9, 2020
Page 8 of 41
have assumed annual receipts of 15,000 tons of Ore or similar natural monazite sand ores per
year from other sites on an ongoing basis, in order to analyze any potential impacts if the Mill
were to receive additional natural monazite sand ores with similar characteristics from other sites
in the future. As will be evident from the following analyses, the receipt, processing and disposal
of the tailings from 15,000 tons of natural monazite sand ores similar to the Ore per year on an
ongoing basis would fall well within the environmental envelop for the Mill and would result in
no incremental public health, safety or environmental impacts over and above previously
licensed activities. In fact, as demonstrated in this letter, even quantities of Ore or similar natural
monazite sand ores double that amount (i.e., 30,000 tons per year on an ongoing basis) could be
handled easily and safely at the Mill with no incremental public health, safety or environmental
impacts over and above previously licensed activities.
In order to quantify and evaluate the REEs expected to be introduced into the TMS from Ore and
similar natural monazite sand ore processing, EFRI has performed the following evaluation
assuming all of the conventional ores processed at the Mill to date contained the average REE
concentrations listed in Column B of Table 3, and assuming the Mill:
• receives 15,000 tons of Ore or similar natural monazite sand ores per year on an ongoing
basis;
• processes 15,000 tons of Ore or similar natural monazite sand ores per year for nine years
out of every ten years recovering REE Concentrate and uranium;
• achieves 95% recovery of REEs and discharges 5% of REEs to the TMS for nine years out
of each ten-year period;
• to conservatively analyze for any impacts from REEs on the TMS, we have assumed the
Mill accumulates but does not process one year of receipts in each ten-year period, i.e.
15,000 tons of Ore or similar natural monazite sand ores are discharged to the TMS
unprocessed one year out of each ten years (for example if there were a process upset or if
the Mill were to go into reclamation prior to processing the Ore or similar natural monazite
sand ore receipts for that year);
• discharges to the TMS 100% of any constituent in the Ore or similar natural monazite sand
ore which is not an REE or uranium, assuming the average non-REE constituent
concentrations for the Ore or other monazite sand are as set out on Table 2.
• the tailings frorn processing the Ore and similar natural monazite sand ores are initially
deposited in Cell 4A, which is assumed to be filled to capacity with such tailings and other
Mill tailings from processing other uranium and uranium/vanadium ores and alternate feed
materials over the next ten years (i.e., tailings from processing Ores or other similar natural
monazite sand ores totaling 150,000 tons over the next ten years would be deposited in Cell
4A along with tailings from other uranium processing at the Mill, at which time Cell 4A
would be completely filled up);
• after Cell 4A is filled up, the tailings from processing Ore and similar natural monazite
sand ores are deposited in subsequent tailings cells, each of which is assumed to be filled
to capacity with such tailings and other Mill tailings from processing other uranium and
uranium/vanadium ores in a ten-year period (i.e., tailings from processing Ores or other
similar natural monazite sand ores totaling 150,000 tons over the ten-year period would be
deposited in each cell by the time it is completely filled up); and
Letter to Ty L. Howard
September 9, 2020
Page 9 of 41.
• under these assutnptions, the Mill would receiVe 15,000 tons of Ore or similar natural
monazite sand ore each year over the Mill's life, the tailings froth which would be placed
into successive tailings cells, with each tailings cell assumed to receive a total of 150,000
tons of such Ore and similar natural monazite sand ores at the time the Cell is filled up and
taken out of operation. As a result, the analysis performed for Cell 4A is considered to be
representative of the impacts to each successive tailings cell.
As will be evident from the discussion below, the introduction of constituents into the TMS from
processing Ore and similar monazite sand ores will not have any impacts on the TMS and is
therefore not a concern. Nor would there be a concern if the concentrations of those constituents
were higher or the quantity of the Ore or similar monazite sands were higher than •the amount
assumed for this analysis.
Evaluation of any Expected Significant Changes in Constituent Concentrations in the TMS. The
evaluation below addresses the expected composition of tailings and the chemical and
environmental behavior of the tailings from the introduction of Ore or siniilar natural monazite
sand ores into the TMS.
Table 4 summarizes the anticipated composition of the tailings solution after processing Ore and
similar natural monazite sand ores. The calculations assume that all of the REE content of the Ore
or other monazite sand for one year, and 5% of the REE content for nine yeam, will be discharged
to Cell 4A over the remaining ten-year operational phase of Cell 4A, as described above. Cell 4A
was used as representative of the receiving tailings cell. Table 4 assumes that the tailings from a
total of 150,000 tons of Ore or similar natural monazite sand ores are deposited in Cell 4A and that
the remainder of Cell 4A is filled up with other Mill tailings.
The most appreciable change in concentration from processing the Ore or similar natural monazite
sand ores will result from barium and zirconium. Although to a much lesser degree, noticeable
changes in lead, gallium, hafnium, natural thorium (sometimes referred to in this letter as "Th.-
mit") and certain REEs are also expected. Each of these constituents is not a concern, as detailed
below.
(a) Barium (Ba).
Although there should be little barium in the tailings solutions from processing Ore, because
it will precipitate with sulfate, for purposes of this analysis, we have assumed all the barium
will report to the tailings solutions. Barium has been addressed at length in EFRI's amendment
request for Dawn Mining alternate feed material. In addition to the introduction of barium into
the TMS with. the Dawn Mining material, barium has previously been introduced into the Mill
and TMS with the Molytorp alternate feed material, at greater concentrations than are present
in the Ore, with no harmful effects to the Mill or TMS. Further, barium chloride is a typical
:additive to uranium mine water treatment facilities to precipitate radium from the water prior
to discharge. Some of those facilities have impoundments which are lined with the same PVC
or HDPE liner materials used for the Mill's TMS. High concentrations of barium chloride in
those facilities are not considered to result in any degradation to the liners in those systems.
Letter to Ty L. Howard
Septernber 9, 2020
Page 10 of 41 •
Polymeric materials such as' PVC and HDPE are selected for geomerribrane liners specifically
because they are resistant to solutions of metals and metal salts, like barium, in all proportions
(USEPA 1988). As a result, the introduction of barium into the TMS from processing Ore or
in any quantity or proportion is not a concern.
(b) Zirconium (Zr).
Zirconium has been present in the TMS and will behave as all other metals in the tailings
solutions. Zirconium has been received and processed in other ores and alternate feed
materials, such as the FMRI Metal Resources Inc. ("FMRI") material, as indicated in Table 6,
and in the Cabot alternate feed material, with no harmful effects to the Mill or TMS. Elevated
concentrations of zirconium are not expected to result in degradation to the TMS cell liners.
Polymeric materials such as PVC and HDPE are selected for geomembrane liners specifically
because they are resistant to solutions of metals and metal salts, like zirconium, in all
proportions (USEPA 1988). As a result, the introduction of zirconium into the TMS from
processing Ore or in any quantity or proportion is not a concern.
(c) Lead (Pb).
The Mill has previously processed other feeds with significantly higher concentrations of lead
than the Ore with no deleterious effects to the Mill or the TMS. For example, Molycorp
alternate feed material contained lead up to 262,400 mg/kg, or more than a 240 times greater
lead concentration than the Ore. The license amendment request for the Molycorp alternate
feed materials, which was approved by the NRC in 2001, was for 17,750 tons of material. The
mass of lead expected to be contributed to the TMS (in Cell 3) from the Molycorp material
was therefore up to 4,658 tons of lead compared to the 163.8 tons of lead from 150,000 tons
of Ore or similar natural monazite sand ore. Because the majority of tailings from alternate
feed materials processed to date have been disposed of in Cell 3, the contribution of lead to
tailings from processing Molycorp and other alternate feed materials with elevated lead are not
reflected in the quantitative estimate in Table 4. As a result, the 537.2% increase in Mill
tailings concentration after Ore processing grossly overstates the impact on the TMS from the
addition of lead from the Ore, compared to other ores and alternate feed materials. Were the
tailings from the Ore or similar nAtural monazite sand ore to be placed in Cell 3, the additional
contribution to lead in Cell 3 would be insignificant.
Nevertheless, elevated concentrations of lead are not expected to result in degradation to the
TMS cell liners. Polymeric materials such as PVC and HDPE are selected for geomembrane
liners specifically because they are resistant to solutions of metals and metal salts, including
lead, in all proportions (USEPA 1988). Additionally, the TMS was designed for long-term
management of the decay products of the radionuclides disposed of in the Mill tailings. Per
the 1997 EA for the Mill, the majority of radionuclides in the TMS will decay to lead, and the
TMS is appropriate for long-term management of lead. As a result, the introduction of lead
into the TMS from processing Ore or in any quantity or proportion is not a concern.
Letter to Ty L. Howard
September 9, 2020
Page 11 of 41
(d) Gallium (Ga).
Gallium is likely present in the TMS as a result of processing alternate feed materials (such as
bastnasite from Molycorp), but has not been analyzed to date. Elevated concentrations of
gallium are not expected to result in degradation to the TMS. Gallium will behave like other
metals with respect to the tailings cell liners. Polymeric materials such as PVC and HDPE are
selected for geomembrane liners specifically because they are resistant to solutions of metals
and metal salts, like gallium, in all proportions (USEPA 1988). As a result, the introduction
of gallium into the TMS from processing Ore or in any quantity or proportion is not a concern.
(e) Hafnium (Hf).
Hafnium is likely present in the TMS as a result of processing alternate feed materials, because
it is frequently co-present in minerals and mineral slags containing zirconium (such as alternate
feed materials from FMRI and Cabot which were known to contain zirconium minerals), but
has not been analyzed to date. Elevated concentrations of hafnium are not expected to result
in degradation to the TMS. Hafnium will behave like other metals with respect to the tailings
cell liners. Polymeric materials such as PVC and HDPE are selected for geomembrane liners
specifically because they are resistant to solutions of metals and metal salts, like hafnium, in
all proportions (USEPA 1988). As a result, the introduction of hafnium into the TMS from
processing Ore or in any quantity or proportion is not a concern.
(f) Thorium (Th).
Natural thorium is found in low concentrations in uranium ores. Typical sandstone-hosted
uranium ores (e.g., Colorado Plateau ores), contain approximately 0.2 to 2.2 pCi/g Th-232
(0.0002 to 0.002% Th-nat). See: NRCP Report No. 118 (1988) and Cardarelli 1999. Other
uranium mines in the world have higher natural thorium concentrations. For example, natural
thorium concentrations in several uranium mines in Canada have ranged from 0.05% to
0.225%. See CanMet 1977.
The Mill has processed a number of alternate feed materials, including those from Sequoyah
Fuels and Heritage Minerals, with elevated levels of thorium. For example, the alternate feed
materials from Sequoyah Fuels had a Th-232 range of 1,060-4,990 pCi/g Th-232, with a
weighted average of 2,385 pCi/g Th-232, which equates to 0.95% - 4.50% Th-riat, with a
weighted average of 2.15% Th-nat. This is comparable to the Ore, which has a range of 2.26%
— 3.43% Th-nat, and an average of 3.18% Th-nat. As another comparison, the W.R. Grace
alternate feed material, which was approved for processing but was never processed at the Mill
for commercial reasons, had a Th-232 concentration ranging up to 31,500 pCi/g, with an
average of 8,000 pCi/g Th-232, which equates to a maximum of 28.4% Th-nat and an average
of 7.2% Th-nat. The natural thorium content of the Ore is therefore comparable to feed
materials processed at the Mill and well within the range of feed materials approved for
processing at the Mill.
Letter to Ty L. Howard
Septernber 9, 2020
Page 12 of 41
Historically, natural thorium was not measured on a mass concentration basis in tailings
solutions, and activity concentrations of three thorium isotopes, Th-228, Th-230 and Th-232,
have only been measured since 2015. Since natural thorium mass concentration was not
analyzed in tailings solutions, representative values for natural thorium in tailings were
estimated as follows. It was assumed that 7,520 tons of tailings from Sequoyah Fuels alternate
feed material, with their average natural thorium content of 2.15% Th-nat, were deposited in
Cell 4A. The natural thorium contribution for the remainder of the 2.15 million tons of total
tailings capacity in Cell 4A was estimated from the natural thorium value of 0.002% Th-nat
from NRCP Report No. 118 for conventional ores, assuming the remainder of the tailings in
Cell 4A are all from natural Colorado Plateau ores. Based on this analysis, the estimated total
natural thorium content in Cell 4A when full would be approximately 480.8 tons of Th-nat or
approximately 0.024% of the total Cell 4A tailings mass. This value is somewhat low because
it does not take into account tailings in Cell 4A from any other alternate feed materials with
elevated natural thorium levels. By comparison, 150,000 tons of Ore or similar natural
monazite sand ore would add approximately 4,762.5 tons of Th-nat to Cell 4A, or
approximately 0.24% of the total Cell 4A tailings volume when full.
Although the mass of natural thorium in Cell 4A would increase by 9.9 times, the percentages
are very small, and the concentration of Th-nat in the Ore is well within previously approved
concentrations and volumes. For example, the W.R Grace alternate feed material arnendment
application of April 12, 2000, approved by the NRC on December 20, 2000 for processing at
the Mill, was for up to 203,000 tons of material, with an average concentration of
approximately 7.27% Th-nat. The tailings from the W. R. Grace material were to be deposited
in Cell 3. Table 5 shows the impact on disposing of the W. R. Grace tailings in Cell 3, had
they been processed at the Mill, assuming Cell 3 was filled to capacity with other ores and
alternate feed materials in addition to the W.R. Grace tailings. As evident from Table 5, the
total mass of Th-nat contained in the W.R. Grace tailings was estimated to be 14,764 tons or a
concentration of approximately 0.54% of the mass of tailings in the cell, which is more than
two times the concentration in Cell 4A when full of 0.24% after receipt of tailings from 150,000
tons of Ore or similar natural monazite sand ores over the assumed ten-year operational life of
Cell 4A. What this means is that doubling the annual quantity of Ore and similar natural
monazite sand ores from 15,000 to 30,000 tons would still fall within the quantity and
concentration of Th-nat approved for the W. R. Grace alternate feed material for disposal in
Cell 3.
Thorium will behave chemically like other metals with respect to the tailings cell liners. As
discussed above, Polymeric materials such as PVC and HDPE are selected for geomembrane
liners specifically because they are resistant to solutions of metals and metal salts in all
proportions (USEPA 1988). As a result, the introduction of natural thorium into the TMS from
processing Ore or in any quantity or proportion is not a concern. Management of radiation
safety for elevated thorium in the Mill and tailings is addressed in the response to RAI 5, below.
As this analysis assumes that 150,000 tons of Ore or similar natural monazite sand ores are
added to each of Cell 4A, Cell 4B and proposed Cells 5A and 5B during their operational lives,
and the remainder of each cell is filled to capacity with other Mill tailings, and because each
Letter to Ty L. Howard
September 9, 2020
Page 13 of 41
of those cells is approximately the same size, the impact on Cells 4B and proposed Cells SA
and SE would ešsentially be the same as the impact analyzed above for Cell 4A: As a result,
the Mill could easily process 15,000 tons of Ore or similar natural rnonazite sand ores on a
yearly basis over the Mill's operational life, without any incremental impacts from Th-nat over
and above previously licensed activities. In fact, as demonstrated in this letter, even quantities
of Ore or similar natural monazite sand ores double that arnount (Le., 30,000 tons per year on
an ongoing basis) could be handled easily and safely at the Mill with, no incremental public
health, safety or environmental impacts .over and above previously licensed activities.
(g) REEs
As discussed above, although REEs are not monitored in the TMS, they are known to be
present in other ores which have been and will be processed at the Mill, and their content can
be estimated. During the period when Cell 3 was being filled with solids (to a capacity of
2320,000 dry tons), the approximate breakdown of ore tailings vs, alternate feed material
tailings, as wen as the REE content of ores, is known. If tailings from all the alternate feed
materials processed from the inception of the program in 1997, until the time Cell 4A was
available to receive tailings, were discharged to Cell 3, alternate feed materials provided only
17% of the tailings discharged to Cell 3. One or two previously-processed alternate feed
materials had measurably high contents of REEs, but their actual fraction of the 17% total can
only be estimated. Hence, the contribution of alternate feed materials to tailings and to the
REE content of Cell 3 was neglected for this calculation, and the REE content was based solely
on the ore contribution to tailings. The approximate concentrations of REEs developed for
Cell 3 were Used to represent the concentration of REEs in Cell 4A. It is assumed that tailings
from a comparable ratio of natural ores to alternate feed materials estimated for Cell 3 will be
discharged to Cell 4A over its operating life. The current approximate tailings mass and the
measured concentrations of other constituents in Cell 4A, as repotted in the Mill's annual
tailings solutions sampling report, were used to complete the calculations.
Additional information on the REE content of other feed,s which have been processed in the
Mill are provided in Column J of Table 4 and in Table 6. As mentioned above, since the exact
contribution of tailings mass from each alternate feed material can only be approximated, theSe
were not added to the concentration. That is, the concentration of REEs in tailings is likely
higher than the values indicated by the methods above.
REEs will behave chemically like other metals with respect to the tailings cell liners: As
discussed above, Polymeric materials such as PVC and HDPE are selected for geomembrane
liners specifically because they are resistant to solutions of metals and metal salts in all
proportions (USEPA 1988). As a result, the introduction of REEs into the TMS from
processihg Ore or in any quantity or proportion is not a concern.
Letter to Ty L. Howard
September 9, 2020
Page 14 of 41
Evaluation of any potential new constituents which may need to be included in the Groundwater
Permit as a result of processing a uranium ore with rare earth minerals
What follows is an evaluation of any potential new constituents which may need to be included in
the Mill's GWDP as a result of processing Ore at the Mill.
In the analysis above, we identified appreciable expected changes in concentrations in Cell 4A
tailings solutions from barium and zirconium, as a result of Ore or similar natural monazite sand
ore processing, with rnuch lesser but still noticeable changes in lead, gallium, hafniuin, natural
thoriuin and certain REEs.
As lead is already a constituent included in the GWDP, no further evaluations relating to lead are
required. We will therefore address each of the other of these constituents, barium, zirconium,
gallium, hafnium, natural thorium and REEs in turn, to determine whether or not they need to be
included as monitoring parameters in the GWDP,
Barium. Barium has been addressed at length in EFRI's amendment request for Dawn Mining
alternate feed material. As discussed therein, Barium is well-represented by the Mill's current
monitoring program. Barium will be chemically the same as magnesium, calcium, and other
alkaline earths already introduced into the Mill with other ores and with alternate feed materials.
These are currently present in large proportion in the Mill and TMS as discussed in Tables 4 and
6. The Mill currently analyzes tailings and groundwater for calcium and magnesium, which are
effective indicators for barium. As a result, there is no need to add barium as a _monitoring
constituent under the GWDP because of Ore or similar natural monazite sand ore processing.
Zirconium. Zirconium is a transition metal, and typically exhibits a +4 oxidation state. Based on
Sheppard et al (2011), the Kd value for zirconium in soils containing low amounts of clay and
organic matter (similar to the sandstones hosting perched groundwater at the Mill), is larger than
for uranium which is already monitored at the Mill. Uranium is therefore expected to be more
mobile than zirconium and would be detected sooner in any potential seepage from the TMS. As
a result, there is no need to add zirconium as a monitoring constituent under the GWDP because
of Ore or similar natural monazite sand ore processing.
Gallium. As with REEs, discussed below, Gallium exhibits the +3 oxidation state. As discussed
in Jensen (2017), gallium is strongly retained by the soil matrix with relatively large Kd values
ranging from 400 to 2000, Based on data provided in Sheppard et al, 2011, the Kd for gallium in
soils containing low amounts of clay and organic matter (similar to the sandstones hosting perched
groundwater at the Mill), is bracketed by the Kd for iron (Fe) and chromium (Cr) which are already
monitored at the Mill. In addition, uranium, which is already monitored at the Mill, is expected to
be much more mobile than gallium and would be detected sooner in any potential seepage from
the•TMS. As a result, there is no need to add gallinm as a monitoring constituent under the GWDP
because of Ore or similar natural monazite sand ore processing.
Letter to Ty L. Howard
September 9, 2020
Page 15 of 41
Hafnium. Like zirconium, hafnium is a transition metal, and typically exhibits a +4 oxidation
state. Based on Sheppard et al (2011), the Kd value for hafnium in soils containing low amounts
of clay and organic matter (similar to the sandstones hosting perched groundwater at the Mill), are
larger than for uranium which is already monitored at the Mill. Uranium is therefore expected to
be more mobile than hafnium and would be detected sooner in any potential seepage from the
TMS. As a result, there is no need to add hafnium as a monitoring constituent under the GWDP
because of Ore or similar natural monazite sand ore processing.
Natural Thorium. Natural thorium, like uranium, is an actinide, and typically exhibits a +4
oxidation state. Natural thorium and thorium 230, the daughter product from the uranium chain,
behave the same chemically. Natural thorium and thorium 230 have generally similar chemical
behavior as uranium. Based on Sheppard et al (2011), the Kd value for thorium in soils containing
low amounts of clay and organic matter (similar to the sandstones hosting perched groundwater at
the Mill), is larger than for uranium which is already monitored at the Mill. Uranium is therefore
expected to be more mobile than natural thorium and would be detected sooner in any potential
seepage from the TMS. Thorium 230, which behaves the same chemically as natural thorium, is
prevalent in the Mill's TMS and is not a monitored constituent under the GWDP for these reasons.
As a result, there is no need to add natural thorium as a monitoring constituent under the GWDP
because of Ore or similar natural monazite sand ore processing.
REEs. REEs include the lanthanides which consist of 15 elernents with atomic numbers 57-71
and the chemically similar elements scandium (Sc) and yttrium (Y). The REEs are commonly
segregated into light REE (LREE) and heavy REE (HREE) fractions for descriptive purposes, with
the separation occurring between europium (Eu) and gadolinium (Gd); Y is most similar to HREE,
and Sc is most similar to LREE in solution (Brookins, 1989). A middle REE (MREE) suite is also
commonly distinguished, although the specific elements are inconsistently defined between
studies.
Weathering of apatite is the most likely source of the general MREE-enrichment in groundwater
(Chevis et al, 2015); weathering of accessory minerals, such as apatite, and/or precipitation of
LREE-enriched secondary phosphate minerals controls general groundwater REE concentrations
and fractionation patterns (Chevis et al, 2015).
General groundwater samples studied in Chevis et al (2015) exhibited broadly similar middle REE
(MREE) enriched shale-normalized REE patterns, despite the wide variation in pH of these natural
waters (4.87 5 pH 5 8.13). The similarity of shale-normalized REE patterns across a pH range
4.87 5 pH 5 8.13 suggests that weathering of accessory minerals, such as apatite, and/or
precipitation of LREE enriched secondary phosphate minerals controls general groundwater REE
concentrations and fractionation patterns (Chevis et al, 2015).
The chemistry of the lanthanides is dominated by the +3 oxidation state. All lanthanide elements
form trivalent cations (3+); only Ce(IV) and Eu(II) are stable in oxidation states other than (3+) in
aqueous solution under environmentally relevant conditions. Oxidation of Ce(III) to Ce(IV)
results in cerium readily precipitating as CeO2(s); reduction of Eu(III) to Eu(II) results in lower
Letter to Ty L. Howard
September 9, 2020
Page 16 of 41
solubility and europium is preferentially incorporated into other minerals (similar to .Sr) (Brookins,
1989).
In natural groundwater-aquifer systems, the mobility and transport of REEs are mainly influenced
by the amoUnt and type of solution complexing ligands present and the groundwater pH (Noack et
al, 2014). Interactions with different mineral phases have been shown to alter REE patterns
predictably. For example, an MREE enrichment is observed for freshwater in contact with
phosphate-rich minerals (Hannigan and Sholkovitz, 2001; Chevis et al, 2015), while HREE
enrichment is found in carbonate-rich waters (Johannesson et al. 1996). Since the solubilities of
the REEs are typically low, both surface and solution complexation can be important in
fractionating REEs in aqueous solution and their relative importance varies as a function of the
overall solution composition (Johannesson and Xiaoping, 1997).
Groundwater pH generally exerts the greatest control over dissolved REE abundance (Noack et al,
2014), with more acidic waters generally containing the most REEs, either via acidification-
enhanced weathering or from an enrichment of REE in the acid source (Dia et al, 2000; Gosselin
et al, 1992; Gimeno Serrano et al, 2000; Goyne et al, 2010; Ayora et al, 2015; Olias et al, 2018;
Verplanck et al, 1999). Under more neutral and alkaline conditions REEs are effectively removed
from solution through sorption onto oxides and clays or coprecipitation with carbonates and
phosphates by replacing calcium, which has a comparable atomic radius (Bruque et al, 1980;
Maza-Rodriguez et al. 1992; Byrne and Kim, 1993; Johannesson et al, 1995; 1996; Coppin et al,
2002; Liu et al, 2017; 2019). Over the pH range 4-8, log dissolved REE abundance follows an
approximate —1 slope with increasing (Noack et al, 2014),
The REEs exhibit strong complexation with carbonate, particularly as a bicarbonato complex
[REE(CO3)21, and form progressively stronger carbonate and bicarbonato complexes with
increasing atomic number (Wood, 1990; Millero, 1992; Johannesson et al, 1995). This behavior
is similar to that displayed by uranium.
Inorganic speciation of the REEs in circumneutral pH (7 ~ pH ~ 9) groundwaters from the Great
Basin indicated REE-carbonate complexes [LnHC032+, LnCO3+ and Ln(CO3)2-1 dominate and
typically account for more than 99% of each REE in solution; the combined percentage of all REE-
phosphate complexes [LnH2P042+, LnHPO4*, Ln(HPO4)2- and LnP040] never accounted for more
than 0.1% of the dissolved REEs while all other complexes (sulfate, hydroxyl, chlOride, and
fluoride) and the free metal ion species were predicted to be negligible (Johannesson et al, 1996).
A study developed in 200 Canadian agricultural soils (Sheppard et al., 2009) showed solid-water
partition coefficient (Kd) values for REE between 3800 and 8100 L/kg in contrast to Kd values for
other metals and metalloids (Zn, Cd, Cu, Cr and As) between 16 and 780 L/kg, showing that a
high proportion of REEs are bound to soil in the environment (Sheppard et al, 2009).
Due to the relatively large Kd values, the potential transport of REEs from the TMS is likely to be
slower than for other already rnonitored constituents that are present in the TMS at much higher
concentrations. Uranium is expected to be more mobile than the REEs and would be detected
sooner in any potential seepage from the TMS. As a result, there is no need to add any of the REEs
Letter to Ty L. Howard
September 9, 2020
Page 17 of 41
as monitoring constituents under the GWDP because of Ore or similar natural monazite sand ore
processing.
Indicator Parameters. It should also be noted that chloride, fluoride and sulfate are more mobile
than any of the foregoing metals and are the best indicator parameters of any potential TMS
seepage. As a result, even if any of the constituents analyzed above were not adequately
represented in the GWDP by similar metals or other constituents, any potential seepage from the
TMS would be adequately monitored by these indicator parameters, because they would all be
expected to reach the points of compliance much sooner than any of the metals or other
constituents.
Conclusion
The evaluation above addresses the expected composition of tailings and the chemical and
environmental behavior of the tailings from the introduction of Ore and similar natural monazite
sand ores into the TMS, and considers whether any potential new constituents need to be included
in the GWDP as a result of processing Ore and similar natural monazite sand ores at the Mill.
Table 4 summarizes the anticipated composition of the tailings solution after processing Ore and
similar natural monazite sand ores. The most appreciable change in concentration from processing
Ore and similar natural monazite sand ores will result from barium and zirconium. Although to a
much lesser degree, noticeable changes in lead, gallium, hafnium, natural thorium and certain
REEs are also expected.
In all cases, our conclusion is that:
• polymeric materials such as PVC and HDPE are selected for geomembrane liners
specifically because they are resistant to solutions of metals and metal salts, like barium,
zirconium, lead, gallium, hafnium, natural thorium and REEs in all proportions (USEPA
1988), and, as a result, the introduction of those constituents into the TMS from processing
Ore is not a concern. Nor would there be a concern if the concentrations of those
constituents were higher or the quantity of the Ore and similar natural monazite sand ores
were higher than the amount assumed for this analysis; and
lead is already a monitored constituent under the GWDP, and each of the other constituents
is well-represented by other constituents which are already analyzed under the GWDP. As
a result, there is no need to add any of these constituents as monitoring constituents under
the GWDP because of Ore and similar natural monazite sand ore processing.
The conclusions above would apply equally to higher quantities of Ore or similar natural monazite
sand ores than the 15,000 tons assumed in the analysis, such as double that amount to 30,000 tons
of Ore or similar natural monazite sand ores per year. The only other metals that would show any
noticeable increase in tailings if the quantity of Ore or other similar natural monazite sand ores
were doubled to 30,000 tons per year are calcium, manganese, and nickel. All are metals which
have been introduced to the TMS with other natural ores and/or previously approved alternate feed
materials. Calcium, manganese, and nickel are known to be present in natural ores. Like other
Letter to Ty L. Howard
September 9, 2020
Page 18 of 41
metals, calcium, manganese and nickel are inert to the tailings liner materials at all proportions
and quantities. Calcium, manganese and nickel are monitored in the Mill's groundwater
monitoring program.
References for Presence of REEs in Other Uranium Ores
Della Valle, R.S. and D.G. Brookins, 1984 Samples from the Grants Mineral Belt, New Mexico —
Trace Element Distributions in Sedirnentary-Type Uranium Deposits.
Green 2019. Jeffrey A. Green The Collapse of American Rare Earth Mining — and Lessons
Learned. Defense News November 12, 2019
IAEA 2018 Uranium Resources as Co- and By-Products of Cometallic, Base, Rare Earth, and
Precious Metal Ore Deposits. International Atomic Energy Agency TECDOC 1849
Mercadier 2011. Mercadier, Julien, Cuney, Michel, Lach, Phillipe, et.al Origin of Uranium
Deposits Revealed by Their Rare Earth Signature. U. of Nancy, published in Terra Nova 2011
King, Hobat M. PhD, PG 2018 REE-Rare Earth Elements and Their Uses www.geology.com,
accessed on September 2, 2020
NAS 1986. Scientific Basis for Risk Assessment and Management of Uranium Mill Tailings
National Academy of Sciences, 1986
Olson, J.C, et. al. 1954 Rare Earth Mineral Deposits of the Mountain Pass District San
Bernardino County, California. US Geological Survey
Sax, Irving J. and Richard Lewis 1987 Hawley's Condensed Chemical Dictionary Eleventh
Edition Van Nostrand Reinhold Co., New York 1987
USEPA 1982. Final Environmental Impact Statement for Selected Active and Inactive Uranium
Mill Tailings Sites US Environmental Protection Agency 520/4-82 013-1 October 1982
US EPA, 1988. Risk Reduction Engineering Laboratory. Lining of Waste Containment and Other
Impoundment Facilities EPA/600/2-88/052 September 1988
USGS 2017 Van Gosen, Bradley S., Philip L.VerPlanck et.al. Critical Mineral Resources of the
United States—Economic and Environmental Geology and Prospects for Future Supply, Rare
Earth Elements USGS Paper 1802-0
Van Gosen, B.S. 2020 Geochemical and Xray Diffraction Analysis of Drilling Core Samples
from the Canyon Uranium Deposit — A Solution Collapse Breccia Pipe
Letter to Ty L. Howard
September 9, 2020
Page 19 of 41
References for Natural Thoriutn and Thorium-230 in Natural Ores
NRCP (National Council on Radiation Protection and Measurements) 1993. Report N. 118.
Radiation Protection in the Mineral Extraction Industry, November 3.0, 1993.
Cardarelli, John 1999. "Attachment 1- Occupational Exposure Assessment Modeling". URL:
http://www.nifc.gov/policies/red book/doc/RadiationDocurnent.pdf. Referenced in N1FC
(National hnerageney Fire Center) Interagency Standards for Fire and Fire Aviation Operations.
January 2012.)
Abdelouas, A. 2006. "Uranium Mill Tailings: Geochemistry, Mineralogy, and Environmental
Impact," in Elements, Vol. 2, pp. 335-341. December 2006. URL:
httrilgnews.wust1.edule1ements/e2 6/e2 6 art abdelOuas.pdf.)
CanMet 1977. Industrial Hygiene Survey; Uranium Mining and Milling. Prepared for Canadian
Minerals and Energy Technology (CanMet). James F. MacLaren Limited, 1977.
References for Chemical Behavior of REEs
Ayora, C., Macias, F., Torres, F., and Nieto, J.M., 2015, Rare earth elements in acid mine drainage,
in Nieto, J.M., R., P.L., A., S., Cánovas, C.R., and Macias, E, eds., Los elementos de las Tierras
Raras, Volume 12: Seminarios SEM: Madrid, Sociedad Espaiiola de Mineralogia, p. 92-107.
Brookins, D.G., 1989, Aqueous geochemištry of rare earth elements: Reviews in Mineralogy and
Geochemistry, v. 21(1), p. 201-225.
Bruque, S., Mozas, T., and Rodriguez, A., 1980, Factors influencing retention of lanthanide ions
by montmorillonite: Clay Minerals, v. 15(4), p. 413-420.
Byrne, R.H., and Kim, K.-H„ 1993, Rare earth precipitation and coprecipitation behavior: The
limiting role of po43- on dissolved rare earth concentrations in seawater: Geochimica et
Cosmochimica Acta, v. 57(3), p. 519-526.
Chevis, D.A., Johannesson, K.H., Burdige, DJ., Tang, J ., Bradley Moran, S., and Kelly, R.P.,
2015, Submarine groundwater discharge of rare earth elements to a tidally-mixed estuary in
southern Rhode Island: Chemical Geology, v. 397, p. 128-142.
Coppin, F., Berger, G., Bauer, A., Castet, S., and Loubet, M., 2002, Sorption of lanthanides on
smectite and kaolinite: Chemical Geology, v. 182(1), p, 57-68.
Dia, A., Gruau, G., Olivié-Lauquet, G., Riou, C.. Molénat, J., and Curmi, P., 2000, The distribution
of rare earth elements in groundwaters: Assessing the role of source-rock composition, redox
changes and colloidal particles: Geochimica et Cosmochimica Acta, v. 64(24), p. 4131-4151.
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September 9, 2020
Page 20 of 41
Gimeno Serrano, M.A.J., Auqué Sanz, L.F., and Nordstrom, D.K., 2000, REE speciation in low-
temperature acidic waters and the competitive effects of aluminum: Chemical Geology, v. 165(3),
p. 167-180.
Gosselin, D.C., Smith, M.R., Lepel, E.A., and Laul, J.C., 1992, Rare earth elements in chloride-
rich groundwater, Palo Duro basin, Texas, USA: Geochimica et Cosmochimica Acta, v. 56(4), p.
1495-1505.
Goyne, K.W., Brantley, S.L., and Chorover, J., 2010, Rare earth element release from phosphate
minerals in the presence of organic acids: Chemical Geology, v. 278(1), p. 1-14.
Hannigan, R.E., and Sholkovitz, E.R., 2001, The development of middle rare earth element
enrichments in freshwaters: Weathering of phosphate minerals: Chemical Geology, v. 175(3), p.
495-508.
Jensen, H.J, 2017, The Mobility of Two Emerging Contaminants, allium and Indium, in the Soil-
Plant System. Dissertation, Lincoln University, Christchurch, New Zealand.
Johannesson, K.H., and Xiaoping, Z., 1997, Geochemistry of the rare earth elements in natural
terrestrial waters: A review of what is currently known: Chinese Journal of Geochemistry, v. 16(1),
p. 20-42.
Johannesson, K.H., Lyons, W.B., Stetzenbach, K.J., and Byrne, R.H., 1995, The solubility control
of rare earth elements in natural terrestrial waters and the significance of P043- and C032- in
limiting dissolved rare earth concentrations: A review of recent information: Aquatic
Geochemistry, v. 1(2), p. 157-173.
Johannesson, K.H., Stetzenbach, K.J., Hodge, V.F., and Berry Lyons, W., 1996, Rare earth
element complexation behavior in circumneutral pH groundwaters: Assessing the role of carbonate
and phosphate ions: Earth and Planetary Science Letters, v. 139(1), p. 305-319.
Liu, H., Guo, H., Pourret, O., Chen, Y., and Yuan, R., 2019, Role of manganese oxyhydroxides in
the transport of rare earth elements along a groundwater flow path: International Journal of
Environmental Research and Public Health, v. 16(13), p. 2263.
Liu, H., Pourret, O., Guo, H., and Bonhoure, J., 2017, Rare earth elements sorption to iron
oxyhydroxide: Model development and application to groundwater: Applied Geochemistry, v. 87,
p. 158-166.
Maza-Rodriguez, J., Olivera-Pastor, P., Bruque, S., and Jimenez-Lopez, A., 1992, Exchange
selectivity of lanthanide ions in montmorillonite: Clay Minerals, v. 27(1), p. 81-89.
Millero, F.J., 1992, Stability constants for the formation of rare earth-inorganic complexes as a
function of ionic strength: Geochimica et Cosmochimica Acta, v. 56(8), p. 3123-3132.
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September 9, 2020
Page 21 of 41
Noack, C.W., Dzombak, D.A., and Karamalidis, A.K., 2014, Rare earth element distributions and
trends in natural waters with a focus on groundwater: Environmental Science & Technology, v.
48(8), p. 4317-4326.
Olfas, M., Canovas, C.R., Basallote, M.D., and Lozano, A., 2018, Geochemical behaviour of rare
earth elements (REE) along a river reach receiving inputs of acid mine drainage: Chemical
Geology, v. 493, p. 468-47'7.
Sheppard, S., Long, J., Sanipelli, B., and Sohlenius, G., 2009, Solid/liquid partition coefficients
(Kd) for selected soils and sediments at Forsmark and Laxemar-Simpevarp: Svensk
Karnbränslehantering AB, SKB Rapport R-09-2'7, 72 p.
Sheppard, S., Long, J., Sohlenius, G., Lars-Gunnar, O., Borgiel M., Grolander F., and Norden S.,
2011, Solid/liquid partition coefficients (Kd) and Plant/Soil Concentration Ratios (CR) for
Selected Soils, Tills and Sediments at Forsmark R-11-24, 77 p.
verplanck, P.L., Nordstrom, D.K., and Taylor, I-LE., 1999, Overview of rare earth element
investigations in acid waters of U. S. Geological survey abandoned mine lands watersheds, U.S.
Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting,
Charleston, South Carolina: U.S. Geological Survey Water-Resources Investigations Report 99-
4018A, p. 83-92.
Wood, S.A., 1990, The aqueous geochemistry of the rare-earth elements and yttriurn: 1. Review
of available low-temperature data for inorganic complexes and the inorganic ree speciation of
natural waters: Chemical Geology, v. 82, p. 159-186.
DWMRC COMMENT
RAI 3 — Additional information is needed regarding changes or additions that may be required
in the uranium extraction circuits
It is unclear in the information submitted where in the process the rare earth minerals would be
extracted, and what physical alterations to the mill works would be necessary. Please describe
changes necessary to the plant and the processes. If no changes are needed, please explain/justify
why not.
EFRI RESPONSE:
Product to be Produced
The Mill will process the Ore (and similar natural monazite sand ores) to recover uranium and an
REE Concentrate. The recovered uranium will be sold into the nuclear fuel cycle in the same
manner as other uranium produced at the Mill. The REE Concentrate produced at the Mill will be
a carbonate that generally contains most of the REEs. The Mill will sell its REE Concentrate
to REE separation facilities, where the individual REEs will be separated into individual REE
oxides. Those individual REE oxides will then be provided by the separation facility to various
Letter to Ty L. Howard
September 9, 2020
Page 22 of 41
end users. For example: neodymium is used to make magnets, which are used in electric motors
and sound speakers; yttrium is used in making electrical sensors; catalytic converters use cerium
oxides; phosphors in optical displays contain yttrium, europium and terbium oxides; and modern
media and comrnunication devices — cell phones, televisions, and computers -- all employ REEs
as magnets for speakers and hard drives and phosphors for optical displays. In some cases the
REE Concentrate produced by the Mill will be separated at a separation facility into groups of
REEs, such as into light REEs (lanthanum, cerium, praseodymium, neodymium, promethium,
samarium and scandium) and heavy REEs (yttrium, europium, gadolinium, terbium, dysprosium,
holmium, erbium thulium, ytterbium and lutetium) as an intermediate product, for shipment to
other facilities, depending on the needs and capabilities of the other facilities, to be separated into
actual REEs at those other facilities.
The REE Concentrate that the Mill will produce can be sold in either a dewatered form
(approximately 20% moisture content) or in a dry form (approximately 1% moisture content). The
Mill currently plans to produce and sell its REE Concentrate in a dewatered form, not a dry form.
The currently planned process, which includes dewatering of the REE precipitate, utilizes existing
or similar equipment in the same manner it is or could be used for comparable ores and alternate
feed materials, involves no air emissions, and will not require any actions under the Mill's existing
Air Approval Order. However, the Mill may consider in the future producing all or a portion of
its REE Concentrate in a dry form and will evaluate at that time whether any actions under its Air
Approval Order may be required in order to dry the REE Concentrate.
Similarly, the Mill may consider in the future performing all or some of the steps required to
separate at the Mill individual REEs or groups of REEs from the Mill's REE Concentrate, to
produce final or intermediate REE products. Should the Mill decide to go down that path, it would
evaluate at that time what if any license or permit amendments or regulatory approvals may be
required.
At this time however, the Mill plans to produce only a commercially salable dewatered REE
Concentrate.
Process Description
A process description of the uranium and potential REE Concentrate recovery circuits for Ore and
similar natural monazite sand ores at the Mill is provided below. As typical for any new ore or
alternate feed material, the Mill is currently in the process of optimizing arid finalizing the process
steps for the Ore and other rnonazited sands. A generalized schematic flow diagram is provided
as Figure 1. The description below and flow schematic represent a potential generic process
sequence and configuration. The final process sequence is expected to fall within the envelope of
conditions discussed below.
The Ore or similar natural monazite sand ore may be ground via the grizzly and SAG mill, or may
be introduced directly into the leach tanks, and once entered into the leach tanks treated ("cracked")
with sodium hydroxide ("NaOH"). To crack the Ore or similar monazite sand ore, NaOH would
be added to the Ore or other monazite sand ore and it would be heated in solution to break down
Letter to Ty L. Howard
September 9, 2020
Page 23 of 41
the mineral phosphates, converting them to hydroxides. The solutions would be transferred to a
caustic recovery step. Recovered caustic solutions would be returned to the "cracking" step. The
Ore or similar natural monazite sand ore would then be washed and the solids would be transferred
to the leaching step where they would be leached in hydrochloric acid ("HC1") to solubilize the
REEs. Tri-sodium phosphate, the byproduct of the caustic recovery, would be discharged to
tailings. The Mill already stores and uses tri-sodium phosphate, as well as phosphoric acid, and
has introduced phosphate to the TMS over its operating history with no harmful effects.
Phosphate, like the other oxygenated anions already present at elevated levels in the TMS and
monitored in the TMS and groundwater monitoring program (e.g., sulfate and carbonate), is inert
relative to the tailings liner materials. Sodium, as evident in the annual tailings monitoring data,
is present in the TMS at times up to 4% or greater, and is also monitored in the groundwater
monitoring program.
Following HCI leaching, sodium sulfate ("Na2SO4") would be added, along with barium chloride
("BaC12") to precipitate radium. The solids would be washed, and the liquid fraction would then
be precipitated with sodium carbonate. The rare earth solutions would then be precipitated with
sodium carbonate, and dewatered using the Mill's centrifuges or similar equipment, and then
packaged. Alternatively, the Mill may evaluate in the future drying the precipitates with low
temperature in one of the Mill's existing vanadium dryers or potentially in one or more vacuum
dxyers that would be installed. Although this drying alternative is not currently planned, and drying
is not necessary to produce a salable product, if this alternative is pursued in the future, the Mill
would evaluate whether or not any notices or amendments to the Mill's Air Approval Order would
be required at that time.
The solids left after the HC1 leach would be transferred to the normal uranium circuit for sulfuric
acid leaching of uranium. The uranium stream would follow the normal uranium solvent
extraction, precipitation and calcining/drying and packaging process used for other uranium ores.
The thorium would remain in solution and be disposed of in the TMS.
Alternatively, the Mill may determine that the Ore or similar natural monazite sand ore may be
acid leached without caustic cracking. This would mean that the Ore or similar natural monazite
sand ore would not need to undergo grinding, and would be directly acid leached. In that scenario,
no caustic addition would be required.
Reagents to be Used
The REE process will primarily use reagents which are already used in the Mill for processing
conventional ores: Na2SO4, soda ash, and NaOH. Following NaOH treatment of the Ore or similar
natural monazite sand ore, if that step is necessary, the Mill plans to leach the REEs from the Ore
or other monazite sands with an HC1 leach. Although the Mill doesn't currently use HC1 for
leaching, HC1 has historically been present in the Mill and is present in the TMS. The Mill has
processed a number of alternate feed materials with elevated chloride content, such as Molycorp
material, in the acid leach circuit. As soon as those feed materials are introduced into the sulfuric
acid leach circuit, chloride ion is converted to HC1 and is eventually discharged with other non-
Letter to Ty L. Howard
September 9, 2020
Page 24 of 41
uranium constituents to tailings. Chloride ion is also introduced into the TMS from the use of
sodium chloride and sodium chlorate, in other parts of the Mill.
Analyses from the annual tailings solution sampling, ranging from several thousand mg/kg up to
1 0, 100 mg/kg (1%) in Cell 4A, or up to 1 15,000 mg/kg ( 1 1 %) chloride in Cell 3, demonstrate the
Mill has processed and discharged, and the TMS has received and handled, appreciable levels of
chloride, much of it in the form of HC1, with no detrimental effects.
The uranium circuit will be unchanged and will use the same reagents as the Mill uses for other
ores.
Minimal Equipment Changes
Minimal equipment changes or adjustments would be required.
The Mill anticipates adding an additional storage tank and bermed tank area on site to store HC1.
BaC12 and NaOH (if it is to be used in dry form) will likely be stored in 25Kg bags at the appropriate
locations on site. Storage tanks and mixing systems for sodium hydroxide solutions already exist
on site. Dewatering will be accomplished using the Mill's centrifuges currently used for vanadium
and uranium dewatering, or new centrifuges which could also be used for uranium and vanadium
production, or the Mill may use an existing or new filter press or roller press for that purpose.
As mentioned above, the Mill plans to dewater the REE precipitates, and not dry them. However,
should the Mill decide in the future to dry the REE precipitates, minimal equipment changes or
adjustments would be required. REE drying requires lower temperatures and less energy input
than conventional drying. Should the Mill decide to dry the REE precipitates, the Mill would
likely either use one of its existing vanadium dryers and vanadium packaging system or install one
or more vacuum dryers to dry the precipitated REE Concentrate, which would have their own self-
contained packaging systems.
If the Mill were to use one of the existing permitted dryer and air pollution control systems from
the vanadium area, it would be heated by existing burners and fuel supply in the same manner as
for vanadium drying. REE drying at anticipated production rates is expected to require lower air
flow and lower temperature than anticipated in the Mill's Air Approval Order for any of the
vanadium dryers at approved vanadium production rates. Similarly, under this alternative, the
vanadium packaging system and packaging baghouse stack would be utilized.
Unlike the Mill's current dryers and packaging systems, if a vacuum dryer system were to be
installed, it would not use direct fired heating (no open-hearth burners), and neither the dryers nor
the packaging system would exhaust combustion gases to the atmosphere (no process emissions
stacks). Combustion gases from the heating source would be exhausted where the steam or indirect
heating fluid is heated, and the vacuum dryers would utilize existing Mill heating sources. A
typical vacuum dyer loop and packaging system would contain:
Indirect pre-heating: (heating steam or other indirect heat source)
Letter to Ty L. Howard
September 9, 2020
Page 25 of 41
• Rotary vacuum dryer;
• Vapor treatment or recovery: High Efficiency Particulate Air ("HEPA") bag filter, water
scrubber, and vapor condenser;
• Cooling water for vacuum pump sealant water; and
• Packaging equipment, controlled by the same vacuum system and vapor treatment as the
dryer.
As mentioned above, drying is not required to produce a salable product, so the Mill currently
plans to dewater, not dry, the REE precipitate, and then package the dewatered precipitate for
transport to an REE separation facility. Should the Mill decide to dry the REE precipitate in the
future, it would evaluate at that time whether or not any actions under its Air Approval Order may
be required.
Standard Operating Procedures
The Mill will amend its existing Standard Operating Procedures ("SOPs") and adopt any new
SOPs that may be required in connection with the foregoing process changes and adjustments.
The process changes and adjustments described above, and any changes to existing SOPs and
adoption of any new SOPs fall within the range of normal process change activities that are
reviewed and approved by the Mill's Safety and Environmental Review Panel ("SERP") on a
routine basis. The Mill plans to have its SERP review and approve all such process changes,
adjustments, revised SOPs and new SOPs prior to commencement of each of the applicable Ore
receipt, handling, storage, processing, drying packaging and disposal activities.
Air Approval Order
The currently planned process, which includes dewatering the REE precipitate, utilizes existing or
similar equipment in the same manner it is or could be used for comparable ores and alternate feed
materials, involves no air emissions, and does not involve: (a) constructing any new installations
which will or might reasonably be expected to become a source or an indirect source of air
pollution; (b) making any modifications to or relocating any existing installations which will or
might reasonably be expected to increase the amount of, or change the effect of, or the character
of, air pollutants discharged, so that any such installation may be expected to become a source or
indirect source of air pollution, or (c) installing any control apparatus or other equipment intended
to control emissions of air pollutants. As a result, no notifications, approvals or amendments are
required under the Mill's existing Air Approval Order for the production of a dewatered REE
Concentrate at the Mill.
Should the Mill decide to evaluate drying the REE precipitate at the Mill in the future, the
following factors would be relevant. The Mill anticipates having sufficient steam production
capacity within its existing boilers on site to provide pre-heating for one of the existing vanadium
dryers, or a vacuum dryer, without new combustion equipment. If the Mill uses one of the existing
permitted vanadium dryers and the existing vanadium scrubber system, all air emissions from the
dryer would be addressed by the vanadium scrubber system, in the same manner as for vanadium
Letter to Ty L. Howard
September 9, 2020
Page 26 ot' 41
drying, and the vanadiurn packaging systern and packaging baghouse stack would be utilized to
address any air emissions from packaging. In the case of vacuum drying, moisture and vapors
removed by the vacuum dryers would not be exhausted to air, but would be vented into one or
more of the particulate control equipment items identified as "vapor treatment or recovery," above.
For either drying option, EFRI would evaluate whether any changes to the Mill's air emission
inventory or Air Approval Order would be required, based on the configuration and throughput
rate ultimately selected for the dryer, packaging, and air pollution control system, and would
provide any required notices or requests for approval to the Utah Division of Air Quality on a
timely basis.
DWMRC COMMENT
RAI 4 — Additional information for compliance with U.S. Department of Transportation
requirements
On June 26, 2020 in an email request, the Division. requested to see an old manifest of the monazite
sand material when it was being sent to China. After reviewing both the letter of June 25, 2020
and the manifest.please provide the following information:
11308
• .The manliest provided listed the "chemical form" as monazite sand. This is not a chemical
form description according to .U.S. Department of Transportation. please provide the
correct chemical form for the uranium/rare earth nzineral ore. (i.e. U308 other appropriate
chemical descriptions).
• in the EFRI's letter it states that Supersacks in intermodal containers will be used to
transport the uranium ore to the Mill. Pleaseprovide information. that the Supersacks and
intermodal containers are IP-1 containers which are the appropriate tran.sport containers
for LSA-.1 material.
• PleaSe indicate the shipment of the uranium/rare earth nzineral ore will be exclusive use
shipments.
• Please provide a detailed description of transportation route(s) that will be used to
transport the ore to the Mill.
9 Please update the transportation emergency response plan to include the transportation of
ate uranium/rare earth mineral ore from Georgia to the Mill.
• Please provide a description of all other transportation requirements regarding labeling,
placarding, transportation papers, etc.
Letter to Ty L. Howard
September 9, 2020
Page 27 of 41
EFRI RESPONSE:
Shipments of Ore to the Mill
The following discussion addresses how the Ore will be shipped to the Mill. It is expected that if
any other natural monazite sand ores are to be shipped to the Mill, similar transportation factors
would apply.
Manifest. Chemours may ship the Ore either by rail in inter-modal containers ("IMCs") or other
LSA-1 approved containers or by truck, as discussed below. For the purposes of U.S. Department
of Transportation ("DOT") documentation, the Ore will be labeled with chemical form "Natural
Uranium (U-nat) and Natural Thorium (Th-nat)." EFRI will work with Chemours to ensure the
Ore is properly labeled on the manifest and other shipping documentation.
IP-1 Containers to be Used. The Ore will be shipped as Radioactive LSA-1 (low specific activity)
Hazardous Material as defined by DOT regulations. Chemours will ship the Ore in Supersacks
that meet IP-1 packaging requirements and are appropriate for LSA-1 Class 7 material. Whether
the Ore is shipped in 1MCs or other LSA-1 approved containers or by trucks, the IMCs, other LSA-
1 approved containers or trucks will be suitable containers for LSA-1 Hazardous Material. The
IMCs or other LSA-1 approved containers will provide secondary containment to prevent any
breaches of the Supersacks.
Exclusive Use ShipinentS. Each shipment will be "exclusive use" (i.e., the only material on each
vehicle, IMC or other LSA-1 approved container will be the Ore, unless and until the vehicle, 1MC
or other LSA-1 approved container is decontaminated for free release in accordance with
applicable Mill procedures).
Transportation Routes. Chemours may ship the Ore by either of the following methods. Chemours
would load the Ore Supersacks into IMCs or other LSA-1 approved containers at its Offerman site.
Chemours' transportation contractor would load the IMCs or other LSA-1 approved containers
onto rail cars at the railhead at the Offerman site. The IMCs or other LSA-1 approved containers
would be transported by rail to one of the existing rail transfer yards in Utah (e.g., Crescent
Junction or Green River), followed by transfer to intermodal truck tractors from the railhead to the
Mill. The Ore would be hauled by truck along U.S. Highway 191 to the Mill.
Alternatively, the Ore Supersacks may be loaded onto trucks at the Offerman Site. The trucks
would travel via surface roads to 1-95 and north along 1-95 to 1-40. They would follow 1-40 to
Albuquerque, then use surface roads from 1-40 to the Mill. The route may vary depending on road
conditions and weather.
At full capacity, the Mill receives and processes approximately 2,000 tons of ore per day, or up to
720,000 tons of ore per year. 15,000 tons of Ore or similar natural monazite sand ore per year, or
double that amount, would be an insignificant portion of the Mill truck traffic when the Mill is in
Letter to Ty L. Howard
September 9, 2020
Page 28 of 41
full operation. and no impacts to local traffic over and above those already contemplated for normal
Mill truck traffic are expected.
Transportation Emergency Response Plan. Chemours' transportation contractor has an
Emergency Response Action Plan ("ERAP") in place for the Ore. The ERAP will be adapted
based on the transportation method (road or rail) chosen.
As discussed above under EFR1's response to RAI 2, the Ore has a uranium content comparable
to Colorado Plateau ores and a natural thorium content comparable to previously approved
alternate feed materials (e.g., Sequoyah Fuels), and contains no additional constituents of any
significance beyond those associated with other ores or alternate feed materials previously
transported to the Mill. Therefore, the Ore poses no additional hazards during transport above
previously licensed activities. Existing accident response and spill response procedures are
therefore sufficient for management of potential transportation accidents or spills of the Ore.
Marking. Labeling and Placarding. Chemours will arrange with its transportation contractor for
the proper marking, labeling, placarding, manifesting and transport of each shipment of Ore. Each
shipment or container will include:
• Bill of lading;
•• Safety Data Sheet;
• DOT Emergency Response Plan (Spill Guide);
• Radiological Release Form (from the Chemours site);
• Packing List;
• Emergency Contact Information;
• Route Instructions; and
• Placard/Labeling as UN2912 Radioactive 7.
Shipments will be tracked by the transportation contractor from the Offerman plant until they reach
the Mill.
Sldpoients of REE Concentrate from the Mill.
Manifest. The Mill will ship its REE Concentrate in enclosed sea containers by truck to a seaport,
likely Seattle, San Francisco or Houston, depending on• whether or not the REE Concentrate will
be shipped to Asia or Europe, or alternatively to a point of final destination in North America, or
by truck part way and by rail for the remainder of the distance. For the purposes of DOT
documentation, the REE Concentrate will be labeled with chemical form "Rare Earth Carbonate."
IP-1 Containers to be Used. The dewatered REE Concentrate will be shipped according to DOT
regulations. The Mill will ship the dewatered REE Concentrate in Supersacks that meet IP-1
packaging requirements with an inner plastic sealed liner, or in sealed 55-gallon drums or other
sealed containers. The containers will meet DOT shipping standards. The enclosed sea containers
will provide secondary containment and protect the Supersacks from breach. The shipment of
dewatered metal product without drying has previously been evaluated for the Mill. The original
Letter to Ty L. Howard
September 9, 2020
Page 29 of 41
1978 Environmental Report for the Mill contemplated that from certain ores, the Mill would
produce and ship a moist filter cake of copper that would be transported to an offsite facility for
drying.
Not Exclusive Use Shipinentg. Each shipment of REE Concentrate will be free-released from the
Mill and will not be "exclusive use".
Transportation Routes. The lined Supersacks, drums or other sealed containers will be loaded into
enclosed sea containers at the Mill and shipped by truck on Highway 191 either north to 1-70 or
south on public roads to 1-40 to the seaport or final destination, or may be transferred to rail at
some point along the route.
At full capacity, the Mill receives and processes approximately 2,000 tons of ore per day, or up to
720,000 tons of ore per year. The REE Concentrate produced from 15,000 tons of Ore and similar
natural monazite sand ore per year, or double that amount, would be an insignificant portion of the
Mill truck traffic when the Mill is in full operation, and no impacts to local traffic over and above
those already contemplated for normal Mill truck traffic are expected. Likewise, the REE
Concentrate would be an immeasurably small addition to regional rail freight if a segment of its
transport involved rail.
Transportation Emergencv Response Plan. The Mill's transportation contractor will have an
Emergency Response Action Plan ("ERAP") in place for the REE Concentrate. The ERAP will
be adapted based on the transportation method (road or road/rail) chosen.
Marking. Labeling and Placarding. The Mill will arrange with its transportation contractor for the
proper marking, labeling, placarding, manifesting and transport of each shipment of REE
Concentrate. Each shipment or container will include:
• Bill of lading;
• Safety Data Sheet;
• DOT Emergency Response Plan (Spill Guide);
• Radiological Release Form (from the Mill);
• Packing List;
• Emergency Contact Information;
• Route Instructions;
• Labeling with shipper information and content on each drum or bag; and
• Placard/Labeling as required by DOT.
Shipments will be tracked by the transportation contractor from the Mill until they reach their final
destination.
Letter to Ty L. Howard
September 9, 2020
Page 30 of 41
DWMRC COMMENT
RAI 5 — Assess the Radiological and Non-radiological effects of processing uranium ore with
rare earth minerals
From the 1978 Environmental Report for the White Mesa Uranium Project, Section 1.0 Proposed
Activities, it states "Energy Fuels Nuclear, Inc. proposes to construct and operate an acid leach
uranium mill-and associated facilities for producing yelloweake uranium concentrate and, when
economically feasible, limited quantities of copper and/or 'vanadium concentrates." In EFRI's
June 25, 2020 letter, it proposes to process a uranium ore for yellowcake uranium concentrate
and a rare earth mineral concentrate. The process of extracting a rare earth mineral concentrate.
has not been environmentally evatuated for the White Mesa Uranium Mill.
Please evaluate the radiologicaland non,radiological effects of processing a uranitan ore with
rare earth minerals. Please include occUpational and public exposure and short and; long-term
effects of processing uranium ore with rare earth minerals.
Please discuss any adjustments needed to the radiation safety program, environmental monitoring
program and groundwater monitoring to process the ore. If no changes are needed, please
explain/justify why not.
EFRI RESPONSE:
All the Material Processes Applicable to Extracting an REE Concentrate at the Mill have
Previously been Environmentally Evaluated.
The Mill is A licensed uranium processing facility that has •processed to date over 5,000,000 tons
of uranium-bearing conventionally mined ores and alternate feed materials mainly for the recovery
of uranium and vanadium, and is also licensed to recover and has recovered tantalum and niobium
(from the Cabot alternate feed materials), in all cases with the resulting tailings being permanently
disposed of as 1 1 e.(2) byproduct material in the Mill's TMS. Environmental impacts associated
with such previously licensed Mill operations have been thoroughly evaluated and documented in
the past. See, for example:
• the original 1979 Final Environmental Statement ("FES") for the Mill;
▪ Environmental Assessments ("EAs"), dated 1985 and 1997;
• an EA for the Mill's reclamation plan dated 2000;
• EAs for alternate feed materials dated 2001 and 2002, in each case prepared by the NRC;
• the Safety Evaluation Report for the Receipt, Storage and Processing of FMR1 Alternate
Feed Material prepared by DWMRC;
• the Safety Evaluation Report for the Receipt, Storage and Processing of Dawn Mining
Alternate Feed Material prepared by DWMRC;
• the Safety Evaluation Report for the Receipt, Storage and Processing of Sequoyah Fuels
Alternate Feed Material prepared by DWMRC; and
Letter to Ty L. Howard
September 9, 2020
Page 31 of 41
The Technical Evaluation and Environmental Assessment Report prepared in connection
with the 2018 Radioactive Materials License Renewal for the Mill, prepared by DWMRC.
The Ore or similar natural monazite sand ore will be processed at the Mill for the recovery of
uranium and an REE Concentrate and the resulting tailings will be permanently disposed of in the
Mill's tailings impoundments as 1 le.(2) byproduct material, in a similar fashion as other
conventionally mined ores and alternate feed materials that have been processed or licensed for
processing at the Mill.
Accordingly, the discussion below will focus on the various pathways for potential radiological
and non-radiological impacts on public health, safety and the environment and determine if the
receipt and processing of the Ore or similar natural monazite sand ores would result in any potential
significant incremental impacts over and above previously licensed activities.
Potential effects on existing tailings or the TMS, and potential impacts on groundwater were
discussed in the response to RAI 2, above. The pathways that are analyzed in the discussion below
are the following:
a) potential impacts from transportation of the Ore or similar natural monazite sand
ores to the Mill;
b) potential impacts from radiation released from the Ore or similar natural monazite
sand ores while in storage at the Mill;
c) any chemical reactions that may occur in the Mill's process;
d) potential impacts on surface water;
e) potential airborne radiologic impacts;
0 potential radon and gamma impacts; and
g) worker health and safety issues.
These potential pathways will be discussed in the following sections of this letter.
The findings below will demonstrate that, because all the constituents in the Ore have either been
reported to be, or can be assumed to be, already present in the Mill's TMS or were reported in other
conventional ores or licensed alternate feed materials, at levels generally comparable to or higher
than those reported in the Ore, the resulting tailings will not be significantly different from existing
tailings at the facility, and the impacts from the foregoing pathways will not be significantly
different from the Ore or similar natural monazite sand ores than from other conventional ores and
licensed alternate feed materials. Consequently, there will be no incremental public health, safety
or environmental impacts over and above previously licensed activities. As a result, although not
expressly evaluated in previous analyses, the process of extracting an REE Concentrate has in fact
been environmentally evaluated for the Mill, through the evaluation of similar activities.
Letter to Ty L. Howard
September 9, 2020
Page 32 of 41
The radiological and non-radiological effects of processing a uranium ore with rare earth
minerals
Occupational Exposure — Anal vsiR of any Radiological Effects. The uranium concentration, which
will generally be in equilibrium with its daughters because the Ore has not been chemically altered
in any way, is comparable to a typical Colorado Plateau uranium or uranium/vanadium ore, and
significantly less than a typical Arizona Strip ore. As a result, occupational exposures from
uranium and its daughters associated with processing the Ore and similar natural monazite sand
ores will not be any different from occupational exposures from Colorado Plateau ores, and will
easily be addressed within the Mill's normal radiation protection SOPs.
The natural thorium concentration in the Ore, which is also expected to generally be in equilibrium
with its daughters because the Ore has not been chemically altered in any way, is higher than for
Colorado Plateau and Arizona Strip ores, but well within the concentrations of natural thorium
contained in previously licensed alternate feed materials. Specifically, it is comparable to the
natural thorium concentrations contained in the Sequoyah Fuels alternate feed materials, which
have been successfully and safely received and processed at the Mill, and well below the natural
thorium concentrations in the W.R Grace alternate feed materials, which were licensed for
processing at the Mill but never received or processed, for commercial reasons. The Mill maintains
in place, and updates from time-to-time, a "High Thorium Content Ore Management" SOP for
handling ores and feed materials with elevated levels of thorium, which was originally
implemented in connection with the approval of the W.R. Grace alternate feed material license
amendment, and was approved by the NRC. The applicable provisions of that SOP are adapted to
prepare feed-specific SOPs for any ores and alternate feed materials with elevated levels of
thorium, and has been used in the past to prepare feed-specific SOPs for alternate feed materials
such as Sequoyah Fuels and Heritage. The Mill will prepare an Ore-specific SOP, in the same
manner as specific SOPs have been adopted for handling feed materials with elevated levels of
thorium in the past. The radiation protection procedures in the Ore-specific SOP are expected to
be similar to those in the Sequoyah Fuels-specific SOP, because the natural thorium content of the
Ore is similar to the natural thorium content of the Sequoyah Fuels material.
As discussed above and in EFRI's letter of June 25, 2020, the Ore will be shipped to the Mill in
Supersacks in IMCs or other LSA-1 approved containers. Trucks arriving at the Mill site will be
received according to existing Mill procedures. The Supersacks will be unloaded from the trucks
onto the ore pad for temporary storage until the material is scheduled for processing. The Ore will
remain within the Supersacks while stored on the ore pad. Maintaining the Ore in the Supersacks
pending processing will prevent any windblown dust from emanating from the Ore. Further, the
Ore is dry (expected to have 0.5-1.0% moisture content), and by maintaining the Ore in the
Supersacks pending processing any water infiltration will be prevented, all of which means that
there will be no chance of any moisture seepage out of the Supersacks while on the Ore pad.
Because the Ore does not significantly differ in radiological activity from other ores and alternate
feed materials, and because the Ore will be stored in Supersacks on the Mill's ore pad pending
processing, there will be no environmental impacts associated with the Ore or similar natural
Letter to Ty L. Howard
September 9, 2020
Page 33 of 41
rnonazite sand ores over and above those associated with other ores and alternate feed materials
handled at the Mill on a routine basis.
Occupational Thcpostire — Analysis of any N6n-RadiOlogiCa1 Effects. As discussed above, the
REEs and heavy metals in the Ore are already present in uranium ores historically and currently
processed at the Mill.
Experience at Chemours' Offerman separation plant has determined that the Ore is stable under
ambient environmental conditions and does not require any special handling. The only potential
operational exposure to dust would be associated with unloading the Supersacks into the grizzly,
if that process sequence were to be selected. Dust protection measures already in place for
processing of other ores and alternate feed materials will be sufficient for the management of dust
hazards from REEs during introduction into the grizzly. If the Ore is introduced into the Mill
process by a means other than the grizzly, such as directly into the leach tanks, suitable dust
suppression measures as well as worker PPE equipment will be utilized as required to meet all
radiological and occupational protection requirements. For the production of a dewatered REE
Concentrate, as currently planned, all subsequent steps in the Mill will be wet processes with no
dust generation and no pathway for worker exposure over and above norrnal Mill operations.
Should the Mill produce a dried REE Concentrate in the future, the level of worker respiratory
protection needed for conventional or vacuum dryer operations and packaging, is already in place
at the Mill for vanadium and yellowcake drying and packaging.
The following additional reagents are expected to be used in the REE recovery process:
• HC1 solution;
* Barium chloride; and
• Barium sulfate.
Although HC1 is currently not added to the Mill circuits, it is already circulating in the Mill. The
introduction of alternate feed materials with high chloride content into the acid leach system
generates HC1 upon contact with sulfuric acid. For example, Molycorp alternate feed material had
up to 89,900 mg/kg (9%) chloride, and several alternate feed materials that continue to be received
and processed have comparable levels of chloride. Since its inception, the Mill has also stored and
used high strength HCI in the lab. The Mill also adds chloride ion in the form of sodium chlorate,
and sodium chloride in other parts of the Mill. Appreciable quantities of sodium chloride are added
to the uranium SX for processing specific (acidic) solutions. An indication of the level of HCI in
circulation is the approximately 40 g/L of chloride measured in the Cell 1 evaporation cell at acidic
pH levels, as a result of this SX process.
Hence, the Mill has introduced chloride and managed HCI in the Mill circuits, Lab and TMS on a
routine basis. Existing SOPs and worker protection measures for the aggressive reagents such as
sulfuric acid used by the Mill on a regular basis are more than sufficient for worker protection
frorn HCI in solutions.
Letter to Ty L. Floward
September 9, 2020
Page 34 of 41
Barium will be chemically the same as magnesium, calcium, and other alkaline earths already
introduced into the Mill with other ores and alternate feed materials. These are currently present
in large proportion in the Mill and TMS as discussed in Tables 4 and 6.
Due to the use of sulfuric acid leaching, both the acid leach circuit and the TMS are essentially
acid sulfate systems with sulfate levels orders of magnitude greater than will be added with barium
sulfate reagent.
In sumrnary, each of the REE process reagents:
• is already used and stored at the Mill;
• has already been circulated within the Mill after being with other ores or alternate feed
materials; or
• is generated and managed in the Mill as part of normal uranium recovery chemistry in the
Mill.
As a result, for each of the reagents:
* the Mill already has appropriate worker safety protection in place; and
* the chemical is already present in the tailings.
Public Exposure — Analysis of any Radiological and Non-Radiological Effects. As discussed
above and in EFRI' s letter of June 25, 2020, the Ore will be shipped to the Mill in Supersacks in
IMCs or other LSA- 1 approved containers. The Ore will remain within the Supersacks while
stored on the ore pad. The Supersacks will be inspected and cover or other measures will be
applied if deterioration of the fabric or seams is detected. If the Ore is introduced into the Mill
process by a means other than the grizzly, such as directly into the leach tanks, suitable dust
suppression measures as well as worker PPE equipment will be utilized as required to meet all
radiological protection requirements. Once the Ore is fed into the Mill process, there will be no
other pathway for public exposure from the REEs. If an existing vanadium dryer, scrubber,
packaging system and baghouse are used to produce dried REE Concentrate in the future,
emissions would be controlled in the same fashion as ernissions from vanadium production. If
vacuum dryers were to be used, they would have no emission stack and could not generate off-site
emissions. The natural thorium will be removed to tailings prior to precipitation of the uranium.
The recovered uranium will be precipitated, dried and packaged in accordance with existing Mill
SOPs, which address exposures to the public from uranium and its daughters.
As a result, because of the absence of pathways to public exposure to the Ore or similar natural
monazite sand ores during receipt, storage, introduction into the Mill process, processing, drying,
packaging and tailings disposal, there will be no additional short term or long-term effects to the
public from non-radiological constituents in the Ore or similar natural monazite sand ores, or its
processing and tailings management over and above existing licensed operations at the Mill.
Further, since no significant physical changes to the Mill circuit and no new types of process
chemicals that are inconsistent with existing Mill operations will be necessary to process the Ore
or similar natural monazite sand ores, no significant construction impacts beyond those previously
assessed will be involved.
Letter to Ty L. Howard
September 9, 2020
Page 35 of 41
Short and long-term effects of processing uranium ore with rare earth minerals.
The .discusSion above addresses both short- and long-term effects of processing uranium ore with
REEs in the context Of occupational. and public exposures from radiological and non-radiological
factors. The following discusSion focuses on the short-term and long-term effects on the TMS and
closure and reclamation.
•Short-term and Low-term 81Tects on Tailings Management System. Processing the Ore or similar
natural monazite sand ores will have no effects beyond those identified in the approved FES, EAs,
Safety Evaluation Reports, Technical Evaluation Reports and Reclamation Plans on tailings
• operational management and closure. The Ore or similar natural monazite sand ores will have no
effect on existing approved plans for decommissioning of the Mi1L buildings, land or structures,
or reclamation of the site. The Ore or similar natural monazite sand ores will have no effect on
tailings design components addressing permanent isolation of tailings, slope stability, settlement
or liquefaction of reclaimed tailings, or design features addressing disposal cell covers or erosion
ptotedtion.
As discussed above, Table 4 summarizes the anticipated cornposition of the• tailings solution after
processing Ore or similar natural monazite sand ores. The most appreciable change in
concentration from processing Ore or similar natural monazite sand Dres•will result from barium
and zirconium. Although to a much lesser degree, noticeable changes in lead, gallium, hafnium,
natural thorium and certain REEs are also expected.
In all cases, our conclusion is that polymeric materials such as PVC and HDPE are selected for
geomembrane liners specifically because they are resistant to solutions of metals and metal salts,
like barium, zirconium, lead, gallium, hafniurn, natural thorium, and REEs in all proportions
(USEPA 1988), and, as a result, the introduction of those constituents into the TMS •ftorn
processing Ore or similar natural monazite sand ores or in any quantity or proportion is not a
concern.
Mill Tailings Closure and Reclamation. Because radionuclide content is within the ranges
associated with other ores and alternate feed materials approved for processing at the Mill, there
will be no effect on radon attenuation, gamma attenuation or TMS cover design.
Elevated concentrations of Th-nat in the tailings will not impaet tailings cover design. Radon-222
from the uranium chain and radon-220 (thoron) from the natural thorium chain are the gaseous
radioactive products of the decay of the radium isotopes radium-22 froin the uranium chain and
radium-224 from the natural thorium chain, for radon-222 and radon-220, respectively. The
UNSCEAR 2000 Report (Annex B) notes that, the radioactive half-lives of radõn and thoron and
their respective decay products are very important in determining their behaviour in the
environment. Since tnoron has a much shorter half-life (t1/2 = 55 sec) than radon (t1/2 = 3.82 days),
the distance thoron can travel before undergoing radioactive decay is very much shorter than the
distance radon can travel in the same medium. This is important with respect to consideration of
effectiveness of tailings covers.
Letter to Ty L. Howard
September 9, 2020
Page 36 of 41
To illustrate, consider that thoron (Rn-220) has a much shorter half-live (of 55.6 s) and hence the
distance that thoron can diffuse before decaying to a solid isotope is very much smaller than for
Radon (Rn-222). To illustrate, the diffusion length (see UNSCEAR 2000) is given by:
D L = AP
where
D is the bulk diffusion coefficient (m2/s)
A, is the decay constant (s-1)
• kith = 2.1 x 10-6 s-1
• krn = 1.25 x 10-2 s-1
P is the porosity.
The ratio of the diffusion lengths of thoron to radon can be estimated as

LTh _
LRn
ARn
ATh
2.1 x 10-6 _ 1
1.25 x 10-2 - 77
Thus, a cover effective for radon-222 will be nearly 80 times more effective at reducing thoron.
As the concentration of Th-nat in Cell 4A after processing 150,000 tons of Ore or similar natural
monazite sand ores from Table 4 is 5,243.3/2,150,000, the activity of Th-232 and each of its
daughters, including thoron, will be 268 pCi/g. By contrast, Cell 4A, if completely filled with
Colorado Plateau uranium ores would contain approximately 875 pCi/g Th-230 (see Abdelouas
2006) and hence 875 pCi/g Ra-226 and 875 pCi/g Rn-222 in equilibrium. The additional thoron
from the Ore and similar natural monazite sands would only add about the equivalent of 268/77 =
3.5 pCi/g to the already existing Rn-222 activity in the tailings cell of 875 pCi/g, which would be
insignificant to the cell cover design. Also, since the uranium content of the Ore is comparable to
Colorado Plateau ores, the Th-230 content of the Ore is comparable to Colorado Plateau ores and
would not add an additional source term for Ra-226 to the tailings, as the Th-230 decays into Ra-
226 over time, over and above tailings from Colorado Plateau ores.
The natural thorium chain emits gamma, similar to the gamma emitted from the Ra-226 in the
uranium chain. Gamma rays from uranium and thorium decay chains are attenuated in the same
fashion by cover materials such as used on tailings impoundments. For practical purposes, gamma
rays are reduced by a factor of about 2 for each 10 cm of cover material. The gamma rays from
the Th-232 decay chain are attenuated similarly to the gamma rays from Ra-226 (i.e., the gamma
rays from the U-238 decay chain). Thus, a cover appropriate for shielding Ra-226 gammas is also
appropriate for shielding gammas from the Th-232 decay chain. The radon barrier on a closed out
tailings area would attenuate gamma rays from either Ra-226 or the Th-232 decay chain.
Letter to Ty L. Howard
September 9, 2020
Page 37 of 41
For estimating the attenuation provided by packed earth covers over an extended radioactive
source, such as a tailings pile, the EPA (US EPA1982) uses the following equation and a half-
value layer (HVL) of 0.04 in (= 4 cm): for every 4 ctn of cover, the gamma radiation is attenuated
by a factor of 2.
Calculations can be done with Microshie1dTM. If we assume a soil cover with densities of 1.6
g/cm3 and 2.0 g/cm3, the gamma transmission factors for various thicknesses of soil cover (above
a planar Ra-226 source) are shown in the following table.
Gamma Transmission Through Soil Covers
Soil Cover
(cm)
Cover Transmission Factors
p = 1.6 g/cm3 p = 2.0 g/cm3
0 1 1
5 5.1E-01 4.4E-01
10 2.9E-01 2.3E-01
20 1.1E-01 6.7E-02
50 7.8E-03 2.9E-03
100 1.7E-04 2.7E-05
The soil cover of the current reclamation plan ET cover design for Cell 4A is 9.5 feet (289.56 cm)
thick, so gamma is effectively attenuated to zero by the cover design.
When 150,000 tons of Ore and similar natural monazite sand ores are added to Cell 4A, the
thorium-232 content will be 2,439 ppm (Table 4) or about 0.24% Th-nat, which equates to about
270 pCi/g Th-232, compared to the Ra-226 content of about 875 pCi/g, assuming Cell 4A is
comprised primarily of Colorado Plateau ores and about 1,680 pCi/g assuming Cell 4A is
comprised primarily of Arizona Strip Ores. Doubling the amount of Ore or similar monazite sand
ores in Cell 4A would increase the concentration of Th-nat to 0.48% and would result in an average
activity from Th-232 of approximately 540 pCi/g, which when added to the 875 pCi/g assumed
for Cell 4A in Table 4, would be less than the activity from a tailings Cell comprised primarily of
tailings from Arizona Strip ores which is possible under the Mill's current license. Even with this
doubled amount of Th-nat in Cell 4A, the added gamma from the Th-nat would be insignificant
relative to the gamma fields associated with normal uranium ores, and in any event, the thickness
of the cover would reduce all of these gamma emissions effectively to zero. As a result, the
addition of Ores and similar natural monazite sand ores to the Mill's TMS will not impact cover
design
Because processing the Ore or similar natural monazite sand ores and disposing of the tailings in
the TMS will not affect cover design at closure and reclamation, there will be no effect on the final
radon barrier design or its method of emplacement. Processing Ore and similar natural monazite
sand ores will have no effect on completion of the final radon barrier or on the timetable for
completion of reclamation.
Letter to Ty L. Howard
September 9, 2020
Page 38 of 41
BecauSe processing Ore and similar natural monazite sand ores will have no effect on reclamation
and closure design, construction or timing, it will have no effect on existing and approved financial
surety estimates or arrangernents. and will not require any changes to. costs of long-term
surveillance.
No Adjustments Needed to the Radiation Safety Program
As discussed above under "Occupational Exposure — Analysis of any Radiation Effects", the
uranium concentration in the Ore is comparable to a typical Colorado Plateau uraniuni or
uranium/vanadium ore, and significantly less than a typical Arizona Strip ore. As a result,
occupational exposures from uranium and its daughters will not be any different from occupational
exposures from Colorado Plateau ores, and will easily be addressed within the Mill's northal
radiation protection SOPs.
The Ore contains concentrations of natural thorium that are elevated compared to conventional
ores but comparable to the concentrations in alternate feed materials, such as Sequoyah Fuels that
have been processed at the Mill. ln accordance with the Mill's existing radiation protection
program, and as typical for any new types of Ms or alternate feed materials, the Mill will prepare
an Ore-specific SOP. The Ore-specific SOP will be developed in the same manner as specific
SOPs have been adopted for handling feed rnaterials at the Mill with elevated thorium levels in the
past, and will include application of the relevant provisions of the Mill's High Thorium Content
Ore Management SOP. The radiation protection procedures in the Ore-specific SOP are expected
to be similar to those in the Sequoyah Fuels-specific SOP, because the natural thorium content of
the Ore is similar to the natural thorium content of the Sequoyah Fuels material. The Ore-specific
SOP will be reviewed and approved by the Mill's SERP, and Mill personnel will be trained in the
approved SOP prior to procesSing the Ore or any similar natural monazite sand ore.
All of this will be accomplished pursuant to the Mill's existing radiation program. As a result, no
adjustments will be needed to the radiation protection program to process the Ore or similar natural
monazite sand ores.
No Adjustments Needed to the Environnzental Monitoring Program
The Ore has a uranium content and radioactivity levels comparable to Colorado Plateau ores, and
previously-approved alternate feed materials, and contains no additional constituents beyond those
associated with other ores or alternate feed materials previously processed at the Mill. The Mill
monitors for various isotopes in the U-nat chain under all of its monitoring programs. Also,
because Th-nat is found in ores and alternate feed materials processed at the Mill on a routine
basis, the Mill currently monitors for Th-232 in its environmental I3HV air particulate rnonitoring
stations, and in its environmental soil and vegetation sampling programs. Therefore, Ore and
similar natural monazite sand ores will pose no additional hazards during storage, processing or
disposal of tailings over and above other ores and alternate feed materials processed on a routine
basis at the Mill. As a result, no adjustments will be needed to the environmental monitoring
prograrn to process the Ore or similar natural monazite sand ores.
Letter to Ty L. Howard
September 9, 2020
Page 39 of 41
No Adjustments Needed to the Spill and Emergency Response
As discussed above, although the Mill will use some new processing chemicals, all components
of those chemicals are already present in the Mill and/or TMS, and the Mill's worker safety and
environmental monitoring program addresses those reagents or others of comparable or greater
hazard already in use at the Mill. Existing emergency response and spill response procedures are
therefore sufficient for management of potential accidents or spills of the Ore or other natural
monazite sand ores on the Mill site. As a result, no adjustments will be needed to the spill and
emergency response programs to process the Ore or similar natural monazite sand ores.
No Adjustments Needed to the Groundwater Monitoring Program
As discussed in detail under the response to RAI 2, above, Table 4 summarizes the anticipated
composition of the tailings solution after processing Ore. The most appreciable change in
concentration from processing Ore or similar natural monazite sand ores will result from barium
and zirconium. Although to a much lesser degree, noticeable changes in lead, gallium, hafnium,
natural thorium and certain REEs are also expected.
In all cases, our conclusion is that lead is already a monitored constituent under the GWDP, and
each of the other constituents is well-represented by other constituents which are already analyzed
under the GWDP. As a result, there is no need to add any of these constituents as monitoring
constituents under the GWDP because of Ore or sinailar natural monazite sand ore processing.
As a result, no adjustments will be needed to the groundwater monitoring program to process the
Ore or similar natural monazite sand ores.
References
Heileson, W. Maholon Liner/Leachate Compatibility Study Idaho National Environmental
Engineering Laboratory Design File INEEL EDF-ER-278 1/30/2003
MicroShield (Grove 2005).
United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). 2000.
Sources and Effects of Ionizing Radiation — Volume 1: Sources. Report to the General Assembly,
with Scientific Annexes, United Nations, New York.
US EPA, 1988. Risk Reduction Engineering Laboratory. Lining of Waste Containment and Other
Impoundment Facilities EPA/600/2-88/052 September 1988
U.S. EPA, 1982. Final environmental impact statement for remedial action standards for inactive
uranium processing sites (40 CFR 192) — Volume 1. EPA 520/4/82/013-1, October 1982.
Letter to Ty L. Howard
September 9, 2020
Page 40 of 41
CONCLUDING COMMENTS
The Ore is a natural uraMum ore that is similar in radionuclide and chemical content to other ores
and alternate feed materials that are processed on a routine basis at the Mill. The Ore can be
processed at the Mill for the recovery of uranium and REE Concentrate under existing processes
and standard operating procedures with minor routine modifications and adjustments typical of the
types of modifications and adjustments made by the Mill in its normal processing activities
associated with the various ores and feeds it processes on a regular basis.
Because all the constituents in the Ore have either been reported to be, or can be assumed to be,
already present in the Mill's TMS or were reported in other conventional ores or licensed •alternate
feed materials, or in reagents already in use at the Mill, at levels generally comparable to or higher
than those reported in the Ore, the resulting tailings will not be significantly different from existing
tailings at the facility, and the impacts will not be significantly different from the Ore or similar
natural monazite sand ores than from other conventional ores and previously licensed alternate
feed materials. Consequently, there will be no incremental public health, safety or environmental
impacts over and above existing licensed activities.
Further, the foregoing analysis demonstrates that, were the Mill to receive and process for uranium
and an REE Concentrate additional natural monazite sand ores from other sites in the future, with
similar characteristics to the Ore, the receipt, processing and disposal of the tailings from 15,000
tons of Ore and such other mOnaiite sands on an ongoing basis would fall well within the
environmental envelop for the Mill and would not result in any incremental public health, safety
Or environmental impacts over and above previously licensed activities. In fact, as demonstrated
in this letter, quantities of Ore or siznilar natural monazite sand ores double that amount (i.e.,
30,000 tons per year on an ongoing basis) could be handled easily and safely at the Mill with no
incremental public health, safety or environmental impacts over and above previously licensed
activities.
As a result, although not expressly evaluated in previous analyses, the process of extracting an
REE Concentrate has been environmentally evaluated for the Mill, through the evaluation of
similar activities.
The Ore and similar natural monazite sand ores are natural ores. The Mill receives natural ores
from conventional mines under its existing SOPs and License and GWDP conditions on a routine
basis. There is no reason to treat the Ore and similar natural monazite sand ores any differently.
We have dernonstrated above that existing Mill SOPs, and License and GWDP conditions are
adequate and appropriate for the Ore and similar natural monazite sand ores and that there will be
no incremental public health, safety or environmental impacts from receiving and processing Ore
and similar natural monazite sand ores over and above existing licensed activities. Consequently,
we ask for DWMRC's confirmation with our analysis that the Ore and any similar natural monazite
sand ores can be received and processed at the Mill for the recovery of uranium and REE
Concentrate under the Mill's existing License and GWDP in any quantities, but at least
approximately 5,000 tons per year of Ore and up to 25,000 tons per year of additional similar
Letter to Ty L. Howard
September 9, 2020
Page 41 of 41
natural monazite sand ores totaling 30,000 tons per year (or approximately 4% of the Mill's
licensed capacity of approximately 720,000 tons per year) on an ongoing basis, without the need
for any amendments or approval&
The Mill would perform a detailed documented evaluation through its SERP similar to the
e-valuation described in EFRI's June 25, 2020 letter and this letter, before receiving any monazite
sand ores other than Ore, to determine that the ores are natural mOnazite sand ores similar to the
Ores and that receipt and processing of such ores for the recovery •of uranium and an REE
Concentrate would not require any amendments to the Mill's License or GWDP or other approvals,
or pose any incremental public health, safety or environmental impacts Over and above processing
Ore or other previously licensed activities.
Please contact me if you have any questions or require any further information.
Yours very truly,
ENERGY FUELS RESOURCES (USA) 1Nc.
David C. Frydenlund
Chief Financial Officer, General Counsel and Corporate Secretary
cc: Scott Bakken
Garrin Palmer
Logan Stiumway
Terry Slade
Kathy Weinel
Doug Chambers. Arcadis
Jo Ann Mettler, Tischler Consulting Services
TABLES
Table 1
Range of Uranium Content in Chemours and Other Monazite Ores
Chemours Sample Name
Sample data from email 2019
REM1 typical grade
REMS2 typical grade
REMS3 typical grade
REMS4 from additonal mine area
REMS5 from additional mine area
REMS 6/11 "low grade' sample
Average
Minimum
Maximum
Monazite Ore from Africa
Typical
Minimum
Maximum
U308 U
(%) (%)
0.26 0.22
0.184 0.16
0.182 0.15
0.181 0.15
0.189 0.16
0.189 0.16
0.201 0.17
0.20 0.17
0.18 0.15
0.26 0.22
U3O8
(%)
0.12 0.10
032 0.10
0.24 0.20
Monazite Ore Queensland, Australia U3O8
(%)
Minimum
Maximum

0.12 0.1

0.18 0.15
Notes:
Chemours data is XRF from on site QC lab. One sample was provided to EFRI on December 25, 2019
The REMS sample data was provided on July 6, 2020.
, "REM" or "REMS": Rare Earth Mineral Sand.
All Chemours separation products resulted from feeds from Mission Mine.
Other Chemours mines are within the same geologic formation.
Africa XRF data provided to EFRI by the mine owner.
Queensland, Australia data obtained from World Nuclear Association 2019.
Table 2
Chemours Mineral Assay Data
Sample name SiO2 TiO2 A1203 Fe2O3 Mg0 Ca0 K20 P205 S03 Sr0 ZrO2 Ba0 Ni0 CuO P
Si Ti Al Fe Mg Ca K P S Sr Zr B a Ni Cu
(%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (
REM1 met 2116 3,4 0.220 0.470 0.154 -0.013 0.694 0.002 20.4 0.101 0.033 5.5 0.513 0.072 0.015 0.
REMS2 met 2117 3.8 0.240 0.540 0.157 0.010 0.670 0.008 20,1 0,082 0.036 6.4 0.489 0.062 0.013 0.
REMS3 met 2118 4.0 0.340 0.650 0,253 0.001 0.674 0.004 19.3 0.090 0.033 6.6 0.441 0.068 0.016 0.
REMS4 met 2119 3.1 0.180 0.410 0.169 -0.006 0,687 0.(X)5 20.3 0.100 0.033 5.1 0.456 0.075 0.019 0.
REMS5 met 2120 3.9 0.560 0A40 0.297 0.021 0.657 0.005 19.6 0.103 0.040 6.7 0.503 0.067 0.016 O.
REMS 6/11 met 2121 4.9 1.410 0,530 0.634 0.038 0.662 0.004 19.4 0.089 0.041 8.4 0.512 0.081 0.016 0.
December 25, 2019 sample 5.2 18.3 9.2
Mineral Average 4.0 0.492 0.507 0.277 0.009 0.674 0.005 19.6 0.094 0.036 6.9 0.486 0.071 0.016 0.
Atomic Wt Element 28.09 47.87 26.98 55.85 24.31 40.08 39.10 30.97 32.06 87.62 91.22 137.33 58.69 63.54 20
Atomic Wt Oxygen 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 1
Ratio element/mineral 0.47 0.60 0.53 0.70 0.60 0.71 0.83 0.44 0.40 0.85 0.74 0.90 0.79 0.80 0
Element Ave % 1.89 0.29 0.27 0.19 0.01 0.48 0.004 8.56 0.04 0.03 5.07 0.43 0.06 0.01 0
Element Avg mg/kg 18,899 2,947 2,681 1,940 51 4,817 38.7 85,633 377.1 304 50,721 4,350 557 126 1
NOTES:
The elemental metal to mineral mass ratio was calculated separately for each mineral,
based on the stoichiometric ratio of metal or cation atoms to oxygen atoms.
Chemours data was provided for one sample on December 25, 2019 and the remainder
on July 6, 2020.
Some minerals were not specified in the December 2019 sample.
Scandium was not identifed in July 6, 2020 samples, but was present in the December
Some data was reported as % and some as ppm (mg/kg) in the July 6, 2020 samples.
Values have been converted for calculations.
Met numbers (e.g. "21XX") are sample identification numbers, not years.
Sample name Er203
Er
(PLml)
Eu703
Eu
(PPM)
Ga20
Ga
(PP1n)
Gd203-
Gd
(Ppm)
Ho203
Ho
(PPM)
La203
La
¿Ppm)
Nd203
Nd
(PPM)
Pr6011
Pr
(pro)
Sm203
Sm
(PPM)
Table 2
Chemours Mineral Assay Data
Tb4Q7 Tm203 Yb203 Y203
Tb Tm Yb
(Ppm). (IVO LPINV (PPM)
REM1 met 2116 T,705 2,846 2 15,630 94.5 105..144 101,981 26,593 17,642 2,111 267 741 30,191
REMS2 met 2117 1,520 2,851 <DI_ 15,271 841 104,573 100,683 26,247 17,387 2.678 235 1,575 27.673
REMS3 met 2118 1,494 2,801 < L 14,568 820 99,881 95,880 25,036 16,549 2,527 222 11597 27,971
REMS4 met 2119 1,627 2.882 <DI_ 16,039 876 104,801 103,085 26,793 18,221 2,785 231 '1.599 29,627
REMS5 met 2120 1574 2,832 <1.A. 15,214 918 99.652 97,459 25,253 17,175 1,664 142 1.700 '29417
REMS 6/11 met 2121 2;000 2,672 6 I 4,945 991 92,807 91,844 23,996 16459 2,591 276 2.111. -330/5'.
December 25, 2019sample 1,300 1,400 11.900 700 10.580 92,400 26,900 16.900 1,700 1,000 2 t,200
Mineral Average 1.603 2.612 4.1 14,798 870 88,205 97619 25,831 17,190 2,522 246 -1,617 28A50
Atomic Wt Element 167.26 151.96 69.72 157.25 164.93 138.91 144.24 140.91 150..36 158.93 168.93 173.05 88.91
Atomic Wt Oxygen 16,0 16.0 16A) 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16,0 160 16.0
Ratio element/rnineral 0.87 0.86 0.90 0.87 0.87 0.85 0.86 0.83 0.86 0.85 0.88 0.88 0.79
Element Ave %
Element Avg mg/kg 1;401.6 2,256 3.7 12,839 759 75,211 83.693 21,380 14,824 2,145 215 1,420 22.403
NOTES:
The elemental metal to mineral mass ratio was calculated separately for each
mineral, based on the stoichiometric ratio of metal or cation atoms to oxygen
atoms.
Chemours data was provided for one sample on December 25, 2019 and the
remainder on July 6, 2020.
Some minerals were notspecified in the December 2019 sample.
Scandium was not identifed in Jtily 6, 2020 samples, but was present in the
Sopa data was reported as % and some as ppm (tng/kg) in the July 6, 2020
samples. Values have been converted feccalculations.
Met numbers (e„$. "21XX") are sample identificatiOn numbers; not years.
Table 3 Rare Earth Elements in Arizona Strip and Four Corners Area Uranium Ores
Component
A
Estimated
Conc.Range in
AZ/CO Ore
(m_g/kg or pprn)1
B
Estimated
midpoint
Conc. in
AZ/CO Ore
(mg/kg or
ppm)1
C
Estimated
Mass in
Tailings Cell
3 from 100%
AZ/CO Ore
(tons)2
D
Mass in
Tailings Cell 3
from 83%
AZ/CO 0re3
E
Concentration in
Mill Tailings
(Cell 4A)
(mg/kg or ppm)4
12.9-350 182 494.6 410.5 150.91
il )% . 0-70 35 95.4 79.2 29.10
i wililil t , 0-66.2 33.0 89.9 74.6 27.44
1-i.to-r th 0.8-26 13.4 36.5 30.3 11.14
c i.v. I( ;,1 , 1.8-98 50.0 136.1 113.0 41.53
;1i,, 0-29.8 15.0 40.9 33.9 12.47
I ,..;II.111:1 , !I ,,t 18-35 27 72.2 59.9 22.03
1 ,tc, itwi i i ti, 0.25-4.81 2.5 6.9 5.7 2.10
No.1.1;1111w ,N.i, 2,5-500 251 684.7 568.3 208.91
Itillilim 1 ri it. 0-87.9 44 119.8 99.4 36.54
ir;,,I,c !lilt i';• 1 f 0 0 0.0 0.0 0.00
$4n„t,trl.Ni,l, 0.5-140 70 191.4 158.9 58.41
2.5-8 5.3 14.3 11.9 4.37
.i41,11 r _,, _c 0.3-28.2 14.3 38.8 32.2 11.85
Iiilimft,i !1.., ..__ 0.11-7.98 4.0 11.0 9.1 3.36
itv:hiti,,s .'',; 0.2-39.8 20.0 54.5 45.2 16.63
I - 0-419 210 570.9 473.8 174.19
, 2,658 2,206.1 811
Notes to Table:
1. AZ/C0 Ore concentrations were taken from
Van Gosen, B.S. 2020 Geochernica/ and Xray Diffraction Analysis of Drilling Core Samples
from the Canyon Uranium Deposit - A solution C'ollapse Breccia Pipe ,
USGS Assay Data from Hack-Pigeon Mining Area Az Strip
Della Valle, R. S. & Brookins, D.G.. 1984 Samples from the Grants Mineral Belt, New Mexico', and
Trace Element Distributions in Sedimentary-Type Uranium Deposits
These values represent two ores from the AZ strip and one from the vicinity of the 4 corners Colorado Plateau.
2. Estimated mass of each REE in tailings is calculated by multiplying concentraton by
2,725,000 dry tons of tailings in Cell 3.
3. Total alternate feed materials prior to 2012 are 471,000 tons or 17% of the filled rnass of Cell 3.
Only one or two Alternate Feed Materials had appreciable levels of REEs. As a result, alternate feed rnaterial
contribution to REEs in tailings Cell 3 is small enough to be neglected in calculations.
We therefore assume that 83% of the mass of Cell 3 is comprised of AZ/C0 ores, with the average REE
concentrations in ore set out in Column B. Asssuming that the ore tailings are 83% of
the total tailings yields the REE masses in Column D and the REE concentrations in Column E.
4. Cell 4A was placed in operation in approximately 2012 and contains approximately 750,000 dry tons of tailings solids.
Consistent with Cell 3, we have assumed that 83% of the tailings solids in Cell 4A are from AZ/CO ores,
having the REE concentration set out in Column C. These concentrations were used with the mass
of 750,000 dry tons of Cell 4A tailings in the calculations in Table 4.
Table 4 Comparison of Chemours Ore to Tailings in a Full Cell 4A
Component
A
Estimated
AverageCone in
Om (mdkg or
ppm)
B.
Estimated
Mass in Ore
(tons)
C
Cox. Range in
Mill Taillnp
hefore Processing
Ore trudt. or ppm)
D
Eghnititrii Average
Cone, in Mill
Tailings nofore
Processing Ore
(mg/L or ppm)
E
Estimated M.
in Mill Tailings
before
Processing Ore
(ions)
F
Mass in Min
Tailings after
Ore Processing
(tons)
G
Cone._ in Mill
Tailing, abet
Ore Processing
(PPm)
71
Difference between Column
G & r) (Incrementa) increase
in Mill Tailings Conc. after
Ore Processing) [ppm)
1
Increase in Mill
Tailinp Cone. after
Ore Pnar.‘-ssing (94
.1
Conc. in Ores and Other
Alternate Feed
Mattrisla 006/811 or ppm)
Pas phasphate 10.633 • 12.845.0 NOimplyecilin MI tailings 610.000 "
Aluminum i All '2„6111 402.2 1,510 1.510 - 3.020 1422.2 1392 617 5.4 2,0011-160.000
Barium itho • .rasu 652.5 0,10 0.10 o 652.7 304 303.5 303.461 21-36.10.1
Calcium (Ca) 4,817 722.6 445-707 584 1168 1.890.6 879 2953 50.6 up co 2 1 r,ighl
Conner (CO 117 19.0 99.2463 ' 573 1,146' 1165.0 542 -.312 -5.4 6-295,000
Gallium (Oa) 13.7.58 1,988.7 Nov:ambled in Mill ea*, Hafnium (Hfi 1.82 I 273.2. Notanatyfed in Mill railings
trcin We) 1.940- 291.0 2280-5320 3.703 7A06 7.697.0 3380 -123.0 -33 , up to 164.000
Lead. UN 1.02' - 163.8 521-16A f 4 28 191.8 89 75.7 537.2 9-262,44m
Magnesium thig) 51' 7.7 2.2304.030 4.323 8.646 8.6517 4.025 -298.0 4.9 1.010-41400
Manganese t4In) 13.46 .13.4.9 112407 .217 434 665.9 310 92.7 42.7 172..1070
Nlekd t7C11 • 557 816 17.1-71',9 59 118 201.6 94 34,70 58.89 7-450.000
Potassium (K) 39 5.8 3r14,.2.020 1,230 4460 2A65.8 '1,147 413. i 41 17-7,740
Strontium (Sr) 304 45.6 Not analyzed in Mill tailinp 12 to
Sulfide itir In 56.6 Not Ann4aed in Mill tailings 9,646
Thonum-nat (Th-nall. ' 3-1.7.5) 4.762.5 240.4 240.4 t 480.8 5.2433 2.439 J• '2198 914 22.0011
Titanium ITO 2.947.00 442.1 NOt aiudyrsol in Mil( tailing% 38.1100
Zinc ti,-n) 612 91.6 169-406 292 384 675.8 314 224. 7.6 8.14.500
ZIrcorduni an 50,223 7,606.2 1.53 2.53 5 7.6112 3341 35345 139.1167 11,000
199,516 149.6 ' fOrrolltaoalYebtri, 1511.9 302 451A 210 59.1 39.1 31.600
iNVIliXrifilV b ' 5.744 4,3 ' Net•Adalyred: i 29,1 58 -. 62.5 29 0.0 -0.1 9.100
1419.641Ertn4V4-41661 i Ara 1.1 - Not Anainted 21.4 55 55.9 26 -1.4 -5.2 22.0o
riailliiÙ,11i5t 2,256 1.7 Nor Andyme . • 11,1 22 14.0 n 11.13 0.1 26.00
i3lisRilliblinaiblOte 12.839 9.6 • SOI 1tltitp...00: . 41.5 10 92.7 43 1.4 3.8 20.000
HiA86-41-67/311(2 759 0.6 Nin Analyvcd ) 115 15 7.5.5 12 -0.6 -4.9 rr.vo
Egtewouzie -44 75,2 51 544 , NOt Anulyzed 221) 44 100.5 47 24.7 112.r 5 6000
- ..ositsweiv4soiziiie, a 0.0 -•.),0(..Aua1y,-,,,,4 ... 7.1 4 .k1 ALI .10 No kerb analyzed
83.69. MA '011 ,52r41.. '209 41$ 460.6 724 14.6 7.0 1S1.1(10
11,213 15,9 -:.:Z901.4610$7zd - 36.5 73 69.0 41 49 13.3 39.500
S'lòrtìst(ritS.2 14.82.4 1 I./ .',...'...THiliAntikarr1 58.4 1.17 127.9 60 1. I 1.9 1200
Sra I 01101f, - ' 65 0,0 :"' Net Arrelyni.: 0.4 8.8 , 4 .0.3 -63 7.00
rfglhiliec13914.):5.A2itt 1.145 1.6 ,,.• got Arraigned . 11.9 24 25.3 72 -0.1 -0.7 15:00
trtifh1nOtTlilfiitf448 215 82 ' limntralyzod 3,4 7 6.9 3 4.1 4.7 2.4ti
Yti7.-.111ligit1fa -, 1420 .1.1 Nr.4 /5irel:W.461 . 16,6 33 343 16 -0.7 4.0 14.15)
VIdisTriiiiligraiali 22.403 16,6 .1ielitualyted • 174:2 348 365.2 170 -4.3 -23 419
Notes Table:
1 The coniamtrations n the Cherriours Orc are from 2019 and 2020 Glimmers data.
2. Estimated mass in the Ore is calculated by mulnplyingeolumn A by aa WHOM i 50,000 dry tons of Ore for non REEs and 15.000 inns for REF.s.
"nlia ascii:nes peotwaing Ore for 9 years at 15,000 toin/year and disposing], year of unprocessed receipts directly hi tailings.
3. Cell 4A Mill tailings range and asetuge concentrations were taken from Mill tailings samples ea date. as summarized in the Annual Tailings Characterization Report
except for Al, Ba, Sa and Vs. These metals were analyzed by AWAL Laboratories in additional samples collected in 2019.
4. CO 4A at eapieity would contain approximately 2,150.000 dry tons lailings: 150.000 tom from Ore and 2.000.000 tong from other ores- plus alternate feed Materials.
S. Mms of constiment in Mill tailings after pmcessing Ore is calculated by adding columns B and E.
6. The concentration in Mill railings after processing Ore is calculated by dividing imlumn F by 2,150,000, whieb is tbe final volume of cailings en
CeIt 4A of 150.000 dry tons dons in in ten rout (ime Year dismay disposed without priteessing). plus 2.000.000 tons of tailings from other (eeds.
7, Tbe increase in Mill milings concemration alia. processing Ore (ppm) shows Mc increase (decrease) its concentration of each constituent in thc
Mill's tailings, stated in ppm oldie total mass of tailings in Cell 4A. which is tadadated as the difference tanween column G and colionn
t The enereirUc is Mil tailings micentratiQn after prixessing Ore is the ratio of Colurno D to cob* H =potato ill C.:"
9. The concentration in other allenrate feeds represents WPM SOCCled concentrations for congituenisfonnd In characterization data for other ores and alternak feed
materials licensed for poetizing at the Mill. for comparison parposes.
10. Sulfate was Pot inicuded- Tailings solutions are overwhelmingty composed of reoidual mdfate from the MIU process.
I I. Sources of data for selected elements in other feeds is provided in Table 6.
12. Scandium was taken from the single value in the December 2019 data table hum Cliemount It e3 not present in the July 2020 data.
13. REEs in tailings were approximated from maximum values in Cell which received 83% ores, in alternate teed ltlailtrialS.
lt is IISNUMUd Cell 4A will weive tailinp from à comparable Pik of feeds.
14, Histerically. natural thorium was not measured car a mass concentration basis in tailings snludons, and activiry eorieenuations of Mree thorium isotopes, Th-228.,711-230 and 771-232,
have only beer. measured since 2015. Thmium-nat was WaiI11.11Cli from 0.002% Th-nat in natural ores per NRCP 1988 Report. 2.2% Wrier in SIC material.
and excluding Th from other alternate feed materials.
Names of Rare Eanb Elements (leMs) are shaded. MS:: conCennateena ire tailings were calculated in Table 3.
Talde 5 Comparison of WR Grace Alternate feed Material to Cell 3 Full Cell
Component
A
Estimated 'Ayirsage WRG
(cog/Icg or
ppm) •
B
Foitirtrated
• Mass in
WRG (tons)
t Conc. Range in
Mill Tailings before Processing
WRG
. (eng/L. mom )
D
Estimated Ammo
Cone. in Mill
Tailings before Processing wRO
(Mg/L Pt ppm)
E
Estimated Mass
in Mill Tailings
before Processing
WRI3 (Ions).
1,
Mass ilt Mal
Tailings after
Processing
WRG (tons)
G Cone. in Mill
Tailings after
ProeesSing
Alta (OMB)
Difference hetween
Crilumn G & D
(incremental ineressc in Mill
Tailings Conc. after
Prorating WRG) WO
I
increase in Mill Tailings
Conc, alrar
Processing
WRG rift)
1 Cone. in (lsder Ores
and Aliernme. Feed
Msierials
fengricg or ppm)
Thorium 232.(Tbs232i . ,i72,73R 1A364 ROS 4.05 22.6 143117 5,426 5417 . 59.86I 2201:10
numunvna Moo) , 0. to5 . 0.02.l 0.03g 0.03S OA 0..1 0.043 0.005 ll 3.9
Thorium 230 1131230/ 2.00R '726 726 821 144 13 2.300.000
!.10405 to TOM)
I. The coneentratien irs WR Coact ("WRG') alternate feed material is from 2000 AR data.
24 Eitirna(Cd IOUs. in the WR. Grace material is calculaind tiy multiplying column A by an assumed 203400 lOns orWR Grace material.. 5: Cell 3 when full contains approximately 2,522.000 dry tons tailings apart from WR Grace. material: 2.093.260 MRS frOM now:am% arid 425,740 tofu frornalternate feed materiels.
4. Mass of coastituent in Mill railings after processing WR Grace is calculated by adding cOlurcros 8 and, E. 5. The concentration in Mill tailings after processing WR Grace is calculated by dividing ColUftlft lbrZ725,0OO. wluclr is the 2422.000 tons of tailings fromorcs and other alternate txds plus 203.000 tons of tailings from WR Grace material
6. The inetease in /still tailings concentration after processing Ore (ppm) shows the increase (decrease) in concentration rarcaels toradituent in (he
stilfs ssnilings. mated in ppm of the total mass of railings in Cell 4A. which is ralculatrd as thr di Minineebetracen column G and coltunn D.
7. The increase in Mill tailings conemuarion alter proceming WR GraCe material is me ratio of Column I) to Column H expressed in
The concentration in otheralternate (aids represemssome selected COIWCT111131i0(15 for Monism isotopes found in iratimeteriraiimi data for other oics and alicrnale few
materials licensed for prOcessing at the Mill. for comparison purposes.
9- Sources of data for Monum isotopes in other feed.s is provided in Table 6
in. Concentratins in KM., after processing Wit Grace is the woighted.avtrage of (2.000 x 203.000) 4. (726 2.522.000) divided tna full capacity of Cell 3 or (203.000 4.. 2.322.(rstql
»Cite
Table 6: Eleinents Present in Other t)rviòustl Processed Feeds
Chemical Value in Tailings Table 4 for
Concentration irkOther Feeds
Supporting or Additional
Information
Sonice
' Batium 36,244. mg/kg 3.62% in Mblycorp Mt. Pass '
drummed alternatofeed
material
' McilYcorp ch*acterization
datain amendment request
Decenther 2009, . Cerium 31,600 mg/kg
.
__ FMRI Amendment Request
, March ,2005
DYsprositirn ' 9100 'Ing/kg -- Heritage RMPR Jtily 2000
Gadolinium - 20,000 mg/kg .... Heritage RMPR July 2000
Hafnium 5,720 mg/kg -- FMRI Amendment Request
March 2005•
Lanthanum 160,000 mg/kg — Heritage RMPR Itily 2000
: Lanthanides 217,200 mg/kg — ,.. Molycom letter 1995
Lead 262,410 mg/kg Molycorp additional
amendment r9uest 2000
Neodymium • 151,000 mg/kg --- Heritage RMPR icily 2000
' Niobiutn 27,300 mg/kg -- FMRI AmendmentRequest
March 2005
Phosphorus as
Phosphate 610,000 mg/kg CaMeco Calcined alternate feed, 8 •
to 20% as M-3 (2.6 to 6.5% or
26,000 to 65,000 mg/kg)
_
sps for Cameeo Calcined
Produet
..Praseodymium „.' 39,500 mg/i4 -- Heritage RMPR July 2600
Samarium 5,200 mg/kg -- Cited in USM ore application
summarytables for previoUsly
approved feeds • Scandium 4,170 mg/kg --
—
FMK! Amendment Reoest
March 2005
Strontium _ 1,120 mg/kg ... , SEC RMPR 2a1 1
Sulfide Up to 9,846 mg/kg -Sulfur io Molycotp Material is
inaulfide and sulfate &min
Molycorp amendment request
1995
Tantalum 51,000 mg/kg — SFC RMPR and Amendment
Request 2011
Thorium total 0.0058 to 0.0270% med. °al 80% 500 to 35.000 pCi/g
weighted avg. 15,000
Heritage RMPR My 2000
ThoriUm total 14,700 mg/kg FMRI Amendment Request:
March 2005
Thorium total 2.2% 22,00Q mg/kg
,
SFC Amendment Request
2011
Thorium-228 2.700 pCi/g Cameco calcined RMPRs
Thorium-228 up to 1,110
weighted avg, 699
SFC RMPR -2011
, Thorium-230 121 mg/kg . 2,300,000 pCi/g COtter Concelitiate'letter
Thorium-230 • up•to 3.9 mg/kg
Weighted avg 19 mpss up to 74,400 pCi/g
weighted avg. 55,685 pCi/g
SFC RMPR 2011 -
Thorium-232 54.545 mg/keL 6,000 pCi/g ', SEC RMPR 2011
Thorium-232 up to 4,990 pci/g Heritage RMPR July 2000
Titanium 38.800 nig/kg .-- March 2005
Yttrium 49,000 mg/kg _ Heritage RMPR filly 2000
Zirconium 51;000 mg/kg FMR1 Amendment Request
March.2005
Acronyms
FMRI: Fansteel Metals Resourets. Inc. SDS: Safety Data Sheet
RMPR: Radioactive Material Prof& Record
SFC. SiNuoyah Fuels Corporation
U$M ore: Uranium Source Material ore
FIGURES
RECOVERED No0H
NaOH
Na2SO4 — "1 •
BaCl2
SOLUIION
RARE EARTH
LEACH
RADIUM
REMOVAL
RARE
PRECI WASH -1100,
SOLIDS
U
TH
U & TH
LEACHING URANIUM SX -OP
H2SO4
SOLUTION
-II] SOLIDS
I RaSOA. TO
TAILINGS
TAILINGS
GRIND
GRIZZLEY & SAG MILL
(NOT ALWAYS REQUIRED)
HCI
RARE EARTH
FEED
9/9/2020 State of Utah Mail - Fwd: EFRI Responses to Request for Additional Information
Alyssa Stringham <[e-mail]>

Fwd: EFRI Responses to Request for Additional Information
1 message
Wed, Sep 9, 2020 at 12:15 PM Phillip Goble <[e-mail]>
To: Alyssa Stringham <[e-mail]>
Alyssa,
Please print out the attached document and give it to the front desk for scanning.
Thanks,
Phil
Div of Waste Management
and Radiation Control
SEP 9 2029
Forwarded message
From: Kathy Weinel <KWeinel©energyfuels.com>
Date: Wed, Sep 9, 2020 at 12:13 PM
Subject: EFRI Responses to Request for Additional Information
To: [e-mail] <[e-mail]>
Cc: Phillip Goble <[e-mail]>, [e-mail] <[e-mail]>, Thomas Rushing
<[e-mail]>, Scott Bakken <[e-mail]>, Garrin Palmer <[e-mail]>, Logan
Shumway <[e-mail]>, Terry Slade <[e-mail]>, Doug Chambers - SENES
([e-mail]) <[e-mail]>, Ho, Arnon ([e-mail])
<[e-mail]>, [e-mail] <[e-mail]>
Mr. Howard,
Attached please find the Energy Fuels Resources (USA) Inc. ("EFRI's") responses to the Division of Waste
Management and Radiation Control's ("DWMRC's") July 21, 2020 Request for Additional Information ("RAI") regarding
EFRI's, June 25, 2020 letter regarding receipt and processing of ores from Chemours at the Mill (the "Ore") for the
recovery of uranium and a rare earth element ("REE") concentrate ("REE Concentrate").
A hard copy has been sent for your convenience.
Please contact me if you have any questions on this transmittal.
Yours Truly,
Kathy Weinel
Energy Fuels Resources (USA) inc.
https://mail.google.com/mail/u/0?ik=66c2522f41&view=pt&search=all&permthid=thread-f%3A1677381150326629607&simpl=msg-f%3A167738115032... 1/2
9/9/2020 State of Utah Mail - Fwd: EFRI Responses to Request for Additional Information
Kathy Weinel
Quality As.surance Manager
t: 303.389.4134 I f: 303.389.4125
225 Union Blvd., Suite 600
Lakewood, CO 80228
htto.//www.energyfuels.com
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Chemours RAI Responses 09.09.20.pdf
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