DRC-2014-003781 - 0901a06880443ab4

State of Utah
GARY R. HERBERT
Governor
SPENCER J. COX
Lieu tenant Governor
Department of
Environmental Quality
Amanda Smith
Executive Director
DIVISION OF RADIATION CONTROL
Rusty Lundberg
Director
June 5,2014 DRC-2014-003781
Kathy Weinel, Quality Assurance Manager
Energy Fuels Resources (USA) Inc.
225 Union Blvd.
Suite 600
Lakewood, CO 80228
Subject: Energy Fuels Resources (USA) Inc. March 18, 2014 Source Assessment Report for
Sulfate in Monitoring Well MW-1 and Total Dissolved Solids in Monitoring Well
MW-3A: DRC Review Findings
Dear Ms. Weinel:
The Utah Division of Radiation Control ("DRC") has reviewed the Energy Fuels Resources
(USA) Inc. ("EFR") March 18, 2014 "Source Assessment Report for Sulfate in MW-01 and Total
Dissolved Solids in MW-3 A White Mesa Uranium Mill" ("SAR").
The SAR is broken up into two primary sections: 1) An analysis of potential sources of
contamination, and 2) A discussion and tables of data used for statistical evaluation and
generation of proposed modified GWCL's.
Proposed GWCL Revision for Sulfate in Monitoring Well MW-1
EFR proposes to modify the GWCL for TDS in Monitoring Well MW-1 from the current
838 mg/L to 846 mg/L based on source investigation and statistical evaluation in the SAR.
EFR Source Assessment Findings (Sulfate MW-1)
EFR notes that per the 2009 groundwater background report: 1) Chloride was showing an
increasing trend, 2) Fluoride was showing a decreasing trend, and 3) Uranium was showing a
significant decreasing trend. Per comparisons with current plots of indicator parameters EFR
makes the statement in the Report that "groundwater in MW-01 is behaving consistently with
background conditions and is not being affected by potential Mill activities."
Per DRC review of the SAR, it appears that the indicator parameter concentrations are consistent
with findings of the October, 2007 White Mesa Mill Background Report, as stated on p. 1-7,
195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144850 • Salt Lake City, UT 84114-4850
Telephone [phone] • Fax [phone] • T.D.D. [phone]
U'M'M'. deq. Utah, gu v
Printed on 100% recycled paper
State of Utah
GARY R. HERBERT
Governor
SPENCER J. COX
Lieutenant Governor
Department of
Environmental Quality
Amanda Smith
Executive Director
DIVISION OF RADIATION CONTROL
Rusty Lundberg
Director
June 5, 2014
Kathy Weinel, Quality Assurance Manager
Energy Fuels Resources (USA) Inc.
225 Union Blvd.
Suite 600
Lakewood, CO 80228
Subject: Energy Fuels Resources (USA) Inc. March 18, 2014 Source Assessment Report for
Sulfate in Monitoring Well MW-1 and Total Dissolved Solids in Monitoring Well
MW-3A: DRC Review Findings
Dear Ms. Weinel:
The Utah Division of Radiation Control ("DRC") has reviewed the Energy Fuels Resources
(USA) Inc. ("EFR") March 18, 2014 "Source Assessment Report for Sulfate in MW-01 and Total
Dissolved Solids in MW-3 A White Mesa Uranium Mill" ("SAR").
The SAR is broken up into two primary sections: 1) An analysis of potential sources of
contamination, and 2) A discussion and tables of data used for statistical evaluation and
generation of proposed modified GWCL's.
Proposed GWCL Revision for Sulfate in Monitoring Well MW-1
EFR proposes to modify the GWCL for TDS in Monitoring Well MW-1 from the current
838 mg/L to 846 mg/L based on source investigation and statistical evaluation in the SAR.
EFR Source Assessment Findings (Sulfate MW-1)
EFR notes that per the 2009 groundwater background report: 1) Chloride was showing an
increasing trend, 2) Fluoride was showing a decreasing trend, and 3) Uranium was showing a
significant decreasing trend. Per comparisons with current plots of indicator parameters EFR
makes the statement in the Report that "groundwater in MW-01 is behaving consistently with
background conditions and is not being affected by potential Mill activities."
Per DRC review of the SAR, it appears that the indicator parameter concentrations are consistent
with findings of the October, 2007 White Mesa Mill Background Report, as stated on p. 1-7,
195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144850 • Salt Lake City, UT 84114-4850
Telephone [phone] • Fax [phone] • T D D. [phone]
www. deq. utah.gov
Printed on 100% recycled paper
Kathy Weinel
Page 2
"there are significant increasing trends upgradient in MW-1, MW-18 or MW-19 in uranium,
sulfate, total dissolved solids (TDS), iron, selenium, thallium, ammonia and fluoride and far
downgradient in MW-3 in uranium and selenium, sulfate, TDS and pH (decreasing trend). This
provides very strong evidence that natural forces at the site are causing increasing trends in these
constituents (decreasing in pH) in other wells and supports the conclusion that natural forces are
also causing increasing trends in other constituents as well."
Significant trends in sulfate, TDS and iron are specifically noted on Table 7.1-1 of the background
report. Based on the consistency with previous studies and the location of monitoring well MW-
1, hydraulically upgradient from the White Mesa Mill it appears that the OOC status for sulfate at
MW-1 is likely due to background concentrations in the Burro Canyon Formation.
DRC Approval to Modify the Permit - Removal of GWCLs at MW-1
DRC notes that a previous agreement to modify the Permit (formal process including public
notification) by removing all GWCL's at monitoring well MW-1 was included in an April 25,
2013 letter to EFR from the Director. This decision was based primarily on the location of
monitoring well MW-1, hydraulically upgradient from the White Mesa Mill.
Since the proposal to remove GWCLs at MW-1 precedes the GWCL modification request for
sulfate in the March 18, 2014 SAR, and since the modifications would both need approval through
Permit modification, the GWCL modification for sulfate (proposed revised GWCL) will not be
included in the Permit. Therefore, no further action will be undertaken regarding the March 18,
2014 proposed sulfate GWCL modification.
Proposed GWCL Revision for Total Dissolved Solids ("TDS") in Monitoring Well MW-3 A
EFR proposes to modify the GWCL for TDS in Monitoring Well MW-3 A from the current
5,805 mg/L to 6,028 mg/L based on source investigation and statistical evaluation in the SAR.
EFR Source Assessment Findings (TDS MW-3 A)
1. MW-3 A Area Groundwater Velocity:
DRC notes that monitoring well MW-3A is located approximately 2,000 feet downgradient from
the White Mesa Mill Facility. Local groundwater velocities in the area south of the facility are
very low (pore velocities in the range of 0.55 ft/yr to 0.89 ft/yr) per findings of an EFR 2012
report titled, "Hydrogeology of the Perched Groundwater Zone in the Area Southwest of the
Tailings Cells, White Mesa Uranium Mill Site." Based on these estimated values for groundwater
velocity (developed through EFR hydraulic slug testing of installed area monitoring wells) it is
unlikely that monitoring well MW-3 A has been impacted by potential tailings solution seepage
from the facility embankments. Per the SAR "travel times in the perched aquifer at the Mill are
estimated to be 0.9 feet per year in the area between the Mill's tailings cells and MW-03A,
resulting in a travel time of over 2,000 years."
Kathy Weinel
Page 3
2. University of Utah Study:
Monitoring well MW-3 A was included in a University of Utah study conducted at the White Mesa
Uranium Mill during 2007 (Final Report of Study Findings Dated May, 2008). Tritium
concentrations in monitoring well MW-3A were found to be non-detect. If groundwater in
monitoring well MW-3 A had a surface infiltration source post 1950's (time period of atmospheric
injection of tritium during above-ground thermonuclear weapons testing), then tritium
concentrations would be expected in groundwater samples in monitoring well MW-3A.
In support of the time periods when atmospheric tritium was present, the University of Utah ("U
of U") Report (Hurst and Solomon 2008) Figure 18 includes a plot of atmospheric concentrations
of tritium in the southwest by year based on a 2006 study conducted by V.M. Heilweil and D.K.
Solomon.
The U of U Report additionally justifies that groundwater in site monitoring wells (other than
those impacted by recharge from the local wildlife ponds) is older than uranium tailings
embankments at the White Mesa Mill based on 834S and 8180 isotopic ratios. DRC notes that
monitoring well MW-3A was found not to have a stable (surface water) signature.
Based on our review of the U of U Report and specific data results for monitoring well MW-3 A
age dating of groundwater at the well indicates that the MW-3A groundwater predates Mill
construction and that uranium concentrations in groundwater at MW-3A does not appear to be
from tailings solution.
3. Indicator Parameter Evaluation
Per the SAR Part 3.2 "comparing the current, complete data set for TDS and indicator parameters
shows that groundwater behavior in MW-03A has not changed since the time of the Background
Reports. Additionally, concentrations of indicator parameters in MW-3 A are exhibiting
decreasing trends when plotted over time" Per DRC review of concentration plots for indicator
parameters in monitoring well MW-3 A, it appears that concentration trends are essentially flat for
indicator parameters (Cl, Fl, U, and S04).
EFR Proposed Modified GWCL (MW-3A TDS) Statistical Evaluation of Data
The following statistical methods were used by EFR to develop the proposed modified GWCLs:
Standard Deviation Calculation
Shapiro-Wilk Test for Normality
Least Squares Regression Analysis
Mann-Kendall Trend Analysis
A DRC cross-check of the Shapiro-Wilk Test for normality and standard deviation was conducted.
The DRC calculation results were essentially the same as the EFR conclusions. The EFR
proposed modified GWCL is based on the mean value of historic data plus two standard
Kathy Weinel
Page 4
deviations and appears to be in conformance with the Director approved statistical flow chart
which outlines a decision making process when calculating background GWCL's (Intera 2007).
The table below summarizes the EFR calculations and background rationale for the proposed TDS
GWCL.
Table of EFR Proposed Revised GWCL for TDS at Monitoring Well MW-3 A:
Well
Number
Parameter Location Current
GWCL
(mg/L)
EFR
Proposed
GWCL
Revision
(mg/L)
EFR
Background
Rationale
EFR
Method to
Determine
GWCL
DRC Finding
- Is Proposed
GWCL in
Conformance
with the
Statistical
Flow Chart?
MW-3 A TDS Downgradient
from White
Mesa Mill
Facility
5,805 6,028 Well Location
Downgradient
of Facility
Indicator
Parameters
Consistent with
Background
Report
Mean +
2(SD)
Yes
Mean + 2(SD)
UofU Study
Showing Old
Groundwater
GWCL Modification (MW-3A TDS) Recommended for Inclusion in the Groundwater
Discharge Permit
Based on DRC review findings of the EFR SAR, it is recommended that the modified GWCL for
TDS in monitoring well MW-3 A (TDS 6,028 mg/L) be included with the Groundwater Permit
Renewal, Permit No. UGW370004. Note that the modified GWCL will not be effective until
future issuance of a revised Groundwater Discharge Permit, and that the modification will be
subject to formal public notice and public participation requirements.
Sincerely,
Rusty Lundberg
Director
RL:TR:tr
U:\MON_WAST\Trushing\Energy Fuels\Source Assessment Reports\MW-01 Sulfate and MW-03A TDS 3-18-14\ES 3-18-14 SAR DRC Ltr.docx