DRC-2013-003362 - 0901a068803d0006

ENERGY FUELS
ll DRC-2013-003362 ill Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, CO. US, 80228
303 974 2140
www.energyfuels.com
VIA EMAIL AND OVERNIGHT DELIVERY
October 23, 2013
Mr. Bryce Bird
Director, Utah Division of Air Quality
State of Utah Department of Environmental Quality
195 North 1950 West
Salt Lake City, UT 84116 ^*aiat\o>-
Re: White Mesa Uranium Mill,
National Emissions Standards for Radon Emission from Operating Mill Tailings
Transmittal of September 2013 Monthly Radon Flux Monitoring Report for Cell 2
Dear Mr. Bird:
This letter transmits Energy Fuels Resources (USA) Inc.'s ("EFRFs") radon-222 flux monitoring report
for September 2013 (the "Monthly Report") pursuant to 40 CFR 61.254(b), for Cell 2 at the White Mesa
Uranium Mill (the "Mill"). Cell 2, which was constructed and placed into operation prior to December
15, 1989 is subject to the requirements in 40 CFR 61.252(a). As discussed in our 2012 Annual Radon
Flux Monitoring Report submitted March 29, 2013, Cell 2 was not in compliance with the emissions
limits in 40 CFR 61.252(a) of 20 pCi/(m2 -sec) for the calendar year 2012. This Monthly Report is
submitted pursuant to 40 CFR 261(b) which requires monthly reporting of monitoring data collected
beginning the month immediately following the submittal of the annual report for the year in non-
compliance.
Included with the Monthly Report is a Radon Flux Measurement Program Report, dated September
2013, prepared by Tellco Environmental (the "Tellco September 2013 Monthly Report"). The Tellco
September 2013 Monthly Report indicates that for the month of September 2013, the average radon flux
from Cell 2 of 17.0 pCi/(m2 -sec), complied with the standard in 40 CFR 61.252(a).
If you have any questions, please feel free to contact me at [phone].
Energy Fueis Resources (USA) Inc.
Jo Ann Tischler
Manager, Compliance and Licensing
Letter to B. Bird
September 23, 2013
Page 2 of2
cc: David C. Frydenlund
Phil Goble, Utah DRC
Dan Hillsten
Rusty Lundberg, Utah DRC
Jay Morris, Utah DAQ
Harold R. Roberts
David E. Turk
Kathy Weinel
Director, Air and Toxics Technical Enforcement Program, Office of Enforcement, Compliance
and Environmental Justice, U.S. Environmental Protection Agency
Attachments
ENERGY FUELS RESOURCES (USA) INC.
40 CODE OF FEDERAL REGULATIONS 61 SUBPART W
WHITE MESA MILL
SAN JUAN COUNTY, UTAH
TAILINGS CELL 2 MONTHLY COMPLIANCE REPORT FOR SEPTEMBER 2013
Submitted October 23, 2013
by
Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, Colorado 80228
[phone]
1) Name and Location of the Facility
Energy Fuels Resources (USA) Inc. ("EFRI") operates the White Mesa Mill (the "Mill"), located in
central San Juan County, Utah, approximately 6 miles (9.5 km) south of the city of Blanding. The Mill
can be reached by private road, approximately 0.5 miles west of Utah State Highway 191. Within San
Juan County, the Mill is located on fee land and mill site claims, covering approximately 5,415 acres,
encompassing all or part of Sections 21, 22, 27, 28, 29, 32, and 33 of T37S, R22E, and Sections 4, 5, 6, 8,
9, and 16 of T38S, R22E, Salt Lake Base and Meridian.
All operations authorized by the Mill's State of Utah Radioactive Materials License are conducted within
the confines of the existing site boundary. The milling facility currently occupies approximately 50 acres
and the tailings disposal cells encompass another 275 acres.
2) Monthly Report
This Report is the monthly report for the Mill's Cell 2 for September 2013, required under 40 Code of
Federal Regulations (CFR) 61.254(b ).
A summary of the events that gave rise to the requirement to file this monthly report under 40 CFR
61.254(b) is set out in Section 4 of this Report. A summary of the radon emissions from Cell 2 measured
in September 2013 is set out in Section 5 of this Report.
The monthly monitoring data for September 2013 required under 40 CFR 61.254(b) is provided in
Attachment 1 to this Report, which contains the Radon Flux Measurement Program Report, dated
September 2013, prepared by Tellco Environmental (the "Tellco September 2013 Monthly Report").
The results are summarized in Section 5 of this Report.
3) Name of the Person Responsible for Operation and Preparer of Report
Energy Fuels Resources (USA) Inc.
225 Union Boulevard, Suite 600
Lakewood, Colorado 80228
303.628.7798 (phone)
303.389.4125 (fax)
EFRI is the operator of the Mill and its tailings impoundments (Cells 2, 3, and 4A) and evaporation
impoundments (Cells 1 and 4B). The Mill is an operating conventional uranium mill, processing both
conventional ores and alternate feed materials. The "method of operations" at the Mill is phased disposal
of tailings. Compliance with the NESHAP standards at 40 CFR 61.252(a) is determined annually for
existing impoundments (i.e., Cells 2 and 3). The annual radon emissions for existing impoundments are
measured using Large Area Activated Charcoal Canisters in conformance with 40 CFR, Part 61,
Appendix B, Method 115, Restrictions to Radon Flux Measurements, (Environmental Protection Agency
["EPA"], 2008). These canisters are passive gas adsorption sampling devices used to determine the flux
rate of Radon-222 gas from the surface of the tailings material. For impoundments licensed for use after
December 15, 1989 (i.e., Cell 4A, and 4B), EFRI employs the work practice standard listed at 40 CFR
61.252(b)(l) in that all tailings impoundments constructed or licensed after that date are lined, are no
more than 40 acres in area, and no more than two impoundments are operated for tailings disposal at any
one time.
EFRI is submitting this monthly compliance report in conformance with the standards m 40 CFR
61.254(b).
2
4) Background Information --Summary of 2012 Annual Report
Facility History
Cells 2 and 3, which have surface areas of 270,624 m2 (approximately 66 acres) and 288,858 m2
(approximately 71 acres), respectively, were constructed prior to December 15, 1989 and are considered
"existing impoundments" as defined in 40 CPR 61.251. Radon flux from Cells 2 and 3 is monitored
annually, as discussed below.
Cells 4A and 4B were constructed after December 15, 1989, and are subject to the work practice
standards in 40 CPR 61.252(b)(l), which require that the maximum surface area of each cell not exceed
40 acres. For this reason, Cells 4A and 4B are not required to undergo annual radon flux monitoring.
Cell 3, which is nearly filled, and Cell 4A, receive the Mill's tailings sands. Cells 1 and 4B, receive
solutions only, and are in operation as evaporative ponds. Cell 2 is filled with tailings, is covered with an
interim soil cover, and is no longer in operation.
Dewatering of Cell 2
The Utah Division of Water Quality issued Groundwater Discharge Permit ("GWDP') UGW-370004 in
2005. Under Part I.D.3 of the current GWDP, EFRI has been required to accelerate dewatering of the
solutions in the Cell 2 slimes drain. Dewatering of Cell 2 began in 2008. In mid-2011, changes were
made in the pumping procedures for slimes drain dewatering of Cell 2 that resulted in an acceleration of
dewatering since that time. As discussed in more detail below, studies performed by EFRI indicate that
the increase in radon flux from Cell 2 has likely been caused by these dewatering activities. No other
changes appear to have occurred in condition, use, or monitoring of Cell 2 that could have resulted in an
increase in radon flux from the cell.
The average water level in the Cell 2 slimes drain standpipe for each of the years 2008 through 2012
indicate that water levels in Cell 2 have decreased approximately 3.25 feet (5600.56 to 5597.31 fmsl)
since 2008. Of this decrease in water level, approximately 1 foot occurred between 2010 and 2011,
reflecting the improved dewatering that commenced part way through 2011, and approximately 2 feet
between 2011 and 2012, reflecting improved dewatering for all of 2012.
Radon Flux Monitoring of Cell 2
Tellco performed the 2012 radon flux sampling during the second quarter of 2012 in the month of June.
On June 25, 2012, Tellco advised EFRI that the average radon flux for Cell 2 from samples taken in June
2012 was 23.1 pCil(m2 -sec) (referred to in the Tellco report as pCi/m2-s), which exceeded the Subpart W
requirement. The result of the 2012 radon-222 flux monitoring for Cell 3 was 18 pCi/(m2 -sec). Cell 3,
therefore, was in compliance with this standard for 2012.
40 CFR 61.253 provides that:
"When measurements are to be made over a one year period, EPA shall be provided with
a schedule of the measurement frequency to be used. The schedule may be submitted to
EPA prior to or after the first measurement period."
EFRI advised the Utah Division of Air Quality ("DAQ"), by notices submitted on August 3 and
September 14, 2012, that EFRI planned to collect additional samples from Cell 2 in the third and fourth
quarters of 2012. These samples were collected on September 9, October 21, and November 21, 2012,
3
respectively. As the June 2012 monitoring for Cell 3 indicated that it was in compliance with the
standard, further monitoring of Cell 3 was not performed.
The result of the 2012 radon-222 flux monitoring for Cell 2 was 25.9 pCil(m2 -sec) (averaged over four
monitoring events). The measured radon flux from Cell 2 in 2012 therefore exceeded the standard in 40
CFR 61.252(a) of 20 pCi/(m2 -sec).
The Cell 2 and Cell 3 radon flux results were reported in EFRI' s 2012 Annual Radon Flux Monitoring
Report (the "2012 Annual Report").
The provisions of 40 CFR 61.254(b) requires that:
"If the facility is not in compliance with the emission limits of paragraph 61.252 in the calendar
year covered by the report, then the facility must commence reporting to the Administrator on a
monthly basis the information listed in paragraph (a) of this section, for the preceding month.
These reports will start the month immediately following the submittal of the annual report for
the year in non-compliance and will be due 30 days following the end of each month."
This Report is the required monthly rep01t for September 2013 for Cell 2. Monthly monitoring will
continue until US EPA or DAQ determines that it is no longer required.
Evaluation of Potential Factors Affecting Radon Flux
In an attempt to identify the cause of the increase in radon flux at Cell 2, EFRI conducted a number of
evaluations including:
• Excavation of a series of 10 test pits in the Cell 2 sands to collect additional information needed
to ascertain factors affecting radon flow path and flux,
• Evaluation of radon trends relative to slimes drain dewatering,
• Development of correlation factors relating dewatering rates to radon flux, and
• Estimation of the thickness of temporary cover that would be required to achieve compliance with
the radon flux standard of 20 pCi/(m2 -sec), during the dewatering process.
These studies and results are discussed in detail in EFRI's 2012 Annual Radon Flux Report and
summarized in the remainder of this section.
Slimes drain dewatering data indicate that a lowering of the water level in Cell 2 has resulted in an
increase in the average radon flux, and that an increase in water level has resulted in a decrease in the
average radon flux. Changes in radon flux have consistently been inversely proportional to changes in
water levels in Cell 2 since 2008. For the last three years the change in radon flux has been between 3
and 5 pCi/(m2 -sec) per each foot of change in water level. It is also noteworthy that the significant
increases in radon flux from Cell 2 which occurred between 2010 and 2011 and between 2011 and 2012
coincided with the periods of improved (accelerated) dewatering of Ce112.
EFRI has evaluated these results and has concluded that the increase in radon-222 flux from Cell 2 that
has resulted in the exceedance of the 20 pCil(m2 -sec) standard in 40 CPR 61.252 (a) in 2012 is most
likely the unavoidable result of Cell2 dewatering activities mandated by the Mill's State of Utah GWDP.
This is due to the fact that saturated tailings sands attenuate radon flux more than dry tailings sands, and
4
the thickness of saturated tailings sands decrease as dewatering progresses. There appear to have been no
other changes in conditions at Cell 2 that could have caused this increase in radon flux from Cell 2.
These conclusions are supported by evaluations performed by SENES Consultants Limited ("SENES"),
who were retained by EFRI to assess the potential effects of dewatering on the radon flux from Cell 2 and
to provide calculations of the thickness of temporary cover required to achieve the radon flux standard
during the dewatering process.
SENES' evaluations were presented in a report provided as an attachment to EFRI's 2012 Annual Report.
SENES estimated a theoretical radon flux from the covered tailings at Cell 2 for various depths
(thicknesses) of dry tailings, and predicted future increases in radon flux as a function of decreases in
water levels.
In order to explore potential interim actions that could be taken to maintain radon flux within the 20
pCi/(m2-sec) standard, the SENES study also evaluated the extent to which radon emanations from the
cell can be reduced by increasing the thickness of the current interim cover on Cell 2.
5) September 2013 Results
Detailed results for September 2013 for Cell 2 are contained in the Tellco September 2013 Monthly
Report. As described in the Tellco September 2013 Monthly Report, monitoring was performed
consistent with 40 CFR 61 Subpart W Appendix B, Method 115 radon emissions reporting requirements.
The radon monitoring consisted of 100 separate monitoring points at which individual radon flux
measurements have been made by collection on carbon canisters. The individual radon flux measurements
were averaged to determine compliance with 40 CFR Part 61.252.
The average radon flux for Cell 2 in September 2013 was reported by Tellco to be 17.0 pCil(m2 -sec).
This radon flux value complies the 20 pCi/(m2 -sec) standard in 40 CFR 61.252.
6) Other Information
Status of Proposed Updated Final Cover Design
As part of developing the Mill's final reclamation plan required to achieve the radon flux standard of 20
pCi/(m2-sec), a final engineered cover design was submitted by TITAN Environmental in 1996 and
approved by the US Nuclear Regulatory Commission ("NRC"). An updated final cover design for the
Mill's tailings system, submitted in November 2011, is under review by the Utah Division of Radiation
Control ("DRC"), and is not currently approved. DRC provided a second round of interrogatories on the
proposed cover design and associated Infiltration and Contaminant Transport Model ("ICTM") in
February 2013, for which EFRI and its consultant, MWH Inc. are preparing responses.
7) Additional Information Required for Monthly Reports
a) Controls or Other Changes in Operation of the Facility
40 CFR 61.254(b)(1) requires that in addition to all the information required for an Annual Report under
40 CFR 61.254(b ), monthly reports shall also include a description of all controls or other changes in
operation of the facility that will be or are being installed to bring the facility into compliance.
Based on the evaluations described in Section 4, above, and as discussed during EFRI's March 27, 2013
meeting with DAQ and DRC staff, in addition to the monthly monitoring reported in this Monthly Report,
5
EFRI has proposed the following steps to ensure that radon emissions from Cell 2 are kept as low as
reasonably achievable and to bring the facility into compliance with the applicable standard:
Construction and Monitoring of Interim Cover Test Area, and Application of Additional Random
Fill
1. EFRI constructed 12 test areas on Cell 2 to assess the effect of the addition of one foot of
additional soil cover. EFR applied one foot of random fill moistened and compacted by a dozer
to 12 circular test areas of approximately 100 to 120 feet in diameter. The total tested area is
larger than the single 100 foot by 100 foot area proposed in previous Cell 2 monthly radon flux
monitoring reports. Installation of 12 test areas containing the additional 1 foot of compacted soil
was completed by August 2, 2013. Wetting and re-compaction of all 12 areas was completed
prior to the start of the September 21, 2013 monthly flux monitoring event documented in this
report.
n. The radon flux has been monitored monthly at 100 locations on Cell 2, including the 12 test
areas, since April 2013.
iii. The effectiveness of the additional compacted cover at the 12 test areas will be evaluated over the
next several months. If the desired reduction (to within compliance levels) is achieved on the test
areas, EFRI will apply additional random fill at 90% compaction, to the remainder of Cell 2, on
or before July 1, 2014. EFRI will perform the 2014 annual radon flux monitoring of Cell 2 after
placement of the fill over the entire Cell 2 area.
The proposed application of additional soil throughout Cell 2 will be conditional upon DRC confirming
that such activities will not be prejudicial to or inconsistent with the final approved cover design currently
under review, and will be credited toward the final cover design. As of the date of this report, EFRI has
not received DRC' s confirmation that the test and construction activities will not be prejudicial to or
inconsistent with the final approved cover design, or will be credited toward the final cover design.
Interim Corrective Action
EFRI has taken the following additional steps to provide interim mitigation of radon flux from Cell 2.
EFRI has identified the areas of elevated radon flux associated with known sources of radiological
contamination at or near the surface of the cell cover. Specifically:
• Windblown tailings from Cell 3 which have been deposited on Cell 2 have been removed and re-
buried in Cell 3. A berm approximately five feet high, extending the length of the Cell 3 beach
has been constructed at the edge of Cell 2, to prevent further carryover of sands from Cell 3 onto
the Cell 2 cover.
• Any contaminated material near the surface has been reburied.
• Additional cover material has been added to each of 12 identified areas of elevated flux as
described under the section entitled "Interim Cover Test Area", above.
• Monthly radon flux monitoring to assess the effectiveness of the above actions is ongoing.
b) Facility's Performance Under Terms of Judicial or Administrative Enforcement Decree
The Mill is not under a judicial or administrative enforcement decree.
6
ATTACHMENT 1
National Emissions Standards for Hazardous Air Pollutants
2013 Radon Flux Measurement Program
September 2013 Sampling Results
National Emission Standards for Hazardous Air Pollutants
2013 Radon Flux Measurement Program
White Mesa Mill
6425 South Highway 191
Blanding, Utah 84511
September 2013 Sampling Results
Cell2
Prepared for: Energy Fuels Resources (USA) Inc.
6425 S. Highway 191
P.O. Box 809
Blanding, Utah 84511
Prepared by: Tellco Environmental
P.O. Box 3987
Grand Junction, Colorado 81502
TABLE OF CONTENTS
Page
1. INTRODUCTION ...................................................................................................... ._ ............... , ... 1
2. SITE HISTORY AND DESCRIPTION .......................................................................................... 1
3. REGULATORY REQUIREMENTS FOR THE SITE .................................................................... 2
4. SAMPLING METHODOLOGY ................................... ._ ................................................................ 2
5. FIELD OPERATIONS .................................................................................................................... 3
5.1 Equipment Preparation ....................................................................................................... 3
5.2 Sample Locations, Identification, and Placement. ............................................................ 3
5.3 Sample Retrieval ............................................................................................................... 3
5.4 Environmental Conditions ................................................................................................ 4
6. SAMPLE ANALYSIS ..................................................................................................................... 4
6.1 Apparatus ........................................................................................................................... 4
6.2 Sample Inspection and Documentation ............................................................................. 4
6.3 Background and Sample Counting .................................................................................... 5
7. QUALITY CONTROL (QC) AND DATA VALIDATION ........................................................... 5
7.1 Sensitivity .......................................................................................................................... 5
7.2 Precision ............................................................................................................................. 5
7.3 Accuracy ............................................................................................................................ 6
7.4 Completeness ..................................................................................................................... 6
8. CALCULATIONS ........................................................................................................................... 6
9. RESULTS ........................................................................................................................................ 7
9.1 Mean Radon Flux ................................................................................................................ 7
9.2 Site Results ......................................................................................................................... 8
References ............................................................................................................................................ 9
Figure 1 .............................................................................................................................................. 10
Appendix A. Charcoal Canister Analyses Support Documents
Appendix B. Recount Data Analyses
Appendix C. Radon Flux Sample Laboratory Data, Including Blanks
Appendix D. Sample Locations Map (Figure 2)
i
1. INTRODUCTION
During September 21-22, 2013 Tellco Environmental, LLC (Tellco) of Grand Junction, Colorado,
provided support to Energy Fuels Resources (USA) Inc. (Energy Fuels) to conduct radon flux
measurements regarding the required National Emission Standards for Hazardous Air Pollutants
(NESHAPs) Radon Flux Measurements. These measurements are required of Energy Fuels to show
compliance with Federal Regulations (further discussed in Section 3 below). The standard is not an
average per facility, but is an average per radon source. The standard allows mill owners or operators
the option of either making a single set of measurements or making measurements over a one year
period (e.g., weekly, monthly, or quarterly intervals).
Prior to 2012, Energy Fuels had chosen to make a single set of measurements to represent the radon
flux each year; however, as the radon flux levels in Cell 2 began exceeding the regulatory standard of
20 picoCuries per square meter per second (pCi/m2-s) in 2012, Energy Fuels decided to make the
radon flux measurements on a more frequent basis. Energy Fuels is presently on a monthly radon flux
sampling plan for Cell 2. This report presents the radon flux measurements results for Cell 2 for
September 2013; the results of each monthly sampling event are presented in separate reports.
During June and July 2013, Energy Fuels placed additional cover materials at selected sample
locations of Cell 2 in an attempt to reduce the radon flux levels. The additional material was
approximately 18-24 inches thick and approximately 100 feet in diameter, centered around selected
sample location points where previous sampling had identified radon flux greater than 40 pCi/m2-s.
Tellco was contracted to provide radon canisters, equipment, and canister placement personnel as well
as lab analysis of samples. Energy Fuels personnel provided support for loading and unloading
charcoal from the canisters. This report details the procedures employed by Energy Fuels and Tellco
to obtain the results presented in Section 9.0 of this report.
2. SITE DESCRIPTION
The White Mesa Mill facility is located in San Juan County in southeastern Utah, six miles south of
Blanding, Utah. The mill began operations in 1980 for the purpose of extracting uranium and
vanadium from feed stocks. Processing effluents from the operation are deposited in four lined cells,
which vary in depth. Cell 1, Cell4A, and Cell4B did not require radon flux sampling, as explained in
Section 3 below. Cell 3 sampling results are presented in separate reports.
Cell 2, which has a total area of approximately 270,624 square meters (m2), has been filled and
covered with interim cover. The Cell 2 cover region is the same size in 2013 as it was in 2012. This
cell is comprised of one region; a soil cover of varying thickness, which requires NESHAPs radon
flux monitoring, and there are no apparent exposed tailings within Cell 2. At the time of the
September 2013 sampling, there were a few puddles of standing water in Cell 2 from storm events
earlier in the week, but the water area was not used in calculating the mean radon flux for Cell 2.
Cell 3, which has a total area of 288,858 m2, is nearly filled with tailings sand and is undergoing pre-
closure activities. This cell is comprised of two source regions that require NESHAPs radon
1
monitoring: a soil cover region of varying thickness and an exposed tailings "beaches" region. The
remaining area is covered by standing liquid in lower elevation areas. The sizes of the regions vary
due to the continuing advancement of interim cover materials and varying water levels.
3. REGULATORY REQUIREMENTS FOR THE SITE
Radon emissions from the uranium mill tailings at this site are regulated by the State of Utah's
Division of Radiation Control and administered by the Utah Division of Air Quality under generally
applicable standards set by the Environmental Protection Agency (EPA) for Operating Mills.
Applicable regulations are specified in 40 CFR Part 61, Subpart W, National Emission Standards for
Radon Emissions from Operating Mill Tailings, with technical procedures in Appendix B. At present,
there are no Subpart T uranium mill tailings at this site. These regulations are a subset of the
NESHAPs. According to subsection 61.252 Standard, (a) radon-222 emissions to ambient air from an
existing uranium mill tailings pile shall not exceed an average of 20 pCi/m2-s for each pile or region.
Subsection 61.253, Determining Compliance, states that: "Compliance with the emission standard in
this subpart shall be determined annually through the use of Method 115 of Appendix B." The
repaired Cell 4A, and newly constructed Cell 4B, were both constructed after December 15, 1989
and each was constructed with less than 40 acres surface area. Cell 4A and 4B comply with the
requirements of 40 CFR 61.252(b ), therefore no radon flux measurements are required on either
Cell 4A or 4B.
4. SAMPLING METHODOLOGY
Radon emissions were measured using Large Area Activated Charcoal Canisters (canisters) in
conformance with 40 CFR, Part 61, Appendix B, Method 115, Restrictions to Radon Flux
Measurements, (EPA, 2012). These are passive gas adsorption sampling devices used to determine
the flux rate of radon-222 gas from a surface. The canisters were constructed using a 10-inch
diameter PVC end cap containing a bed of 180 grams of activated, granular charcoal. The prepared
charcoal was placed in the canisters on a support grid on top of a Yz inch thick layer of foam and
secured with a retaining ring under I Yz inches of foam (see Figure 1, page 10).
One hundred sampling locations were distributed throughout Cell 2 (which consisted of one region) as
depicted on the Sample Locations Map (see Figure 2, Appendix D). Each charged canister was placed
directly onto the surface (open face down) and exposed to the surface for 24 hours. Radon gas
adsorbed onto the charcoal and the subsequent radioactive decay of the entrained radon resulted in
radioactive lead-214 and bismuth-214. These radon progeny isotopes emit characteristic gamma
photons that can be detected through gamma spectroscopy. The original total activity of the
adsorbed radon was calculated from these gamma ray measurements using calibration factors
derived from cross-calibration of standard sources containing known total activities of radium-226
with geometry identical to the counted samples and from the principles of radioactive decay.
After approximately 24 hours, the exposed charcoal was transferred to a sealed plastic sample
container (to prevent radon loss and/or further exposure during transport), identified and labeled, and
transported to the Tellco laboratory in Grand Junction, Colorado for analysis. Upon completion of on-
site activities, the field equipment was alpha and beta-gamma scanned for possible contamination
resulting from fieldwork activities. All field equipment was surveyed by Energy Fuels Radiation
Safety personnel and released for unrestricted use. Tellco personnel maintained custody of the
samples from collection through analysis.
2
5. FIELD OPERATIONS
5.1 Equipment Preparation
All charcoal was dried at 11 0°C before use in the field. Unused charcoal and recycled charcoal were
treated the same. 180-gram aliquots of dried charcoal were weighed and placed in sample containers.
Proper balance operation was verified daily by checking a standard weight. The balance readout
agreed with the known standard weight to within± 0.1 percent.
After acceptable balance check, empty containers were individually placed on the balance and the
scale was re-zeroed with the container on the balance. Unexposed and dried charcoal was carefully
added to the container until the readout registered 180 grams. The lid was immediately placed on the
container and sealed with plastic tape. The balance was checked for readout drift between readings.
Sealed containers with unexposed charcoal were placed individually in the shielded counting well,
with the bottom of the container centered over the detector, and the background count rate was
documented. Three five-minute background counts were conducted on ten percent of the containers,
selected at random to represent the "batch". If the background counts were too high to achieve an
acceptable lower limit of detection (LLD), the entire charcoal batch was labeled non-conforming and
recycled through the heating/drying process.
5.2 Sample Locations, Identification, and Placement
On September 21, 2013, the sampling locations were spread out throughout the Cell 2 region. The
same sampling locations that were established for the previous sampling of Cell 2 were used for this
September 2013 sampling, although the actual sample identification numbers (ID) are different. An
individual ID was assigned to each sample point, using a sequential alphanumeric system indicating
the charcoal batch and physical location within the region (e.g., 101 ... llOO). This ID was written on
an adhesive label and affixed to the top of the canister. The sample ID, date, and time of placement
were recorded on the radon flux measurements data sheets for the set of one hundred measurements.
Prior to placing a canister at each sample location, the retaining ring, screen, and foam pad of each
canister were removed to expose the charcoal support grid. A pre-measured charcoal charge was
selected from a batch, opened and distributed evenly across the support grid. The canister was then
reassembled and placed face down on the surface at each sampling location. Care was exercised not
to push the device into the soil surface. The canister rim was "sealed" to the surface using a berm of
local borrow material.
Five canisters (blanks) were similarly processed and the canisters were kept inside an airtight plastic
bag during the 24-hour testing period.
5.3 Sample Retrieval
On September 22, 2013 at the end of the 24-hour testing period, all canisters were retrieved,
disassembled and each charcoal sample was individually poured through a funnel into a container.
Identification numbers were transferred to the appropriate container, which was sealed and placed in a
3
box for transport. Retrieval date and time were recorded on the same data sheets as the sample
placement information. The blank samples were similarly processed.
All 100 charcoal samples from Cell 2 covered region were successfully containerized during the
unloading process.
Tellco personnel maintained custody of the samples from collection through lab analysis.
5.4 Environmental Conditions
A rain gauge and thermometer were placed between Cell 2 and Cell 3 to monitor rainfall and air
temperatures during sampling in order to ensure compliance with the regulatory measurement criteria.
In accordance with 40 CFR, Part 61, Appendix B, Method 115:
• Measurements were not initiated within 24 hours of rainfall.
• There was a trace (0.03 inches) of rainfall after the placement of the canisters, which had
no impact on the canister seals.
• The minimum ambient air temperature during the sampling period was 56 degrees F.
6. SAMPLE ANALYSIS
6.1 Apparatus
Apparatus used for the analysis:
• Single-or multi-channel pulse height analysis system, Ludlum Model 2200 with a
Teledyne 3" x 3" sodium iodide, thallium-activated (Nai(TI)) detector.
• Lead shielded counting well approximately 40 em deep with 5-cm thick lead walls and a 7-
cm thick base and 5 em thick top.
• National Institute of Standards and Technology (NIST) traceable aqueous solution radium-
226 absorbed onto 180 grams of activated charcoal.
• Ohaus Model C50 1 balance with 0.1-gram sensitivity.
6.2 Sample Inspection and Documentation
Once in the laboratory, the integrity of each charcoal container was verified by visual inspection of the
plastic container. Laboratory personnel checked for damaged or unsealed containers and verified that
the data sheet was complete.
All ofthe 100 sample containers and 5 blank containers received and inspected at the Tellco analytical
laboratory were verified as valid and no damaged or unsealed containers were observed.
4
6.3 Background and Sample Counting
The gamma ray counting system was checked daily, including background and radium-226 source
measurements prior to and after each counting session. Based on calibration statistics, using two
sources with known radium-226 content, background and source control limits were established for
each Ludlum/Teledyne counting system with shielded well (see Appendix A).
Gamma ray counting of exposed charcoal samples included the following steps:
• The length of count time was determined by the activity of the sample being analyzed,
according to a data quality objective of a minimum of 1,000 accrued counts for any given
sample.
• The sample container was centered on the Nal detector and the shielded well door was
closed.
• The sample was counted over a determined count length and then the mid-sample count
time, date, and gross counts were documented on the radon flux measurements data sheet
and used in the calculations.
• The above steps were repeated for each exposed charcoal sample.
• Approximately 10 percent of the containers counted were selected for recounting. These
containers were recounted on the next day following the original count.
7. QUALITY CONTROL (QC) AND DATA VALIDATION
Charcoal flux measurement QC samples included the following intra-laboratory analytical frequency
objectives:
• Blanks, 5 percent, and
• Recounts, 1 0 percent
All sample data were subjected to validation protocols that included assessments of sensitivity,
precision, accuracy, and completeness. All method-required data quality objectives (EPA, 2012) were
attained.
7.1 Sensitivity
A total of five blanks were analyzed by measuring the radon progeny activity in samples subjected to
all aspects of the measurement process, excepting exposure to the source region. These blank sample
measurements comprised approximately 5 percent of the field measurements. The results of the blank
sample radon flux rates ranged from 0.00 to 0.02 pCi/m2-s, with an average of approximately 0.01
pCi/m2-s. The lower limit of detection (LLD) was approximately 0.04 pCilm2 -s.
7.2 Precision
Ten recount measurements, distributed throughout the sample set, were performed by replicating
analyses of individual field samples (see Appendix B). These recount measurements comprised
approximately 10 percent of the total number of samples analyzed. The precision of all recount
5
measurements, expressed as relative percent difference (RPD), ranged from less than 0.1 percent to
8.0 percent with an overall average precision of approximately 1.7 percent RPD.
7.3 Accuracy
Accuracy of field measurements was assessed daily by counting two laboratory control samples with
known Ra-226 content. Accuracy of these lab control sample measurements, expressed as percent
bias, ranged from approximately -2.6 percent to +0.2 percent. The arithmetic average bias of the lab
control sample measurements was approximately -1.0 percent (see Appendix A).
7.4 Completeness
All 100 of the samples from the Cell 2 Cover Region were verified, representing 100 percent
completeness for the September 2013 radon flux sampling.
8. CALCULATIONS
Radon flux rates were calculated for charcoal collection samples using calibration factors derived
from cross-calibration to sources with known total activity with identical geometry as the charcoal
containers. A yield efficiency factor was used to calculate the total activity of the sample charcoal
containers. Individual field sample result values presented were not reduced by the results of the field
blank analyses.
In practice, radon flux rates were calculated by a database computer program. The algorithms utilized
by the data base program were as follows:
Equation 8.1:
pCi Rn-222/m2sec = [Ts* A *b*~.S(di9I7SJ]
where: N =net sample count rate, cpm under 220-662 keY peak
Ts = sample duration, seconds
b =instrument calibration factor, cpm per pCi; values used:
0.1699, forM-01/D-21 and
0.1702, for M-02/D-20
d =decay time, elapsed hours between sample mid-time and count mid-time
A =area of the canister, m2
Equation 8.2:
Gross Sample, cpm Background Sample, cpm , ____ ..;;__ _ ____:__ +
SampleCount,t,min Background Count,t,min
Error, 2CT = 2 x __!_---------~-------x Sample Concentration
Net,cpm
6
Equation 8.3:
LLD = 2.71 + (4.65){~.}
--( _s~ A *b*O:SI<Il 1S J
where: 2.71 =constant
4.65 = confidence interval factor
Sb =standard deviation of the background count rate
Ts = sample duration, seconds
b =instrument calibration factor, cpm per pCi; values used:
0.1699, forM-01/D-21 and
0.1702, for M-02/D-20
d =decay time, elapsed hours between sample mid-time and count mid-time
A =area of the canister, m2
9. RESULTS
9.1 Mean Radon Flux
Referencing 40 CFR, Part 61, Subpart W, Appendix B, Method 115 -Monitoring for Radon-222
Emissions, Subsection 2.1.7 -Calculations, "the mean radon flux for each region of the pile and for
the total pile shall be calculated and reported as follows:
(a) The individual radon flux calculations shall be made as provided in Appendix A EPA
86(1 ). The mean radon flux for each region of the pile shall be calculated by summing all
individual flux measurements for the region and dividing by the total number of flux
measurements for the region.
(b) The mean radon flux for the total uranium mill tailings pile shall be calculated as follows:
A.
Where: Is =Mean flux for the total pile (pCi/m2-s)
Ji =Mean flux measured in region i (pCi/m2-s)
Ai = Area of region i (m2)
At =Total area of the pile (m2)"
40 CFR 61, Subpart W, Appendix B, Method 115, Subsection 2.1.8, Reporting states "The results of
individual flux measurements, the approximate locations on the pile, and the mean radon flux for each
region and the mean radon flux for the total stack [pile] shall be included in the emission test report. Any
condition or unusual event that occurred during the measurements that could significantly affect the results
should be reported."
7
9.2 Site Results
Site Specific Sample Results (reference Appendix C)
(a) The mean radon flux for the Cell2 regions at the site is as follows:
Cell 2 -Cover Region = 17.0 pCi/m2-s (based on 270,624 m2 area)
Note: Reference Appendix C of this report for the entire summary of individual measurement results.
(b) Using the data presented above, the calculated mean radon flux for Cell2 is as follows:
Cell2 = 17.0 pCi/m2-s
(17.0)(270,624) = 17.0
270,624
As shown above, the arithmetic mean radon flux of the September 2013 samples for Cell 2 at
Energy Fuels White Mesa milling facility is below the NRC and EPA standard of20 pCilm2-s.
For the past several years, the site has been experiencing drought conditions, which were especially
severe during 2012 and the first half of 2013. The result of this dry weather is likely a lowering of
the moisture levels in the buried tailings and cover materials, leading to increased radon flux rates at
the site. There were a few intense storms in September 2013, which produced very heavy rain
downpours and flash flooding at Cell 2, with water running off or standing on the surface cover
material. It is not known what impact, if any, these storms had on this month's sampling of Cell 2.
Appendix C presents the summary of individual measurement results, including blank sample
analysis.
Sample locations are depicted on Figure 2, which is included in Appendix D. The map was produced
by Tellco.
8
References
U. S. Environmental Protection Agency, Radon Flux Measurements on Gardinier and Royster
Phosphogypsum Piles Near Tampa and Mulberry, Florida, EPA 520/5-85-029, NTIS #PB86-
16187 4, January 1986.
U. S. Environmental Protection Agency, Title 40, Code of Federal Regulations, July 2012.
U. S. Nuclear Regulatory Commission, Radiological Ejjluent and Environmental Monitoring at
Uranium Mills, Regulatory Guide 4.14, April 1980.
U. S. Nuclear Regulatory Commission, Title 10, Code of Federal Regulations, Part 40, Appendix A,
January 2013.
9
Appendix A
Charcoal Canister Analyses Support Documents
A
ENERGY FUELS RESOURCES (USA) INC.
WHITE MESA MILL, BLANDING, UTAH
2013 NESHAPs RADON FLUX MEASUREMENTS
CELL2
SAMPLING DATES: 9/21/13-9/22/13
SYSTEM DATE Bkg Counts (1 min. each)
1.0. #1 #2 #3
M-01/D-21 9/24/2013 146 128 150
M-01/D-21 9/24/2013 141 137 110
M-01/D-21 9/25/2013 134 133 151
M-01/D-21 9/25/2013 143 114 118
M-01/D-21 9/24/2013 146 128 150
M-01/D-21 9/24/2013 141 137 110
M-01/D-21 9/25/2013 134 133 151
M-01/D-21 9/25/2013 143 114 118
M-02/D-20 9/24/2013 120 113 125
M-02/D-20 9/24/2013 115 114 136
M-02/D-20 9/25/2013 139 121 131
M-02/D-20 9/25/2013 124 129 108
M-02/D-20 9/24/2013 120 113 125
M-02/D-20 9/24/2013 115 114 136
M-02/D-20 9/25/2013 139 121 131
M-02/D-20 9/25/2013 124 129 108
c
ACCURACY APPRAISAL TABLE
SEPTEMBER 2013 SAMPLING
Source Counts (1 min. each)
#1 #2 #3
10116 10302 10298
10276 10112 10239
10037 10080 10048
10225 10208 10192
10123 10043 10233
10072 10136 10055
10321 10061 10072
10193 10174 10169
10175 10205 10213
10070 10010 10063
10025 9994 10036
10006 10155 10001
10144 10041 10099
10126 10092 10105
9878 9905 10092
10154 10018 10020
AVG NET YIELD FOUND SOURCE
cpm cpm/pCi pCi ID
10097 0.1699 59431 GS-04
10080 0.1699 59327 GS-04
9916 0.1699 58362 GS-04
10083 0.1699 59349 GS-04
9992 0.1699 58809 GS-05
9958 0.1699 58613 GS-05
10012 0.1699 58929 GS-05
10054 0.1699 59174 GS-05
10078 0.1702 59215 GS-04
9926 0.1702 58320 GS-04
9888 0.1702 58096 GS-04
9934 0.1702 58365 GS-04
9975 0.1702 58609 GS-05
9986 0.1702 58672 GS-05
9828 0.1702 57744 GS-05
9944 0.1702 58423 GS-05
AVERAGE PERCENT BIAS FOR ALL ANALYTICAL SESSIONS:
KNOWN %BIAS I
pCi
59300 0.2%
59300 0.0%
59300 -1.6%
59300 0.1%
59300 -0.8%
59300 -1.2%
59300 -0.6%
59300 -0.2%
59300 -0.1%
59300 -1.7%
59300 -2.0%
59300 -1 .6%
59300 -1 .2%
59300 -1 .1%
59300 -2.6%
59300 -1.5%
-1 .0%
BALANCE OPERATION DAILY CHECK
BalanceModel: OhttiAS 'Por-1--o -~votWJ SN: 12307
Standard Weight (g): _2. __ 0_0_~_0----=,j.,__ ________ _
Date Pre-check (g) Post-check (g) O.K.±0.1%? By .
9/2~/1? 200.0 200,0 Y-t>5 ~~
q/"LS/'3 -:2. oo .0
(-PL~ ...... ~00,0 y-;
Appendix B
Recount Data Analyses
B
CLIENT: ENERGY FUELS RESOURCES PROJECT: RADON FLUX MEASUREMENTS, WHITE MESA MILL
PILE: 2 BATCH: I SURFACE: SOIL
AREA: COVER DEPLOYED: 9 21 13 RETRIEVED: 9
COUNTED BY: DLC FIELD TECHNICIANS: MC,CS,TE,DLC
COUNTING SYSTEM 1.0.: M01/D21, M02/D20 CAL. DUE: 6/14/14
AIR TEMP MIN: 56oF
22 13 CHARCOAL BKG:
DATA ENTRY BY: DLC
PROJECT NO.: 13004.00
WEATHER: NO RAIN
153 cpm Wt. Out:
TARE WEIGHT:
180.0
29.2
g.
g.
GRID SAMPLE RETRIV ANALYSIS MID-TIME CNT GROSS GROSS RADON ± LLD PRECISION
LOCATION I . D . HR MIN HR MIN MO DA YR HR MIN (MIN) COUNTS WT IN pCi/rn2 s pCi/m2 s pCi/m2 s % RPD
IlO
RECOUNT
I20
RECOUNT
I30
RECOUNT
I40
RECOUNT
ISO
RECOUNT
I60
RECOUNT
I70
RECOUNT
ISO
RECOUNT
I90
RECOUNT
IlOO
RECOUNT
IlO
IlO
I20
I20
I30
I30
I40
I40
ISO
ISO
I60
I60
I70
I70
ISO
ISO
I90
I90
IlOO
IlOO
s 20 8 29 9 24 13 9
8 20 s 29 9 25 13 9
s 53 8 44 9 24 13 9
s 53 s 44 9 25 13 9
43
36
54
36
8 23 8 30 9 24 13 10 1
8 23 8 30 9 25 13 9 38
7 50 s 15 9 24 13 10 11
7 50 s 15 9 25 13 9 39
9 16 9 0 9 24 13 10 23
9 16 9 0 9 25 13 9 41
8 57 8 46 9 24 13 10 31
s 57 8 46 9 25 13 9 41
9 1S s 59 9 24 13 10 38
9 18 8 59 9 25 13 9 43
9 4S 9 21 9 24 13 10 4S
9 4S 9 21 9 25 13 9 43
9 36 9 17 9 24 13 10 55
9 36 9 17 9 25 13 9 44
9 53 9 33 9 24 13 11 8
9 53 9 33 9 25 13 9 45
1
1
1
1
1
1
2
2
1
1
1
1
1
1
1
1
1
1
2
2
6064
5019
13S73
11412
10496
8834
1342
1172
21323
18670
80S9
6947
2474
2112
2492
2129
1161
1002
1512
1292
228.8
228.8
226.3
226.3
226.1
226.1
229.4
229.4
226.5
226.5
226.9
226.9
229.7
229.7
220.S
220.8
228.9
228.9
230.9
230.9
12.1
11.9
2S.3
27.8
21.2
21.2
1.1
1.1
44 .0
45 .7
16.5
16.8
4.S
4.8
4.9
4.9
2.1
2.1
1.3
1.2
1.2
1.2
2.S
2.S
2.1
2.1
0.1
0.1
4.4
4.6
1.7
1.7
0.5
0.5
0.5
0.5
0.2
0.2
0 .1
0 .1
0.04
0.05
0.04
0 .05
0 .04
0 .05
0.04
0.04
0.04
0.05
0.04
0.05
0.04
0.05
0.04
0.05
0.04
0.05
0 .04
0 .05
1. 7%
1.S%
0.0%
0.0%
3.8%
1. 8%
0.0%
0.0%
0.0%
S.O%
AVERAGE PERCENT PRECISION FOR THE CELL 2 COVER REGION: 1 .7%
Page 1 of 1
Appendix C
Radon Flux Sample Laboratory Data (including Blanks)
c
CLIENT: ENERGY FUELS RESOURCES PROJECT: RADON FLUX MEASUREMENTS, WHITE MESA MILL
PILE: 2 BATCH: I SURFACE: SOIL
AREA: COVER DEPLOYED: 9 21 13 RETRIEVED: 9
COUNTED BY: DLC FIELD TECHNICIANS: MC,CS,TE,DLC
COUNTING SYSTEM I.D.: M01/D21, M02/D20 CAL. DUE: 6/14/14
AIR TEMP MIN: 56oF
22 13 CHARCOAL BKG:
DATA ENTRY BY: DLC
PROJECT NO.: 13004.00
WEATHER: NO RAIN
153 cpm Wt. Out:
TARE WEIGHT:
180.0
29.2
GRID SAMPLE DEPLOY RETRIV ANALYSIS MID-TIME CNT GROSS GROSS RADON ± LLD
g.
g.
LOCATION I . D. HR MIN HR MIN MO DA YR HR MIN (MIN) COUNTS WT IN pCi/m2 s pCi /m2 s pCi/m2 s COMMENTS:
IOl
I02
I03
I04
I05
I06
I07
I08
I09
IlO
Ill
I12
I13
I14
I15
I16
I17
I18
I19
I20
I21
I22
I23
I24
I25
I26
I27
I28
I29
I30
I31
I32
I33
I34
I35
I36
I37
IOl
I02
I03
I04
I05
I06
!07
!08
I09
IlO
Ill
I12
I13
Il4
I15
I16
I17
I18
I19
!20
!21
I22
!23
!24
!25
!26
!27
!28
!29
I30
I31
I32
I33
I34
I35
I36
I37
7 50 8 15 9 24 13 9
7 53 8 17 9 24 13 9
7 56 8 18 9 24 13 9
8 0 8 2 0 9 24 13 9
8 3 8 21 9 24 13 9
8 6 8 23 9 24 13 9
8 10 8 24
8 13 8 26
8 16 8 27
8 20 8 29
8 23 8 30
8 26 8 32
8 29 8 33
8 32 8 35
8 36 8 36
8 39 8 38
8 42 8 3 9
8 45 8 41
8 49 8 42
8 53 8 44
8 53 8 44
8 49 8 42
8 45 8 41
8 42 8 3 9
8 39 8 38
8 36 8 36
8 32
8 29
8 26
8 23
8 20
8 16
8 13
8 10
8 6
8 3
8 0
8 35
8 33
8 32
8 30
8 29
8 27
8 26
8 24
8 23
8 21
8 20
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 9
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
36
35
38
38
40
40
41
41
43
43
45
44
47
47
49
50
52
52
54
54
55
55
57
57
58
58
0
0
1
1
3
3
4
4
6
6
7
2
1
1
1
1
1
1
1
1
1
2
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Page 1 of 3
1581
6045
2310
11608
1671
1042
1899
4009
11938
6064
1070
24031
9340
5913
2732
1407
3898
8163
12148
13873
8123
8457
7196
1668
38532
2027
27989
8285
18253
10496
10312
13134
4064
2622
7662
7384
8890
229.3
229.4
229.4
230.8
227.5
230.4
229.5
229.9
229.0
228.8
227.6
231.9
231.3
225.4
229.3
228.6
226.3
226.9
227.7
226.3
229.4
226.3
231 .3
230.7
229.5
228.3
230.6
227.7
231.4
226.1
228.9
232.2
231.5
232.4
231.9
228.2
229.6
1.3
11.9
4.4
23.2
3 .1
1.8
3 .6
7 .9
24 .1
12.1
0.8
48.8
18.8
11.8
5.3
1.1
7.7
16.5
24.8
28.3
16.5
17.1
14.5
3.1
79.1
3.9
57.2
16.7
37.2
21.2
20.8
26.5
8.0
5.0
15.3
14.7
17.8
0.1
1.2
0.4
2.3
0.3
0.2
0.4
0.8
2.4
1.2
0.1
4 .9
1.9
1.2
0.5
0.1
0.8
1.6
2.5
2.8
1.6
1.7
1.5
0.3
7.9
0.4
5 .7
1.7
3.7
2.1
2.1
2.7
0 .8
0.5
1.5
1.5
1.8
0.04
0.04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0 .04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0 .04
0 .04
0.04
40' NW
CLIENT: ENERGY FUELS RESOURCES PROJECT: RADON FLUX MEASUREMENTS, WHITE MESA MILL
PILE: 2 BATCH: I SURFACE: SOIL
AREA: COVER DEPLOYED: 9 21 13 RETRIEVED: 9
COUNTED BY: DLC FIELD TECHNICIANS: MC,CS,TE,DLC
COUNTING SYSTEM I.D.: M01/D21, M02/D20 CAL. DUE: 6/14/14
AIR TEMP MIN: 56•F
22 13 CHARCOAL BKG:
DATA ENTRY BY: DLC
PROJECT NO.: 13004.00
WEATHER: NO RAIN
153 cpm Wt. Out:
TARE WEIGHT:
180.0
29.2
GRID SAMPLE DEPLOY RETRIV ANALYSIS MID-TIME CNT GROSS GROSS RADON ± LLD
g.
g.
LOCATION I. D. HR MIN HR MIN MO DA YR HR MIN (MIN) COUNTS WT IN pCi/m2 s pCi/m2 s pCi/m2 s COMMENTS:
I3S
I39
I40
I41
I42
I43
I44
I45
I46
I47
I4S
I49
ISO
I 51
I 52
I 53
I 54
ISS
IS6
IS7
ISS
I 59
I60
I61
I62
I63
I64
I65
I66
I67
I6S
I69
I70
I71
I72
I73
I74
I3S
I39
I40
I41
I42
I43
I44
I45
I46
I47
I4S
I49
ISO
IS1
I 52
I 53
I 54
ISS
I 56
I 57
ISS
I 59
I60
I61
I62
I63
I64
I65
I66
I67
I6S
I69
I70
I71
I72
I73
I74
7 56 s 1S
7 53 8 17
7 50 8 15
9 34 9 14
9 32 9 13
9 30 9 11
9 28 9 9
9 26 9 8
9 24 9 6
9 22 9 5
9 20 9 3
9 1S 9 2
9 16 9 0
9 14 8 59
9 12 8 57
9 10 8 56
9 s s 54
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
8
10
11
14
15
18
17
20
20
22
22
23
23
25
25
26
26
9
9
9
9
6
4
2
0
8 53 9 24 13 10 28
8 51 9 24 13 10 28
8 50 9 24 13 10 29
8 48 9 24 13 10 29
8 59 8 47
8 57 8 46
8 57 8 46
8 59 8 47
9 2 8 48
9 4 8 50
9 6 8 51
9 9 8 53
9 11 8 54
9 14 8 56
9 16 8 57
9 18 8 59
9 21 9 0
9 23 9 2
9 25 9 3
9 28 9 5
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
31
31
32
32
34
34
35
35
37
37
38
38
40
40
41
41
2
1
2
1
2
3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Page 2 of 3
1090
16843
1342
1853
1245
1226
22014
81099
2155
33883
27283
3128
21323
6778
3885
1483
13240
4671
37787
18500
9632
6093
8089
2843
4892
2727
14134
14230
17896
22769
1911
3102
2474
14838
6849
5644
8103
227.1
228.3
229.4
224.2
226.7
228 .0
228.7
231.2
228.4
224.2
227.1
229.4
226.5
223.9
224.4
229.3
224.2
228.3
221.3
226.2
221.8
224.3
226.9
229.5
230.3
228.5
228.1
233.2
227.7
230.4
227.2
231.9
229.7
230.6
227.0
229.5
230.3
0 .8
34.0
1.1
3.5
1 .0
0 .5
45 .4
168 .4
4 .2
70.2
56.3
6.2
44.0
13.8
7.7
2.8
27.2
9.4
78.1
38.1
19.7
12.4
16.5
5.6
9.8
5.4
29.1
29.3
36.9
47.2
3.7
6.2
4.8
30.7
14.0
11.5
16.6
0.1
3.4
0.1
0.4
0.1
0.1
4.5
16.8
0.4
7.0
5.6
0.6
4.4
1.4
0.8
0.3
2.7
0.9
7.8
3.8
2.0
1.2
1.6
0.6
1.0
0.5
2.9
2.9
3.7
4.7
0.4
0.6
0.5
3.1
1.4
1.1
1.7
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
20 I SE
CLIENT: ENERGY FUELS RESOURCES PROJECT: RADON FLUX MEASUREMENTS, WHITE MESA MILL
PILE: 2 BATCH: I SURFACE: SOIL
AREA:COVER DEPLOYED: 9 21 13 RETRIEVED: 9
COUNTED BY: DLC FIELD TECHNICIANS: MC,CS,TE,DLC
COUNTING SYSTEM I.D.: M01/D21, M02/D20 CAL. DUE: 6/14/14
AIR TEMP MIN: 56aF
22 13 CHARCOAL BKG:
DATA ENTRY BY: DLC
PROJECT NO.: 13004.00
WEATHER: NO RAIN
153 cpm Wt. Out:
TARE WEIGHT:
180.0
29.2
GRID SAMPLE DEPLOY RETRIV ANALYSIS MID-TIME CNT GROSS GROSS RADON ± LLD
g.
g.
LOCATION I. D. HR MIN HR MIN MO DA YR HR MIN (MIN) COUNTS WT IN pCi /m2 s pCi/m2 s pCi/m2 s COMMENTS:
175
I76
!77
17S
I79
ISO
IS1
IS2
IS3
IS4
ISS
IS6
IS7
ISS
IS9
I90
I91
I92
I93
I94
I95
I96
I97
I9S
I99
!100
175
!76
177
17S
!79
ISO
IS1
IS2
IS3
IS4
ISS
IS6
I87
ISS
IS9
I90
I91
I92
I93
I94
I95
I96
I97
I9S
I99
!100
BLANK CANISTER ANALYSIS:
9 30
9 32
9 53
9 51
9 49
9 48
9 46
9 45
9 44
9 42
9 40
9 3S
9 36
9 35
9 35
9 36
9 38
9 6
9 8
9 26
9 24
9 23
9 21
9 20
9 18
9 17
9 15
9 14
9 12
9 11
9 9
9 16
9 17
9 19
9 39 9 20
9 41 9 22
9 43 9 23
9 44 9 25
9 45 9 26
9 47 9 28
9 4S 9 29
9 51 9 31
9 53 9 33
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 10
9 24 13 11
9 24 13 11
9 24 13 11
9 24 13 11
9 24 13 11
9 24 13 11
43
43
45
44
48
48
49
49
51
51
52
52
54
54
55
55
57
57
58
58
0
2
6
6
8
8
1
1
3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
5
1
1
2
2
1255
1212
1250
1487
1377
2492
5383
5442
8617
1713
2541
3297
1729
6141
12366
1161
1000
2090
6234
2441
1140
1234
8610
167S
1317
1512
226.8
229.8
225.1
221.7
230.2
220.8
226.1
224.2
232.4
229.9
227.0
225.5
225.7
228.6
230.2
228.9
230.1
227.3
229.3
227.6
228.9
227.7
230.6
217.2
226.9
230.9
AVERAGE RADON FLUX RATE FOR THE CELL 2 COVER REGION:
2.3
2.2
0.6
2.8
2.6
4.9
11.0
11.1
17.8
3.3
5.0
6.6
3.3
12.5
25.5
2 .1
1.8
4 .0
12 .7
4 .8
0 .9
0 .2
17 .7
3 .2
1.1
1.3
0.2
0.2
0.1
0.3
0.3
0.5
1.1
1.1
1.8
0.3
0.5
0.7
0.3
1.3
2.6
0.2
0 .2
0.4
1.3
0.5
0 .1
0.0
l.S
0.3
0.1
0.1
17.0 pCi/m2 s
0~2-MIN
168.4 MAX
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0 .04
0 .04
0.04
0.04
0.04
0.04
0.04
0.04
0.04
0 .04
0.04
0.04
0.04
0.04
GRID SAMPLE RETRIV ANALYSIS MID-TIME CNT GROSS GROSS RADON ± LLD
20' w
LOCATION I. D. HR MIN HR MIN MO DA YR HR MIN (MIN) COUNTS WT IN p Ci/m2 s pCi/m2 s pCi/m2 s COMMENTS:
I BLANK 1
I BLANK 2
I BLANK 3
I BLANK 4
I BLANK 5
I BLANK 1 7 20 8 10 9 24 13 8
I BLANK 2 7 20 8 10 9 24 13 S
I BLANK 3 7 20 8 10 9 24 13 8
I BLANK 4 7 2 0 8 10 9 2 4 13 8
I BLANK 5 7 2 0 8 10 9 2 4 13 8
18
18
29
29
42
10
10
10
10
10
1528
1525
1614
1554
1619
206.0
207.5
206.8
206.4
206.5
0.00
0.00
0.02
0.00
0.02
AVERAGE BLANK CANISTER ANALYSIS FOR THE CELL 2 COVER REGION: 0 .01
Page 3 of 3
0.03
0.03
0.03
0.03
0.03
pCi/m2 s
0.04
0.04
0.04
0.04
0.04
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
Appendix D
Sample Locations Map (Figure 2)
0