DRC-2014-003644 - 0901a068804405ce

Department of
Environmental Quality
Amanda Smith
Executive Director
State of Utah DIVISION OF RADIATION CONTROL
Rusty Lundberg
Director
GARY R. HERBERT
Governor
SPENCER J. COX
Lieutenant Governor DRC-2014-003644
May 29, 2014
Kathy Weinel
Quality Assurance Manager
Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, Colorado 80228
RE: DRC Inspection Module RI-01, Radiological Instrumentation, May 22, 2014; RML UT1900479
Dear Ms. Weinel,
Inspection Module RI-01 was conducted May 22, 2014, by the Division of Radiation Control (DRC) at the
White Mesa Mill. The inspection focused on the Mill's Radiological Survey Instrumentation. All items
inspected met applicable regulatory requirements.
One minor discrepancy was noted during the inspection relating to the use of check sources for
beta/gamma instruments. A recommendation to revise the Radiation Protection Manual was made to the
Mill's Radiation Safety Officer at the inspection's Closeout Meeting.
All items inspected met applicable regulatory requirements and no further action is required in regard to
this inspection.
If you have any questions regarding this inspection, please contact Kevin Carney at [phone].
Sincerely,
Rusty Lundberg, Director
RL/KJC:kc
cc: Ronnie Nieves, Mill RSO
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
INSPECTION REPORT
Inspection Module:
Inspection Location:
RADMOD RI-01 Rev 0
White Mesa Mill, Blanding Utah
RM License: UT 1900479
Inspection Items:
Inspection Dates:
Inspectors:
Radiological Instrumentation
May 22, 2014
Kevin Carney, Utah Division of Radiation Control (DRC)
Personnel Contacted: Ron Nieves and Dan Hillsten.
Governing Documents:
• Radioactive Material License UT1900479
• NRC Regulatory Guide 8.30
• NRC Regulatory Guide 8.31
• White Mesa Mill SOP-PBL-RP-3
• Utah Administrative Code R313-15
• ANSI Standard N323A
Inspection Summary
The inspection was a verification of compliance with Utah Rules, ANSI N323A, NRC Regulatory
Guides 8.30 and 8.31 and White Mesa Mill (the Mill) procedures as they pertain to Radiological
Survey Instrumentation at the Mill. The inspection consisted of a review of records, direct
observations and interviews with the Radiation Protection Staff as well as other personnel on site.
Discrepancies
One minor discrepancy was noted during the inspection and is outlined below.
Inspection Items
The inspection was divided into two main sections:
• Dose Rate Instrumentation
• Count Rate Instrumentation/Sealers
The inspection outlines are noted below according to section:
C:\Users\kcarney\Documents\l le2 RMLs\Energy Fuels Resources - White Mesa\lnspections\2014 lnspections\RI-01 - May 2014\RI-01 Inspection
Report5-28-2014.doc
1 of Page 3
Dose Rate Instrumentation
At the time of the inspection, no dose rate instrumentation was in use, so none were evaluated during
the inspection.
Count Rate Instrumentation
The inspection consisted of direct observation of field instruments in use and a review of records and
procedures relating to the Mill's Count Rate Instruments including hand held survey instruments,
personnel monitors and scalers.
The inspector observed instruments which were in service on the day of the inspection. This
consisted of a visual inspection of the instruments and verifying their physical condition, presence of
a current calibration sticker and location in the field. Serial numbers for each instrument were
recorded as well as the probe serial numbers presently attached to the instrument where applicable.
After the field inspection, a records check was performed to verify the validity of each instrument's
calibration, performance of required function checks and to verify that, where applicable, the probes
that were found in use were the probes that were evaluated with their respective instruments during
calibration.
All observed instruments met all applicable requirements, although one minor discrepancy was noted
during the inspection and is outlined below.
Findings
The White Mesa Mill's Radiation Protection Manual, Section 3.1.4.1, Step 1 states: "Turn the
instrument on and place the calibrated beta/gamma (SrY)-90 check source on the face of the
detector. " The inspection found that beta-gamma instruments are function checked using the Mill's
137Cs #2 check source which is contrary to the procedural requirement. However, the inspector's
opinion is that there is no consequence to using the 137Cs check source. The daily function check's
purpose is to verify the instrument's efficiency and its ability to accurately determine radiation levels.
Whether a Sr-Y or Cs source is used, the ability of the meter to consistently and accurately measure
the source's activity is what needs to be evaluated. What is important is that the same check source
be used daily to verify consistent readings. The inspector recommended to the Mill staff that they
amend the language in their Radiation Protection Manual to reflect using the cesium source or to
reference using "an appropriate beta-gamma source" for daily beta-gamma instrument function
checks. No violation is recommended for this discrepancy.
2 of Page 3
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Report 5-28-2014.doc
Conclusion and Recommendations
No violations are recommended for this inspection. The findings noted should be re-addressed in the
Inspection Letter for this inspection and the DRC should follow up on a subsequent inspection.
Recommendation for Next Inspection
Verification of the check source procedure requirement change should be noted.
Prepared By: Kevin Carney May 28. 2014
Reviewed By: Phillip Goble 6?v May 28.2014
3 of Page 3
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Report 5-28-20l4.doc
UTAH DIVISION OF RADIATION CONTROL
RADIATION PROTECTION INSPECTION MODULE
RADMOD-RI-01 Rev 0
RADIOLOGICAL INSTRUMENTATION
DENISON MINES - WHITE MESA URANIUM MILL
RADIOACTIVE MATERIAL LICENSE UT 1900479
Inspectors: Kevin Carney
Inspection Dates: Start: May 22.2014 End: May 22.2014
Requirements, Procedures, Policies, Standards:
o Radioactive Materials License UT 1900479
o NRC Regulatory Guide 8.30
o NRC Regulatory Guide 8.31
o White Mesa Mill SOP-PBL-RP-3
o Utah Administrative Code R313-15
o ANSI Standard N323A
Personnel Contacted
Ron Nieves Mill RSO
Dan Hillston Mill Manager
Dose Rate Instrumentation
Dose Rate Instruments Inspected:
Make Model Serial Number
No dose rate instruments were evaluated during this inspection.
Page 1 of 6
Scalers
Scalers Inspected:
Make Model Instrument S/N - Probe S/N
Ludlum 30-30 265992 - N/A
Ludlum 2200 17534-PR3174
Ludlum 29-29 146781 - 145343
Count Rate Instrumentation
Count Rate Instruments Inspected:
Make Model
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
L-177-61
L-177
L-177
L-3
L-177
L-177-61
L-177-61
L-3
Instrument
Serial Number
Probe
Serial Number
264743
264740
116481
257131
264571
189581
159172
158587
RN 16489
RN17632
PR168949
PR281518
RN19527
PR19024
RN19528
PR281509
Page 2 of 6
Calibration of Survey, Counting Instruments and Scalers
Dose Rate Instrumentation
Dose Rate Instrument Calibration Records Inspected:
Make Model Serial Number
No dose rate instruments were evaluated during this inspection.
Count Rate Instrumentation/Sealers
Count Rate Instrument/Sealer Calibration Records Inspected:
Make Model Serial Number
Ludlum L-177-61
Ludlum L-177
Ludlum L-177
Ludlum L-3
Ludlum L-177
Ludlum L-177-61
Ludlum L-177-61
Ludlum L-3
Ludlum 30-30
Ludlum 2200
Ludlum 29-29
264743
264740
116481
257131
264571
189581
159172
158587
265992
17534
146781
Page 3 of 6
1) Were all inspected instruments calibrated prior to use? (SOP-PBL-RP-3)
Yes _3 No •
Comments: All inspected instruments were in calibration and were appropriately labeled with a current
calibration sticker.
2) Were all inspected instruments appropriately function checked prior to use? (SOP-PBL-RP-3)
Yes M No •
Comments: Beta-gamma and alpha instruments are checked daily prior to use. Personnel monitor function
checks are documented on a daily log: beta-gamma and alpha material/vehicle release instruments are
documented on the release point's daily vehicle scan sheet. Scalers are efficiency checked monthly and
documented on the Area Airborne Concentration Efficiencies. Information and Data Sheet.
3) Were all inspected beta-gamma instruments function checked using a Sr/Y source?
(SOP-PBL-RP-3.1.4.1 Step 1)
Yes • No |E
Comments: Beta-Gamma instruments (Ludlum Model 3 S/N's 237483 and 266292) were function checked
using a i37Cs source.
See Additional Observations and Findings below.
4) Were any instruments found being used with a probe other than what the meter was calibrated with?
Yes • No |E
Comments: All probe/instrument combinations observed in the field matched the combinations documented on
their respective calibration certificates.
Page 4 of 6
5) Were any instruments observed being used with any physical damage such as defective cords or
light leaks?
Yes • No [__
Comments: All inspected instrumentation appeared to be in satisfactory physical condition.
6) Were all calibration records inspected, for instruments currently being used, complete and accurate?
Yes _<] No •
Comments: All inspected instruments were calibrated by Ludlum Instruments and were found to be complete
and accurate.
7) Were all inspected instrument calibrations performed using NIST traceable sources?
(ANSI N323A)
Yes _3 No •
Comments: All calibration certificates contained notation attesting to NIST traceable sources being used.
8) Were all instrument calibration records filed with previous records on the same instrument and readily
retrievable? (ANSI N323A § 4.5)
Yes [X] No •
Comments: Each inspected instrument's calibration certificates were stored in a file folder particular to that
instrument. The folder's contained all previous calibration certificates for each instrument.
Page 5 of 6
Additional Observations and Findings:
Comments: Inspection Item 3: The White Mesa Mill's Radiation Protection Manual. Section 3.1.4.1.
Step 1 states: "Turn the instrument on and place the calibrated beta/gamma (SrY)-90 check source
on the face of the detector. " The inspection found that beta-gamma instruments are function
checked using the Mill's Cs-137 #2 check source which is contrary to the procedural requirement.
However, the inspector's opinion is that there is no consequence to using the cesium-137 check
source. The daily function check's purpose is to verify the instrument's efficiency and its ability to
accurately determine radiation levels. Whether a Sr-Y or Cs source is used, the ability of the meter
to consistently and accurately measure the source's activity is what needs to be evaluated. What is
important, is that the same check source be used daily to verify consistent readings. The inspector
recommended to the Mill staff that they amend the language in their Radiation Protection Manual to
reflect using the cesium source or to reference using "an appropriate beta-gamma source" for daily
beta-gamma instrument function checks. No violation is recommended for this discrepancy.
Page 6 of 6
(_\ tart c?JC
Department of
Environmental Quality
Amanda Smith
Executive Director
State of Utah DIVISION OF RADIATION CONTROL
Rusty Lundberg
Director
GARY R. HERBERT
Governor
SPENCER J. COX
Lieutenant Governor DRC-2014-003644
May 29, 2014
Kathy Weinel
Quality Assurance Manager
Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, Colorado 80228
RE: DRC Inspection Module RI-01, Radiological Instrumentation, May 22, 2014; RML UT1900479
Dear Ms. Weinel,
Inspection Module RI-01 was conducted May 22, 2014, by the Division of Radiation Control (DRC) at the
White Mesa Mill. The inspection focused on the Mill's Radiological Survey Instrumentation. All items
inspected met applicable regulatory requirements.
One minor discrepancy was noted during the inspection relating to the use of check sources for
beta/gamma instruments. A recommendation to revise the Radiation Protection Manual was made to the
Mill's Radiation Safety Officer at the inspection's Closeout Meeting.
All items inspected met applicable regulatory requirements and no further action is required in regard to
this inspection.
If you have any questions regarding this inspection, please contact Kevin Carney at [phone].
Sincerely,
Rusty Lundberg, Director
RL/KJC:kc
cc: Ronnie Nieves, Mill RSO
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
INSPECTION REPORT
Inspection Module:
Inspection Location:
RADMOD RI-01 Rev 0
White Mesa Mill, Blanding Utah
RM License: UT1900479
Inspection Items:
Inspection Dates:
Inspectors:
Radiological Instrumentation
May 22, 2014
Kevin Carney, Utah Division of Radiation Control (DRC)
Personnel Contacted: Ron Nieves and Dan Hillsten.
Governing Documents:
• Radioactive Material License UT 1900479
• NRC Regulatory Guide 8.30
• NRC Regulatory Guide 8.31
• White Mesa Mill SOP-PBL-RP-3
• Utah Administrative Code R313-15
• ANSI Standard N323A
Inspection Summary
The inspection was a verification of compliance with Utah Rules, ANSI N323A, NRC Regulatory
Guides 8.30 and 8.31 and White Mesa Mill (the Mill) procedures as they pertain to Radiological
Survey Instrumentation at the Mill. The inspection consisted of a review of records, direct
observations and interviews with the Radiation Protection Staff as well as other personnel on site.
Discrepancies
One minor discrepancy was noted during the inspection and is outlined below.
Inspection Items
The inspection was divided into two main sections:
• Dose Rate Instrumentation
• Count Rate Instrumentation/Sealers
The inspection outlines are noted below according to section:
C:\Users\kcarney\Documents\l le2 RMLs\Energy Fuels Resources - White Mesa\lnspections\2014 lnspections\RI-01 - May 20I4\RI-01 Inspection
Report 5-28-20l4.doc
1 of Page 3
Dose Rate Instrumentation
At the time of the inspection, no dose rate instrumentation was in use, so none were evaluated during
the inspection.
Count Rate Instrumentation
The inspection consisted of direct observation of field instruments in use and a review of records and
procedures relating to the Mill's Count Rate Instruments including hand held survey instruments,
personnel monitors and scalers.
The inspector observed instruments which were in service on the day of the inspection. This
consisted of a visual inspection of the instruments and verifying their physical condition, presence of
a current calibration sticker and location in the field. Serial numbers for each instrument were
recorded as well as the probe serial numbers presently attached to the instrument where applicable.
After the field inspection, a records check was performed to verify the validity of each instrument's
calibration, performance of required function checks and to verify that, where applicable, the probes
that were found in use were the probes that were evaluated with their respective instruments during
calibration.
All observed instruments met all applicable requirements, although one minor discrepancy was noted
during the inspection and is outlined below.
Findings
The White Mesa Mill's Radiation Protection Manual, Section 3.1.4.1, Step 1 states: "Turn the
instrument on and place the calibrated beta/gamma (SrY)-90 check source on the face of the
detector. " The inspection found that beta-gamma instruments are function checked using the Mill's
l37Cs #2 check source which is contrary to the procedural requirement. However, the inspector's
opinion is that there is no consequence to using the 1 7Cs check source. The daily function check's
purpose is to verify the instrument's efficiency and its ability to accurately determine radiation levels.
Whether a Sr-Y or Cs source is used, the ability of the meter to consistently and accurately measure
the source's activity is what needs to be evaluated. What is important is that the same check source
be used daily to verify consistent readings. The inspector recommended to the Mill staff that they
amend the language in their Radiation Protection Manual to reflect using the cesium source or to
reference using "an appropriate beta-gamma source" for daily beta-gamma instrument function
checks. No violation is recommended for this discrepancy.
2 of Page 3
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Report 5-28-20l4.doc
Conclusion and Recommendations
No violations are recommended for this inspection. The findings noted should be re-addressed in the
Inspection Letter for this inspection and the DRC should follow up on a subsequent inspection.
Recommendation for Next Inspection
Verification of the check source procedure requirement change should be noted.
Prepared By: Kevin Carney c^^^sa. May 28. 2014
Reviewed By: Phillip Goble ^ May 28.2014
3 of Page 3
C:\Users\kcarney\Documents\l le2 RMLs\Energy Fuels Resources - White Mesa\Inspections\2014 Inspections\RI-OI - May 20I4\RI-0I Inspection
Report 5-28-20l4.doc
UTAH DIVISION OF RADIATION CONTROL
RADIATION PROTECTION INSPECTION MODULE
RADMOD-RI-01 Rev 0
RADIOLOGICAL INSTRUMENTATION
DENISON MINES - WHITE MESA URANIUM MILL
RADIOACTIVE MATERIAL LICENSE UT 1900479
Inspectors: Kevin Carney
Inspection Dates: Start: May 22.2014 End: May 22.2014
Requirements, Procedures, Policies, Standards:
o Radioactive Materials License UT 1900479
o NRC Regulatory Guide 8.30
o NRC Regulatory Guide 8.31
o White Mesa Mill SOP-PBL-RP-3
o Utah Admini strative Code R313 -15
o ANSI Standard N323A
Personnel Contacted
Ron Nieves Mill RSO
Dan Hillston Mill Manager
Dose Rate Instrumentation
Dose Rate Instruments Inspected:
Make Model Serial Number
No dose rate instruments were evaluated during this inspection.
Page 1 of 6
Scalers
Scalers Inspected:
Make Model Instrument S/N - Probe S/N
Ludlum 30-30 265992 - N/A
Ludlum 2200 17534-PR3174
Ludlum 29-29 146781 - 145343
Count Rate Instrumentation
Count Rate Instruments Inspected:
Make Model
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
Ludlum
L-177-61
L-177
L-177
L-3
L-177
L-l77-61
L-177-61
L-3
Instrument
Serial Number
Probe
Serial Number
264743
264740
116481
257131
264571
189581
159172
158587
RN 16489
RN 17632
PR168949
PR281518
RN19527
PR19024
RN 19528
PR281509
Page 2 of 6
Calibration of Survey, Counting Instruments and Scalers
Dose Rate Instrumentation
Dose Rate Instrument Calibration Records Inspected:
Make Model Serial Number
No dose rate instruments were evaluated during this inspection.
Count Rate Instrumentation/Sealers
Count Rate Instrument/Sealer Calibration Records Inspected:
Make Model Serial Number
Ludlum L-177-61
Ludlum L-177
Ludlum L-177
Ludlum L-3
Ludlum L-177
Ludlum L-177-61
Ludlum L-177-61
Ludlum
Ludlum 30-30
Ludlum 2200
Ludlum 29-29
264743
264740
116481
257131
264571
189581
159172
158587
265992
17534
146781
Page 3 of 6
1) Were all inspected instruments calibrated prior to use? (SOP-PBL-RP-3)
Yes _<] No •
Comments: All inspected instruments were in calibration and were appropriately labeled with a current
calibration sticker.
2) Were all inspected instruments appropriately function checked prior to use? (SOP-PBL-RP-3)
Yes _3 No •
Comments: Beta-gamma and alpha instruments are checked daily prior to use. Personnel monitor function
checks are documented on a daily log: beta-gamma and alpha material/vehicle release instruments are
documented on the release point's daily vehicle scan sheet. Scalers are efficiency checked monthly and
documented on the Area Airborne Concentration Efficiencies. Information and Data Sheet.
3) Were all inspected beta-gamma instruments function checked using a 90Sr/Y source?
(SOP-PBL-RP-3.1.4.1 Step 1)
Yes • No IE
Comments: Beta-Gamma instruments (Ludlum Model 3 S/N's 237483 and 266292) were function checked
using a 137Cs source.
See Additional Observations and Findings below.
4) Were any instruments found being used with a probe other than what the meter was calibrated with?
Yes • No E
Comments: All probe/instrument combinations observed in the field matched the combinations documented on
their respective calibration certificates.
Page 4 of 6
5) Were any instruments observed being used with any physical damage such as defective cords or
light leaks?
Yes • No [>_
Comments: All inspected instrumentation appeared to be in satisfactory physical condition.
6) Were all calibration records inspected, for instruments currently being used, complete and accurate?
Yes _3 No •
Comments: All inspected instruments were calibrated by Ludlum Instruments and were found to be complete
and accurate.
7) Were all inspected instrument calibrations performed using NIST traceable sources?
(ANSI N323A)
Yes [__] No •
Comments: All calibration certificates contained notation attesting to NIST traceable sources being used.
8) Were all instrument calibration records filed with previous records on the same instrument and readily
retrievable? (ANSI N323A § 4.5)
Yes [X] No •
Comments: Each inspected instrument's calibration certificates were stored in a file folder particular to that
instrument. The folder's contained all previous calibration certificates for each instrument.
Page 5 of 6
Additional Observations and Findings:
Comments: Inspection Item 3: The White Mesa Mill's Radiation Protection Manual. Section 3.1.4.1,
Step 1 states: "Turn the instrument on and place the calibrated beta/gamma (SrY)-90 check source
on the face of the detector. " The inspection found that beta-gamma instruments are function
checked using the Mill's Cs-137 #2 check source which is contrary to the procedural requirement.
However, the inspector's opinion is that there is no consequence to using the cesium-1.37 check
source. The daily function check's purpose is to verify the instrument's efficiency and its ability to
accurately determine radiation levels. Whether a Sr-Y or Cs source is used, the ability of the meter
to consistently and accurately measure the source's activity is what needs to be evaluated. What is
important, is that the same check source be used daily to verify consistent readings. The inspector
recommended to the Mill staff that they amend the language in their Radiation Protection Manual to
reflect using the cesium source or to reference using "an appropriate beta-gamma source" for daily
beta-gamma instrument function checks. No violation is recommended for this discrepancy.
Page 6 of 6
P&( GM
White Mesa Mill - Standard Operating Procedures
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3
Date: 04/14 Revision: EFR 7
Page 1 of 14
3.0 EQUIPMENT/CALIBRATION
All radiation detection instruments used at the Mill are sent to a qualified independent
laboratory for calibration every six months. If necessary, Radiation Safety Staff can use
the procedures outlined below to verify calibration.
3.1 Counters/Detectors
3.1.1 General
All radiation detectors require determination of detector optimal voltage performance or
plateau operating point. The graph of voltage applied to a detector versus detector
response is referred to as a plateau curve. The plateau curve typically has two rapidly
sloping sections and a stable, flat region. The optimal operating point is typically located
at the beginning of the flat, or flatter, section of the graph. The plateau curve is specific
for a particular detector and its accompanying readout, or measuring meter, and may vary
over time depending upon electronic component condition.
The equipment used to determine detector plateau curves includes:
1. Appropriate radiation sources
2. Electrostatic voltmeter
3. Radiation detecting instrument
4. Graph paper
5. Manufacturer's technical manual
The procedure is:
1. Ensure instrument batteries are fresh or fully charged, if applicable.
2. Turn the instrument on.
3. Adjust the instrument voltage control starting at voltage of 600 using electrostatic
voltmeter to monitor voltage setting.
4. Expose detector to a radiation source applicable to the type of detector and in the
appropriate setting.
5. Record voltage and instrument response for each adjustment of voltage applied;
increments of 50 volts are adequate.
F:\Mill SOP Master Copy\Book 09_Radiation Prot. Manual 07 License Renewal\EFR SecO AppD RPM WMMSOP rev 7.doc
(
White Mesa Mill Standard Operating Procedures
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3
Date: 04/14 Revision: EFR 7
Page 2 of 14
6. Repeat steps 4 and 5 until instrument response rapidly increases versus voltage level.
At this point, the detector is approaching potential differentials across the electrode
that may damage the detector.
7. Graph instrument response versus voltage applied.
8. Set equipment high voltage control to the optimum operating point. Record on graph
voltage selected.
9. Retain graph with calibration records.
3.1.2 Function Checks
Calibration function checks are required prior to use of radiation detection instruments
used at the Mill for the purpose of verifying that the instruments are operating at the same
efficiency as when they were calibrated by the calibration laboratory (i.e., within ±10%).
See section 3.1.3.1 for frequency. Function checks are also used for verifying
repeatability, reliability, and comparability of an instrument's measurements from one
period to another. By performing function checks for extended time periods, or on a
larger sample size, these goals are met.
Function checks involve two basic elements:
(1) calibration laboratory efficiency is compared to the instrument's efficiency on the
date of the function check; and
(2) the function check is verified with a check source having similar isotopic
composition as the one that was used by the calibration laboratory to calibrate the
instrument.
Function checks are made for all types of radiation survey instruments. The basic
principle in performing a function check is measuring the radiation field using a survey
instrument against a known amount of radiation from a calibrated source. These
measurements are made for the specific type of radiation occurring. For example, when
performing a beta/gamma survey, the instrument function check is performed using a
beta/gamma check source, such as a (SrY)-90. When performing an alpha survey, use an
alpha check source, such as Th-230 or Pu-239 for performing the function check.
A number of radiation detection instruments are used at the Mill. An Instrument Users
Manual for each instrument is maintained in the calibration files, together with calibration
documentation. The Users Manuals are to be considered the primary reference for
operating a particular instrument. This Standard Operating Procedure (SOP) is not
intended to replace the Users Manual, but rather to supplement the Manual by providing
steps to be performed for function checks. Before operating an instrument, personnel
F:\Mill SOP Master CopyVBook 09_Radiation Prot. Manual 07 License Renewal\EFRS<xt3 AppD RPM WMMSOP rev 7.doc
White Mesa Mill Standard Operating Procedures
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3
Date: 04 14 Revision: EFR 7
Page 3 of 14
should read the Users Manual and become familiar with the instrument's operation,
capabilities, and special features. Personnel will also receive on the job training on each
instrument.
Alpha particles travel very short distances in the air due to their high ionization ability -
typically V* to Vz inch. Due to this limitation, alpha monitoring must be done at a distance
of lA inch or less between the detector face and the source. Alpha monitoring, to be
consistent, requires ensuring a consistent distance be utilized between the detector face
and the source. Alpha detectors read out in counts per minute (cpm). A correlation
relationship, known as the efficiency factor, between the meter response and the actual
disintegration rate of the source is used to determine actual calibration of the meter.
Radioactivity is measured in curies (Ci), which, by definition, is 3.7 x 1010 disintegrations
per second (dps), or 2.2 X 1012 disintegrations per minute (dpm). Another measurement
unit is the Becquerel, or one dps. Alpha radiation is usually monitored as dpm, per
surface area measured.
Radiation survey equipment used at the Mill for alpha surveys are listed in Appendices 1
and 2,
3.1.3.1 Calibration and Function Check Frequency
The frequency of calibration is specified in individual instrument user manuals and
manufacturer's specifications.
During production periods, the following frequencies are observed for calibration and
function checks of radiation detection instruments:
3.1.3 Alpha Monitors
1.
2.
3.
4.
5.
Employee scans
Radon progeny
Respirator checks
Area fixed scans
Area wipe scans
Type
Calibration
Frequency
6 month
6 month
6 month
6 month
6 month
Daily or each use
Daily or each use
Daily or each use
Daily or each use
Function
Checks
5 days/week
During non-production periods, the following frequencies are observed:
1. Employee scans
Type
Calibration
Frequency
6 month
Function
Checks
bi-monthly
F:\Mill SOP Master CopyVBook 09_Radiation Prot. Manual.07 License Renewal\EFR SecU AppD RPM WMMSOP rev 7.doc
White Mesa Mill - Standard Operating Procedures
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3
Date: 04/14 Revision: EFR 7
Page 4 of 14
2.
3.
4.
5.
Radon progeny
Respirator checks
Area fixed scans
Area wipe scans
6 month
6 month
6 month
6 month
Daily or each use
Daily or each use
Daily or each use
Daily or each use
3.1.3.2 Function Check Procedures - Alpha Counters and Scaler Instruments
The following steps will be used for function checks for alpha counters and alpha scaler
instruments.
1. Turn the instrument on and place a calibrated alpha check source in the detector
holder or on the face of the detector.
2. Count the source for 1 minute and record this value in cpm.
3. Repeat step 2 four more times.
4. Average the five readings and divide the average in cpm by the known activity on the
alpha source. This is the efficiency of the instrument and detector.
5. Compare this efficiency with the efficiency obtained from the calibration lab. If the
efficiency comparison is within ±10% deviation the instrument is acceptable for use,
otherwise if not the instrument needs to be recalibrated.
6. Proceed with monitoring activities.
3.1.3.4 Calibration Procedures
All radiation detection instruments used at the Mill are sent to a qualified offsite
laboratory every six months for calibration. However, if additional onsite calibration is
required for alpha meters, the calibration procedures are:
1. Set the detector high voltage at the prior determined operating point using an
electrostatic voltmeter.
2. For counter/sealers (radon progeny/wipes), close the detector, without source present,
obtain a reading for a set time. This is a background reading.
3. Place a calibrated source for the type of radiation being measured in the source holder
and obtain reading.
F:\Mill SOP Master CopyVBook 09_Radiation Prot. Manual 07 License RenewalVEFR\Sect3 AppD RPM WMMSOP rev 7.doc
White Mesa Mill - Standard Operating Procedures Date: 04/14 Revision: EFR 7
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3 Page 5 of 14
4. Observe the counts per minute for both the background and the source.
5. Subtract the background value in cpm from the actual instrument value in cpm to
obtain a net cpm.
6. Divide the net cpm value by the known dpm of the source. This is the percentage
efficiency of the instrument system for this energy source.
7. By dividing 100 by this efficiency, an efficiency factor is obtained.
8. Dpm equals the cpm divided by the efficiency of the instrument detector system:
Note: 1 curie - 2,22 E + 12 dpm
1 microcurie = 2.22 E + 6 dpm
1 picocurie = 2.22 dpm
3.1.3.5 Onsite Electronic Calibration of Alpha Meters
Electronic calibration basically consists of the steps described below:
1. Connect survey instrument to be calibrated to the model 500.
2. Turn both instruments on.
3. Record high voltage reading on model 500.
4. Set cpm and the range multiplier on the model 500 to the desired meter deflection.
The model 500 frequency controls consist of the three-digit readout, range selector,
coarse tuning knob, and the fine tuning knob. The three-digit readout is in cpm times
the frequency multiplier.
5. Calibrating survey instruments in cpm:
A. Set model 500 frequency to value that will provide a V* meter deflection on the
survey instrument's highest count scale. Set pulse height/amplitude to twice
instrument input sensitivity.
B. Adjust the range calibration potentiometer on the survey meter to provide correct
reading record.
C. De-code model 500 frequency to next lower value; then do the same for the
survey instrument.
F:\Mill SOP Master Copy\Book 09_Radiation Prot. Manual\07 License Renewal\EFR\Sect3 AppD RPM WMMSOP rev 7.doc
White Mesa Mill Standard Operating Procedures Date: 04/14 Revision: EFR 7
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3 Page 6 of 14
D. Adjust the range calibration potentiometer for correct reading on survey
instrument. Record readings.
E. Repeat process until all ranges have been calibrated at VA meter deflection. Record
readings.
F. Return to highest count scale on survey meter.
G. Set model 500 for VA scale deflection readings.
H. Survey instrument should read within ± 10% of model 500 frequency. Record
readings.
1) If readings are outside of the tolerance, re-calibrate for VA meter deflection.
2) Tap instrument meter lightly to check for sticky meter. Meter tolerance is
± 3% from the initial readings to the final reading.
I. Decode M 500 to next lower scale. Check survey instruments for VA scale reading.
Record.
6. Record input sensitivity.
A. Select the most sensitive amplitude range 0-5 mv on the model 500.
B. Observe meter on survey instrument.
C. Increase pulse amplitude, switching to next higher range, if necessary, until the
rate meter indicates a stable reading (i.e., further increase of pulse amplitude does
not cause an increase in meter reading). Now, decrease pulse height until the
survey instrument meter reading drops 15 ± 5%. Record this pulse height as the
instrument sensitivity.
D. If your instrument has a gain or threshold control to set instrument sensitivity, set
pulse height on the model 500 to desired sensitivity level. Now adjust your
instrument threshold or gain control until the rate meter reading is within 85 ± 5%
of its stable reading value (see step C). Record the pulse height as instrument
sensitivity.
7. Calibrating survey instrument to cps.
A. Set frequency in model 500. Divide model 500 readings by 60 to convert to counts
per second.
F:\MiH SOP Master CopyVBook 09_Radiation Prot. Manual 07 License Renewal\EFR\Sect3 AppD RPM WMMSOP rev 7.doc
White Mesa Mill Standard Operating Procedures Date: 0414 Revision: EFR 7
SOP-PBL-RP-3
Book: Radiation Protection Manual, Section 3 Page 7 of 14
Repeat calibration steps as in item 5 above.
8. The Model 500 calibration by an outside laboratory shall be conducted annually.
Equipment utilized for beta-gamma monitoring is listed in Appendices 1 and 2.
3.1.4.1 Function Check Procedure
The following steps will be used for function checks on beta/gamma instruments:
1. Turn the instrument on and place the calibrated beta/gamma (SrY)-90 check source
on the face of the detector.
2. Let the reading stabilize to a constant value.
3. Record this value in cpm.
4. Divide this value by the known activity on the check source. This is the efficiency of
the instrument and detector.
5. Compare this efficiency to the efficiency obtained from the calibration laboratory. If
the efficiency comparison is within ±10% deviation the instrument needs is calibrated
if not the instrument needs to be recalibrated.
6. If this efficiency comparison is within ±10% deviation the instrument is in calibration.
7. Proceed with monitoring activities.
3.1.4.2 Calibration
All beta-gamma survey instruments are sent out every six months for calibration.
Additional calibration, if necessary, may be performed on site using techniques described
in Reg, Guide 8.30, Appendix C - Beta Correction Factor for Survey Instruments for
onsite verification performed by a qualified calibration laboratory using the indicated
source as listed in Appendix 2.
3.1.5 Gamma Monitors
Instruments for gamma measurements are listed in Appendix 1.
3.1.4 Beta-gamma Monitors
F:\Mill SOP Master CopyVBook09 Radiation Prot. Manual.07 License RenewalVEFR Sect3 AppD RPM WMMSOP rev 7.doc
UT
IA.1
Date: f^LJl
Daily Vehicle Scan for Vehicles Leaving the Restricted Area
License/
Container #
Operator
ParAey Trucking
1-
Truck/Tires
Total Alpha
dpm/100cm!
Em
Rem. Alpha
dpm/100cm2
Beta/Gamma
pVy
mr/hr
£ 0 0&
Done By
Mi
Removable alpha -
Fixed alpha -
Beta-Gamma -
1000 dpm/100cm2
5000 dpm/100cm2 average
15000 dpm/100cm2 maximum
0.2 mr/hr @ 1 cm average
1.0 mr/hr @ 1 cm maximum
Alpha Meter
Model # 3
SN jftsr?
Cal. Date 8 Jct/l./*/
Com: 3JM
Th-230
Efficiency;
Factor: H- 9
Bkg:_
MDA
Beta-Gamma
Model # 3
SN 0.31^23
Cal Date /V/W4r./V
Cs-137#2
@ JCJJJ tim iSjff&QJpnr, Reading S-^hR)HR.
or.. 9-3.1% Bkq 0.t^tnRjuf(
31 i/i.
Comments:
Date: S'-^'lH
Daily Vehicle Scan for Vehicles Leaving the Restricted Area
License/
Container #
Operator Truck/Tires
Total Alpha
dpm/100cm2
Rem. Alpha
dpm/100cm2
Beta/Gamma
p/y
mr/hr Done By
Removable alpha •
Fixed alpha -
Beta-Gamma -
1000 dpm/100cm2
5000 dpm/100cm2 average
15000 dpm/100cm2 maximum
0.2 mr/hr @ 1 cm average
1.0 mr/hr @ 1 cm maximum
Alpha Meter
Model* 3
SN >Q)2I
Cal. Date 1 ft^Alltf
Cpm: 3SOO
Th-230@?i
Efficiency: X^-
Factor H- %
Bkg: ^0
/ %
Beta-Gamma
Model # 3
SN ftkfc^k
Cal Date ^.7 IcMr,. M
Cs-137#2
Reading lc\ Ar/nr
Bkg p cuVrjttr
MDA: ll 1>
Comments: ^CNY^<\ £-OA£L
Area Airborne Concentration Instrument Efficiencies, Information, and Data Sheet
May 2014
DAC Nu
ORE
LEACH
CCD
SX
PRECIP
PCKG.
TAILS
RADON
CaF2 Ore
UF4 Leach
Calcine Ore
KFOre
UF4 0re
2929 LLD=
Regen
Regen Leach
mbers
6.00E-11
1.10E-10
1.20E-11
1.20E-11
5.00E-10
2.20E-11
1.70E-11
3.30E-01
8.00E-12
3.70E-10
1.30E-11
2.60E-10
3.00E-10
7.48E-13
4.20E-10
4.60E-10
Ludlum Model 2929 Efficiency Check
Cnt. Time:
Background
Count No. Reading
1 10.90
2 12.10
3 12.50
60 min. bkgd. Value 1.57
Total Bkgd.
Bkgd. Ave. 11.83
Source DPM
Efficiency
Standard Deviation 0.83
Efficiency Factor
Volume Collected
Factor to Convert
DPM to uCi/CC
10 Cnt. Time:
Efficiency Check
Count No.
1
2
3
Total CPM
CPM Ave.
Source Ser. No.
10 Min
Reading
3497.00
3511.00
3492.00
10500.0
3500.00
S-2349
16700
20.96%
9.85
4.77
2.40E+06
2.22 E+6
2Pi Laboratory Eff.at voltage with Pu-239:
2Pi WMM Eff.at voltage with Pu-239:
85.10%
74.21%
2200 LLD=: 1.02E-12
Laboratory Calibration Efficiency Check
Reading
Count No. 2929 2200
1 27698 30188.00
2 28437 30266.00
3 28470 30198.00
Ludlum Model 2200 Efficiency Check
Cnt. Time:
Background
Count No.
1
2
3
10 Cnt. Time: 10 Min
Efficiency Check
Reading Count No. Reading
26.20 1 3703.00
26.10 2 3744.00
26.00 3 3720.00
Total Bkgd.
Bkgd. Ave.
Average 28202 30217 60 min. bkgd.
Source DPM 38000 38000 Source DPM
4Pi Efficiency 74.21% 79.52% Efficiency
at W M M Standard Deviation
Factor
Volume Collected
Factor to Convert
DPM to uCi/CC
2Pi Laboratory Eff.at voltage with Pu-239:
2Pi WMM Eff.at voltage with Pu-239:
78.3
26.10
2.65
0.10
Total CPM
CPM Ave.
Source Ser. No.
11167.0
3722.33
S-2349
16700
22.29%
20.60
4.49
2.40E+06
2.22 E+6
87.30%
79.52%
Notes:
The weather for sampling this month was very windy, some rain but mostly windy.
For May 2014
Ludlum Model 3030 Efficiency Check
Calibration Check
Count Number CPM
1 26826
2 26778
3 26808
Cnt. Time: 10 Minutes
Background
Count No. CPM
1 1.00
2 1.00
3 1.00
Cnt. Time: 10 Minutes
Efficiency Check
Count No. CPM
1 3370.0
2 3370.0
3 3332.0
Total CPM
CPM Ave.
Source Isotope
Source Serial No.
4 Pi Source DPM
4Pi Efficiency
Standard Deviation
80412.00
26804
Sry-90
98SR470
39300
68.20%
24.25
2929 LLD= 6.92E-10 uCi/ml
that at White Mesa Mill on this date.
Total CPM
CPM Ave.
60 Min. Bkgd.
3
1.00
1.3
Source DPM
Efficiency
Standard Deviation 0.00
Efficiency Factor
MDA 10.21
Volume Collected
Factor to Convert DPM to uCi/CC
2Pi Laboratory Eff.at voltage with Sry-90
2Pi WMM Eff.at voltage with Sry-90:
10072.00
3357.33
S-2349
16700
20.10%
21.94
4.97
36.61
2.00E+01
2.22 E+6
85.10%
68.20%