ML24276A077
| ML24276A077 | |
| Person / Time | |
|---|---|
| Site: | University of New Mexico |
| Issue date: | 01/28/2025 |
| From: | Michael Brown NRC/NRR/DANU/UNPO |
| To: | Willis C Univ of New Mexico |
| References | |
| 50-252/OL-25-01 OL-25-01 | |
| Download: ML24276A077 (1) | |
Text
Carl Willis, Chief Reactor Supervisor Nuclear Engineering Department 1 University of New Mexico, MSC-01-1120 Albuquerque, NM 87131-0001
SUBJECT:
EXAMINATION REPORT NO. 50-252/OL-25-01, UNIVERSITY OF NEW MEXICO
Dear Carl Willis:
During the week of January 13, 2025, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your University of New Mexico research reactor. The examination was conducted according to NUREG-1478, "Operator Licensing Examiner Standards for Research and Test Reactors," Revision 2. Examination questions and preliminary findings were discussed with those members of your staff identified in the enclosed report at the conclusion of the examination.
In accordance with Title 10 of the Code of Federal Regulations, Section 2.390, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. Should you have any questions concerning this examination, please contact Amy Beasten at 301-415-8341 or via email at Amy.Beasten@nrc.gov.
Sincerely, Tony Brown, Chief Non-Power Production and Utilization Facility Oversight Branch Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation Docket No. 50-252
Enclosures:
- 1. Examination Report No. 50-252/OL-25-01
- 2. Written examination cc: w/enclosures to GovDelivery Subscribers January 28, 2025 Signed by Brown, Tony on 01/28/25
ML24276A077 NRR-079 OFFICE NRR/DANU/UNPO/CE NRR/DANU/UNPO/OLA NRR/DANU/UNPO/BC NAME ABeasten NJones TBrown DATE 1/28/2025 1/28/2025 1/28/2025 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.:
50-252/OL 25-01 FACILITY DOCKET NO.:
50-252 FACILITY LICENSE NO.:
R-102 FACILITY:
University of New Mexico EXAMINATION DATES:
Week of January 13, 2025 SUBMITTED BY:
SUMMARY
During the week of January 13, 2025, the NRC administered operator licensing examinations to one Reactor Operator (RO) candidate. The RO candidate passed the operating examination but failed Category B and Category C of the written examination and was an overall written examination failure.
REPORT DETAILS 1.
Examiner:
Amy E. Beasten, PhD, Chief Examiner, NRC 2.
Results:
RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 0/1 0/0 0/1 Operating Tests 1/0 0/0 1/0 Overall 0/1 0/0 0/1 3.
Exit Meeting:
Amy E. Beasten, PhD, NRC Chief Examiner Carl Willis, Chief Reactor Supervisor, University of New Mexico Rowdy Davis, Reactor Administrator, University of New Mexico Prior to administration of the written examination, based on facility comments, adjustments were accepted. Comments provided corrections and additional clarity to questions/answers and identified where changes were appropriate based on current facility conditions.
Upon completion of all operator licensing examinations, the NRC examiner met with facility staff representatives to discuss the results. At the conclusion of the meeting, the NRC examiner thanked the facility for their support in the administration of the examination.
1/16/2025 Name, Chief Examiner Date University of New Mexico Operator Licensing Examination Week of January 13, 2025 U. S. NUCLEAR REGULATORY COMMISSION NON-POWER REACTOR LICENSE EXAMINATION FACILITY:
University of New Mexico REACTOR TYPE:
AGN DATE ADMINISTERED:
January 14, 2025 CANDIDATE:
INSTRUCTIONS TO CANDIDATE:
Answers are to be written on the Answer sheet provided. Attach all Answer sheets to the examination. Point values are indicated in parentheses for each question. A 70% in each category and a 70% overall are required to pass the examination. Examinations will be picked up three (3) hours after the examination starts.
CATEGORY VALUE
% OF TOTAL CANDIDATE'S SCORE
% OF CATEGORY VALUE CATEGORY 18.00 33.0 A. REACTOR THEORY, THERMODYNAMICS, AND FACILITY OPERATING CHARACTERISTICS 18.00 33.0 B. NORMAL AND EMERGENCY OPERATING PROCEDURES AND RADIOLOGICAL CONTROLS 18.00 33.0 C. FACILITY AND RADIATION MONITORING SYSTEMS 54.00 TOTALS FINAL GRADE All work done on this examination is my own. I have neither given nor received aid.
Candidate's Signature
NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS During the administration of this examination the following rules apply:
1.
Cheating on the examination means an automatic denial of your application and could result in more severe penalties.
2.
After the examination has been completed, you must sign the statement on the cover sheet indicating that the work is your own and you have neither received nor given assistance in completing the examination. This must be done after you complete the examination.
3.
Restroom trips are to be limited and only one candidate at a time may leave. You must avoid all contacts with anyone outside the examination room to avoid even the appearance or possibility of cheating.
4.
Use black ink or dark pencil only to facilitate legible reproductions.
5.
Print your name in the blank provided in the upper right-hand corner of the examination cover sheet and each Answer sheet.
6.
Mark your Answers on the Answer sheet provided. USE ONLY THE PAPER PROVIDED AND DO NOT WRITE ON THE BACK SIDE OF THE PAGE.
7.
The point value for each question is indicated in [brackets] after the question.
8.
If the intent of a question is unclear, ask questions of the examiner only.
9.
When turning in your examination, assemble the completed examination with examination questions, examination aids and Answer sheets. In addition turn in all scrap paper.
10.
Ensure all information you wish to have evaluated as part of your Answer is on your Answer sheet. Scrap paper will be disposed of immediately following the examination.
11.
To pass the examination you must achieve a grade of 70 percent or greater in each category and a 70 percent or greater overall.
12.
There is a time limit of three (3) hours for completion of the examination.
Category A: Reactor Theory, Thermodynamics, & Facility Operating Characteristics A N S W E R S H E E T Multiple Choice (Circle or X your choice)
If you change your answer, write your selection in the blank.
A01 a b c d ___
A02 a b c d ___
A03 a b c d ___
A04 a b c d ___
A05 a b c d ___
A06 a b c d ___
A07 a b c d ___
A08 a b c d ___
A09 a b c d ___
A10 a b c d ___
A11 a___ b___ c___ d___
A12 a b c d ___
A13 a b c d ___
A14 a b c d ___
A15 a b c d ___
A16 a b c d ___
A17 a b c d ___
A18 a b c d ___
(***** END OF CATEGORY A *****)
Category B: Normal/Emergency Operating Procedures and Radiological Controls A N S W E R S H E E T Multiple Choice (Circle or X your choice)
If you change your answer, write your selection in the blank.
B01 a b c d ___
B02 a b c d ___
B03 a b c d ___
B04 a b c d ___
B05 a b c d ___
B06 a b c d ___
B07 a b c d ___
B08 a b c d ___
B09 a b c d ___
B10 a___ b___ c___ d___
B11 a b c d ___
B12 a b c d ___
B13 a b c d ___
B14 a b c d ___
B15 a b c d ___
B16 a___ b___ c___ d___
B17 a b c d ___
B18 a b c d ___
(***** END OF CATEGORY B *****)
Category C: Plant and Radiation Monitoring Systems A N S W E R S H E E T Multiple Choice (Circle or X your choice)
If you change your answer, write your selection in the blank.
C01 a b c d ___
C02 a b c d ___
C03 a b c d ___
C04 a b c d ___
C05 a b c d ___
C06 a b c d ___
C07 a___ b___ c___ d___
C08 a b c d ___
C09 a b c d ___
C10 a b c d ___
C11 a b c d ___
C12 a b c d ___
C13 a b c d ___
C14 a b c d ___
C15 a b c d ___
C16 a b c d ___
C17 a b c d ___
C18 a b c d ___
(***** END OF CATEGORY C *****)
(********** END OF EXAMINATION **********)
EQUATION SHEET
=
+
DR - Rem, Ci - curies, E - Mev, R - feet 1 Curie = 3.7 x 1010 dis/sec 1 kg = 2.21 lb 1 Horsepower = 2.54 x 103 BTU/hr 1 Mw = 3.41 x 106 BTU/hr 1 BTU = 778 ft-lb
°F = 9/5 °C + 32 1 gal (H2O) 8 lb
°C = 5/9 (°F - 32) cP = 1.0 BTU/hr/lb/°F cp = 1 cal/sec/gm/°C
2 2
max
P 1
sec 1.0
eff
T UA H
m T
c m
Q P
sec 10 1
4
2 1
1 1
2 1
eff eff K
CR K
CR
eff SUR 06 26
te P
P 0
eff K
S S
1
2 2
1 1
CR CR
0 1
P P
1 2
1 1
CR CR K
M eff
)
(
0 10 t
SUR P
P 2
1 1
1 eff eff K
K M
eff eff K
K SDM
1 2
1 1
2 eff eff eff eff K
K K
K
693
.0 2
1 T
eff eff K
K 1
2 2
2 2
1 1
d DR d
DR
t e
DR DR
0
1 2
1 2
2 2
Peak Peak
2 6
R n
E Ci DR
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.01
[1.0 point]
Which ONE of the following statements best describes the function of a reflector around the core?
- a. Reduce the ratio of peak flux to the flux at the edge of the core fuel area.
- b. Increase the ratio of flux at the edge of the core fuel area to peak flux to shorten irradiation times for periphery or external experiments.
c.
Reduce the power output of a reactor by slowing fission neutrons to thermal energies.
- d. Provide additional radiological shielding to protect personnel working near the reactor.
QUESTION A.02
[1.0 point]
Which ONE of the following factors in the six-factor formula accounts for the probability that a fast neutron will be slowed to thermal energies without being absorbed in the fuel?
- a. Thermal utilization factor (f)
- b. Fast fission factor ()
c.
Resonance escape probability (p)
- d. Reproduction factor ()
QUESTION A.03
[1.0 point]
The current count rate is 190 cps. An experimenter inserts an experiment into the core and the count rate decreases to 125 cps. If the initial Keff was 0.987, what is the worth of the experiment?
- a. + 0.013
- b. - 0.013 c.
+ 0.007
- d. - 0.007
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.04
[1.0 point]
Which ONE of the following statements best describes radiative capture?
a.
A neutron is absorbed by a nucleus to form a compound nucleus, which emits a lower kinetic energy neutron, and returns to ground state by gamma emission (n, n).
b.
A neutron interacts with a nucleus to form a compound nucleus, which decays to ground sate by gamma emission (n, ).
c.
A neutron is absorbed by a nucleus, leading to the immediate emission of a charged particle like an alpha particle or proton (n, p).
d.
A neutron is absorbed by a nucleus, which splits into two smaller nuclei, releasing additional neutrons and energy.
QUESTION A.05
[1.0 point]
Which ONE of the following statements best describes the significance of delayed neutrons in reactor operation?
a.
Delayed neutrons are emitted during fission and are essential to achieve and maintain reactor criticality.
b.
Delayed neutrons are important in lengthening the neutron generation time to ensure proper control of the reactor during power increases.
c.
Delayed neutrons ensure that there is a sufficient neutron population to provide visible indication of neutron level during start-up and shutdown.
d.
Delayed neutrons ensure there is a sufficient neutron population to overcome the effects of fission product poisoning following a shutdown.
QUESTION A.06
[1.0 point]
Given a source strength of 300 neutrons per second (N/sec) and a multiplication factor of 0.75, which ONE of the following is the expected stable neutron count rate?
a.
1,000 N/s b.
1,200 N/s c.
12,000 N/s d.
15,000 N/s
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.07
[1.0 point]
Which ONE of the following statements is best describes the behavior of the microscopic cross-section of fission (f) for U-235?
a.
It increases linearly with increasing neutron energy.
b.
It has resonance peaks which expand as fuel temperature increases.
c.
The values are highest for the thermal neutron energy range.
d.
It remains constant for all neutron energies.
QUESTION A.08
[1.0 point]
Which ONE of the following describes when a reactor is supercritical?
a.
keff > 1; < 1 b.
keff < 1; > 1 c.
keff > 1; < 0 d.
keff > 1; > 0 QUESTION A.09
[1.0 point]
Which ONE of the following statements best describes the macroscopic cross-section ()?
a.
The probability of a given reaction occurring per unit length of travel of the neutron, with units of cm-1.
b.
The probability of a given reaction occurring between a neutron and a nucleus, with units of cm-1.
c.
The probability of a given reaction occurring between a neutron and a nucleus, with units of cm2.
d.
The probability of a given reaction occurring per unit length of travel of the neutron, with units of cm2.
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.10
[1.0 point]
The moderator temperature coefficient for a reactor is -0.00095 k/k/oF. What is the total reactivity change caused by a temperature increase of 15oF?
a.
+ 0.1425 b.
- 0.1425 c.
+ 0.0143 d.
- 0.0143 QUESTION A.11
[1.0 point, 0.25 each]
For each scenario in Column A, identify the direction in Column B that control rods would need to be moved at UNM to maintain constant reactor power. Answers in Column B may be used once, more than once, or not at all.
Column A a.
Pool water temperature increase b.
Buildup of Xe-135 c.
Burnup of U-235 d.
Buildup of Ar-41 Column B
- 1. Insert
- 2. Withdraw
- 3. No movement QUESTION A.12
[1.0 point]
Which ONE of the following statements best describes the effective multiplication factor, keff?
a.
The ratio of neutrons produced by fast fission in one generation to the number of neutrons lost through leakage in the preceding generation.
b.
The ratio of neutrons produced by fission in one generation to the number of thermal neutrons lost through leakage in the preceding generation.
c.
The ratio of neutrons produced by fission in one generation to the number of neutrons lost through absorption and leakage in the preceding generation.
d.
The ratio of neutrons produced by fission in one generation to the number of neutrons lost through absorption in the preceding generation.
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.13
[1.0 point]
A reactor is shutdown by 2.5% k/k. If control rods are inserted until the count rate increases by a factor of 7, and the reactor is still subcritical, what is the new Keff?
a.
0.958 b.
0.962 c.
0.976 d.
0.997 QUESTION A.14
[1.0 point]
Which ONE of the following best describes the reason that, following a reactor scram from full licensed power, indicated reactor power does not immediately decay to zero?
a.
Core neutron population is sustained by neutrons from the installed neutron source.
b.
Core neutron population is sustained by the delayed neutron precursors.
- b. In-core nuclear instrumentation lags the prompt drop.
d.
Core neutron population is sustained by spontaneous fission of U-235.
QUESTION A.15
[1.0 point]
All of the following statements regarding Xe-135 are true EXCEPT:
a.
After a power decrease, Xe-135 concentrations will initially decrease due to burnout and will peak at a lower equilibrium value.
b.
Following a reactor shutdown, Xe-135 concentrations will increase due to the decay of I-135.
c.
Xe-135 is produced directly from fission and is removed from the core by neutron absorption.
d.
After a power increase, Xe-135 concentrations will initially decrease due to increased burnout and will peak at a higher equilibrium value.
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.16
[1.0 point]
Approximately _____ MeV is released instantaneously per fission of U-235.
a.
157 b.
190 c.
200 d.
250 QUESTION A.17
[1.0 point]
Elastic scattering is defined as:
a.
The process in which a neutron strikes a ground state nucleus, the neutron is re-emitted and the nucleus remains in the ground state.
b.
The process in which a neutron strikes a ground state nucleus to form a compound nucleus.
A neutron of lower kinetic energy is emitted, leaving the nucleus in an excited state, which decays by gamma emission.
c.
The process in which a neutron strikes a ground state nucleus to form a compound nucleus, with the neutron being re-emitted.
d.
The process in which a neutron collides with a nucleus causing the nucleus to split into smaller particles.
QUESTION A.18
[1.0 point]
Which ONE of the following factors in the six-factor formula is NOT affected by the enrichment of U-235 in the fuel?
a.
Resonance escape probability (p) b.
Reproduction factor ()
c.
Thermal utilization factor (f) d.
Fast non-leakage probability (Lf)
(***** END OF CATEGORY A *****)
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.01
[1.0 point]
In accordance with the UNM Emergency Plan, in the event of a building evacuation due to abnormally high radiation levels, all of the following actions should be taken by the reactor operator EXCEPT:
a.
Evacuating with the operations logbook and portable survey meter(s).
b.
Ensuring all personnel have evacuated.
c.
Notifying emergency services by dialing 9-1-1 from any phone.
d.
Ensuring that exhaust fans have been turned on to maintain negative differential pressure.
QUESTION B.02
[1.0 point]
In accordance with UNM Operating Procedures, which ONE of the following evolutions would be considered a NONROUTINE operation?
a.
Performance of control rod calibrations following normal maintenance.
b.
Operation with an approved access port experiment of worth 0.25% k/k.
c.
A 1/M experiment performed for the Reactor Laboratory Course.
d.
Addition of a new experiment of worth 0.2% k/k which causes a reactor power increase from 1 W to 2 W.
QUESTION B.03
[1.0 point]
What is the dose rate at 1 foot, given 85% of the decay of an 6 Curie source results in emission of a 200 keV gamma?
a.
0.612 R/hr b.
1.08 R/hr c.
6.12 R/hr d.
10.8 R/hr
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.04
[1.0 point]
In accordance with UNM Technical Specifications, which ONE of the following experiments would be permissible?
a.
A singly encapsulated vial of U-235 suspended in the reactor tank.
b.
A cylinder of stainless-steel plated cadmium having an estimated reactivity worth of -0.60 k/k in an access port.
c.
A doubly encapsulated vial containing 2.5mg of C-4 explosive in an access port.
d.
A doubly encapsulated vial of Co-60 that, if opened in the lab after being irradiated, would cause a total effective dose equivalent to an experimenter of 1 rem.
QUESTION B.05
[1.0 point]
In accordance with the UNM Emergency Plan, which ONE of the following individuals has the authority to declare a Notification of Unusual Event (NOUE)?
a.
UNM Chief of Police b.
Reactor Safety and Recovery Operations Coordinator (ROC) c.
Director of Emergency Operations (DEO) d.
Radiation Safety and Dose Assessment Coordinator (DAC)
QUESTION B.06
[1.0 point]
An irradiated sample has a dose rate of 5.0 rem/hr as indicated at a distance of 1 foot from the sample. How far from the irradiated sample will the dose rate read 100 mrem/hr?
a.
7.07 ft b.
4.86 ft.
c.
3.87 ft d.
2.24 ft
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.07
[1.0 point]
In accordance with Operating Procedure 2, Start-Up Check-Out Procedure, which ONE of the following locations is NOT required to be surveyed for radiation prior to commencing reactor start up?
a.
Reactor top b.
Access ports c.
Reactor access shield doors d.
Experimenter workstations QUESTION B.08
[1.0 point]
In accordance with UNM Technical Specifications, which ONE of the following surveillance requirements may NOT be deferred during an extended reactor shutdown?
a.
Shutdown margin determination.
b.
Control rod scram times.
c.
Channel test of the seismic displacement interlock.
d.
Calibration of the portable radiation survey instruments assigned to the reactor facility.
QUESTION B.09
[1.0 point]
In accordance with 10 CFR 20.1003, which ONE of the following statements best describes the Committed Dose Equivalent?
a.
The dose equivalent to organs or tissues of reference (T) that will be received from an intake of radioactive material by an individual during the 50-year period following the intake.
b.
The sum of the effective dose equivalent for external exposures and the committed effective dose equivalent for internal exposures.
c.
The concentration of a given radionuclide in air which, if breathed by the reference man for a working year of 2,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> under conditions of light work results in one yearly intake limit.
d.
The obtained limit for the amount of radioactive material taken into the body of an adult worker by inhalation or ingestion in a year.
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.10
[1.0 point, 0.25 each]
Match the definition (reactor location?) in Column A with the term from 10 CFR 20 in Column B. Options in Column B may be used once, more than once, or not at all.
Column A a.
An area to which access can be limited by the licensee for any reason.
b.
An area accessible to individuals, where radiation levels could result in a dose equivalent of 5 mrem in 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> at 30 cm from the source.
c.
An area to which access is limited for the purpose of protecting individuals against undue risks from exposure to radiation and radioactive materials.
d.
An area accessible to individuals, where radiation levels could result in a dose equivalent of 100 mrem in 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> at 30 cm from the source.
Column B 1.
Radiation Area 2.
Controlled Area 4.
Restricted Area QUESTION B.11
[1.0 point]
In accordance with regulation _______, an operator may deviate from a license condition or Technical Specifications to ensure the health and safety of the public. The minimum level of authorization needed for this is _______.
a.
50.54(x); Senior Reactor Operator.
b.
55.59; Reactor Administrator.
c.
50.59; Reactor Safety Advisory Committee.
d.
50.47; Senior Reactor Operator.
QUESTION B.12
[1.0 point]
Which ONE of the following conditions would NOT be a reportable occurrence in accordance with UNM Technical Specifications?
a.
Manual scram bar only causes the coarse control rod to scram.
b.
No licensed operator in the control room with the key in the console.
c.
Reactor power calibration not performed during the required interval.
d.
Operating the reactor with an experiment having a reactivity worth of 0.45% k/k
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.13
[1.0 point]
In accordance with UNM Technical Specifications, Which ONE of the following conditions does NOT describe a control rod interlock (assume the reactor is shutdown)?
a.
The coarse control rod cannot be withdrawn unless both safety rods are fully withdrawn.
b.
If reactor power is below 50 x 10-6 W, none of the control rods can be moved to a more reactive position.
c.
Earthquake switch open.
d.
Shield tank temperature at 16°C.
QUESTION B.14
[1.0 point]
In accordance with UNM Technical Specifications, a Reactor Supervisor is required to be present for all of the following evolutions or activities EXCEPT:
a.
During fuel handling.
b.
When the reactor is going critical.
c.
During experiment loading or unloading.
- d. Changes in reactivity greater than 0.4% k/k.
QUESTION B. 15
[1.0 point]
In accordance with Technical Specifications, the Reactor Operations Committee will review and approve which ONE of the following activities or changes?
a.
Correction of a spelling error on the Startup Checklist procedure.
b.
A proposal to introduce a Continuous Air Monitor in the reactor room to provide continuous monitoring of radiation levels during periods of operation and shutdown.
c.
Restart following a Safety Limit violation.
d.
Introduction of a new procedure governing performance of fuel inspection.
Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.16
[1.0 point, 0.25 each]
In accordance with UNM Maintenance and Inspection Procedures and Technical Specifications, match the surveillance activity in Column A with the interval listed in Column B. Options in Column B may be used once, more than once, or not at all. Assume the reactor is in operation.
Column A a.
Channel check of Safety Channels 2 and 3 b.
Power level measuring channel calibration c.
Control rod insertion times d.
Water level scram test Column B 1.
Daily 2.
Monthly 3.
Annually QUESTION B.17
[1.0 point]
In accordance with UNM Administrative Procedures, which ONE of the following is NOT a responsibility of the Radiological Safety Officer (RSO)?
a.
Serves as the Dose Assessment Coordinator during emergency events.
b.
Represents the Radiological Control Committee on Reactor Operations.
c.
Reviews and approves all proposed changes to the operating procedures.
d.
Serves as the Emergency Director during radiological events.
QUESTION B.18
[1.0 point]
An experiment reading 7.5 rem/hr was removed from the reactor. Four hours later, it reads 900 mrem/h. What is the half-life of the experiment?
a.
1.02 hr b.
1.32 hr c.
1.98 hr d.
2.12 hr
(***** END OF CATEGORY B *****)
Category C: Facility and Radiation Monitoring Systems QUESTION C.01
[1.0 point]
In accordance with the UNM Safety Analysis Report, which ONE of the following statements best describes the sequence of events that occur on a manual scram?
a.
The safety and coarse rods will fall under gravity and all four rod carriages will drive downward automatically. When the rod carriages reach their lower limits, the OUT lights come on.
b.
All four rods will fall under gravity. The rod carriages must be driven down manually and when they reach their lower limits, the IN lights come on.
c.
The safety and fine rods will fall under gravity the rod carriages will be driven down automatically, but the coarse rod must be manually driven down. When the rod carriages reach their lower limits, the OUT lights come on.
d.
The safety and coarse rods will fall under gravity and all four rod carriages will drive downward automatically, but the fine rod must be manually driven down. When the rod carriages reach their lower limits, the IN lights come on.
QUESTION C.02
[1.0 point]
All of the following statements regarding the core fuse are correct EXCEPT:
a.
The core fuse has a higher fuel loading than the rest of the core.
b.
The core fuse will melt if the temperature rises above 100°C.
c.
The temperature in the core fuse rises twice as fast as the temperature in the core.
d.
The core fuse is a polystyrene plug that supports the upper half of the core.
QUESTION C.03
[1.0 point]
Which ONE of the following material combinations correctly describes the primary composition of the access ports where experiments or other equipment are NOT installed?
a.
Graphite, lead (Pb), and water b.
Wood, lead (Pb), and graphite c.
Wood, graphite, and Cadmium (Cd) d.
Lead (Pb), borated polyethylene, and graphite.
Category C: Facility and Radiation Monitoring Systems QUESTION C.04
[1.0 point]
In accordance with UNM Operating Procedures, which ONE of the following actions is NOT verified during Start-up Check-Out by inserting and withdrawing the check source drive?
a.
Verifying Source Drive Unit is functional.
b.
Acting as a channel check for Channels 2 and 3.
c.
Acting as a channel test of Channels 2 and 3.
d.
Verifying proper response of Limit Switch Indications.
QUESTION C.05
[1.0 point]
In accordance with the UNM Safety Analysis Report, Which ONE of the following defines the current standard loading configuration?
a.
The glory hole is empty, all access port fillers are in the normal position, and the fine control rod contains polyethylene rod sections.
b.
The glory hole is empty, a boron-lined ion chamber is inserted into access port 4, replacing half the filler. Paraffin or polyethylene fills the remaining space. The fine control rod contains normal polyethylene rod sections.
c.
The glory hole is empty, a boron-lined ion chamber is inserted into access port 4, replacing half the filler. Paraffin or polyethylene fills the remaining space. The startup source and source drive are in access port 2. The fine control rod contains normal fuel material rod sections.
d.
The glory hole is empty, all access port fillers are in the normal position, and the fine control rod contains normal fuel material rod sections. The startup source and source drive are in access port 2.
QUESTION C.06
[1.0 point]
Which ONE of the following best describes how Channel 1 operates?
a.
Channel 1 is a U-235 fission chamber lined with highly enriched U-235. Neutrons interact with the U-235 to produce fission, which ionize the fill gas producing a signal.
b.
Channel 1 is a U-238 fission chamber lined with highly enriched U-235. Neutrons interact with the U-238 to produce fission, which ionize the fill gas producing a signal.
c.
Channel 1 is a boron-lined ionization chamber. Neutrons interact with the boron lining to produce alpha particles, which ionize the fill gas producing a signal.
d.
Channel 1 is a boron-gas filled ionization chamber. Neutrons interact with the boron gas to produce alpha particles, which ionize the fill gas producing a signal.
Category C: Facility and Radiation Monitoring Systems QUESTION C.07
[1.0 point, 0.25 each]
Match the remote area radiation monitor in Column A with the Alarm set point in Column B.
Options in Column B may be used once, more than once, or not at all.
Column A a.
Checkpoint 3 b.
General lab c.
Reactor top d.
Reactor console Column B 1.
2 mR/hr 2.
10 mR/hr 3.
50 mR/hr 4.
100 mR/hr QUESTION C.08
[1.0 point]
Which ONE of the following requirements must be considered when evaluating the standard loading?
a.
Excess reactivity may not exceed 0.25% k/k.
b.
Explosive material placed in the access ports must be doubly encapsulated.
c.
Total uranium content (excluding control rods) must remain below 1,000 g.
d.
The startup source may be placed in any access port.
QUESTION C.09
[1.0 point]
In accordance with UNM Technical Specifications, which ONE of the following experiments would be considered a MOVEABLE experiment?
a.
Gold foils placed in various access ports to determine neutron flux throughout the core.
b.
A pottery sample placed in an access port for neutron activation analysis.
c.
A sealed aluminum container filled with heavy water placed in the thermal column to study the generation of tritium.
d.
An aluminum rod with a Am-Be source at the end designed to be withdrawn during reactor operation to monitor Channel 2 response times.
Category C: Facility and Radiation Monitoring Systems QUESTION C.10
[1.0 point]
Which ONE of the following chain reactions describes the method of neutron generation in the UNM startup source?
a.
241Am + 9Be 237Np + 4 + 9Be 12C + 1n + 237Np b.
241Am + 9Be 241Am + 4 + 5He 241Am + 1n + 4 + 4He c.
239Pu + 9Be 235U + 4 + 9Be 235U + 1n + 12C d.
239Pu + 9Be 239Pu + 4 + 5He 239Pu + 4 + 4He + 1n QUESTION C.11
[1.0 point]
Which ONE of the following statements best describes the operation of the UNM remote area radiation monitors?
a.
An ion chamber specifically utilizing boron to distinguish between neutrons and gammas to provide an effective biological dose rate.
b.
A Geiger Mueller detector calibrated to a specific energy to produce a dose rate.
c.
A Geiger Mueller detector that uses a bimetallic film to discriminate between high and low energy betas and gammas to produce a dose rate d.
An NaI Scintillator Detector that emits varying intensities of light based on the energy of the radioactive particle incident on the detector.
QUESTION C.12
[1.0 point]
Which ONE of the following statements best describes the fine control rod?
a.
The fine control rod contains 14.5g U-235 in polyethylene, magnetically coupled to a carriage.
b.
The fine control rod contains 14.5g U-235 in polyethylene, mechanically coupled to a carriage.
c.
The fine control rod contains 2.71g U-235 in polyethylene, magnetically coupled to a carriage.
d.
The fine control rod contains 2.71g U-235 in polyethylene, mechanically coupled to a carriage.
Category C: Facility and Radiation Monitoring Systems QUESTION C.13
[1.0 point]
Which ONE of the following statements best describes the basis for the low shield water temperature limit?
a.
Prevents thermal stress on reactor tank and core components due to large temperature fluctuations during operation.
b.
Prevents reactivity additions associated with core temperature decreases.
c.
Ensures the thermal fuse material will not degrade due to extremely low operating temperatures.
d.
Ensures the integrity of all experiments conducted at the facility.
QUESTION C.14
[1.0 point]
In accordance with UNM Technical Specifications, which ONE of the following conditions would cause an automatic reactor scram?
a.
Shield water level below 18cm from the highest point on the reactor shield tank manhole opening b.
Reactor Top Radiation Area Monitor high alarm c.
Reactor power at 5.5 W.
d.
Reactor power below 50 x10-6 W QUESTION C.15
[1.0 point]
When the signal from ________ reaches ________, the high voltage on _____ is automatically turned off.
a.
Channel 3; 5.0 x 10-9 amps; Channel 2 b.
Channel 2; 5.0 x 10-9 amps; Channel 1 c.
Channel 3; 1.0 x 10-12 amps; Channel 2 d.
Channel 2; 1.0 x 10-12 amps; Channel 1
Category C: Facility and Radiation Monitoring Systems QUESTION C.16
[1.0 point]
Which ONE of the following statements best describes how adjustments to excess reactivity can be made?
a.
Inserting gold foil into the access ports.
b.
Inserting or removing the cadmium rod in the glory hole c.
Moving the installed neutron start-up source to a different access port.
d.
Adjusting control rod travel by altering the rod top limit switch position.
QUESTION C.17
[1.0 point]
Which ONE of the following statements best describes the reason for the automatic disabling of high voltage to the start-up monitor channel during reactor operations?
a.
As reactor power increases, this detector is not a reliable indicator of reactor power due to increased gamma production.
b.
At higher reactor powers, this detector indicates off-scale high and is disabled to prevent an inadvertent reactor scram.
c.
The detector switches from pulse mode to current mode to provide a n accurate indication of reactor power above the source range.
d.
This extends the life of the detector.
QUESTION C.18
[1.0 point]
Which ONE of the following statements best describes the purpose of doubly encapsulating the active fuel section of the safety rods?
a.
It serves to isolates the fuel in the rods from the fuel in the core.
b.
It acts as the cladding of the active fuel of the control rods.
c.
It protects the active fuel section when the control rods are scrammed.
d.
It acts as shielding to maintain a constant neutron flux regardless of control rod height.
(***** END OF CATEGORY C *****)
(********** END OF EXAMINATION **********)
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics A.01 Answer:
a.
Reference:
DOE Fundamentals Handbook, Vol. 2, Module 4, p. 25 A.02 Answer:
c.
Reference:
DOE Fundamentals Handbook, Vol. 2, Module 3, p. 3 A.03 Answer:
d.
Reference:
CR1 / CR2 = (1 - Keff2) / (1 - Keff1) 190 / 125 = (1 - Keff2) / (1 - 0.987) 1.52 * (0.013) = 1 - Keff2 Keff2 = 0.980
= (Keff2 - Keff1) / (Keff2
- Keff1)
= (0.980 - 0.987) / (0.980
- 0.987)
= - 0.007 A.04 Answer:
b.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 2-28 A.05 Answer:
b.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 3-31 A.06 Answer:
b.
Reference:
CR = S / (1-k)
S = CR / (1-k)
S = 300 / (1-0.25)
S = 500 N/sec.
A.07 Answer:
c.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 2-37 A.08 Answer:
d.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 3-21 A.09 Answer:
a.
Reference:
DOE Fundamentals Handbook, Vol. 1, Module 2, p. 17 A.10 Answer:
d.
Reference:
DOE Fundamentals Handbook, Volume 2, Module 3, p. 21,
T*T
= (-0.00095 k/k /oF) * (15oF) = - 0.0143k/k
Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics A.11 Answer:
- a. 1 (Insert); b. 1 (Insert); c. 1 (Insert); d. 3 (No movement)
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 7-17 A.12 Answer:
c.
Reference:
DOE Fundamentals Handbook, Vol. 2, Module 3, p. 15 A.13 Answer:
d.
Reference:
Burn, Introduction to Nuclear Reactor Operations, Section 5.7.10, page 5-33.
SCR1 = S / (1 - K1eff) AND SCR2 = S / (1 - K2eff) 1 = -2.5% K/K 1 = -0.025 K/K K1eff = 1 / (1 - 1)
K1eff = 1 / (1 + 0.025)
K1eff = 0.976; SCR2/SCR1 = S * (1 - 0.976) / S * (1 - K2eff) 7 = 0.024 / (1 - K2eff) 1 - K2eff = 0.0034 K2eff = 1 - 0.0034 K2eff = 0.997 A.14 Answer:
b.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 3-7 A.15 Answer:
a.
Reference:
DOE Fundamentals Handbook, Vol. 2, Module 3, p. 41-42 A.16 Answer:
c.
Reference:
DOE Fundamentals Handbook, Vol. 1, Module 1, p. 61 A.17 Answer:
a.
Reference:
Burn, Introduction to Nuclear Reactor Operations, p. 2-28 A.18 Answer:
d.
Reference:
DOE Fundamentals Handbook, Vol. 2, Module 3, p. 16
(***** END OF CATEGORY A *****)
Category B: Normal/Emergency Operating Procedures and Radiological Controls B.01 Answer:
c.
Reference:
UNM Emergency Plan, 7.3.2 B.02 Answer:
d.
Reference:
UNM Operating Procedures, Section B B.03 Answer:
c.
Reference:
6 Cen = R/hr at 1 ft (6
- 6 Ci) x (0.85
- 0.2) 6.12 R/hr at 1 ft B.04 Answer:
b.
Reference:
UNM Technical Specifications 3.1 and 3.3 B.05 Answer:
c.
Reference:
UNM Emergency Plan B.06 Answer:
a.
Reference:
DR1*(D1)² = DR2*(D2)² 5000 mrem (1)² = 100 mrem (d)² D = 7.07 ft.
B.07 Answer:
d.
Reference:
UNM Training Manual p.26 B.08 Answer:
d.
Reference:
UNM Technical Specifications 4.1, 4.2, and 4.3 B.09 Answer:
a.
Reference:
10 CFR 20.1003 B.10 Answer:
- a. 3; b. 1; c. 4; d. 2
Reference:
10 CFR 20.1003 B.11 Answer:
a.
Reference:
10 CFR 50.54(x) and (y)
B.12 Answer:
c.
Reference:
UNM Technical Specification 3.1, 3.2, 6.1.12
Category B: Normal/Emergency Operating Procedures and Radiological Controls B.13 Answer:
a.
Reference:
UNM Technical Specifications 3.2.d B.14 Answer:
d.
Reference:
UNM Technical Specifications 6.1.8 B.15 Answer:
a.
Reference:
UNM Technical Specifications 6.1.6 B.16 Answer:
- a. 1 (Daily); b. 3 (Annually); c. 2 (Monthly); d. 3 (Annually)
Reference:
UNM Technical Specifications 4.2 UNM Maintenance and Inspection Procedure B.17 Answer:
c.
Reference:
UNM Administrative Procedures (found in Training Manual, p. 16)
B.18 Answer:
b.
Reference:
DR = DR0
- e-t ; T1/2 = 0.693/
DR = DR0
- e-0.693/T1/2 0.9 = 7.5
- e(-0.693)(4)/T1/2 0.12= e-2.772/T1/2 ln(0.12) =ln(e-2.772/T1/2)
-2.12 = -2.772/T1/2 T1/2 = -2.772/-2.12 T1/2 = 1.32 hr
(***** END OF CATEGORY B *****)
Category C: Facility and Radiation Monitoring Systems C.01 Answer:
a.
Reference:
UNM Operating Procedure Section D.5 and UNM SAR p. 9 C.02 Answer:
d.
Reference:
UNM Training Manual, p. 5 C.03 Answer:
b.
Reference:
UNM Training Manual, p. 8 C.04 Answer:
c.
Reference:
UNM Operating Procedures, Start-Up Check-Out C.05 Answer:
c.
Reference:
UNM SAR p. 8 C.06 Answer:
a.
Reference:
Standard NRC question C.07 Answer:
- a. 3 (50 mR/hr); b. 1 (2 mR/hr); c. 4 (100 mR/hr); d. 1 (2 mR/hr)
Reference:
C.08 Answer:
a.
Reference:
UNM SAR p. 8 and Technical Specification 3.1 C.09 Answer:
d.
Reference:
UNM Technical Specification 1.1.16 C.10 Answer:
c.
Reference:
Standard NRC question C.11 Answer:
b.
Reference:
UNM SAR p. 15 C.12 Answer:
d.
Reference:
UNM SAR p. 9 C.13 Answer:
b.
Reference:
UNM Technical Specifications 3.2
Category C: Facility and Radiation Monitoring Systems C.14 Answer:
a.
Reference:
UNM Technical Specifications 3.2 C.15 Answer:
b.
Reference:
UNM SAR p. 12 C.16 Answer:
d.
Reference:
UNM SAR p. 9 C.17 Answer:
d.
Reference:
UNM SAR p. 13 C.18 Answer:
a.
Reference:
UNM SAR p. 9
(***** END OF CATEGORY C *****)
(********** END OF EXAMINATION **********)