ML24052A345

Examination Report Letter No. 50-223/OL-24-01, University of Massachusetts - Lowell

ML24052A345
Person / Time
Site:	University of Lowell
Issue date:	04/25/2024
From:	Travis Tate NRC/NRR/DANU/UNPO
To:	Prosanta Chowdhury Univ of Massachusetts - Lowell
References
50-223/OL-24-01 OL-24-01
Download: ML24052A345 (37)

Text

Dr. Partha Chowdhury, Director Nuclear Radiation Laboratory University of Massachusetts-Lowell One University Avenue Lowell, MA 01854

SUBJECT:

EXAMINATION REPORT NO. 50-223/OL-24-01, UNIVERSITY OF MASSACHUSETTS - LOWELL

Dear Dr. Chowdhury:

During the week of March 4, 2024, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your University of Massachusetts - Lowell Research Reactor. The examinations were 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 Michele DeSouza at 301-415-0747 or via email at Michele.DeSouza@nrc.gov.

Sincerely, Travis L. Tate, 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. 50-223

Enclosures:

1. Examination Report No. 50-223/OL-24-01

2. Written examination cc: w/enclosures to GovDelivery SubscribersApril 25, 2024 Signed by Tate, Travis on 04/25/24

ML24052A345 NRR-079 OFFICE NRR/DANU/UNPO/CE NRR/DANU/UNPO/OLA NRR/DANU/UNPO/BC NAME MDeSouza NJones TTate DATE 4/25/2023 4/25/2023 4/25/2023 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT

REPORT NO.: 50-223/OL-24-01

FACILITY DOCKET NO.: 50-223

FACILITY LICENSE NO.: R-125

FACILITY: University of Massachusetts-Lowell Research Reactor

EXAMINATION DATES: March 05-06, 2024

SUBMITTED BY: ______________________________ 03/13/2024 Michele C DeSouza, Chief Examiner Date

SUMMARY

During the week of March 04, 2024, the NRC administered operator licensing examinations to two Reactor Operator (RO) and one Senior Reactor Operator-Instant (SROI). All candidates passed all applicable portions of the examinations.

REPORT DETAILS

1. Examiners: Michele C DeSouza, Chief Examiner, NRC

2. Results:

RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL

Written 2/0 1/0 3/0 Operating Tests 2/0 1/0 3/0

Overall 2/0 1/0 3/0

3. Exit Meeting:

Michele C DeSouza, Chief Examiner, NRC Leo Bobek, UMLRR, Reactor Supervisor Thomas Regan, UMLRR, Chief, Senior Reactor Operator Tu Cao, UMLRR Training Supervisor

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.

Enclosure 1 University of Massachusetts - Lowell

Operator Licensing Examination

Week of March 4, 2024 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 overall.

12. There is a time limit of three (3) hours for completion of the examination.

U. S. NUCLEAR REGULATORY COMMISSION NON-POWER REACTOR LICENSE EXAMINATION

FACILITY: University of Massachusetts-Lowell

REACTOR TYPE: POOL

DATE ADMINISTERED: March 4, 2024

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 is required to pass the examination. Examinations will be picked up three (3) hours after the examination starts.

% OF CATEGORY % OF CANDIDATE'S CATEGORY VALUE TOTAL SCORE VALUE CATEGORY

20.00 33.3 A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS

20.00 33.3 B. NORMAL AND EMERGENCY OPERATING PROCEDURES AND RADIOLOGICAL CONTROLS

20.00 33.3 C. FACILITY AND RADIATION MONITORING SYSTEMS

60.00 % 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 an overall grade of 70 percent or greater.

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 __________ (0.25 each)

A04 a b c d _____

A05 a __________ b __________ c __________ d __________ (0.25 each)

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 _____

A19 a b c d _____

A20 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 __________ (0.25 each)

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 __________ (0.25 each)

B11 a b c d _____

B12 a b c d _____

B13 a b c d _____

B14 a b c d _____

B15 a __________ b __________ c __________ (0.33 each)

B16 a b c d _____

B17 a b c d _____

B18 a b c d _____

B19 a b c d _____

B20 a b c d _____

(***** END OF CATEGORY B *****)

Category C: Facility 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 _____

C19 a b c d _____

C20 a b c d _____

(***** END OF CATEGORY C *****)

(********** END OF EXAMINATION **********)

EQUATION SHEET

2 0.1sec1 QmcPTmH UAT Pmax 2 eff

t S S

• 4 P P0e SCR 110 sec 1 Keff

eff CR1 1CR22 CR 1K CR 1K SUR 26.06 1 eff1 2 eff2

1 M 1 CR2 P P 10SUR(t)

P P0 1 K CR 0 eff 1

1 Keff1 1 K

• M 1 K SDM eff

eff2 Keff

= + 0.693 K K eff2 eff1 T1 2 K K eff1eff2

Keff1 DR DR et 2 2 K 0 DR1 d1 DR2d2 eff

6CiE n 2 2 DR 2 1 R2 Peak2 Peak1

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 Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.01 [1.0 point]

Which ONE of the following is the definition of Shutdown Margin?

a. The amount of reactivity available above what is required to keep the reactor critical.

b. The amount of reactivity that would be added to a core if the rods in critical cold clean reactor were fully inserted.

c. Provides a measure of excess reactivity available to overcome fission product buildup, fuel burnup, and power defect.

d. The negative reactivity inserted by an increase in moderator temperature within the core where the reactor is brought from zero to full power.

QUESTION A.02 [1.0 point]

Given a reactor period of 16.00 seconds, how long will it take for reactor power to quadruple?

a. 17.88

b. 20.06

c. 22.18

d. 31.63

QUESTION A.03 [1.0 point, 0.25 each]

Match the isotope in Column A with the type of material in Column B. Options in Column B may be used once, more than once, or not at all.

Column A Column B

a.Thorium-232 1. Fissile

b.Uranium-233 2. Fertile

c.Plutonium-240 3. Fissionable

d. Plutonium-239 Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.04 [1.0 point]

The reactor is scrammed from 250 kW. After an initial power drop to 25 kW, the power level is decreasing at a constant period. What is the reactor power seven minutes later?

a. 22.9 kW

b. 14.8 kW

c. 4.91 kW

d. 1.31 kW

QUESTION A.05 [1.0 point, 0.25 each]

Replace X with the type of decay necessary (Alpha, Beta, Gamma or Neutron emission) to produce the following reactions. Choices may be used once, more than once, or not at all.

a. 92U238 90Th234 + X

b. 83Bi203 82Pb203 + X

c. 2He4 + 4Be9 6C12 + X

d. 84Po210 82Pb206 + X

QUESTION A.06 [1.0 point]

Which ONE of the following statements is NOT a result of increases in moderator temperature during reactor operation?

a. Rod worth decreases

b. Thermal utilization factor increases

c. Thermal non-leakage probability increases

d. Resonance escape probability decreases Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.07 [1.0 point]

A reactor is slightly supercritical (k=1.001) with a thermal utilization factor of 0.898. A control rod is inserted to bring the reactor back to critical. Assuming all other factors remain unchanged, what is the new value for the thermal utilization factor?

a. 0.758

b. 0.794

c. 0.814

d. 0.897

QUESTION A.08 [1.0 point]

Which ONE of the following describes Integral Rod Worth?

a. The reactivity change per unit movement of a rod.

b. The control rod worth when inserted at maximum reactor flux.

c. The total reactivity worth of the rod at a particular position of withdrawal.

d. The plot of the slope of the change in reactivity over the change in rod position (/x).

QUESTION A.09 [1.0 point]

A fast neutron will lose the most energy in a collision with which ONE of the following atoms?

a. H1

b. H2

c. C12

d. U238 Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.10 [1.0 point]

Which ONE of the following describes the difference between prompt and delayed neutrons?

a. Prompt neutrons are produced from spontaneous fission of U-235 in the fuel, and delayed neutrons are the result of fission in U-238.

b. Prompt neutrons are produced immediately and directly from the fission event and delayed neutrons are produced immediately following the first beta decay of fission fragments.

c. Prompt neutrons are responsible for the ability to control the rate at which power can rise in the reactor and delayed neutrons are responsible for the rate at which a reactor can be shut down.

d. Prompt neutrons ensure there is a sufficient neutron population to overcome the effects of fission product poisoning following a shutdown and delayed neutrons are responsible for lengthening the neutron generation time to ensure the reactor does not go prompt critical.

QUESTION A.11 [1.0 point]

Which ONE of the following is the definition of Thermal Utilization Factor?

a. The ratio of the number of fast neutrons absorbed in fuel to the number of fast neutrons absorbed in the reactor material.

b. The ratio of the number of fast neutrons produced by thermal fission to the number of thermal neutrons absorbed in the fuel.

c. The ratio of the number of thermal neutrons absorbed in fuel to the number of thermal neutrons absorbed in the reactor material.

d. The ratio of the number of fast neutrons produced by thermal fission to the number of thermal neutrons absorbed in the fuel.

QUESTION A.12 [1.0 point]

Which ONE of the following terms is matches with the definition the product of number density and microscopic cross section of an element?

a. Decay constant

b. Mean free path

c. Macroscopic cross section

d. Thermal cross section Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.13 [1.0 point]

Which ONE of the following answers is the correct number of protons, the number of neutrons, and the number of electrons in the Uranium-238 nucleus (92U238)?

a.92, 92, 143

b.92, 143, 146

c.92, 146, 92

d.146, 143, 92

QUESTION A.14 [1.0 point]

A subcritical reactor has a keff of 0.719. How much reactivity is added to change the keff to 0.941?

a. 0.117 k/k

b. 0.242 k/k

c. 0.328 k/k

d. 0.543 k/k

QUESTION A.15 [1.0 point]

Which ONE of the following best describes the effective multiplication factor, keff?

a. The ratio of the number of total neutrons produced by fission in one generation to the number of neutrons lost through leakage and absorption in the preceding generation.

b. The ratio of the number of fast neutrons produced by fission in one generation to the number of fast neutrons lost through leakage and absorption in the preceding generation.

c. The ratio of the number of thermal neutrons produced by fission in one generation to the number of thermal neutrons lost through leakage and absorption in the preceding generation.

d. The ratio of the number of total 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.16 [1.0 point]

Which ONE of the following materials has a primary purpose of thermalizing neutrons?

a. Absorber

b. Reflector

c. Deflector

d. Moderator

QUESTION A.17 [1.0 point]

A reactor contains a neutron source of 1275 neutrons/second. If the stable total neutron production rate is 5650 neutrons/second, what is the value of keff?

a. 0.696

b. 0.744

c. 0.805

d. 0.958

QUESTION A.18 [1.0 point]

Which ONE of the following best describes inelastic scattering?

a. A neutron interacts with a target nucleus and momentum and kinetic energy are conserved.

b. A neutron is absorbed by the target nucleus to form a compound nucleus, which emits a neutron with lower kinetic energy, and the resulting excited state nucleus emits a gamma.

c. A neutron is absorbed by the target nucleus to form a compound nucleus, which releases its excitation energy by emitting a gamma ray.

d. A neutron is absorbed by the target nucleus to form a compound nucleus, which ejects an alpha particle or proton.

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

QUESTION A.19 [1.0 point]

Which ONE of the following parameters is MOST significant in determining the differential rod worth of a control rod?

a. Rod speed

b. Flux shape

c. Reactor power

d. Fuel Temperature

QUESTION A.20 [1.0 point]

Which ONE of the following defines eff?

a. The fraction of all fission neutrons born as delayed neutrons.

b. The fraction of neutrons at fast energies born as delayed neutrons.

c. The fraction of neutrons at thermal energies born as delayed neutrons.

d. The average of the total delayed neutron fractions of the different types of fuel.

(***** END OF CATEGORY A *****)

Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.01 [1.0 point, 0.25 each]

Match the conditions or events in Column A to the appropriate UMLRR emergency Class in Column B. Options in Column B may be used once, more than once, or not at all.

Column A Column B

a. Personnel injury

1. Non-reactor related safety event

b. Individual contamination

2. Notification of unusual event

c. Credible security event impacting reactor building 3. Alert

d. Fire affecting reactor 4. Site Area Emergency

QUESTION B.02 [1.0 point]

Which ONE of the following is NOT allowed as an experiment in the reactor under any circumstances?

a. Fueled experiment that yields 500 microcuries Iodine-133.

b. 15 milligrams of explosive TNT.

c. The reactivity worth of a movable experiment is 0.28% k/k.

d. The reactivity worth of all movable experiments is 0.4% k/k.

QUESTION B.03 [1.0 point]

Which ONE of the following regulations states the UMLRR Requalification Program must be conducted for a continuous period not to exceed 24 months?

a. 10 CFR 19

b. 10 CFR 20

c. 10 CFR 50

d. 10 CFR 55 Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.04 [1.0 point]

Which ONE of the following measuring channels is required to operate only in FORCED CONVECTION mode of operation, in accordance with UMLRR Technical Specifications ?

a. Log N (Period)

b. Power level (Linear N)

c. Reactor pool temperature

d. Reactor coolant flow rate

QUESTION B.05 [1.0 point]

In accordance with 10 CFR 20, which ONE of the following correctly defines the total effective dose equivalent (TEDE)?

a. The sum of the products of the weighting factors applicable to each of the body organs or tissues that are irradiated and the committed dose equivalent to these organs or tissues.

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 an intake of one ALI.

d. The sum of the products of the dose equivalent to the organ or tissue and the weighting factors applicable to each of the body organs or tissues that are irradiated.

QUESTION B.06 [1.0 point]

All of the following are Technical Specifications requirements EXCEPT which ONE of the below?

a. Reactor pool temperature shall be at or less than 108°F.

b. pool water shall be at or above 24.25 feet of water above reactor core during operations.

c. The pool water conductivity shall be < or = 5 mho/cm.

d. The excess reactivity shall be > 4.7% k/k.

Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.07 [1.0 point]

Which ONE of the following is the greatest immediate concern in the event of a significant loss of reactor pool water due to a rupture of the pool wall?

a. Cladding rupture resulting in a fission product release.

b. Groundwater contamination to the surrounding water table.

c. Increased personnel exposure due to higher amounts of radiation.

d. Zirconium Hydride interaction with oxygen in air, releasing explosive hydrogen gas due to the TRIGA fuel overheating.

QUESTION B.08 [1.0 point]

A sample reads 456 mrem/hr at a distance of 3 feet from the source. How far away from the source will the reading be 10 mrem/hr?

a. 17 feet

b. 20 feet

c. 34 feet

d. 65 feet

QUESTION B.09 [1.0 point]

An experiment reading 82.00 mrem/hr was removed from the reactor. Four hours later, it reads 8.00 mrem/h. What is the half-life of the radioisotope in the experiment sample?

a. 1.01 hr

b. 1.19 hr

c. 1.55 hr

d. 2.12 hr

QUESTION B.10 [1.0 point, 0.25 each]

For each ONE of the following, identify the required surveillance frequency as DAILY, QUARTERLY, ANNUALLY, BIENNIALLY. Answers may be used once, more than once, or not at all.

a. Primary coolant flow rate

b. Emergency exhaust system operability

c. Carbon filter efficiency

d. Manual scram (channel test)

Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.11 [1.0 point]

Which ONE of the following is NOT in the line of succession for Emergency Director, in accordance with UMLRR Emergency Plan?

a. Most Senior SRO

b. Reactor Supervisor

c. Radiation Laboratory Director

d. Fire Chief, City of Lowell

QUESTION B.12 [1.0 point]

10 CFR Part ________ requires all applicants for a reactor operator or senior reactor operator license to submit NRC Form 396 and 398 to the US NRC before taking the examination.

a. 19

b. 20

c. 50

d. 55

QUESTION B.13 [1.0 point]

UMLRR emergency plan accident scenarios shall include all the following EXCEPT which ONE of the following.

a. Medical emergency drills involving a simulated contaminated individual.

b. Radiological monitoring including contamination control methods, dose rate measurements, nonessential personnel evacuation, and record keeping.

c. Communication drills designed to ensure reliability of the system(s) and correct transmission and receipt of messages.

d. Submission and approval thru the Nuclear Regulatory Commission prior to implementation.

QUESTION B.14 [1.0 point]

Which ONE of the following is classified as a Protective Action?

a. Actions to correct and terminate an emergency.

b. Actions taken after an emergency to restore the facility to its pre-emergency condition.

c. Actions taken during or after an emergency to obtain and process information which is necessary to make decisions to implement specific emergency procedures.

d. Actions taken in anticipation of or after an emergency has occurred to protect public health and safety of individuals and to prevent damage to property.

Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.15 [1.0 point, 0.33 each]

Match the Emergency Terms in Column A to the Emergency Definitions in Column B, according to the UMLRR Emergency Plan.

Column A 1.Actions measures taken to

a. Assessment Actions correct and terminate an emergency.

b. Corrective Actions

c. Recovery Actions 2. Actions taken after the emergency to restore the facility to its pre-emergency condition.

3. Actions taken during or after an emergency to obtain and process information necessary to implement specific emergency procedures.

Column B

QUESTION B.16 [1.0 point]

Which ONE of the following events does NOT require the direction of a licensed Senior Reactor Operator at the facility?

a. Recovery from an unscheduled shutdown

b. Initial reactor startup and approach to power

c. Relocation of control rods within the reactor core

d. Insertion of a movable experiment with a worth of 0.1% k/k

QUESTION B.17 [1.0 point]

Which ONE of the following is the MINIMUM number of required radiation monitoring systems to be classified as operable in accordance with UMLRR Technical Specifications?

a. 1 Area Radiation Monitor (ARM) and 1 Continuous Air Monitor (CAM)(3rd floor)

b. 1 ARM (pool), 1 ARM (1st floor), and 1 stack particulate

c. 1 ARM (pool), 1 ARM (1st floor), and 1 CAM

d. 1 ARM (pool), 1 ARM (1st floor), 1 CAM (3rd floor), 1 stack particulate and 1 stack gaseous Category B: Normal/Emergency Operating Procedures and Radiological Controls

QUESTION B.18 [1.0 point]

Which ONE of the following is the appropriate 10 CFR 55 requirement that is associated with a time interval of one year?

a. Operating Test

b. Written Examination

c. License Expiration

d. Medical Examination

QUESTION B.19 [1.0 point]

Which ONE of the following changes must be submitted to NRC for approval prior to implementation?

a. Remove a definition of Channel Test listed in the UMLRR Technical Specifications.

b. Replace a primary coolant pump with an identical pump.

c. Add new limitation to the Pre-Startup Checklist Procedure.

d. Add more responsibilities to the Radiation Safety Officer listed in the radiation safety procedure.

QUESTION B.20 [1.0 point]

Assume you are currently a licensed operator at UMLRR reactor. Which ONE of the following is a requirement of 10 CFR 55, Operators Licenses?

a. All licensed operators must pass an annual written requalification exam.

b. All licensed operators must successfully complete a continuous requalification program, not to exceed 24 months.

c. All licensed operators must actively perform the functions of an operator or senior operator for a minimum of 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> per quarter to maintain active status.

d. All licensed operators must have a medical examination by a physician every 3 years.

(***** END OF CATEGORY B *****)

Category C: Facility and Radiation Monitoring Systems

QUESTION C.01 [1.0 point]

Which ONE of the following is the purpose of the dash pots on the control rods?

a. Force air to allow pulsing

b. Slow the rod down to prevent damage

c. Draw water in to support slowing neutrons

d. Create a suction effect to move the rod down quickly

QUESTION C.02 [1.0 point]

Which ONE of the following detectors provides reactor period?

a. Fission Chamber

b. Boron-10 Proportional Counter

c. Uncompensated Ion Chamber

d. Compensated Ion Chamber

QUESTION C.03 [1.0 point]

Which ONE of the following will result from the inadvertent > 1 inch movement of the reactor bridge?

a. Rod rundown

b. Evacuation alarm

c. Automatic scram

d. Status light illumination on the reactor control console only

QUESTION C.04 [1.0 point]

Which ONE of the following is the gaseous radioactive waste product produced in largest quantity at the UMLRR?

a. Argon-41

b. Helium-2

c. Radon-222

d. Nitrogen-16 Category C: Facility and Radiation Monitoring Systems

QUESTION C.05 [1.0 point]

Which ONE of the following best describes the difference between a Potential Local Radiation Emergency Alarm (P-LREA) and a Potential General Radiation Emergency Alarm (P-GREA)?

a. The P-LREA requires manual operator action to isolate containment and a reactor scram, where the P-GREA automatically initiates both those functions.

b. The P-GREA requires manual operator response to isolate containment and a reactor scram, where the P-LREA automatically initiates both those functions.

c. The P-LREA requires manual operator action to isolate containment, whereas the P-GREA automatically initiates a containment isolation signal.

d. The P-GREA requires manual operator action to isolate containment, whereas the P-LREA automatically initiates a containment isolation signal.

QUESTION C.06 [1.0 point]

Which ONE of the following is the neutron poison material in the control elements?

a. B4C2 in the regulating rod

b. Boron in the safety blades

2C in all but the regulating blade c. B

d. B4C in the safety blades and regulating rod

QUESTION C.07 [1.0 point]

If there is a significant buildup of radioactivity from the reactor pool, what is the impact on the pool water conductivity?

a. Increases

b. Decreases

c. Stays the same

d. No relationship between radioactivity and conductivity in the pool water Category C: Facility and Radiation Monitoring Systems

QUESTION C.08 [1.0 point]

According to the UMLRR Technical Specifications, the standard fuel element shall be flat plate MTR-type elements. The standard fuel element shall contain:

a. Uranium Silicide (U3Si2), enriched to less than 20% U-235, in 16 aluminum clad fueled plates with 2 outer unfueled plates

b. Uranium Dioxide (UO2), enriched to less than 20% U-235, in 16 aluminum clad fueled plates with 2 outer unfueled plates

c. Uranium Silicide (U3Si2), enriched to less than 20% U-235, in 18 aluminum clad fueled plates with 2 outer unfueled plates

d. Uranium Dioxide (UO2), enriched to less than 20% U-235, in 18 aluminum clad fueled plates with 2 outer unfueled plates

QUESTION C.09 [1.0 point]

Which ONE of the following ventilation valves FAIL OPEN on a loss of service air?

a. Main Intake Valve (Valve A)

b. Stack Isolation Valve (Valve C)

c. Facilities Exhaust Valve (Valve E)

d. Ventilation Supply Bypass/Cross-over Valve (Valve F)

QUESTION C.10 [1.0 point]

Which ONE of the following conditions would prevent the reactor operator from switching to auto control mode?

a. Reactor power at 875 kW

b. Power schedule set at 900 kW

c. Reactor Period at 20 seconds

d. Primary Coolant Flow Rate at 1600 gpm Category C: Facility and Radiation Monitoring Systems

QUESTION C.11 [1.0 point]

Which ONE of the following is the neutron absorbing element in the servo-regulating rod?

a. Boron

b. Hafnium

c. Cadmium

d. Aluminum

QUESTION C.12 [1.0 point]

Which ONE of the following indicates the cleanest pool water?

a. Lowest pH

b. Highest pH

c. Highest resistivity

d. Highest conductivity

QUESTION C.13 [1.0 point]

All fuel elements shall be stored in a geometrical array where the keff is less than ________ for all conditions of moderation.

a. 0.8

b. 0.9

c. 1.0

d. 1.1

QUESTION C.14 [1.0 point]

A neutron flux will activate isotopes in air. The primary isotope of concern is:

a. Kr80 (Kr79 (n, ) Kr 80)

b. Ar41 (Ar40 (n, ) Ar 41)

c. N16 (O16 (n,p) N16)

d. H2 (H1 (n, ) H 2)

Category C: Facility and Radiation Monitoring Systems

QUESTION C.15 [1.0 point]

In which region of the output signal versus applied voltage curve does a fission chamber operate?

a. Ion Chamber

b. Proportional

c. Geiger-Mueller

d. Limited Proportional

QUESTION C.16 [1.0 point]

Which ONE of the following combinations of detector alarms would warrant the reactor operator activating the Limited Radiation Emergency Alarm?

a. Fission Product Monitor (E) and Core Exit Lane (S)

b. Stack Monitor (A) and Building Exhaust Plenum (I)

c. Reactor Constant Air Monitor (C) and Control Room (R)

d. Reactor Constant Air Monitor (D) and Bridge (K)

QUESTION C.17 [1.0 point]

During a reactor startup, control blades are withdrawn from the core. Which ONE of the following conditions will cause a reactor scram?

a. Startup count rate drops below 3 cps

b. Primary Coolant Flow at 1250 gpm

c. Reactor Period <15 seconds

d. Master Switch to ON 10-second alarm

QUESTION C.18 [1.0 point]

What is the maximum time is allowed for control blades to reach the fully inserted position on a reactor scram?

a. 0.5 seconds

b. 1.0 second

c. 1.5 seconds

d. 2.0 seconds Category C: Facility and Radiation Monitoring Systems

QUESTION C.19 [1.0 point]

During reactor operation, the emergency exhaust system is in automatic mode. Which ONE of the following would cause Fan EF-14 to start and Emergency Exhaust Valve D to open?

a. Differential pressure drops to negative 0.50 +/- 0.05 inch water column

b. Differential pressure drops to negative 0.25 +/- 0.05 inch water column

c. Differential pressure rises to positive 0.25 +/- 0.05 inch water column

d. Differential pressure rises to positive 0.50 +/- 0.05 inch water column

QUESTION C.20 [1.0 point]

Reactor is in operation. Using the drawing of the primary system provided below, which ONE of the following correctly describes the reactor status if the valve P-12 is opened?

a. Rod Rundown

b. Reactor scram

c. Rod Withdrawal Prohibit

d. Nothing changes, no impact

(***** END OF CATEGORY C *****)

(******** END OF EXAMINATION ********)

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

A.01 Answer: b.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 3.3.7, p. 3-31 and problem 3.4.4, p. 3-33

A.02 Answer: c.

Reference:

P = P0 et/T 4 = 1t/16s ln(4) = ln(t/16s) 1.386 = t/16s t = (1.386)*16s t = 22.18 seconds

A.03 Answer: a. (2) fertile; b. (1) fissile; c. (3) fissionable; d. (1) fissile

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 1, p. 50-52

A.04 Answer: d.

Reference:

P = P0 e-t/T P = 250 kW

• e(420s/-80s) 250 kW

• e-5.25 250 kW

• 0.0052475; P = 1.31 kW = 1310 watts

A.05 Answer: a. alpha b. Beta (+1 0) c. neutron d. alpha

Reference:

NRC standard question

A.06 Answer: a.

Reference:

Burn, Introduction to Nuclear Reactor Operation, Section 3.3.2, p. 3-16

A.07 Answer: d.

Reference:

k=1.001; critical, k=1.000; 0.898 x 1.000//1.001 = 0.897

A.08 Answer: c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 3.4, p. 3-32 & UC-Irvine Chapter 6.4.1, Figure 6.6

A.09 Answer: a.

Reference:

NRC standard question Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

A.10 Answer: b.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 1, p. 29

A.11 Answer: c.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 2, Module 3, p. 4

A.12 Answer: c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 2.5.2, p. 2-43

A.13 Answer: c.

Reference:

Chart of Nuclides; 92 protons, 146 neutrons, 92 electrons

A.14 Answer: c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 3.3.4, p 3-20-21

= (k eff2-keff1)/(keff1*keff2)

= (0.941-0.719) / (0.719*0.941); 0.222 / 0.677

= 0.328 k/k

Answer: a.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 2,

p. 15

A.16 Answer: d.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 1, Module 2, p. 23

A.17 Answer: b.

Reference:

Source CR = (S) / (1 - keff)

(1275) / (1 - keff) = 5650; 1275 / 5650 = (1 - keff) keff = 0.774 DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 2, Module 4, p. 4

A.18 Answer: b.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory, Volume 1,

p. 47

A.19 Answer: b.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 7, p. 7-4 Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics

A.20 Answer: c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Volume 2, Section 3.2.4

(***** END OF CATEGORY A *****)

Category B: Normal/Emergency Operating Procedures and Radiological Controls

B.01 Answer: a. 1-Non-reactor safety related event; b. 1-Non-reactor safety related event; c.

2-Notification of Unusual Event; d. 3-Alert

Reference:

UMLRR Emergency Plan, Table II

B.02 Answer: c.

Reference:

UMLRR Technical Specifications 3.7.1 & 3.7.2

B.03 Answer: d.

Reference:

10 CFR 55.59(a)(1)

B.04 Answer: d.

Reference:

UMLRR Technical Specifications 3.2

B.05 Answer: b.

Reference:

10 CFR 20.1003

B.06 Answer: d.

Reference:

UMLRR Technical Specifications 2.2.2, 3.1.1, and 3.3

B.07 Answer: c.

Reference:

NRC standard question

B.08 Answer: b.

Reference:

DR1*(D1)2 = DR2*(D2)2 ;

456 mrem*(3)2 = 10 mrem(d)2; 4104/10 = d2 = 410.4 d = 20.26 feet

B.09 Answer: b.

Reference:

DR=DR0e(-t) T1/2=0.693/

DR = DR0 e-.693/T1/2 8 = 82 e-(.693)(4)/T1/2 0.0923 = e-(2.772)/T1/2 ln(0.0976) = ln(e-(2.772)/T1/2)

-2.327 = -2.772 / T1/2 T1/2 = -2.772 / -2.327 T1/2 = 1.19 hr

B.10 Answer: a. Annually; b. Quarterly; c. Biennially; d. Daily

Reference:

UMLRR Technical Specifications 4.2.3 & 4.5 Category B: Normal/Emergency Operating Procedures and Radiological Controls

B.11 Answer: d.

Reference:

UMLRR Emergency Plan, Table I and 3.1.10

B.12 Answer: d.

Reference:

10 CFR Part 55

B.13 Answer: d.

Reference:

UMLRR Emergency Plan, Section 10.1

B.14 Answer: d.

Reference:

UMLRR Emergency Plan, Section 2.1.7

B.15 Answer: a. 3; b. 1; c. 2

Reference:

UMLRR Emergency Plan, 2.15, 2.16, & 2.19

B.16 Answer: d.

Reference:

UMLRR Technical Specifications 3.7 & 6.1.3

B.17 Answer: d.

Reference:

UMLRR Technical Specifications 3.6.1

B.18 Answer: a.

Reference:

10 CFR 55

B.19 Answer: a.

Reference:

10 CFR 50.59 & 10 CFR 50.90

B.20 Answer: b.

Reference:

10 CFR Part 55

(***** END OF CATEGORY B *****)

C.01 Answer: b.

Reference:

UMLRR SAR 3.5.2

C.02 Answer: d.

Reference:

UMLRR SAR Part 1, 7.4.1.2

C.03 Answer: c.

Reference:

UMLRR SAR Part 2, 3.2.3

C.04 Answer: a.

Reference:

UMLRR Technical Specifications 3.6.2

C.05 Answer: c.

Reference:

UMLRR SAR 7.7.5

C.06 Answer: d.

Reference:

UMLRR SAR 4.5

C.07 Answer: a.

Reference:

UMLRR Technical Specifications 4.5

C.08 Answer: a.

Reference:

UMLRR Technical Specifications 5.1

C.09 Answer: d.

Reference:

UMLRR SAR 3.4.2.2

C.10 Answer: c.

Reference:

UMLRR SAR 4.4.12

C.11 Answer: a.

Reference:

UMLRR SAR 4.1.6

C.12

Enclosure 1 Category B: Normal/Emergency Operating Procedures and Radiological Controls

Answer: c.

Reference:

NRC standard question

C.13 Answer: b.

Reference:

UMLRR Technical Specifications 5.4

C.14 Answer: b.

Reference:

UMLRR SAR 7.1.2

C.15 Answer: b.

Reference:

NRC standard question

C.16 Answer: a.

Reference:

UMLRR SAR, Appendix 10

C.17 Answer: b.

Reference:

UMLRR Technical Specifications 3.2, Table I

C.18 Answer: b.

Reference:

UMLRR Technical Specifications 3.1.4

C.19 Answer: c.

Reference:

UMLRR SAR 3.4.2.2

C.20 Answer: b.

Reference:

UMLRR SAR 4.2.2.4

(***** END OF CATEGORY C *****)

(******** END OF EXAMINATION ********)