ML24255A044

Examination Report Letter No. 50-128/OL-25-01, Texas A&M University

ML24255A044
Person / Time
Site:	05000128
Issue date:	11/15/2024
From:	Travis Tate NRC/NRR/DANU/UNPO
To:	Joel Jenkins Texas A&M Univ
References
50-128/OL-25-01 OL-25-01
Download: ML24255A044 (1)

Text

Jere Jenkins, Director Nuclear Science Center Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, MS 3575 College Station, TX 77843-3575

SUBJECT:

EXAMINATION REPORT NO. 50-128/OL-25-01, TEXAS A&M UNIVERSITY

Dear Jere Jenkins:

During the week of October 21,2024, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your Texas A&M University 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, 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. 50-128

Enclosures:

1. Examination Report No. 50-128/OL-25-01

2. Written examination cc: w/enclosures to GovDelivery Subscribers November 15, 2024 Signed by Tate, Travis on 11/15/24

ML24255A044 NRR-079 OFFICE NRR/DANU/UNPO/CE NRR/DANU/UNPO/OLA NRR/DANU/UNPO/BC NAME ABeasten NJones TTate DATE 11/15/2024 11/15/2024 11/15/2024 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.:

50-128/OL 25-01 FACILITY DOCKET NO.:

50-128 FACILITY LICENSE NO.:

R-83 FACILITY:

Texas A&M University EXAMINATION DATES:

Week of October 21, 2024 SUBMITTED BY:

SUMMARY

During the week of October 21, 2024, the NRC administered operator licensing examinations to four (4) Reactor Operator (RO) candidates, three (3) Senior Reactor Operator-Instant (SRO-I) candidates, and one (1) Senior Reactor Operator-Upgrade (SRO-U) candidate. One SRO-U candidate failed the operating exam. One SRO-I candidate failed Category A of the written examination but passed the operating test. One SRO-I candidate failed Category C of the written examination, was an overall written exam failure, and failed the operating test. The remaining candidates passed all applicable portions of the examinations.

REPORT DETAILS 1.

Examiner:

Amy E. Beasten, PhD, Chief Examiner, NRC 2.

Results:

RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 4/0 1/2 5/2 Operating Tests 4/0 2/2 6/2 Overall 4/0 1/3 5/3 3.

Exit Meeting:

Amy E. Beasten, PhD, NRC Chief Examiner Jere Jenkins, NESC Director Jonathan Grissom, NESC Assistant Director of Operations 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. The NRC examiner discussed some apparent weaknesses among the expected level of knowledge for RO and SRO candidates. Examiner 10/31/2024 Name, Chief Examiner Date observations include: general weakness of the expected level of knowledge concerning the 10 CFR 50.59 process and review authority; surveillance interval requirements; facility staffing requirements, specifically when an SRO is required to be present in the control room and/or directing activities; equipment required for operation; understanding of pulse operations; design and operation of facility ventilation systems, including confinement isolation; control rod design and operation; and Facility Air Monitor design and operation. Additionally, the examiner observed confusion surrounding requirements for nuclear instrumentation channels, including when those instruments are required to be operable. Further, the examiner observed significant delays in identifying and diagnosing out-of-spec conditions during scenarios presented during the exam. At the conclusion of the meeting, the NRC examiner thanked the facility for their support in the administration of the examination.

TEXAS A&M UNIVERSITY Operator Licensing Examination Week of October 21, 2024

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

Texas A&M University REACTOR TYPE:

TRIGA DATE ADMINISTERED:

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 20.00 33.0 A. REACTOR THEORY, THERMODYNAMICS, AND FACILITY OPERATING CHARACTERISTICS 20.00 33.0 B. NORMAL AND EMERGENCY OPERATING PROCEDURES AND RADIOLOGICAL CONTROLS 20.00 33.0 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.

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 _____ (0.25 each)

A06 a b c d ___

A07 a b c d ___

A08 a _____ b _____ c _____ d _____ (0.25 each)

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 ___

B02 a b c d ___

B03 a b c d ___

B04 a b c d ___

B05 a _____ b _____ c _____ d _____ (0.25 each)

B06 a b c d ___

B07 a b c d ___

B08 a _____ b _____ c _____ d _____ (0.50 each)

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 ___

B19 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 _____ (0.33 each)

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

=

+

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

SCR

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

[1.00 point]

Inelastic 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, with the neutron being re-emitted.

c.

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.

d. The process in which a neutron collides with a nucleus causing the nucleus to split into smaller particles.

QUESTION A.02

[1.00 point]

Which ONE of the following statements best describes the infinite multiplication factor, k?

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

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

c.

The ratio of neutrons produced by fission in one generation to the number of thermal neutrons lost through 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.

QUESTION A.03

[1.00 point]

What is the remaining power following the prompt drop in the reactor power when a rod worth of 0.75 K/K is rapidly inserted into a critical reactor? Assume eff = 0.0065

a. 1.50%

b.

6.44%

c.

11.91%

d.

15.12%

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.04

[1.00 point]

A reactor is undermoderated when a/an ______ in the moderator-to-fuel ratio decreases keff because of a/an _________.

a.

increase; decrease in the thermal utilization factor.

b.

increase; increase in resonance absorption.

c.

decrease; increase in the thermal utilization factor.

d.

decrease; increase in resonance absorption.

QUESTION A.05

[1.00 point]

A reactor is shutdown by 4.0% k/k. If control rods are withdrawn until the count rate increases by a factor of 8, and the reactor is still subcritical, what is the new Keff?

a.

0.995 b.

0.992 c.

0.980 d.

0.962 QUESTION A.06

[1.00 point]

Which ONE of the following statements best describes the photoelectric effect?

a.

A gamma interacts with the electric field of a nucleus to create an electron-positron pair.

b.

A gamma interacts with an orbital electron. The entire energy of the gamma is transferred to the electron, which is ejected from its orbit.

c.

A gamma interacts with an orbital electron. Some of the energy of the gamma is transferred to the electron, which is ejected from its orbit. The gamma scatters at a lower energy.

d.

A gamma interacts with an orbital electron and causes ionization by displacing the electron, eventually being captured in the orbital shells of the atom.

QUESTION A.07

[1.00 point]

Which ONE of the following describes when a reactor is critical?

a.

keff = 1; = 0 b.

keff = 0; = 1 c.

keff < 1; > 1 d.

keff > 1; < 1

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.08

[1.00 point, 0.25 each]

For each scenario in Column A, identify the direction in Column B that control rods would need to be moved to maintain constant reactor power. Answers in Column B may be used once, more than once, or not at all.

Column A a.

Buildup of Ar-41 b.

Burnup of U-235 c.

Withdrawal of neutron source d.

Pool water temperature decrease Column B 1.

Insert 2.

Withdrawal 3.

No movement QUESTION A.09

[1.00 point]

Approximately _____ MeV is released instantaneously per fission of U-235.

a.

157 b.

250 c.

190 d.

200 QUESTION A.10

[1.00 point]

The current count rate is 230 cps. An experimenter inserts an experiment into the core and the count rate increases to 500 cps. If the initial Keff was 0.859, what is the worth of the experiment?

a.

+ 0.277 b.

- 0.277 c.

+ 0.095 d.

- 0.095

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.11

[1.00 point]

All of the following statements regarding Xe-135 are true EXCEPT:

a.

Xe-135 is produced directly from fission and is removed from the core by neutron absorption.

b.

After a power increase, Xe-135 concentrations will initially decrease due to increased burnout and will peak at a higher equilibrium value.

c.

After a power decrease, Xe-135 concentrations will initially decrease due to burnout and will peak at a lower equilibrium value.

d.

Following a reactor shutdown, Xe-135 concentrations will increase due to the decay of I-135.

QUESTION A.12

[1.00 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.

The values are highest for the thermal neutron energy range.

c.

It has resonance peaks which expand as fuel temperature increases.

d.

It remains constant for all neutron energies.

QUESTION A.13

[1.00 point]

All of the following factors significantly affect control rod worth EXCEPT:

a.

Nearby control rods b.

Startup source position c.

Fuel burnup d.

Increases in moderator temperature

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.14

[1.00 point]

Which ONE of the following statements best describes the effect of the negative moderator temperature coefficient of reactivity?

a.

Increases in moderator temperature result in a decrease in moderator density, which causes less moderation. As a result, leakage increases and keff decreases.

b.

Increases in moderator temperature result in an increase in moderator density, which causes more moderation. As a result, leakage decreases and keff increases.

c.

Increases in moderator temperature result in a decrease in moderator density, which causes less moderation. As a result, the resonance escape probability decreases and keff increases.

d.

Increases in moderator temperature result in an increase in moderator density, which causes more moderation. As a result, the resonance escape probability increases and keff decreases.

QUESTION A.15

[1.00 point]

For each of the following, replace X with the type of particle (alpha, gamma, neutron, or beta-minus) necessary to complete the reaction. Options may be used once, more than once, or not at all.

a.

82Pb210 83Bi210 + X b.

29Cu65 + X 29Cu66* 30Zn66 + -

c.

92U238 90Th234 + X d.

35Br87 36Kr87 + X QUESTION A.16

[1.00 point]

Which ONE of the following statements best describes the microscopic cross-section ()?

a.

The probability of a given reaction occurring between a neutron and a nucleus, with units of cm2.

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 per unit length of travel of the neutron, with units of cm2.

d.

The probability of a given reaction occurring per unit length of travel of the neutron, with units of cm-1.

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics QUESTION A.17

[1.00 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 spontaneous fission of U-235.

c.

Core neutron population is sustained by the delayed neutron precursors.

d.

In-core nuclear instrumentation lags the prompt drop.

QUESTION A.18

[1.00 point]

All of the following are properties of good reflectors EXCEPT:

a.

Not normally fissionable b.

Low melting point c.

High scattering cross-sections d.

Low absorption cross-sections QUESTION A.19

[1.00 point]

Given a reactor period of 32 seconds, how long will it take for reactor power to quadruple?

a.

11.8 seconds b.

25.2 seconds c.

34.7 seconds d.

44.4 seconds QUESTION A.20

[1.00 point]

Which ONE of the following factors of the six-factor formula is NOT affected by the enrichment of U-235?

a.

Thermal utilization factor b.

Fast non-leakage probability c.

Reproduction factor d.

Resonance escape probability

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

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.01

[1.00 point]

The radiation from an unshielded source is 175 mrem/hr. A 15-mm thick lead sheet is inserted and the radiation level drops to 90 mrem/hr. What is the half-value-layer (HVL) of lead?

a.

2.98 mm b.

8.45 mm c.

15.61 mm d.

47.12 mm QUESTION B.02

[1.00 point]

In accordance with NESC Technical Specifications, a licensed Senior Reactor Operator is required to be present in the control room for which ONE of the following evolutions?

a.

Pulse operation from a reactor power of 300 W.

b.

A planned reactor scram as part of an in-core experiment.

c.

Loading of an experiment with a reactivity worth of -$0.75.

d.

Placement of new fuel in the reactor tank fuel storage racks.

QUESTION B.03

[1.00 point]

In accordance with SOP II-C, Steady State Mode Operation, which ONE of the following conditions could NOT cause the Servo Controller to turn OFF?

a.

Withdrawing Shim Rod 2 to compensate for changes in moderator temperature.

b.

Power level drifts by 2% of the setpoint.

c.

Adjusting the Servo Controller setpoint while in Automatic mode.

d.

The Regulating Rod reaches its full out position.

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.04

[1.00 point]

In accordance with SOP-IX-B, Evacuation Procedures, in the event of an emergency which warrants a facility evacuation, the reactor operator shall perform all of the following actions EXCEPT:

a.

Scram and secure the reactor.

b.

Establish the Emergency Support Center in the control room.

c.

Shutdown building air handling and exhaust systems.

d.

Notify the NRC.

QUESTION B.05

[1.00 point, 0.25 each]

Match the Technical Specification required surveillance activity in Column A to the frequency in Column B. Options in Column B may be used once, more than once, or not at all.

Column A a.

Primary coolant radioactive material content b.

Excess Reactivity measurement c.

Instrumented fuel element calibration d.

Facility Air Monitor system calibration Column B 1.

Weekly 2.

Semiannually 3.

Annually QUESTION B.06

[1.00 point]

In accordance with Technical Specifications, the Reactor Safety Board will review all of the following activities or changes EXCEPT:

a.

A proposal to change the periodicity of the pulse channel calibration from annual to semi-annually.

b.

Introduction of a new procedure governing performance of the thermal power calibration.

c.

Correction of a spelling error on the Startup Checklist procedure.

d.

A proposal to eliminate the procedure for Pulsing Operation so that it may be combined with Steady State Operations procedure.

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.07

[1.00 point]

In accordance with SOP-II-I, Reactor Core Manipulation, which ONE of the following statements regarding control rod configuration for core loading or unloading is true?

a.

No more than 12 fuel bundles in the core unless at least two scrammable control rods and the regulating rod are operable and the neutron source is installed.

b.

No more than 15 fuel bundles in the core unless at least three control rods, including the transient rod, are operable.

c.

No more than 6 fuel bundles in the core unless at least the transient rod and the regulating rods are installed and operable.

d.

No more than 9 fuel bundles in the core unless at least two scrammable control rods are operable and the neutron source is inserted.

QUESTION B.08

[2.00 point, 0.50 each]

Match the term from 10 CFR 20 in Column A with the definition in Column B. Options in Column B may be used once, more than once, or not at all.

Column A a.

Committed Dose Equivalent (CDE) b.

Annual Limit on Intake (ALI) c.

Total Effective Dose Equivalent (TEDE) d.

Derived Air Concentration (DAC)

Column B 1.

Obtained limit for the amount of radioactive material taken into the body of an adult worker by inhalation or ingestion in a year.

2.

The sum of the effective dose equivalent for external exposures and the committed effective dose equivalent for internal exposures.

3.

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.

4.

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.

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.09

[1.00 point]

An alarm on which ONE of the following channels would result in a Notification of Unusual Event declaration?

a.

Channel 6 (Xe-125) b.

Channel 5 (Building particulate) c.

Channel 3 (Stack gas) d.

Channel 2 (Fission gas)

QUESTION B.10

[1.00 point]

In accordance with SOP-II-B, Reactor Startup, all of the following conditions must be met prior to beginning startup EXCEPT:

a.

Temperature thermocouple in Pool Temperature position b.

Reactor mode selector switch in Steady State c.

Reactor Building Area Radiation Monitor alert set to 14 mR/hr and the alarm set to 16 mR/hr d.

Gang switch in neutral QUESTION B.11

[1.00 point]

In accordance with NESC Technical Specifications, all of the following conditions are permissible during reactor operation EXCEPT:

a.

Central exhaust system is creating 0.1 inch of water positive pressure at the sample point.

b.

Pool water temperature is 50 °C.

c.

Pool level is 2.5 feet above reference.

d.

Maximum excess reactivity is 5.0% k/k.

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.12

[1.00 point]

While operating at 900kW, which ONE of the following conditions would be a reportable occurrence, in accordance with Technical Specifications?

a.

Four moveable experiments in the core with reactivity worths of $-1.00.

b.

Running a beam tube experiment with an experiment which off-gasses 10% of its total gas, resulting in personnel exposure of 80% of 10 CFR 20 annual dose limits.

c.

Running the pneumatic transfer system with a rabbit sample containing 2.5mg of TNT equivalent.

d.

Two moveable experiments in the core with reactivity worths of $-1.00 and three secured experiments in the core with reactivity worths of $1.25, $-0.50 and $-1.00.

QUESTION B.13

[1.00 point]

In accordance with the NESC Emergency Plan, for life saving actions during an emergency, the _______ may authorize exposures up to _____s.

a.

Emergency Director; 25 Rem b.

Facility Director; 5 Rem c.

Duty SRO; 5 Rem d.

Senior Radiation Safety Specialist; 25 Rem QUESTION B.14

[1.00 point]

In accordance with SOP-IV-A, Experiment Review and Approval, which ONE of the following individuals may approve a modified routine experiment?

a.

Duty Senior Reactor Operator b.

Reactor Operator c.

Facility Director d.

Senior Health Physicist

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.15

[1.00 point]

What is the dose rate at 1 foot, given 70% of the decay of an 8 Curie source results in emission of a 150 keV gamma?

a.

1.6 R/hr b.

2.52 R/hr c.

3.47 R/hr d.

5.04 R/hr QUESTION B.16

[1.00 point]

In accordance with the NESC Emergency Plan, all of the following individuals may assume the role of Emergency Director EXCEPT:

a.

Director, Nuclear Science Center b.

Senior Reactor Operator on Duty c.

Senior Radiation Safety Specialist d.

Reactor Operator on Duty QUESTION B. 17

[1.00 point]

In accordance with Technical Specifications, all of the following required surveillance activities may be deferred during shutdown EXCEPT:

a.

Primary coolant purity sampling b.

Channel checks of confinement c.

Channel calibration of fuel element temperature channel d.

Shutdown margin determination QUESTION B.18

[1.00 point]

Pursuant to 10 CFR _____, minor deviations from the procedure may be authorized by

______, as long as the deviation does not violate the intent of the procedure, Technical Specifications, or other license requirements.

a.

50.54(y); NSCR Reactor Safety Board b.

50.54(x); Duty SRO c.

50.90; NSCR Reactor Safety Board d.

50.59, Duty SRO

Category B: Normal/Emergency Operating Procedures and Radiological Controls QUESTION B.19

[1.00 point]

An experiment reading 180 mrem/hr was removed from the reactor. Six hours later, it reads 35 mrem/h. What is the half-life of the experiment?

a.

2.53 hr b.

1.42 hr c.

1.27 hr d.

0.98 hr

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

Category C: Facility and Radiation Monitoring Systems QUESTION C.01

[1.00 point]

Which ONE of the following statements best describes the control rod design?

a.

The shim rods and regulating rod are water-followed and the transient rod is air-followed.

b.

The shim rods and regulating rod are fuel-followed and the transient rod is water-followed.

c.

The shim rods are fuel-followed, the regulating rod is water-followed, and the transient rod is air-followed.

d.

All rods are water-followed.

QUESTION C.02

[1.00 point]

In accordance with Technical Specifications, which ONE of the following statements best describes the reason for the requirement that the reactor not be operated if pool level drops below 3 feet from the reference operating level?

a.

This level provides adequate operator response time to a loss of coolant event.

b.

This level ensures the availability of the diffuser system and ensures adequate cooling and shielding for the core.

c.

This level provides an indication to the reactor operator that make-up water should be added to the core.

d.

This level ensures that the departure of nucleate boiling ratio (DNBR) is maintained greater than unity.

QUESTION C.03

[1.00 point]

Which ONE of the following statements best describes what happens when the Fission Product monitor alarms?

a.

Automatic reactor scram b.

Initiates a reactor runback c.

Automatically shuts down the air handling system d.

Alarms in the Radiation Protection office to indicate the filter needs to be changed

Category C: Facility and Radiation Monitoring Systems QUESTION C.04

[1.00 point, 0.33 each]

In accordance with the NESC Safety Analysis Report (SAR), the confinement building has three zones of negative pressure. Match the location in Column A to the negative pressure zone in Column B. Options in Column B may be used once, more than once, or not at all.

Column A a.

Control room b.

Beam ports c.

Upper research level Column B 1.

Maximum negative pressure 2.

Intermediate negative pressure 3.

Least negative pressure QUESTION C.05

[1.00 point]

Which ONE of the following statements best describes the reason for the different zones of negative pressure within confinement?

a.

Areas of maximum negative pressure include areas where contamination is most likely to occur, whereas areas with lesser negative pressures include areas where contamination is less likely to occur, to better mitigate leakage of airborne material to the environment b.

Areas of maximum negative pressure ensure that during normal and emergency conditions, leakage of airborne material is mitigated to essential operations staffing areas, ensuring adequate radiological controls for occupational workers.

c.

Areas of less negative pressure include areas where contamination is most likely to occur, whereas areas with maximum negative pressures include areas where contamination is less likely to occur, to better mitigate leakage of airborne material to the environment d.

Areas of less negative pressure ensure that during normal and emergency conditions, leakage of airborne material is mitigated to essential operations staffing areas, ensuring adequate radiological controls for occupational workers.

QUESTION C.06

[1.00 point]

The log power channel performs all of the following functions EXCEPT:

a.

Period scram b.

Low count rate interlock c.

1 kW interlock d.

Loss of high voltage scram

Category C: Facility and Radiation Monitoring Systems QUESTION C.07

[1.00 point]

Which ONE of the following best describes the how regulating rod height indication is provided in the control room?

a.

A chain-driven digital encoder rotates with the motor and worm assembly to provide carriage height indication in percent.

b.

A chain-driven digital encoder rotates with the lead screw through the acme motor of the drive shaft to provide carriage height indication in percent.

c.

A digital encoder rotates with the lead screw through the electric servo motor of the drive shaft to provide carriage height indication in percent.

d.

A digital encoder rotates with the lead screw through the stepping motor of the drive shaft to provide carriage height indication in percent.

QUESTION C.08

[1.00 point]

The Thermal Column is composed of which of the following materials?

a.

Stainless steel and concrete b.

Stainless steel and aluminum c.

Aluminum and concrete d.

Concrete and boral QUESTION C.09

[1.00 point]

A liquid effluent commonly produced at the facility from normal reactor operation is

_______ which is _______.

a.

Ar-41; produced from irradiation of air bubbles in water b.

Na-24; produced from irradiation of primary coolant piping c.

N-16, produced from irradiation of water d.

H-3; produced from irradiation of water

Category C: Facility and Radiation Monitoring Systems QUESTION C.10

[1.00 point]

Which ONE of the following actions would be considered a Channel CALIBRATION?

a.

Comparison of Wide Range Linear Monitor indications with Safety Power Channel 1 indications of reactor power.

b.

Adjustment of Safety Power Channel 2 indications following performance of the thermal power calibration to correct for acceptable instrument drift.

c.

Verification of correct indication on the Wide Range Linear Monitor by raising reactor power to a known setpoint.

d.

Comparison of current Wide Range Linear Monitor indications with Wide Range Linear Monitor indications at the same reactor power levels during previous operations.

QUESTION C.11

[1.00 point]

Which ONE of the following is NOT a function of the Primary Coolant Cleanup System?

a.

Provide a flow path for makeup water for filling the pool during normal and/or emergency pool fill evolutions.

b.

Maintains water clarity for performance of activities in the pool and observation of submerged equipment.

c.

Provides a filtering mechanism for makeup water.

d.

Maintains pool water purity.

QUESTION C.12

[1.00 point]

Which ONE of the following statements best describes the design of the Log Power Channel?

a.

It is an uncompensated ion chamber filled with BF3 gas.

b.

It is a compensated ion chamber lined with B-10.

c.

It is a liquid scintillation detector filled with U-238.

d.

It is a fission chamber lined with highly enriched U-235.

Category C: Facility and Radiation Monitoring Systems QUESTION C.13

[1.00 point]

Which ONE of the following channels is NOT required for Pulse Mode operation?

a.

High Power level b.

Fuel element temperature c.

Integrated pulse power d.

Manual scram button QUESTION C.14

[1.00 point]

Which ONE of the following statements best describes the function of the Diffuser System?

a.

It mixes the coolant entering the pool with air from the surface which dilutes the concentration of Ar-41 produced.

b.

It creates a turbulent flow of coolant entering the pool, loosening corrosion products that may form during normal operation so that they may be removed by the cleanup system.

c.

It controls the flow of coolant entering the pool for emergency pool fills.

d.

It forces coolant exiting the core deeper into the pool, allowing most of the N-16 to decay before it reaches the surface, thereby lowering radiation levels at the pool surface.

QUESTION C.15

[1.00 point]

Which ONE of the following statements describes the function of the 1 kW interlock?

a.

It ensures that the reactor will shut down following a pulse, even if the transient rod remains withdrawn.

b.

It ensures that the magnitude of the pulse will not cause the Safety Limit to be exceeded.

c.

It ensures that the shim safety and regulating rods cannot be withdrawn during a pulse.

d.

It prevents the reactor power from oscillating during a pulse.

QUESTION C.16

[1.00 point]

In accordance with Technical Specifications, all of the following radiation monitor channels are required to be operable while fuel is being moved EXCEPT:

a.

FAM Channel #2 (Fission Product Monitor) b.

FAM Channel #3 (Stack Gas Monitor) c.

FAM Channel #4 (Building Particulate Monitor) d.

Reactor Bridge Area Radiation Monitor (ARM)

Category C: Facility and Radiation Monitoring Systems QUESTION C.17

[1.00 point]

In accordance with Technical Specification Bases, which ONE of the following statements best describes the reason for limiting pool water temperature below 60 °C?

a.

Operating below this value ensures the resin in the demineralizer tanks will not be degraded.

b.

Operating below this value ensures no damage to facility equipment and components resulting from elevated pool temperatures.

c.

Operating below this value will not risk the fuel temperature exceeding the Limiting Safety System Setting.

d.

Operating below this value will not risk the fuel temperature exceeding the Safety Limit.

QUESTION C.18

[1.00 point]

Which ONE of the following best describes the reason for the high sensitivity of a Geiger-Mueller detector?

a.

A higher voltage is applied to the detector which helps to amplify all incident events b.

Any incident radiation event causing primary ionization results in ionization of the entire detector.

c.

It is lined with special nuclear material which causes high ionization events with low concentrations of incident radiation.

d.

It has a large tube, providing a larger target area to capture all incident events.

QUESTION C.19

[1.00 point]

Which ONE of the following statements correctly describes the interlocks associated with the transient control rod?

a.

Rod Down, Rod Out, Air Applied, Rod Jammed, Low Count Interlock b.

Rod Down, Rod Out, Shim Safety Pulse Interlock, Rod In Override, Low Count Interlock c.

Rod Down, Rod Out, TR Withdrawal, Air Applied, Rod Jammed d.

Rod Down, Rod Out, TR Withdrawal, Air Applied, Low Count Interlock

Category C: Facility and Radiation Monitoring Systems QUESTION C.20

[1.00 point]

In accordance with Technical Specifications, confinement is required for all of the following operations EXCEPT:

a.

Movement of new fuel into the pool storage racks b.

Movement of control rods to support visual inspection surveillance requirement c.

Inserting or removing samples from the irradiation cell d.

Fuel element inspection

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

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

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics A.01 Answer:

c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 2-28 A.02 Answer:

d.

Reference:

DOE Fundamentals Handbook, Vol. 2, Module 3, p. 15 A.03 Answer:

a.

Reference:

P1 P0 =

eff (1 p) eff p P1/P0 = (0.0065 x (1+0.75)) / (0.0065+0.75)

P1/P0 = 0.0150 P1/P0 = 1.50%

A.04 Answer:

d.

Reference:

DOE Fundamentals Handbook, Vol. 2, Module 3, p. 28 A.05 Answer:

a.

Reference:

Burn, Introduction to Nuclear Reactor Operations, Section 5.7.10, page 5-33.

SCR1 = S / (1 - K1eff) AND SCR2 = S / (1 - K2eff) 1 = -4.0% K/K 1 = -0.040 K/K K1eff = 1 / (1 - 1)

K1eff = 1 / (1 + 0.040)

K1eff = 0.9615; SCR2/SCR1 = S * (1 - 0.9615) / S * (1 - K2eff) 8 = 0.0385 / (1 - K2eff) 1 - K2eff = 0.0048 K2eff = 1 - 0.0048 K2eff = 0.995 A.06 Answer:

b.

Reference:

DOE Fundamentals Handbook, Vol. 1, Module 1, p. 67 A.07 Answer:

a.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 3-20 A.08 Answer:

a. 3 (No movement); b. 2 (Withdrawal); c. 3 (No movement); d. 1 (Insertion)

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 7-17

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics A.09 Answer:

d.

Reference:

DOE Fundamentals Handbook, Vol. 1, Module 1, p. 61 A.10 Answer:

c.

Reference:

CR1 / CR2 = (1 - Keff2) / (1 - Keff1) 230 / 500 = (1 - Keff2) / (1 - 0.859) 0.46 * (0.141) = 1 - Keff2 Keff2 = 0.935

= (Keff2 - Keff1) / (Keff2

• Keff1)

= (0.935 - 0.859) / (0.935

• 0.859)

= + 0.095 A.11 Answer:

c.

Reference:

DOE Fundamentals Handbook, Vol. 2, Module 3, p. 41-42 A.12 Answer:

b.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 2-37 A.13 Answer:

b.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 7-19 A.14 Answer:

a.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 3-19 and 6-14 A.15 Answer:

a. -; b. n; c. ; d. -

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 2-60 DOE Fundamentals Handbook, Vol. 1, Module 2, p. 29 A.16 Answer:

a.

Reference:

DOE Fundamentals Handbook, Vol. 1, Module 2, p. 17 A.17 Answer:

c.

Reference:

Burn, Introduction to Nuclear Reactor Operations, p. 3-7 A.18 Answer:

b.

Reference:

DOE Fundamentals Handbook, Vol. 2, Module 4, p. 25

Category A: Reactor Theory, Thermodynamics, and Facility Operating Characteristics A.19 Answer:

d.

Reference:

P = P0et/32 4 = 1et/32 ln(4) = ln(et/32) 1.386 = t/32 T = 44.4 seconds A.20 Answer:

b.

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:

DR = DR0*e-X Find :

90 = 175*e -*15 0.514 = e-*15 ln(0.514) = ln(e-*15)

-0.6655 = -*15

= 0.0444 Insertion of an HVL (thickness of lead), original intensity will be reduced by half.

Find X:

1 = 2* e-0.0444X 0.5 = e-0.0444*X ln(0.5) = ln(e-0.0444*X)

-0.693 = -0.0444*X X= 15.61 mm B.02 Answer:

a.

Reference:

NESC Technical Specifications 6.1.3 B.03 Answer:

b.

Reference:

NESC SOP-II-C, Steady State Mode Operation B.04 Answer:

b.

Reference:

NESC SOP-IX-B, Evacuation Procedures B.05 Answer:

a. 1 (Weekly); b. 3 (Annually); c. 2 (Semiannually); d. 3 (Annually)

Reference:

NESC Technical Specifications 4.1.6, 4.2.2, 4.5, and 4.8.1 B.06 Answer:

c.

Reference:

NESC Technical Specifications 6.2.3 B.07 Answer:

d.

Reference:

NESC SOP-II-I, Reactor Core Manipulation B.08 Answer:

a. 4; b. 1; c. 2; d. 3

Reference:

10 CFR 20.1003 B.09 Answer:

d.

Reference:

NESC SOP-IX-A, Emergency Classification Guide

Category B: Normal/Emergency Operating Procedures and Radiological Controls B.10 Answer:

c.

Reference:

NESC SOP-II-B, Reactor Startup B.11 Answer:

a.

Reference:

NESC Technical Specifications 3.1.6, 3.2.2, 3.3.2, and 3.8.2 B.12 Answer:

b.

Reference:

NESC Technical Specifications 3.6 B.13 Answer:

a.

Reference:

NESC Emergency Plan 3.5 B.14 Answer:

c.

Reference:

NESC SOP-IV-A, Experiment Review and Approval B.15 Answer:

d.

Reference:

6 Cen = R/hr at 1 ft (6

• 8 Ci) x (0.7

• 0.15) 5.04 R/hr at 1 ft B.16 Answer:

c.

Reference:

NESC Emergency Plan, 3.1.1 B.17 Answer:

a.

Reference:

NESC Technical Specifications 4.1.3, 4.2.2, 4.3, 4.8.1 B.18 Answer:

b.

Reference:

10 CFR 50.54(x)

B.19 Answer:

a.

Reference:

DR = DR0, T1 2 =

0.693

DR = DR0 e-.693/T1/2 35 = 180 e-(.693)(6)/T1/2 0.194 = e-(.693)(6)/T1/2 ln(0.481) = ln(e-(.693)(3)/T1/2)

- 1.638 = - 4.158 / T1/2 T1/2 = - 4.158 / - 1.638 T1/2 = 2.53 hr

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

Category C: Facility and Radiation Monitoring Systems C.01 Answer:

c.

Reference:

NESC SAR 4.2 C.02 Answer:

b.

Reference:

NESC Technical Specifications (Bases) 3.8.2 C.03 Answer:

c.

Reference:

NESC SAR 7.7.2 C.04 Answer:

a. Least (3); b. Max (1); c. Intermediate (2)

Reference:

NESC SAR 6.2.1 C.05 Answer:

a.

Reference:

NESC SAR 6.2.1 C.06 Answer:

d.

Reference:

NESC SAR 7.2.3.1 C.07 Answer:

d.

Reference:

NESC SAR 7.3.1.2 C.08 Answer:

b.

Reference:

NESC SAR 10.1.2 C.09 Answer:

c.

Reference:

NESC SAR 11.1.1.2 C.10 Answer:

b.

Reference:

NESC Technical Specification 1.3 C.11 Answer:

b.

Reference:

NESC SAR 5.4.1 C.12 Answer:

d.

Reference:

NESC SAR 7.2.3.1 C.13 Answer:

a.

Reference:

NESC Technical Specification 3.2

Category C: Facility and Radiation Monitoring Systems C.14 Answer:

d.

Reference:

NESC SAR 4.4 C.15 Answer:

b.

Reference:

NESC Technical Specification 3.2.2 C.16 Answer:

a.

Reference:

NESC Technical Specification 3.5.1 C.17 Answer:

c.

Reference:

NESC Technical Specification 3.8.3 C.18 Answer:

b.

Reference:

NRC Standard question C.19 Answer:

d.

Reference:

NESC SAR 7.3.1.1 C.20 Answer:

a.

Reference:

NESC Technical Specification 3.3.1

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

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