Text

Examination Report No. 50-128/OL-18-01, Texas A&M University
	ML17331B447
Person / Time
Site:	05000128
Issue date:	01/10/2018
From:	Anthony Mendiola; Research and Test Reactors Oversight Projects Branch
To:	Mcdeavitt S; Texas A&M Univ
	Michele DeSouza
References
	50-128/18-01 50-128/OL-18-01
	Download: ML17331B447 (35)
	v • d • e

January 10, 2018 Dr. Sean McDeavitt, Director Nuclear Science Center Texas A&M University 1095 Nuclear Science Road College Station, TX 77843

SUBJECT:

EXAMINATION REPORT NO. 50-128/OL-18-01, TEXAS A&M UNIVERSITY

Dear Dr. McDeavitt:

During the week of November 6, 2017, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your Texas A&M University Nuclear Science Center (NSC) 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 (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site 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 Ms. Michele DeSouza at (301) 415-0747 or via e-mail at Michele.DeSouza@nrc.gov.

Sincerely,

/RA/

Anthony J. Mendiola, Chief Research and Test Reactors Oversight Branch Division of Licensing Projects Office of Nuclear Reactor Regulation Docket No. 50-128

Enclosures:

1. Examination Report No. 50-128/OL-18-01

2. Written Examination cc: w/o enclosures: See next page

ML17331B447 NRR-079 OFFICE NRR/DLP/PROB:CE NRR/DIRS/IOLB:LA NRR/DLP/PROB:BC NAME MDeSouza ABaxter AMendiola DATE 11/27/2017 11/27/2017 01/10/2018

Texas A&M University Docket No. 50-128 cc:

Mayor, City of College Station P.O. Box Drawer 9960 College Station, TX 77840-3575 Governors Budget and Policy Office PO Box 12428 Austin, Texas 78711-2428 Dr. Dimitris C. Lagoudas, Deputy Director Texas A&M University System Texas A&M Engineering Experiment Station 241 Zachry Engineering Center College Station, Texas 77843 Mr. Jerry Newhouse, Assistant Director Nuclear Science Center Texas A&M University Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, MS 3575 College Station, Texas 77843 Radiation Program Officer Bureau of Radiation Control Dept. Of State Health Services Division for Regulatory Services 1100 West 49th Street, MC 2828 Austin, TX 78756-3189 Technical Advisor Office of Permitting, Remediation &

Registration Texas Commission on Environmental Quality P.O. Box 13087, MS 122 Austin, TX 78711-3087 Test, Research and Training Reactor Newsletter P.O. Box 118300 University of Florida Gainesville, FL 32611 Mr. Scott Miller, Manager Reactor Operations Texas A&M University Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, MS 3575 College Station, Texas 77843 State Energy Conservation Office Comptroller of Public Accounts P.O. Box 13528 Austin, TX 78711-3528 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.:

50-128/OL-18-01 FACILITY DOCKET NO.:

50-128 FACILITY LICENSE NO.:

R-83 FACILITY:

Texas A & M NSC EXAMINATION DATES:

November 6-10, 2017 SUBMITTED BY:

____/RA/ ________________

__01/10/2018__

Michele DeSouza, Chief Examiner Date

SUMMARY

During the week of November 6, 2017, the NRC administered an operator licensing examination to two Senior Reactor Operator Upgrade (SRO-U) candidates, one Senior Reactor Operator Instant (SRO-I), and two Reactor Operator (RO) candidates. The candidates passed all applicable portions of the examinations.

REPORT DETAILS

1.

Examiner:

Michele 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 3/0 5/0 Overall 2/0 3/0 5/0

3.

Exit Meeting:

Michele C. DeSouza, Chief Examiner, NRC Jerry Newhouse, Associate Director, TXA&M NSC Scott Miller, Manager, Reactor Operations, TXA&M NSC Cameron Macdonald, Reactor Supervisor, TXA&M NSC Per discussion with the facility, prior to administration of the examination, adjustments were accepted. Upon completion of the examination, the NRC Examiner met with facility staff representatives to discuss the results. Based on candidate responses, the NRC recommended the facility emphasize utilization to TXA&M Standard Operating Procedures as appropriate. At the conclusion of the meeting, the NRC examiner thanked the facility for their support in the administration of the examination.

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

TX A&M NSC REACTOR TYPE:

TRIGA DATE ADMINISTERED:

11/09/2017 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

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 ___ (0.25 each)

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 ___

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 ___

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 ___

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 ___ (0.25 each)

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 ___ (0.50 each)

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

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

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.

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

=

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P 0

eff K

S S

SCR

=

1

sec 10 1

4

x

=

+

=

eff SUR 06 26

(

)

(

)

2 1

1 1

2 1

eff eff K

CR K

CR

=

(

)

(

)

2 2

1 1

=

CR CR 2

1 1

1 eff eff K

K M

=

1 2

1 1

CR CR K

M eff

=

)

(

0 10 t

SUR P

P=

(

)

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P P

=

eff eff K

K SDM

=1

=

+

=

eff 2

1 1

2 eff eff eff eff K

K K

K

=

693

.0 2

1 =

T eff eff K

K 1

=

t e

DR DR

=

0

( )

2 6

R n

E Ci DR=

2 2

1 1

d DR d

DR

=

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2 2

Peak Peak

=

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Q P

=

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.01

[1.0 point]

What is the reason the stable negative period following a scram is always the same value (- 80 second) regardless of initial power level?

a. The nuclear instrument reads the constant count rate from a neutron source.

b. The rate of power change is dependent on a mean lifetime of the short lived delayed neutron precursors.

c. The delayed neutrons are born at same rate as prompt neutrons after shutdown resulting in a constant neutron count rate.

d. The rate of power change is dependent on a mean lifetime of the longest lived delayed neutron precursors.

Question A.02

[1.0 point]

A reactor is slightly supercritical with the following balues for each of the factors in the six-factor formula:

Fast Fission Factor = 1.03 Fast non-leakage probability = 0.84 Resonance Escape Probability = 0.96 Thermal non-leakage probability = 0.88 Thermal Utilization Factor = 0.70 Reproduction Factor = 1.96 A control rod is inserted to bring the reactor back to critical. Assuming all other factors remain unchanged, the new value for the Thermal Utilization Factor is:

a. 0.698

b. 0.702

c. 0.704

d. 0.708 Question A.03

[1.0 point]

What is the result between a neutron and a target nucleus in elastic scattering?

a. Energy is transferred into nuclear excitation, and then emitted via a gamma emissions.

b. The target nucleus gains the amount of kinetic energy that the neutron loses.

c. The neutron is absorbed by the target nucleus and then emitted with lower kinetic energy.

d. The neutron conserves its initial kinetic energy if the target nucleus is large.

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.04

[1.0 point, 0.25 points each]

Identify if the descriptions or graphs in Column A describe or depict integral control rod worth or differential rod worth?

Column A Column B

a. total reactivity worth of the control rod at that height

1. Differential Rod Worth

b. reactivity change per unit movement of a control rod

2. Integral Rod Worth

c.

d.

Question A.05

[1.0 point]

Which ONE of the following conditions will INCREASE the shutdown margin of a reactor?

a. Lowering moderator temperature (assume negative temperature coefficient)

b. Insertion of a positive reactivity worth experiment

c. Burnout of a burnable poison

d. Fuel depletion Question A.06

[1.0 point]

Reactor period is defined as:

a. The time required for the reactor power to double

b. The time required for reactor power to change by a factor of e

c. The time required for the reactor power to be reduced to one-half the initial level

d. The number of factors of ten that reactor power changes in one minute

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.07

[1.0 point]

Which ONE of the following physical characteristics of the TRIGA fuel is the main contributor for the prompt negative temperature coefficient?

a. As the fuel heats up, the resonance absorption peaks broaden and increases the likelihood of absorption in U-238 and/or Pu-240

b. As the fuel heats up, a rapid increase in moderator temperature occurs through conduction and convection heat transfer mechanisms which adds negative reactivity

c. As the fuel heats up, the oscillating hydrogen in the ZrH lattice imparts energy to a thermal neutron, thereby increasing its mean free path and probability of escape

d. As the fuel heats up, fission product poisons (e.g., Xenon) increase in concentration within the fuel matrix and add negative reactivity via neutron absorption Question A.08

[1.0 point]

What is the effect of U-238 on the reactor neutron life cycle when a neutron energy is below 1 MeV?

a. The number of fissions due to U-238 decrease.

b. The number of fissions due to U-238 remains the same.

c. The number of fissions due to U-238 increase.

d. The number of fissions due to U-235 increase.

Question A.09

[1.0 point]

Which ONE of the reactions below describes a method of production and removal of Xenon?

a. 52Te134 + 53I134 p + 54Xe135 - + 55Cs135 - + 56Ba135

b. 52Te135 + 53I135 - + 54Xe135 0n1 + 54Xe136 - + 56Ba135

c. 52Te135 - + 53I135 - + 54Xe135 - + 55Cs135 - + 56Ba135

d. 52Te134 - + 53I135 - + 54Xe135 + 55Cs135 + + 56Ba135

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.10

[1.0 point]

What is the difference between prompt and delayed neutrons?

a. Prompt neutrons are released virtually instantaneously, and delayed neutrons are a very small fraction of the total number of neutrons and do not have an important role in the control of the reactor.

b. Prompt neutrons are released during fast fission while delayed neutrons are released during thermal fissions.

c. Prompt neutrons are released within 10-13 seconds, whereas delayed neutrons are emitted following the beta decay of a fission fragment.

d. Prompt neutrons are 99% of the neutron produced in fission and are therefore the dominating factor in determining the reactor period, whereas delayed neutrons account for less than 1% of the neutron population and have little effect on the reactor period Question A.11

[1.0 point]

What is the result of the Doppler Effect in the fuel temperature coefficient?

a. Stationary nuclei absorb more neutrons

b. Vibrating nuclei absorb less neutrons

c. Raising the temperature causes the nuclei to vibrate more rapidly effectively broadening the energy range of neutrons that may be resonantly absorbed.

d. An apparent broadening of the nucleis resonances due to a temperature increase.

Question A.12

[1.0 point]

Which ONE of the following best describes the alpha decay () of a nuclide?

a. The number of protons decreases by 2, and the number of neutrons decreases by 2.

b. The number of protons decreases by 2, and the number of neutrons decrease by 4.

c. The number of protons decreases by 4, and the number of neutrons decrease by 2.

d. The number of protons decreases by 4, and the number of neutrons decreases by 4.

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.13

[1.0 point]

Which ONE of the following is the stable reactor period which will result in a power rise from 50% to 100% power in 50 seconds?

a. 14 seconds

b. 36 seconds

c. 72 seconds

d. 144 seconds Question A.14

[1.0 point]

In a subcritical reactor, Keff is increased from 0.885 to 0.943. Which one of the following is the amount of reactivity that was added to the core?

a. 4.68 %k/k

b. 5.58 %k/k

c. 6.94 %k/k

d. 7.45 %k/k Question A.15

[1.0 point]

The first pulse has a reactivity worth of $1.10 which results in a peak power of 500 MW. If the second pulse has a peak power of 5000 MW, the corresponding reactivity worth is:

Given: eff=0.0075

a. $1.32

b. $1.40

c. $1.62

d. $2.02 Question A.16

[1.0 point]

The reactor is subcritical with the count rate of 100 counts per second (cps) and Keff of 0.950.

The control rods are withdrawn until the count rate is doubled. What is the new value of Keff?

a. 1.020

b. 0.998

c. 0.975

d. 0.952

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.17

[1.0 point]

Which of the following is an example of a FERTILE material?

a. Th-232

b. U-233

c. U-235

d. Pu-239 Question A.18

[1.0 point]

Xenon-135 (Xe135) is produced in the reactor by two methods. One is directly from fission; the other is indirectly from the decay of:

a. Xe136

b. Sm136

c. Cs135

d. I135 Question A.19

[1.0 point]

A reactor contains a neutron source that produces 15,000 neutrons/second. The reactor has a keff = 0.88. What is the stable total neutron production rate in the reactor?

a. 100,000 neutrons/sec

b. 115,074 neutrons/sec

c. 125,000 neutrons/sec

d. 135,135 neutrons/sec

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.20

[1.0 point]

Given a source strength of 200 neutrons per second (N/sec) and a multiplication factor of 0.6, which ONE of the following is the expected stable neutron count rate?

a. 150 N/sec

b. 250 N/sec

c. 400 N/sec

d. 500 N/sec

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

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

[1.0 point]

Which ONE of the following changes requires NRC Approval?

a. Revision of the operator licensing requalification examination

b. Revision of Standard Operating Procedure #1 for Use of the Reactor

c. Major changes in the Administrative Procedure #7

d. Delete an administrative control requirement listed in the TXA&M Technical Specification 6.0 Question B.02

[1.0 point]

Who may authorize reentry into the Nuclear Science Center after an evacuation of the facility?

a. Reactor Operator

b. Radiation Safety Officer

c. Emergency Coordinator

d. Emergency Director Question B.03

[1.0 point]

A radioactive source reads 80 mRem/hr on contact. Thirty minutes later, the same source reads 40 mrem/hr. How long is the time for the source to decay from a reading of 80 mrem/hr to 5 mrem/hr?

a. 1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months

b. 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months

c. 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months

d. 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Question B.04

[1.0 point]

Which ONE of the following regulations requires submitting NRC Form 396, Certification of Medical Examination by Facility Licensee, as part of an application for an operator license?

a. 10 CFR 19

b. 10 CFR 20

c. 10 CFR 50

d. 10 CFR 55

Category B: Normal/Emergency Procedures and Radiological Controls Question B.05

[1.0 point]

Which ONE of the following is the renewal requirement for an existing license?

a. Every six months

b. Every year

c. Biennually

d. Every six years Question B.06

[1.0 point]

Which ONE of the following is the surveillance reporting requirement of Ar41 discharge?

a. Every 3 months

b. Twice a year

c. Once a year

d. Every other year Question B.07

[1.0 point]

The Regulating Rod shall be visually inspected __________ while the Transient Rod Drive shall be inspected __________.

a. Monthly, annually

b. Every six months, every year

c. Every year, semiannually

d. Every two years, every six months Question B.08

[1.0 point]

Which ONE of the following radioactive GASES might be an indication of a fuel element leak?

a. N16

b. Ar41

c. Xe135

d. Cs137

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

[1.0 point]

A radioactive source is to be stored in the reactor bay with no shielding. The source reads 2 R/hr at 1 foot. How far from the source does a barrier need to be placed for it to be considered a Radiation Area?

a. 372 m

b. 610 cm

c. 110 cm

d. 30 cm Question B.10

[1.0 point]

The reactor is operating at 10 mrem/hr at the pool radiation area monitor. You are conducting the facility walk-thru portion of your NRC licensing exam with the NRC examiner. How long can the NRC examiner stay before their 10 CFR 20 total ANNUAL effective dose limit is exceeded?

a. 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months

b. 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months

c. 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months

d. 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Question B.11

[1.0 point]

Which ONE of the following is the correct definition of a CHANNEL CHECK?

a. The combination of sensor, line, amplifier, and output device which are connected for the purpose of measuring the value of a parameter.

b. The introduction of a signal into the channel for verification that it is operable.

c. A qualitative verification of acceptable performance by observation of channel behavior.

d. An adjustment of the channel such that its output corresponds with acceptable accuracy to known values of the parameter which the channel measures.

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

[1.0 point]

Which ONE of the following is the definition for Annual Limit on Intake (ALI)?

a. Projected dose commitment values to individuals that warrant protective action following a release of radioactive material.

b. The concentration of a radio-nuclide in air which, if inhaled by an adult worker for a year, results in a total effective dose equivalent of 100 millirem.

c. The effluent concentration of a radio-nuclide in air which, if inhaled continuously over a year, would result in a total effective dose equivalent of 50 millirem for noble gases.

d. 10CFR20 derived limit, based on a Committed Effective Dose Equivalent of 5 Rems whole body or 50 Rems to any individual organ, for the amount of radioactive material inhaled or ingested in a year by an adult worker.

Question B.13

[1.0 point]

You are performing a periodic radiation survey of an area where general radiation readings are approximately 1 mrem/hr. However, you find an old experimental facility in an accessible area not posted for radiological safety reading reading 25 mrem/hr at 30 cm. How would this area be posted in accordance with the requirements of 10 CFR 20?

a. Radiation Area on contact with the experimental facility

b. Radiation Area @ 30 cm from the experimental facility

c. High Radiation Area on contact with the experimental facility

d. High Radiation Area @ 30 cm from the experimental facility Question B.14

[1.0 point]

TXA&M Emergency Preparedness Plan allows a one-time MAXIMUM exposure limit of

__________ to save a life or protect large populations.

a. 5 rem

b. 10 rem

c. 25 rem

d. 50 rem

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

[1.0 point]

Per TXA&M Emergency Classification, which ONE of the following is a failure of an in-core experiment with a minor release of radioactive material?

a. Alert

b. Unusual Event - (reactor related)

c. Safety Event - (non-reactor related)

d. Normal Operation Question B.16

[1.0 point]

The CURIE content of a radioactive source is a measure of

a. number of radioactive atoms in the source.

b. number of nuclear disintegrations per unit time.

c. amount of energy emitted per unit time by the source

d. amount of damage to soft body tissue per unit time.

Question B.17

[1.0 point]

What is the MINIMUM level of management who shall be present at the facility during a recovery from an unplanned or unscheduled shutdown?

a. Reactor Operator

b. Senior Reactor Operator

c. Reactor Facility Director

d. Reactor Operations Committee Question B.18

[1.0 point]

10 CFR 50.59 would require TXA&M submit a request to the NRC for which ONE of the following modifications?

a. Utilize a new Xenon poisoning method of measurement

b. Change of primary coolant pressure gauge with a like model

c. Use new Resistance Temperature Detectors (RTD) to perform reactor power calibration

d. Replace the Wide Range Log with an uncompensated ion chamber

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

[1.0 point]

You use a survey instrument with a window probe to measure the beta-gamma dose rate from an irradiated experiment. The dose rate with the window closed is 160 mrem/hour and 200 mrem/hour with the window open. Which ONE of the following is the gamma dose rate?

a. 40 mrem/hour

b. 140 mrem/hour

c. 160 mrem/hour

d. 360 mrem/hour Question B.20

[1.0 point]

Which ONE of the following are the TXA&M Technical Specification limits for irradiated fuel storage?

a. k-eff <0.95

b. k-eff <0.90

c. k-eff <0.85

d. k-eff <0.80

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

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

[1.0 point, 0.25 each]

Badges indicate the level of access authorized to an individual. Match the level of personnel access in Column A with the respective color-coded badge in Column B.

Column A Column B

a. Unescorted Access

1. Blue

b. Limited Access

2. Green

c. Grounds Access

3. Orange

d. Visitor

4. Yellow Question C.02

[1.0 point]

Which ONE of the following best describes on how the Uncompensated Ion Chamber (UIC) and Compensated Ion Chamber (CIC) operate?

a. The CIC has Two chambers, one is coated with U-235 for fission reaction and the other is coated with Boron-10 for (n,a) reaction; whereas the UIC has only one chamber coated with U-235 for fission reaction.

b. The CIC has only one chamber coated with U-235 for fission reaction, whereas the UIC has two chambers, both can sense gamma rays but only one is coated with Boron-10 for (n,a) reaction.

c. The CIC has two chamber, both can sense gamma rays but only one is coated with Boron-10 for (n,a) reaction; whereas the UIC has only one chamber coated with Boron-10 for (n,a) reaction.

d. The CIC has only one chamber coated with Boron-10 for (n,a) reaction; whereas the UIC has two chambers, one is coated with U-235 for fission reaction and the other is coated with Boron-10 for (n,a) reaction.

Question C.03

[1.0 point]

Which ONE of the following provides a reactor SCRAM in any mode of operation?

a. Low Pool Level

b. High Power Level

c. Loss of Safety Channel Voltage

d. High Fuel Temperature

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

[1.0 point]

What is the nominal Hydrogen-Zirconium atom ratio in the TRIGA LEU fuel elements?

a. 8 Hydrogen atoms to 20 Zirconium atoms

b. 8.5 Hydrogen atoms to 25 Zirconium atoms

c. 1 Hydrogen atom to 1.5 Zirconium atoms

d. 1.6 Hydrogen atoms to 1 Zirconium atoms Question C.05

[1.0 point]

What indications does the Pulse Channel provide after the firing of a pulse?

a. Percent Power and Reactor Period

b. Peak Power and Energy

c. Peak Power and 1kW Interlock

d. Energy and Fuel Temperature Question C.06

[1.0 point]

Which ONE of the following statements is FALSE in reference to the Servo Flux Control System?

a. Alarm if the Reg Rod is inserted less than 20% fully withdrawn

b. Reg Rod moves in response to the signal from the Log Power Channel

c. Reg Rod moves in response to the signal from the Linear Power Channel

d. Reg Rod control is automatically shift back to manual if the level drifts out of +/- 5% range Question C.07

[1.0 point]

Which ONE of the following is the greatest issue/concern as a result of a loss of coolant flow that results in a significant pool leakage and a gradual pool temperature increase?

a. Protection of personnel from radiation hazards

b. Groundwater contamination to the surrounding water table

c. Overheating the TRIGA fuel, that results in cladding failure and fission product release

d. Overheating the TRIGA fuel, that results in Zirconium-Hydride reaction that releases explosive hydrogen gas

Category C: Facility and Radiation Monitoring Systems Question C.08

[1.0 point]

Which ONE of the following is the reason the pneumatic system is vented to the main exhaust stack?

a. Prevent exposure to CO2 that is an asphyxiation hazard

b. Prevent exposure to Ar-41 due to buildup of air in the line

c. Prevent exposure to N-16 due to buildup of water in the line

d. Prevent exposure to fission product gases due to a fuel cladding breach Question C.09

[1.0 point]

Which ONE of the following is the calibration source used to calibrate the Area Radiation Monitor?

a. Argon-40

b. Cobalt-60

c. Iodine-131

d. Cesium-137 Question C.10

[1.0 point]

In the primary purification system, which ONE of the following is the main function of the demineralizer?

a. Absorb H-3 to maintain purity of the pool water

b. Absorb thermal neutrons to increase life of the reactor pool

c. Reduce N-16 formation to reduce the dose rate at the reactor pool

d. Remove soluble impurity to maintain low conductivity in the pool water Question C.11

[1.0 point]

Which ONE of the following Control Rod Drive Mechanisms (CRDM) for the Shim Safety Control Rods holds the control rods in position during reactor operation?

a. Motor

b. Armature

c. Electromagnet

d. Piston

Category C: Facility and Radiation Monitoring Systems Question C.12

[1.0 point]

In the event a Fuel-Followed Control Rod becomes detached from its mounting, what prevents it from falling out of the core?

a. Tapered section above absorber prevents passage through reactor frame

b. Safety plate assembly beneath the reactor grid plate

c. Notch in control rod pole connected to reactor frame

d. Bottom of pool is within two inches of grid plate Question C.13

[1.0 point]

Which ONE of the following air monitor channels is designated as the Fission Product Monitor?

a. 4

b. 3

c. 2

d. 1 Question C.14

[1.0 point]

What is the result when you de-energize the three way solenoid valve to the transient rod?

a. Closes, admitting air to the cylinder

b. Closes, removing air from the cylinder

c. Opens, admitting air to the cylinder

d. Opens, removing air from the cylinder Question C.15

[1.0 point]

What automatic action will occur upon decreasing pool level?

a. Core pump trip

b. Skimmer pump trip

c. Recirculation pump trip

d. Purification pump trip

Category C: Facility and Radiation Monitoring Systems Question C.16

[1.0 point]

Which ONE of the following describes the yellow light associated with the beam port water shutters?

a. Tells experimenter that the beam has been shut-off

b. Warns the experimenter of the commencement of a reactor startup

c. Indicates that the shutter tube is evacuated and the beam is active

d. Indicates that the reactor operator has selected the shutter flood Question C.17

[1.0 point]

A three inch drain line is on which ONE of the following Pool Water Systems?

a. Pool Floor

b. Valve Pit

c. Skimmer System

d. Irradiation Cell Floor Question C.18

[1.0 point]

The Stack Gas Facility Air monitors for which ONE of the following?

a. Argon-41 release

b. Cobalt-60 emission

c. Krypton-85 release

d. Cesium-137 emission

Category C: Facility and Radiation Monitoring Systems Question C.19

[2.0 points, 0.5 each]

Match the input signal listed in Column A with the AUTOMATIC Control System response in Column B. Assume the reactor is in operation. Items in Column B may be used more than once or not at all.

Column A Column B

a. Servo Fault

1. SCRAM

b. Power Channel = 1.25 MW

2. Rod run in

c. Pulse mode shim rod withdrawal

3. Rod Withdraw Prohibit

d. HV Wide Range Linear Channel = 140V

4. Indication ONLY

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

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

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

d

DOE Fundamentals Handbook, NPRT, Vol. 2, Module 3, EO 4.1, p.35 KAPL, Chart of the Nuclides, 17th Ed.

A.10 Answer:

c

Reference:

DOE Fundamentals Handbook, NPRT, Vol., Module 2, EO 3.1, p. 29 A.11 Answer:

c

Reference:

DOE Fundamentals Handbook, NPRT, Vol. 2, Module 3, EO 2.7,p. 26 A.12 Answer a

Reference:

Chart of the Nuclides, KAPL. Seventeenth Edition

Category A: Theory, Thermodynamics & Facility Operating Characteristics A.13 Answer:

c

Reference:

P = P0et/T, T = t / (ln(P/P0) = 50 / (ln(2)) = 72.15 seconds A.14 Answer:

c

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, Section 3.3.4

= (Keff1-Keff2)/(Keff1*Keff2) = (0.943-0.885)/((0.943*0.885) 0.0694k/k = 6.94%k/k A.15 Answer:

a 1=($1)(eff)=($1.10)(.0075)=(.00825)

[(2-eff)^2]/Peak2 = [(1-eff)^2]/Peak1 Peak2/Peak1*[(1-eff)^2]=[(2-eff)^2]

(5000/500)*[(.00825-.0075)^2]= [(2-eff)^2]

[(.000005625)^1/2]+eff =2=.009872

$2=(2/eff)=(.009872/.0075)= $1.316 $1.32

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, 1988. § 4.6, p. 4-16 A.16 Answer:

c

TXA&M Emergency Preparedness Plan 3.4 B.03 Answer:

b

Reference:

DR = DR*e-t = 40 mrem/hr =80 mrem/hr* e -(0.5hr)

Ln(40/80) = -*0.5hr = =1.3863 Solve for t: Ln(5/80)=-1.3863 (t) = t=2 hours Short cut:

TXA&M Technical Specifications, Definitions

Reference:

TXA&M SOP VII Procedure B12

TXA&M Technical Specification 3.3 and TXA&M SAR 7.0

January 10, 2018 Dr. Sean McDeavitt, Director Nuclear Science Center Texas A&M University 1095 Nuclear Science Road College Station, TX 77843

SUBJECT:

EXAMINATION REPORT NO. 50-128/OL-18-01, TEXAS A&M UNIVERSITY

Dear Dr. McDeavitt:

During the week of November 6, 2017, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your Texas A&M University Nuclear Science Center (NSC) 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 (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site 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 Ms. Michele DeSouza at (301) 415-0747 or via e-mail at Michele.DeSouza@nrc.gov.

Sincerely,

/RA/

Anthony J. Mendiola, Chief Research and Test Reactors Oversight Branch Division of Licensing Projects Office of Nuclear Reactor Regulation Docket No. 50-128

Enclosures:

1. Examination Report No. 50-128/OL-18-01

2. Written Examination cc: w/o enclosures: See next page

ML17331B447 NRR-079 OFFICE NRR/DLP/PROB:CE NRR/DIRS/IOLB:LA NRR/DLP/PROB:BC NAME MDeSouza ABaxter AMendiola DATE 11/27/2017 11/27/2017 01/10/2018

Texas A&M University Docket No. 50-128 cc:

Mayor, City of College Station P.O. Box Drawer 9960 College Station, TX 77840-3575 Governors Budget and Policy Office PO Box 12428 Austin, Texas 78711-2428 Dr. Dimitris C. Lagoudas, Deputy Director Texas A&M University System Texas A&M Engineering Experiment Station 241 Zachry Engineering Center College Station, Texas 77843 Mr. Jerry Newhouse, Assistant Director Nuclear Science Center Texas A&M University Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, MS 3575 College Station, Texas 77843 Radiation Program Officer Bureau of Radiation Control Dept. Of State Health Services Division for Regulatory Services 1100 West 49th Street, MC 2828 Austin, TX 78756-3189 Technical Advisor Office of Permitting, Remediation &

Registration Texas Commission on Environmental Quality P.O. Box 13087, MS 122 Austin, TX 78711-3087 Test, Research and Training Reactor Newsletter P.O. Box 118300 University of Florida Gainesville, FL 32611 Mr. Scott Miller, Manager Reactor Operations Texas A&M University Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, MS 3575 College Station, Texas 77843 State Energy Conservation Office Comptroller of Public Accounts P.O. Box 13528 Austin, TX 78711-3528 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.:

50-128/OL-18-01 FACILITY DOCKET NO.:

50-128 FACILITY LICENSE NO.:

R-83 FACILITY:

Texas A & M NSC EXAMINATION DATES:

November 6-10, 2017 SUBMITTED BY:

____/RA/ ________________

__01/10/2018__

Michele DeSouza, Chief Examiner Date

SUMMARY

During the week of November 6, 2017, the NRC administered an operator licensing examination to two Senior Reactor Operator Upgrade (SRO-U) candidates, one Senior Reactor Operator Instant (SRO-I), and two Reactor Operator (RO) candidates. The candidates passed all applicable portions of the examinations.

REPORT DETAILS

1.

Examiner:

Michele 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 3/0 5/0 Overall 2/0 3/0 5/0

3.

Exit Meeting:

Michele C. DeSouza, Chief Examiner, NRC Jerry Newhouse, Associate Director, TXA&M NSC Scott Miller, Manager, Reactor Operations, TXA&M NSC Cameron Macdonald, Reactor Supervisor, TXA&M NSC Per discussion with the facility, prior to administration of the examination, adjustments were accepted. Upon completion of the examination, the NRC Examiner met with facility staff representatives to discuss the results. Based on candidate responses, the NRC recommended the facility emphasize utilization to TXA&M Standard Operating Procedures as appropriate. At the conclusion of the meeting, the NRC examiner thanked the facility for their support in the administration of the examination.

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

TX A&M NSC REACTOR TYPE:

TRIGA DATE ADMINISTERED:

11/09/2017 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

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 ___ (0.25 each)

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 ___

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 ___

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 ___

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 ___ (0.25 each)

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 ___ (0.50 each)

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

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

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.

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

=

te P

P 0

eff K

S S

SCR

=

1

sec 10 1

4

x

=

+

=

eff SUR 06 26

(

)

(

)

2 1

1 1

2 1

eff eff K

CR K

CR

=

(

)

(

)

2 2

1 1

=

CR CR 2

1 1

1 eff eff K

K M

=

1 2

1 1

CR CR K

M eff

=

)

(

0 10 t

SUR P

P=

(

)

0 1

P P

=

eff eff K

K SDM

=1

=

+

=

eff 2

1 1

2 eff eff eff eff K

K K

K

=

693

.0 2

1 =

T eff eff K

K 1

=

t e

DR DR

=

0

( )

2 6

R n

E Ci DR=

2 2

1 1

d DR d

DR

=

(

)

(

)

1 2

2 2

Peak Peak

=

T UA H

m T

c m

Q P

=

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.01

[1.0 point]

What is the reason the stable negative period following a scram is always the same value (- 80 second) regardless of initial power level?

a. The nuclear instrument reads the constant count rate from a neutron source.

b. The rate of power change is dependent on a mean lifetime of the short lived delayed neutron precursors.

c. The delayed neutrons are born at same rate as prompt neutrons after shutdown resulting in a constant neutron count rate.

d. The rate of power change is dependent on a mean lifetime of the longest lived delayed neutron precursors.

Question A.02

[1.0 point]

A reactor is slightly supercritical with the following balues for each of the factors in the six-factor formula:

Fast Fission Factor = 1.03 Fast non-leakage probability = 0.84 Resonance Escape Probability = 0.96 Thermal non-leakage probability = 0.88 Thermal Utilization Factor = 0.70 Reproduction Factor = 1.96 A control rod is inserted to bring the reactor back to critical. Assuming all other factors remain unchanged, the new value for the Thermal Utilization Factor is:

a. 0.698

b. 0.702

c. 0.704

d. 0.708 Question A.03

[1.0 point]

What is the result between a neutron and a target nucleus in elastic scattering?

a. Energy is transferred into nuclear excitation, and then emitted via a gamma emissions.

b. The target nucleus gains the amount of kinetic energy that the neutron loses.

c. The neutron is absorbed by the target nucleus and then emitted with lower kinetic energy.

d. The neutron conserves its initial kinetic energy if the target nucleus is large.

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.04

[1.0 point, 0.25 points each]

Identify if the descriptions or graphs in Column A describe or depict integral control rod worth or differential rod worth?

Column A Column B

a. total reactivity worth of the control rod at that height

1. Differential Rod Worth

b. reactivity change per unit movement of a control rod

2. Integral Rod Worth

c.

d.

Question A.05

[1.0 point]

Which ONE of the following conditions will INCREASE the shutdown margin of a reactor?

a. Lowering moderator temperature (assume negative temperature coefficient)

b. Insertion of a positive reactivity worth experiment

c. Burnout of a burnable poison

d. Fuel depletion Question A.06

[1.0 point]

Reactor period is defined as:

a. The time required for the reactor power to double

b. The time required for reactor power to change by a factor of e

c. The time required for the reactor power to be reduced to one-half the initial level

d. The number of factors of ten that reactor power changes in one minute

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.07

[1.0 point]

Which ONE of the following physical characteristics of the TRIGA fuel is the main contributor for the prompt negative temperature coefficient?

a. As the fuel heats up, the resonance absorption peaks broaden and increases the likelihood of absorption in U-238 and/or Pu-240

b. As the fuel heats up, a rapid increase in moderator temperature occurs through conduction and convection heat transfer mechanisms which adds negative reactivity

c. As the fuel heats up, the oscillating hydrogen in the ZrH lattice imparts energy to a thermal neutron, thereby increasing its mean free path and probability of escape

d. As the fuel heats up, fission product poisons (e.g., Xenon) increase in concentration within the fuel matrix and add negative reactivity via neutron absorption Question A.08

[1.0 point]

What is the effect of U-238 on the reactor neutron life cycle when a neutron energy is below 1 MeV?

a. The number of fissions due to U-238 decrease.

b. The number of fissions due to U-238 remains the same.

c. The number of fissions due to U-238 increase.

d. The number of fissions due to U-235 increase.

Question A.09

[1.0 point]

Which ONE of the reactions below describes a method of production and removal of Xenon?

a. 52Te134 + 53I134 p + 54Xe135 - + 55Cs135 - + 56Ba135

b. 52Te135 + 53I135 - + 54Xe135 0n1 + 54Xe136 - + 56Ba135

c. 52Te135 - + 53I135 - + 54Xe135 - + 55Cs135 - + 56Ba135

d. 52Te134 - + 53I135 - + 54Xe135 + 55Cs135 + + 56Ba135

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.10

[1.0 point]

What is the difference between prompt and delayed neutrons?

a. Prompt neutrons are released virtually instantaneously, and delayed neutrons are a very small fraction of the total number of neutrons and do not have an important role in the control of the reactor.

b. Prompt neutrons are released during fast fission while delayed neutrons are released during thermal fissions.

c. Prompt neutrons are released within 10-13 seconds, whereas delayed neutrons are emitted following the beta decay of a fission fragment.

d. Prompt neutrons are 99% of the neutron produced in fission and are therefore the dominating factor in determining the reactor period, whereas delayed neutrons account for less than 1% of the neutron population and have little effect on the reactor period Question A.11

[1.0 point]

What is the result of the Doppler Effect in the fuel temperature coefficient?

a. Stationary nuclei absorb more neutrons

b. Vibrating nuclei absorb less neutrons

c. Raising the temperature causes the nuclei to vibrate more rapidly effectively broadening the energy range of neutrons that may be resonantly absorbed.

d. An apparent broadening of the nucleis resonances due to a temperature increase.

Question A.12

[1.0 point]

Which ONE of the following best describes the alpha decay () of a nuclide?

a. The number of protons decreases by 2, and the number of neutrons decreases by 2.

b. The number of protons decreases by 2, and the number of neutrons decrease by 4.

c. The number of protons decreases by 4, and the number of neutrons decrease by 2.

d. The number of protons decreases by 4, and the number of neutrons decreases by 4.

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.13

[1.0 point]

Which ONE of the following is the stable reactor period which will result in a power rise from 50% to 100% power in 50 seconds?

a. 14 seconds

b. 36 seconds

c. 72 seconds

d. 144 seconds Question A.14

[1.0 point]

In a subcritical reactor, Keff is increased from 0.885 to 0.943. Which one of the following is the amount of reactivity that was added to the core?

a. 4.68 %k/k

b. 5.58 %k/k

c. 6.94 %k/k

d. 7.45 %k/k Question A.15

[1.0 point]

The first pulse has a reactivity worth of $1.10 which results in a peak power of 500 MW. If the second pulse has a peak power of 5000 MW, the corresponding reactivity worth is:

Given: eff=0.0075

a. $1.32

b. $1.40

c. $1.62

d. $2.02 Question A.16

[1.0 point]

The reactor is subcritical with the count rate of 100 counts per second (cps) and Keff of 0.950.

The control rods are withdrawn until the count rate is doubled. What is the new value of Keff?

a. 1.020

b. 0.998

c. 0.975

d. 0.952

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.17

[1.0 point]

Which of the following is an example of a FERTILE material?

a. Th-232

b. U-233

c. U-235

d. Pu-239 Question A.18

[1.0 point]

Xenon-135 (Xe135) is produced in the reactor by two methods. One is directly from fission; the other is indirectly from the decay of:

a. Xe136

b. Sm136

c. Cs135

d. I135 Question A.19

[1.0 point]

A reactor contains a neutron source that produces 15,000 neutrons/second. The reactor has a keff = 0.88. What is the stable total neutron production rate in the reactor?

a. 100,000 neutrons/sec

b. 115,074 neutrons/sec

c. 125,000 neutrons/sec

d. 135,135 neutrons/sec

Category A: Theory, Thermodynamics & Facility Operating Characteristics Question A.20

[1.0 point]

Given a source strength of 200 neutrons per second (N/sec) and a multiplication factor of 0.6, which ONE of the following is the expected stable neutron count rate?

a. 150 N/sec

b. 250 N/sec

c. 400 N/sec

d. 500 N/sec

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

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

[1.0 point]

Which ONE of the following changes requires NRC Approval?

a. Revision of the operator licensing requalification examination

b. Revision of Standard Operating Procedure #1 for Use of the Reactor

c. Major changes in the Administrative Procedure #7

d. Delete an administrative control requirement listed in the TXA&M Technical Specification 6.0 Question B.02

[1.0 point]

Who may authorize reentry into the Nuclear Science Center after an evacuation of the facility?

a. Reactor Operator

b. Radiation Safety Officer

c. Emergency Coordinator

d. Emergency Director Question B.03

[1.0 point]

A radioactive source reads 80 mRem/hr on contact. Thirty minutes later, the same source reads 40 mrem/hr. How long is the time for the source to decay from a reading of 80 mrem/hr to 5 mrem/hr?

a. 1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months

b. 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months

c. 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months

d. 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Question B.04

[1.0 point]

Which ONE of the following regulations requires submitting NRC Form 396, Certification of Medical Examination by Facility Licensee, as part of an application for an operator license?

a. 10 CFR 19

b. 10 CFR 20

c. 10 CFR 50

d. 10 CFR 55

Category B: Normal/Emergency Procedures and Radiological Controls Question B.05

[1.0 point]

Which ONE of the following is the renewal requirement for an existing license?

a. Every six months

b. Every year

c. Biennually

d. Every six years Question B.06

[1.0 point]

Which ONE of the following is the surveillance reporting requirement of Ar41 discharge?

a. Every 3 months

b. Twice a year

c. Once a year

d. Every other year Question B.07

[1.0 point]

The Regulating Rod shall be visually inspected __________ while the Transient Rod Drive shall be inspected __________.

a. Monthly, annually

b. Every six months, every year

c. Every year, semiannually

d. Every two years, every six months Question B.08

[1.0 point]

Which ONE of the following radioactive GASES might be an indication of a fuel element leak?

a. N16

b. Ar41

c. Xe135

d. Cs137

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

[1.0 point]

A radioactive source is to be stored in the reactor bay with no shielding. The source reads 2 R/hr at 1 foot. How far from the source does a barrier need to be placed for it to be considered a Radiation Area?

a. 372 m

b. 610 cm

c. 110 cm

d. 30 cm Question B.10

[1.0 point]

The reactor is operating at 10 mrem/hr at the pool radiation area monitor. You are conducting the facility walk-thru portion of your NRC licensing exam with the NRC examiner. How long can the NRC examiner stay before their 10 CFR 20 total ANNUAL effective dose limit is exceeded?

a. 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months

b. 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months

c. 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months

d. 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Question B.11

[1.0 point]

Which ONE of the following is the correct definition of a CHANNEL CHECK?

a. The combination of sensor, line, amplifier, and output device which are connected for the purpose of measuring the value of a parameter.

b. The introduction of a signal into the channel for verification that it is operable.

c. A qualitative verification of acceptable performance by observation of channel behavior.

d. An adjustment of the channel such that its output corresponds with acceptable accuracy to known values of the parameter which the channel measures.

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

[1.0 point]

Which ONE of the following is the definition for Annual Limit on Intake (ALI)?

a. Projected dose commitment values to individuals that warrant protective action following a release of radioactive material.

b. The concentration of a radio-nuclide in air which, if inhaled by an adult worker for a year, results in a total effective dose equivalent of 100 millirem.

c. The effluent concentration of a radio-nuclide in air which, if inhaled continuously over a year, would result in a total effective dose equivalent of 50 millirem for noble gases.

d. 10CFR20 derived limit, based on a Committed Effective Dose Equivalent of 5 Rems whole body or 50 Rems to any individual organ, for the amount of radioactive material inhaled or ingested in a year by an adult worker.

Question B.13

[1.0 point]

You are performing a periodic radiation survey of an area where general radiation readings are approximately 1 mrem/hr. However, you find an old experimental facility in an accessible area not posted for radiological safety reading reading 25 mrem/hr at 30 cm. How would this area be posted in accordance with the requirements of 10 CFR 20?

a. Radiation Area on contact with the experimental facility

b. Radiation Area @ 30 cm from the experimental facility

c. High Radiation Area on contact with the experimental facility

d. High Radiation Area @ 30 cm from the experimental facility Question B.14

[1.0 point]

TXA&M Emergency Preparedness Plan allows a one-time MAXIMUM exposure limit of

__________ to save a life or protect large populations.

a. 5 rem

b. 10 rem

c. 25 rem

d. 50 rem

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

[1.0 point]

Per TXA&M Emergency Classification, which ONE of the following is a failure of an in-core experiment with a minor release of radioactive material?

a. Alert

b. Unusual Event - (reactor related)

c. Safety Event - (non-reactor related)

d. Normal Operation Question B.16

[1.0 point]

The CURIE content of a radioactive source is a measure of

a. number of radioactive atoms in the source.

b. number of nuclear disintegrations per unit time.

c. amount of energy emitted per unit time by the source

d. amount of damage to soft body tissue per unit time.

Question B.17

[1.0 point]

What is the MINIMUM level of management who shall be present at the facility during a recovery from an unplanned or unscheduled shutdown?

a. Reactor Operator

b. Senior Reactor Operator

c. Reactor Facility Director

d. Reactor Operations Committee Question B.18

[1.0 point]

10 CFR 50.59 would require TXA&M submit a request to the NRC for which ONE of the following modifications?

a. Utilize a new Xenon poisoning method of measurement

b. Change of primary coolant pressure gauge with a like model

c. Use new Resistance Temperature Detectors (RTD) to perform reactor power calibration

d. Replace the Wide Range Log with an uncompensated ion chamber

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

[1.0 point]

You use a survey instrument with a window probe to measure the beta-gamma dose rate from an irradiated experiment. The dose rate with the window closed is 160 mrem/hour and 200 mrem/hour with the window open. Which ONE of the following is the gamma dose rate?

a. 40 mrem/hour

b. 140 mrem/hour

c. 160 mrem/hour

d. 360 mrem/hour Question B.20

[1.0 point]

Which ONE of the following are the TXA&M Technical Specification limits for irradiated fuel storage?

a. k-eff <0.95

b. k-eff <0.90

c. k-eff <0.85

d. k-eff <0.80

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

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

[1.0 point, 0.25 each]

Badges indicate the level of access authorized to an individual. Match the level of personnel access in Column A with the respective color-coded badge in Column B.

Column A Column B

a. Unescorted Access

1. Blue

b. Limited Access

2. Green

c. Grounds Access

3. Orange

d. Visitor

4. Yellow Question C.02

[1.0 point]

Which ONE of the following best describes on how the Uncompensated Ion Chamber (UIC) and Compensated Ion Chamber (CIC) operate?

a. The CIC has Two chambers, one is coated with U-235 for fission reaction and the other is coated with Boron-10 for (n,a) reaction; whereas the UIC has only one chamber coated with U-235 for fission reaction.

b. The CIC has only one chamber coated with U-235 for fission reaction, whereas the UIC has two chambers, both can sense gamma rays but only one is coated with Boron-10 for (n,a) reaction.

c. The CIC has two chamber, both can sense gamma rays but only one is coated with Boron-10 for (n,a) reaction; whereas the UIC has only one chamber coated with Boron-10 for (n,a) reaction.

d. The CIC has only one chamber coated with Boron-10 for (n,a) reaction; whereas the UIC has two chambers, one is coated with U-235 for fission reaction and the other is coated with Boron-10 for (n,a) reaction.

Question C.03

[1.0 point]

Which ONE of the following provides a reactor SCRAM in any mode of operation?

a. Low Pool Level

b. High Power Level

c. Loss of Safety Channel Voltage

d. High Fuel Temperature

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

[1.0 point]

What is the nominal Hydrogen-Zirconium atom ratio in the TRIGA LEU fuel elements?

a. 8 Hydrogen atoms to 20 Zirconium atoms

b. 8.5 Hydrogen atoms to 25 Zirconium atoms

c. 1 Hydrogen atom to 1.5 Zirconium atoms

d. 1.6 Hydrogen atoms to 1 Zirconium atoms Question C.05

[1.0 point]

What indications does the Pulse Channel provide after the firing of a pulse?

a. Percent Power and Reactor Period

b. Peak Power and Energy

c. Peak Power and 1kW Interlock

d. Energy and Fuel Temperature Question C.06

[1.0 point]

Which ONE of the following statements is FALSE in reference to the Servo Flux Control System?

a. Alarm if the Reg Rod is inserted less than 20% fully withdrawn

b. Reg Rod moves in response to the signal from the Log Power Channel

c. Reg Rod moves in response to the signal from the Linear Power Channel

d. Reg Rod control is automatically shift back to manual if the level drifts out of +/- 5% range Question C.07

[1.0 point]

Which ONE of the following is the greatest issue/concern as a result of a loss of coolant flow that results in a significant pool leakage and a gradual pool temperature increase?

a. Protection of personnel from radiation hazards

b. Groundwater contamination to the surrounding water table

c. Overheating the TRIGA fuel, that results in cladding failure and fission product release

d. Overheating the TRIGA fuel, that results in Zirconium-Hydride reaction that releases explosive hydrogen gas

Category C: Facility and Radiation Monitoring Systems Question C.08

[1.0 point]

Which ONE of the following is the reason the pneumatic system is vented to the main exhaust stack?

a. Prevent exposure to CO2 that is an asphyxiation hazard

b. Prevent exposure to Ar-41 due to buildup of air in the line

c. Prevent exposure to N-16 due to buildup of water in the line

d. Prevent exposure to fission product gases due to a fuel cladding breach Question C.09

[1.0 point]

Which ONE of the following is the calibration source used to calibrate the Area Radiation Monitor?

a. Argon-40

b. Cobalt-60

c. Iodine-131

d. Cesium-137 Question C.10

[1.0 point]

In the primary purification system, which ONE of the following is the main function of the demineralizer?

a. Absorb H-3 to maintain purity of the pool water

b. Absorb thermal neutrons to increase life of the reactor pool

c. Reduce N-16 formation to reduce the dose rate at the reactor pool

d. Remove soluble impurity to maintain low conductivity in the pool water Question C.11

[1.0 point]

Which ONE of the following Control Rod Drive Mechanisms (CRDM) for the Shim Safety Control Rods holds the control rods in position during reactor operation?

a. Motor

b. Armature

c. Electromagnet

d. Piston

Category C: Facility and Radiation Monitoring Systems Question C.12

[1.0 point]

In the event a Fuel-Followed Control Rod becomes detached from its mounting, what prevents it from falling out of the core?

a. Tapered section above absorber prevents passage through reactor frame

b. Safety plate assembly beneath the reactor grid plate

c. Notch in control rod pole connected to reactor frame

d. Bottom of pool is within two inches of grid plate Question C.13

[1.0 point]

Which ONE of the following air monitor channels is designated as the Fission Product Monitor?

a. 4

b. 3

c. 2

d. 1 Question C.14

[1.0 point]

What is the result when you de-energize the three way solenoid valve to the transient rod?

a. Closes, admitting air to the cylinder

b. Closes, removing air from the cylinder

c. Opens, admitting air to the cylinder

d. Opens, removing air from the cylinder Question C.15

[1.0 point]

What automatic action will occur upon decreasing pool level?

a. Core pump trip

b. Skimmer pump trip

c. Recirculation pump trip

d. Purification pump trip

Category C: Facility and Radiation Monitoring Systems Question C.16

[1.0 point]

Which ONE of the following describes the yellow light associated with the beam port water shutters?

a. Tells experimenter that the beam has been shut-off

b. Warns the experimenter of the commencement of a reactor startup

c. Indicates that the shutter tube is evacuated and the beam is active

d. Indicates that the reactor operator has selected the shutter flood Question C.17

[1.0 point]

A three inch drain line is on which ONE of the following Pool Water Systems?

a. Pool Floor

b. Valve Pit

c. Skimmer System

d. Irradiation Cell Floor Question C.18

[1.0 point]

The Stack Gas Facility Air monitors for which ONE of the following?

a. Argon-41 release

b. Cobalt-60 emission

c. Krypton-85 release

d. Cesium-137 emission

Category C: Facility and Radiation Monitoring Systems Question C.19

[2.0 points, 0.5 each]

Match the input signal listed in Column A with the AUTOMATIC Control System response in Column B. Assume the reactor is in operation. Items in Column B may be used more than once or not at all.

Column A Column B

a. Servo Fault

1. SCRAM

b. Power Channel = 1.25 MW

2. Rod run in

c. Pulse mode shim rod withdrawal

3. Rod Withdraw Prohibit

d. HV Wide Range Linear Channel = 140V

4. Indication ONLY

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

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

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

d

DOE Fundamentals Handbook, NPRT, Vol. 2, Module 3, EO 4.1, p.35 KAPL, Chart of the Nuclides, 17th Ed.

A.10 Answer:

c

Reference:

DOE Fundamentals Handbook, NPRT, Vol., Module 2, EO 3.1, p. 29 A.11 Answer:

c

Reference:

DOE Fundamentals Handbook, NPRT, Vol. 2, Module 3, EO 2.7,p. 26 A.12 Answer a

Reference:

Chart of the Nuclides, KAPL. Seventeenth Edition

Category A: Theory, Thermodynamics & Facility Operating Characteristics A.13 Answer:

c

Reference:

P = P0et/T, T = t / (ln(P/P0) = 50 / (ln(2)) = 72.15 seconds A.14 Answer:

c

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, Section 3.3.4

= (Keff1-Keff2)/(Keff1*Keff2) = (0.943-0.885)/((0.943*0.885) 0.0694k/k = 6.94%k/k A.15 Answer:

a 1=($1)(eff)=($1.10)(.0075)=(.00825)

[(2-eff)^2]/Peak2 = [(1-eff)^2]/Peak1 Peak2/Peak1*[(1-eff)^2]=[(2-eff)^2]

(5000/500)*[(.00825-.0075)^2]= [(2-eff)^2]

[(.000005625)^1/2]+eff =2=.009872

$2=(2/eff)=(.009872/.0075)= $1.316 $1.32

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, 1988. § 4.6, p. 4-16 A.16 Answer:

c

TXA&M Emergency Preparedness Plan 3.4 B.03 Answer:

b

Reference:

DR = DR*e-t = 40 mrem/hr =80 mrem/hr* e -(0.5hr)

Ln(40/80) = -*0.5hr = =1.3863 Solve for t: Ln(5/80)=-1.3863 (t) = t=2 hours Short cut:

TXA&M Technical Specifications, Definitions

Reference:

TXA&M SOP VII Procedure B12

TXA&M Technical Specification 3.3 and TXA&M SAR 7.0