ML23269A190

Examination Report Letter No. 50-005/OL-23-01, Pennsylvania State University

ML23269A190
Person / Time
Site:	Pennsylvania State University
Issue date:	09/27/2023
From:	Travis Tate NRC/NRR/DANU/UNPO
To:	Unlu K Pennsylvania State Univ
References
50-005/23-001
Download: ML23269A190 (1)

Text

September 27, 2023 Dr. Kenan Unlu, Director The Pennsylvania State University Breazeale Nuclear Reactor Radiation Science and Engineering Center University Park, PA 16802-2301

SUBJECT:

EXAMINATION REPORT NO. 50-005/OL-23-01, PENNSYLVANNIA STATE UNIVERSITY BREAZEALE RESEARCH REACTOR

Dear Dr. Unlu:

During the week of August 21, 2023, the U.S. Nuclear Regulatory Commission (NRC) administered an operator licensing examination at your Pennsylvania State University Breazeale research reactor. The examinations were conducted according to NUREG-1478, "Operator Licensing Examiner Standards for Research and Test Reactors," Revision 2.

Examination questions and preliminary findings were discussed with those members of your staff identified in the enclosed report at the conclusion of the examination.

In accordance with Title 10 of the Code of Federal Regulations, Section 2.390, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. Should you have any questions concerning this examination, please contact John Nguyen at (301) 415-4007 or via email at John.Nguyen@nrc.gov.

Sincerely, Signed by Tate, Travis on 09/27/23 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.50-005

Enclosures:

1. Examination Report No. 50-005/OL-23-01

2. Written Examination cc: w/enclosures to GovDelivery Subscribers

ML23269A190 NRR-079 OFFICE NRR/DANU/UNPO/CE NRR/DANU/UNPO/OLA NRR/DANU/UNPO/BC NAME JNguyen NJones TTate DATE 9/26/2023 9/26/2023 9/27/2023 U.S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-005/OL-23-01 FACILITY DOCKET NO.: 50-005 FACILITY LICENSE NO.: R-2 FACILITY: Pennsylvania State University Breazeal Research Reactor EXAMINATION DATES: August 21-24, 2023 SUBMITTED BY: John Nguyen 09/15/2023 John T. Nguyen, Chief Examiner Date

SUMMARY

During the week of August 21, 2023, the NRC administered operator licensing examinations to one Senior Reactor Operator - Instant (SRO-I), and one Reactor Operator (RO) candidates.

The candidates passed all applicable portions of the examinations.

REPORT DETAILS

1. Examiner: John T. Nguyen, Chief Examiner, NRC

2. Results:

RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 1/0 1/0 2/0 Operating Tests 1/0 1/0 2/0 Overall 1/0 1/0 2/0

3. Exit Meeting:

Tuan D. Le, Reactor Engineer (RTR Examiner-in-Training), NRC John T. Nguyen, Chief Examiner, NRC Jeffrey A. Geuther, Associate Director, PSBR Sean M. Herrmann, Training Coordinator, PSBR Facility comments were accepted prior to the administration of the written examination.

At the conclusion of the meeting, the NRC examiner thanked the facility for their support in the administration of the examinations. The examiner noted that all candidates were well prepared for the examinations.

Enclosure 1

PENNSYLVANIA STATE UNIVERSITY Operator Licensing Examination Week of August 21, 2023 Enclosure 2

U.S. NUCLEAR REGULATORY COMMISSION NON-POWER REACTOR LICENSE EXAMINATION FACILITY: Pennsylvania State Breazeale Reactor REACTOR TYPE: TRIGA DATE ADMINISTERED: 08/24/2023 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 COGE NTROLS 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 ANSWER SHEET Multiple Choice (Circle or X your choice)

If you change your Answer, write your selection in the blank.

A01 a b c d ___

A02 a b c d ___

A03 a b c d ___

A04 a b c d ___

A05 a b c d ___

A06 a b c d ___

A07 a b c d ___

A08 a b c d ___

A09 a b c d ___

A10 a b c d ___

A11 a b c d ___

A12 a b c d ___

A13 a b c d ___

A14 a b c d ___

A15 a b c d ___

A16 a b c d ___

A17 a b c d ___

A18 a b c d ___

A19 a b c d ___

A20 a b c d ___

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

Category B - Normal/Emergency Operating Procedures and Radiological Controls ANSWER SHEET 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 ______ (0.25 each)

B16 a b c d ___

B17 a ______ b ______ c ______ d ______ (0.25 each)

B18 a b c d ___

B19 a b c d ___

B20 a b c d ___

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

C. PLANT AND RAD MONITORING SYSTEMS ANSWER SHEET Multiple Choice (Circle or X your choice)

If you change your Answer, write your selection in the blank.

C01 a b c d ___

C02 a b c d ___

C03 a b c d ___

C04 a b c d ___

C05 a b c d ___

C06 a b c d ___

C07 a b c d ___

C08 a b c d ___

C09 a b c d ___

C10 a b c d ___

C11 a b c d ___

C12 a b c d ___

C13 a b c d ___

C14 a b c d ___

C15 a b c d ___

C16 a b c d ___

C17 a b c d ___

C18 a b c d ___

C19 a b c d ___

C20 a b c d ___

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

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

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

2 Q m c P T m H UAT Pmax eff 0.1sec 1 2

t P P0 e S S SCR

• 110 4 sec 1 K eff SUR 26 .06 eff CR1 1 K eff1 CR2 1 K eff 2 CR1 1 CR2 2 1 M 1 CR 2

P P0 1 K eff CR1 P P0 10 SUR (t )

1 K eff1 1 K eff

• M SDM 1 K eff 2 K eff

= + 0.693 K eff 2 K eff1 T1 2

K eff1 K eff 2 K eff 1 DR DR0 e t 2 DR1 d1 DR2 d 2 2

K eff 6 Ci E n 2 2 1 2 DR R2 Peak2 Peak1 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 QUESTION A.01 [1.0 point]

In the following graph, how is the neutron behavior within the Region II best described?

The neutron microscopic absorption cross-section, a, generally ...

a. decreases as the mass of the target nucleus increases.

b. increases as the mass of the target nucleus increases.

c. increases as neutron energy increases.

d. decreases as neutron energy increases.

QUESTION A.02 [1.0 point]

Which of the following radiation types has its penetrating ability through biological material impeded the greatest by its high specific ionization?

a. Alpha

b. Beta

c. Gamma

d. Neutron QUESTION A.03 [1.0 point]

Which ONE of the following statements MOST correctly describe the prompt neutrons?

a. They are the total fraction of all neutrons born.

b. They are released directly from fission within 10-13 seconds of the fission event.

c. They are emitted immediately following the first beta decay of a fission fragment.

d. They are responsible for the ability to control the rate at which power can rise in a reactor.

QUESTION A.04 [1.0 point]

Which ONE of the following is the most correct time period in which the MAXIMUM amount of Xe-135 will be present in the core?

a. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after a startup to 100% power.

b. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after a scram from 100% power.

c. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after a power increase from 50% to 100%.

d. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after a power decrease from 100% to 50%.

QUESTION A.05 [1.0 point]

Which ONE of the following describes the difference between reflectors and moderators?

a. Reflectors decrease core leakage while moderators thermalize neutrons.

b. Reflectors shield against neutrons while moderators decrease core leakage.

c. Reflectors decrease thermal leakage while moderators decrease fast leakage.

d. Reflectors thermalize neutrons while moderators decrease core leakage.

QUESTION A.06 [1.0 point]

Complete the following sentence:

Due to greater neutron ______ and less ______ by D2O than by H2O, the power in the front of the core is enhanced when the reactor is operated against the D2O tank. (The enhancement produces a change in indications equivalent to about 10% of the indicated power level at 100 kW.)

a. reflection, absorption

b. absorption, reflection

c. capture, activation

d. activation, capture QUESTION A.07 [1.0 point]

The reactor has scrammed following an extended period of operation at full power. Which one of the following accounts for a majority of the heat generated one (1) hour after the scram?

a. Spontaneous fissions.

b. Delayed neutron fissions.

c. Alpha fission product decay.

d. Beta fission product decay.

QUESTION A.08 [1.0 point]

As primary coolant temperature increases, control rod worth:

a. decreases due to lower reflector efficiency.

b. decreases due to higher neutron absorption in the moderator.

c. increases due to the increase in thermal diffusion length.

d. remains the same due to constant poison cross-section of the control rods.

QUESTION A.09 [1.0 point]

The moderator temperature coefficient for a reactor is -0.00082 k/k/oF. What the total reactivity change caused by a temperature decrease of 10oF?

a. 0.0015 k/k

b. 0.0028 k/k

c. 0.0041 k/k

d. 0.0082 k/k QUESTION A.10 [1.0 point]

A few minutes following a reactor scram at full power, the reactor period has stabilized and the power level is decreasing at a CONSTANT rate. What is a reactor power level two minutes later from 1 kW?

a. 975 W

b. 446 W

c. 223 W

d. 111 W QUESTION A.11 [1.0 point]

Reactor A increases power from 10% to 20% with a period of 25 seconds. Reactor B increases power from 80% to 100% with a period of also 25 seconds. Compared to Reactor A, the time required for the power increase of Reactor B is:

a. longer than A.

b. exactly the same as A.

c. twice that of A.

d. shorter than A.

QUESTION A.12 [1.0 point]

A reactor is subcritical with a Keff of 0.955. A positive reactivity of 0.030 k/k is inserted into the core, which ONE of the following best describes the reactor kinetics?

a. The reactor is sub-critical.

b. The reactor is critical.

c. The reactor is super-critical.

d. The reactor is prompt-critical.

QUESTION A.13 [1.0 point]

Which ONE of the following conditions will increase the core excess of a reactor?

a. Fuel depletion.

b. Burnout of a burnable poison.

c. Insertion of a negative reactivity worth experiment.

d. Higher moderator temperature (assume negative temperature coefficient).

QUESTION A.14 [1.0 point]

The following figure represents the differential rod worth of a reactor core. Based on this figure, which of the following statements BEST describes the characteristic of differential rod worth in the core?

a. The amount of reactivity per inch of travel is greatest at the bottom of the core because the rods have the greatest amount of worth in this region.

b. The amount of reactivity per inch of travel is the greatest in the center of the core is greatest because the neutron flux is greatest in this region.

c. As the rods approach the top of the core the reactivity effects become greater and the change in rod worth per inch of travel becomes greater.

d. The reactivity at the center of the core is where the differential rod worth is greatest and varies significantly with rod motion.

QUESTION A.15 [1.0 point]

You are performing a 50 Watt Critical Rod Position. Given the following data listed in the table below, calculate the SHUTDOWN MARGIN, as defined by Technical Specifications, given a clean, cold reactor core condition.

Core Reactivity Evaluation Data Control Rod Total Worth Critical Worth Transient $2.91 $1.63 Safety $4.04 $2.33 Shim $2.69 $1.51 Regulating $3.04 $1.70

a. $1.31

b. $2.92

c. $3.13

d. $5.79 QUESTION A.16 [1.0 point]

A reactor has been operating at full power for one week when a scram occurs. Twelve hours later, the reactor is brought critical and quickly raised to full power. Considering xenon effects only, to maintain a constant power level for the next few hours, control rods must be:

a. Inserted.

b. maintained at the present position.

c. Withdrawn.

d. withdrawn, then inserted to the original position.

QUESTION A.17 [1.0 point]

The reactor is operating at 100 KW. The reactor operator withdraws the regulating rod allowing power to increase. The operator then inserts the same rod to its original position, decreasing power. In comparison to the period due to the rod withdrawal, what will be the period due to the rod insertion?

The period due to the rod insertion will be

a. longer due to long lived delayed neutron precursors.

b. shorter due to long lived delayed neutron precursors.

c. same due to equal amounts of reactivity being added.

d. same due to equal reactivity rates from the rod.

QUESTION A.18 [1.0 point]

The count rate is 50 cps. An experimenter inserts an experiment into the core, and the count rate decreases to 25 cps. Given the initial Keff of the reactor was 0.8, what is the worth of the experiment?

a. = - 0.42

b. = + 0.42

c. = - 0.21

d. = + 0.21 QUESTION A.19 [1.0 point]

A reactor startup is in progress. Each control rod withdrawal is inserting exactly EQUAL amounts of reactivity. Select the EXPECTED neutron population and count rate response as "Keff" approaches 1.0.

The change in neutron population per reactivity insertion is:

a. SMALLER, and it takes LESS time to reach a new equilibrium count rate.

b. LARGER, and it takes LESS time to reach a new equilibrium count rate.

c. SMALLER, and it takes MORE time to reach a new equilibrium count rate.

d. LARGER, and it takes MORE time to reach a new equilibrium count rate.

QUESTION A.20 [1.0 point]

A reactor contains a neutron source that produces 10,000 neutrons/second. The reactor has a keff = 0.92. 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

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

QUESTION B.01 [1.0 point]

Which ONE of the following is NOT a responsibility of the SRO and RO?

a. Review and audit of safety aspects of reactor facility operations

b. Insertion and removal of experiments

c. Participation in requalification program

d. Preparation of logs and records of reactor operations QUESTION B.02 [1.0 point]

If you are NOT active watchstander, by the regulation 10CFR55.53(e), how many hours of licensed RO or SRO activity must you perform to become current?

a. 2

b. 4

c. 6

d. 8 QUESTION B.03 [1.0 point]

To minimize radiation effects, SOP-1 prohibits the reactor operation shall not be closer than

________ to the pool divider walls.

a. 1 foot

b. 2 feet

c. 3 feet

d. 4 feet QUESTION B.04 [1.0 point]

Who MUST inspect the rabbit sample prior inserting the rabbit sample into the pneumatic transfer system?

a. the reactor operator.

b. the Health Physics office.

c. the experimenter.

d. the senior reactor operator.

QUESTION B.05 [1.0 point]

AP-1 requires a licensed operator and a licensed senior reactor operator present at the facility whenever the reactor is not secured. Which of the following areas meets the definition of the facility?

a. The reactor pool and control room.

b. The reactor pool, the control room, and all adjacent laboratories.

c. The entire PSBR building.

d. All areas within the facility perimeter fence.

QUESTION B.06 [1.0 point]

Per SOP-1, when performing a PULSE operation, the MINIMUM limit of reactivity is ______.

a. $1.00

b. $1.50

c. $2.50

d. $3.00 QUESTION B.07 [1.0 point]

In the event of an emergency involving an emergency evacuation, the Duty RO is responsible to:

a. be a member of the re-entry team and reporting to the Emergency Director.

b. be the acting Emergency Director until relieved by higher levels of facility management.

c. admit appropriate emergency support personnel to the facility to mitigate the consequences of the emergency.

d. open and take charge of the Emergency Support Center, distributing emergency equipment to appropriate support personnel.

QUESTION B.08 [1.0 point]

Which of the following demonstrates the most correct example of a contamination survey?

a. Using an ion chamber detector to verify the posting requirements of a high radiation area.

b. Using a neutron detector (i.e., neutron ball) to determine if levels at the beam cave entrance permit entry.

c. Using a Geiger-Mueller detector on a dry mop to determine if activation levels are greater than the minimum detectable.

d. Using a high purity germanium detector to characterize peak profiles of a sample for neutron activation analysis.

QUESTION B.09 [1.0 point]

Per PSBR Technical Specifications, the safety system channels required to be operable in all modes of operation are:

a. Fuel temperature, High Power, Detector Power Supply.

b. Fuel temperature scram, Scram Button Console, Watchdog Circuit.

c. High Power, Detector Power Supply, Preset Timer.

d. Source level, Pulse Mode Inhibit, Transient Rod.

QUESTION B.10 [1.0 point]

Which one of the following meets the definition of Safety Limit?

a. Setting for an automatic protective device related to a variable having a significant safety function.

b. Limits on important process variables to protect the fuel element cladding.

c. Limits imposed on reactor core reactivity for a reference core condition.

d. Constraints included in the Technical Specifications that are required for safe operation of the facility.

QUESTION B.11 [1.0 point]

You are a reactor operator at PSBR and handling irradiated samples in accordance with PSBR procedures and precautions. One of the irradiated sample you pull directly from the core measures 100 Rem/hr at 1 meter. If you moved 10 meters away, how long would you have to wait before you would exceed your occupational whole-body dose (i.e., TEDE) limit for radiation exposure?

a. 0.5 hr.

b. 1 hr.

c. 2 hrs.

d. 5 hrs.

QUESTION B.12 [1.0 point]

Which ONE of the following is the main contributor to Ar-41 production at PSBR?

a. Neutron interaction with the D2O tank.

b. Neutron interaction with the oxygen in the reactor pool water.

c. Pool water evaporation

d. Neutron interaction with dissolved air in the reactor pool water QUESTION B.13 [1.0 point]

Which ONE of the following are the potential sources of airborne radioactive material release at PSBR?

a. A loss of coolant accident, and the reactivity insertion accident.

b. A loss of coolant accident, and a rupture of one or more fuel elements.

c. The reactivity insertion accident, and leakage or rupture of an irradiated sample or experimental apparatus.

d. A rupture of one or more fuel elements, and leakage or rupture of an irradiated sample or experimental apparatus.

QUESTION B.14 [1.0 point]

A radioactive source reads 4 Rem/hr on contact. Two hours later, the same source reads 1 Rem/hr. How long is the time for the source to decay from a reading of 4 Rem/hr to 20 mRem/hr?

a. 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />

b. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />

c. 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />

d. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> QUESTION B.15 [1.0 point, 0.25 each]

Identify each of the following surveillances as a channel check (CHECK), a channel test (TEST), or a channel calibration (CAL)? (Write the answer next to each a, b, c, d in the answer sheet)

a. Adjust the Wide Range Linear Power Channel in accordance with recent data collected on the reactor thermal power calibration.

b. Verify the reactor interlock system by removing the neutron source away from the reactor core.

c. Compare readings of area radiation monitors during a reactor operation.

d. Verify a fuel temperature scram during the checkout.

QUESTION B.16 [1.0 point]

A building evacuation alarm has just sounded. Where would you expect most people to muster IMMEDIATELY after acknowledging the alarm and need to evacuate from PSBR?

a. Reactor Bay

b. PSBR Lobby

c. Neutron Beam Lab

d. Main Gate QUESTION B.17 [1.0 point, 0.25 each]

Match the radiation reading from Column A with its corresponding radiation area classification (per 10 CFR 20) listed in Column B. Answer in Column B can be used more than once, or not at all. Assume that the source can be a point source.

Column A Column B

a. 2 mrem/hr at 1 m 1. Public Area

b. 20 mrem/hr at 1 m 2. Radiation Area

c. 50 mrem/hr at 1 m 3. High Radiation Area

d. 5.5 grays/hr at 1 m 4. Very High Radiation Area QUESTION B.18 [1.0 point]

Which one of the following is the 10 CFR 20 definition of total effective dose equivalent (TEDE) ?

a. The sum of the deep dose equivalent and the committed effective dose equivalent.

b. The dose that your whole body receives from sources outside the body.

c. The sum of the external deep dose and the organ dose.

d. The dose to a specific organ or tissue resulting from an intake of radioactive material.

QUESTION B.19 [1.0 point]

A release of airborne radioactive material where a person at the reactor site boundary is expected to receive a deep dose equivalent of 15 mrem over a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period is classified as:

a. Unusual Event.

b. Alert.

c. Site Area Emergency.

d. General Emergency.

QUESTION B.20 [1.0 point]

According to AP-1, which of the following activities DOES NOT require an operating license?

a. A student operating the reactor controls as part of a planned facility tour.

b. An intern participating in a control rod inspection surveillance under the supervision of a licensed reactor operator.

c. A summer hire handling and removing a fuel element from the reactor core under the supervision of a licensed senior reactor operator.

d. Authorize a deviation from Technical Specifications in accordance with 10 CFR 50.54 (x).

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

QUESTION C.01 [1.0 point]

Which ONE of the following best describes the status of the control rods in the 2 Rod Auto mode?

a. Shim and transient rods banked for automatic control and the safety rod shimmed.

b. Shim and regulating rods banked for automatic control and the safety rod shimmed.

c. Regulating and safety rods banked for automatic control and the shim rod shimmed.

d. Regulating, shim, and safety rods banked for automatic control and no shimming rod.

QUESTION C.02 [1.0 point]

Which ONE of the followings controls the amount of reactivity that is inserted by the transient rod during pulse operations?

a. The preset pulse timer setting that vents the pneumatic piston.

b. The steady state power of the reactor prior to firing the pulse.

c. The pressure of the air applied to the pneumatic piston.

d. The position of the cylinder.

QUESTION C.03 [1.0 point]

Which ONE of the following will initiate a reactor step back?

a. Pool outlet conductivity is low.

b. Reactor key is on.

c. Fuel temperature is high.

d. Facility exhaust is off.

QUESTION C.04 [1.0 point]

Which of the following nuclides does the carbon filter have a high efficiency for removal when it is in service?

a. N-16

b. Ar-41

c. Co-60

d. I-131 QUESTION C.05 [1.0 point]

Reclaimed water from the Liquid Waste Evaporator System is transferred to the reactor pool as makeup water by the ________.

a. makeup pump

b. process water pump

c. distillate pump

d. storage tank transfer pump QUESTION C.06 [1.0 point]

Which ONE of the following is the MAIN purpose for setting a conductivity limit of the pool water?

a. To minimize the possibility of corrosion of fuel cladding and other primary system components.

b. To maintain the departure of nucleate boiling ratio (DNBR) greater than the unity.

c. To extend integrity of resin bed on the demineralizer.

d. To minimize Ar-41 released to the public.

QUESTION C.07 [1.0 point]

Which ONE of the following best describes the purpose of DCC-X bulk pool temperature alarm?

The DCC-X bulk pool temperature alarm is set at ~ 35°C/100°F to ensure that:

a. the resin in the demineralizer is not damaged.

b. nucleate boiling does not occur on fuel element surfaces.

c. there is an adequate heat sink for the full thermal power of the reactor.

d. the expansion of pool water at higher temperatures does not reduce the moderating capability of the coolant.

QUESTION C.08 [1.0 point]

Which ONE of the followings describes an RSS operational interlock function while in the pulse mode of operation?

a. Prevents manual withdrawal of any rod.

b. Prevents manual withdrawal of more than one rod.

c. Prevents movement of all rods except the transient rod.

d. Prevents application of air to the transient rod if the drive is not fully down.

QUESTION C.09 [1.0 point]

After the ventilation systems have switched modes during Evacuation Initiation, which of the following is the MOST POSITIVE indication that the Emergency Ventilation system has flow?

a. All control rods have scrammed and all rod bottom lights are indicating DOWN.

b. A DCC-X message Emergency Ventilation Flow On displays on the reactor console.

c. When the louvers of the facility exhaust fans close there will be an East and West Fans Off message on DCC-X.

d. A red power-on light on the Cobalt-60 lobby control panel turns on, as does a red pilot light on the circuit box on the east wall of the reactor bay.

QUESTION C.10 [1.0 point]

Which ONE of the followings BEST describes the purpose of the bottom reactor grid plate?

a. It supports the weight of the fuel.

b. It supports the weight of the control rods.

c. It permits insertion of wire for in-core measuring purpose.

d. It has a central thimble with a 1.33" inside diameter to facilitate the irradiation of large in-core experiments.

QUESTION C.11 [1.0 point]

When will the Emergency Exhaust System be activated?

a. Emergency Exhaust System is activated when the facility exhaust system is secured.

b. Emergency Exhaust System is activated whenever a building evacuation alarm is initiated.

c. Emergency Exhaust System is activated when the pressure drop across the facility exhaust system filters doubles.

d. Emergency Exhaust System is activated when the reactor bay has a positive pressure with respect to the atmosphere.

QUESTION C.12 [1.0 point]

Which ONE of the following systems provide all operational interlocks and safety trips required by technical specifications?

a. Reactor safety system (RSS).

b. Digital Control Computer (DCC-Z).

c. Digital Control Computer (DCC-X).

d. Protection, control and monitoring system (PCMS).

QUESTION C.13 [1.0 point]

Which ONE of the following radiation monitoring systems will NOT activate the emergency evacuation alarm upon receipt of a high radiation alarm?

a. Reactor pump room.

b. Reactor bay air west.

c. Beam laboratory.

d. Co60 bay.

QUESTION C.14 [1.0 point]

The output of the ________ is always proportional to the neutron population in the core regardless of the power level.

a. Pulse Power Monitor

b. Power Range Monitor

c. Wide Range Monitor

d. Instrumented Fuel Element QUESTION C.15 [1.0 point]

The figure below is an example of the gas ionization curve for gas-filled detectors.

Which ONE of the following curve regions (in roman numbers) corresponds to the Geiger-Mueller region?

a. Region II.

b. Region III.

c. Region IV.

d. Region V.

QUESTION C.16 [1.0 point]

Which ONE of the following conditions will prevent applying air to the Transient Rod (TR) system due to TR air interlock?

a. Pool temperature exceeds 40 °C.

b. In pulse mode and initial power low (200 W).

c. Air has previously been applied (permissive latch).

d. In steady state mode and transient rod drive at its top of travel.

QUESTION C.17 [1.0 point]

PSBR has what is known as a prompt negative temperature coefficient associated with the fuel in the core. As the homogenous fuel-moderator mixture heats up, the total reactivity of the core decreases. Which of the following is NOT considered a contributing factor to the prompt negative temperature coefficient during a pulse?

a. There is a Doppler effect which causes the broadening of epithermal cross-section resonance peaks for U-238, thereby decreasing the probability of resonance escape.

b. As temperature increases, the fission cross-section for U-235 decreases, thereby increasing the amount of leakage from the core.

c. Hydrogen atoms impart kinetic energy to neutrons (i.e., upscattering), thereby reducing the fission cross-section.

d. The moderator is heated up and there are more neutrons at higher energies, the result is a higher leakage of neutrons from the core.

QUESTION C.18 [1.0 point]

Which one of the followings is MOST correct statement?

Regarding experimental apparatus setup at PSBR, a gamma shield is located at a 45- degree angle to the D2O tank collimator tube in order to ________.

a. minimize streaming core gammas from entering the collimator tube

b. minimize the positive reactivity excursion that could exceed PSBR TS when the core is in the D2O position

c. allow the maximum amount of heat transfer between the core and the collimator tube when the core is in the D2O position

d. reduce the amount of fast neutron embrittlement to the steel structure components on the experiment bridge and the pool wall when the core is in the D2O position QUESTION C.19 [1.0 point]

You are performing a radiation survey around the reactor pool using a Geiger Mueller detector.

Which of the following is a disadvantage of using this type of detector?

a. It is sensitive to light.

b. It is unable to electronically discriminate different types of radiation.

c. It has a separate alpha and beta plateau curve which must be accounted for.

d. It has a short resolving time when detecting radiation.

QUESTION C.20 [1.0 point]

According to PSBR SOP-1 pulses shall be initiated from a stable 100W with balanced rods to

a. ensure repeatability and facilitate the comparison of pulsing results

b. prevent exceeding the maximum pulse limit of 2000 MW

c. allow enough time to start-up the reactor

d. position the Transient rod cylinder

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

((***** END OF EXAM *****))

A.01 Answer: d

Reference:

DOE Handbook Nuclear Physics & Reactor Theory, Volume 1, Module 2, pg. 9 A.02 Answer: a

Reference:

PSBR Training Manual Chapter 2.1.1 Alpha Particle Interactions with Matter A.03 Answer: b

Reference:

DOE Handbook, Fundamentals of Nuclear Engineering, Volume 1, Module 1, Prompt and Delayed Neutrons, pg. 29 A.04 Answer: b

Reference:

DOE Fundamentals Handbook Nuclear Physics and Reactor Theory Vol. 2, pg. 41 A.05 Answer: a

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, © 1988 pg. 2-63.

A.06 Answer: a

Reference:

PSBR Training Manual Chapter 3, A.5 Operation of Reactor Against D2O Tank.

A.07 Answer: d

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, © 1988 pg. 3-4.

A.08 Answer: c

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, © 1988 pg. 6-1.

A.09 Answer: d

Reference:

DOE Handbook Nuclear Physics & Reactor Theory, Vol. 2, Section Reactivity Coefficients and Reactivity Defect, pg. 21, = T*T = (-0.00082 pcm/oF) * (-

10oF) = 0.0082 k/k A.10 Answer: c

Reference:

P = P0 e-t/T = 1 kW

• e(120sec/-80sec) = 1 kW

• exp(-1.5) = 0.223

• 1 kW =

0.223 kW = 223 W A.11 Answer: d

Reference:

The power of reactor A increases by a factor of 2, while the power of reactor B increases by a factor of 1.25. Since the periods are the same (rate of change is the same), power increase B takes a shorter time.

A.12 Answer: a

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, pg. 3-21.

p = (Keff-1)/Keff = (0.955-1)/0.955 = -0.04712 k/k. Reactor needs 0.04712 k/k for reaching to critical, since 0.030 k/k < 0.04712 k/k, the reactor is still in subcritical.

A.13 Answer: b

Reference:

DOE Fundamentals Handbook Nuclear Physics and Reactor Theory Vol. 2, pg.

30.

A.14 Answer: b

Reference:

DOE Fundamentals Handbook Nuclear Physics and Reactor Theory Vol. 2, pg.

52.

A.15 Answer: c

Reference:

PSBR CL57 Core Eval & Rod Worth Data, (performed 09/09/2016)

SDM = Critical worth - Most reactive Rod worth remaining out of core SDM = ($1.63+2.33+1.51+1.70)-$4.04 = $3.13.

A.16 Answer: a

Reference:

PSBR Reactor Training Manual, Chapter 3 Reactor Physics and Operating Characteristics, Pages 69 through 72.

A.17 Answer: a

Reference:

PSBR Reactor Training Manual - Chapter 3 Reactor Physics and Operating Characteristics, pg. 101.

A.18 Answer: a

Reference:

CR1 / CR2 = (1 - Keff2) / (1 - Keff1) 50 / 25 = (1 - Keff2) / (1 - 0.8) Therefore Keff2 = 0.6

= Keff2 - Keff1 / Keff2

• Keff1 = (0.6 - 0.8)/(0.6

• 0.8) = - 0.41667 A.19 Answer: d

Reference:

PSBR Reactor Training Manual - Chapter 3 Reactor Physics and Operating Characteristics, pg. 93.

A.20 Answer: c

Reference:

DOE Fundamentals Handbook, Vol. 2, Module 4, EO 1.2, pg. 4 N = (S) (M)

M = 1 / (1-keff) = 1 / (1-0.92) = 12.5 N = (10,000)(12.5) = 125,000 neutrons/second B.01 Answer: a

Reference:

PSBR TS Section 6.2.

B.02 Answer: c

Reference:

10CFR55.53(e).

B.03 Answer: d

Reference:

PSBR SOP-1, Reactor Operating Procedure, pg. 27.

B.04 Answer: d

Reference:

PSBR SOP-9, pg. 2.

B.05 Answer: d

Reference:

PSBR AP-1 Personnel Requirements for Reactor Operations, pg. 1.

B.06 Answer: b

Reference:

PSBR SOP-1, pg. 12.

B.07 Answer a

Reference:

PSBR EP-1, pg. 5 B.08 Answer: c

Reference:

PSBR AOP-4, pg. 2.

B.09 Answer: b

Reference:

PSBR TS Section 3.2.4 (Table 2a).

B.10 Answer: b

Reference:

PSBR TS Section 1.1.36.

B.11 Answer: d

Reference:

10 CFR 20 (DR1)(R1)²= (DR2)(R2)² (100 R/hr)(1 m)² = (X) (10 m)² = 1 R/hr Occupational whole-body dose (i.e., TEDE) limit per 10 CFR 20= 5 Rem for The individual would have to stay in the area for 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> before they exceeded this dose limit.

B.12 Answer: d

Reference:

PSBR SAR Chapter 11, Section 11.1.1, pg. XI-1.

B.13 Answer: d

Reference:

PSBR EP-5,Section V.C. Sources of Airborne Radioactive Material Release.

B.14 Answer: b

Reference:

DR = DR*e -t 1 rem/hr =4 rem/hr* e -(2hr)

Ln(1/4) = -*2 --> =0.693; solve for t: Ln(.02/4)=-0.693 (t) t=7.6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

B.15 Answer: a = CAL; b = TEST; c = CHECK; d = TEST

Reference:

PSBR TS Section 1.1.

B.16 Answer: d

Reference:

PSBR EP-13 Building Evacuation, pg. 2.

B.17 Answer: a(2); b(3); c(3); d(4)

Reference:

10 CFR 20.1003 Definitions 2 mrem/hr at 1 m = 22.2 mrem/hr at 30 cm => Radiation area 50 mrem/hr at 1m = 0.55 rem/hr at 30 cm => high radiation area 20 mrem/hr at 1m = 222 mrem/hr at 30 cm :=> high radiation area 5.5 grays 550 rad/hr at 1 m very high radiation area. Definition High Radiation Area: 100 mrem/hr at 30 cm Radiation Area: 5 mrem/hr at 30 cm Very High Radiation Area: 500 rads/hr at 1 m.

B.18 Answer: a

Reference:

10 CFR 20.1003 Definitions.

B.19 Answer: a

Reference:

PSBR EP-5 Section V (G), pg. 4.

B.20 Answer: c

Reference:

PSBR SOP-1 Reactor Operating Procedure, pg. 2.

C.01 Answer: b

Reference:

PSBR SAR Section 7.3.1.1 Modes of Operation.

C.02 Answer: d

Reference:

PSBR Training Manual SOP-1 V.F. Pulse Operations.

C.03 Answer: c

Reference:

PSBR Training Manual Chapter 4 Section 4.2.9.1bi.

C.04 Answer: d

Reference:

PSBR Training Manual Chapter 5.3.4.1 Emergency Exhaust System.

C.05 Answer b

Reference:

PSBR Training Manual, Chapter 5 Section 5.2.3.2 Processed Water System.

C.06 Answer: a

Reference:

PSBR TS Section 3.3.5.

C.07 Answer: a

Reference:

PSBR Training Manual, Chapter 5.2.3.1 Demineralizer and T.S. Section 3.3.6.

C.08 Answer: c

Reference:

PSBR Training Manual, Section 4.2.5.

C.09 Answer: b

Reference:

PSBR Training Manual Chapter 5, Section 5.3.4.3 EES Function During an Evacuation Initiation.

C.10 Answer: a

Reference:

PSBR SAR, Chapter 4, Section 4.2.5, pg. IV-18.

C.11 Answer: b

Reference:

PSBR Training Manual, Chapter 5, Section 5.3.4.1.

C.12 Answer: a

Reference:

PSBR Training Manual Chapter 4 Section 4.2, Pg. 26.

C.13 Answer: a

Reference:

PSBR SAR Section 7.7, PSBR Training Manual Chapter Section 4 4.1.13 Hot Cells and Pump Room Monitors.

C.14 Answer: c

Reference:

PSBR Training Manual, Chapter 3, A.3.

C.15 Answer: d

Reference:

PSBR Training Manual, Chapter 4 Instrumentation and Control & Radiation Detection , Figure 4.1.

C.16 Answer: d

Reference:

SAR 7.4.3 C.17 Answer: b

Reference:

PSBR Training Manual Chapter 3 Appendix A.10.

C.18 Answer: a

Reference:

PSBR Training Manual, Chapter 5 Facility Design & Emergency Systems, Section 5.4.2, pg. 62.

C.19 Answer: b

Reference:

PSBR Training Manual Chapter 4 Instrumentation and Control & Radiation Detection , pg. 5.

C.20 Answer: a

Reference:

PSBR SOP-1,Section V.F. Pulse Operations, pg. 12