ML021330702
| ML021330702 | |
| Person / Time | |
|---|---|
| Site: | National Bureau of Standards Reactor |
| Issue date: | 05/22/2002 |
| From: | Madden P NRC/NRR/DRIP/RORP |
| To: | Rowe J US Dept of Commerce, National Institute of Standards & Technology (NIST) |
| Doyle P, NRC/NRR/DRIP/RORP, 415-1058 | |
| Shared Package | |
| ML021330811 | List: |
| References | |
| 50-184/OL-02-01 50-184/OL-02-01 | |
| Download: ML021330702 (37) | |
Text
May 22, 2002 Dr. J. Michael Rowe, Director NIST Center for Neutron Research National Institute of Standards and Technology U. S. Department of Commerce Gaithersburg, MD 20899
SUBJECT:
INITIAL EXAMINATION REPORT NO. 50-184/OL-02-01, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY
Dear Dr. Rowe:
On March 1 and April 19, 2002, the NRC administered operator licensing examinations at your National Institute of Standards and Technology Reactor. The examinations were conducted according to NUREG-1478, "Non-Power Reactor Operator Licensing Examiner Standards," Revision 1. 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 10 CFR 2.790 of the Commissions regulations, 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 NRCs document system (ADAMS). ADAMS is accessible from the NRC Web site at (the Public Electronic Reading Room) http://www.nrc.gov/NRC/ADAMS/indesx.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 Paul Doyle at (301) 415-1058 or via E-mail at pvd@nrc.gov.
Sincerely,
/RA by Marvin Mendonca Acting for/
Patrick M. Madden, Section Chief Research and Test Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs
Office of Nuclear Reactor Regulation Docket No. 50-184
Enclosures:
- 1. Initial Examination Report No. 50-184/OL-02-01
- 2. Facility comments with NRC resolution
- 3. Examination and answer key (RO/SRO) cc w/encls: Please see next page
National Institute of Standards Docket No. 50-184 and Technology cc:
Montgomery County Executive County Office Building Rockville, MD 20858 Director Department of State Planning 301 West Preston Street Baltimore, MD 21201 Director Department of Natural Resources Power Plant Siting Program Energy and Coastal Zone Administration Tawes State Office Building Annapolis, MD 21401 Dr. Seymour H. Weiss, Chief Reactor Operations and Engineering National Institute of Standards and Technology U.S. Department of Commerce Gaithersburg, MD 20899 Honorable Michael L. Subin Montgomery County Council Stella B. Werner Council Office Building Rockville, MD 20850 Dr. William Vernetson Director of Nuclear Facilities Department of Nuclear
Engineering Sciences University of Florida Gainesville, FL 32611-8300 Mr. Jim Torrence Reactor Radiation Division National Institute of Standards and Technology U.S. Department of Commerce Gaithersburg, MD 20899
May 22, 2002 Dr. J. Michael Rowe, Director NIST Center for Neutron Research National Institute of Standards and Technology U. S. Department of Commerce Gaithersburg, MD 20899
SUBJECT:
INITIAL EXAMINATION REPORT NO. 50-184/OL-02-01, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY
Dear Dr. Rowe:
On March 1 and April 19, 2002, the NRC administered operator licensing examinations at your National Institute of Standards and Technology Reactor. The examinations were conducted according to NUREG-1478, "Non-Power Reactor Operator Licensing Examiner Standards," Revision 1. 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 10 CFR 2.790 of the Commissions regulations, 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 NRCs document system (ADAMS). ADAMS is accessible from the NRC Web site at (the Public Electronic Reading Room) http://www.nrc.gov/NRC/ADAMS/indesx.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 Paul Doyle at (301) 415-1058 or via E-mail at pvd@nrc.gov.
Sincerely,
/RA by Marvin Mendonca Acting for/
Patrick M. Madden, Section Chief Research and Test Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket No. 50-184
Enclosures:
- 1. Initial Examination Report No. 50-184/OL-02-01
- 2. Examination and answer key cc w/encls: Please see next page
DISTRIBUTION w/ encls.:
PUBLIC RORP/R&TR r/f PMadden TDragoun, RI MMendonca Facility File (EBarnhill) O6-D17 ADAMS ACCESSION #: ML021330702 TEMPLATE #:NRR-074 OFFICE RORP:CE IEHB:LA E RORP:SC NAME PDoyle EBarnhill PMadden DATE 05/ 14 /2002 05/ 17 /2002 05/ 21 /2002 C = COVER E = COVER & ENCLOSURE N = NO COPY OFFICIAL RECORD COPY
U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-184/OL-02-01 FACILITY DOCKET NO.: 50-184 FACILITY LICENSE NO.: TR-5 FACILITY: National Institute of Standards and Technology EXAMINATION DATES: March 1, 2002 and April 19, 2002 SUBMITTED BY: __________/RA/__________________ 05/07/2002 Paul Doyle, Chief Examiner Date
SUMMARY
On March 1, 2002, the NRC administered written examinations to two Senior Operator license candidates for the National Institute of Standards and Technology Reactor. On April 19, 2002 the NRC administered operating tests to the two Senior Operator license candidates.
REPORT DETAILS
- 1. Examiners:
Paul Doyle, Chief Examiner
- 2. Results:
RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 0/0 2/0 2/0 Operating Tests 0/0 2/0 2/0
Overall 0/0 2/0 2/0
- 3. Exit Meeting:
Paul Doyle, NRC, Chief Examiner Seymour Weiss, NIST, Chief, Reactor Operations and Engineering During the exit meeting the examiner thanked the facility for their support of the operating tests. The examiner stated that he did NOT notice any generic weaknesses on the part of the candidates.
ENCLOSURE 1
National Institute of Standards and Technology With Answer Key
OPERATOR LICENSING EXAMINATION March 1, 2002 Enclosure 2
Section A / Theory, Thermo & Fac. Operating Characteristics Page 11 QUESTION A.1 [1.0 point]
Inserting a shim arm predominantly affects Keff by changing the
- a. fast fission factor
- b. thermal utilization factor
- c. neutron reproduction factor
- d. resonance escape probability.
QUESTION A.2 [1.0 point]
You enter the control room and note that ALL nuclear instrumentation show a STEADY NEUTRON LEVEL, and no rods are in motion.
Which ONE of the following conditions CANNOT be true?
- a. The reactor is critical.
- b. The reactor is sub-critical.
- c. The reactor is super-critical.
- d. The neutron source has been removed from the core.
QUESTION A.3 [1.0 point]
The neutron microscopic cross-section for absorption a generally
- a. increases as neutron energy increases.
- b. decreases as neutron energy increases.
- c. increases as the mass of the target nucleus increases.
- d. decreases as the mass of the target nucleus increases.
Section A / Theory, Thermo & Fac. Operating Characteristics Page 12 QUESTION A.4 [1.0 point]
Which ONE of the four listed factors (of the six-factor formula) is greater than one for the NIST reactor?
- a. Fast Fission Factor ( )
- b. Thermal Utilization Factor (f)
- c. Thermal Non-Leakage probability (üth)
- d. Resonance Escape probability (p)
QUESTION A.5 [1.0 point]
Which one of the following is the correct reason that delayed neutrons allow human control of the reactor?
- a. More delayed neutrons are produced than prompt neutrons.
- b. Delayed neutrons increase the mean neutron lifetime.
- c. Delayed neutrons take longer to thermalize than prompt neutrons.
- d. Delayed neutrons are born at higher energies than prompt neutrons.
QUESTION A.6 [2.0 points, 1/2 each]
Match type of radiation (Column A) with the proper penetrating power (Column B).
- a. Gamma 1. Stopped by thin sheet of paper
- b. Beta 2. Stopped by thin sheet of metal
- c. Alpha 3. Best shielded by light (low-z) material
- d. Neutron 4. Best shielded by heavy (high-z) material
Section A / Theory, Thermo & Fac. Operating Characteristics Page 13 QUESTION A.7 [1.0 point]
Which one of the following figures most closely depicts the reactivity versus time plot for xenon for the following series of evolutions: (See attached figures on last page of handout for choice selections.) TIME EVOLUTION 1 10 MW startup, clean core 2 Reduce power operate at 5 MW 3 Shutdown 4 Restart reactor operate at 5 Mw.
- a. Figure a
- b. Figure b
- c. Figure c
- d. Figure d QUESTION A.8 [1.0 point]
Using the Integral Rod Worth Curve provided identify which ONE of the following represents Kexcess
- a. Area under curve B.
- b. C
- c. max - C
- d. Areas under curve A & B QUESTION A.9 [1.0 point]
Given that the NBSR is shutdown with a Keff of 0.84, and eff is 0.008. Calculate the amount of reactivity required to achieve criticality.
- a. 12.8$
- b. 16$
- c. 24$
- d. 30$
Section A / Theory, Thermo & Fac. Operating Characteristics Page 14 QUESTION A.10 [1.0 point]
To calibrate the shim arms, you measure doubling time then calculate period. If the doubling time was 42 seconds, which ONE of the following is the period?
- a. 29 seconds
- b. 42 seconds
- c. 61 seconds
- d. 84 seconds QUESTION A.11 [1.0 point]
Given secondary flow through HE-1A & B is 9650gpm, HE-1A & 1B (Secondary Inlet Temperature) both read 80EF, HE-1A &1B secondary Outlet Temperature both read 91EF, and the Thermal Power constants for water is 147 watts/gpm-EF (H2O), determine the current operating power.
- a. 78%
- b. 71%
- c. 65%
- d. 59%
Section A / Theory, Thermo & Fac. Operating Characteristics Page 15 QUESTION A.12 [1.0 point]
Which ONE of the following is the correct definition of effective ? The relative amount of delayed neutrons compared to the total number of neutrons
- a. per generation.
- b. per generation corrected for leakage.
- c. per generation corrected for time after the fission event.
- d. per generation corrected for both leakage and time after the fission event.
QUESTION A.13 [1.0 point]
Which ONE of the following reactor changes require a control rod INSERTION to return reactor power to its initial level following the change?
- a. Formation of N16 in the coolant.
- b. Removal of an experiment with positive reactivity from the reactor.
- c. Buildup of Xe135
- d. A fault in the automatic system resulting in a primary coolant temperature decrease.
QUESTION A.14 [1.0 point]
Which ONE of the following is the reason that Xenon Peaks after a shutdown?
- b. Promethium decays faster than Xenon decays
- d. Xenon decays faster than Promethium
Section A / Theory, Thermo & Fac. Operating Characteristics Page 16 QUESTION A.15 [1.0 point]
The number of neutrons passing through a one square centimeter of target material per second is the definition of which one of the following?
- a. Neutron Population (np)
- b. Neutron Impact Potential (nip)
- c. Neutron Flux (nv)
- d. Neutron Density (nd)
QUESTION A.16 [1.0 point]
Shown below is a trace of reactor period as a function of time. Between points A and B reactor power is:
- a. continually increasing.
- b. continually decreasing.
- c. increasing, then decreasing.
- d. constant.
Section A / Theory, Thermo & Fac. Operating Characteristics Page 17 QUESTION A.17 [1.0 point]
Which ONE of the following factors is the most significant in determining the differential worth of a control rod?
- a. The rod speed.
- b. Reactor power.
- c. The flux shape.
- d. The amount of fuel in the core.
QUESTION A.18 [1.0 point]
To make a just critical reactor PROMPT CRITICAL, by definition you must add reactivity equal to
- a. eff
- b. eff
- c. eff
- d. Keff QUESTION A.19 [1.0 point]
Keff is K4 times the
- a. fast fission factor ( )
- b. reproduction factor ( )
- c. total non-leakage factor (üf x üth)
- d. resonance escape probability (p)
Section B Normal/Emergency Procedures & Radiological Controls Page 18 QUESTION B.1 [1.0 point]
Youve detected a stuck regulating rod. Which ONE of the following is your immediate action(s) according to Annunciator Instruction 0.3?
- a. Attempt to drive the regulating rod in until power decreases by 2%.
- b. Drive all shim arms in verifying the stuck regulating rod fails to move.
- c. Scram the reactor, noting the position of the stuck rod.
- d. Control reactor power using the shim arms.
QUESTION B.2 [1.0 point]
Which ONE of the following Reactor Run-Downs is REQUIRED by Technical Specifications?
- a. High Thermal Power (BTUR)
- b. High Reactor Outlet Temperature
- c. Low Reactor Vessel Level.
- d. Low Thermal Shield Cooling System Flow.
QUESTION B.3 [1.0 point]
ANNUAL maintenance was last performed on a system on July 31, 2001. The last date annual maintenance may be performed on the system without being late is
- a. July 31, 2002
- b. August 31, 2002
- c. September 30, 2002
- d. October 31, 2002
Section B Normal/Emergency Procedures & Radiological Controls Page 19 QUESTION B.4 [2.0 points, 0.5 each]
Identify the source (Irradiation of Air, Coolant (D2O) or Fission Product (FP)) for each of the radioisotopes listed below.
- a. Xe135
- b. Ar41
- c. N16
- d. H3 QUESTION B.5 [2.0 points, 1/2 point each]
Match each of the Technical Specification Limits in column A with its corresponding value in column B. (Each limit has only one answer, values in Column B may be used more once, more than once or not at all.)
Column A Column B
- a. Minimum negative reactivity added by moderator dump 15%
- b. Absolute worth of any individual experiment 4.0%
- c. Maximum Core Excess Reactivity 2.6%
- d. The sum of the absolute Value of all experiments 1.0%
0.5%
Section B Normal/Emergency Procedures & Radiological Controls Page 20 QUESTION B.6 [2.0 points, 1/2 each]
Identify each of the following Technical Specification Requirements as being either a Safety Limit (SL) Limiting Safety System Setting (LSSS) or a Limiting Condition for Operation (LCO).
- a. Minimum Coolant Flow (inner plenum) 60 gpm/MW
- b. The reactor may be operated at power levels of up to 10 kW with reduced flow (including no flow) if decay heat is insufficient to cause significant heating of the reactor coolant.
- c. The reactor shall not be operated unless at least one shutdown cooling pump is operable.
QUESTION B.7 [1.0 point]
According to the Administrative Rules, the MINIMUM number of nuclear instruments required for refueling is
- a. one on-scale instrument with trip safety function
- b. two on-scale instruments with trip safety function
- c. one on-scale instrument
- d. two on-scale instruments QUESTION B.8 [1.0 point]
Although Tritium (H3) has a radioactive half-life of 12 years, the relative damage to the body is less than many other radioisotopes with this long a half-life because
- a. it is a beta emitter.
- b. it has a short (12 day) biological half-life.
- c. it is not readily absorbed by the body.
- d. it is an alpha emitter.
Section B Normal/Emergency Procedures & Radiological Controls Page 21 QUESTION B.9 [1.0 point]
Rescue personnel, are authorized to receive a pre-established radiation exposure WITHOUT Emergency Director (ED) approval in order to save someones life. Assuming rescue personnel have reached this limit, how much ADDITIONAL radiation exposure can the ED authorize for LIFESAVING ACTIONS during that same emergency?
- a. 25
- b. 50
- c. 75
- d. 100 Rem QUESTION B.10 [1.0 point]
Which ONE of the following experiments does NOT require double encapsulation or a doubled walled container?
- a. Fueled Experiment
- b. Explosive experiment
- c. Material corrosive to reactor
- d. Material corrosive to experimental coolant QUESTION B.11 [1.0 point]
A radiation survey instrument was used to measure an irradiated experiment. The results were 100 mrem/hr with the window open and 60 mrem/hr with the window closed. What was the beta dose?
- a. 40 mrem/hr
- b. 60 mrem/hr
- c. 100 mrem/hr
- d. 140 mrem/hr
Section B Normal/Emergency Procedures & Radiological Controls Page 22 QUESTION B.12 [1.0 point]
Which ONE of the following correctly completes the sentence. While the reactor is OPERATING, the process test switch may be placed in the "2 of 2" position
- a. for not longer than 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to allow the checking of a channel's operability.
- b. indefinitely if power is reduced below 10 MW before changing the selector's position.
- c. up to a maximum of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if no experiments are inserted into the reactor.
- d. while maintaining a steady power level but must be returned to the "1 of 2" position prior to changing power.
QUESTION B.13 [1.0 point]
A Radiation Work Permit (RWP) has been written to perform a non-repetitive task on potentially contaminated equipment. How long will this RWP remain in effect?
- a. Until the job is completed.
- b. 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> or until the end of the current shift.
- c. A maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
- d. Indefinitely, if reviewed daily by Health Physics.
Section B Normal/Emergency Procedures & Radiological Controls Page 23 QUESTION B.14 [1.0 point]
Per Annunciator Procedure 0.1 D2O System Rupture, Immediate Action, you would stop and isolate the shutdown cooling pumps and initiate top feed if vessel level falls below
- a. 60 inches.
- b. 100 inches.
- c. 140 inches.
- d. 180 inches.
QUESTION B.15 [1.0 point]
In regards to Emergency Health Physics Equipment located at the control room area, you would expect to find all of the following EXCEPT
- a. a personnel decontamination kit.
- b. portable emergency radios.
- c. protective clothing.
- d. Air Sampler QUESTION B.16 [1.0 point]
Which ONE of the following statements correctly defines the term "Channel Test?"
- a. The introduction of a signal into a channel and observation of the proper channel response.
- b. An arrangement of sensors, components and modules as required to provide a single trip or other output signal relating to a reactor or system operating parameter.
- c. The qualitative verification of acceptable performance by observation of channel behavior.
- d. The adjustment of a channel such that its output corresponds with acceptable accuracy to known values of the parameter which the channel measures.
Section B Normal/Emergency Procedures & Radiological Controls Page 24 QUESTION B.17 [1.0 point]
If estimated critical position differs from actual critical position by more than one degree you must:
- a. stop and recalculate the estimated critical position prior to further rod withdrawal.
- b. shut down the reactor.
- c. notify the Reactor Supervisor.
- d. notify the Chief Nuclear Engineer.
Section C Facility and Radiation Monitoring Systems Page 25 QUESTION C.1 [1.0 point, 1/4 point each]
Using the simplified diagram of the pneumatic tube (rabbit) system provided, identify the position of valves A through D (Open or Closed),
on a sample INSERTION.
- a. A
- b. B
- c. C
- d. D QUESTION C.2 [1.0 point]
A ventilation Radiation Monitor located on the B1 level is supplied with air drawn by a blower from 10 points within the ventilation system.
The primary purpose of this monitor is to monitor the concentration of
- a. H3
- b. Ar41
- c. Xe1331-135 (Fission Gases)
- d. N16 QUESTION C.3 [2.0 points, 1/2 each]
Match each type of gas listed with its correct purpose.
Gas Purpose
- a. Air 1. Gas used in the Pneumatic Tube (Rabbit) System.
- b. CO2 2. Used to operate ventilation system butterfly valves.
- c. N2 3. Cover gas on primary system to prevent loss of D2O.
- d. He 4. Backup to operate ventilation system butterfly valves.
Section C Facility and Radiation Monitoring Systems Page 26 QUESTION C.4 [1.0 point]
The MAIN purpose of the activated charcoal filters in the emergency exhaust systems is to absorb radioactive
- a. Tritium
- b. Iodine
- c. Argon
- d. Nitrogen QUESTION C.5 [2.0 points, 1/2 point each]
Identify the type of detector (B10 Proportional Counter (B10), Fission Counter (FC), Compensated Ion Chamber (CIC) or Uncompensated Ion Chamber(UIC)) utilized by each of the Nuclear Instrumentation channels listed below. (Note detector types may be used more than once or not at all.)
- a. Source Channels 1& 2
- b. Intermediate Range (Log-N) Channels 3 & 4
- c. Linear Power and Automatic Regulating Rod Control Channel 5
- d. Power Range Channels 6, 7 & 8.
QUESTION C.6 [1.0 point]
Which ONE of the following signals does NOT generate a MAJOR SCRAM?
- a. High Irradiated Air Monitor Activity Level
- b. High Normal Air Monitor Activity Level
- c. High Stack Monitor Activity Level
- d. High Fission Products Monitor Activity Level
Section C Facility and Radiation Monitoring Systems Page 27 QUESTION C.7 [1.0 point]
You discover several scratches on the outer plate of a fuel element. You inform the Reactor Supervisor who decides to use the element.
The decision to use this element was
- a. appropriate because the outer plates contain no fuel.
- b. appropriate because the outer two plates are thicker than the inner plates, due to thicker cladding.
- c. inappropriate because it could lead to fission product release from the plate due to reduced cladding.
- d. inappropriate because of the higher fuel loading of the outer plates.
QUESTION C.8 [1.0 point]
Following a major scram the ventilation system lineup
- a. must be reconfigured manually, the operator must start the dilution fan to maintain confinement pressure at no less than 0.25 inches negative.
- b. must be reconfigured manually, the operator must secure the normal ventilation and start the emergency exhaust system which maintains confinement pressure at no less than 0.25 inches negative.
- c. reconfigures automatically, the dilution fan energizes to maintain confinement pressure at no less than 0.25 inches negative.
- d. reconfigures automatically, normal ventilation secures, and the emergency exhaust system maintains confinement pressure at no less than 0.25 inches negative.
Section C Facility and Radiation Monitoring Systems Page 28 QUESTION C.9 [1.0 point]
Operation with the shim safety arms less than 12E is prohibited because
- a. the worth of the shim arms below this level is insignificant
- b. the scram spring force is insufficient to overcome shock absorber resistance.
- c. there is too much stress on the shim arm below this angle.
- d. the scram spring force is insufficient to overcome the pressure differential due to full core flow.
QUESTION C.10 [1.0 point]
Which ONE of the following is the material used as a neutron poison in the Regulating Rod?
- a. Erbium
- b. Cadmium
- c. Aluminum
- d. Boron QUESTION C.11 [2.0 points, 0.5 each]
Identify each of the essential electrical loads listed as being powered by AC Only (AC), DC Only, (DC) or AC or DC (AC/DC).
- a. Emergency Cooling Sump
- b. D2O Shutdown Pumps
- c. Emergency Exhaust Fans (EF 5 and EF 6)
- d. Annunciator Power and Evacuation Alarm
Section C Facility and Radiation Monitoring Systems Page 29 QUESTION C.12 [1.0 point]
Which ONE of the following Reactor Rundown Signals can NOT be bypassed?
- a. Cold Source flow
- b. Cold Source pressure
- c. Reactor Outlet Temperature
- d. Reactor Thermal Power.
QUESTION C.13 [1.0 point]
WHICH ONE of the listed components within the Helium Sweep Gas system is responsible for the recombination of disassociated D2 and O2?
- a. The 1/4 thick aluminum vessel containing alumina-palladium pellets.
- b. The 304 Stainless Steel cold Trap.
- c. The 1/4 aluminum plate tank containing an activated charcoal filter.
- d. The 6061 aluminum cylinder Gas Holder.
QUESTION C.14 [1.0 point]
Which ONE of the following is the method used to get rid of radioactive liquid waste? Radioactive liquid waste is sent to Health Physics where it is
- a. held, for decay of short lived isotopes then sampled for 10CFR20 limits and if satisfactory, pumped to the sewer system.
- b. put through evaporators, filters ion exchangers, reducing the liquid waste to proper solid form.
- c. diluted to less than 10CFR20 limits, then pumped to the sewer system.
- d. tested for 10CFR20 limits, then pumped to the sewer system.
Section C Facility and Radiation Monitoring Systems Page 30 QUESTION C.15 [1.0 point]
The Compensated Ion Chambers used at NIST do not have the compensating voltage connected. The reason that compensating voltage is not required in your reactor is because
- a. The Deuterium in the primary absorbs many gammas (gamma-neutron reaction).
- b. The Tritium in the primary absorbs many gammas (gamma-neutron reaction).
- c. There are lead windows located between the core and the detectors which absorb many gammas.
- d. A D2O moderated core must be larger than an H2O moderated core resulting in greater self-shielding of gammas.
QUESTION C.16 [1.0 point]
Identify each of the parts of the Thermal Column from the figure provided. (Note: Ignore cooling gap.)
Column A Column B
- a. A 1. Bismuth
- b. B 2. Boral
- c. C 3. D2O
- d. D 4. Graphite
- 5. H2O
Section A / Theory, Thermo & Fac. Operating Characteristics Page 31 A.1 b REF: Standard NRC Question1 A.2 c REF: Standard NRC Question1 A.3 b REF: Standard NRC Question1 A.4 a REF: Standard NRC Question1 A.5 b REF: Standard NRC Question1 A.6 a. 4; b. 2; c. 1; d. 3 REF: Standard NRC Question1 A.7 a REF: Standard NRC Question1 A.8 c REF: Standard NRC Question1 A.9 c REF: Standard NRC Question1.
Also: = (Keff - 1)/Keff (0.84 - 1)/0.84 = -0.16/0.84 = -0.19 K/K. 0.19/0.008 = $23.809 or $24 A.10 c REF: Standard NRC Question1.
Also: period = (doubling time) ÷ (ln(2)) = 42/0.693 = 60.6 . 61 A.11 a REF: NRC Exam administered 02/1991 Also: 9650gpm x 11EF x 142 watt/gpmEF = 15.6 x 106 watts; 15.6 x 106 ÷ 20.0 x 106 = 0.78 = 78%
A.12 b REF: Standard NRC Question1 A.13 d REF: Standard NRC Question1 A.14 a REF: Standard NRC Question1 A.15 c REF: Standard NRC Question1 A.16 a REF: Standard NRC Question1 A.17 c REF: Standard NRC Question1 A.18 c REF: Standard NRC Question1 A.19 c REF: Standard NRC Question1
Section A / Theory, Thermo & Fac. Operating Characteristics Page 32 1
NOTE: NIST does not supply a Text for Reactor Theory Training.
Section B Normal/Emergency Procedures & Radiological Controls Page 33 B.1 d REF: Annunciator Instruction 0.3.
B.2 b REF: NBSR Requalification Examination administered March 1996. Also T.S. § 2.2, p. 4.
B.3 d REF: T.S. 5.0 Time period definitions.
B.4 a, FP; b, Air; c, D2O; d, D2O REF: Standard NRC Question B.5 a, 4% ; b, 0.5% ; c, 15% ; d, 2.6%
REF: Technical Specifications § 4.0 (1) & (2), 3.3 (2)(b) and 3.4 Bases B.6 a, LSSS b, SL c, LCO; d, LCO REF: Technical Specifications, 2.1 2nd specification, 2.2 3rd specification 3.2 1st specification and 3.4 1st specification.
B.7 d REF: Administrative Rule 3.0, § III.A, also Administrative Rule 6.0 § I.B.
B.8 b REF: Rewrite of NBSR Requalification Examination question administered April 1998.
B.9 c REF: Emergency Instructions Manual, E.I. 1.5, "General Information", Page 5 of 5 B.10 a REF: Technical Specifications, § 4.0, Specifications (3) and (4).
B.11 a REF: Instrument reads only dose with window closed. Instrument reads both and dose with window open. Therefore, dose is window open dose less window closed dose.
B.12 a REF: Operation Instructions Manual, O.I. 5.7. "Operation of the Process Instrumentation Safety System", Page 2 of 3 B.13 a REF: Health Physics Procedures, H.P. 2.4, "Radiation Work Permit (RWP), Page 1 of 2 B.14 c
Section B Normal/Emergency Procedures & Radiological Controls Page 34 REF: Annunciator Procedures, A.P. 01 § III.A.
B.15 c or d Second choice added per facility comment.
REF: Emergency Instructions E.I. 4.4, § II.C.
B.16 a REF: TS, § 1.1.2 B.17 c REF Rewrite of NBSR Requalification Examination administered 1996, also OI 1.1 § II.I p. 4
Section C Facility and Radiation Monitoring Systems Page 35 C.1 A, Closed; B, Open; C, Open; D, Closed REF: NBSR Reactor Operations Training Guide, Figure 8.3 C.2 a REF: NBSR Reactor Operations Training Guide, §6.4.7, page 52.
C.3 a, 2; b, 1; c, 4; d, 3 REF: NBSR Reactor Operations Training Guide, C.4 b REF: Rewrite NBSR Requalification Examination question administered March, 1998.
C.5 a, B10 Counter; b, CIC; c, CIC; d, UIC REF: NBSR Reactor Operations Training Guide, C.6 d REF: Rewrite of NBSR Requalification Exam administered April 1998.
C.7 a REF: NBSR Requalification Exam administered April 1998.
C.8 d REF: NBSR Reactor Operations Training Guide, § 4.10.3 1st & 2nd ¶s.
C.9 b REF: NBSR Reactor Operations Training Guide, § 1.3.5 4th ¶.
C.10 c REF: NBSR Reactor Operations Training Guide, § 1.1.5 2nd ¶.
C.11 a, AC; b, AC/DC; c, AC/DC; d, DC REF: NBSR Training Guide, § 5.4, pp. 42-4328.
C.12 c REF: NIST Requalification Examination question administered January, 2000.
C.13 a REF: NBSR Training Guide, § 4.7.2, pp. 27-28.
C.14 b REF: NBSR Training Guide, § 4.1.2.2. 3rd ¶.
Section C Facility and Radiation Monitoring Systems Page 36 C.15 c REF: NBSR Training Guide, §§ 6.2.3 and 6.2.4, p. 46 C.16 a, 3; b, 1; c, 2; d, 4 REF: NBSR Training Guide, Figure I.2.
U. S. NUCLEAR REGULATORY COMMISSION NON-POWER INITIAL REACTOR LICENSE EXAMINATION FACILITY: National Institute of Standards and Technology REACTOR TYPE: NBSR DATE ADMINISTERED: 2002/03/01 REGION: I CANDIDATE:
INSTRUCTIONS TO CANDIDATE:
Write answers on the answer sheet provided. Attach answer sheets to the examination. Points for each question are indicated in brackets. A 70% overall is required to pass the examination. Examinations will be picked up three (3) hours after the examination starts.
%of Category % of Candidates Category Value Total Score Value Category A. Reactor Theory, Thermodynamics, and Facility 20 33.3 _____ _____ Operating Characteristics B. Normal and Emergency Operating Procedures and 20 33.3 _____ _____ Radiological Controls C. Plant and Radiation Monitoring Systems 20 33.3 _____ _____
60 _____ _____ TOTALS FINAL GRADE
All work done on this examination is my own. I have neither given nor received aid.
Candidates Signature
NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS During the administration of this examination the following rules apply:
- 1. Cheating on the examination means an automatic denial of your application and could result in more severe penalties.
- 2. After the examination has been completed, you must sign the statement on the cover sheet indicating that the work is your own and you have neither received nor given assistance in completing the examination. This must be done after you complete the examination.
- 3. Restroom trips are to be limited and only one candidate at a time may leave. You must avoid all contacts with anyone outside the examination room to avoid even the appearance or possibility of cheating.
- 4. Use black ink or dark pencil only to facilitate legible reproductions.
- 5. Print your name in the blank provided in the upper right-hand corner of the examination cover sheet and each answer sheet.
- 6. Mark your answers on the answer sheet provided. USE ONLY THE PAPER PROVIDED AND DO NOT WRITE ON THE BACK SIDE OF THE PAGE.
- 7. The point value for each question is indicated in [brackets] after the question.
- 8. If the intent of a question is unclear, ask questions of the examiner only.
- 9. When turning in your examination, assemble the completed examination with examination questions, examination aids and answer sheets. In addition turn in all scrap paper.
- 10. Ensure all information you wish to have evaluated as part of your answer is on your answer sheet. Scrap paper will be disposed of immediately following the examination.
- 11. To pass the examination you must achieve a grade of 70 percent or greater in each category.
- 12. There is a time limit of three (3) hours for completion of the examination.
- 13. When you have completed and turned in you examination, leave the examination area. If you are observed in this area while the examination is still in progress, your license may be denied or revoked.
REACTIVITY VALUES Total worth of 4 shim arms 25.6% $32 Worth of single shim arm 6.4% $8 Worth of regulating rod 0.64% $0.8 Maximum Reactivity Insertion Rate -0.04%/sec $0.05/sec Temp Coefficient (Operating temp. ~107EF) -0.016%/EF -$0.02/EF Void Coefficient (fuel region) -0.064%/liter -0.08/liter Upper Reflector Worth Rods In 4% $5 Rods Out 10% $12.5 Typical Beam Port Flooding D2O 0.2% $0.25 H2O -0.016% $0.02 Equilibrium Xenon ~3% $3.75 Equilibrium Samarium ~1% $1.25 Peak Xenon (above Samarium ~12% $15 CURRENT APPROXIMATE REACTIVITY BALANCE Temperature $5 Xenon - Samarium $5
Lifetime $4.5 Experiments Negligible Control at End-of-Life Negligible Total Excess Reactivity $10
Formulas K K&1 K &K Ct 1 1 C
' ' ' 2 1 M ' ' ' i ' 1&K K K K1 K2 Ci 1&K M Ct Ct 1 & K1 t
' R(
2 C t1 1 & K2 P ' P0 e ' $ $1 eff & eff & R(
' - ' < $1 ' (Instantaneous) > $1 R( % eff -
K ' üf p üth f ' N '
M Q0 ' m0 c P T P ' - th x N0 x f x3.2 x10&11 ' - th xV x f x 3.2x10&11 th
&X 2.3 0.693 2 2 TVL ' HVL ' I1D1 ' I2D2 I ' I0 e &µ x ' I010 TVL
µ µ X ' X0 e & t Where X can be A(activity), I(intensity), or N(number) T1/2 '
0.693 0.693 T1/2 R
6CE 0.5 C E P %
hr 2 2 ' eff eff (for large , i.e., rod drop) d (in feet) d (in meters) P0 %
eff C ' Curies and E ' energies
gal P (watts) ' Flow x t(EF) x C (constant) min 60 x 9.2 x 1 C (D2O) ' ' 162 3.413 60 x 8.34 x 1 C (H2O) ' ' 147 3.413
CONSTANTS WATER (@STP) 1 gal (H2O) 8.34 lb 1 gal (D2O) 9.2 lb 1 ft3 7.48 gal.
Density (H2O) 62.4 lb/ft3 or 1.0 g/cm3 Density (D2O) 68.95 lb/ft3 or 1.105 g/cm3 CP (H2O and D2O) 1.0 cal/g-EC POWER AND ENERGY 1 watt 1 Joule/sec or 3.413 BTU/hr 1 calorie 4.183 joules 1 BTU 1054 joules 1 Hp 2.54 x 103 BTU/hr Thermal Power (H2O) 147 watt/gpm-EF Thermal Power (D2O) 162 watt/gpm-EF REACTOR (NBSR)
R* 7 x 10-4 sec 0.0064 eff 0.008 bar 10 sec bar 0.1 sec-1 ACTIVITY 1 curie 3.7 x 1010 disintegrations per second or 2.22 x 1012 disintegrations per minute
a b
c d
Max Integral Rod Worth Curve C Critical Rod Height B
A 0
0 HC Rod fully out
D C B A Core Thermal Column Door Thermal Column Components
Rabbit Tip RABBIT SYSTEM Microswitch S
S A B S S C D Blower Process Room Receiver
A.8 A.7 A.6d A.6c A.6b A.6a A.5 A.4 A.3 A.2 A.1 Section a b c da ___
b c d 1___
2 3 41 ___
2 3 41 ___
2 3 14 2___
3 a4 b___
c da b___
c da b___
c da b___
c da b___
c d ___
ANSWER A.19 A.18 A.17 A.16 A.15 A.14 A.13 A.12 A.11 A.10 A.9 a b c da ___
b c d a ___
b c da b___c ad b___
c da b___
c ad b___
c da b___
c da b___
c ad b__c
B.6b B.6a B.5d B.5c B.5b B.5a B.4d B.4c B.4b B.4a B.3 B.2 B.1 Section SL LSSS SL LCO15 ___
15 1.015 4.0 0.54.0 2.6 ___
1.0150.54.0 2.6 ___
1.0 0.5 D Air 2.6 ___
1.0 2 0.5 OAir D2___
FP AirFPD2 O O___ ___
Air FPD2aO___
b FP c da___
b___
c da b___c d ___
ANSWER B.17 B.16 B.15 B.14 B.13 B.12 B.11 B.10 B.9 B.8B.7 B.6d a b c da b___ c d a___ b c da b___ c da b___c da ab___
bc cd da___
b___
c d a ___
b ca adb bc___
cd d ___
Section C.7 C.6 C.5d C.5c C.5b C.5a C.4 C.3d C.3c C.3b C.3a C.2 C.1d C.1c C.1b C.1a a b c da b___
c d B___
10 FC BUIC BUIC 10 FC___10 FC BUIC 10 FC___
a UIC b c d___
1 ___
2 3 41 2___ 3 41 2___ 3 41 2___
3 a4 b ___
c d Open
___ Open Closed Open
___ Open Closed Closed
___ Closed ANSWER C.16c C.16b C.16a C.16a C.15 C.14 C.13 C.12 C.11d C.11c C.11b C.11a C.10 C.
1 2 3 4 5 1___ 2 3 4 1 5 2 3___
41 52 3___
a4 ba5 cb ___
dc d___
a ___
b c da b___c d AC___DCACAC/DC DCACAC/DC
___ ___ AC___