Text

Initial Examination Report No. 50-073/OL-02-01
	ML020160504
Person / Time
Site:	Vallecitos Nuclear Center
Issue date:	01/25/2002
From:	Madden P; Operational Experience and Non-Power Reactors Branch
To:	Ehrlich E; General Electric Co
	Eresian W, NRC/NRR/DRIP/REXB, 415-1833
References
	50-073/OL-02-01 50-073/OL-02-01
	Download: ML020160504 (19)
	v • d • e

January 25, 2002 Mr. Edward Ehrlich Nuclear Test Reactor Manager General Electric Company Vallecitos Nuclear Center 6705 Vallecitos Road Sunol, CA 94586

SUBJECT:

INITIAL EXAMINATION REPORT NO. 50-073/OL-02-01

Dear Mr. Ehrlich:

During the week of November 12, 2001, the NRC administered a retake examination to an employee of your facility who had applied for a license to operate your General Electric Test reactor. The examination was conducted in accordance with NUREG-1478, "Non-Power Reactor Operator Licensing Examiner Standards," Revision 1. At the conclusion of the examination, the examination questions and preliminary findings were discussed with those members of your staff identified in the enclosed report.

In accordance with 10 CFR 2.790 of the Commission's regulations, a copy of this letter and the enclosures will 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/index.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 Mr. Warren Eresian at 301-415-1833 or internet e-mail wje@nrc.gov.

Sincerely,

/RA by Marvin Mendonca Acting for/

Patrick M. Madden, Section Chief Non-Power Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket No.50-073

Enclosures:

1. Initial Examination Report No. 50-073/OL-02-01

2. Examination and answer key cc w/encls:

Please see next page

General Electric Company (NTR)

Docket No. 50-73 cc:

Mr. Steve Hsu Radiologic Health Branch State Department of Health Service P.O. Box 942732 Sacramento, CA 94234-7320 California Department of Health ATTN: Chief, Environmental Radiation Control Unit Radiological Health Section 714 P Street, Room 498 Sacramento, CA 95814 Mr. Chuck Bassett, Manager Regulatory Compliance Vallecitos and Morris Operations Vallecitos Nuclear Center General Electric Company 6705 Vallecitos Road Sunol, CA 94586 Test, Research, and Training Reactor Newsletter University of Florida 202 Nuclear Sciences Center Gainesville, FL 32611 Mr. Chris Hamilton Senior Licensing Engineer Certified Six Sigma Green Belt Vallecitos Nuclear Center Sunol, CA 94586 Mr. Harold Neems General Electric Company Nuclear Energy Business Operations 175 Cutner Avenue Mail Code 123 San Jose, CA 95125

January 25, 2002 Mr. Edward Ehrlich Nuclear Test Reactor Manager General Electric Company Vallecitos Nuclear Center 6705 Vallecitos Road Sunol, CA 94586

SUBJECT:

INITIAL EXAMINATION REPORT NO. 50-073/OL-02-01

Dear Mr. Ehrlich:

During the week of November 12, 2001, the NRC administered a retake examination to an employee of your facility who had applied for a license to operate your General Electric Test reactor. The examination was conducted in accordance with NUREG-1478, "Non-Power Reactor Operator Licensing Examiner Standards," Revision 1. At the conclusion of the examination, the examination questions and preliminary findings were discussed with those members of your staff identified in the enclosed report.

In accordance with 10 CFR 2.790 of the Commission's regulations, a copy of this letter and the enclosures will 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/index.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 Mr. Warren Eresian at 301-415-1833 or internet e-mail wje@nrc.gov.

Sincerely,

/RA by Marvin Mendonca Acting for/

Patrick M. Madden, Section Chief Non-Power Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket No.50-073

Enclosures:

1. Initial Examination Report No. 50-073/OL-02-01

2. Examination and answer key cc w/encls:

Please see next page DISTRIBUTION w/encls.:

DISTRIBUTION w/o encls.:

PUBLIC RORP r/f MMendonca, PM WEresian Facility File (EBarnhill O6-D17)

PMadden WBeckner ADAMS ACCESSION #: ML020160504 TEMPLATE #: NRR-074

Please see previous concurrence OFFICE RORP:CE E

IEHB:LA E

RORP:SC NAME

WEresian:rdr

EBarnhill PMadden DATE 01/ 17 /2002 01/ 22 /2002 01/ 24 /2002 C = COVER E = COVER & ENCLOSURE N = NO COPY OFFICIAL RECORD COPY

U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.:

50-073/OL-02-01 FACILITY DOCKET NO.:

50-073 FACILITY LICENSE NO.:

R-33 FACILITY:

General Electric - Vallecitos Nuclear Center EXAMINATION DATES:

November 14, 2001 EXAMINER:

Warren Eresian, Chief Examiner SUBMITTED BY:

Paul V. Doyle, Acting for 12/21/2001 Warren Eresian, Chief Examiner Date

SUMMARY

During the week of November 12, 2001, the NRC administered an operator licensing retake examination to one Reactor Operator candidate. The examination, consisting of Category A, was administered by the facility. The candidate passed the examination.

REPORT DETAILS 1.

Examiner: Warren Eresian, Chief Examiner 2.

Results:

RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 1/0 N/A 1/0 Operating Tests N/A N/A N/A Overall 1/0 N/A 1/0 3.

Exit Meeting: None ENCLOSURE 1

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

General Electric REACTOR TYPE:

Test Reactor DATE ADMINISTERED:

11/14/01 REGION:

4 CANDIDATE:___________________________

INSTRUCTIONS TO CANDIDATE:

Answers are to be written on the exam page itself, or the answer sheet provided. Write answers one side ONLY. Attach any answer sheets to the examination. Points for each question are indicated in parentheses for each question. A 70% is required to pass the examination.

Examination will be picked up one (1) hour after the examination starts.

% OF CATEGORY

% OF CANDIDATE'S CATEGORY VALUE TOTAL SCORE VALUE CATEGORY 20 100 A. REACTOR THEORY, THERMODYNAMICS, AND FACILITY OPERATING CHARACTERISTICS FINAL GRADE All work done on this examination is my own. I have neither given nor received aid.

Candidate's Signature ENCLOSURE 2

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 not received or 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.

6.

Print your name in the upper right-hand corner of the answer sheets.

7.

The point value for each question is indicated in parentheses after the question.

8.

Partial credit may be given. Therefore, ANSWER ALL PARTS OF THE QUESTION AND DO NOT LEAVE ANY ANSWER BLANK. NOTE: partial credit will NOT be given on multiple choice questions.

9.

If the intent of a question is unclear, ask questions of the examiner only.

10.

When turning in your examination, assemble the completed examination with examination questions, examination aids and answer sheets. In addition, turn in all scrap paper.

11.

When you are done and have turned in your examination, leave the examination area as defined by the examiner. If you are found in this area while the examination is still in progress, your license may be denied or revoked.

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 3 QUESTION: 001 (1.00)

A reactor is subcritical with a Keff of 0.955. Seven dollars ($7.00) of positive reactivity is inserted into the core

( = 0.007). At this point, the reactor is:

a.

subcritical.

b.

exactly critical.

c.

supercritical.

d.

prompt critical.

QUESTION: 002 (1.00)

Which ONE of the following is true concerning the differences between prompt and delayed neutrons?

a.

Prompt neutrons account for less than one percent of the neutron population while delayed neutrons account for approximately ninety-nine percent of the neutron population.

b.

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

c.

Prompt neutrons are released during the fission process while delayed neutrons are released during the decay of fission products.

d.

For small reactivity insertions, prompt neutrons are the dominating factor in determining the reactor period while delayed neutrons have little effect on the reactor period.

QUESTION: 003 (1.00)

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.

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 4 QUESTION: 004 (1.00)

Which ONE of the following is the approximate time period during which the MAXIMUM amount of Xenon-135 will be present in the core?

a.

15 to 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months after a startup to 100% power.

b.

10 to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after a shutdown from 100% power.

c.

10 to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after a power decrease from 100% to 50% power.

d.

15 to 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months after a power increase from 50% to 100% power.

QUESTION: 005 (1.00)

During a reactor startup, the count rate is increasing linearly with time, with no rod motion. This means that:

a.

the reactor is subcritical and the count rate increase is due to the buildup of delayed neutron precursors.

b.

the reactor is critical and the count rate increase is due to source neutrons.

c.

the reactor is subcritical and the count rate increase is due to source neutrons.

d.

the reactor is critical and the count rate increase is due to the buildup of delayed neutron precursors.

QUESTION: 006 (1.00)

Which ONE of the reactions below is an example of a photoneutron source?

a.

51Sb123 + n -> 51Sb124 +

b.

92U238 -> 35Br87 +57La148 + 3n +

c.

4Be9 + -> 4B8 + n d.

4Be9 + -> 6C12 + n

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 5 QUESTION: 007 (1.00)

Which ONE of the following is the reason for operating with thermal neutrons rather than fast neutrons?

a.

Probability of fission is increased since thermal neutrons are less likely to leak out of the core.

b.

The absorption cross-section of U-235 is much higher for thermal neutrons.

c.

The fuel temperature coefficient for fast neutrons is positive, whereas for thermal neutrons it is negative.

d.

The beta fraction for thermal neutrons is lower, so that prompt criticality is not as likely.

QUESTION: 008 (1.00)

For a beta effective = 0.0074, a reactivity insertion of 20 cents corresponds approximately to:

a.

0.0010 delta k/k.

b.

0.0015 delta k/k.

c.

0.0020 delta k/k.

d.

0.0074 delta k/k.

QUESTION: 009 (1.00)

During the minutes following a reactor scram, reactor power decreases on a negative 80 second period, corresponding to the half-life of the longest lived delayed neutron precursor, which is approximately:

a.

20 seconds.

b.

40 seconds.

c.

55 seconds.

d.

80 seconds.

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 6 QUESTION: 010 (1.00)

The fuel-to-moderator ratio describes the relationship between the number of fuel atoms in a volume of core to the number of moderator atoms. A reactor which is:

a.

undermoderated will have a positive moderator temperature coefficient.

b.

undermoderated will have a negative moderator temperature coefficient.

c.

overmoderated will have a constant moderator temperature coefficient.

d.

overmoderated will have a negative moderator temperature coefficient.

QUESTION: 011 (1.00)

You enter the control room and observe that the neutron instrumentation indicates a steady neutron level with no rods in motion. Which ONE condition below CANNOT be true?

a.

The reactor is critical.

b.

The reactor is subcritical.

c.

The reactor is supercritical.

d.

The neutron source is out of the core.

QUESTION: 012 (1.00)

Which factor in the six-factor formula is represented by the ratio:

number of neutrons that reach thermal energy number of neutrons after fast leakage a.

Fast non-leakage probability.

b.

Resonance escape probability.

c.

Reproduction factor.

d.

Thermal utilization factor.

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 7 QUESTION: 013 (1.00)

Inelastic scattering can be described as a process whereby a neutron collides with a nucleus and:

a.

reappears with a lower kinetic energy, with the nucleus emitting a gamma ray.

b.

reappears with the same kinetic energy it had prior to the collision.

c.

is absorbed by the nucleus, with the nucleus emitting a gamma ray.

d.

reappears with a higher kinetic energy, with the nucleus absorbing a gamma ray.

QUESTION: 014 (1.00)

Two different neutron sources are used during two reactor startups. The source used in the first startup emits ten times as many neutrons as the source used in the second startup. Assume all other factors are the same for the two startups. Which ONE of the following describes the expected result at criticality.?

a.

Neutron flux will be higher for the first startup.

b.

Neutron flux will be higher for the second startup.

c.

The first startup will result in the rods being further out of the core.

d.

The second startup will result in the rods being further out of the core.

QUESTION: 015 (1.00)

Which ONE of the following is the major source of energy released due to thermal fission of a U-235 atom?

a.

Gammas from fission product decay.

b.

Kinetic energy of the fission neutrons.

c.

Prompt gammas.

d.

Kinetic energy of the fission fragments.

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 8 QUESTION: 016 (1.00)

Which ONE of the following describes the term prompt critical?

a.

The instantaneous change in power level due to withdrawing a control rod.

b.

A negative reactivity insertion which is greater than beta-effective.

c.

A reactor which is critical on prompt neutrons only.

d.

A positive reactivity insertion which is less than beta-effective.

QUESTION: 017 (1.00)

A thermal neutron is a neutron which:

a.

experiences no net change in its energy after several collisions with atoms of the moderating medium.

b.

has been produced several seconds after its initiating fission occurred.

c.

is produced as a result of thermal fission.

d.

possesses thermal energy rather than kinetic energy.

QUESTION: 018 (1.00)

During the neutron cycle from one generation to the next, several processes occur that may increase or decrease the available number of neutrons. Which ONE of the following factors describes an INCREASE in the number of neutrons during the cycle?

a.

Thermal utilization factor.

b.

Resonance escape probability.

c.

Thermal non-leakage probability.

d.

Fast fission factor.

(***** CATEGORY A CONTINUED ON NEXT PAGE *****)

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS Page 9 QUESTION: 019 (1.00)

The moderator temperature coefficient of reactivity is -1.25x10-3 delta K/K/deg.C. When a control rod with an average rod worth of 0.1% delta K/K/inch is withdrawn 10 inches, reactor power increases and becomes stable at a higher level. At this point, the moderator temperature has:

a.

increased by 8 deg C.

b.

decreased by 8 deg C.

c.

increased by 0.8 deg C.

d.

decreased by 0.8 deg C.

QUESTION: 020 (1.00)

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.

increasing, then decreasing.

c.

continually decreasing.

d.

constant.

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

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

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS ANSWER: 001 (1.00)

C.

REFERENCE:

A.

REFERENCE:

Reactor Physics Training Manual, Section A, Basic Reactor Physics Definitions.

ANSWER: 020 (1.00)

A.

REFERENCE:

Reactor Physics Training Manual,Section I, Reactor Kinetics.

A. REACTOR THEORY, THERMODYNAMICS AND FACILITY OPERATING CHARACTERISTICS ANSWER SHEET MULTIPLE CHOICE (Circle or X your choice)

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

001 a

b c

d _____

002 a

b c

d _____

003 a

b c

d _____

004 a

b c

d _____

005 a

b c

d _____

006 a

b c

d _____

007 a

b c

d _____

008 a

b c

d _____

009 a

b c

d _____

010 a

b c

d _____

011 a

b c

d _____

012 a

b c

d _____

013 a

b c

d _____

014 a

b c

d _____

015 a

b c

d _____

016 a

b c

d _____

017 a

b c

d _____

018 a

b c

d _____

019 a

b c

d _____

020 a

b c

d _____

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

EQUATION SHEET Q = m cp T CR1 (1-Keff)1 = CR2 (1-Keff)2 SUR = 26.06/

P = P0 10SUR(t)

P = P0 e(t/)

= (*/) + [(-)/eff]

eff = 0.1 seconds-1 DR1D1 2 = DR2D2 2

DR = DRoe-t DR = 6CiE/D2

= (Keff-1)/Keff 1 eV = 1.6x10-19 watt-sec.

1 Curie = 3.7x1010 dps 1 gallon water = 8.34 pounds 1 Btu = 778 ft-lbf

F = 9/5C + 32 1 Mw = 3.41x106 BTU/hr

C = 5/9 (F - 32)

ML020160504

Contents

Text

SUBJECT:

Dear Mr. Ehrlich:

Enclosures:

SUBJECT:

Dear Mr. Ehrlich:

Enclosures:

SUMMARY

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

Navigation menu

ML020160504

Text

SUBJECT:

Dear Mr. Ehrlich:

Enclosures:

SUBJECT:

Dear Mr. Ehrlich:

Enclosures:

SUMMARY

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

REFERENCE:

Navigation menu

Search