ML20154D256

Exam Rept 50-297/OL-88-02 on 880426.Exam Results:Reactor Operator Passed

ML20154D256
Person / Time
Site:	North Carolina State University
Issue date:	05/05/1988
From:	Brockman K, Ernstes M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20154D225	List: ML20154D222 ML20154D256
References
50-297-OL-88-02, 50-297-OL-88-2, NUDOCS 8805190118
Download: ML20154D256 (26)

Text

_ .-_. . _ _ _ . .

i s l' s ENCLOSURE 1 EXAMINATION REPORT 297/0L-88-02 Facility Licensee: North Carolina State University Raleigh, NC 27695-7909 Facility Name: North Carolina State University Facility Docket No.: 50-297 A Written re-examination was administered at North Carolina State University near Raleigh, North Carolina.

Chief Examiner: h72ce N C. k b r/P/96 Michael Epnste m Date Signed Approved by: d #[f/ff' Dhter Signed Kenneth E. Brockm . Chief Opgfator Licensing Sec n2 Summary:

Examination on April 26, 1988. I One candidate was administered a written re-examination of categcry A; which he ,

passed.

I Based on the results described above, one of one R0 passed.

l l

, i 8805190118 880509 I PDR ADOCK 05000297  !

V DCD l l

. s 2

REPORT DETAILS

1. Facility Employees Contacted:

• G. D. Miller, Assiciate Director

• S. M. Grady, Chief Reactor Operator

• T. C. Bray, Reactor Operations Manager

• Attended Exit Meeting

2. Examiner:

• M. E. Ernstes

• Chief Examiner

3. Examination Review Meeting At the conclusion of the written examination, the . examiner provided t S. M. Grady, with a copy of the written examination and answer key for ,

review. There were no facility comments.

4. Exit Meeting  ;

~

At the conclusion of the site visit the examiner met with rep'esentatives-of the plant staff to discuss the results of the examination.

The cooperation given to the examiner was noted and appreciated.

The licensee did not identify as proprietary any of the material provided to or reviewed by the examiner.

d 6

t

, e' e' I l

l l i i

i I

l U. S. NUCLEAR REGULATORY COMMISSION REACTOR OPERATOR LICENSE EXAMINATION FACILITY: _NgRTH_gARgLINA_QTATE_ UNIV.

REACTOR TYPE: _TE@T____________________

DATE ADMINISTE9ED: _@@f@4f26________________

EXAMINER: _ERN@TEg_M_______________

CANDIDATE: _________________________

IN5IBUgIlgN@_IQ_g@Ng1981El Use separate paper for the answers. Write answers on one side only.

Staple question sheet on top of the answer sheets. Points for each question are indicated in parentheses after the questicn. The passing grade requires at least 70% in this category. Examination papers will be picked up one (1) hour after the examination starts.

% OF CATEGORY  % OF CANDIDATE'S CATEGORY

__y@6UE_ _IQI@L ___SCQ6E___ _Y@6UE__ ______________C@lEgg6Y_____________

_@@t@@__ 1@@t@@ ___________ ________ A. PRINCIPLES OF RCACTOR OPERATION

_2@t@@__ ___________ ________% Totals Final Grade All work done on thi s ex amination is my own. I have neither given nor received aid.

Candidate's Signature

(

t i NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS l

During the administration of this examination the following rules apply:

1. Cheating on the examination means an automatic denicl of your spplication and could result in more severe penalties.

2. Restroom trips are to be limited and only one candidate at a tima may leave. You must avoid all contacts with anyone outside the examination room to avoid even the appearance or riossibility of cheating.

3. Use black ink or dark pencil gnly to facilitate legible reproductions.

4 Print your name in the blank provided on the cover sheet of the examination.

5. Fill in the date on the cover sheet of the examination (if necescary).

6. Use only the paper provided for answers.

7. Print your name in the upper right-hand corner of the first pege of each section of the answer sheet.

8. Consecutively number each answer sheet, write "End of Category __" as appropriate, start each category on a ngw page, write gnly gn gne side of the paper, and write "Last Page" on the last answer sheet.

9. Number each answer as to category and number, for example, 1.4, 6.3.

10. Skip at least three lines between each answer.

11. Separate answer sheets from pad and place finished answer sheets face down on your desk or table.

12. Use abbreviations only if they are commonly used in facility literatute.

13. The point value for each question is indicated in parentheses after the question and can be used es a guide for the depth of answer required.

14. Show all calculations, methods, or assumptions used to obtain an answer to mathematical problems whether indicated in the question or not.

l 1

15. Partial credit may be given. Therefore, ANSWER ALL PARTS OF THE

)

DUESTION AND DO NOT LEAVE ANY ANSWER BLANK. '

16. If parts of the examination are not clear as to intent, ask questions of the enemi net onl y.

17. You must sign the statement on the cover sheet that indicates that the work is your own and you have not received or been given assistance in completing the examination. This must be done after the examination has been completed.

l l

l l

l l

j

4' . '.'.

s .

18. When you complete your examination, you shall:

a. Assemble your examination as f oll ows:

(1) Exam questions on top.

(2) 'Ex am aids - figures, tables, etc.

l (3) Answer pages including figures which are part of the answer.

l l b. Turn in your copy of the examination and all pages used to answer I the examination que s' '. ons .

c. Turn in all scrap paper and the balance of the paper that you did not use for answering the questions.

i

d. Leave the examination area. as defined by the examiner. If after leaving, you are found in this area while the examination is still in progress, your license may be denied or revoked.

4

. i A '. ' PRINCIPLES OF REACTOR OPERATION PAGE 2 j i ,

QUESTION A.01 (1.00)

Which one of the f ollowing statements concerning control rod worth in NOT TRUE?

a. Control rod worths chance during the lifetime of the rod.

b. Control rods are worth more at the center of the reactor because the neutron flux is relatively low at thu edges of a reactor,

c. A control rod's worth at any point is appr ox i ma tel y p ropor ti on al to the sauare of the therm &l neutron flux at that point.

d. A control rod's worth is lower at hioher moderator temperatures.

I i

I l

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

. i

, A. . PRINCIPLES OF REACTOR OPERATION PAGE 3 QUESTION A.02 (1.001 Which one of the following statements is NOT TRUE concerning an "apparent" startup rate observed while pulling rods during a reactor startup? I

a. It is caused by changing the effective multiplication factor from subcr1tical multiplication level to another,

b. K-eff = 1 l

c. It will eventually decrease to zero after rod pull is stopped.

d. The neutron population is actually increasing.

i I

l i

l

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

i <

f

. _ _ , _ . . . _ . ____ _ _ _ ,._ _ . ,_.... _ _.- _ ~. _ _ ,- _ _ .. _ _- . _

. i A. ' PRINCIPLES OF REACTOR OPERATION PAGE 4 t

QUESTION A.03 (1.00)

During a reactor startup you have just verified a constant positive startup rate on SR Nuclear Instruments after rod motion has stopped and no further reattivity is inserted. The actual condition of the core with this indication is:

a. Prompt Critical

b. Critical

c. Supercitical

d. Subc r i t i c al i

l

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

l i

I

. , . - _ ~-

o E81NcleLES,_QE_BE8CIQB_,gEEEGIlgN PAGE 5 QUESTION A.04 (1.00) fiovement of the rods has the greatest effect on which one of the following factors?

a. Reproduction Factor

b. Fast Fission Factor

c. Thermal Utilization Factor

d. Resonance Escape Factor 1

I i

l i

1 1

i i

i j

! 1

(*4*** CATEGDRY A CONTINUED ON NEXT PAGE *****)

o s A ". PRINCIPLES OF REACTOR OPERATION PAGE 6 3 s l

l l

OUESTION A.05 (1.00)

Which one of the following terms is defined as "the energy equivalent of the mass defect"?

a. Excitation energy

b. Binding energy

c. Fission energy

d. Critical energy (At*** CATEGORY A CONTINUED ON NEXT PAGE *****)

' PAGE 7 b._ EBINCIELES_OE_BE8CIO8_OEEB81IOtd

)

QUESTION A.06 (1.00)

Which one of the followina statements concerning radioactive decay is correct?

e. When an element decays by beta emission, the new element will have increased in atomic number by one and the mass number will remain the same as the orioimal element.

b. When an element decays by alpha emission, the new element will have decreased in atomic number and mass number by two, from the orlainal element.

c. When an element decays by neutron emission, the new element will have increased in atomic number by one and decreased in mass number by one, from the orioinal element.

d. When an element decays by camma emission. the new element will have increased in atomic number by one and the mass number will remain the same es the original.

l l

(***** CATEGORY A CONTINUED ON N E /.1 PAGE $44**) .

I 1

l l

l

~

'I ._ EBINCIEL59_OE,_BE@CT,OB,_OBEB@T ION PAGE 8 QUESTION A.07 (1.00)

Which one of the f al1owinc, is the CORRECT reason for operation with thermal instead of fast neutrons?

a. Increased neutron efficiency sinct thermal neutrons are less l i kel y to leak out of the core han fast neutrons.

b. Reactors coerating primarily on fast neutrons are inherently unstable and have a higher risk of going prompt critical,

c. The fission cross section of the fuel is much higher for thermal neutrons than tast neutrons.

o. Doppler and moderator temperature coefficients become positive as n et.t t r on energy increases.

.***** CATEGURY A CONTINUED ON NEXT f' AGE *****)

a

' PAGE 9 l j & _ EBINCIPLES_QE_BE6CIQB_QEE8811QN j

l QUESTION A.08 (1.00)

Figure 1.18 is a representation of how the resonance peaks of U-238 "flatten out" or Doppler broaden as fuel temperature increases. Which one of the following lists the correct labels for the X and Y axes?

a. X is neutron flux. Y is interaction rate

b. X is neutron energy. Y is microscopic capture cross section

c. X is interaction rate. Y is neutron density

d. X is atom density of U-238, Y is neutron flux 1

i t

j l

C***** CATEGORY 4 CONTINUED ON NEXT PAGE vi***>

l

]

4

,,---.----.mm,.-.m._..m.-__-, . . - _ _ - - - , - - . _ , . , ~ , . . ,-.,_...-,.-_y_.-,,.m, ,,,wm.-,. ---

. 'A . . PRINCIPLES OF REACTOR QPEBATigN PAGE 10 4 . , .

QUESTION A.09 (1.00)

During a reactor startup, equal increments of reactivity are added and the count rate is allowed to reach equilibrium each time. Choose the bracketed (E]) words that describe what is observed on the Source Range recorder and Startup Rate meter, a.The change in equilibrium count rate is Clarger] [the same]

r.smal l er ] each time.

b. The time required to reach equilibrium is Elonger] Ethe same]

[ shorter] each time.

P i

1

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

I g I

1 I,

b

\q 1

~

4 i

\x .:.

V .;. ,:.

i j

l l LQ, $s l$

o

, ,,.,_,-_----,,_,-,.,_,.__.,,7,--_---.wn-.,-,,_ ,.-

- - , , , ,--_n. .,- - _ . ,_ -., _ __-, ,__ ._,_ _ ,,

'A. . PRINCIPLES OF REACTOR OPERATION PAGE 11 l l

. I i  !

f A.10  ;

QUESTION (1.50)  ;

i t Indicate whether the following conditions will cause the Fuel Temperature 1 Coefficient (pcm/deg F) to become MORE negative, LESS negative or have i

NO EffECT. (Assume all other parameters are constant, consider each  :

i separately.)

a. The relative ratio of Pu-240 to U-238 increases tJ . MOderatOF temperature decreases (fuel temperature remainG Constant) i

c. Fuel temperature increases a

i 4

i i

f i

J G

.i I

N i )

i i

e i

I 1

i i i

} I J

a i

i i

} ( * * *. 4

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

a i

l i

i i

i

e.__EBINCIPLES_QE_SE8CIQB_QEEB8IlgN PAGE 12 OUESTION A.11 (2.00)

STATE how (INCREASE, DECREASE, or REMAIN THE SAME) an increase in moderator temoerature will affect EACH of the followino parameters. l l

a. Resonance Escape Probability

b. Thermal Utilization Factor

c. Fast Non-Leakage Probability

d. Fast Fission Factor 4

W l

(***** CATEGORY 4 CONTINUED ON NEXT PAGE *****)

8 __EBINg1ELES_QE_8E8gIQ8_QEE8@IlON PAGE 13 i

1 J

1 QUESTION A . 1 '2 (1.50) j .4nswer as 16UE or FALSE each of the followir.o concerning Xenon.

i

t. The half-1ife of Xenon-135 is about 40 hrs, i

2. Eauilibrium enen is dependent on power level, i I ,

3. Foal: xenon is independent of power level.  !

i i I i

i 1

l i

l 1

.I 4

l.

l d

e I

(

I l

?

a k

i l i

I l

i i

i t***** CATEGDF(Y A CONTIflUED OtJ NEXT PAGE *****>

f 4

e

• e i *

. A.. FRINCIPLES OF REACTOR OPERATION PAGE 14 I

t . .. .

! OUESTION A.13 (2.00) l For each of the following definitions. STATE the term that in defined.

l a. The effective fraction of all neutrons that cause fission that were i born delaved.

l b. The inverse of the time reauired to change power by a factor of 10.

l j c. A material that scatters neutrons back into the core reducing neutron 1eakage,

d. A plot showing the rolatianship of the change in react.ivity per unit lenoth for a control rod at any position in the reactor.

4, f

t t

l 1

1

i.

! t o

i i

l l

l i

i l

i i

l j

(***** CATEGORY f4 CONTINUED ON NEXT PAGE *****)

l

82. _ESINCIELES,,,gE_6E8CIQB_QEE69119N PAGE 15 l i

a .. .

i I

f,

. QUESTION A.14 (1.00) i I

If the reactor is operat'.no in the power range, CALCULATE how long it will l

I take to raise power from 20% to 40% full power with a +0.5 DPM startup rate. Show your work.

I i

I l

l  ;

i  :

i I I I a

i I i  !

e i

l

, i l  !

! I i .

?

+

i l

i l

I e

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

a re w ww w%m e.,-o. -ye np ,% ,

PAGE 16 A _EBING1ELES_QE_BE@ gig 8_QEES@IlgN QUESTION A.15 (3.00)

Using the information from the below figure. CALCULATE the value of each term of the six factor formula.

1000 C hermal 5eutrons 200 leon-Fission Capture By he fuel 600 if 2000 0 Thersel Fission fast Woutrons 30 m ,

1970 u Fast Fission -

, 75 2M5 Tast neutrons 200 1.sak Out gg$

Epitbernal Meutrons if 1245 W I***** C'P****

normal ,

3eutrons 200 I ***

• INS Detsal 3g Deutrons y Moderster and 800 Poison Absortti:n Thersal 3EGIN NIIT CTCU Neutrons u

) M n-Tissien 04;ture gg 3y Tual if Thersal Tission 1600 Fast Deutrons Y

(***** END OF CATEGORY () 8****)

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

- Bz _E81NCIELES_QE_8E8CIg8_gEEB811QN PAGE 17 t

ANSWERS'-- NORTH CAROLINA STATE UNIV.-89/04/26-ERNSTES M  ;

ANSWER A.01 (1.00)

(d)

REFERENCE DPC. Fundamental s of Nuclear Reactor Engineering, p. 135-140 ANSWER A.02 (1.00)

(b)

REFERENCE OPC. Fundamentals of Nuclear Reactor Engineering, p. 120 ANSWER A.03 (1.00)

I (c) l REFERENCE DPC. Fundamentals of Nuclear Reactor Engineering, p.120 l Nuclear Enerov Training. Reactor Operations, NUS Corp. ,

paragraph 12.4  !

a 2.8/3.1 001000K554 ...(KA*S) i AN5WER A.04 (1.00)

(c)  !

)

REFERENCE DPC. Fundamental s at Nuclear Reactor Engineering, p. 73 ANSWER A.05 (1.00)

(b)

REFERENCE DPC. Fundamentals of Nuclear Reactor Engineering, p. 17 I

.-m, . _ - . - - , _ . . . . _ . . _ . _ , . , - - - . _ _ . - _ _ . . , . _ _ _ , _ _ _

. . . - . . - _ ~ _ . - _ - ._ ~ ..- . - _ - - - .

A. PAGE 18

+

PRINC'PLES_QE_REACTQR_QPERATION ANSWERS'-- NORTH CAROLINA STATE UNIV.-88/04/26-ERNETES M l I

l  !

.i  !

5 l i

ANSWER A.06 (1.00) l 1

(a) i I

REFERENCE +

NETRO, S. 7.2, 7.3. 7.4.

DPC, Fundernental s of Nuclear Reactor Engineering, p.159 j ANSWER A 07 ti.00) l (c)

REFERENCE DPC. Fundamentals of Nuclear Reactor Engineering. p. 23 5

i f

i i J .

I ANSWER A.08 (1.00) +

}

(b) j i  !

' REFERENCE  ;

} CR. Doppler Coefficient, M.G. Weram, p 7. l j DPC. Fundamentals of Nuclear Deactor Engineering, p. 147 E 1

l <

! [

t ANSWER A.09 (1.00) ,

! I

a. larger [

l 4

b. lonaer ,

) i i

j REFERENCE ,

DPC. Fundament als of Nuclear Reactor Engineerino, p.117 j 3.9/4.0 192008K103 ...(KA'S) o

! l i l i

i

, ANSWER A.10 (1.50)  !

d l

a. more negative (0.5 EACH) l 4

b. less negative  !

c. loss neoative l i

I j REFERENCE i j NUS. Vol 3. unit 9.1 l DPC, Fundamentals of Nuclear Reactor Engineering, pp. 146-149  !

i i

i i

i  !

e '

e Osnfi31LIC.1[L $,QE_BE6CJOB_QEER911QN PAGE 19 AN5kDiS *- NORTH C AROLINA STALE UNIV.-80/04/26-EhN5TES M ANSUER 4.11 (2.00)

a. DECREASE (0.5 cach)

b. INCNEASE  !

c. DECREASE

d. INCREASE REFERENCE DPC, Fundamentain c4 Nuclear Reactor Enaineerino, pp. 61 - 7; Westinghouse Nuclear Trainina Operations, pp. I-2.31 - ,o A 12 '

ANSWER )

1. FnL5E

? fnUE

3. . rALsE REFEFENCE DPC, Fundamentalt o' to 1 clear hoactor Enoinr+rino, p0. 151 - 161 ANSWER s.Is 42.00) e D-ofd ( Es e t a oficctive)

D. htart un rate <

I

c. reflector

d. 01 t' f er en t i a l r o -a w a - t h c ur m REFENENCE DPC. Fundamer it e l n ci Nuclear hoactor Encinnerino, pp. 38.93.134,1?.?

l l

AN6WER (s . 14 (l.Cd) l l

Ju suc. t+/- 1sec)

RE F ER E M:E DPC. f'U n d einePn t til n et Nuc l ear h e it c t er Enoineering, p.94 2 . r.5 / 2 . 5 192CW/L101 . (F A' S)

)

e q b

'O s . . _[ B I N Q 1[L:EG gE_6EAGIOR_OFJBOII.ON PAGE 20 fiNSWE$kS' -- NORT H CAROLINA 9 FATE UNIV.-88/04/26-ERNSTES M AN5WER A.15 ('. 00) taut + 1 s n 2 at (e) : 204',/2000 e 1.0225 fast leakage (Li) : 1845/2045 m 0.902 renonance caoture (p) 1245/104b = 0.675 thermal 1eakago (Ltn) . 1045/1245 = 0. 839 t her mal abscrptton (f) : 800/104b = 0.766 reproduction (n) : 1600/600 = 2.000 hEFERENCE DF C , Fundamentals et Nuclear Reactor Enoineerino, p. G6

I .,

TEST CROSS REFERENCE PAGE 1 QUESTJ QN , VALUE REFERENCE A.01 1.00 MEE0001335 A.02 1.00 MEE0001338 4.03 1.00 t1EE0001330 4.04 1.00 MEE0001336 A.05 1.00 MEE0001337 A.06 1.00 (1EE0001339 A.07 1.00 MEE0001341 A.08 1.00 MEE0001343 A.09 1.00 MEE0001329 A.10 1.50 MEEOC01340 A.11 2.00 MEE0001342 A.12 1.50 MEE0001334 A.13 2.00 MEE0001333 A.14 1.00 MEE0001331 4.IS 3.00 MEF.0001332 20.00 20.00 LOCFET NO 297 i

l l

l l

l

,