ML20136D566

Exam Rept 50-073/OL-85-01 on 851112-13.Exam Results:Senior Reactor Operator Candidate Passed Exams

ML20136D566
Person / Time
Site:	Vallecitos Nuclear Center
Issue date:	12/06/1985
From:	Pate R, James Smith NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML20136D541	List: ML20136D536 ML20136D566
References
50-073-OL-85-01, 50-73-OL-85-1, NUDOCS 8601060209
Download: ML20136D566 (40)

Text

.

EXAMINATION REPORT FACILITY LICENSEE:

General Electric Co.

Vallecitos Nuclear Center Pleasanton, California 94566 FACILITY DOCKET NO.:

50-73 Exam Report No. 50-73/0L-85-01 FACILITY LICENSE NO.:

R-33 Examinations adn.inistered at the General Electric Company Nuclear Test Reactor near Pleasonton, California Chief Examiner:

/ / ~ 2 /~8I JohirD. Smith Date Signed Approved By:

dp

/

/ 2-

[f 1

Robert Pate, Branch Chief Date Signed

~

SUMMARY

Examinations on November 12-13, 1985 Written and oral examinations were administered to one SR0 candidate. The candidate passeo these examinations.

W n"a PA"63 a

l

2 REPORT DETAIIE 1.

. EXAMINER (S)

• J. D. Smith, PNL 2.

EXAMINATION REVIDi MEETING At the conclusion of the written examination, the Exauniner tret with William Johnson and Earl Strain of the facility staff to review the written examination and answer key.

The facility conments on the exantination and answer key and the resolution of the comments are appended to this report.

3.

EXIT MEETING At the conclusion of the site visit, the examiner met with a member of the facility staff to discuss the results of the examination. He was informed at this meeting that the candidate had clearly passed the oral and operating examination.

• Chief Examiner

3 FACILITY COMMENTS AND RESOLUTION Comment Resolution Q J.4 Q J.4 Include reflector movement Reflector movement added to ir. Answer Key Answer Key Q J.8 Q J.8 Substitute the word control The word regulating changed for regulating in Answer Key to control in Answer Key Q J.9 Q J.9 Table 8-1 in the G.E. NTR SAR Answer Key changed to:

inaccurate. Current scram setpoints are:

Linear Hi Power 120 KW Linear Hi Power 120 KW Linear lo Voltage 650 V Linear lo Voltage 650 V Log N Hi Power 150 KW Log N Hi Power 150 KW Log N Period 6 sec Log N Period 6 sec Log N Lo Voltage 570 V Log N Lo Voltage 570 Y PRI Coolant Hi Temp 140 F Pri Coolant Hi Temp 140 F Pri Coolant Lo Flow 17.3 gpm Pri Coolant-Lo Flow 17.3 gpm Add seismic trip at 0.71 mm Added seismic trip at 0.71 mm movement.

movement to Answer Key 4 K.2 Q K.2 NTR no longer has a fuel Removed the words "with fuel storage reel storage reel empty" from Part 4 of Answer Key m

U. S. NUCLEAR REGULATORY COINISSION SENIOR REisCTOR OPERATOR LICENSE EXAMINA110N

=

^

Facility: General Electric NTR

(;nArveis Aao r

Reactor Type: Light Water Moderated Oate Administered: November 12, 1985 as Examiner:

J. D. Smith Candidate: Answer Key MASTF4 m

INS 1RUC110NS 10 CANDIDATE:

I Write on one side only. Staple cuestion Use separate paper for the answers. Points for each question are indicated in sheet on top of the answer sheets.

parentheses after the question. The passing grade requires at least 70% in each Examination papers will be picked up six (6) hours af ter the category.

examination starts.

Category

% of Candidate's

% of Value Total Score Cat. Value Category H. Reactor Theory 20 19.4

1. Radioactive Materials 20 19.4 Handling, Disposal, and Hazards J. Specific Operating

___20 19.4 Characteristics K. Fuel Handling and 22 21.4 Core Parameters L. Administrative Procedures, 21 20.4

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Conditions, and Limitations TOTALS 103 Final Grade All work done on this examination is my own; I have neither given nor received aid.

Candidate's Signature

1 General Electric Co. NTR November 12, 1985 H.

REACTOR THEORY (20.0)

~

edints Available 00ESTION H.1 The General Electric Co. NTR is increasing power with a period of 25 seconds, a.

How much time is required for the power level to increase by two (2) decades? Show your calculations.

(2.0) 7 b.

What is the reactivity ~of the core?

(1.0)

ANSWER H.1 a.

T = 25 sec P/Po = 100 = e /25

(+1.0) t Ln 100 = t/25 t = 25 Ln 100

= 115 sec

(+1.0)

I

= 1.92 min i*#

p=3+fT

(+0.5) b.

• 1 + 0 b8 25 p = 0.24% delta k/k

(+0.5)

REFERENCE H.1 1.

Technical Education Research Center-Southwest, " Nuclear Technology",

p. 12-1-13 to 12-1-18.

l l

-Section H Continued on Next Page-I t

2 General Electric Co. NTR November 12, 1985 Points Available

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OUESTION H.2 Consider the " doppler broadening" effect that takes place in the fuel of the reactor, a.

Exclain what causes the phenomena of doppler broadening.

Include which isotopes are the main contributors.

(1.5) b.

As the temperature of the fuel increases, what parameter of the six-factor formula predominantly is affected and what impact does this have on k,ff?

(1.5)

ANSWER H.2 a.

An increase in the fuel temperature causes a broadening of the neutron absorption peaks (the resonance peaks); on a graph of neutron absorption cross-section as a function of energy the cross-section peaks widen and the peak value becomes smaller

(+0.5).

The broadening is due to the increased vibrational energy as the temperature increases (+0.5).

The peaks in the absorption cross-sections of U-235 and U-238 are the primary contributors to the effect in the reactor (+0.5).

b.

As the fuel temperature increases, the widening of the resonance peaks causes the resonance escape probability (+0.75) to decrease and hence, for k,ff to decrease (+0.75).

REFERENCE H.2 1.

Technical Education Research Center-Southwest, " Nuclear Technology,"

p. 12-7-8 to 12-1-9.

-Section H Continued on Next Page-

3 General Electric Co. NTR November 12, 1985 Points Available 00ESTION H.3 Gire two (2) reasons why Xe-135 has such a significant effect on reactor operation.

(2.0)

ANSWER H.3 Because of its high fission product yield.

Because of its very large thermal cross-section.

135 The critical half-life of Xe 1

[Any two (2), +1.0'each]

REFERENCE H.3 1.

NUS, Vol.'3, p. 10, 2-1.

1 i

[

-Section H Continued on :Jext Page-t

4 General Electric Co. NTR November 12, 1985 Points Available 00ESTION H.4 A nuclear reactor is shutdown by 7% delta k/k when the neutron detector is recording 20 cpm. What would this detector read (1.5) when k,ff = 0.987 ANSWER H.4 delta k 1 = 0.0 k i 1-k 1 = 0.07 k i 1=ki + 0.07 k1 1 = 1.07 kl kg = 1/1.07 = 0.93

(+0.5)

(+0.5)

=

1-k2 CRi uz. CRg 0.02 CRi CR2 = (20)(3.50)

= 70 cpm

(+0.5)

~

REFERENCE H.4 1.

Generic: " Academic Program for Nuclear Power Plant Personnel,"

Volume II, p. 5-6 through 5-13, General Physics Corporation.

T

-Section H Continued oa Next Page-

5 General Electric Co. NTR November 12, 1985 Points Available OUESTION H.S Why is the worth of a control rod dependent on the position of that control rod?

(1.0)

ANSWER H.S The reactivity effect, i.e., worth, of a control rod depends on the impact that the material of the control rod has on the absorption rate of neutrons'(assuming a poison-type of control rod). The reactivity worth of a small-sized absorber can be expressed as deoendent on the (relativel neutron flux in the vicinity of the absorber and the impact that a change in that location will have on the total neutron population. Mathematically, the result is that the effect is proportional to the square of the neutron flux at the location where the change is made in absorber concentration. Hence, changing the amount of absorber material near the center of.the reactor core will have the largest effect on reactivity.

The essence of the above. (+1.0)

REFERENCE H.S 1.

Stephenson, R., McGraw-Hill.

.I l

[

-Section H Continued on Next Page-l 1

6 General Electric Co. NTR November 12, 1985 Points Available OUESTION H.6 Indicate whether each of the following statements are TRUE or FALSE.

(2.5) a.

An increasing concentration in the reactor core of Xe-135 reduces the thermal utilization factor, f, and hence, the multiplication factor, k,ff, of the reactor core.

b.

The thermal-neutron microscopic absorption cross section of Xe-135 is greater than that of uranium, c.

Xe-135 is produced both directly as a fission product and as the result of a decay chain from other fission products.

d.

A good approximation for determining the production in a reactor core of Xe-135 is to assume that the Xe-135 is produced from the decay of Cs-135.

e.

The removal rate of Xe-135 is due to the neutron absorp-tion rate in Xe-135 atoms and due to the radioactive decay of Xe-135 atoms.

i ANSWER H.6 a.

TRUE b.

TRUE c.

TRUE d.

FALSE e.

TRUE

(+0.5each) l REFERENCES H.6 1.

Generic:. Academic Program for Nuclear Power Plant Personnel, Volume II, General Physics Operation, p. 4-144f.

2.

Technical Education Research Center-Southwest, " Nuclear Technology," p. 12-7-12f.

l

-Section H Continued on Next Page-l

7 General Electric Co. NTR November 12, 1985 Points Available OUESTION H.7 tion does p differ from geff (hy? larger / smaller) in the NTR Reactor and briefly explain w (2.0)

ANSWER H.7 is larger (+0.5).

Delayed neutrons are born with lower p kies (hence, fewer fast fissions), greater thermalization, e8 less fast neutron escape. Resulting in more thermal neutrons present (+1.5).

Hence,p,ff is la ger.

REFERENCE H.7 1.

NUS, Vol. 3, p. 5.3-3.

QUESTION H.8 Choose, by specifying a letter designation, the cost correct statement from those given below.

(1.0) a.

The unit (of measure) of the " barn" is a measure for the macroscopic neutron cross section.

b.

Delayed neutrons have at birth a harder energy spectrum than neutrons produced from the fissioning of U-235 by thermal neutrons.

c.

The microscopic cross section for neutron interaction depends upon the isotopic composition of the material and of the energy of the neutron.

d.

The reactor rate for neutron absorption in a given material is inversely proportional to neutron flux.

ANSWER H.8 c.

(+1.0)

REFERENCE H.8 l

1.

Generic:

" Academic Program for Nuclear Power Plant Personnel,"

l

' Volume I, General Physics Corporation, p. 4-25f.

-Section H Continued on Next Page-l

8 General Electric Co. NTR November 12, 1985 Points Available 00ESTION H.9 Answer TRUE or FALSE and briefly _fustify your answer.

a.

The time it takes to achieve peak Xe conditions following a shutdown is independent of the equilibrium power level prior to shutdown.

(1.0) b.

At equilibrium conditions of 80 kW at NTR Reactor, Xe-135 is removed mostly by decay to Cs-135.

(1.0) c.

The equilibrium Xe-135 concentration at 40 kW power is less than half to Xe-135 concentration at 80 kW.

(1.0)

ANSWER H.9 a.

FALSE - The lower the equilibrium power, the earlier the Xenon peaks. (+1.0) b.

FALSE - The absorption of neutrons for Xenon (burnout) is

~

larger than the effects of Xe decay.

(+1.0) c.

FALSE - It is about 70% high, due to higher burnout factor of Xe-135 at4bEBE power.

(+1.0)

Bonw REFERENCE H.9 1.

NUS, Vol. 3, pp. 10.2-2, 10.2-3 and 10.2-4.

QUESTIO!'_H la If reactor power steadily increases from 10 kW to about 27.2 kW in 100 seconds, what is the approximate period?

(1.0)

ANSWER H.10 100 sec (+1.0) i REFERENCE H.10 1.

NUS, Vol. 3, p. 6.3-3.

-End of Section H-

/

e 9

General Electric Co. NTR November 12, 1985 I.

RADIOACTIVE MATERIAL HANDLING. DISPOSAL AND HAZARDS (20.0)

'. Points Available OUESTION I.1 List six (6) of the eight (8) materials that shall not be handled as low level radwaste.

(3.0)

ANSWER I.1 None of the following shall be handled as low level radwaste:

• 1.

Liquids

• 2.

Transuranic waste greater than 10 nci/gm

• 3.

Absorbed liquids 4.

Pyrophoric material 5.

Explosives 6.

Material whose chemical hazard is greater than its radiological hazard 7.

Radwaste materials that are not chemically compatible (non-reactive) with any of the packaging materials with which it may come into contact

• 8.

Any radioactive waste material with radioactivity levels greater than 200 ar/hr maximum at contact "Unless special permission and approval are received from the Manager, RHO.

(+0.5 each, +3.0 maximum)

REFERENCE I.1 1.

3.2, 50P 9.7, p. 2.

-Section I Continued on Next Page-

10 General Electric Co. NTR November 12, 1985 Points Available OUESTION I.2 A target has been irradiated in the G.E. Co. NTR Reactor, a.

You anticpate that the target contains only one stable isotope of one low-Z element that has undergone a neutron absorption [(n,7) reaction]; you anticipate that the radioactive decay of the resulting radioactive isotope is a one-step decay to a new stable isotope. What type (s) of emissions would you anticipate would come from the radioactive target after it is removed from the reactor?

t Justify your answer.

(1.5) b.

After you have removed the target from the reactor, and over a period of time record the count rate from a detector placed next to this target, hnw would you determine the half-life of the radioactivity?

(1.5)

ANSWER I.2 i

a.

If a stable isotope of an element absorbs a neutron, it will form a new isotope that is above the line of stability (+0.75).

Isotopes of low-Z materials that are above this "line" usually decay toward the "line" by p-emission. Such p-emissions may be preceded by or may include the emission of one or several ys (+0.75).

j I

I

-Section I Continued on Next Page-

11 General Electric Co. NTR November 12, 1985

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Points Available ANSWER I.2 (contdl b.

The radioactive decay of a single radioactive isotope will follow the exponential decay law.

-At Ag=Ae 1

(+0.5) g

-At A2=Ae 2

n A.1,,-1(t -t )

i 2 A2 in A1 - In A2 = -A(t -t )

i 2 In A1 - in Ap A"

(+1.5) t -t2 l

then, 0.693 1/2

• A Graphically, you can plot in A(t) versus t and the slope of the graph is -1.

(+1.5)

(+1.5 max.)

REFERENCE I.2 1.

Technical Education Research Center-Southwest, p. 1-7 to 1-12.

i d

1

-Section I Continued on Next Page-

~-

12 General Electric Co. NTR November 12, 1985 Points Available

~ '

00ESTION I.3 N TR If the target of Question I.2 had been placed in the 555B Reactor and the reactor brought to 100% of full power, sketch the activity of the target as a function of time.

(2.0)

ANSWER I.3 a

Act.

A=Et(1-e-At) t

(+2.0 for shape or equation)

REFERENCE I.3 1.

Technical Education 'esearch Center-Southwest, p.1-15.

i l

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-Section 1 Continued on Next.Page-

13 General Electric Co. NTR November 12, 1985 Points Available 00ESTION I.4 If two centimeters of lead placed at a certain location in a beam of gamma rays would reduce the gamma ' radiation level from 100 mr/hr to 50 mr/hr, what thickness of lead placed in this beam would reduce the gamma radiation level from a.

400 mr/hr to 50 mr/hr?

(0.5) b.

50 mr/hr to 25 mr/hr?

(0,5)

ANSWER I.4 I

i a.

6 cm

(+0.5) i b.

2 cm

(+0.5)

REFERENCE I.4 1

Technical Education Research Center-Southwest, pp. 1-24, 1-25, 2-1, 2-2.

h OUESTION I.5 t

r If the gamma-ray radiation level from a pump (point source) had been 30 ar/hr.1 foot from the pump, what would be the radiation level 10 feet from the pump?

(1.0) l

+

f ANSWER I.5 Neglecting gamma-ray absorption by the air, distance factor = (fE)2 =Jhg

(+0.5) i rad level (10) = rad level (1)/100

= 0.30 mr/hr.

(+0,5) f REFERENCE I.5 i

1.

Generic: Nuclear Energy Training, Module 5, " Radiation Protection,"

p. 3.3-1 to 3.3-4.

-Section I Continued on Next Page-i I

-,~

.-.,._..,_.,n.-

,,.,_n,,,.,

14 General Electric Co. NTR November 12, 1985 Points Available

~

OUESTION I.6 If a man had been exposed to 0.01 R ganna radiation, 0.04 rad of beta radiation and 0.02 rad of fast neutrons, what is his total biological dose in rems? Shan your work.

(2.0)

ANSWER I.6 0.01 R of gamma x 1 QF = 0.01 rem 0.04 rad of beta x 1 QF = 0.04_ rem 0.02 rad of fast react x 10 QF = Q ZQ rem Total dose

= 0.25 rem

(+0.25 for dose equation, +2.0 for answer, +2.0 max.)

REFERENCES I.6 1.

Generic: Nuclear Energy Training, Module 5, " Radiation Protection," pp. 2.1-1 to 2.1-3.

2.

Technical Education Researc : Center-Southwest, p. 2-3.

3.

Code of Federal Regulations 10 CFR 20.4, p. 234.

i i

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l

-Section I Continued on Next Page-I

15 i

General Electric Co. NTR November 12, 1985 Points Available 00ESTION I.7 During i days work you worked in the following radiation areas:

a.

50 mr/hr for 6 min.

b.

10 mr/hr for 1.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />.

c.

80 mr/hr for 4 min.

d.

140 mr/hr for 4 min.

1.

Eng much exposure have you taken?

(1.0) 2.

How much longer could you work in a 100 mr/hr area if you are limited to a total of 40 mr/ day?

(1.0)

ANSWER I.7 a.

50 x 6 = 300 + 60 =

5 b.

10 x 90 = 900 + 60 = 15 c.

80 x 4 = 320 + 60 =

5.33 d.

140 x 4 = 560 + 60 = 2.11 1.

Total 34.6 or 35 M/ rem'

(+1.0)

'oo;r;;;=1.6mr/ min.

2.

'({^II = 3 min.

(+1.0)

REFERENCE I.7

~

1.

General Electric Co. NTR Requalification Exam I.4, p. 9 l

I

-Section I Continued on Next Page-

16 General Electric Co. NTR November 12, 1985 Points Available QUESTION I.8 What special survey precautions should be taken and why when using a portable Alpha survey meter?

(2.0)

ANSWER I.8 Precautions for use of Alpha meter are -

a.

Survey slowly (+0.5) - (Alpha meters have a slow time response).(+0.5) b.

Keep close to material being surveyed (+0.5).

(Alphaparticleshave limited travel in air.) (+0.5)

REFERENCE I.8 1.

General Electric Co. NTR Requalification Examination I.2, p. 9.

QUESTION I.9 Identifv the four (4) designated radwaste collection points and the.tyng of collector located at each collection point.

(4.0)

ANSWER I.9 Reactor cell (+0.5) one waste drum (+0.5) i Reactor cell door (+0.5) one waste bag (+0.5)

South cell (+0.5) one waste bag (+0.5)

SNM cage (+0.5) one wacte bag (+0.5) r REFERENCE I.9 1.

5.3, S0P 9.7, p. 6.

f

-End of Section I-t

)

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17 General Electric Co. NTR November 12, 1985 J.

SPECIFIC OPERATING CHARACTERISTICS (20.0)

Points

Avillable OUESTION J.1 Exclain what is meant by the term " turnover point",

include value.

(2.5)

ANSWER J.1 The overall temoerature coefficient (+0.5) of the fuel annulus

(+0.5) was measured and found to be oositive un to 124"F (+0.5).

As temperature is increased above 124"F (the turnover cointi

(+0.5), the coefficient becomes negative (+0.5).

REFERENCE J.1 1.

General Electric Co. NTR SAR 4.7, p. 4-9.

QUESTION J.2 Could the NTR go critical with no water in the core? Exclain your answer.

(Consider physics, not administrative factors.)

(2.5)

ANSWER J.2 No. the reactor could not go critical. (+0.5) Void coefficient for the reactor is -5.7 t/1 void. (+0.5) Therefore. 100% void =

$5.70 negative. (+0.5) Even with all manual poison sheets removed and all rods out, the negative effect would be too much. (+1.0) e REFERENCE J.2 1.

General Electric Co. NTR SAR 4.7, pp. 4-10, 4-15.

-Section J Continued on Next Page-i

18 General Electric Co. NTR November 12, 1985 Points Available OUESTION J.3 Exolain the nuclear characteristics of the reactor that makes it a sensitive detector of reactivity changes.

Include the important features that enhance this performance.

(4.0)

ANSWER J.3 Several important features of the NTR that affect the nuclear characteristics result from an effort to enhance the performance of the reactor as a sensitive detector of reactivity changes.

Among these features are the low critical mass (+0.5), the fuel-to-samnle geometry (+0.5), and sensitive control system (+0.5).

The reactor is con.tructed so that samples glaced in the horizontal facility (+0.5) are in a neutron flux that is higher than the flux in the fuel lattice (+1.0).

The sensitivity of the reactor as a detector is nronortional to the ratio of the thermal flux at the samnle to that in the fuel lattice (+1.0).

REFERENCE J.3 1.

General Electric Co. NTR SAR 4.7, p. 4-9.

-Section J Continued on Next Page-

19 General Electric Co. NTR November 12, 1985 Points Available QUESTION J.4 List six (6) sources of reactivity changes at the NTR.

(3.0)

ANSWER J.4 Reactivity changes at NTR can occur from the following sources:

a.

Control or safety rod movement b.

Source movement c.

Manual poison sheet movement d.

Temperature coefficient e.

Void coefficient f.

Experiment changes g.

Fuel burnup h.

Poison buildup 1.

Graphite wetting J.

Mn RT* K MoveW MV (Any six [6] +9.5 each)

REFERENCE J.4 1.

NTR Requalification Program Examination C.1, p. 5.

QUESTION J.5 After an extended operation at full power, a scram occurs.

What would you expect to see whil( monitoring the nuclear instrumentation for the next 5 minutes?

(1.5)

ANSWER J.5 Prompt drop (+0.75) followed by an ~80-second negative period (+0.75).

REFERENCE J.5 1.

Stephenson, R., McGraw-Hill.

t

-Section J Continued on Next Page-l

20 General Electric Co. NTR November 12, 1985 Points Available OUESTION J.6 What is the maximum excess reactivity allowed by the NTR license including experiments?

(0.5)

ANSWER J.6

$0.76 (+0.5) l REFERENCE J.6 1.

General Electric NTR Tech. Spec. 3.1.3.1, p. 3-1.

QUESTION J.7 1

What neutron absorbing material is used in:

a.

the fine control rodf?

(0.5) b.

the coarse control rods?

(0.5) c.

the safety rods?

(0.5) d.

the poison sheets?

(0.5)

ANSWER J.7 a.

boron carbide b.

boron carbide c.

boron carbide

(+0.5 each) d.

cadmium REFERENCE J.7 1.

-General Electric Co. NTR SAR 4.6, p. 4-8.

1 i

i l

-Section J Continued on Next Page-l

21 General Electric Co. NTR November 12, 1985 Points Available OUESTION J.8 What are the tech. spec. values for the rate of withdrawal for the safety rods and the 7;L;are.g rods?

(1.0)

- latir c

-(

ANSWER J.8 Safety 1-1/4 inches per second (+0.5)

R^~M ating 1/6 inches per second (+0.5)

CANTKoL REFERENCE J.S 1.

General Electric Co. NTR Tech. Spec. 3.2.3.3 and 3.2.3.4, p. 3-3.

1

-Section J Continued on Next.Page-

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

22 General Electric Co. NTR November 12, 1985 Points Available DUESTION J.9 List six (6) NTR scrams and their set points.

(3.0)

ANSWER J.9 System Condition Trio Point Linear High reactor power

'129 m i20 W Loss of positive high E 0% ef eperating

(, yo y voltage to ion chambers volt y (if ion chambers are used)

Log N High reactor power 4138 kW

/ S o ""'

Short reactor period 2 'S saennds e 4 t re Amplifier mode switch NA not in operate position Loss of positive high 490% ef-cperetirig 5 70 V voltage to ion chambers mel tg.

(if ion chambers are used) o-Primary High core outlet 4222 F

/40

Coolant temperature Temperature Primary Low flow

+15 gp;;; when reactor i 7, 7 a F M Coolant Flow power is >0.1 kW Manual Console button depressed NA Electrical Reactor console key in NA Power off position Loss of ac power to console NA g

,y gg (Any six [6] +0.25 for condition, +0.25 for trip point.)

REFERENCE J.9 1.

General Electric Co. NTR SAR 8.3.2, p. 8-5.

-End of Section J-

23 Gen:ral Electric Co. NTR November 12, 1985 K.

FUEL HANDLING AND CORE PARAMETERS (22.0)

Points Available OUESTION K.1 Dran a sk f an axial view of the core. Shan the location of: The inlet, the water outlet, the safety rods, the fine control rod, and the coarse control rod.

(4.0)

ANSWER K.1 Attached

(+0.5 each) l REFERENCE K.1 G.E. NRT, SAR, p. 4-2.

I

-Section K Continued on Next Page-i k

m

l 24 General Electric Co. NTR November 12, 1985 Points Available ANSWER K.1 (continued)

E AST 4"a 4" HORIZONTAL PENETR ATiONS S ft a 5 ft Top RACE coR SULx EXPERIMENTS S feet I

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N \\.N. -

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s-wirs cR AaseTE insert ss s 3;s s. 'N

. s.

f(,

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@ WATER INLET

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ks 's' sN s's N

' l' "

O WATER OUTLET s

N. O

@ 1sArETv Roo

$:N;A,y'Rs; p. XJ s

s N

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@ ruEL oisx Nes' #i 'kh h.Sb'shkNN s'b'[\\-.

@ RA IUM-SERYLLiW SWRCE Roo w MANUAL Poison SHEET SLOT

@ EXPERIMENT TUJE FIGURE K.1 (AUSWER)

-Section K Continued on Next Page-

25 General Electric Co. NTR November 12, 1985 Points Available QUESTION K.2 E:< plain how a single fuel element is moved to the fuel storage tank for inspection.

Include any requirements associated with Procedure 4.3 (Reactor Refueling).

(4.0)

ANSWER _KJ2 f.

Assure that the fuel loading tank is filled with water.

2.

Verify that startup channel is responding to neutrons.

3.

Position the Reactor Cell Victoreen in the work area and set the alarm at.100 mR/hr.

s 4.

Determine neutron count rate of count rate channel,with fuel eter:ac rc;l ;; t,.

5.

Remove the graphite plug from the loading chute and place it c,in st' rage rack in fuel storage tank.

o 6.

Remove fuel element from reactor core. Monitor personnel dose rates and startup channel continously.

7.

Perform the inspection or dose rate measurement with the fuel element as deep in the tank as practical.

8.

Return the fuel element to its proper position in the core.

(+0.5each)

REFERENCE K.2 S0P 4.3, p.10.

l l

l s

l t

s

-Section K Continued on Next Page-

?

I

?

I

-+

,-e

26 General Electric Co. NTR November 12, 1985 Points Available OUESTION K.3 During reactor refueling a.

what is the maximum number of fuel elements that can be loaded in the first increment?

(1.0) b.

what is the maximum number of fuel elements that can be loaded in the second increment?

(1.0)

ANSWER K.3-a.

8 fuel elements

+1.0 b.

4 fuel elements

+1.0 REFERENCE K.3 S0P 4.3, pp. 6,7.

F 1

-Section K Continued on Next Page-l l

l 27 General Electric Co. NTR November 12, 1985 Points Available OUESTION K.4 Glyg a description of the Core Reel Drive Mechanism.

(4.0)

ANSWER K.4 Core Reel Drive (Rotating) Mechanism This mechanism consists essentially of two oinion gears (+1.0) keyed to a shaft. The shaft is sealed by a double 0-Ring and a " tattle-tale" drain cock is provided. The drive shaft extends from the core (where the pinion gears are mated with the spur gears of the core reel) through the reactor shield to the too of the fuel storage tank (+1.0) via a right angle gearbox to a hand ooerated control wheel.

(+1.0) A dial indicator. ad_iacent to the control wheel. indicated the oosition of the reel within the fuel can (+1.0) (and thus individual fuel assemblies also).

No other control for the mechanism is provided and therefore all changes of the reel positions must be accomplished from the top of the fuel storage tank during reactor shutdown.

REFERENCE K.4 S0P 4.3, p.2.

-Section K Continued on Next Page-

-.e

l 28 General Electric Co. NTR November 12, 1985 Points Available QUESTION K.5 Giye a description of an NTR fuel assembly.

(4.0)

ANSWER K.5 Each fuel assembly consists of 40 fuel disks and soacers (+1.0) skewered on a shaft to form a shishkabob-tyne assembly. (+1.0).

Lateral motion of the disks and soacers on the shaft is orevented by lock nuts olaced on both ends of the shaft (+1.0).

A 0.75-in. length of each end of the 0.5-in. aluminum support shaft is machined to provide a tip suitable for supporting and positioning the fuel assembly accurately in the core reel. (+1.0)

REFERENCE K.5 G.E. NTR, SAR, p. 4-5.

-Sectica K Continued on Next Page-

29 i

General Electric Co. NTR November 12, 1985 Points Available OUESTION K.6 Dran a sketch of an axial cross section of an NTR fuel disk

.and name the component parts. Dimensions are not required.

(4.0)

ANSWER K.6 2.751 SandWiCn bl.0) c 2.749 g Plates 0.517

[

0.51S h

DIAM h

Ill I{'

!.. ' k'*,_ f..ek;'i 'f I' l k

, 0,

0.210

• 2.;

&190

/','

j

,"p

( {

j(p' ' -

~

,vEMI.o)

O.032

+l.0) 0.022 INNER EDGE RING 0 I47

[.4 l. ( )

gg7 OUTER EDGE RING REFERENCE K.6 G.E. NTR, SAR, p.4-6.

-End of Section K-

30 General Electric Co. NTR November 12, 1985 L.

ADMINISTRATIVE PROCEDURES. CONDITIONS. AND LIMITATIONS _

(21.0) 4 Points Available OUESTION L.1 List the three (3) types of records that are to be retained for the lifetime of the NTR reactor facility.

(3.0)

ANSWER L.1 Records to be retained for the lifetime of the reactor facility.

(Note: Applicable annual reports, if they contain all of the required'information, may be used as records in this section.)

a.

Gaseous and liquid radioactive effluents released to the environs. (+1.0) b.

Radiation exposure for all personnel monitored. (+1.0) c.

Drawings of the reactor facility. (+1.0)

REFERENCE L.1 Technical Specification 6.6.3, p. 6-14.

I i

i

-Section L Continued on Next Page-

. ~. -,,-.

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

31 General Electric Co. NTR November 12, 1985 Points Available OUESTION L.2 What is the minimum required staffing when the reactor is nat secured?

(3.0)

ANSWER L.2 The minimum staffing when the reactor is not secured shall be composed of:

a.

A licensed operator in the control room. (+1.0) b.

A second person present at the site familiar with NTR Emergency Procedures and capable of carrying out facility written procedures. (+1.0) c.

A licensed Senior Reactor Operator shall be present at the NTR Facility or readily available on call. (+1.0)

REFERENCE L.2 Technical Specification 6.1.3.1, p. 6-3.

OUESTION L.3 Glyr the technical specification definition of an exoeriment.

(4.0)

ANSWER L.3 Any ooeration. hardware or target (+1.0) (excluding devices such as

~

detectors. foils. etc.) (+1.0), which is designed to investigate non-routine reactor characteristics or which is intended for irradiation (+1.0) in an experiment facility and which is not rigidly secured to a core or shield structure (+1.0) so as to be a part of their design.

REFERENCE L.3 Technical Specification Definition 1.5, p.1-1.

l~

-Section L Continued on Next Page-l

^

32 General Electric Co. NTR November 12, 1985 Points Available j

QUESTION L.4 What three (3) conditions must be satisfied in order for a senior reactor operator to be considered readily availabe on call?

(3.0)

AMSLER L.4 A senior reactor operator is readily available on call when all of the following conditions are satisfied:

a.

Is within a reasonable driving time (1/2 hour) from the reactor facility. (+1.0) b.

Can be promptly contacted by telephone. (+1.0) c.

Has informed the reactor operator on duty where he may be contacted. (+1.0)

REFERENCE L.4 Technical Specification Definition 1.22, p.1-5.

-Section L Continued on Next Page-

e 33 General Electric Co. NTR November 12, 1985 Points Available OUESTION L.5 List six (6) of the types of information that shall be included in the annual operating report submitted to the NRC.

(3.0)

ANSWER L.5 a.

A narrative summary of reactor operating experience including the hours the reactor was critical and total energy produced.

b.

The unscheduled shutdowns including, where applicable, cor-rective action taken to preclude recurrence.

c.

Tabulation of major preventive and corrective maintenance operations having safety significance.

d.

A summary report in accordance with 10CFR 50.59.

e.

A summary of the nature and amount of radioactive effluents release 3 or discharged to environs beyond the effective control of the owner-operator as determined at or before the point of such release or discharge.

f.

Summarized results of environmental surveys performed outside the facility.

g.

A summary of exposures received by facility personnel and visitors where such exposures are greater than 25% of that allowed or recommended.

Any six (6) (+0.5) each.

REFERENCE L.5 G.E. NTR Technical Specification Table 6.5.1, p. 6-10.

i I

l

-Section L Continued on Next Page-l

T 9'

34 General Electric Co. NTR November 12, 1985 Points Available OUESTICN L.6 Exclain the difference between a channel check and a channel

~

test.

(1.0)

ANSWER L.6 Channel Check A qualitative verification of acceptable performance by observation of channel behavior. This verification where possible shall include comparison' of the channel with other independent channels or systems measuring the same variable.

(+0.5)

Channel' Test The introduction or interruption of a signal into the channel to verify that it is operable.

(+0.5)

REFERENCE L.6 G.E. NTR Technical Specification Definition 1.3/1.4, p.1-1.

-Section L Continued on Next Page-

{

=

n n

35 General Electric Co. NTR November 12, 1985 Points Available OUESTION L.7 What conditions must'be satisfied for the reactor to be considered secured?

(4.0)

ANSWER L.7 The reactor is considered secured under either of the following two (2) conditions:

1.

The core contains insufficient fissile material to attain criticality under optimum conditions of moderation and reflection. (+1.0) 2.

When all the following conditions are satisfied a.

Reactor is shut down. (+1.0) b.

Console keylock switch is 0FF and the console key is in proper custody. (+1.0) c.

No work is in progress involving in-core components, installed rod drives, or experimer.ts. (+1.0)

REFERENCE L.7 Technical Specification 1.20, p. 1-4.

-End of Section L-

-END OF EXAM-t l

7-

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= -AN de

~

N = N,e HVL = 0.693/p g

t = 0.693/A N - S/1-Keff P = P e /'

t A = AN o

A = A,e" P = P,(10 ' ")

E

• I

- *~

P"

+

rate iAz e

Indg 2"1d 2 2 R/hr 9 1 foot = 6 CE I = I,e "*

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CR (1-K f f ) = CR (1-K'f f '

g 2

2 a-

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