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Exam Rept 50-288/OL-87-01 Administered on 870519-22.Exam Results:Four Senior Reactor Operators (Sros) Passed Written Exam,One SRO & All Reactor Operators (Ros) Failed Respective Written Exam & One RO Failed Operating Portion
	ML20235E523
Person / Time
Site:	Reed College
Issue date:	06/19/1987
From:	Elin J, Meadows T; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:	;
Shared Package
ML20235E508	List: ML20235E505; ML20235E523;
References
	50-288-OL-87-01, 50-288-OL-87-1, NUDOCS 8707110097
	Download: ML20235E523 (160)
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U. S. NUCLEAR REGULATORY COMMISSION ,

REGION V l EXAMINATION REPORT Examination Report No.: 50-288/0L-87-01 i

Facility Licensee: Reed Reactor Facility Reed College l Portland, Oregon 97202 I 1

l Facility Docket No.: 50-288 Facility License No.: R-112 I Examinations administered at Reed College, Portland, Oregon Chief Examiner: .-:M~ 4 mum ~ c - o"- r 7 Thomas R. Meadows Date Signed h-/ 7 - M Approved by: -

hn 0. Elin, Chief, Operations Section Date Signed Summary:

I Written examinations were administered to four R0 candidates and five SR0 candidates on May 19, 1987. The operating examinations were administered May 20-22, 1987. Four SR0 candidates passed the written examination. The other SR0 candidate, and all of the R0 candidates failed their respective written examinations. One R0 candidate failed the operating portion of the examination, while all others (R0's and SR0's) passed. Licenses were issued to four SR0 candidates.

8707110097 870623 PDR ADOCK 05000288 y PDR

REPORT DETAILS

1. Examiners

Thomas Meadows, RV Gary Johnston, RV

Chief Examiner

2. Persons Attending the Exit Meeting:

T. Meadows, RV, Chief Examiner G. Johnston, RV M. Pollock, Director, Reed Reactor Facility

_Allana Boland, Senior Reactor Operator 3 (Supervisor, Reed Reactor Facility)

3. Written Examination and Facility Review:

Written examinations were administered at Reed College on May 19, 1987.

The examination implementation and facility support was . satisfactory.

The Chief Examiner met with Dr. Larry Church, Senior Reactor Operator and former Reactor Director, following the examination on May 21, 1987 to conduct the exam review. Facility generated comments were formalized, endorsed by the Vice President, Provost, Dr. Marshall Cronyn, and subsequently forwarded to Region V. The NRC resolutions of these comments are attached for both the R0 and SR0 examinations, respectively (Attachments 1 and 2). Deficiencies associated with the facility's inadequate reference material, and operator training program were discussed at the exit meeting.

4. The examiners, during the review of graded examinations noted two areas of poor or inadequate operator training. These areas were the principles of reactor operation or reactor theory and radiation control and safety.

In the principles of reactor operation or reactor theory portion of the written examinations only one SR0 candidate scored above 80%, while two candidates failed with grades less than 70%. In the radiation control and safety portion of the R0 written examination, no candidate was able to achieve a passing grade of 70%. It was particularly noted that a question on reduction of a dose rate from a point source as the distance from the source is increased was missed by all candidates. This question addresses basic principles of radiation safety and therefore, total failure on this topic by all candidates clearly indicates an inadequacy in training on radiation safety.

5. Operating Examination:

The operating examinations were administered May 20-22, 1987.

General training weaknesses were discovered in the operation of the facilities irradiation facility and in the use of portable radiation monitoring equipment. These concerns were discussed at the exit meeting.

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6. Exit Meeting:

On May 22, 19C7, the Chief Examiner met with the licensee representatives j listed in paragraph 2. l The Chief Examiner expressed the following concerns:

a. The review of operating procedures and technical reference material for accuracy appears to have broken down. Discrepancies were identified in the supplied reference material during written 1 examination preparation, and the subsequent review with the facility, i In some cases technical information was wrong or not reflective i of actual facility conditions. In other cases, material was either (

not supplied or supplied in an inadequate depth to fully describe 'l the facility. For example, no information was supplied that described the portable radiation monitoring used at Reed.

Operating procedures provided by the facility were inconsistent in their format and occasionally inadequate in their detail.

In some cases the operating procedures spscified a general condition to be achieved without detailed instructions as to how to achieve these desired conditions. The operating procedures were additionally found, in several instances, to be inconsistent with other technical reference material supplied by the facility.

These reference material deficiencies resulted in a large number of facility comments during the review of the written examinations.

The facility staff recognized the reference material deficiencies detailed by the Chief Examiner and committed to review and upgrade their reference material.

b. During the oral portion of the examination the NRC team discovered that the operator candidates had not been adequately trained on, i nor ever operated the facility's irradiation transfer system (RABBITOperations). The Chief Examiner explained that the operation of systems that could affect the reactivity of the reactor core, or had the potential for causing a radiological incident should be mastered by facility licensed operators. The facility staff committed to upgrading their reactor training program to include rabbit operations.

c. The NRC examination team found that their candidates were not l familiar with the operation of alpha or neutron portable i radiation monitoring equipment. Subsequently, the examination 1 team found that these instruments were not available on site. )

The facility staff committed to obtaining both alpha and neutron portable monitoring equipment and implementing appropriate ,

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ATTACHMENT 1 REED COLLEGE REACTOR FACILITY COMMENTS AND NRC RESOLUTIONS MAY 19, 1987 RO EXAM QUESTION A.6.(c) and (d)

COMMENT:

The expression "Xe-transient" is not used in.the sections of the Training Manual referenced by the examiner and is not familiar to the reviewers. One of the reviewers (Grant) believed this question to refer to the xenon build-up which occurred between shutdown and restart and would have answered part c about maximum rod movement to occur during the withdrawal of the control rods on restart. This interpretation results in the answer to (d).

being OUT. The other reviewer (Church) interpreted the term to refer the removal of Xe after restart (as did the examiner), however, he believes that the max. removal of Xe (which yields maximum control rod motion) would occur l

immediately after reaching full power on restart rather than over an

apparently arbitrary time of 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months .

References available to the trainees differ on the exact time after shutdown when the Xe peak is reached, however,the primary reference, the Training Manual, Module 12-7, p. 24-25 places the peak in excess of 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months after

, shutdown.

SUGGESTED RESOLUTION:

For(c): Accept answers which indicate that the examinee has knowledge of Xe poisoning; For (d) accept the answer which is most consistent with the examineesanswerto(c).

NRC RESOLUTION: Comment not accepted.

The answer key is consistent with reference material supplied by facility.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as as specified in NUREG 1021. ES-108, Examiners Standard. No change to the answer key is necessary.

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QUESTION A.7 COMMENT:

The answer to this question could also be phrased to state that burnable poisons may be placed in fuel to help keep the core excess more constant in the immediate time after adding new fuel. No documentation exists that the fuel in the Reed Reactor, as delivered, actually ever contained burnable i poisons and the trainees were so instructed in discussions of fuel poisons. ]

I SUGGESTED RESOLUTION: l I

Accept answers, including that in the key, which provide evidence that the examinee understands burnable poisons including samarium.

NRC RESOLUTION:

Comment not accepted. I 1

The question is consistent with facility supplied reference material. The j answer key adequately supports the call of the question.

QUESTION B.1 I COMMELT:

The figure used in this question is of a generic TRIGA tank; not the Reed Reactor and the orientation of several items is different. Individuals taking the exam may have tried to specify neutron detectors (ie. Fission, CIC, %

Power, etc.) in response to Part C and their answers would be affected by which component they took to be " correctly" located.

SUGGESTED RESOLUTION:

Acceptable answers to C. should include any answers which indicate that the operator recognized the component as a neutron detecting chamber; all other sections OK.

I NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with facility supplied reference material and ;

clearly indicates that any type of " detector" would be acceptable for part (c). l i

R QUESTION B.2 COMMENT:

l The Central thimble at the Reed Reactor is water filled except during Special Experiments when it can be voided with gas to produce a neutron beam. This has not been done since the early 1970's. Even when voided, the thimble within the core contains water to a point above the top grip plate. It may i also be used when filled with water as an irradiation facility and it is the

! position with the maximum neutron flux. In most references to this facility it is called the Central Thimble (eg. Administrative Procedures. Section 4.1). i SUGGESTED RESOLUTION:

l None required. j NRC RESOLUTION: q l

Same as Question A.7 1 QUESTIONB.4(a],

COMMENT:

This is commonly referred to as the Bottom Pin.

SUGGESTED RESOLUTION:

Accept either term. ,

NRC RESOLUTION:

Comment not accepted.

Any reasonable statement that positively identified the component would k be accepted; therefore, no change to the answer key is necessary. j i

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QUESTION B.7(a)

COMMENT: l In addition to the function listed in the key, the same section of the reference used by the examiner contains the statement that low conductivity of the primary system is important to " minimize corrosion of all reactor components, particularly the fuel elements." It is also stated the primary water system reduces radioactivity in the water by removing nearly all particulate and soluble impurities which is another reason for knowing the conductivity.

1 SUGGESTED RESOLUTION: i Accept either of the above functions or the function listed in the key.

NRC RESOLUTION:

Comment not accepted.

I The answer key is consistent with facility supplied reference material and meets the call of the question. The question does _not ask for the function of the water purification system.

C.1.(b) COMMENT:

The phrase " Cells and Inhomogeneities" is not used in training operators and could not be located by the reviewers in any of the facility references supplied for the exam. The potential confusion of examinees may have been reduced by the inclusion of ZrH x in the question.

SUGGESTED RESOLUTION: 1 1

None required.

NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by facility.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

l QUESTION C.2 COMMENT:

See C.1.

NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by facility Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

QUESTION C.4 COMMENT:

During operation of the reactor, control rod worths are most often given in dollars. The actual values for these rods after construction of the reactor were about $4.25 for the shim and safety rods and $1.50 for the regulating rod. These values differ from the design values given in the SAR.

SUGGESTED RESOLUTION:

Accept values in dollars as given or values from the SAR.

NRC RESOLUTION:

Comment accepted.

In response to new information provided by the facility, the answer-key will be modified to include these values, as a group, as an alternate acceptable answer.

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QUESTION C.5(c)

COMMENT:

In addition to the reasons given in the key, the Mechanical Maintenance Manual discusses the necessity for water to be as deep as the control rod barrels to insure proper dash-pot action. (Ref.Section3). The depth of water above the top grid plate to the dash-pots is 16 feet; the distance to l the skimmer is 20 feet (Mechanical Maintenance Manual pages 7, 20, 73, 81).

e In evaluations of the facility related to revisions to the Technical )

l Specifications it has been determined that dash-pot action is the limiting {'

condition on water depth.

SUGGESTED RESOLUTION:

Accept reasonable answers for reason why the water depth should be 16 feet.

NRC RESOLUTION:

1 Comment accepted.

The answer key is modified to accept:

"To insure that proper dash-pot action occurs for the control rod barrerls" - 1 as an acceptable response worth 0.5 points; however, question C.5(c) will ;

remain 1.0 point (maximum) overall.

QUESTION C.8 ,

The Emergency Implementation Procedures include (in an appendix) values of " Normal" instrument levels for use in the evaluation of emergencies after j they occur when a " normal" reading might be difficult to obtain. It is not intended that these values be memorized. The actual " normal" values cover a significant range of values as follows:~

CAM 50-500 cpm (depending on seasonal variations in radon levels)

RAM 0.05-0.15 mr/hr Secondary Water Pressure: 60-90 psi (depending on how clean the filter baskets are.

i SUGGESTED RESOLUTION:

Accept values within the ranges given.

NRC RESOLUTION:

Comment accepted.

Acceptable ranges were not provided with the facility reference material used to prepare this examination. The answer key is modified to incorporate the ranges given above as acceptable answers.

QUESTION D.3 COMMENT:

The neutron source installed in the Reed Reactor is an AmBe source (ref.

License Section 2.C). We are also licensed to possess and use a PuBe source (ref. License 2.B.) which was used at low powers as a start-up source for about 1 year until the AmBe source reached a sufficient neutron emanation rate for use as the sole start-up source. The PuBe source was then removed (about 1969) and remains in storage.

SUGGESTED RESOLUTION:

Correct the key to reflect that the source is AmBe.

NRC RESOLUTION:

Comment accepted. J Am-Be was added to the answer key as an acceptable source.

QUESTION E.3 I

COMMENTS:

Set points on these monitors may change during calibrations every six months and following maintenance operations. They may also be changed if there is ,

a change in background levels as occur with seasonal variations in radon concentrations. The values quoted by the examiner from the EIP are there for planning purposes only and should probably have been clearly labeled as such.

The values on the CAM and the RAM however, have not changed recently and examinees should have given answers close to the values given in the key, l

SUGGESTED RESOLUTION:

None required.

NRC RESOLUTION:

Comment not accepted.

The question is consistent with facility supplied reference material. The answer key adequately supports the call of the question.

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i QUESTION E.4(b)

COMMENT:

The facility license does not allow operation for testing; this is found in the Technical Specifications which are incorporated-into the License by reference. Reed's NRC project manager has notified us that any. operation above 250 KW is a violation of the License, Tech. Specs not withstanding.

This condition apparently applies to all TRIGA reactors and invalidates this provision. We are negotiating for a resolution of this conflict in our i

proposed _ Technical Specifications, however, it is unclear what NRC's position will be. It is unknown to what extent the license candidates are aware of.

this situation.

I SUGGESTED RESOLUTION:

1 Accept either 250 KW or 287.5 KW.

NRC RESOLUTION:

Comment accepted. :

The answer key is modified to accept 250 KW as an acceptable response to Question E.4.b. This is another example of the inconsistent (in-adequate) reference material supplied for-this examination.

i QUESTIONSF.3(b)andF.5(b)

COMMENT:

When these SOP's were developed, we were not aware that statements designed to encourage operators to be careful operating the reactor would become information to be memorized verbatim for NRC exams. 50P-03 guides operators to " ease off the shim rod" when reactor periods reach 15 secs. SOP-05 states that operators should raise the shim rod carefully to achieve a period more than 10 secs. It then goes on to say "the less familiar the operator is with ,

the facility the longer the period should be . When we revise these 50P's we j will be careful to remove such discrepancies. '

J SUGGESTED RESOLUTION:

Accept reasonable periods for each of these questions.

NRC RESOLUTION: j Comment accepted.

The answer key is consistent with supplied facility reference materials; however, since it was the intention of the examiner and the answer-key to accept " reasonable periods", the key is modified to clearly indicate the range of acceptable periods. Any response falling outside this range will not be accepted.

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QUESTION G.3 Thin window G.M. Monitoring ir.struments such as the Ludlum detect beta and gamma radiation, not just gamma.

SUGGESTED RESOLUTION:

Change the key.

NRC RESOLUTION: ;

Comment accepted. ,

1 Consistent with newly supplied facility reference material, the answer-key is !

modified to accept " gamma and beta" as the acceptable answer.

QUESTION G.4 COMMENT:

Unfair question; we hes.e no partable neutron monitors.

NRC RESOLUTION:

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Comment accepted. i The question is consistent with TRIGA generic reference material available for portable neutron detectors. However, upon site review of the portable radiation monitoring equipment actually available at Reed, this question was reevaluated for its objectiveness. This question is deleted from this examination.

QUESTION G.8 Regardless of the 50P (the reviewer was unable to locate such a statement in the referenced SOP), no smoking, eating, or drinking is permitted in the facility regardless of the two conditicns listed in the key.

SUGGESTED RESOLUTION: 1 An answer that "No Smoking, Eating, or Drinking is permitted in the facility" should be accepted.

NRC RESOLUTION:

Comment not accepted.

The question clearly references material supplied by the facility,

" Radiological Safety Rules", as the guidance for not smoking, eating, and drinking around radioactive materials. The Reed Facility's policy of not allowing these practices within the facility has no bearing on the call of the question; and furthermore, was not identified in the supplied facility reference material.

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I ATTACHMENT 2 i

REED REACTOR FACILITY COMMENTS AND NRC RESOLUTIONS "

MAY 19, 1987 SR0 EXAM l

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QUESTION H.1 COMMENT:

The neutron source installed in the Read Reactor is an AmBe source (reference License section 2.C.). We are also licensed to possess and use a PuBe source (reference. License 2.B.) which was used at low powers t.s a start-up source for about 1 year until the AmBe source reached a sufficient neutron emanation rate for use as the sole start-up source. The PuBe source was then removed (about 1969) to and remains in storage.

SUGGESTED RESOLUTION: )

1 Correct the key to reflect that the source is AmBe. I NRC RESOLUTION:

1 Conenent accepted. l l

The answer key is modified to accept Am-Be as an acceptable response, l corresponding to newly suppled facility references. i 1

QUESTION H.3 COMMENT:

The phrase " Cell and Inhomogeneities" is not used in training operators and could not be located in any of the supporting documents provided by the facility. This portion of the Fuel Temperature Coefficient is always referred to as Zirconium Hydride (ZrH question on the R0 exam (C.1(b)) andthe in)SAR, as used by the Appendix examiner E, Core in a similar Physics.

The term, as used in the question, may be unfamiliar to examinees. This substitution of terms potentially compromises the entire question.

SUGGESTED RESOLUTION:

Accept answers which accurately discuss some aspect of the negative temperature coefficient.

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i NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

QUESTION H.4 COMMENT:

This problem contains three areas of concern to the reviewers:

1. The problem was taken by the examiner from the Training Manual in a section which contains several errors. This section of the Manual reverses the terms micro and macroscopic cross-section.

2. The answer key (and the Training Manual) contain additional errors in l i

the calculation equation) including which should the number be 22.923 X 10 g;Second, atoms (where it appears in the manual the in the microscopic and macroscopic cross-sections are reversed in several parts of the discussion.

3. The reference material provided by the facility in preparation for the I

exam includes information on reactor theory as requested by the licensing section of NRC. We feel we have done the best job possible in selecting information applicable to our facility without having to write our own reactor physics text book. The manual, of necessity, contains some material which is not directly applicable to our facility and its operators, and it is designed to serve as reference material which operators can use subsequent to receiving their licenses. We do not have any beam neutron beam ports in use at the facility and do not ;

conduct experiments on neutron absorption in beams. We do discuss l those sections of this Training Module related to the activation of materials in the reactor and the meaning of neutron cross section in ;

that context. The question as worded is probably unfamiliar, except in i general terms, to the examinees.

SUGGESTED RESOLUTION:

Correct the arithmetic error; accept answers which indicate that the I examinees have a knowledge of the meaning of neutron cross-sections. I l

NRC RESOLUTION:

Comment accepted.

The calculational errors identified in the facility supplied references l are corrected in the answer key. Furthermore, the answer key is modified i to clarify that the answer in terms of " Barns" would be an acceptable response. The candidates are expected to know the difference between

" micro " and macro " scopic cross section despite the inconsistency identified in the facility supplied reference material.

QUESTION H.5 COMMENT:

We do not use, nor is it appropriate to use with our reactor, the term decade. Some operators may be aware of this power reactor term, others may

, quite reasonably assume that two decades means 20.

1 SUGGESTED RESOLUTION:

Accept answers which correctly calculate the time using a power increase factor of either 20 or 100.

NRC RESOLUTION:

Comment accepted.

Reference material supplied did not address the term " decade". Since it is the intention of the question to examine the candidate's correct application of operational physics, the answer key is nodified to accept a power ratio of 20 if it is applied correctly in the response.

QUESTION H.6 COMMENT:

The expression " Start Up Rate" is not contained in the facility document referenced by the examiner, and is not appropriate nor used at Reed. The change in reactor power with time at Reed is defined in terms of " Period". The question was not understood by the reviewer and probably will not be understood by the examinees. The expression SUR in the answer is likewise not contained in the facility references and is unknown to the reviewer. Not being familiar with these terms, examinees are likely to have equated it with reactor period and attempted to answer the question in those terms.

SUGGESTED RESOLUTION:

Accept answers which correctly deal with the question of a reactor Period or prompt period resulting from the given reactivity insertion.

NRC RESOLUTION:

Comment not accepted.

Reference material supplied did not address the term start up rate.

The answer key, however, is consistent with stated references (Stephenson, R.

McGraw-Hill and the Equation Sheet), which identifies the relationship between SUR and period. Correct application of the period equation, as supplied in the examination, would also be accepted. No change to the answer key is necessary.

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QUESTION H.8 COMMENT:

Again, -1/3 DPM SUR, in the question is not a familiar term to the reviewer; however, the question should be answerable if this is ignored.

SUGGESTED RESOLUTION:

None required; accept answer in key.

NRC RESOLUTION:

Comment not accepted.

Reference material supplied did not address the term start up rate.

The answer key, however, is consistent with stated references (Stephenson, R.

McGraw-Hill and the Equation Sheet), which identifies the relationship between SUR and period. Correct application of the period equation, as supplied in the examination, would also be accepted. No change to the answer key is necessary.

QUESTION H.9 COMMENT:

1 The answer to his question could also be phrased to state that burnable i poisons may be placed in fuel to help keep the core excess more constant i in the immediate time after adding new fuel. No documentation exists that the rule in the Reed Reactor, as delivered, actually ever contained '

burnable poisons and the trainees were so instructed in discussions of l fuel poisons. .

SUGGESTED RESOLUTION:

Accept answers, including that in the key, which provide evidence that the examinee understands burnable poisons including samarium.

NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be coraistent for each candidate as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

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QUESTION H.10 (d) and (e)

COMMENT: 1 The expression "Xe-transient" is not used in the sections of the Training i Manual referenced by the examiner and is not familiar to the reviewers. j One of the reviewers (Grant) believed this question to refer to the xenon J build-up which occurred between shutdown and restart and would have answered the question about maximum rod movement to occur during the withdrawal of the control rods on restart. This interpretation results in the answer to (e)beingOUT. The other reviewer (Church) interpreted the term to refer to the removal of Xe after restart (as did the examiner), however, he believes that the maximum removal of Xe (which yields maximum control rod motion) would occur immediately after reaching full power on restart rather than over an apparently arbitrary time of 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months .

There is a discrepancy between the question and graph provided in the exam with respect to tiie time of restart. 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months vs. 80.s hours, which may influence details in the answers to the question. References available to the trainees differ on the exact time after shutdown when the Xe peak is reached, however the primary reference, the Training Manual, Module 12-7, page 24-25 places the peak in excess of 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months after shutdown.

SUGGESTED RESOLUTION:

For(d): Accept answers which indicate that the examinee has knowledge of Xe poisoning; For (e) acce examinees answer to (d)pt the answer which is most consistent with the NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as specified in NUREG 1021, ES-108, Examiners l Standard. No change to the answer key is nectssary. {

i Futhermore, answer key parts (b), (c) ano (d) reflect acceptable ranges of !

acceptable responses to the associated question, which eliminates the above concerns on possible time discrepancies. Furthermore, the time frame indicated (82-87 hours) for part (d) would be the maximum removal of Xenon due to decay after MAX PEAK and burn-out upon restart. Adequate knowledge of operational physics would eliminate confusion of the appropriate countering rod motion.

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'I QUESTION 1.1.c(1)

COMMENT:

Answer should read 0.5 rem not Mrem.(10 CFR 20.105)

SUGGESTED RESOLUTION:

Correct key.

NRC RESOLUTION:

Comment accepted.

l The answer key is modified to correct typo.

QUESTION I.3(b)

COMMENT:

The (R=6CEn) equation provided is a very approximate relationship which we use to estimate gamma dose rates. The way the question is worded, it i appears that the examiner wants an exact calculation. The words "about" or l "approximately" should have been included.

1 SUGGESTED RESOLUTION:

Accept the answer in the key or a reasonable attempt to calculate a more precise value. <

l NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

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QUESTION I.4 1

COMMENT-i The reviewer doesn't expect the examinees to have memorized the G.E. Chart of the Nuclides and to know the fine points of the decay schemes of 2 i (admittedly common) nuclides is not a reasonable question. J SUGGESTED RESOLUTION:

Accept the answer in the key.

NRC RESOLUTION: l 1

Resolution accepted.

The question is adequately discriminant without requiring candidates to l

" memorize" the G.E. chart of the nuclides. 4 l

I QUESTION I.5 Quality Factors (RBE's) for neutrons vary with energy and between references for alpha particles. (eg. Friedlander, Kennedy, Miller, Nuclear and Radiochemistry, P.126 (copy attached); Note: this is the text which is used for the Nuclear Chemistry class which several of the examinees have taken.

SUGGESTED RESOLUTION:

Accept either those values from the training manual or Friedlander, Kennedy, and Miller.

NRC RESOLUTION:

Comment accepted.

The answer key is modified to accept the new information supplied by the faci'lity is as an acceptable response.

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l QUESTION I.8 COMMENTS: )

a. According to the 50P referenced by the examiner, the Ra226 source is not used to calibrate the beta sensitive CAM, only to provide sufficient count rate to allow adjustment of failsafe and alarm set points.

Although this question may confuse some examinees, the correct answer is gamma.

b. Since the uranium oxide sources are covered with a polyethylene and scotch tape window, no alpha's are seen by the GM. The correct answer is beta and some gamma.

SUGGESTED RESOLUTION:

Correct answer key for (b).

NRC RESOLUTION:

Comment accepted.

a. The Ra-226 source is used to calibrate the CAM, and it does adjustment 1 of the alarm setpoTKt for gamma. No " confusion" should result from this. <

b. The answer key is corrected to accept beta and gamma as the correct response for part (b) in-lieu of alpha; thereby correcting the confusion generated by the facility supplied reference material.

l QUESTION I.9 I

COMMENT:

Since Reed has not been operational for 2 years and since it does not have any DOT shipping containers, no transfers have been recently made. The reviewer believes that this type of information contained in this question l should be read when needed rather than memorized. Examinees should be familiar with the existence and basic principles of this S0P but are probably not familar with the details. (d) 10 mR/hr at surface (?)

SUGGESTED RESOLUTION:

Accept answers which indicate a knowledge of general aspects of the Transfer of Materials 50P.

NRC RESOLUTION:

Comment accepted.

Upon site review of the facilities transfer procedures and implementation, this question was reevaluated for its objectiveness. This question is deleted from this examination.

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QUESTION J.3(b)

COMMENT:

Poorly worded question. As worded, any reasonable operator under ,any

" operating condition" would ease off the shim rod up button when a period of less than 15 sec. is achieved. The sentence referenced by the examiner is taken out of the context of the SOP.

SUGGESTED RESOLUTION:

Accept the answer given in the key or an answer which indicates that examinee recognizes the need to exercise caution with short reactor periods.

NRC RESOLUTION:

Comment not accepted.

The question is consistent with the facility supplied reference material, which specifically identifies an operational condition (subcritical to supercritical) in which action must be taken to present short periods. This sentence is not taken out of context, and subsequent changes to the answer key are not necessary.

QUESITON J.6 COMMENT:

The three required SCRAMS for the Reed Reactor Facility are listed in the Technical Specifications as:

1. Linear

2. Percent Power 1 3. Scram button on console (Manual).

The three additional scrams are referred to as the Period Scram, High Voltage Scram, and External (loss of console power) Scram (TRIGA MARK I Reactor I Instrumentation Maintenance Mar.ual, Chapter 1, Description, page 1-4). These are the terms commonly used for the scrams on the reactor rather than those included in the Safety Analysis Report. The terms used for the scram listed in question J.6.(1) are not in common use and may not be recognized as the linear power channel scram by examinees, i SUGGESTED RESOLUTION: j Accept answers which correctly identify the six scrams by either of the l lists of names used above.

NRC RES0_LUTION:

Comment accepted.

The answer key is consistent with the facility supplied references. However, !

the answer key is adjusted to accommodate the discrepancy in the supplied reference materials by incorporating the alternate scram names, stated above, into an appropriate place on the key for acceptable alternate responses, i

QUESTION E7 M COMMENT:

The Technical Specification setpoint is 2 cps; actual setpoints vary and *.re >

currently 5-6 cps. This channel is normally referred to as the Count-rcte l Channel. l l

SUGGESTED RESOLUTION:

Operators should have recognized that the answer to the question should have included the Tech. Spec. limit; accept answer in key.

NRC RESOLUTION:

Comment not accepted.

The answer is consistent with facility supplied reference material. New reference was not supplied by the facility to validate this concern.

QUESTION K.1 COMMENTS:

Set points on these monitors change every six months and following maintenance operations. They may also be changed if there is a change in background levels as occur with seasonal variations in radon concentrations.

The values quoted by the examiner from the EIP are there for planning purposes only and should probably be clearly labeled as such. Ranges of values from recent calibrations are as follows:

CAM: 2000 cpm RAM: 2 mr/hr GSM: 115-160 cpm APM: 1200-1800 cpm SUGGESTED RESOLUTION:

Accept values within the ranges given.

NRC RESOLUTION:

Comment accepted.

Recent calibration documentation, nor acceptable alarm setpoint ranges were provided in the facility supplied reference materials; however, the answer key is modified to accept the resonable ranges from the GSM and APM stated above.

QUESTION K.3 COMMENT:

In addition to the function listed in the key, the same section of the reference used by the examiner contains the statement that the low conductivity of the primary system is important to minimize corrosion of all reactor components, particularly the fuel elements. It is also stated the primary water system reduces radioactivity in the water by removing nearly all particulate and soluble impurities and this provides an additional reason to monitor the conductivity.

SyGESTEDRESOLUTION:

Accept either of the above functions or the function listed in the key.

NRC RESOLUTION:

Comment not accepted.

The answer key is consistent with the facility supplied reference and meet the call of the question. The question does not ask for the function of the entire water purificant system.

QUESTION K.4 COMMENTS:

The question is confusing with regards to vertical, horizontal, axial, and radial.

S,!JGGESTED RESOLUTION:

Examinees should have identified the graphite in the fuel elements and the reflector as the components providing reflector for the core. Accept answers which reflect this knowledge.

NRC RESOLUTION:

Comment not accepted.

Both questions (a) and (b) clearly specify what is ment by the vertical (axial) and/or horizontal (radial) direction; therefore, it is not necessary to alter the answer key.

i

QUESTION K.5(a)

COMMENT:

The reflector sits on four feet rather than directly on the bottom of the pool (reference: R0ExamKey,QuestionB.3.(c)).

SUGGESTED RESOLUTION:

Correct key.

NRC RESOLUTION:

Comment not accepted.

l The answer key is consistent with the facility supplied references in that the reflector does rest on the pool bottom via four support feet.

Modification of the answer key is not necessary.

QUESTION K.5.(c)

COMMENT:

Presumably the examiner includes natural convection in his answer.

SUGGESTED RESOLUTION:

No change in key required.

NRC RESOLUTION:

Resolution accepted.

l The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as specified in NUREG 1021 ES-108, Examiners Standard. No change to the answer key is necessary.

l I

i I

QUESTION K.7 COMMENT:

During operatior of the reactor, control rod worths are most often given in j dollars. The actual values for these rods after construction of the reactor '

were above $4.25 for the shim and safety rods and $1.50 for the regulating rod rather than the design values given in the SAR.

SUGGESTED RESOLUTION:

Accept answers in dollars.

NRC RESOLUTION:

Comment accepted.

The answer key is modified to accept the response indicated above, consistent with new operational documentation supplied by the facility.

QUESTION K.9.(b)

COMMENT:

In addition to the reasons given in the key, the Mechanical Maintenance Manual j discusses the necessity for water to be as deep as the control rod barrels to J insure proper dash-pot action. (

Reference:

Section 3). The depth of water above the top grid plate to the dash-pots is 16 feet; the distance to the skimmer is 20 feet (Mechanical Maintenance Manual pages 7,20,73,81). In evaluations of the facility related to revisions to the Technical Specifications it has been determined that this is the limiting condition on l water depth.

SUGGESTED RESOLUTION: )

Accept reasonable answers for the reason for water depth.

NRC RESOLUTION:

Comment accepted.

The answer key is modified to accept, "to insure that proper dash-pot action occurs for the control rod barrels," as an acceptable response for 0.5 points; however, the overall point value that will be awarded for Part (b) will remain (1.0).

1 i

QUESTION L.3 COMMENT:

Although the NRC requires that the term " Emergency Planning Zone" appear in the E-Plan for the reactor facility, it is a meaningless term for our facility. Unlike a power reactor where the EPZ in outside of all areas of operation, the only area of the Reed Reactor facility which technically meets the NRC definition of an EPZ is a portion of the reactor bay.

Emergency Planning, however, extends beyond to Reactor Bay to the entire facility, facility site, and, in the case of a potential fire in the Chemistry Building (which is believed to be the serious emergency with the highest probability), to the entire Chemistry Building and beyond.

The statement from which the examiner took the answer in the key actually states that the EPZ is equivalent to the " operations boundary" which is a term defined in section 2 of the E-Plan to include different areas under different conditions. Each of these is indicated to require planning.

The Reed Reactor Safety Committee has recently conducted an audit of this plan and identified tne questions of boundaries as a major item needing revision.

SUGGESTED RESOLUTION:

Review the examinees answer for an understanding of the seriousness of Emergency Planning which is the reason for having something called a planning zone in the first place.

NRC RESOLUTION:

I Comment not accepted.

The answer key is consistent with reference material supplied by Reed.

Partial credit will be awarded if the candidate applies his knowledge correctly and clearly states his assumptions. Awarding of partial credit must be consistent for each candidate as specified in NUREG 1021, ES-108, Examiners Standard. No change to the answer key is necessary.

I 1

l l

t

QUESTION L.4 COMMENT:

The facility license does not allow operation for testing as indicated in this question; this is found in the Technical Specifications which are incorporated into the License by re.%rence. Reed's NRC project manager has notified us that any operation above 250 KW is a violation of the License, Tech. Specs not withstanding. i.is k condition apparently applies to all TRIGA reactors and invalidates this prevision. We are negotiating for a resolution of this conflict in our proposed Technical Specifications, however, it is unclear what NRC's position will be. It is unknown to what I

extent the license candidates are aware of this situation.

SUGGESTED RESOLUTION:

Accept either 250 KW or 287.5 KW.

NRC RESOLUTION:

Comment accepted.

The answer key is modified to accept, "250 KW", as an alternate response for part (b), accommodating the inconsistencies identified in the facility supplied reference material.

QUESTION L.8 COMMENTS:

a. The ROC is composed of at least four members of the Reed College faculty and facility staff.

I

b. The administrative procedures referenced by the examiner do not specify to which the committee reports. The Radiation Safety Committee reports to the President (reference: Admin. Proc., page 6-8). It is implied on Figure 2-1 Administrative Procedures that the Committee communicates with the Director and the Health Physicist and this may be interpreted by some to imply reports to upper level management of Reed College expressed by the NRC, both Committees have made a practice this year of reporting to the President as well as the Director.

c. Both committees are operating under charters which require quarterly meetings pending resolution of proposed Technical Specifications.

SUGGESTED RESOLUTION:

Accept either President or Director for (b); others as in key.

1 i

1 1

NRC RESOLUTION:

Comment accepted.

The answer key is modified to accept, Director", as an alternate I response for part (b), accommodating the inconsistencies identified in the facility supplied reference material.

I I

l QUESTION L.9 ]

The E-Plan (Section 3.5) states " exposure limits are 75 rem whole body for !

I life saving". This conflicts with one of the appendices to the EIP which the examiner correctly quoted. This appears to be a typographic error or oversight and has been identified by the Reed Safety Committee in their audit.

SUGGESTED RESOLUTION:

Accept either 75 or 25 rem.

NRC RESOLUTION:

Comment accepted. .

I The answer key is modified to accept "75 rem", as an alternate response for part (b), accommodating the inconsistencies identified in the facility supplied reference material.

i l

I

{

l i

/ h .rFl*A l

- np-

. A ".r wrA M E* Y ANSWER KEY

{

l U.S. NUCLEAR REGULATORY COMMISSION REACTOR OPERATOR LICENSE EXAMINATION 1

Facility: REED COLLEGE i Reactor Type: TRIGA Date Administered: MAY 19, 1987 Examiner: THOMAS R. MEADOWS, RV Candidate:

INSTRUCTIONS TO CANDIDATE:

Use separate paper for the answers. Write answers on side only. Staple question sheet on top of the answer sheets. Points for each question are indicated in parentheses after the question. The passing grade requires at l least 70% in each category. Examination papers will be picked up six (6) hours after the examination starts.

% of Category % of Candidate's Category Value Total Score Value a v. z.

14.0 -lk07:_ )

A. Principles of Reactor Operation n.7 13.5 IW_- B. Features of Facility Design l

. n. z.

14.0 1+ A C. General Operation Characteristics j s f 2 ?~

15.0 W D. Instruments and Controls axr 13.25 Mr257= E. Safety and Emergency Systems .

/f.Z b 15.0 MA, F. Standard and Emergency Operating i

, ,,,,,, Procedures !

E E- IW- G. Radiation Control and Safety n.r

-100. C ^.r !

Final Grade %

All work done on this examination is my own. I have neither given nor received aid.

Candidate's Signature 4

.b

_._____________..._._____a

1

~

REQUIREMENTS FOR ADMINISTRATION OF WRITTEN EXAMINATIONS --

1. A single room shall be provided for completing the written examina-f tion. The location of this room and supporting restroom facilities '

shall be such as to prevent contact with all other facility and/or contractor personnel during the duration of the written examination. >

If necessary, the facilit a suitable room at a locak should make school, motel,arrangements for the ,use or other building. Ob-of

,q.. taining this room is the responsibility of the licensee.

E' 2.

- Miriimum determinedspacing is fre!utred by the chi to Minimum examiner. ensure examination spacing should integrity be one as l candidate per table, with a 3-ft space between tables. No wall e charts, models, and/or other training materials shall be present in

_ the examination room.

3. Suitable arrangements shall be made by the facility if the candi-dates are to have lunch, coffee, or other refreshments. These arrangements shall comply with Item 1 above. These arrangements

~

shall be reviewed by the examiner and/or proctor.

4. The facility staff shall be provided a copy of the written examination and answer key after the last candidate has completed and handed in ~

his written examination. The facility staff shall then have five working days to provide formal written comments with supporting documentation on l the examination and answer key to the chief examiner or to the regional !

. office section chief. .

5.- The licensee 'shall provide pads of 8-1/2 by 'll in. lined paper in

unopened packages for each candidate's use in completing the exam-ination. The examiner shall distribute these pads to the candidates.

. All reference material needed to complete the examination shall be furnished by the examiner. Candidates can bring pens I calculators, or slide rules into the examination room,,and pencils, no other equipment or reference material shall be allowed.

6. Only black ink or dark penctis should be used for writing answers to questions. ~

Examiner Standards

.e, . .

NRC RULES AND GUIDELINES FOR LICENSE E)(AMINATIONS During the administration of this' examination the following rules apply:

e .

1. Cheating on the . examination means an automatic denial of your application' and could result in more severe penalties. .

i

,;' . 2. 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.

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

[fB. 4. Print your name in the blank provided on the cover sheet of the yR. s. examination. , .

[, 5. Fill in the date on the cover sheet of the examination Of necessary).

h 6. Use only the paper provided for answers.

t-F 7. Print your name in the upper right-hand corner of the first page of each

!, section of the answer sheet.

[ 8. Consecutively number each answer sheet, write "End of Category " as .

appropriate, the paper, andstart writeeach "Lastcategory' Page on the last answer sheet.on a new page, write

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

1

10. Skip at least three Ifnes between each answer.

," 11. Separate answer sheets from pad and place finished answer sheets face

down on your desk or table. '- -

t.I I. -

. \

!. 12. Use abbreviations only if they are comonly used in facility literature.

i t

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

question and can be used as a guide for the depth of answer required.

t I

~

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

15. Partial credit may be given. Therefore, ANSWER ALL PARTS OF THE QUESTION AND DO NOT LEAVE ANY ANSWER

BLANK..

16. If parts of the examination are not clear as to intent, ask questions of the examiner only.

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 assiktance in completing the examination. This must be done after the examination has been completed. -

Examiner Standards .

L

18. When you complete your examination, you shall: ,.

a. Assemble your examination as follows:

.t

. (1) Exam questions on top. .

(2) Exam aids - figures, tables, etc. ;

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

b. Turn'in your copy of the examination and all pages used to answer the examination questions. ,

c. Turn in all scrap paper and the balance of the paper that you did

j. . .,. . not use for answering the questions.

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.

. . l

)

1 i Examiner Standards .

\

l l

l 1

l EQUATION SHEET f = ma v = s/t w = ag 2 Cycle efficiency =

s = v,t + at er (

E = mC a = (vg - v,)/t ,gg KE = mv vg A = AN

= v, + a t A = A,e PE = agh m = 0/t A = in 2/t g a 0.693/t g W = vaP AE = 931Am g , (t q)(t w)

(t +t) 3 Q = [nCpAT I = I e'i*

Q = UAAT I=Ie-U*

Pvr = Wg$ ~

I = I, 10

P = P, 10 SUR(t) TVL = 1.3/u P=P O et/T '

HVL = O.693/p SUR = 26.06/T T = 1.44 DT SCR = S/(1 - K,gg) eff SUR = 26 CR x = S/(1 - K,ggx)

T = (1,/p ) + [(6 - p)/A,ggo ] CR y (1 - K,gg)3 = CR y (1 -1 ,ff)2 7 ,g*j g , g M = 1/(1 - K,gg) = CR g/CR0 I"I ~ P) A eff P M = (1 - K,gg)0 ( ~

eff}1 8"I eff -I)! eff " A I eff eff SDM = (1 - K,gg)/K,gg p= ~

g* = 1 x 10 seconds

[L*/TK,ff-) + [5/(1 + 1,ggT )) ,

P = I4V/(3 x 1010) A,gg = 0.1 seconds

-I E = Na 1d33=1d22 WATER PARAMETERS Id g =Id22

,1 gal. = 8.345 lbm l R/hr = (0.5 CE)/d (meters)

I gal. = 3.78 liters R/hr = 6 CE/d (feet)

I ft = 7.48 gal.

MISCELLANEOUS CONVERSIONS . I Density = 62.4 lbm/ft 3 1 Curie = 3.7 x 1010dps Density = 1 gm/cm 3 1 kg = 2.21 lba Heat of vaporization = 970 reu/lbm I hp = 2.54 x 103 BTU /hr Heat of fusien = 144 Bru/lbm 1 Mw = 3.41 x 10 Btu /hr 6

1 Atm = 14.7 psi = 29.9 in. 18 I Btu = 778 ft-lbf 1 ft. H yo = 0.4333 lbf/in2 1 inch = 2.54 cm T = 9/5 C + 32 "C = 5/9 ( F - 32)

I l

l CATEGORY A l Principles of Reactor Operation

DUESTION ._

A.1 (1.25)

A reactor is at a very low power level , and increasing in power with a Reactor Period of 25 seconds.

How much time would be required for the power level to increase by a factor of 1000 (3 decades) ?

1 4 ANSWER A.1 (1.25) i b

I' T = 25 sec.

t /T t/25 P/Po = 1000 = e = e (O.75) !

In 1000 = t/25 1 l

t = 25 In 1000 k e- 172 secondt (2.87 min.)

t (0.5) or SUR = 26.06/25 = 1.04 dpm (0.75) l 1

time f or 3 decades = 3/1.04 = 2.88 min. (0.5) i 4 REFERENCE Reactor Phyc2cc. Module 5 l 5tephenson, R. McGraw-Hill i Equation cheet i

i A-1 l i

OUESTION A.2 (1.5) ,

A reactor is subtritical with a Keff of 0.95. Due to the addition of a reactor experiment, the indicated count rate has increased 1

from 10 cps to 20 cps. l What is the new Keff of the reactor ?

1 44NSWER I 1

A.2 (1.5) 1

! {

1 new Keff: l l

[

! CR1/CR2 = (1 - Keif 2) / (1 - Ke44 1) (0.75) ]

10 / 20 = (1 - Keff 2) / (1 - 0.95) (0.5)

(0,5) > (0.05) = <1 -

Keff 2)

Keff 2= 1 - (0.51(0.05) = 0.975 (0.25) l I

4 REFERE14CE k

Reactor Ph y si c s , (1odul es 4 and 5 Equation sheet l

l A-2

l i

l

DUESTION j A.3 (2.25)

The MARK 1 reactor is operating at 250 tw (full power) and the reactor power level trip is incorrectly set for 125% full power.

A reacitivity ex cur si on creates an approximate stable reactor l period of 200 mil 12 seconds. The reactor trips with a control element (scram del ay) time of 0.5 seconds. (assume no temperature or void effects; and that poveer peaks and turns after a complete rod drop)

a. At what power level will the reactor trip with this incorrect trip setting ? (0.25)

b. What peak power will be reached ? (1.5) (

l

c. What is the maximum control element drop delay time !

allowed by Technical Specifications ? (0.25) I

d. At what percent full power should the power level (0.25) trip be set ?

ANSWER A.3 ( '. 25 )

a. 250 kw '

1.25 = 312.5 Pw (0.25) l 1

)

b. T = 200 - 10(-3) sec = 0.2 see PCfinal) = P (i ni t i al ) -

e (t /T) (0.5)

P(final) = 312.5 kw - e(.5/.2) (0.5)

P (f i nal ) = 312.5 Ir w x e (2.5)

= 312.5 kw " 12.18 l

P (f i nal ) = 3E;O7 kW (O. 5) l l

l l

c. ( less than ) 1 second (0.25)

d. 110 % (275 I wi (0.25)

{

PREFERENCES EDUATION SitEE1 Reed TECHNICAL SPECIFICATION A-3

l

DUESTION A.4 (1.5)

Following a scram there is an initial prompt drop in power level )

fol1 owed by a power decrease and a negative period.

a. What is the magnitude (value) of this negative (0.5) l l period ? j

b. Why is it always the same ? (1.0) l l

tANSWER A.4 (3.D)

a. ~80 seconds.

b. Power cannot decrease faster than mean life time of longest lived precursor. (This is 1.44 >: 55 sec 1/2 life of Br) 4PEFEREl4CE Reactor Physics. Modules 4 and S l

i A-4 l

l

.*OUESTION A.5 (2.5)

Refer to FIGURE A.5 which shows as instantaneous, negative, reactivity insertion into an already critical reactor (at t = O_), j followed by a removal of this negative reactivity after a stable j reactor period is reached (at time t = 1), thus making the i reactor just critical again. Assuming no source neutrons: )

l (a) Show the resulting REACTOR PERIOD as a (1.0) function of time for these reactivity changes.

(b) Show the resulting REACTOR POWER RESPONSE as (1.0) a function of time for these reactivity changes.

(c) What accounts for the shape of the reactor (0.5) power response or reactor period response ;

during the time IMMEDIATELY AFTER t = 0 ? l l

I

ANSWER l A.5 (2.5) j i

(a) AND (b) ATTACHED (c) " Prompt Drop" or "Trainsent Period" due to the decrease in prompt neutron production with the decreased reactivity.

REFERENCE

,' Reactor Physics, Modules 4 and 5 1

A"5

_ FG WM ^*5

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t.0 opny t=t i i

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,=

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y l i i g 1 y ' , _._ _ _ _ z_ r]_ _ _ _ _ _ _ _ _ _ J Co.

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ssas pTo=*

kdgp' , ,'NY y ,

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( _

t,* O tst

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1

- i i

I J

ANSWER I A.6 (2.5) l l

Figure A.6 is a sketch of Reactor Power vs Time in hours, j At t = 0 hours0 days 0 hours 0 weeks 0 months a reactor startup from Xenon free conditions to l

100 % power occurs.

At t = 70 hours8.101852e-4 days 0.0194 hours 1.157407e-4 weeks 2.6635e-5 months a reactor trip occurs followed by a reactor startup to 100 % power at t = BO hours.

l (a) Sketch the Xenon reactivity response in the (1.0) core f rom this power transient.

(b) At what time will Xenon first reach (0.5) appr ox i matel y equlibrium concentrations for 100 % power ?

(c) At what time will the maximum rate of rod (0.5) )

motion be required in order to overcome the Xenon transient 7 ( Assume reactivity f rom rods and Xenon only)

(d) Will this rod motion be IN or OUT ? (0.5) 2 ANSWER A.6 (2.5)

I (a) See the ATTACHED i.ey (b) 40 to 50 hours5.787037e-4 days 0.0139 hours 8.267196e-5 weeks 1.9025e-5 months 1 (c) 80 to 85 hours9.837963e-4 days 0.0236 hours 1.405423e-4 weeks 3.23425e-5 months (e) IN tREFERENCE Reactor Physics, Modul e 12-7, pages 14 - 27 A-6 a_________________________ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _

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' I ec0ictsRidA1 Edda uBRd)M (o.y ) ii (o,f)i I oM5MTb d ( [PassistF 96 9 l(c; 4)l l l

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I. 67Ico% b I I E0*u E,Clidh ..

I l W. tw HR I !

i I I I i ,

I l 1 w . ,

F4Z4 , l t,o 6W tsto s. em e s ,,o i MS N15 M% g gs l Figure A,6 KEY sgr .

G 9

l i

i 1 k l *DUESTION f l A.7 (1.0) i Why are burnable pos sons added to TRIGA reactor cores upon initial core loading ? l 4 AtJ5WER A.7 (1.0)

So ttiat niore 4 uel can be loeded ini t i all y (without additional control rod worth) i dREFERENCE Reactor Physicr tiodul e 12. peger:, 23-24 F e atur e ra of Faci 12ty Dc+si gn 1 1

1 1 1

l I

A-7

DUESTION A.B (1.5)

What are the three(3) materials that serve as moderators for the

_ MARK I TRIGA reactor? ( O.5 pts. each) l l 4 At1SWER l A.8 ( 1. 5., 0.D pts. each)

(1) water (2) graphite (3) zirconium hydride

Reference Reed Reactor Physics Traini ng Modul e, Features of Reactor Design 1

i I

A-8

i i

. 1 CATEGORY B Features of Facility Design ;

QUESTION ~~

l B.1 ( 2.5 ) i i l l i l Figure B.1 ( attached ) is a cutaway view of a TRIGA Mark I j reactor: i l

l What are the components identified by the following letter indicators on Figure B.1 ?(name each component below) l \

Name of component: ( O.5 pts. each ) 1 A _ _ _ _

B ____

C _______

D _______

E _ _ _ _ _

4 ANSWER l B.1 ( 2. 5, 0.5 pts each, al so see Figure B.1 - KEY )

A: Isotope removal tube B: Rotary specimen rack C: Ion chamber (s) ( detector )

D: Ref l ect or E: Control Rod )

REFERENCE Reed Mechanical Maintenance and Operating Manual, page 4 B-1

CDN1R01 ROD DRIV [

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QUESTION B.2 (1.0)

Where i,s the maximum neutron flux posi t i on in the Reed TRIGA l core?

4 ANSWER B.2 $.1. 0 )

(1he dry thi mbl e at) the center of the core .

4 REFERENCE G.A. Triga Mark 1 Reactor Mechanical (1aintenance and Opereting (1anual Reed SAR, page 5-7 I

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DUESTION B.3 (2.5)

A reflector is provided in the design of the TRIGA reactor to allow a reasonably sized core.

l (a) What material is used to provide radi al neutron reflection ? (0.5)

(b) How is water kept from coming into contact with this reflector mat eri al when the reactor tank is flooded ? (1.0)

(c) How is the weight of this reflector assembly supported by the reactor tank? (1.0)

ANSWER B . 'J, (2.5)

(a) graphite (0.5)

(b) The reflector is encased by a wel ded (aluminum) container. (1.O) 1 (c) The reflector assembly i s wel ded to the reflector platform. The platform rests on four 1egs which are bolted to the bottom of the (aluminum) reactor tank. (1.0) l 4 REFERENCE G.A. Triga Merk I Reactor Mechanical Maintenance and Operating Manual, Section 3 l

l l

l b-3

l

OUESTION B.4 ( 2.0 )

Figure B.2 (attached) is a drawing of a typical fuel element used

~

in Reed's core: .

I (a) What is the name of the component labled A on '

Figure B.2? (0.5)

(b) Of what material is the the component labled A on Figure B.2 made ? (0.5)

(c) What is the name of the component labled B on Figure B.2? (0.5) 3 i

(d) Of what material the the component labled B on I Figure B.2 made ? (0.5) 1 I

ANSWER B.4 (2.0) see Figure - D.2 enswer key (O. Sot. for component name)

(0.5pt. for what component made of) i 1

PEFERENCE G.A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual, Reed SAR, page 5-12 l

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QUESTION B.5 (1.5)

Refer to Figure B.2 (attached), a drawing of a fuel element.

(a) Of what material is the component labled "C" on Figure B.2 made? (0.5)

(b) What is the purpose of the material labled "C" on Figure B.2 ? (1.0)

ANSWER B.5 (1.5)

(a) graphite (0.5)

(b) To provide vertical (axial) neutron reflection for the reactor core. (1.0) 4 REFERENCE G.A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual.

Reed SAR, page 5-12 l

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

OUESTION B.6 (2.5)

The Rotary Specimen Rack is one of the in-core design features of a TRIGA reactor that is part of the irradiation facility.

(a) Of what material is the rotary specimen rack made? (0.5)

(b) How is the accumulated condensation absorbed in the rotary specimen rack ? (1.0)

(c) How is water leakage detected in the rotary specimen rack ? (1.0)

ANSWER B.6 (2.5)

(a) Aluminum (0,5)

(b) Each of the f our (4) perforated specimen tubes can be loaded with (a porous contai ner 4illed with) a water absorbing agent. (1.0) 1 (c) One of the perforated specimen tubes has a small ( O.625 inch ) sampling hole drilled its bottom to allow water to j enter the tube from the chamber for detection. (1.0)

REFERENCE i G.A. Triga Mari: 1 Reactor Mechanical Maintenance and Operating Manual. section 4 B-6

e

DUESTION B.7 (1.5)

There are two(2) conductivity probes in the water system. Probe !

I "A" is located upstream of the demineralized, in the process line l eadi rig f rom the reactor t a n k.. Probe "B" is located downstream of the demineralized.

(a) What is the reason for Probe "A" sampling the water conductivity in its location? (0.75) l (b) What is the reason for Probe "B" sampling the water conductivity in its location? (0.75) 4 ANSWER B.7 (1.5)

(a) High conducti vi t y in the procesc flow leading from the reactor t anl: is en indication of a fuel el ement failure

[elso: an integrity f ailure of an in-core experiment (0.25),

or failure of the water cooling system heat exchanger (O.25)-( O.75 pts. mar 1 MUM )3 (0.75)

(b) High conductivity in the process f1ow leading from the demineraliter is an indication of depl eted recin (and/or improper d emi ner al i t er operation such that the resin 4ai1c). (0.75)

REFERENCE G.A. Triga Mark I Reettor Mechanical Maintenance and Opereting Manual, section 5 4444444444(444r44444444t44444***14444444*tt$4414444*444***44444**

END OF CATEGORY B B-7

OUESTION B.7 (1.5)

There are two(2) conductivity probes in the water system. Probe "A" is located upstream of the demineralized, in the process line leading from the reactor tank. Probe "B" is located downstream of ~

the demineralized.

(a) What is the reason for Probe "A" sampling the water conductivity in its location? (0.75)

(b) What is the reason for Probe "B" sampling the water conductivity in its location? (0.75) 4 ANSWER B.7 (1.5)

(a) High conducti vi ty in the proceen flow leading from the reactor t an i: is en indication of a fuel el ement failure telso: an integrity f ailure of an in-core experiment (0.25),

or failure of the water cooling nystem heat exchanger (0.25)-( O.75 pts. MAXIMUM )3 (0.75)

(b) High conductivity in the process flow l eadi ng from the demi ner al i z er is an indication of depleted recin ( an ct / or improper demi neral i z er operation such that the resin failt). (0.75) 4 REFERENCE G.A. Trige Mari; I Reactor Mechanical Maintenance and Opereting Manual. section 5 1

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CATEGORY C General Operating Characteristics

DUESTION I

_ C.1 (2.75)

The Reed TRIGA reactor has been designed with a large prompt negative fuel temperature coefficient (FTC). Three principle ef f ects provide this negative FTC; doppler, core leakage, and cell inhomogeneities. l (a) How does DOPPLER produce a negative Fuel Temperature Coefficient? (0.5)

(b) How does CORE LEAKAGE produce a negative Fuel Temperature Coefficient? (1.0) l (b) How does CELL and INHOMOGENEITIES (Zr-H fuel / moderator) l produce a negative Fuel Temperature Coefficient? (1.25) l l

AllSWER C.1 (2.75) j (a) With increasing fuel temperatures the resonance absorption bands (of U-238 and Pu-240) broaden, which increases the probebi1ity of a non-fiseion capture of an epithermal neutron within the fuel. (0.5)

(b) Wi th increasing fuel and Zirconium Hydride temperature )

the thermal neutron population is hardened (increased energy ) (0.5), thereby increasing the average distance a thermal neutron diffuses. This increased thermal neutron i I

mi gr at i on length results in an increase in core leakage. (0.5) (1.0) ]

(c) Wi th increasing fuel and Zirconium Hydride temperature i the thermal neutron population is hardened (increased ener gy ) (0.5). thereby decreasing the probability of i

absorption and f i ssi on in U-235 (0.5). This, along with '

the non-homogeneous core construction increases the probability of thermal i z ati on and absorbtion in the surrounding water (0.25). (1.25) l l

l 4 REFERENCE Reactor Physics, Module 12-6,page 6-19 Stephenson, R. McGraw-Hill C-1

ANSWER C.2 (1.0)

Of the three(3) contributors to the negative fuel temperature coefficient (FTC); CELL and INHOMOGENEITIES, DDPPLER, and CORE LEAKAGE:

Which one(1) i s the dominant or principle effect ?

4 ANSWER C. 2 (1.0)

CELL and 1 NHOt10 GENE 17 I ES

REFERENCE Reactor Physics, t1od ul e 12-6,page 6-19 Stephenson, R. ficGraw-Hill C-2

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1

OUESTION C.3 (2.5)

The REED reactor pool (or pit) provides water for cooling the fuel elements.

(a) What is the path of cooling water flow f rom the area of the fuel elements to the area above the upper grid plate? (1.0)

(b) What is the motive force for this cooling water flow? (0.75)

(c) What is the cooling water flow path from the pool to the fuel element area? (0.75) l

ANSWER

! C.3 (2.5)

(a) Cooling water pesses through the gap between the triangular spacer block at the top of each fuel ,

element and the circuler hole in the upper grid plate. (1.0)

(b) Natural Convention (0.75)

(c) Cooling water flows through (31) special holes provided in the lower grid plete. (0.75) 4 REFERENCE G.A. Triga Mark 1 Reactor Mechanical Maintenance and Operatang Manual, Section 3 C-3 l.

i

DUESTION j C.4 (2.25)

What are the approximate reactivity worths of each of the f ollowing control rods?

(0.75 pts. each)

(1) shim (2) safety (3) regulating l l

l

ANSWER I l C.4 (2.25, 0.75 pte e'a c h ) )

/

(1) shim, 2. 8% del ta K/K

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t Ink f%2.f 7 (2) safety, 2.8% delta K/L,.

/ ff0 Au CW $ (2 ) J~s rc 77> ft/;ff" r,,, g,,,j (3 ) secs.s4srin};, p (3) reculatino.

1.0 del te K/K

_ _ w 4 REFERENCE Reed SAR, pages 5-8 through 5-10 <

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("A C ' 4 1 7 }" F V /.acEg*C 74~f7 s k rc<W 7/ 5/V (A f 7/*A gu,ym, _,p l

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QUESTION C.5 (2.0)

The design of the MARK 1 reactor incorporates a water pool (or pit).

l l

(a) At what bulk pool temperature must the reactor be l shutdown in accordance with Reed's Technical Specifications (0.5)

(b) What is the minimum pool level, as specified in the Reed Technical Specifications, for the operating reactor? (0.5) l (c) What are two(2) reasons for this minimum level? l

( O.5 point each ) (1.0) l i

4 ANSWER I C.5 (2.0)

I i

(a) 120 d agsr ees F (0.5) j i

(b) 16 feet above the top of the grid plate (0,5)

(c) (1) Lhiel di ng f rom the core ( 0. 5) l (2) allow pool cksmmer to operate (0.5)

[ww ssro s e < . v ? Q ) s-o n o. f pos& 77,. wowg w g, F#47 6" ) ms t ,.ec.-r ,e a k /. p poO rs ,1,y,,,,,,, f 4 REFERENCE J Reed Technical Specifications, pages 2-4; G.A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual, pages 26a and 81 0b a ff fp / 'k J' VML~ , FM dP[ A .psjp , p p ;- , , , , , g p4 f f!" T/'C C o u r n pi. se p sj sj , ,g,g g , , *

(0-f C-5

OUESTION l C.6 (1.0)

In accordance with with Reed's Technical Specifications, all fuel elements or f ueled devices shall be stored _

such that criticality will not occur in the reactor pool. In accordance with with Reed's Technical Specifications.

(a) How many fuel elements can EACH of the fuel storage racks hold ? (0.5)

(b) What i s the maximum Kef f allowed in the fuel :

l racks under all conditions of moderation 7 (0.5) l 4 ANSWER C.6 (1.0)

( #. ) 10 (0.5) ;

i (b) Keff Iess than O.8 (O.5)

REFERENCE Reed Technical Specif2 cations, pages 2-4 )

I t

C-6

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OUESTION l C.7 (1.0) l l

4 SELECT THE BEST ANSWER !

~If, while operating the reactor at 100% power, a nitrogen supply line to an in-core experiment ruptured causing a large nitrogen bubble to f orm in the core region ( 75% core volume ), the core's reactivity would; (a) remai n unchanged as nitrogen does not act as a significant neutron absorber or producer.

(b) become prompt critical as the nitrogen would displace the moderator without affecting prompt neutron production.

1 (c) become subtritical as the nitrogen would provide a large negative void coefficient.

(d) become source critical due to the large production of N-16 gammas.

AHSWER C.7 (1.0) .

I (c) tREFERENCE G.A. Triga Mar k I Reactor Mechanical liai nt enance and Operati ng Manual, Reed Nuclear Technol ogy F'hysi cs Modul es l

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OUESTION C.8 (1.5)

Reed's Emergency Implementation' Procedures identify NORMAL PARAMETERS (READINGS) for seven(7) environmental monitors during l reactor operations. Four(4) of these are: l (1) Caseous Stack Monitor at 100 cpm (2) Particulate Stack Monitor at 150 cpm (3) Portable Survey Meter (GM) at reactor room door at 0.1 mR/hr.

(4) Bulk Pool Water Temperature at 15 degrees C.

l l

l What are the NORMAL PARAMETERS (READINGS) for the other three(3)' environmental monitors given below ? (0.5 pts.each)

(a) CAM (b) RAM (c) Secondary Water Pressure

ANSWER C.8 (1.5, 0.5 pts. esch)

(e) 400 cpm (f p - y 0 4 v'M, ^ cc l~n 'A dd t~)

(b) 0.1 mR/hr( p p y ,n,,,. _ p , , , , ,,,, ,., gg g.)

- (C) bb D*A ( 4*d 9 G sr/ , A m mpy) i

$ REFERENCE i Reed Emergency Implementation Procedures, APPENDIX D I i

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END OF CATEGORY C ,

C-9

CATEGORY D Instruments and Controls

OUESTION D.1 (2.5)

Figure D.1 is a drawing control rod drive mechanism.

Match each component listed below with it's location on the control rod drive mechanism as defined by the letter on the attached drawing.

1 (0.5 points each)

(a) Push rod j (b) Pull rod (c) armature (d) potentiometer (e) motor

ANSWER l D.1 (2.5)

(a) D (b) A (c) G (d) C (e) B l

l

REFERENCE Reed SAR, page 5-10 l

D-1

MAGNET WIRE CONOUlT MAGNET DOWN A0JUSTMENT SCREW MOTOR BI AS ADJUSTMENT MAGNET ORAW TUBE '

CENTER SWITCH MOUNTING PLATE ROD DOWN LIMIT SWITCH

- 8 MAGNET WIRE CONDUAT PULL-ROD EPRING l -MAGNET UP LIMIT SWITCH

< ~ L i ADJUSTMENT SCREW

A b g" , ,. , f s

C .

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Fig. P-l -Rod drive mechanism, showing components and adjustment locations l l

1

DUESTION D.2 (2.0) l REFER to figure D-1, a drawing of a control rod drive mechanism.

(a) What i s the f uction or purpose of the pull rod ? (0.5)

(b) What is the f uction or purpose of the push rod ? (0.5) l (c) What is the purpose of the potentiometer ? (0.5)

(d) What action occurs in this mechanism to allow a rod to drop on a reactor trip or scram? (0.5) ;

I 4 ANSWER l D.2 (2.0)

(a) p rovi den a rod bottom indication (rod attached to rod down j switch). !

1 (b) provides a rod full withdrawn indication (rod attached to full up switch).

(c) provides rod position indication when the electromagnet engages the iron armature.

l (d) the el ectromagnet de-energizes and releeces the iron ]

armature allowing the rod to drop.

4 REFERENCE Reed 5AR, page 5-10 I

D-2

i

QUESTION D.3 (1.5)

A Neutron Source i s provided in the design of the Reed reactor.

(a) Why is a neutron source important for reactor operation _

after a long shut down period 7 (1.0)

(b) What type of source i s provided ? (0.5) tANSWER D.3 (1.5)

(a) To ensure that nuclear powcr can be accurately monitored during a reactor startup from low i ni t i al count rates.

(b) polonium - bery11ium (wa a. s s rcr A u g./>? A# OC ^/

, (plutonium) ^"s*"AMCremet?)

l l 4 REFERENCE l

l Technical Speci f i c ati one; l Reactor Physics, riod ul e 12-1, pages 7-8:

1 Reed SAR. page 5-5 l

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D-3

l

DUESTION D.4 (1.5)

Holes in the central thimble tube ensure that it is normally 4 filled with water. However, a speci al cap may be installed on

the top end, sealing the tube. Compressed air is then applied, i which subsequently removes the water column to accommodate l

certain experiments.

(a) Why would the water column be removed from the central thimble tube 7 (0.5)

(b) How would the flooding of an air filled central thimble tube initially affect reactor power if critical in the power range 7 (1.0)

ANSWER D.4 (1.0)

(a) To creatr-- a well - collimated beam of neutrons (b) Power will increase l

i 4PEFEREtJCE Reed EAR. pages 5-7 D-4

ROUESTION D.5 (1.5)

Reactor power is monitored by neutron detectors installed near the core in the Reed reactor. _

(a) What type of detector is used f or the count rate l

channel ? (0.5)

(b) What is the range of the count rate channel in terms j of percent reactor power? (0.5)

(c) What reactor protection features are provided by the count rate channel ? (0.5) 4 ANSWER D.5 (1.5)

(a) f i sei on counter (b) 5> 10^(-4)% to 10"(-2)%

( 1 cps to 10^5 cps )

(c) The bistable prevents control rod withdrawal bel ow 2 cps.

REFERENCE G.A. TRIGA MARiL 1 Reactor Mechanical Me2ntenance and Operating Manual, page 1-7, and page 1-13 of Appendix E4

)

i D-5

l

]

20UESTION l D.6 (1.0) j In the steady-state mode the linear power channel provides power indication f rom below source level to full power. This is accomp1ished with a fourteen (14) position range switch.

4 (a) What type of detector is used in the LINEAR POWER CHANNEL (0.5)

(b) What reactor scram or trip f unctions are provided by the LINEAR POWER CHANNEL (0.5) 1 1

2 ANSWER D.6 (1.0)

(a) compensated ion chamber (b) Reactor scram (trip) at 110% full scale for each range

~

4 REFEREtJCE G.A. TRIGA MARK 1 Reactor Mechanica) Mai titenance and Opereting Manual. Appendi: B. page 13 l

D-6 1

1

)

k i

DUESTION i D.7 (2.0)

An automatic reactor control system i s provided f or steady state !

l operation. During automatic operation the comparator circuit in the servo amplifier obtains three(3) inputs in order to regulate reactor power. One(l) of these three(3) inputs is power demand from the power demand potentiometer.

(a) What are the two(2) other inputs to the comparator circuit? (0.5 pts. each) (1.0)

(b) Which nuclear instrumentation channel supplies each of the two(2) additional inputs?(0.5 pts. each) (1.0) 4 ANSWER D.7 (2.0)

(a) (1) reactor power (O. 5)

(2) reacter period (0,5)

(b) t1) power: 1incar power channel (O. 5)

(2) period: the per2od circuit of the log power channel (O. D) 4 REFERENCE G.A. TRIGA MARK 1 Reactor Methenical Maintenance and Operating Manual j D-7

l j

i 2 QUESTION D.B (1.5)

The FISSION CHAMBER is a type of neutron detector at Reed.

(a) SNetch or describe the detector construction or geometry? (0.5)

(b) What materials are used to allow detection of neutrons? (0.5)

(c) What region of the output pulse verses detector j voltage curve does the FISSION CHAMBER use ? (0.5) l

ANSWER D.O (1.5)

(a) Concentric con (cathode) end central probe (anode)

(b) U-235 (c) proportional

REFE FiE NCE Detector Fundamentals 4

D-B

1 l

QUESTION D.9 (1.5)

The Compensated Ion Chamber is anouther type of detector used at Reed.

(a) Sketch or describe the detector construction or I geometry? (0.5)

(b) What materials are used to allow detection of neutrons? (0,5) i i

(c) What does the COMPENSATED ION CHAMBER compensata for 7 (0.5) l 4 ANSWER j D.9 (1.5)

(a) Two dif 4 erenti al1y connected det et t i nci v o ] u m e r. , on1y one l

of which is coated W1th a neutron sensitive materiel.

l l (b) boron l

(c) camma r acti e t i on 4 REFERENCE Detector Fundamental l

l l

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D-9

CATEGORY E Safety and Emergency Systems 1

OUESTION

~ E.1 (2.25)

Reed's Technical Specifications identif y three(3) specific conditions, associated with the reactor control systems, for placing the reactor in a shutdown condition.

l What are the three(3) conditions that must be met before the reactor is considered shutdown? ( O.75 each ) (2.25)

ANSWER E.1 (2.25, 0.75 ptt. each) l l

(1) The consoir ley switch is in the DFF poci t i on and the i.ey is i removed f rom the console, under the control of a licensed I operator ( or stored in a locked storage area).

(2) Sufficient control rods are inserted to assure the reactor i is subtritical by a margin greater than O.7'/. delta KA: (i n a cold. Xenon free condition).

(3) No wor t- is in progress involving fuel handling, ref ueling, or maintenance of control mechenisms.

tREFERENCE l'IARK 1 Techn1cel Sp ec i f i c at i on e. , Definitions t

l l

E-1 l

DUESTION E.2 (1.0)

In accordance with Reed's Operating Procedure, SOP-04, going up in power: _

With the e>:ception of the Safety rod, no rod should t;e removed greater than 95% of its full length.

What is the reason for this precaution ?

ANSb!ER i E.. (1.0) J l

To assure edequate dif4erintial rod wor t t i to that incremental rod )

insertion provides adequate negati ve reacti vi ty insertion. {

( rodt have adequate bite )

4 REFERENCE Reed Ecp-03, Godng Up In Power 1

l l

I l

l E-2

i a

I I

QUESTION E.3 (2.0)

According to Reed's Emergency Implementation Procedures, the Reed f acility has in place f our (4) radiation monitors to detect a fuel element failure in the reactor core or storage pool, and initiate the evacuation alarms and/or ventilation j confinement system.

(a) What is the alarm setpoint f or the CAM ? (0,5)

(b) What is the alarm setpoint for the RAM ? (0.5)

(c) What are the two(2) other radiation monitors that are provided to detect a fuel element failure and initiate I

the evacuation alarms and/or ventilation confinement system. (0.5 pts. each) (1.0)

I 4 ANSWER E.3 (2.00)

(a) 2000 cpm (O.S)

(b) 2 mR/hr (0,5)

(c) (1) Gareouc 5tacL Monitor (O.D)

(2) Particulate Stack Monitor (0,5)

(

4REFEREMEE Reed Emergency I mp l ement at i on Procedures, page 2 and Append 2r D 1

i 1

1 l

1 E-3 l

1 l

QUESTION E.4 (1.0)

The operating license and Technical Specifications for Reed define the designed steady-state operational power level of the reactor- 1 l

l l (a) What is the maximum steady-state operational power level specified by the Reed Facility operating license? (0.5)

(b) What is the maximum steady-state power level for the purpose of testing the 110% full power safety circuits. (0.5) 4AN5WER j E.4 (1.0) J l

ta) 250 6.: W (utilizing Table 1 e:n d 11 s c r arns and i n t er l oc l:s ) (0.5)

(b) 287. 5 i:W [/ ' ' ' ' " c r, 270av) (0.5)

REFERENCE Reed Technical Specification, Defanitione, A' cr t' e sc'< s r s " c- L s izw r z.-

i l

I l

E-4

l 1

i

QUESTION 1 E.5 ( 2.0) f l

In the event of accidental air contamination:

{

)

(a) What happens to the air system supply unit A in the reactor !

room? (1.0) j 1

(b) 1 What is the reactor room air flow path after realignment of )

the automatic dampers? (1.0) 1 l l J

ANSWER q

E.5 (2.0) j i

(a) shuts down (b) Reactor room air zu directed through abcolute filters, mixed with outside air, and directed up the stack. l

REFERENCE Reed SAR, pages 4-5 through 4-7 1

l l

E-5

9

OUESTION )

E.6 (2.0)

After an accidental air contamination:

(a) What happens to the air system supply unit C in the i control room? (1.0)

(b) What is the control and maintenance room air flow path after the realignment of the automatic dampers (1.0) 4 ANSWER E.6 (2.0)

(a) remains operating (b) All ai r in reci rcul at ed within the control aa n d mai nt ersenc e room.

4 REFERENCE l

Reed SAR, pagee 4-5 through 4-7 l

l l

1

! l l l l

E-6

4 i

1

DUESTION j E.7 (1.0)

How often must control elements be ianspected f or distortion or ,

deterioration ?

4 ANSWER ;

E.7 (1.0) every two years tREFERENCE j Reed Technical Specifications l

l E--7

1 l

I 1

DUESTION E.8 (2.0)

How often must the f ollowing saf ety system tests be perf ormed ?

{

(a) control element drop times (1.0) f (b) f uncti onal test of the ventilation system interlocks (1.0) 4 ANSWER E.8 (2.0)

(a) semi - annual l y (except if the reactor it opersiting continuously )

(b) semi - annual l y (except if the reattor is operati ng continuously )

4 REFERENCE Reed Technical Speci f 2 cstti onn I i

l l

444444444444444444444444444444444*444*4$4144444444**4444444444444 END OF CATEGORY E E-8

CATEGDRY F Standard and Emergency Operating Procedures

QUESTION F.1 (2.O)

The G.A. TRIGA Mark I Reactor Mechanical Maintenance and Operating Manual cautions that when working on the Irradiation Facility (Lary Susan), if any pin fails in any coupling in the drive system (manual drive handle, upper shaft coupling, and sprocket pinion), DO NOT rep 1 ace it with a stronger pin ".

(a) What is the reason for this caution ? (1.0)

(b) What action should the operator take if a drive system coupling pin does break ? (1.0) 4ANSWEP F.1 (2.0)

(a) These p .w cre designed to be progressively stonger to that af failure occurs, it will probably be in an eccessible area. (1.0)

(b) Determine What caused the pin to fail, and reduce t he tor que (and/or friction) on the assemblv to correct the problem. (1.0) 4PEFERENCE G.A. TRIGA Mark 1 Reactor Mechanical Maintenance and Operating l Manual. page "I l l

l l

p_3

i i

l l

QUESTION F.2 (0.5)

Reed sop-51, Performing Rabbit Irradiations, states in part that "If the ion chamber reads a significant dose while the rabbit is j still i n the termi nal , . . . the rabbit should not be removed from I the terminal. l 1

l What is considered a "significant dose" with the rabbit still in l the terminal ? (0.5)

}

l 4 fin 5WER l F.2 (0.5) {

grezter then 10 rnR / hr ( 0. 5 )

REFERENCE Reed e. op -51, Perf orming Rabbi t I rr adi ati ons, 51.7 l

l F-2

4

DUESTION F.3 (2.5)

Af ter the start-up checklist is completed Reed operating procedure, sop-03, "Startup and Core Excess Check" is being l I

followed.

, (a) As the shim rod is raised, what three indications (1.0) l l should the operator monitor ?

(b) What is the minimum period used when going critical ? (0.5) l (c) When (minimum and maximum % of full scale) should (1.0) the operator shift the range switch of the linear channel 7 1

l 2 ANSWER F.3 (2.5)

(a) (0.33 each )

Count Rate cnhannel Persod meter l Linear channel 1

(b) 15 seconds ( / v - 4 0 rccw/) (0.5)

(c) 50% minimum. 75% maximum (1.0) l l

4 REFERENCE l Reed sop-03, Stertup and Core Excess Check i l

i l

F ,T

DUESTION F.4 (2.0)

! A Power Calibration i s being conducted in accordance with sop 43.

The reactor has been operating at 150 KW for two hours. l l (a) What two parameters are needed to compute the (0.5)

I actual average reactor power ? 1 l

l (b) How are the percent power and linear chambers (1.0) adjusted to read correctly 7 ,

I (c) Why does the radiation l evel in the reactor room (0.5) become unusually high ? (especially towards the end of the run)

ANSWER i F.4 (2.0) j (a) Time and temperature (0.5)

(b) The U-bolts securing the chambers are unbolted (1.0) and the chambers are slid up or down with the reactor at the same power used for the calibration.

(c) Radiation levelt rise due to the diffuser bei ng of f ( 0. 5)

(pri mary water system not on) 4 REFERENCE Reed sop-43. Power Calibration F-4

OUESTION F.5 (2.0)

While raising power in accordance with Reed Operating Procedure, sop-04, Going Up In Power:

(a) When must the reactor be placed in the automatic (0.4) mode ?

(b) When raising the shim rod, what is the minimum (0.4) {

period that the operator use ? )

1 (c) If the regulating rod " bottoms out" in the (1.2) automatic mode, what must you do to reestablish automatic control 7 (f our actions)

ANSWER F.S (2.0)

(a) When above 90% (of 250 KW) (0.4)

)

(b) 10 seconds (/0-20 .ro'e v -e l) (O.4) i (c) Place the mode switch in steady state mode, lower (1.2) l the shim rod, move the regulating rod up, and place l the reactor back in the automatic mode.

1 4 REFERENCE '

Reed sop-04, Going Up In Power, 4.3

p. 5

_______________s

l I

OUESTION F.6 (2.0)

Reed's Administrative Procedures for reactor operations identify minimum staf fing requirements f or reactor operations. l What are these minimum staffing requirements?

4 j

ANSWER F.6 (2.0)

A SRO must be present 2n the reactor facility (0.5), and the RO must be aware of his location (0.5). Two persons must be within j the reactor building (0.5), one of which must be an NRC licensed i operator (0.5). )

l

REFERENCE Reed Admi ni strati ve Pr oc ed u r e s,, 3.1.4 f l

1 I

i; l

l F-6

l l

l 3DUESTION F.7 (2.0) 1 I

Prior to Performing Rabbit Irradiation in accordance with sop 51, !

the reactor has been operating for about an hour with the rabbit !

motor off. When the rabbit motor is turned on the gaseous stack al arm sounds.

(a) What caused the stack alarm ? (0.5)

(b) What do you need to do after the alarm clears ? (0.5) i I

(c) What actions are required if an unreasonable (1.0) {

reactivity change occurs when the rabbit is )

inserted ? )

1 I

ANSWER l F.7 (2.0) l (a) Venting Ar-41 in the rabbit system ( 0. 5 )

(b) Have someone reset the (ventilation) i sol at i on (0.5)

(c) Warn the rabbit oper at or , SCRAM the reactor, (1.0) and return the rabbit with the operator out {

of the terminal area. l i

REFERENCE Reed top-51, Performing Rabbit Irradiations. 51.6 l

l F-7

QUESTION F.8 (2.0)

The Reed Emergency Plan establishes action guidelines and staff responsibilities for emergency events at the RRF. " Non-Reactor Saf ety Related Event".

(a) Besides "Non-reactor Safety Related Event", what (1.0) are the other two (2) levels of emergency classification that are used at Reed ?

(b) Who may initiate " Emergency Action" ? (0.5)

(c) Who is the " Emergency Coordinator" ? (0.5) I

ANSWER -

F.8 (2.0)

(a) Unucual Event and alert (1.0)

(b) Any reactor operator or senior reactor operator (0.5)

(c) The SRO on duty (0.5)

REFERENCE Reed Emergency Plan, .J. 1. 2 . 4.1, and 4.2 I

1

)

l 1

l i

1 i

4***$44*te44***$$$$$$4t444***4$44t$44$4*444$4444t$44***$4t****$44 END CATEGORY F F-8

.. 1 l

l l

l 1

1 CATEGORY G 1 Radiation Control and Safety

DUESTION f f o- p ,,f rf 4 z::,,M r r G.1 (2.25) ou are conducting a survey of a contaminated area with a jut ' ,

(Model 9) survey meter (shown in Figure G-1). You not the- f follgwing readings while holding the instrument close o 'the j conta'ininated area; With the TAB" in the up position, and the " LECTOR SWITCH "

in the "X 10 hr" position, the meter reads .5".

t With the "G TAB" 1 the down position, and the " SELECTOR SWITCH" in the "X 10 R/hr" p ition, the me r reads "1.3".

I l

(a) What is the GAMMA dos r e as measured above ? (trt"t)6 'd 1

(b) What is the Bet dose rate as asured above 7 Wr5)'-'

l (c' '-?t t F :d+- n eh~ad th - " e t, rrTnn c. Tcun g m gy Mm /., m nu n y up U.a -inewument ? -

(d) w is the instrument periodically rezerced ? (Gr&)(##I) J 4

(p. Z (e) What is the function or purpose of the (

l

" RED RESET BUTTON" L TAN 5WER G.1 ( 2.25 )

(a) gamma = window closed reading . ~T *-6 5 )

/JPG W/A

gamma = 13 '

n ' " " ' ' " " . _ , ,

+ (0.25)

(b) beta =[ window open - window closedf [#cre recrv/d ( . h C #JO

(/ f * * "/A - /J o#*/h)(v.s) : pao ng beta = 1-C '-

!~ ._ iv i 7 (0.25)

, . . , i.i

(. ? A/.,A )

,, , ug;a oc- e. er r e-u

,, . +_-- . - ,

(di Return " SELECTOR SWITCH" to a_ P (0.25) and adjust "ZERO CONTROL" (0.25).

(e) L .:g. uuui% d ie utu HFET D"."' cru-tl + h r' ~"-

stWSP

+u u m. '

,uiig u n.c . .l'~ eM Wh (n_ m 70 & " " l~ 7"*r ,,,,g. .p e r re ,.e p s o -am /s ferria ,*e w:r [p, ,

tREFERENCE Cr-=~ r~r y~<* .ra n e- enujn raw . . )

Reed sop-17,18,19,22 '.r m y j*

Reed Radiation Monitors G-1

QUESTION G.2 (1.0)

How long can you remain in an area with a gamma dose rate of 3.5 R/hr without exceeding the 10 CFR 20 quarterly whole body limit?

i l

4 ANSWER l G.2 (1.0) I 1

l 1 l QUARTERLY L 1111 T = 1.25 R (0.5) j 1 1 T2me = L (1.25 R) / (3.5 R/hr) J E 60 min / hr 3 (0.25) l Time = 21.4 min. (0.25)

REFERENCE 10 CFR 20 Reed Admini strati ve Procedures. pegen 2-14 Reed sop-17 l Reed Traini ng (1anual , Chapter 2, pages 18 - 20 l

1 1

i G-2

l l

,.,,- gxx .n -> + r 74 ~R

OUESTION ~

~~__,_,. j G.3 (1.5) I l Figure G-2 shows an "EBERLINE PAC iSA" portable diation

-d e .ctor.

(a) What typeNi radi ati on does thia' instrument (0.5) l measure ? N y

[ N.

l l

s

{ (b) What type of d6tector doesthis instrument

~~

(0.5) j ut i l i z e -? ' l many " counts per second" should reg N (0.5) y on the meter if the probe is held over the "U SOURCE" ? -

s*N l 1

ANSWER i

G.3 (1.5) 1 (a) Alpha i

s. l

'. b ) S c. 3 ation detector /74 44#

c) 300 to 500 cps

'~--.

.l l

REFERENCE Reed sop-l'7.18,19,22; l Reed Radiation Monitorsj L uc < w /for<1 /7) .7,,,x ue n o w g , n, <

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fe G) c. ~- o er ec - ,

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M 9'*'<*A: rs4-f, coo f)

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S. 'Y j

_f;;%,y # -

$P # '" - - ~- ~. _

OUESTION G.4 (1.5)

Figure G-3 shows a NP-2 (SNOOPY) portable radiation monitor.

i (a) What type of radiation does this instrument (0.5) i measure 7 i (b) What type of detector does the NP-2 utilize ? (0.5)

(c) What would the instrument read ( in MREM /hr) (0.5) in a 100 R/hr Gamma field 7 f )

f

ANSWER G.4 (1.5)

(a) Neutron (f ast and thermal)

(b) BF3 proportional detector (c) cero (insensitive to gamma up to 500 R/hr) l 4 REFERENCE l Reed sop-17,18,19,22 Reed Radiation Monitors

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QUESTION G.5 (1.0)

SELECT THE BEST ANSWER A point source of GAMMA radiation measures 8 R/hr at a distance of 2 feet.

Which of the following is the best estimate of the radiation dose rate from the GAMMA source at a distance of 8 feet ?

(a) 500 R /hr (b) 2 R/hr (c) 500 mR/hr l (d) 200 mR/hr l

4 ANSWER I G.5 (1.0) l 1

1 (C) DO5E RATE i nverse] y proporti onal to distance squared distance increened by 4 DOSE RATE decreased by 16 4 REFERENCE Reed Training Manuel, Chepter 2, p a g e s; 21 - 28 G-5

I 1

i l

1

OUESTION G.6 (1.5)

The Rad.iation Area Monitor (RAM) used at Reed is capable of detecting airborne contamination caused by an accident involving an in-core experiment or fuel element failure. ;

(a) What type of radiation does the RAM (0.5) detect ? )

(b) Where is the RAM installed 7 (0.5)

(f) In accordance with the Technical Specifications, ;

when must the RAMS be in operation 7 (0,5) {

4 ANSWER G.6 (1.5) l 1

(a) Gamme l (b) In the reactor room (overhead)

(c) During reactor operations ( except for short periods of repair while portable gamma instruments with alarms are in operation near the reactor,)

4 REFERENCE Reed top-17,18,19,21.22 Reed Rediation Monitore RAM Manufacturer's Instruction Manual l

G-6 l

1 l

I

DUESTION f G.7 (2.5) l l

A survey of radiation and contaminate on levels has been made by )

Radi ati on Protection personnel. The mep (Figure G-5) on the f ollowing page has the results of this survey.

Portions of 10 CFR 20 Appendix B, Concentrations in Air and Water Above Natural Background (Figure G-6), are al so provided. 4 Based only on this survey and the requirements of 10 CFR 20; (a) What posting is required in the LABORATORY ? (0.5)

(b) What posting is required in the (0.5) l REACTOR ROOM ? l (c) What posting is required in the COUNTING ROOM? (0.5)

(d) What posting is required in the MECHANICAL (0.5)

ROOM? j i

(e) Which area (s) must be locked or access (0.5) I otherwise controlled in accordance with 10 CFR 20 ?

1 l

AN5WER j G.7 (2.5)

't1 ( CAUTION ) AIRBORNE RADIOACTIVITY AREA (b) ( CAUTION ) HIGH RADIATION AREA 1

(c) ( CAUIION ) RADIA1 ION AREA (d) ( CAUTION ) RADIATION AREA (e) REACTOR ROOM REFERENCE Reed SAR. Figure 4-2 10 CFR 20 G-7

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J Nuclear Regulatory Commission Port 20, App. B APPENDIX B--CONCENTRATIONS IN AIR AND WATER AeovE '-NATURAL BACKG (See tootnotes et end of Appends 81 lootopoe Telps 1 Ta4We 11 Elemeal (stome smamtm) g,g, ,,,g Col. 2- g94 -Col.t-(uWml) *Eg (pWml) h*

toene (53) i125 8 5 x 10-* 4 x10*e 4x10"" t x 10-'

1126 l

R x 10** 8x10 8x10-' 2 x 10-*

8 8 x10-8 8 x10-*

4 9x t0-u 3 x t0-'

3 x 10** 3 x10-8 1 x10-e l 1129 8 e x t0**

2 x10-8 1x10-8 f x10-" 8 x 10-'

l 7x 10-* 8 x t0-e 1 131 8 2x10-' E x 10-*

i 0 x 10** 8 x10-8 1 x 10* "

I l 3 x t0** q.

3 x 10-' 2x10-8 1x t0-e 4 x 10**

1132 S 2x t0** fx10-' 3 x10** 8 x10-e i

9x10-' 8x10-e ax10** 1x10-8 114 S 3 x 10** 2 x 10**

I 4x to-" t x 10-*

f x 10*' l x 10*

7x 10" 4x10

1 134 8 8 x 10*' 4 x 10** 8 x 10-' 2 x10-e 1 135 1

8 3 x 10** f x t0-' - 1 x 10-' 0 x 10-*

1 x 10 7 x 10-* 1 x10-8 4 x 10-8 8

Indum (171 4 x 10-' f x10-e t x10-e 7x 10-8 k 100 8 1 x 10-* 8 x10-8 4 x10-e t x 10**

i 4 x 10*' E x 10-'

192 8 1x t0-e Rx so-e 1 x 10-' 1x 10-8 4 x 10** 4 x10-8 8

3 x 10-' t x10-8 9 x 10-"

Ir 194 S 2 x 10*' 4 x10-* l 1 x 10-' 8 x10-8 3 x 10** 1 kon (26) i 2 x 10-' 9 x 10* *

)

Fe 55 5 8 x 10-' 3 x 10-' I 8 x 10-' 2 x 10-'

i 1 x 10-* 7x10-8 3 x10-e 3 x10-8 e x 10-* )

Fe 69 8 2x10-e i 1 x 10-' 2x10-8 8 x 10-'

8 x t0**

bypton (36)

Kr 85m 84 8 x10-8 8x10-e Ex to** 2 x 10-' exto * ' )

W B5 54 1 x 10-'

1 x 10-' 3 x 10**

W 87 Sut>

8

, 1 x 10** 2 x t o-*

W 08 - 82 1 x 10**

Lanthanum (50 La 140 8 2x to-' -

2 x 10-' 7 x 10-*- 8 x10-' 2x10

Leed (82) i 1 x t0-' f x 10-*

Pb 203 -- S 4 x 10-8 2x 10-e 3 x 10-* 1 x10-8 8 x 10-' 4 x10-8 Pb t10 6

2x108 1x10*8 8 x t0-8 4x10 *

$ f x 10*

4 x10-8 I 4 x 10- 1 x 10*'

2x 10-

8 x10-8 8 x 10-"

Pb rit S fx10-8 8x10-*

2 x 10-'

8x10-" Ex10-8 Lanetann (71) 8 f x t0-e 5 x 10-8 7x 10-" Ex10-8 Lu 177 8 8 x 10-' 3 x 10-8 2x 10-8 l 1 x 10'

Manganese (25' Mn 62 i

f x10-' 3 x 10-8 2x10-e 1 x 10"* j S E x 10-' 1 x 10**

8 f x10-' 3x10-8 1 x 10*' 8 x 10-* E x 10-'

Mn64 S 3 x 10-*

4 x10*' 4 x 10-* f x10-8 1 x 10-* '

1 4 x 10-8 3x10-e i xio-a g x gp-e Mn $$ & 8 x 10*' 4 x 10-8 3 x 10-' 1 x 10-*

Metcary (80) - I 6 x 10-'

Hg 197en S 3 x 10*

f x to-' 1x t0-8 7 x 10-' 8x10e 3 x 10** 2x10-8 8 8 x 10-' S x10-e 3 x 10-e f x 10-*

He 197 8 1 x 10-' 9 x 10*

8

+ 4 x 10-s 3 x 10-*

Ng 303 3 x 10** f x10-' e x 10"* 6 x 10**

S 7x 10*'

l 5 x 10** t x10 ' t x10'8 1 Motybdenum (42) 1 x 10*' 3 x 1d** 4 x 10**

Mo De S 1 x 10**

~~

7 x 10*

5 x10-e 3 x go-e y x io-e Noodpunum (ec) t f x 10*' 1x108 Nd t44 5 7 x 10-' 4 x 10"*

8 x 10*" Fx10 e I 3 x 10* "

g x ig-" f x t0

Nd t47-f x 10-e g x ig-u e x ip-e S 4 x 10-' 2x10-a g x ta-. 8 x 10-8 6 2 x 10-' 2 x 10** 8 x 10-'

Nd 149 8 2 x 10-*

8 x 10

8 x 10** 4 x 10-8 3x t0**

Neptunnnn'(93)- i 1 x t0-e 8 x 10-e gxg0 '

Np 227 4 4 x 10-" 3x t0**

9 x 10-* 1 x 10* " 3 x 10-*

I i x 10* " 0 x 10**

Np 239 8 4 x 10*" 3x10 8

8 x 10*' 4 x 10-8 3 x 10-'

I 1 x 10

Nckel (29) f x 10*' 4 x 10-' 2 x 10** 1 x t0**

Ni se 8 S x 10-' sx 10-8 2x 10-8 2 x 10**

9 9

em

t e

OUESTION G.8 (2.5)

In Accordance with the RADIOLOGICAL SAFETY RULES established for guidance of work with radioactive materials; (a) What four markings must be on Radi oac ti ve (1.0) materials or Radiation Sources when unattended 7 l (b) Above what source strength should material (0.5) i not be manipulated with the fingers 7 (t) At what general area radiation level must (O.5) j personnel monitoring devices be worn 7 (d) Under what two conditions should smoking, (0.5) eating, and drinking be stopped when working with radioactive materials ?

I 4 ANSWER G.8 (2.D)

(a) (0.25 each)

(1) magenta radiation symbol (2) words " CAUTION RADIOACTIVE MATERIAL" l (3) 1 dent i f i cat i on of substance 1

(4) magnitude of radioactivity (b) 0.5 uCi (c) 2 mrem /hr (d) (0.25 each)

(1) unseal ed radi oacti ve materi al s are in use or rtored (2) potential for surface contamination 4 REFERENCE Reed sop-52. Radi cat t i vre Mat er i el c ~ir ans4 er l

e-a E-_______________________________

I 4

I i'

DUESTION G.9 (1.5) l I

The Quality Factor (DF) concept makes it possible to express the energy dissipation of ionizing radiation in biological tissue in more meaningful units (Rem). The OF for gamma rays is one (1),

or, one Rad is equi vil ant to one Rem in terms of biological damage.

What is the OF for each of the f ollowing radiation types ? '

(0.5 pts. each)

(1) X-Rays (2) Beta particles I

(3) Alpha particles 4AN5WER G.9 (1.5)

( O.5 pts. each )

(1) 1 (2) 1 (3) 20 4REFERENCF Reed Training Manual, Chapter 1, pages 2 b --2 6 . and Chapter 2, pages 2-3 44****t44**444444444*44$44tts44444*t44t44*tt44444444**444444444*4 END OF CATEGORY G END OF EXAM 1

I l

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$ 0 0'

-- /f f Y f ANSWER KEY U.S. NUCLEAR REGULATORY COMMISSION 1 SENIOR REACTOR OPERATOR LICENSE EXAMINATION l

]

Facility: _ REED COLLEGE Reactor Type: TRIGA Date Administered: MAY 19, 1987

)

Examiner: THOMAS R. MEADOWS Applicant:

INSTRUCTIONS TO APPLICANT:

Use separate paper for the answers. Staple question sheet on top of the answer sheet. Points for each question are indicated in parentheses after the question.

The passing grade requires at least 70% in each category.

Examination papers will be picked up six (6) hours after the examination starts.

Category % of

% of Applicant's Category Value Total Score _Value Category u.v 20 C H. Reactor Theory is. c a.v

.efP^ ,-=-- W- I. Radioactive Materials Handling, Disposal, and u.v Hazards 20 iG J. Specific Operating u.v Characteristics .

{

20 W_ _

' ' - K. Fuel Handling and Core \

Parameters j u.e i 20 20 %

L. Administrative Procedures, a et conditions, and ifmitations Cr-~

TOTALS Final Grade %

)

All aid.work done on this examination is my own; I have neither given nor received-i Applicant's Signature i-

1

?

7 . 'n 'a 1, -

Ph .

i' I

e...- ,

REQUIREMENTS FOR ADMINISTRATION OF WRI1 TEN EXAMINATIONS -

",7 1. A single room shall be provided for completing the written examina-tion. The location of this room and supporting restroom facilities '

...%l shall be such as to prevent contact with all other facility end/or l s~ contractor personnel during the duration of the written examination. < l If necessary, the facility should make arrangements for the use of a suitable taining roomisatthe this room a responsib local school,ility of the licensee. motel, or other build 4;s ,-b,Q

2. Miriimum spacing is required to ensure examination integrity as o

determined by the chief examiner. Minimum spacing should be one l

' candidate per table, with a 3-ft space between tables. No wall i charts, models, and/or other training saterials shall be present in the examination room, r

3. Suitable arrangements shall be made by the facility if the candi- !

dates are to have lunch, coffee, or other refreshments. These ;

arrangements shall comply with Item 1 above. These arrangements shall be reviewed by the examiner and/or proctor.

4. The facility staff shall be provided a copy of the written examination and answer key after the last candidate has completed and handed in !

his written examination. The facility staff shall then have five working l days to provide formal written comments with supporting documentation on the examination and answer key to the chief examiner or to the regional office section chief. ;

'. 5.- The licensee 'shall provide pads of 8-1/2 by 11 in. Ifned paper in

. unopened packages for each candidate's use in completing the exam-ination. The examiner shall distribute these pads to the candidates.

, All reference material needed to complete the examination shall be e furnished by the examiner. Candidates can bring pens calculators, or slide rules into the examination room,, and pencils, no cther equipment or reference material shall be allowed.

6. Only black ink or dark pencils should be used for writing answers to questier.s. -

Examiner Standards 9 .

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NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS i:: -

f During the admin 1si. ration 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. 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. '

.i ,,:

W

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

4?

g g.hC.4

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

,. 1. - _

i 5.

[ Fill in the date on the cover sheet of the examination (if necessary).

h 6. Use only the paper provided for answers.

g.

r 7. Print your name in the upper right-hand corner of the first page of each

[, section of the answer sheet.

[r 8. Consecutively number each answer sheet, write "End of Category " as .

on a new page, write.only one side of appropriate, the paper, andstart writeeach "Last category' Page on the last answer sheet.

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

l

- l

10. Skip at least three lines between each answer.

, 11. Separate answer sheets from pad and place finished answer sheets face

t down on your desk or table. ,

7 e

i. - 12. Use abbreviations only if they are comonly used in facility literature.

1 i

t' 13. The point value for each question is indicated in parentheses after the I'

I question and can be used as a guide for the depth of answer requir,ed.

' 14. Show all calculations, methods, or assumptions used to obtain an answer

, to mathematical problems whether indicated in the question or not.

15. Partial credit may be given. Therefore, ANSWER ALL PARTS OF THE QUESTION AND 00 HOT LEAVE ANY ANSWER' BLANK..

16. If parts of the examination are not clear as to intent, ask questions of the examiner only.

17. You must sign the statement on the cover sheet that indicates istthe -

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. -

~

e Examiner Standards ,

a

f.

s. . ..

^

,. 18. When you complete your examination, you shall: .

M. .

a. Assemble your examination as follows: -

l' (1) Exam questions on top. .

~

(2) Exam aids - figures, tables, etc.

~

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

,, b. Turn in your copy of the examination and all pages used to answer the examination questions. ~

.g c. Turn in all scrap paper and the balance of the paper that you did I

,fg:ppr ;

not use for answering the questions.

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.

> l 4

. . i Examiner Standards .

EQUATION SHEET f = ma y = s/t w = mg Cycle efficiency = Net Work (out) a = v,t + at Energy (in)

E = mC a = (vg - v,)/t KE = my vf A = AN

= v, + at A = A,e PE = agh e = 6/t A = In 2/t = 0.693/t g W = vaP AE = 931Am t q(eff) = (t,;)(ty) .

(t +t) 3 j Q = [nCp6T -YX '

I.Ie k=UAAT I.Ie~VX Pur = Wg In ~K/ M I-1 9 10 P=P 10 5UR(t)

TVL = 1.3/p P=P o et /T HVL ='O.693/p SUR = 26.06/T T = 1.44 DT SCR = S/(1 - K,gg)

IA *ff DI SUR = 26 g,,l CR

= S/(1 - K,ggx)

T = '(1,fp ) + {(f p)/xeff)

P CR (1 - K f) = CR (1 ~K ff) 7 . t*/ (p p M = 1/(1 - K,gg) = CR g/CR0 I"( ~ 8)! A eff D M = (1 - K 8"I eff~ )! eff

AE /K eff)0 /(1 - Keff)1 l eff eff Sp3 . (1 geff)/K,gg p= ~

[ L*/TK,gg .] + [E/(1 + A,ggT )] ,

t* - 1 x 10 seconds P = I4V/(3 x 10 0) A,gg = 0.1 seconds" .

I = No 1d3y=Id22 VATER PARAMETERS Idg =Idy2

,1 gal. = 8.345 lbm R/hr = (0.5 CE)/d (meters)

I gal. = 3.78 liters 3 R/hr = 6 CE/d (feet)

I ft = 7.48 gal.

MISCELLANEOUS CONVERSIONS .

Density = 6.2.4 lbm/ft 3 1 Curie = 3.7 x 1010 dps Density = 1 gm/cm 3 1 kg = 2.21 lbm Heat of va;orization = 970 Itu/lbm I hp = 2.54 x 103 BTU /hr Heat of fusica = 144 Btu /lbm 1 Hw = 3.41 x 106 Btu /hr 1 Atm = 14,7 psi = 29.9 in. Ig. I Btu = 778 ft-lbf 1 ft. H O 2 = 0.4333 '1bf/in 1 inch = 2.54 cm ..

F = 9/5 C + 32 "C = 5/9 ( F - 32)

CATECORY H REACTOR THEORY

~~

QUESTION H.1 (2.5)

Concerning the production of source neutrons:

(a) What are the two (2) types of radionuclides reactions associated with the irradiation of a light target nucleus, such as Lithium, that produce source neutrons ?

(0.25 pts. each) (0.5)

(b) What is the other category of neutron sources associated with the decay of a heavy nucleus, such as Pu-240 or Cm-244? (0.5)

(c) Why ir it important to have neutron sources in Reeds' reactor core, specifically upon reactor startup after a long down period? (1.0)

(d) What type of installed neutron source (specific isotopic composition) is used for the Reed TRIGA reactor? (0.5)

ANSWER H.1 (2.5)

(a) alpha-neutron (0.25) photo-neutron (0.25)

(b) SF - spontaneous fission (0.5)

(c) To ensure that nuclear power can be accurately monitored in the range of the fission counter count rate channel s.

(also accept: Control Rod withdrawal is prevented with less than two neutron induced cps on the startup channel). (1.0)

(d) Polonium - Beryllium h e.rc' " " '; A-de) (0,5)

(Plutonium)

+ REFERENCE Reed Technical Specifications, page ?

Reactor Physics, Module 12-1, pages 7-8 Reed SAR, page 5-5 sqr ec t , *e c-~r c- r ea- in* Z.C.

H -- 1

QUESTION H.2 (0.5)

Which statement, from the choices presented below, correctly defines THERMAL NEUTRON :

(a) A neutron that experiences no net change in energy after several collisions with atoms of the moderator.

(b) A neutron at resonant epithermal energy levels.

(c) The primary source of thermal energy increase in the reactor core during reactor operation.

(d) A neutron at epithermal energy levels that causes fission to occur in Pu-240 or U-238.

ANSWER H.2 (0,5)

(a)

+REFERENEE Reactor Physics, Moc'ul e 12-3, paces O-9 Stephensen, R. McGraw-Hill ;

H-2

OUESTION H.3 (3.5)

The Reed TRIGA reactor has been designed with a large prompt negative fuel temperature coefficient (FTC)..Concerning the three (3) principle effects that collectively achieve this negative FTC; Doppler, Cell and Inhomogeneities, and Core Leakage:

i (a) How does DOFPLER contribute to the negative FTC ? (1.0)

(b) How do CELL and INHOMOGENEITIES contribute to the negative FTC ? (1.0)

(c) How does CCRE LEAKAGE contribute to the negative FTC ? (1.0)

(d) Which of these three(3) eff ects is largest ? (0.25)

(e) Which of these three(3) effects is smallest ? (0.25)

ANSWER H.3 (3.5) l (a) With increasing fuel temperatures the reconance absorbtion bands of U-238 &. PU-240 broaden which increases the probability of a non-fission capture of a fast neutron (by U-238 or Pu-240). (1.0)

(b) With increasing fuel and Zirconium Hydride temperature the thermal neutron population is hardened (increased energy) ther eby decreasing the probability of absorbtion and fission in U-235. Due to the non-homogeneous core construction, ,

,~

this increases the probability of thermalization and '

absorption in the surrounding water. (1.0)

(c) With increasing fuel and Zirconium Hydride temperature the 1 thermal neutron population is hardened (increased energy) i thereby increasing the average distance a thermal neutron diffuses. The increased thermal neutron-track length allows i an increase in the core leakage. (1.0)

(d) (b) (0.25)

(e) (c) (0.25)

REFERENCE Reactor Physics, Module 12-6,page 6-1?

Stephenson, R. McGraw-Hill H-3

1

DUESTION H.4 (3.0)

A sheet of gold, 0.01 cm thick, is inserted in a neutron beam, and a flux measurement of 640 n/cm^2-sec i s obtained. When the foil is removed, the flux-reading promptly increases to 880 n/cm^2-sec.

Given:

(1) density of gol d = 19.32 gm/cm^3 (2) atomic weight of gold = 197 (3) Avogadro's Number = 6.023 x 10^23 atoms /gm.at.wt.

What is the microscopic removal cross section of the gold specimen for this particular neutron beam 7 (SHOW ALL WORK) (3.0) ,

1

AN5WER H.4 ( :_4 0)

F i r e.t c on.pu t e 11 (gold atomc/cm'3)(1.5 pte t o t. a l ) :

liv Au density -

fwogadro"c Number '

. Atomic Weight ( 1. 0 )

= .J2. %." -

10^26 at ons /c m ^ 3 (0.5) nelection of correct relationship: (0,5) i 1=10 c -N(microccopac croce rec t i on ) X (r Te o cW) 1

-os- l I: Ices-gx :/zwe f .: .<v ed \

yCorrect e p p'l l c a t i on : (1.0) l

/#

zr s re-r/c 3 \

1 640 = 880 e -22,92. .; (mi c r osc op i c cross section): . 01 (e- /

f

,o"""%

In(640/880 = -22.923,g(microscopic cross section)n . 01 (<- -)

In .727 = .229(microscopic crose ret ti on ) / '# L "#

microscopic crats section= .320/(.229e/0 # #) [d]

, microscopic cross section= 1.39[ x v" ch ~

~

o /~ O m r ; c/ : s.39 rs,"*'u Z #

t / s ., ~ 2 4REFERENC.E o- e ve z ^ > * ' ' ' ' /'""#

Reector Phytico, Modu)e 2,pages 22-24 -

e . o e v 4 - -: + .r Stephenson. R. McGraw-Hill p [ *- c. r , <. n

~se, coraccr ,# vtre.-racu ) (i.e.,)

f c z ag- gen [ (m e n e - Se w'c c. t e rs ficranl, *

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QUESTION H.5 (2.0)

The Reed reactor is taken critical and maintained on a stable 40 second period. How long will it take to increase power level 1 two(2) decades ?

ANSWER H.5 (2.O) i SUR = 26/T =26/40 = 0.65 DPM (0.5) l l

1 P=Po 10^ SUR(t), P/Po = 10^ SUR(t) ]

P/Po= 100(2 decades)= 10^ GUR(t)

['Mc: 20 /uo

'"#" "'# '~

(1.0)

" = SUR(t) i e s - sa we'")

l \

t = 2/.65 = 3.1 minutes (0.5) l i ;

-or-P = Po e^ t/T (0.5)

P/Po = 100 = e^ t/40 sec h ( 1. O) t= In 100 (40) = 184 sec = 3.1 minutes (0.5) ,

l

< REFERENCE i l

Reactor Physics, Module 5 Stephenson, R. Mc Gr aw--l ii l l equation sheet I

l H-5

~

QUESTION H.6 (1.5)

Assume the Reed reactor core is at criticality when 0.05%

reactivity 'is added via control rod withdrawal.

~

What is the resultant transient Start Up Rate, before the coefficients of reactivity begin to stabilize the reaction ?

(assume 21 K/K) (1.5)

{eff=0.0072

+ ANSWER H.6 (1.5)

SUR = 26 ( 1 eff 4 I:::/K ) / ( f eff - 4 K / f': ) ( 0. 5)

SUR = 26 ( O.1 x 0.0005) / (O.0072 - O.0005) (1.O)

= .19 dpm

REFERENCE Reactor Physics, Module 5 Stephenson, R. McGr,9w-Hill ecuation sheet H-5

. i 1

l 1

QUESTION H.7 (3.5)

The Reed reactor is shutdown by 5% delta K/K, with a count rate (CR) of 10 cps, after a two week maintenance period:

(a) How much positive reactivity would have to be added to' double the count rate ? (1.5) l (Express your answer in terms of delta K/K - Show All Work)

(b) How many dollars of reactivity ($) would the value obtained l in question (a) be worth? (Assume Beff = 0.0075) (1.0) I (c) Why is the value of Keff INDEPENDENT of initial source generated neutron counts ? 1 (1.0) I l

+ANOWER H.7 (3.0) l l (a) CR2/CR1 = 1-K1/1-K2, CR2/CR1 = 2 2= 1-K1/1-K2 K2 = (K1 + 1) /2, K1 is approximately, 1 --0. 05 = 0. 95 K2 = (0.95 + 1)/2 = 0.975 delta K/K (1.0)

Reactivity added = 0.?75 - 0.95 = 2.5 % delta K/K (0.5)

(b) $ = ( delta K/K)/ Detc ef f ective (0,5)

(f ull credit for $ relationship to delta K/K) assuming Beta effective = 0.0075:

$ = .025/.0075 = 3.33 dollars of reactivity (0.5) t (c) Keff (the neutron life cycle) only considers fission neutrons in the sel f -sust ai ni ng fission reaction. (1.O? !

REFERENCE Reactor Physics, Modules 4 and 5 equation sheet H-7

l 1

QUESTION I H.8 (1.0)

What is the reason for the 80 second period (-1/3 DPM SUR), which lasts for approximately 15-20 minutes following a reactor scram?

(1.0)

ANSWER H.O (1.0)

T h t: 80 second period is determined by the longest delayed neutron precursor half-life ( 54.5 seconds for Br-87 ). (1.0)

REFERENCE Reactor Physics, Module 5, pages 10-11, 24 equation sheet i

i l

l H-- 8

QUESTION H.9 (1.0)

Why are burnable poisons added to TRIGA reactor _ cores upon initial core loading ?

ANSWER H.9 (1.0)

(

So that more fuel can be added to the reactor core upon initial core load ( without adding additional rod worth ).

.l

+ REFERENCE l

Reactor Physics, Module 12, pages 23-24 l l

i l

l l

l i

i H-9 i

e r

QUESTION H.10 (1.5)

Regarding Figure H-10, an illustration of Reactor Power verses Time in hours:

At t = 0 hours0 days 0 hours 0 weeks 0 months a reactor startup from Xenon free conditions to 100% power occurs.

At t = 70 hours8.101852e-4 days 0.0194 hours 1.157407e-4 weeks 2.6635e-5 months a reactor trip occurs, followed by a reactor startup to 100% power at t = 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months .

(a) Sketch the Xenon reactivity response in the core that results from these power changes. (0.5)

(b) At approximately what time will Xenon first reach eqilibrium concentrations for 100% power ? (0.25)

(c) At approximately what time will the maximum concentration

( " MAX Peak") of Xenon occur ? (0.25)

(d) At approxin.ately what time will the maximum rate of rod motion occur in order to off-set the Xenon transient during the reactor startup ? (0.25)

(e) Will this rod motion (needed to off-set the Xenon transient during the reactor startup) be IN or DUT ? (0.25)

. ANSWER H.10 (1.5)

(a) See the attached key. (0.5)

(b) 40 to 50 hours5.787037e-4 days 0.0139 hours 8.267196e-5 weeks 1.9025e-5 months (0.25)

(c) 75 to 80 hours9.259259e-4 days 0.0222 hours 1.322751e-4 weeks 3.044e-5 months (0.25)

(d) 92 to 87 hours0.00101 days 0.0242 hours 1.438492e-4 weeks 3.31035e-5 months (0.25)

(80)

(e) IN (0.25)

REFERENCE Reactor Physics, Module 12-7, pages 14-27

... ~ ~ ........ ~ . ~ ~ ~ ... . ~ .. ~ ... ~ - ....... . ~ .

END OF CATEOORY H l l

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7 CATEGORY I Radioactive Materi als Handling , ;

Disposal, and Hacards ;

l

QUESTION I.1 (2.5) 10 CFR 20 specifies limits for personnel monitoring: _

(a) How does 10 CFR 20.202, " Personnel monitoring",

define a RADIATION AREA? (0.5)

(b) How does 10 CFR 20.202, " Personnel monitoring",

define a HIGH RADIATION AREA? (0.5)

(c) 10 CFR 20.105 identifies three (3) dose limits that specify maximum permissible levels of radiation in j UNRESTRICTED AREAS: ]

I What are these three(3) maximum permissible dose limits ? (0.5 pts. each) (1.5)

ANCWER j I.1 (2.5)

(a) (Any area, accessible to personnel, in which there exists radiation, at such levels) that a major portion of the body (or whole body) could receive in any one hour a dose in excess of 5 Mrem, (0.25) '

-or-In any 5 consecutive days a dose in excess of 100 Mr em. (0.25)

(b) (Any area, accessible to personnel, in which there exists radiation, at such levels) that a major portion of the body (or whole body) could receive in any one hour a dose in excess of 100 Mrem. (0.5)

(c) (1.5 pts., 0.5 pts each)

(1) (Not likely to receive) a dose to the whole body, in any period of one calender year, in excess of 0.5,M em.

p --

(2) (Radi ati on levels which, if an individual were continuously present in the area, could not result in his receiving ) a dose in excess of 2 Mrem in any one hour.

(3) (Radi ati on levels which, if an individual were continuously present in the area, could not result in his receiving ) a dose in excess of 100 Mrem in any seven consecutive days.

+ REFERENCE 10 CFR 20, Reed Training Manual. Chapter 2, pages 39-40 I-1

1

QUESTION I.2 (4.0)

A Chemistry professor is giving a long lecture / tour in Reed's reactor room to a group of male reactor operator candidates. The radiation level over the reactor pool is 5 rem /hr (f or the purposes of this discussion). Assumming that no one in the group, including the professor, has had no rr> cent occupational exposure to radiation over the present calendar quarter:

(a) How long can the professor and his class remain in the vicinity of the reactor pool without exceeding their 10 CFR 20 quarterly whole body limit ? (1.0)

(b) How long can the professor, without exceeding the 10 CFR 20 quarterly limit for his hands, handle an irradiated sample j that reads 3.5 Re of Beta on contact ? (1.0) n.

l 4

(c) If one of the groups' members were under eighteen years of I age. How long could he remain with the tour in the vicinity 1 of the reactor pool, without exceeding the 10 CFR 20 limit I for a minor? (0.5) l (d) One member of the party is 19 years old and has accumulated 3 Rem of exposure over the prior 3 quarters. How long may he J remain in the vicinity of the reactor pool and not exceed the lifetime limit for occupational exposure? (1.0) i l

(e) What program or principle outlined in 10 CFR 20, if carried out at Reed, would not have allowed a long lecture / tour in a I radiation field such as that described above? (0.5)

( see a n s.w e r key on next onge )

i l

l l

I-2

F

)

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4 ANSWER ]

I.2 (4.0) 1 (a) Quarterly Limit = 1.25 rem (0.5) time = E (1.25 rem)/(5 rem /hr)30 60 min /hr 3

= 0.25 hr, or 15 minutes (0.5)

(b) Quarterly Limit = 7.5 rem (Skin from Beta) (0.5) 35 time = E (7.5 rem)/(2Crem/hr)3E 60 min /hr ]

= fart". 'i h r . or P5 minutes (0.5) 2 . 2' s29 (c) Limit is 10% of shortest stay time ( Whole Body ) (0.25)

[ whatever limit used in part (a) will be accepted in the below calculati on 3 time = E (1.25 rem)/(5 rem /hr)30 60 min /hr 3410%

= .025 hr, or 1.5 minutes ,(0.25)

(d) Must use 5 x (N - 18) (0.5)

Exposure not to exceed 5 :. (19 -18) = 5 Rom (0.25) 5 Rem - 3 Rem = 2 Rem Therefore time = E(2 Rem)/(5 rem)3E60 min /hr3 =

= 0.4 hr or 24 minutes (0.25)

(e) ALARA ( as low as reasonably achievabl e)

(any reference to this concept will be accepted) (0.5)

REFERENCE 10 CFR 20 i Reed Administrative Procedures, pages 2-14 l Reed sop 17 Reed Training Manual, Chapter 2, pages 18-20 l

I-3

1 1

OUESTION I.3 (3.5)

An unshielded sample of a radia-isotope is observed to cause a radiation level of 0.75 R/hr at a distance of one(1) foot. This material is known to emit a single 2.0 Mev gamma photon.

l (a) What would the dose rate be (in Mrem /hr) from the j same sample at a distance of 4 feet ? (1.0)

(b) How many curies of the radio-isotope are present ? (1.0) i (c) Assumming that the half value layer of lead is 1/2 inch, )

what thickness of lead shielding will be required to ]

reduce the dose rate from the sample to 75 Mrem /hr >

at a distance of one (1) foot ? (1.5)

ANSWCR I.3 (3.5)

(a) D2 = D1 (d1/d2)^2 (Q=1) (0.75)

D2 = 750 Mrem (1/16)

= 46.9 Mrem /hr (0.25)

(b) R/hr at one foot = 6x Ci x nv E (0.75) 0.75 = 6 n Ci n 1.0 x 2.0 i Ci = 0.75 / 1/12 = 0.063 curies (0.25) l (c) I = Io x 2 (exp-n)[ number of half thicknesses] (0.75) 75/750 = 2 (exp-n) 10 = 2 (exp n)

In10/1n2 = n n = 3.32 (0.5) 3.32 y 1/2 = 1.7 inches (0.25)

~"

(Calculation may also be done with I = Io x e and HVL =

0.693/J,.)

+ REFERENCE Reed Training Manual , Chapter 2, pages 21-28 I

I-4

l l

)

i

QUESTION 1 I.4 (2.0)

Concerning sources of radiation : _

(a) Which decay mode (choose only one) listed below is most likely to occur for Nitrogen-16 ? (1.0) 1 1

(1) T(1/2) = 23.7 min / beta + decay /no gamma J (2) T(1/2) = 1.55 hr/ alpha decay /no gamma (3) T(1/2) = 38.5 sec/ beta- decay / 1-2 Mev gamma (4) T(1/2) = 7.35 sec/ beta- decay / 6-8 Mev gamma (b) Which decay mode (choose only one) listed below is most j likely to occur for Argon-41 ? (1.0) l (1) T(1/2) = 23.7 min / beta + decay /no gamma l

(2) T(1/2) = 1.93 hr/ beta- decay /1-2 Mev gamma (3) T(1/2) = 38.5 sec/ alpha- decay / no gamma (4) T(1/2) = 5.75 sec/ beta- decay / 6-8 Mev gamma

-l l

l l 1

+AN5WER I.4 (2.0)

(a) (4) T (1/2) = 7.35 sec/ beta- decay / 6-0 Mev gamma (b) (2) T(1/2) = 1.85 hr/ beta- decay /1-2 Mev gamma l

I l + REFERENCE l Reed Reactor Operati ons Gemi nar , Oct.27,1986 Chart of the Nuclides, General Electric l

I-5

O I l

l

)

QUESTION ,

I.5 (2.5)

(a) The Quality Factor (DF) concept makes it possible to express the energy dissipation of ionizing radiation in biological tissue in more meaningful , units (Rem). The QF for gamma rays is one (1), or, one Rad is equivilant to one Rem in terms of biological damage.

What is the QF for each of the following radiation types for l an internal dose?

(1) X-Rays (0.5) 1 \

l (2) Beta particles (0.5) '

(3) Alpha particles (0.5)

(4) Neutrons (0.5)

(b) Besides X-Rays, which one(1) of the other three (3) radiation types listed in part (a) above, is most penetrating to the l human body ? (0.5)

ANSWER I.5 (2.5) l (a) ( O.5 pts. each ) (2.0)

(1) 1 j (2) 1 (7) go (sav .e e e C ' ., /0)

(4) 10 (b) Neutrons (0.5)

+ REFERENCE Reed Training Manual, Chapter 1, pages 25-26, and Chapter 2, paces 2-3<

~

)

p , . cp 7n ,aivo A n^ t , h /csssneen , p., ,

, .9, , ,

1-6

O l

l

(

)

QUESTION I.6 (1.5)

Considering radiation detection:

Figure I.6 illustrates the pulse size verses applied voltage for typical gas filled detection chambers. NAME each of the indicated j regions. ( 0.25 pts. each )

(a) Region I (b) Region II l (c) Region III (d) Region IV (e) Region V (f) Region VI WANSWER I.6 (1.5, 0.25 pts. each )

[ eny reanonable statement that identifies the associatec regions

application will be accepted J (a) Region I, Recombination (b) Region II, Ioni z at i on (c) Region III, Propor ti onal (d) Regi on IV, Li mi t ed Proportional (e) Region V, Geiger - Muller (f) Region VI, Continuous Discharge

REFERENCE Reed Training Mcnual. Chapter 2, pages 3C' "iD I-7

I

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8 I

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j 2088 -

! I II; I s 1 1 I j 2 088 -

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3 u 3: - In - v -

3 108 Yt -

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> ~ 204 -

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~ -

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- ~ e 1 0 Ve Va Vs Vs

. V8 Curve 1:

Curve 2- Radiation event of lower specific lonization.

Radiation event of higher specific Ionization.

Figure I.6 0

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1 1

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1

QUESTION I.7 (1.0)

Why would radiation damage to the genes of a somatic cell NOT be classified as a genetic ef f ect, or, genetic damage 7 (1.0) ]

+ANCWER l 1.7 (1.0)

The term genetic damage, or, genetic effect refers to the effectr> l caused by <:hromosome and/or gene) autaticns in the egg or sperm )

(reproduct , . a) cel l s.

l (Genetic effectc of radiation damage are those ef f ects which can be transmitted to a f uture generati on. )

+ REFERENCE Reed Trai ning Manual , Chapter 2, page 12 l

1-G I

t i

I

QUESTION I.B (1.0) ,

i Concerning the maintenance and operation of the continuous air monitor ( CAM ) :

(a) For what radiation type does the Radium - 226 source calibrate the CAM ? (0.25)

(b) For what radiation type do the Uranium - Oxide sources calibrate the CAM ? (0.25)

(c) Reed Technical Specifications require that a CAM be l operable in the reactor room during reactor operation.

Commensurate with Reed CAM calibration procedure, sop-30:

What other monitoring device satisfies the intent of this requirment when the CAM is down f or short term maintenance? (0.25)

(d) How often must the CAM's alarm setpoints be verified, as stipulated by Reed Technical Specifications 7 (0.25)

ANSWER I.C (1.0, 0.25 ptc. ecch)

(e) gamma j d '"# O ' ""_ ' #'

(b) +.e ./"

(c) Gaceous Stach Monitor (GSM) 1 l

(d) once every week

+ REFERENCE 1 Reed Technical Specifications, page 4 l Reed sop-du, Calibration of the CAM l

l l I-9 l

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G- r:; w ca c e ?rr r,e e m ys ,4

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~

QUESTION f I.9 (2.0) i Concerning Federal Department of Transportation regulations for packaging and transportation of radioactive materials : l <

I (a) What is the limit (specification) for removable j contamination is considered insignificant f or shipment of I radioactive materials ? (0.5) j (b) What is the dose rate limit (specification) that requires a 4

" WHITE radioactive I lable" to be affixed to the packaging of radioactive materials f or shipment ? (0.5) t (c) What are the two(2) dose rate limits (specifications) that require a " YELLOW radioactive II lable" to be affixed to the i

{ packaging of radioactive materials f or shipment ? (0.5) I I

(d) What is the dose rate limit (specification) that requires a I

( " YELLOW radioactive III lable" to be affixed to the j j packaging of radioactive materials f or shipment ? (0.5) q

( +ANDWER ,

I.9 (2.0) ]

ca) 2,200 eps/iOc sq. em. ( 0. m 1

(L) < 0.5 mR/hr at the surface (0,5)

)

J (c) (1) 10 mR/hr at the surface (O.25) i (2) c O.5 mR/hr at one meter (0.25) i I

I (d)

> 10 mR/hr (0,5)

, + REFERENCE Reed sop-52, Rad 2oactive Materials Transfer, 52.10 Appendi:- t l

l

++ u w4 e

m n o *+* u u **+ zw* n n u ++ n o

u u **** n o n ++ n *** o !

END OF CATEGORY 1 l l I-10 1

CATEGORY J Specific Operating Char etteri sti c s

QUESTION J.1 (3.0)

Considering the operation of the Irradiation Facility (Lazy Susan):

l (a) The G.A. TRIGA Mark I Reactor Mechanical Maintenance and Operating Manual cautions that, " if any pin fails in any coupling in the drive system (manual drive handle, upper shaft coupling, and sprocket pinion), DO NOT replace it with a stronger pin ".

(1) What is the reason f or this caution ? (1.0)

(2) What action should the operator take if a drive system coupling pin does break 7 (1.0)

(b) The principal advantage of using plastic specimen containers is the small amount of induced activity after irradiation.

Why is the post irradiation activity of plastic so low (as compared to aluminum) ? (1.0)

> A*JCWER 1 J.1 (3.0)

(a) ( 1.0 pt. each)

(1) These pins are derigned to be progressively stronger l so that if failure occurs, it will probably be in an ecceccibl e area. (1.0)

(2) Determine what caused the pin to f ail (0.25), and reduce the torque land /or friction) on the assembl y (0.75).

(b) This is due to the low (l ower ) neutron acti vati on cross section of plastic. (1.0)

+ REFERENCE G.A. TRIGA Mark I Reactor Mechar,i cal Maintenance and Operating Manual, page 31 J-1 l

+ QUESTION l J.2 (3. 0 )

In accordance with Reed sop-51, Performing Rabbit Irradiations:

(a) What is the maximum specimen irradiation time allowed at full power ? (0,5)

(b) During rabbit irradiation it is possible that a specimen might add or remove core reactivity.

What are two(2) indicators, available to the reactor operator, that identify reactivity changes during j irradiation operations as unreasonable, and indicate j that the reactor should be SCRAMED ? )

(1.0 pt. each) (2.0) )

l (c) If the ion chamber reads a significant dose while j the rabbit is still in the terminal, the rabbit should not be removed from the terminal.

What is considered a "significant done" with the rabbit still in the terminal ? (0.5)

+ANOWER l J.2 (3.0) 1 (a) 5 minutes (:h5)

(b) (1) A reactivity change of 10% (1.0)

(2) A sudden increase or decrease of 100 control (1.0) rod positions i l

(t) gr eater thar 10 mR/hr (0.5)

REFERENCE l Reed sop-51, Performing Rabbit Irradiations 3-2

l

+ QUESTION J.3 (2.0) j i

Commensurate with Reed operating procedure, sop-03, startup and I core. excess check: l (a) Where are the three(3) places that the reactor operator should check, before startup, to identify irradiation J requests currently in the core? (0.5 pts each) (1.5)

(b) During the withdrawal of the shim rod, at what operating condition should the operator ease off the shim rod up button when a period gr c;tre than 15 seconds is achieved ?

tr'/ (0.5) i

ANSWER l J.3 (2.0) I (a) (1.5 ptc., 0.5 pts. each )

(1) former loc book entries l (2) the e::p er i ment status board ;

l (3) the clipboard hung on the console room north wall l

( labled " Experiments Currently in the Reactor ") {

(b) As the reactor goes from a subtritical to a supercritical cond) tion.( when critical ) (0,5)

+ REFERENCE 4 Reed top-03, startup and core eucess check f 1

J-3

1

\

DUESTION J.4 (2.5)

Commensurate with Reed operating procedure, sop-04, Going Up In Power:

~

(a) What percent of linear channel full scale indication (approximately y) is the range switch stepped up during a reactor startup? (0.25)

(b) With the exception of the Safety rod, no rod should be removed greater than 95% of its full length.

What is the reason for this requirement ? (1.25) .

1 (c) How long must the reactor power be steady, with stable control rod position, before the core excess can ;

be calculated accurately? (0.5)

(d) When must the reactor be placed in automatic mode? (0.5)

+ANCWER 1 l

J.4 (2.5)

(a) 75% (0.25)

(b) To assure that the rod is kept in the steepect port of its calibration curve (maintain the rod's worth high) (1.00), such that a cmall cmount of rod insertion will result in the maximum decrecce in reactivity (maintain better control of reactor power) (0.25). (1.25)

(c) greater than two(2) minutes (0.5)

(d) Whenever the reactor is >90% of rated power (250 KW) (0.5) j

+ REFERENCE Reed sop-03, Going Up In Power i 1

J-4

1 i

< j

. i

QUESTION J.5 (0.5)

What is the preferred mode of reactor operation that supports a pre-planned MANUAL scram, as delineated in Reed sop-08, " SCRAMS"7 i

ANSWER J.5 (0.5) l J

steady state made

REFERENCE Reed sop -OS, "CCRAMS" l

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QUESTION J.6 (3.0)

I Reed *s Saf ety Analysis Report identifies six (6) scrams. Two (2) of these are: .-

(1) Power level channel, compensated ion chamber, "micromicroammeter". l (2) Manual. ,

l 1 What are the other f our (4) scrams ? ( 3.0, 0.75 each )

+ ANSWER ;

J.6 ( 3. 0, 0.75 pts. each)

(a) Power level channel, ion chamber ( ad.justable by cperator from 20% to 110% of rated power ) [u r-eva )

(b) Reactor period channel ( adjustable between infinity and

+ 3 second1 ) [s en e scro . rex / m )

fs rx x " < >

(c) Consol e oower circuit f ai l ur e . [t. .e.r e e <~os.rver s'--e4 ) l l

(d) Ion - chember power supplyfailure[p, p ., f ,s y,,, 7-o c g,

+ REFERENCE l Reed SAR, page 5-16 7~,rr rg /> m x /< / Acseren 7- rrn te"7' N "" M' d M " rr M'""' , <~"- /, g;>s 7,-g /r 7, e # , /*. / </ ,

1 l

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J-6

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+0UESTION J.7 (3.0)

Figure J.7 ( attached ) illustrates the operating ranges of the "eactor neutron detectors.

(a) What is the type of channel, and/or type of instrument, used for each of the indicated ranges of reactor operation identified by the labled bar graphs A, B, and C ? (1.5)

(1.5, 0.5 pts. each)

(b) What is the one(1) safety interlock associated with j the channel used for reactor operation in the range l identified by the labled bar graph A ? (1.5) I

( 1.0 point for interlock ) i

( O.5 point for setpoint of interlock) {

+ ANSWER J.7 (T.0) l I

(a) see attached Figure J.7 - KEY : 1.5) i (b) Control element withdrawal is prevented with !

a count rate below a preset value. (1.0)

The preset value is less than two(2) neutron induced cpc ( on the Etartup Channel) (0.5)

REFERENCE G.A. TRIGA Mark I Reacter Mechanical Maintenance and Operating Manual, Appendix B, page 13 Reed Technical Specifications, page 9 j

I J-7

D 9e i

30' 9 -

10 '

8 -

10 7 _ -

30 ios _ , -

l 25FIO _ I

. g ,

10

, Uncompensated

.lon Chamber 7 tok -

Percent Power h (Steady-State

$ Operation)

W 10 3 _

M a: .

g 10 2 . Pc -

goSC/$EC e.

s, I -

1O 0- .

e :

I 10 10

I~ --

A i

~

10' --

SOURCE LEVEL 10'3 l

4 lC/SEC

~

10 Operating ranges of reactor neutron detector

[ s*G e.1 &~ [, 7 *

. 1 i . .

I 10 .0 2 X 109W 109- ~~

i 10 107-

.- - GAMMA l 10N CHAMBER l PEAK POWER (PULSE POWER)..

6 _

10 SAME CHAMBER 25 xio" ._

3 10 l 4

- Uncompensated Ion Chamber O go4 - i Percent Power !

h (Steady-State E

d --

Operation) g to 3 a

K k

, 10 2

goSC/SEC COMPENSATED 10N CHAM 8ER O, f

-- LINEAR RECORDER (STEADY-STATE OPERATION)

I ~

10

.0 COMPENSATED 10N CHAMBER o,f 0 - LOG n RECORDER

10 '~

(STEADY-STATE OPERATION) l 10*I

~

-- -^

FIS$l0N COUNTER COUNT-RATECHANNEL}p.f io __

. SOURCE LEVEL 10~3 IC/SEC

~

IO Operating ranges of reactor neutron detector '

r-/c e.~rt .7. 7 _ /f t r t

___..___m_________= _ _ _ _ _ _

i.

QUESTION J.8 (3.0)

Commensurate with Reed operating procedure, sop 33, Control Rod Calibration n (a) What is the power level at which a critical condition is~

established, before doubling power for i ndi vi dual rod calibration? (0.25)

(b) How long must the power level be held (stabilized) at the established critical condition, before doubling power for individual rod calibration? (0.25) a (c) Why must integral rod worth data f or the shim and saf ety rods be doubled to obtain an accurate representation ? (1.0)

(d) After the worths of the individual control rods have been analyzed, how is reactor shutdown margin determined (identif y the f ormula v ed) 7 (1,0)

(e) As speci fied in this procedure, what is the minimum shutdown margin with which the reactor can be operated ? (0.5)

+ ANSWER J.E (3.0)

(A) 7 Watte (0.25)

I (b) 5 - 7 minutec (0.25) i (c) When determining the integral rod worth of the shim and saf ety rods, data can only be obtained for the top hal f of the rod (0.5). It i s assumed that the calibration curve is symmetric through the mid rod position, therefore the data is doubled (0.5). (1.0)

(d) (1.0) shutdown margin = worth of shim + worth of reg - core encess (0.33) (0.33) (0.03) !

1 l

(e) 0. 4 % delta K/K ( O.53 dollars ) ( 0. 5 ) i I

+ REFERENCE Reed operating procedure, sop 33, Control Rod Calibration i

- A***+tt*********+******++*+H**+++*++++**++**+*+*****4***+*++++.x END OF CATEGORY J ,

i l

J-8 1

l CATEGORY K Fuel Heneling and Core Perameters

QUESTION K.1 (3.0)

The Reed facility has in place f our (4 ) radiation monitors that are capable of detecting a fuel element failure in the reactor core or storage pool, and subsequently initiate the evacuation alarms and/or ventilation confinment system.

What are these f our (4) radiation monitors and their alarm l setpoints? (0.5 pt. for each radiation monitor)

(0.25 pt. for each radiation monitor setpoint)

'aANSWER K.1 (3.0)

ALARM (0.5 pts.eech) SETPOINT (0.25 pts.each) l (a) CAM 2000 cpm (b) RAM 2 mR/hr (c) Gaseous Stack Monitor 115 cpm [e /f- / tv c w)

(d) Particulate Stack Mcnitcr 1500 c p m [,ze c> -nes c ~ }

REFERENCE Reed Emergency Implementation Procedures, page 2 and Appendir D ]

i K-1

l

DUESTION K.2 (1.0 )

The G.A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual cautions that while handling fuel elements with the fuel handling tool , to never coil the control cable in a circle with a diameter of less than about 2 feet.

What is the reason f or this precaution 7 i l + ANSWER j j K.2 (1.0) l A tight coil will pull the inner wire of the centrol cable and may release the fuel element.

REFERENCE G.A. Triga Mark I Reactor Mechanicc1 Maintenance and Operating Manual, page 99 l

l i

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4

QUESTION K.3 (1.0)

There are two (2) conductivity prrbus in the water system.

(a) What function does Probe "A" provide by sampling the water conductivity upstream of the demineralized ? (0,5)

(b) What function does Probe "B" provide by sampling the water conductivity downstream of the demineralized ? (0.5)

I

+ ANSWER K.3 (1.0)

(a) High conductivity in the procecs flow leading from the reactor tank it an indication of a fuel element failure (also, a integrity failure of an i:t-core enperiment) . (0.5)

(b) High conductivity in the process flow leading from the demineralized is an indication of depleted resin (and/cr improper demineraliter operation such that the resin fails). (0.5)

+ REFERENCE G. A. Trige Mark I Reactor Mechanical Maintenance and Operating Manual, section 5 K-3

1 4

9 6

+ QUESTION K.4 (2.0 )

Neutron reflection occurs in both vertical and axial in-core 1 I

directions: .

(a) What component provides neutron reflection in the vertical ( ax i al ) direction within a TRIGA core ? (1.0)

(b) What component provides neutron reflection in the .

hori:: ental (radial) direction within a TRIGA core ? (1.0) t

(

+ ANSWER !

K.4 (2. O) I l

)

l (a) Fuel el en.en t graphite end sections (1.C)

(b) Graphite reflector around the core (in ci r cul ar .

sealed aluminum. container) ( 1. O ) j i

+ REFERENCE j C.A. Triga Mark I Reactor Mcchanical Mair.tenance and Oper+.t:ng l Manual, Sc: tion 3 i l

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l I

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l K- 4 L____---____.__________________ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _

DUESTION I

K.5 (3.0 )

Considering TRIGA reactor core design:

(a) How is the weight of the Reed reactor core transmitted to the bottom of the pool ? (1.0)

(b) How does cooling water pass between the fuel elements )

and the upper grid plate ? (1.0) j I

(c) What is the motive f orce that circulates the pool water troughout the core 7 (1.0)

+ ANSWER K.5 (3.0)

(a) The bottom grid o] ate Et:pports the core (0.75).

The grid plate is welded to the reflector container, which rests on the pool bottom (0.25). (1.0)

(b) Cooling water passes through the area between the (triangular) spacer b l oc l: on the tcp of each f t. c l element and the round holes in the grid plate. (1.0)

(c) Natural Circulation (1.0)

+ REFEREtJCE G.A. Triga Mark I Reactor Mechanical Mai ntenance a r. d Operating Manual. Section 3 l

\

K-5

9 l

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QUESTION K.6 (3.0)

Reed's Safety Analysis Report (SAR) addresses systems that relcte to the safe operation of the reactor and design of the core. One ,

of these systems is the control rod drive system: -

(a) What design feature reduces bottoming impact of the control rods when they are scrammed ? (1.0)

(b) According to the Reed Technical Specifications, what is the i maximum rate of reactivity insertion associated with the movement of a control rod 7 (0.5)

(c) Commensurate with Reed Technical Specifications, what is the maximum control element drop time that a rod may have and still be considered operable ? (0.5)

(d) What is the vertical travel length of the control elements? (0.5)

(e) What is the maximum design rate of insertion and/or withdrawal that can be developed by the regulating rod drive motor ? (0.5)

ANSWER K.6 (3.0)

(a) The contral rod eEEembly barrel hac grated vent s in the bottcm providing a dashpot action wnon the rods are scrammed. (1.0)

(b) 0.12 % delte K/K - set (0.5:

(c) (lest than) one ( 1 ) second (0,5)

(d) 15 inchen (0,5)

(e) 24 in./ min (Will accept appropriate Units f rom red position indication.) (0.5)

+REFERENEE G. A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual, Section 3 Reed Technical Epecificationc, pages 2-4 Reed SAR, pagen 5-G through 5-10 K-6 i

4

DUESTION K.7 (3.0)

Reed 's saf ety analysis specifies the design of the reactor core and its control systems:

(a) Reed's Technical Specifications require that the maximum available core excess reactivity shall be 2.25 %

delta K/K. This requirement assumes four(4) core operating conditions exist. One ( 1) of these is that reactivity experiments are in place.

What are the other three(3) core operating conditions assumed by Technical Specifications when analyzing maximum available core excess reactivity ? (0.5 pts.) (1.5) each (b) Commensurate with Reed's SAR, what are the approximate reactivity worths of each of the following control i rods ? (0.5 pts, each) (1.5)

(1) shim (2) safety (3) regulating

1. NSWER K.7 (3.0)

(a) ( 1.5, 0.5 pts. each )

(1) cold core (2) Xenon free (3) critical (b) (1.5, 0.5 pts, each )

l</. ? f (1) shim, 2 . u ,. al e ; P-lv'. t*

(2) safety, 2 r *' A i t u. i:./i ?

Y /-' 5" (3) regul ating , 1 deH-e -t'.fr ,

l

+ REFERENCE Reed Technical Specifications, pages 2- 4 Reed SAR. pagen 5-0 through 5-10 g es v, n e .e 7 e en .r re . e n. w r. m cs, s vs. w s < sees-~<'* " "I" K-7 l

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QUESTION K.B (2.0)

Reed's Technical Specifications identify three(3) conditions that define the reactor as " SHUTDOWN",

with fixed experiments in place. One of these is that the console key is in the OFF position and that key is removed f rom the console under the control of a reactor operator (or locked up).

What are the other two(2) conditions that specify when the reacter is " SHUTDOWN" ? ( 1.0 pts. each ) (2.0)

+ ANSWER l

K.8 (2.0, 1.0 each)

(1) Gufficient control rods are inserted to assure that the reactor is subtritical by a margin greater than O.7% delta K/K ( cold, Xenon free).

(2) No work is in progress involving fuel handling (0,5) (or refueling operations) or mai ntenance of control mechanicms (0.5).

REFERENCE Reed Technical Specifications, Definitions i

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QUESTION K.9 (2.0)

Regarding the reactor pool, bridge, and fuel storage :

(a) What is the minimum pool water level for reactor operations, as defined in Reeds

Technical Specifications ? (0.25)

(b) Reed's G.A. Triga Mark I Reactor Mechanical Maintenance and Operating Manual identifies two(2) reasons for maintaining this operating pool water level.

What are these two(2) reasons ? (0.5 pts, each) (1.0)

(c) At what bulk pool temperature must the reactor be shutdown ? (0.25)

(d) How many fuel elements can EACH of the fuel storage racks hold ? (0.25) 1 (e) All fuel elements or f ueled devices shall be stored such that criticality will not occur in the storage pool.

Commensurate with Technical Specifications, what is the maximum Keff allowed in the fuel storage pool under all conditions of moderation ? (0.25)

ANSWER K.9 (2.0)

(a) 16 feet above the top of the grid plate (0.25)

(b) (1) Provide for proper ski mmer operation

( provi de NF'SH to the water pump ) (0,5)

(2) provide proper shielding (0.5)

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~r c*s) ,a,sese se~ , -

sser- c 2) r .m o . r # r ; +'~< n % P "' ' , * ~ , , , , , , ,

(c) 120 degrees F

/ . o m ,. , n , ,,s,

.} (O*"5)

/ (d) 10 (0.25)

(e) Keff less than 0.0 (0.25)

REFERENCE Reed Technical Specifications, regen 24:

G.A. Triga Mark I Reactor tiechanical Maintenance

\ and Operating Manual, pages 26a and 81

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\ END OF CATECORY K

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l CATEGORY L.

Administrative F'roceduren, Conditione and Limitation

DUESTION )

L.1 (2.0)

Commensurate with 10 CFR 50.59, Changes Tests and Experiments: I What are the two (2) conditions that WOULD require NRC approval before implementation of changes to Safety Analysis Report (SAR) related procecures, Tests, and Experiments 7 ( 1.0 pt. each )

+ANGWER L.1 (2.0)

(1) If it invol ven a change to the Technical Specification incorporated in the license. (1.0)

(2) If it involven en unreviewad cafety question. (1.0)

+ REFERENCE l 10 CFR 50.59, Changes Tests and Experiments i

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QUESTION L.2 (1.0)

Who.is the chief administrative person, with the ultimate responsibility for the safe and competent operation of the Reed Reactor Facility ?

+ ANSWER L.2 (1.0)

The Director of the Reed Reactor Project [s . f,- s eccy f, f,,,,,,,,,,]

+ REFERENCE Reed Administrative Procedures, page 2 L-2

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QUESTION I L.3 (3.0) )

The Reed Emergency plan lists Five (5) levels of emergency l classification. Two(2) of these, Site Area Emergency and General Emergency, are NOT used at Reed. -

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(a) What are the other three(3) levels of emergency )

classification that are used at Reed? (2.0)

(b) What is the boundary of the Emergency Planning Zone f or the Reed Reactor Facility 7 (1.0)

ANSWER L.3 (3. O) l (a) ( 2.0, 0.66 pts. each )

l (1) Non-Reactor Safety Related Event (2) Unusual Event (3) Alert (b) The boundary is defined as the reactor bay or reactor containment area. (1.0)

+ REFERENCE Reed Emergency Plan l

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CUESTION L.4 (1.0)

Concerning the design and operation of the facility, commensurate with Reed Technical Speci f i cati ons (a) What is the maximum steady-state operational power level

! specified by the Reed Facility operating license 7 (0.5) l (b) What is the maximum steady-state power level for the purpoe of testing the 110% full power safety circuits, specified by 1 the Reed Facility operating license? (0.5)

+ANGWER L.4 (1.0)

(a) 250 L:W (utilizing Table I and II scrams and inter 1cti:s) (0,5) l l

(b) 207.5 I:W [stsv / < < < -r , y f v /c s") (0,5)

+ REFERENCE Reed 1echnical Speci 4 i cati ons

/Ttro .r psc -n tw c. 4 # c t"h! -

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+ QUESTION L.5 (2.0)

Reed Technical Speci fications i dentif y two(2) ~reactor condi ti ons that constitute (define) an "EXFERIMENT".

What are the two(2) definitions c4 " EXPERIMENT".

( 1.0 pts. each )

+ANOWER L.5 (2.0)

(1) Any appar atus, (devi ce, or mater i el ) i r.ctal l ed in the core (0,5) or experimental facilities (0.25), which i n not a normal part of these 4acilities (0.25). (1.0)

(2) Any operation otsigined to measure reactor parameters (or characterictact). (1.0'

REFERENCE Reed Technical Specifications L- 5

N e

QUESTION L6 (3.5)

Considering the administrative limits on conducting in-core experiments at the Reed Reactor Facili ty, which comply with Reed Technical Specifications:

(a) What is the reactivity worth that would require an individual experiment to be fastened, in order to prevent movement during reactor operation? (0.5)

(b) Which administrative organization at the Reed Facility evaluates the safety aspects of new experiments, before they are implemented? (0.5)

(c) What is the maximum reactivity worth of any individual in-core experiment? (0.5)

(d) What is the maximum reactivity worth of the total amount of in-core experiments, including potential reactivity from experimental mal f uncti on. (0.5)

(e) What three(3) types of experimental materials must be doubly encapsulated? ( O.5 pts. each ) (1.5)

+ANOWER L.6 (3.5)

(c) $1.00 (0.5)

(b) Reactor Operations Committee (ROC) (0,5)

(c) 31.35 ( 0. 5 ) i (d) $2,00 ( O . L. i (e) (1.5, 0.5 pts.eech) ( 1. 5 )

(1) corr osi ve to reactor components (2) compoundr highly eactive wi th water l (3) (liculd) f i ssi onabl t material j

+ REFERENCE Reed Technicc1 Spet l f i c ati on s l

L-6

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+DUESTION L.7 (1.0) ,

I I

Associ a'.ed with any emergency related to an irradiation experiment, the MPC of radioactive Iodine and Strontium isotopes j is of major concern in Reed 's Saf ety Analysis Report. !

Commensurate with Reed Technical Specifications:

(a) What is the maximum total inventory of Iodine isotopes 131 and 135 in each fueled experiment? (0.5)

(b) What is the maximum total inventory of Strontium - 90 l

in each fueled experiment? (0.5) l

+ ANSWER l 1.7 ( 1. 0, 0.5 pte.each) l 1

(a) 1.5 curies (b) 5 millicuries

+rtEFERENCE l Reed Technical Specification l

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+ QUESTION )

L.8 (2.5) :

1 1 Technical Specifications identif y the duties of the l

Reactor Operations Committee:

(a) What individuals comprise the Reactor Operaticns Committee (include their qualification requirements) ? (1.5) i i (b) To what individual does the Reactor Operations Committee f directly report? (0.5)

(c) How often is the ROC required to meet every year to review facility operations ? (0.5)

+ANOWER L.8 (2.5)

(a) The ROC is compoced[of a minimum of four memembers of,)the facility staff (0.5), including the reactor supervisor l (0.5), and a qualified Health Physicist (0,5). (1.5)

(b) Precident of Reed College ('ve, 0 Secern ) (0.5)

(c) twice (0.5)

REFERENCE Read Technical Specifications Reed Administrative Procedures l l l \

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QUESTION L.9 (2.5)

During an irradiation experiment the rabbit operator withdraws a het specimen completely out of the core. While removing it f rcm i

the receiver he slips on the specimen, knocking himself _

l unconscious. The evacuation al arm initiates, and the facility is l subsequently evacuated in accordance with Reed's Emergency Implementation Procedures. The exposure rate at the Rabbit Receiving Station is 75 R/hr. You are acting as the Et1ERGENCY I COORDINATOR, and authorize reentry in order to save the unconscious technician's life.

l (a) Where would you assemble Facility personnel after the evacuation, pursuant Reed's Emergency Implementation Procedures? (1.0) l (b) How long can your rescue team remain at the Rabbit Receiving Station without exceeding their maximum dose allowed by Reed's Emergency Implementation Procedures? (1.5) l ( O.5 point f or identif ying the limit)

( 1.0 point for the time calculation )

AtJEWER L.9 (2.5)

(a) reactor parking ar ea (1.0) l (1) l i mi t = 25 rccm [ej 7f'F) (0.5)

(2) Quality factor R/ rem for gamma = 1 time = 25 rem /( 75 R/hr) = .33 hour3.819444e-4 days 0.00917 hours 5.456349e-5 weeks 1.25565e-5 months = 20 min. (1,0)

REFERENCE h W A'h Reed's Emergency Implementation Procedurec, pages 13 - 14 l

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DUESTION L.10 (1.5)

An accident involving severe f uel damage or the failure of an experiment that results in releases of radioactivity constitutes I an ALERT emergency action level, if certain alarm conditions are reached on f acility gaseous radiation monitors.

One(1) of these four(4) conditions is that the reading on the Air !

Particulate Monitor reaches 100 x alarm level . !

What are the other three(3) air monitor alarm conditions l that would indicate an ALERT emergency action level, upon a j major radioactivity release? (0.5 pts each) 4 ANSWER l i

L.10 (1.5, 0.5 pts. each) j l

(1) Gaseous Stack Monitor - 100 : elarm level (2) C AM - 100 ) alarm Ievel (3) A radiation Area Monitor Alarm lasting one htur from an unexplained source.

+ REFERENCE Reed's Emergency Implementation ProcedureE, Teblt I

+*+ ,x++ <**+.o r n *++ ,##**4+ +x+<*.>+++*4* w o + + #** **#*44#5 n >+#*+ n e END Or CATEGORY L END OF EXAM I

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L-10 i

ML20235E523

Text

Reference:

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