IR 05000020/1988004
| ML20195E035 | |
| Person / Time | |
|---|---|
| Site: | MIT Nuclear Research Reactor |
| Issue date: | 10/19/1988 |
| From: | Eselgroth P, Yachimiak E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20195E034 | List: |
| References | |
| 50-020-88-04OL, 50-20-88-4OL, NUDOCS 8811070224 | |
| Download: ML20195E035 (123) | |
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U.S. NUCLEAR REGULATORY COMMISSION REGION I j OPERATOR LICENSING EXAMINATION REPORT i r
EXAMINATION REPORT NO. 50-020/88-04 (0L) !
FACILITY DOCKET NO.50-020 FACILITY LICENSE N0. R-37 l LICENSEE: Massachusetts Institute of Technology 138 Albany Street
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Cadridge, Massachusetts 02139 FACILITY: Massachu;etts Institute of Technology Reactor (MITR-II)_
EXAMINATION DATES: September 12 & 13, 1988 i
CHIEF EXAMINER: [ t/ /d / Ob Edward Yachtmiak Uperaf,1ons Engineer I) ate APPROVED BY: [#//V #+8hr/ ////f/88 I tertter EselgrotMrsief PWR 5ection gate
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i l SUtHARY: Written and operating examinations were administered to One (1)
Senior Reactor Operator (SRO) candidate and One (1) Reactor i Operator (RO) candidate. Both candidates succesfully completed :
their respective examinations and were granted license l
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REPORT DETAILS TYPE OF EXAMINATION: Replacement EXAMINATION RESULTS:
1 SR0 l R0 I l Pass / Fail l Pass / Fail l l l l 1 l l l l Written i 1/0 l 1/0 l 1 I I I I I i l l Operating l 1/0 1 1/0 l l I l l
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I I I I l Overall 1 1/0 l 1/0 I
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I I I I CHIEF EXAMINER AT SITE: E. Yachimiak, USNRC OTHER EXAMINERS: D. Silk, USNRC 1.0 Generic Strengths The following generic strength was noted during the administration of the operating examinattens. This information is bting provided to the licensee in recognition of the efforts of the Nuclear Reactor Laboratory (NRL) staff to adequately train and qualify their NRC license candidate Both candidates displayed a thorough knowledge of the security plan which has been implemented at the MITR-II. Each candidate briefed the examiners on the confidentiality of the security plan and explained the limited "need to know" nature of the security system. Each candidate was familiar with the immediate and follow-up actions for security violations, as specified in the procedures, and was able t discuss each action in detai .0 Personnel Present at the Exit Meeting J. Bernard Otrector of Operations, MITR-II 0. Harling, Director of Nuclear Reactor Laboratory K. Kwok, Superintendent, MITR-II
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Attachments:
1. R0 Written Exastination and Answer Key 2. SR0 Written Examination and Answer Key 3. Facility Comments on the Written Examination 4. NRC Response to the Facility Coments
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Facility Comments on R0 Exas, 12 Sept. 88
A.02 Source is not installed.
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A.04 At 298 kW, . the temperature change is still insignifican The period would still be 60 second (Note PM 2. 3 p. 3 does give 100 kW as the point of adding hea We shift to cooling tours at 250 kW and begin seeing temperature ef fects
- on the approach to 1 M PM 2.3 p.3 is in error.)
3.02(a) Also, avoid activation of argon, and Pr6 vide inert madium for transport of disassociated D2 /02 to
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recombiner.
] C.04(c) Answer should be 'In'. On flooding, which would be with D 2 0 j a positive reactivity addition is mad (If light water
- flooded it, the answer is correct, but the blister tank is
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surrounded by heavy water.)
I i D.03(e) Must have 1800 spa for full power operatio For 100 KV operation, not required.
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E.03(a) Should be flow ' guide' not ' shroud'.
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E.03(b) Typo ' bank' should be ' tank'.
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l E.07(c) Current setpoint is 95 gp It varies, but is always above i sinteus required of 75 sp T.03(d) Refer to PH . 2.1 and FM 5.5.4. Neither requires an (amedi-l T.03(e) ate shutdow Both allow time to investigate and both l require shutdown by ARI if certain conditions exis Not i sure how these should be answered.
. G.05(b) NY-83 and MV-64 are referred to as the ' solenoid valves'.
, Memorisation of valve numbers is not required.
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Facility Comments on SRO Exam. 12 Sept._1988 H.01a Concur that ~4 > 8 because of their lower birth energie As a result they have a lower probability of undergoing fast neutron leakage and to a lesser extent resonance captur So, we agree with giving credit for "lower birth energies".
We disagree with giving credit for 'cause thermal fission'
because once thermalized both prompt and delayed have same probability of causing fissio H.02b The MIT Reactor uses fully enriched fue There is very little U-238 and hence little plutonium buildu Beta-effec-tive does decrease on the MITR-II with core life because the blades are withdrawn further making the ef fective core volume large Hence, there is less leakage of prompt neutron Recall that from fH.0la, the principal difference be tween prompt and delayed neutrons is the leskoge probability. Any-thing that decreases leakage decreases that differenc ,
H.03a It is not necessary to use startup rat Problem could be solved directly (and more easily) using perio H.04a Reason given in answer (less broadening) is correct but the '
effect is to deeresse (not increase as indicated in the answer) the capture cross-sectio Also, MITR fuel tempera- '
ture varies only over a range of 30'C from aero to full power. So, the ef fect is quite smal H.05h By definition, the shutdown nargin is calculated by subtract-ing out xeno So, the answer should be 'No Change'. If the question meant "by how much would the reactor be shutdown", 6 1 then the answer is ' Increase'. (Notel Believe this point of i confusion was discussed by the examiner during the test.)
H.08 Question should provide value for specific heat of wate ;
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I.0la Typo in answe It should be ' level' not ' flow' greater than '
900 gallons (not gpa).
I.02 The sump systen was recently modifie There is now only one pum .0Ab Typo on unit Should be 0.189 ca /2 gram. Hence, in solu- t tien, multiply by density instead of dividin Answer is !
about 2 c .09b Note Director of Operations and Energency Director may be !
the same perso k l
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J.05a The 13.8 KV breakers are the property of the Cambridge Electric Compan The Reactor Staff is not allowed to operate the Hence, question is not relevan J.10 Also provides shutdown cooling (decay heat removal) when reattot is shutdown. This is a fifth function of the cleanup sys ex RSM 3. .
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K.Olb Answer is correct but note that fuel must go from the storage I ring to the baske It can not go direct from the storage rin K.02 Currently two types.of boxe One is aluminum-r k a-1 aluminua, the other is cadmium-line '
K.06a A 1.8% delta K/K insertion will make the reactor prompt critica The answer should be that such an insertion will not cause a transient that is beyond the capability of the
- safety system to shut d9wn the reactor before fuel damage occur K.04 The answer is correct be question's wording is confus-ing. The safety and opes i n ' site aunt be verified before going above 1 K The S aperintendent sign for doing
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that evaluation.
j K.09s Also, radially symmetric.
K.09b The MIT Reactor does not use burnable poisons.
I K.09c Answer is correct but inserts are currently made of boron
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L.02b Also, minimum reqaired equipment is provided by self-contained power supplie L.03 Answer given is correc However, please see also PH 5.5.7,
"Building Overpressure", which gives other factors involved in selecting the set poin L.06 Must be two licensed reactor staff members, one of whom holds an SRO license for Class B. For Class C, could be two staff members, one of whom has an SR L.08 Attachment P'o was PM 4.4 page 1- These pages provide general advice and they are not the EALa given in the proce-dure Hence, this question is dif ficult to grad Comments are as follows:
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(1) An H 2 release would be an even The probability of problem has been increased, but no radiacion release has '
occurre ,
(2) A waste tank rupture would be an aler A radiation release has occurred, it is limited in extent by the finite tank volume, and it is well below levels for site emergenc Waste tank activity is never more than a few mil 11 curies, if tha (3) This is an event as per written MITR procedures (The EALs).
(4) Not classifie Falls within scope of A0P ..
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ATTACHMENT 4 NRC Response to the Facility Consnents A.02 Coment is valid and point count will be distributed as indicated in the answer shee The aaswer sheet anticipated this commen A.05 Coment is accepted. Answer key will be change B.02a Coments are accepted. Answer key will be changed to includc these answer C.04c Coment valid. Answer key will be change D.03e Comment valid. Answer key will be change E.03a Coment accepted. Answer key will be changed. Suggest change be made to Reactor Systems Manual p. E.03b Coment valid. Answer key will be change E.07c Coment accepted. Answer key will be change F.03d The question states that no other abnormal condition occurred, therefore F.03 (d) answer is NO 3HUTDOWN REQUIRED (error in answer key).
F.03e The question states that no othe'.* abnormal condition occurred, therefore F.03 (e) answer is NO SHUTDOWN REQUIRED (answer key is correct).
G.05b Coment is accepted. Answer key will be change H.01a The answer key was changed to: "because delayed neutrons have lower
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birth energies (0.50) which results in fewer delayed neutrons from being]
[0.50 lost from the neutron cycle during the thermalization process H.Olb The question was deleted due to the lack of a referenc The value of the question was reduced by 0.50 point H.03 Either method is acceptable and since the answer does not change, no change was made to the answer ke H.04a No changes were made to the answer key. The answer is correct, (Increase), since at the resonance energies the capture cross section Increases at lower temperatures. refer to Figure 4-2 ~
l-2-H.05b The answer key was not changed because the candidate was informed during the examination that Actual Shutdown Margin was "the amount by which the reactor would be shutdown."
I.01a The answer key was changed to: "level -
900 gallons." Please revise RSM-8.20 to correct this erro I.02 The answer key was changed and the value of the question was reduced by 0.50 points. Please revise RSM-8.19 and any applicable drawing I.04b The answer key was changed to reflect the typo in this questio The correct answer is 2.15 c I.09b The answer key was not changed because the reference material indicates only two (2) individutis: the Director of Reactor Operations (DRO) and the Radiation Protection Officer (RPO).
However, if the full emergency organization is activated, then the DRO is the Emergency Directo J.05a The answer key was not changed because the 13.8 KV circuit breaker motor-driven interlock is one of the loads which is directly supplied off the 125 VDC battery suppl J.10 The answer key was changed to include a fifth correct answer:
"provides for decay heat removal."
K.02 The answer key was changed to accept both answers for full credi K.06a The answer key was changed by deleting the non-required, bracketed portion of the answe The answer is still correct since the SAR shows that a 1.8% delta K/K is the limit for a step reactivity insertion without fuel damage occuring.
K.09a The answer key was not changed because axially syinmetric is the only answer which could be reference K.09b The question was deleted thereby reducing the value of the question by 1.5 points. Please revise RSM-1.4 to reflect this non-use of burnable poisons, i
K.09c The question, if used in the future, will be revised accordingl L.02b The answer key was not changed because a reference for the alternate answer was unavailabl L.03 The coment was reviewed but all other alternate answers did not have adequate justification to qualify them as a basis for the scram setpoint. The answer key was not change e
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-3-L 06 The answer key was not changed since the Class B criteria are more stringen L.08 The question should have included PM-4.5, "Emergency Action Levels."
L.08a and L.08b will be deleted because of inadeqaute informatio The value of the question was reduced by 1.00 point .
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i AITACHMENT 1 h hCa3yn a
U.S. NUCLEAR REGULATORY CUMMISSION PEACTOR OPERATOR LICENSE EXtEINATION
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Theility: _
MITR-II Reactor Type- Research Date Acainistere /09/12 Examiner: _
Gordon Robinson Candidato: 7 7100 TFA INSTRUCTIONS TO CANDIDATE
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Use separate paper for the answers. Write answers on one side only. Staple l question sheet on top of the answer sheets. Points for each question are indi-cated in parentheses after tne question. The passing grade requires at least 705 in each categoay. Examination papers will be picked up six (6) hours after the examination start .
Category % of Candidate's % of '
Value Total Score Cat. Value 1 .5 Principles of Reactor Operation 1 .0 Features of Facility Design 1 .5 General Operating Characteristics 1 .5 . Instruments and Controls 14.0, 1 Safety and Emergency Systems 1 .5 Standard and Emergency Operating Procedures
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1 .0 Radiation Control and Safety 1Q,Qd,
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Final Gr.de %
! All work done on this exam is my ow I have neither given nor received aid.
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i candicate's signature i
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NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS
)uring the administration of this examination the following rules apply
. . Cheating on the examination means an automatic denial of your application
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cnd could result in more severe penaltie . R3stroom trips are to.be limited and only one candidate at a time may 1 Cav You must avoid all contacts with anyone outside the examination rcom to avoid even the appearance or possibill.ty of cheatin Une black-ink or dark pencil gnty to facilitate legible reproduction Print your name in the blank provided on the cover sheet of the Cxaminatio . Fill in the date'on the cover sheet of the examination (if necessary). Use only the paper provided for answer *
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Print your name in the upper right-hand corner of the first page of each ocction of the answer shee :. Consecutively number each answer sheet, write "End of Category __" as copropriate, start each category on a new page, write gnig gn gne side of the paper, and write "Last Page" on the last answer shee Number each answer as to category and number, for example, 1.4, '
. Skip at least 3hcgg lines between each answe . Separate answer sheets from pad and place finished answer sheets face down on your desk or tabl . Une abbreviations only if they are commonly used in facility litetatut ,
3. The point value for each cuestion is indicated in parentheses after the
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Question and can be used as a guide for the depth of answer required.
i 4 Show all calculations, methods, or assumptions used to obtain an answer to math'ematical problems whether indicated in the Question or no Therefore, ANSWER ALL PARTS OF THE f 5. Pcrti al credit may be give QUESTION AND DO,NOT LEAVE ANY ANSWER BLANK.
[ ask questions of
' If parts of the examination are not clear as to intent, the examiner only.
I You must sign the statement on the cover sheet that indicates that the I 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 b en complete .
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18. When you complete your examination, you shall I o. Assemble your examination as followst
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(1) Exam questions on to .
(2) Exam aids - figur,es, tables, et the answe (3)
Answer pages including figures which are part of Turn in youp copy' of the examination and all pages used to ans&ter
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the examination question Turn in all scrap paper and the balance of the paper that you did not use for answering the question If after d. Leave the examination area, as defined by the examine l eavi ng , you are found in this area while the examination is still in progress, your license may be denied or revoke .
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. PRINCIPLES OF PEACTOR OPEPATION QUESTION A.01 (2.5)
(a.) Your reactor is subcritical by 4 percen t del ta K/ Your startup channel reads 30 cps. When the count rate has increased to 300 cps. , WHAT is the new K-effective. SHOW ALL WORK. Useful equations are appended to the end of the exa (2.0)
(b.) TRUE or FALSE? For a given amount of positive reactivity insertion while the reactor is sub-critical, the closer the reactor is to critical l
the larger the change in countrat (0.5)
QUESTION A.02 (2.0)
Two minutes after a scram of your reactor from full power, a significant number of r.eu trons are s t ill present in the cor List the major sources of these neutrons and state the origin of each sourc (2.0)
QUESTION A.03 (2.0)
l Indicate whether the following statements concerning tission product poi soning are TRUE or FALSE f or the MITR-I The amount of 9os:tive reactivity needed to over-come the eaullibrium value of xenon-135 poisoning at 100 percent of f 's 1 1 power is twice that needed to overcome equilibrium xenon-135 at 50 percent '
powe (0.5) Upon shutting down the reactor after an extended run at full power, the xenon concentration peaks approximately eleven (11) hours after shutdow (0.5) l When increasing power frcm 50 percent power ( at ter extended operation) to 100 percent power, the xenon-135 concentration i n i t i al l y decreases and then incr ease (0.5) Shutting down the reactor f r om f u l l power causes I
the samarium-149 concentration to chang (0.5)
s***** CATEGORY A C Ct 4T I NUE D CN NEXT FAGE + + + + + )
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- PRINCIPLES OF REACTOP OPEPATION ,
QUESTION A.04 (2.0)
During a normal startup ,s full p owe r htter several week s of maintenance, the reactor is placed on a 60 second perio The initial power is 100 watt With no rod movemen t , woul d this reactor period be sustained for 8 minu tes? ' Show your cal cul at i ons and JUSTIFY your answer . . (2.0)
QUESTION A.05 (2.0)
In a subcritical reactor, if a reactivity of 0.003 delta K/K is added to the reactor, will it take longer to reach equilibrium if the i n i t i al K-effective is 0.95 or if K-effective is 0.9957 Briefly Justify your choic (2.0)
QUESTION A.06 (?.0)
A cri tical reactor is placed on a stable reactor period at l ow p owe r . When measured with a stop watch, the doubling time was 35 seconds. WHAT is the approximate reactivity which has been inserted? SHOW ALL WORK. Useful ecuations See appended to the end of the exa (2.0)
QUESTION A.07 (2.0)
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Indicate whether the tollowing statements are TRUE or FALS ,
In general as shim blades are raised
- The axial spatial location of the point of maximum
- flux will be highe (0.5) The magnitude of the flux (in Part a.) will be increase (0.5) The magnitude of the thermal neutron flux available at the beam Dort reentrant thimble tips increase (0.5) Power density decreases in the A and B ring (0.!'
(+++++ END OF CATEGORY A +++++)
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~ FEAT RES OF FACILITY DESIGN QUESTION B.01 (2.5)
Draw a simple schematic of the Heavy Water Reflector Clean-up Syste Include the follanings All major component Indicate direction of f l ow be tween componen t (1.5) Location of outlet from the reflector tank and location of return to the main f l ow sys te (0.5) Location of all f l ow , temperature, and conductivity measuring device (0.5)
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OUESTION B.02 -(2.0)
Consider the Heavy Water Helium Gas Syste Give TWO (2) reasons WHY. helium is used instead ot air in this syste (1.0) WHAT TWO (2) operating conditions of the rec ombi ner ,
if met, assure that the deuterium concentration in the cover gas will not exceed 6 percent by volum (1.0)
OVESTION B.03 (2.0)
Briefly describe HOW normal shutdown cooling is obtained and WHAT operator actions must be taken to obtain maximum flo (2.0)
OUESTION B.04 (2.0)
Consider the Reactor Building Ventilation Syste WHY is it important to place the , witch that orovides loc al control of the mal;. Intake d6moer in the "Weekend-open" position whenever the build-ing is left unattended? (1.0) Briefly describe HOW the reactor building differential pressure is maintaine (1.0)
(***** CATEGORY B CONTINUED G4 NEXT PAGE ** ***)
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. . FEATURES OF FACI.LITY DESIGN QUESTION B.05 (1.5) ,
Briefly describe the THREE (3) step process used to seal a primary beam por (1.5)
QUESTI ON - B.06 (2.0)
Consid'er the reactor core configuratio ' Briefly explain the method used to number the fuel element positions in the three rings of the- ,
reactor cor (1.0) WHY are the fuel elements designed to be axially s ynet t r i c ? <!.0)
QUESTION B.07 (2.0)
In accordance with your technical specifications, indicate i the f ol l owi ng s Minimum primary coolant system flow rate at full ;
power operatio <0.5)
I Maximum power level with no primary coolant pumps in operatio (0.5)
- Max imum al l owabl e bul k pool temperature during full
' pcuer coeratio io.5) Minimum water level above core (you may use the -
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overficw pipe as a reference point if you wish). (0.5)
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C. GENEPAL OPEPATING CHARACTEPISTICS OUESTION C.01 (2.0)
l WHAT influences.the magnitude of the negative reactivity inserted when the heavy water reflector is -
dumped during a major scr am? Briefly explain WHY this
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change in magnitude occur (2.0)
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QUESTION C.02 (2.0)
The temperature coefficient et reactivity tor the MITR-Il encompasses TWO (2) distinct phenomena. Both insert nega-tive reactivity with an increase in temperatur Briefly-describe the reason for this reactivity change for EACH obenomeno (2.0)
OVESTION C.03 (1.5)
Indicate whether the following statements concerning primary system water chemistry are TRUE or FALS Con-sider each statement separatel It is permissible to operate the reactor if the pH value is in excess of 7.0 if the cause of the
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high pH is know (0,5)
- It is permissible to operate the reactor it the
- conductivity exceeds 2.0 micrombos when the ,
cause of the excess is known and is not related to the fuel or to the primary system's integrit (0.5)
i It is NOT permissible to operate the reactor if the chloride reading is in excess of 6 pp (0.5)
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C. GENERAL OPERATING CHARACTERTSTICS
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QUESTION C.04 (2.0)
During full power operation of your reactor WHAT change in position of the regulating rod, if any, will be required to maintain a constant power level if reactivity changes occur by the folluaing means: (Assume each ' change occurs independently.) ' Light water leaks into the heavy water reflecto (0.5) A l arge polye thelene sample is injected into the reflector tank reentrant thimble using the pneumatic tube assembly 2PH (0.5) The heavy water blister tank suddenly floods while operating with the medical therapy room in use with all shutters ope (0.5)
- A large piece of cadnium is injected into the graphite Jflection region using the pneumatic tube assembly 1PH (0.5)
OUESTION C.05 (2.0)
Give TWO (2) reasons WHY the regulating rod reactivi ty worth per inch withdrawn is greatest at the beginning of rod wi thdrawal (first inch withdrawn). (2.0)
QUCSTI ON C.06 '2.5)
During the previous week the reactor was operated at full power for six hours a day from Monday until Wednesday after-noo The follmaing Monday an additional sampl e was l oaded i n an or i f i ced sampl e assembl Briefly describe WHAT Information *
is required to obtain an estimated critical positio Assume no new fuel is adde (2.5)
QUESTION C.07 (1.5)
The fuel management pattern at the MITR-!! usually calls for refueling when the critical shim bank position reaches 16 inche Approx ima tel y WHAT is the core excess reactivity at this time? (0.5) WHY is this excess reactivity necessary? (1.0)
(***** CATEGORY C COVTINUED ON NEXT PAGE *****)
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- GENERAL OPERATING CHAPACTERISTICS
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QUESTION- C.08 (1.0)
Indicate whether the following are TRUE or FALSE: If in the process of refueling, fresh fuel is placed
, in the B-eing and partially-spent fuel ?s placed in .
I the A'and C-rings, the net result is to concentrate power in the center of the cor (0.5) Replacement of an orificed sample assembly with a fuel element increases the poner densety in the neighboring element (0,5) <
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- INSTRUMENTS AND CCtlTROLS l
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QUESTIG4 D.01 <2.5) Briefly describe HOW a fission--chamber detects neutron <1.5)
. Belefly describe HOW unwanted signals from gammas and alphas.are removed from the output signal of ;
fission chambe (1.0) ;
QUESTION D.02 (2.5)
During automatic operation, the regulating rod is driven
to the near-in positien by a slowly increasing reactivity transient (i .e. xenen buenout).
. Explain the reactor contro system's response i f no operator action is take (2.5)
QUESTION D.03 (2.5)
Indicate which of the f oll owi ng are interlocks which must ,
be satisfied in order to obtain initial blade motion
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(withdraw - permit interlocks):
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, Hol d-down gr i d l etched (0.5) !
' Two out of three of the Power Level Ch annel s !
(Channels 4 5, and 6) on scale <0.5)
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! Main tank at overflow .0.5)
, Inner and/or outer main lock gaskets pressure ;
switches closed (0.5)
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' Primary cool an t f l ow gr e a t e r than 1800 spm /0.5)
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D, INSTRUMENTS 41D CONTROLS
.
QUESTION D.04 (2.0)
The "SUB-CRITICAL POSITICN" interlock circuit provides a conuenient reference point at which the operator can pause to make a complete instrument check before bring-ing the reactor to criticallty. L i s t TWO -( 2) other reasons this interlock is incorporated into the shim blade control circui (2.0)
GUESTION D.05 (1.0)
WHAT ooerator action will cause the "WITHDRAW PERMIT CIRCUIT OPEN" scram al arm to ac t ivate wi thou t c aus ing the reactor to scram? (1.0)
QUESTION D.06 (2.5) Briefly explain WHY the reactor must be held at
. constant power twenty- four hours for thermal equilibrium to be reache (0.7) Once thermal equilibrium is reached, WHAT information is needed to calcul ate thermal power? (1.3)
GUESTION D.07 (1.5)
Briefly describe HOW the conductivity cell in the primary coolant measures the conductivity of the wate (1.5)
(***** END OF CATEGORY D +++++)
l
. TAFETY AND EMERGENCY SYSTEMS l
.
QUESTION E.01 (2.5)
Indicate if the electrical cads listed below WILL cr WILL NOT au t oma t i c al l y be supplied by the Emergency P >at r Distribution System if normal p owe r fails, Startup channel No. 1 (0,5) Rod control (0.5) Core purge blower '9.5% Magnet power (0.5) Primary coolant auxiliary pump (Ft12) (0,5)I OUEST!CN E.02 (1.5)
Indicate whether the f oll owing quest i ons concerni ng the Containment Pressure Relief System are TRUE or FALS This system is intended to be used to relieve all types of pressure buildup in the building centain-men ( 0 . 5 :a This system will automatically be actuated if the containment pressure reaches 2.0 psi (0.5% This system's charcoal filter is designed to absorb most (aporeximately 90 percent) of the lodine that may be present in the exhaust ai (0.5)
' OVESTION E.03 (2.5)
Consider Emergency Coolin flode 2 of Emergency Cooling assumes the level in the core tank cannot be maintained at t h e ov e r t i c4" level, but it has been determined that it is not drooping belcw the re ac tor inlet pene tr at i on . Erief1v describe the f i cda path through the
'I.0)
cort . Indicate the THREE (3) means by which heet is removed trem the crimsry syste (1.5)
(***** CATEGORY E C CNT I N U E D CN N E'<T PA G E + - * * * )
r
.
- SAFETY AND EMERGENCY SYST E QUESTION E.04 (2.5)
Consider the Main Core Tank Level Indicators (ML-3A and ML-38). Briefly describe the principle of operation and arrangement used to produce the main core tank level indication (1.5) Indicate the differences in operation of these level indicator (1.0)
OVESTION E.05 (2.0)
WHAT are the differences in circuitry, if any, between a scram caused by a short period and a scram caused by Icw primary coolant flo (2.0)
QUESTION E.06 (1.5>
In addition to dropping the shim bl ades. l i s t THREE (3)
other au tomat i c ac t i on s a M/4JOR SCRAM initiate (1.5)
QUESTION E.07 (1.5)
Indicate the SCRAM setpoints for the f ol l ow i ng s Reactor oeriod (0.5) Primary coolant l ow f l ow (0.5) Lcw heavy water flow ( 0 . " ';
(***** END OF CATEGORY E *****)
,, .
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f ??ANDARD AND EMERGENCY OPERATING RPOCEDURES
i g 0UESTION F.01 (2.5)
"
Consider the temocrary bypassing of a safety function NOT s required by Technical Specification ,
,
- If not part of an approved procedure, list the ,
THREE (3) people (by Job title) who should approve l the bypas (1.0) j
!
- WHAT THREE (3) actions must be taken after the i
,ohysical installation of a jumper? (1.5) l
'
l j QUESTION F.02 (2.0) !
Other than radiation monitors and their alarms, indicate I
,
'
TWO (2) likely indications of a fuel element cladding '
failure as given in AOP 5.8.2 ' Fission Product Detect- l ion in the Primary Cool an t" . (2.0)
l
'
) OVESTICN F.03 (2.5)
i s i For the below listed malfunctions indicate whether the l l iemediate actions r? quire a MAJOR SCPAM, MINOR SCRAM, SHUTOOWN BY ARI , or NO SHUTDOWN is required. Assume the
.
1 :
reactor is operating at full power and has not scrammed au t oma t i c al l y and that no o'ther abnormal conditions have ;
i been note ;
l
! A Period Channel Level Signal Of f-Sc al e Al arm l l occur ( 0. !;
i
, The Lew Fl ow Transf er Pump At arin occur (0.!) !
!
j The Low Fl ow Shi el d Cool an t A1 &rm occur (0.!) ' A Low Fl ow Aux i l i ary Pumo MM2 Alarm occur ( 0 . ! :- A Low Pressure Compressed Air Alarm occur (0.!) !
,
t
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I (++++* CATEGORY F CONTINUED ON NEXT PAGE *****) l i
i
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_ _.]
I
. ?TANDAPD cND Et1ERGENCY OPEPATING PPOCEDUPES
.
QUESTION F.04 (2.0)
A "High Pressure Reactor Inlet * al arm occur s ( AOP 5.2.11)
while your reactor is at full power. In addition to an increase in the heat exchanger outlet pressure, indicate FOUR (4) other conditions that, if any one of them exis require the operator to scram the reacto (2.0)
.
QUESTION F.05 (2.0)
In accordance with your Technical Specification definition, list the FOUR (4) types of reac tivi ty changes that con-stitute variable reactivit (2.0)
OUESTION F.06 (2.0)
A serious fire occurs in the control room while the reactor is at full powe In accordance with AOP 5. "Smoke Detector System", WHAT actions should the reactor operaton perform (if possible) prior to evacuating the contrcl room? (As3ume all required personnel have beeri not i f i ed. ) (2.0)
OUESTION F.07 (1.5)
Indicate whether the f ol l owi ng s t atemen t s concern i ng a normal hot weather reactor startup to tull power (SOP 2.3.1) are TRUE or FALS . If the reactor is not cr i t i c al when the shim ban.'
e<ceeds the estimated critical positten by inches, the shim bank must be l owe r e d to inches or more below the estimated critical (0.5?
positio When MW of reactor power is reached. a tive minute soak Deriod is maintained t o a l l ow the reactor core and primary cool an t to approach thermal equilibriu (0.5) Between 50 kW and 800 kW a 30 to 40 second period is recommended (0.7)
(*++++ END OF CATEGORY F +++.+)
- _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
,
-.
F
PADIATION CONTROL AND SAFETY -
OVESTION G.01 (1.5)
Does the biological effect of 10 Rem depend on whether it is a neutron or ganna dose?
Briefly explain your answe (1.5)
.
QUESTICN G.02 (2.0)
A radiation survey meter is located one foot kom a small single radioiostope sample and reads 100 mrem /h Fifteen minutes earlier the reading was 200 mrem /hr with the meter in the same position. HCW long must you walt until the radiation level drops to 10 mrem /hr?
SHOW ALL WOR (2.0)
QUESTION G.03 (1.5)
In accordance with the Required Procedures for Radiation Protection Indicate whether the f ollowing are TRUE or FALS Liquids are NOT 111cwed to be p1 aced into a collection container designated for solid wast (0,5)
l It IS oermissible to pl ace a small bottle containing low level radioactive water into a
' Liquid Radioactive Waste" collection containe (0.5) It IS permissible to dispose of a 3 pound slightiv rndloactive piece of metal in a collection container designated for solid wast (0.T)
(.**** CATEGORY G CCt4T!t4UED CN t4 EXT PAGE *****)
. _ . _____________ _ ______________
-
.
I PADIATION CCNTROL AND TAFETY
.
QUESTION G.04 (2.0)
A por tabl e r adi ation moni tor indicates a reading od 60 mr/hr at a distance of 10 feet from what could be *
considered a radioactive point source (gamma enmitter).
You are required to work on a valve located 5 feet from t.)e sourc You estimate the Job will take 10 minute WHAT dose would you expect to receive if you worked on the valve for 10 minutes? SHOW ALL WOR (2.0)
OUESTION G.05 (2.0)
Consider the Core Purge Monito WHAT type of de tec tor is used in this monitor? (0.5) Describe the automatic actions which occur if the (1.5)
"High Radiation Core Purge" al arm is actuate OUESTION G.06 (1.0)
An operator enters an area that is posted as a "radi ation area" (as defined in 10 CFR 20). He performs a job that takes him 40 minutes t o c omp l e t e . WHAT is the MAXIMUt1 dose he could expect to receive? <!.0)
OUEST!ON G.07 (2.0)
According to 10CFR 20, an individual in a restricted ar e a may be a1104ed to receive a whole body dose of radiation greater than 1.25 Rems per calendar quarter under certain condition Name the condition (2.0)
OUESTION G.08 (2.0)
.
Give the f oll owing inf ormati on concerni ng N-16 HOW is N-16 produced? (0.5) WHAT is the primary ha:ard associated with the oroduction of N-16? (0.5) !s N-16 a radi ation problem when the reactor is shutdown? Eriefly explai (1.0)
(***** END OF EXAM +++++)
^
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E = ac KE = 1/2 av a=(Vf-V,)/t A = 1M A=Ae"*g PE een :
v f = V, + at w = e/t A = sn2/t1/2 = 0.493/t1/2 y .yg -
- 1/2e# = ((tin)(g)]
-
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.
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CA, = 5/(1 - K,ffx)
l SUR = 25e/ t' + ( s - o )T G j(1 - K,ff3) = CR2 (I ~ eff 2) '
- i
'
T = (s*/s) + C(s - e)/le] , M = 1/(1 - K,g) = CRj /G, !
- 7 = s/(e - s) .
M = (1 - Kgf,)/(1 - Kgf 3) '
] T = (s - s)/(1s) SDM = (1 - K g )/Kgf
/ t' = 10-5 ,,e,f,q, i
e = (K, gf-1)/Xdf"'"#f*df ,
'
-
_
T = 0.1 seconds"I
. = C(s*/(T Kgf)]+Cigf(1+iT)) / l
'
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, P = (s4V)/(3 x 1010) Id jj hd2
- 2 *
l z = en '
R/hr .= (0.5 CE)/d (meters)
l R/hr = 8 C2/d2 (feet) f
Water Parameters Miscellaneous conversions !
.
'
!
1 gal. = 8.345 tes.- *
I curie = 3.7 x' 1010 des 1ga[.=3.75litars 1 kg = 2.21 Its l 1 ft" = 7.44 ga I hp = 2.54 x 103 stu/hr
~
Density = 62.4 Ing/ft3 1 as = 3.41 x 106 stu/hr ,
- Gensity = 1 gn/cW -
,
lin = 2.54 cm ;
Heat of vaporization = 970 8tu/les *F = 9/5'C + 32 Heat of fusion = 144 Stu/lbe 'C=5/9(*F-32)
._ , 1 Ana.= 14.7 pst = 29.9 in H . . _ - _ _ - - - - _ - _ - - .- - _
i em = nn *-1w
_ - _ . . - _ - . - - - . - . - -
Dr tee ltl Ansdotto
- TAM / PRINCIPLES OF REACTOP OPERATION
- ANSWERS -- MITRII - 88/9/12 - ROBINSON, ANSWER A.01 (2.5) EE2 = 1-(Re4fl> =10 CR1 1-(Keff2) (0.75)
delta K/K = 1-(Keff1) .04; (Keff1) = 0.962 (Kefft) (0.5)
1 .962 = 101 Keff2 = .9962 1-(Keff2) (0.75) TRUE (0.5)
REFERENCE Reacto? Physics Notes: Reactor Startup and Reactor Sub-cri tical ML1 tiplication p. ~
.
ANSWER A.02 (2.0)
Del ayed neu trons f rom f i ssi on f ragmen t decay G. e/
(i.e. Br-87 with a 55 second half-life). (1.?")
Photoneu trons f rom gammas (f rom fission f ragment decay)
which interact with deuterium (in the heavy water f.#
reflector). (ETPS)
N utr; : ' ;m ngte.;;ec ;ogrce, polca;; , r.d be.r!u (675$
(CAf W': ;;sice ii .v , L.,,, , ,myge d y, ;, i..lg-n!'!: rt, If so, adjust point value to 1.0 each f or above answers.)
NOTE: Information in parenthesis NOT required to receive full, credit for answe REFERENCE Reactor Physics Notes: Reactor Startup and Reactor Subcritical Multiplication p. 7 and Reactor Kinetics p. 1 ANSWER
. - - - - -
A.03 (2.0)
a. FALSE (0.5)
b. FALSE (0.5)
c. TRUE (0.5)
d. TRUE
'
(0.5)
REFERENCE Reactor Systems Manual 1 Reactor Physics Notes Reactivity Feedback and Measurement of a Xenon Transient p. 24, 30, 3 !
- ,,
l l
.
I A PRINCIPLES OF PEACTOR OPERATION ANSWERS -- MITRII - 88/9/12 - ROBINSON, ;
ANSWER A.04 (2.0)
,
P(t) = P(o) exp (t/ tau) = 100 watts exp (480/60) (0.5)
P(t) = 298 kw (0.5)
ye s '* ^^ - ^
j We3 increase in mcderator temperature -- ive- l
>+++tiw ;j .4 es * ***AI* (1.0) y a 41 e e on e r ***4 . . eno6*y ar +t . . ;; . ;V 5 e s'
+ *< r * * A* *f* * *7k * i (Note: The temperature reactivity feedback effect becomes apparent at approximately 100 kw, SOP PM 2.3 p. 3 .) s * " * 78'3 '#<***"*
REFERENCE Reactor Physics Notes: Reactor Kinetics p. 4 Reactor Systems Manual 1 ANSWER A.0" (2.0)
The case when K-effective is 0.995 will take longer to
- reach equilibriu (0.5) l i / !
- The nearer K-effect is to one, the longer it takes to reach
'
a new steady state, because of the increased number of generations which exist with the increased populatio (1.5)
REFERENCE
"
Reactor Physics Notes: Reactor Startup and Reactor Suberi tical Multiplication p. 8, 9, 10.
,
,
ANSWER A.06 (2.0) :
P l
,
Period = = 35 sec = 50.5 sec (0.5) :
.693 .693 Reactivity = beta /(1 + lambda x tau). (0.5) .
= .00784/(1 + .08 x 50.5) (0.5) j
= .00156 del ta K/K (0.5)
or 0.198 beta REFERENCE '
Reactor Physics Notes Reactor Kinetics and Control Rod
. Calibration by Reactor Period Measurement p. 3, 4, 14, 1 l .
!
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. - - - _-.
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l e PRINCIPLES OF REACTOR OPERATICt1
-
ANSWERS -- MITRII -
88/9/12 - ROBINSON, ANSWER A.07 (2.0)
, TRUE (0.5)
J FALSE (0.5)
' FALSE (0.5) TRUE (0.5)
t RERFERENCE Reactor System Manual 1 .a i
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l
, FEATURES OF FACILITY DESIGN
. HNSWERS -- MITR 11 - 88/9/12 - ROBINSO4, ANSWER B.01 (2.5)
Sea enclosed figure (3.3-1)
REFERENCE Reactor Systems Manual 3.7 and Fig. 3.3-1 Answer B.02 (2.0) Moisture entrained with the air would degrade the heavy water (D20 dilution). (0.5)
Nitrous oxide formation from the presence of air in high radiation fields would cause corrosio (0.5) The temperature of the middle of the recombiner must exceed a niinimum required value (50 degrees C.) . (0.5)
The f l ow r a t e through the recombiner must be between certain flow rates (1.5 and 8.0 cfm.) . (0.5)
Aho, s oo r st n e ht o * *.< * $ n o t * *r oe d f radr/t Ar**/ N W'* "
REFERENCE /l, deswp,< # ,4 o',g s p f c , , d e/ 0, /o, ,(, m,w e rek Reac tor Systems Manual 3.16
.
ANSWER B.03 (2.0)
I Normal shu tdown cool i ng i s prov i ded by air auxiliary pump l (MM-2) and the cleanup loop heat exchanger (HE-2). (1.0)
Maximum flow can be obtained by bypassing the ion column and the inlet and outlet filter (1.0).
REFERENCE Reactor Systems Manual 3.4 i ANSWER B.04 (2.0) If the ventilation should be lost, the intake damper will close, thereby, forcing all air within the build-ing to flow past the pienium monitor prior to being
-
discharge (1.0) A manually operated exhaust control damper (located in the stack base) is used to throttle the overall flow of air through the ventilation syste (0.5)
The opening of the damper is adjusted to maintain the building di f f erenti al pressure between the intake and l the exhaus (0.5)
REFERENCE Reactor Systems Manual 8.12, 8.16
, .
.
_ - _ ____-______ - _ _ _ _ _ _ _ _ _ _-
. _ _ _ _ - _ _
?
- >
. FEATURES OF FACILITY DESIQtj l ANSWERS -- MITR !! - 88/9/12 - ROBINSON, ,
ANSWER B.05 (1.5) A plug is placed in the por (0.5) Gas seals are made by bolting a ring against the ,
"
aluminum flange of the line (0.5) A gasket cover i t; bol ted over the beam port's openin (0.5) [
'
REFERENCE Reactor Systems Manual ,
ANSWER 9.06 (2.0) Fuel element positions in each ring are numbered >
sequentially in the clockwise. direction from the regulating rod positio (1.0) The elements are axially symmetric so that they can be inverted in order to equalize any peaking in axial burnu (1.0)
REFERENCE Reactor Systems Manua' 1.4, i r
!
'
ANSWER B.07 (2.0)
, gem (0.5) i kw (0.5) ; degrees 0 -
(0.5) l inches below the overflow pipe (0.5) L (CAF for actural height above core) l I
REFERENCE !
Technical Specifications p. 2-5 j r
.
h I
f
.
.
. _ - _ _ _ _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _____
' GENERAL OPERATING CHARACTERIST1[1 ANSWERS - MITRI! - 88/9/12 - ROBINSON, .
ANSWER C.01 (2.0)
The amount of negative reactivity added is dependent on the position of the shim blade ban (1.0)
This effect can be considered as being due to the shadowing influence that the blade bank inserts on the reflecto (1.0)
REFERENCE
' Reactor Systems Manual p. 1 ANSWER C.02 (2.0) An increase in the light Nater temperature will insert
negative reactivity by causing the hardening in the neu tron spec trun <1.0) An increase in the heavy water reflector temper-ature will insert negative reactivity by all owi ng more neutron leakag (1.0)
REFERENCE Reactor Systems Manual p. 1 ANSWER C.03 (1.5) FALSE (0.5) TRUE (0.5) TRUE (0.5)
REFERENCE Operating Procedure Checkilst PM 3.1. p. 13 ANSWER C.04 (2.0) OUT (0.5) IN (0.5) (# (0.5) NO EFFECT (0.5)
REFERENCE Reactor Systems Manual p. 10.10
-- _ _ _ _ _ _ _ _ _ _ _
. GENERAL OPERATING CHARACTER!ST!Ci
.
ANSWERS - MITR11 - 88/9/12 - ROBif 4SO4, ANSWER C.05 (0.0) The full-in position for the regulatory rod is six (1.0)
inches above the bottom of the fuel element Once the regulating rod is withdrawn any appreciable amount, it is heavily shadowed by the adjacent shim (1.0)
blade REFERENCE Reactor Systems Manual p. 1 ANSWER C.06 (2.5) The delta K due to temperature change or the change in average temperature and temperature coefficien (0.5)
The delta K due to the addi tional s anpl e . (0.5) The delta K due to burnup or MWH and delta K per MW (0.5)
The previous critical rod position (0.5)
, Rod worth curve (0.5)
REFERENCES Operating Procedure Checklist PM 3.1. p. 13 ANSWER C.07 (1.5) Approximately 2 beta of excess reactivit (0.5) In order to be able to override the xenon shutdown (1.0)
transien REFERENCE Reactor Systems "anual p. 1 ANSWER C.08 (1.0)
n. TRUE (0.5)
b. TRUE (0.5)
REFERENCE Reactor Systems Manual p. 1 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
, _ _ _ _ _ _ _ _ _ _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
- !
- INSTRLNENTS 4.ND CONTROLS ANSWERS - MITR!! - 88/9/12 - ROBINSON, ANSWER D.01 (2.5)
/ A neutron entering the chamber causes a uranium atom l (in the uranium oxide coating) to fissio (0.75) l The resulting fission products create a large neg- t
'
ative ionization pulse in the counting ga (0.75) A pulse height selector is used to distinguish the large negative pulses created by neutron-induced v fissions from the smaller pulse produced by the gamma rays and alpha particle (1.0)
i REFERENCES i Reactor Systems Manual p. ,
r l
ANSWER D.02 (2.5) ,
The automatic control circui t can no longer Keep reactor (
p owe r a t the set power level and power would start to l increas (0.5) !
-
The automatic run-down circuit causes a visual alar (0.5) t After 30 seconds delay, the circuit transfers reactor l control to manual mod (0.75) ;
The circuit then drives in the selected shim ro (0.75) l l
REFERENCE Reactor Systems Manual p. l
!
t i
ANSWER D.03 (2.5) I i must be satisfied (0.5) !
I need not be satisfied (0.5) ' must be satisfied (0.5) [
i must be satisfied (0.5) ;
, neednotbesatisfied$,ue**#")) (0.5)
muse he r.4e /ved & A# / **at4 *# l
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(Acceptable answer therefore i s a, c, and d.)
ed e t REFERENCE ;
Reactor Systems Manual p. 4.1 and (
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. INSTRUMENTS AND CONTROLS
- .
ANSWERS - MITRi! - 88/9/12 - ROE!NSO4, ANSWER D.04 (2.0) To maintain the shim blade bank programmed at a uniform height during the final approach to criticalit <!.0) To establish a level, be l ow the critical position, to which the shim blades may be indiuldually wi thdrawn in one ste (1.0)
- REFERENCE Reactor Systems Manual .3 ANSWER D.05 (1.0)
Depressing the "all-absorbers- in" pushbutton will give (1.0)
the scram klarm but will not scram the reacto REFERENCE Reactor Systems Manual p. ANSWER D.06 (2.5) The graphite reflector has a large heat capacity and i s sl ow to attain an equilibrium temperature (0.7)
distributio Pr imary fl ow r ate , core temp. rise, and heat capacity. (0.6)
Heavy water reflector flow rate, temp. rise, and heat capacit (0.6)
Shield coolant flow rate, temn. rise, and heat capacity (0.6)
.
REFERENCE Reactor Systems Manual .4
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_ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - _ ____
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. INSTRtriENTS AND CONTROM ANSWERS - MITRI! ! S8/9/12 - ROBINSON, '
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t ANSWER D.07 (1.5)
Two concentric cylindrical electrodes, measures the j resistivity of the wate (0,5)
l A potential voltage applied across the cell produces a 7
current that is inversely proportional to resistivit (0.5)
f Resistivity varies inversely with conductivit (0.5)
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(Also acceptable is - conductivity is directly proportional i
to current flowing through the cells.)
i REFERENCES Reactor Systems Manual .1 l i
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. SAFETY AND EMERGENCY SYSTEMS
, ANSWERS - MITRll - 88/U12 - ROBINSON, ANSWER E.01 (2.5) WILL NOT BE SUPPLIED (0.5) WILL BE SUPPLIED (0.5) WILL NOT BE SUPPLIED (0.5) WILL BE SUPPLIED (0.5) WILL BE SUPPLIED (0.5)
REFERENCE Reactor Systems Manual .34 ANSWER E.02 (1.5) FALSE (0.5) FALSE (0.5) TRUE (0.5)
REFERENCE Reactor Systems Manual .23 ANSWER E.03 (2.5) The flow goes up through the core and down through the flow shrcad-check valves (by natural circulation). (1.0)
qa rns
- Heat lost to ambient (0.5)
f i Heat lost to the reflector Yank (0.5)
il Heat lost to the off-gas system (0.5)
REFERENCE Reactor Systems Manual .5 l
_ _ _ _ _ _
- _ _ _ _ _ _ _ _ _ -
. SACETY AND EMEoGEPCY ?YeTEM?
AN9JERS - MITR!! -
88/9/12 - ROBINSCN. G.
i AilSWER E.04 (2.5) Both emplov differen+,ial pressure transducers that measure the difference between static pressure in the air gap area (above the outlet plenum) and the pressure developed by a reference leg that extends into the core tank to a point immediately above the (1.5)
top of the fue ML-3A is electrically-driven (piezo- electric d i f f e .* * n t i a l pressure transducer) and is supplied (0.o) w by emergency pcwe ML-3B is pneumatically-driven (transmitter) (0.5)
and is supplied by instrument ai REFERENCE Reactor Systems Manual .8 ANSWER E.05 (2.0)
A period scram is fast acting, that is it is coupled directly to the magnet-current amplifiers and upon a preset se.r am s i gn al interrupts the current to the (1.0)
magnets of the six shim blade A low primary coolant fl ow c aused scram is initiated by a relay which opens the withdraw circuit, thereby, (1.0)
causing the current to the magnets to be cut of REFERENCE Reactor Systems Manual .8
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. SAFETY AND EMERGENCY SYSTEMS ANSWERS - MITR11 - 88/9/12 - ROBINSON, ANSWER E.06 (1.5) Secures the ventilation system (0.5) Seals the containment shell (0.5) Dumps the top part of the henvy water reflector (10,5)
REFERENCE Reactor Systems Manual p. ANSWER E.07 (1.5) second period (0.5) gpm (0.5)
, .S& gpm (0.5)
REFERENCE Reactor Systemn Nanual r. 9.9 i
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. STANDARD .44D EMERGENCY OPERATING PROCEDUPES ANSWERS - MITR11 - 88/0/12 - ROBINSO4, .
ANSWER F.01 (2.5) Reactor Superintendent (0.34)
Duty Shift Supervisor (0.33)
The Electronics Supervisor (0.33)
(or designated alternates) Two responsible people must check the Jumper after (0.5)
installatio The Jumper must be tagged for identificatio /0.5)
A record of the authorizer's initials must be recorded on the bypass log thee (0.5)
REFERENCE Administrative Procedure PM 1.9 ANSWER F.02 (2.0) .
High Primary Cool ant Conduc t ivi ty (alarm) (1.0)
Increase in results of the weekly analysis of the primary coolan (1.0)
REFERENCE Abnormal Operating Procedure PM 5. ANSWER 5.03 (2.5) MINOR SCRAM (0.5) NO SHUTDOWN REQUIRED (0.5) MINOR SCRAM ,geswas o (0.5) SHW4GOW>+-9V-MM s e * *r## * , (0.5) NO SHUTDOWN REQUIRED (0.5)
REFERENCE Abnormal Operating Procedures PM 5.1.4, PM 5.2.1, Pm 5. PM 5.4.3, PM 5. _ ______________
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- STANDARD AND EMERGENCY OPERATING RROCEDURES ANSWERS - MITRI! - 88/9/12 - ROBINSON, ANSWER F.04 (2.0)
Any four (4) of the f oll owing: Any change in reactivity Any decrease in primary cool ant fl ow Any increase in the core purge Any increase in primary conductivity readings Any increase in the core outlet temperature Any increase in the core del ta temperature
(Note Each response is worth 0.b points.)
REl'ERENCE Abnormal Operating Procedure PM 5.2.11 ANSWER F.05 (2.0)
Xenon (0.5)
Fuel Burnup (0.5)
,
Sample changes made in operation (0.5)
Changes in experiments during operation (0.5)
]
REFERENCE Technical Specifications p. 3-33 ANSWER F.06 (2.0)
Scram the reacto (0.5)
Turn on the '00 NOT ENTER" sign for the back personnel loc (0.5)
Remove the reactor KEYS and (0.5)
Console l og (0.5)
t REFERENCE Abnormal Operating Procedure PM 5.7.8
{ ANSWER F.07 (1.5) TRUE (0.5)
- TRUE (0.5)
' FALSE (0.5)
REFERENCE Standard Operating Procedure PM p. 2 and 3
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- RADI AT10tJ CONTROL #4D 9AFETY ANSWERS - MITR!! - 88/9/12 - ROBINSCti, ANSWER G.01 (1.5)
NO (0.5)
'e unit Rem considers the different effect Rem is a i biological uni t , thus different radiation causing the same dose in Rem should have the same effec (1.0)
REFERENCE 10 CFR 20 RPO Notes and Memos c ANSWER G.02 (2.0)
A(t) = A(o) e ** - Ikmbda t (0.5)
t = 15 minutes
A(t) / A(o) = 100 / 200 = (0.5) ;
lambda = -(In 0.5) / 15 min = .046 / min (0.5)
t = -(in 10/100) / (0.046/ min) = 50 minutes (0.5) ,
REFERENCE Nuclear Reactor Engineering, Glasstone and Sesonske p. 31
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ANSWER G.03 (1.5) TRUE (0.5)
' FALCE (0.5) TRUE (0.5)
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REFERENCE
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MIT Required Procedures for Radiation Protection p. 20 and 21
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' RADIATION CONTROL AND SAcETY
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ANSWERS - MITRi! - 88,'9/21 - ROBINSON, ANSWER G.04 (2.0)
(0.5)
D1 X R1 X R1 = 02 X R2 X R2 (1.0)
D2 = (60 mr/hr) v to 4t v 10 4t = 240 mr/hr 5ft x 5ft (0.5)
Dose = (240 me/hriv 10 min = 40 mr (60 min /hr)
REFERENCE p. 524 Nuclear Reactor Engineering, Glasstone and Sesonske ANSWER O.05 (2.0)
(0.5) G-M "Pancake" detector
,,6 s .d w two. O**la' * I tf7=93 automatically closes , ,/, m a as M =, ^w) (0.5)
(0.5)
MU-64 au t omat i c al l y closes (0.5)
Core purge blower is turned oH
. REFERENCE Reactor Systems Manuti p. 7.12 ANSWER G.06 (1.0)
(0.5)
Max'imum dose rate is 100 mr/hr (0.5)
(40 min /60 min? x 100 mr = 66.7 mr REFERENCE IV CFR 20.203
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p
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. RADIATION CONTROL AND SAFETY ANSWERS - MITR11 - 88/9/21 - ROBINSON, ANSWER G.07 (2.0) He/she does not exceed 3 Rem per quarte (0.5)
, His/her radiation histroy is known and recorded on the proper form (Form 4). (0,5) The dose received when added to his/her radiation history does not exceed 5(N-18) Rems where N = the person's age at his/her birthda (1.0)
REFERENCE 10 CFR 20.101 ANSWER G.08 (2.0) N-16 comes from 0-16 via a(n.p) reactio (0.5) Its primary hazard is the high energy gamma ray given off (0.5) NO, (0.25)
because of its short half life (7 see) (0.75)
REFERENCE Nuclear Reactor Engineering, Glasstone and Sesonske p. 402
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ATTACHMENT 2
. . U. S. NUCLEAR REGULATORY COMMISSION SENIOR REACTOR OPERATOR LICENSE EXAMINATION
. FACILITY: MIT REACTOR TYPE: RESEARCH ;
DATE ADMINSTERED: 88/09/12 EXAMINER: YACHIMIAK. ,
CANDIDATE CLO A_
INSTRUCTIONS TO CANDIDATE:
Use separate paper for the answers. Write answers on one sice onl Staple question sheet on top of the answer sheet Points for each question are indicated in parentheses after the questio The passing grade requires at least 70% in each category. Examination papers will be picked up six (6) hours after the examination start % OF CATEGORY % OF CANDIDATE'S CATEGORY VALUE TOTAL SCORE VALUE CATEGORY 19.6 0 20.00- 20.00 REACTOR THE0kY I4,So
_-20.00 20.00 RADIOACTIVE MATERIALS HANDLING DISPCSAL AND HAZARDS A 20.00 20.00 SPECIFIC OPERATING CHARACTERISTICS ,
-4HH+ .00 FUEL HANDLING AND CORE PARAMETERS h 20.00 ADMINISTRATIVE PROCEDURE CONDITIONS AND LIMITATIONS i 9 LGe-e- % Totals
+
Final Grade All work done on this examination is my ow I have neither given nor received ai O C 'p14C b G(M Candidate's Signature
/u b 44 d?1 gagg conndo .
. _ __ __ _ ________ _
, NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS During the administration of this examination the following rules apply:
' Cheating on the examination means an automatic denial of your application and could result in more severe penaltie . Restroom trips are to be limited and only one candidate at a time may leav You must avoid all contacts with anyone outside the examination room to avoid even the appearance or possibility of cheatin . Use black ink or dark pencil only to facilitate legible reproduction . Print your name in the blank provided on the cover sheet of the examinatio Fill in the date on the cover sheet of the examination (if necessary). Use only the paper provided for answer . Print your name in the upper right-hand corner of the first page of each section of the answer shee . Consecutively number each answer sheet, write "End of Category __" as appropriate, start each category on a new page, write only on one side of the paper, and write "Last Page" on the last answer shee . Number each answer as to category and number, for example, 1.4. . Skip at least three lines between each answe . Separate answer sheets from pad and place finished answer sheets face down on your desk or tabl . Use abbreviations only if they are commonly used in facility literatur . 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 require . Show all calculations, methods, or assumptions used to obtain an answer to mathematical problems whether indicated in the question or not, i 15. Partial credit may be given. Therefore, ANSWER ALL PARTS OF THE QU'"* ION AND DO NOT LEAVE ANY ANSWER BLAN . .. cts of the examination are not clear as to intent, ask questions of the examiner onl . You must sign the statement on the cover sheet that $adicates that the work is your own and you have not received or been given assistance in completing the examination. This must be done after the examination has been complete _ _ _ - - _ _ _ _ _ _ _ _ - _ _ _ _ _____ - _ _____ __ _ - _ - __ _ _ - _ _ _ _ _
18. When you co:ploto your excoination, you oholl: [
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a. Assemble your examination as follows:
,
(1) Erem questions on to (2) Exam aids - figures, tables, 42t l
(3) Answer pages including figures which are part of the answer, i l
b. Turn in your copy of the examination and all pages used to answer [
the examination question !
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c. Turn in all scrap paper and the balance of the paper that you did :
not use for answering the questions, j
d. Leave the examination area, as defined by the examiner. If after l leaving, you are found in this area while the examination is still t in progress, your license may be denied or revoke ;
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(l.S0) }
QUESTION H.01 * 2. 0 ^ )- !
a. WHY is the value of Beta-effective greater than the value of Beta? '
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L. nni does the value of Bewa wifwuii.. d;;;n .. during core 11xei ( 0. 50 ' -
c. WHAT is the source of the neutrons that cause the characteristic i-80 second period on a reactor scran? (0.50) l ,
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QUESTION H.02 (2.50)
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Given that the reactor is suberitical with a Keff of 0.9875 and a Start-Up channel reading 2000 CPS:
a. WHAT would Keff be after a reactivity addition causee the count rate to increase to 4000 CPS 7 SHOW ALL WOR b. Would the reactor be Suberitical. Critical, or Supercritical if 1.59 Beta was added to the 0.9875 Keff core? SHOW ALL WORK, (***** CATEGORY H CONTINUED ON NEXT PAGE *****)
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QUESTION H.03 (2.75)
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Assume the reactor is on a stable 40-second period, a. HOW long (in minutes) will it take to change power level TWO (2)
decades? SHOW ALL WOR (1.75)
b. HOW nuch reactivity (in Hillibeta) has been inserted into the reactor ir order to place it on this stable period? Assume the reactor was just '.
critical prior to this reactivity insertion. SHOW ALL WOR (l.00)
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! QUESTION H 04 (1.50)
a. HOW (Increase, Decrease, No Change) does a DECREASE in reactor power affect the Capture Cross Section of U-238 at its resonance energies?
(0.50)
b. WHAT are TWO (2) reasons WHY a neutron whose energy is slightly above the upper limit of a U-238 resonance capture energy will still have a high probability for capture by a U-238 atom? (1.00)
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QUESTION H.05 (4.00)
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a. Briefly state the Production AND Removal mechanisms for Xe-135 AND Sm-149. Include applicable elements and isotope (3.00)
b. HOW (Increase. Decrease, No Change) would Xe-135 affect the the reactor's Actual Shutdown Margin TWO (2) hours after a reactor trip frot continuous power operation at > 100 kW7 (0.50)
c. HOW long does it take Xe-135 to build into a core that has been shutdour for refueling? Assume the reactor is run at rated powe (0.50)
(***** CATEGORY H CONTINUED ON NEXT PAGE *****)
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QUESTI0ti H.06 (2.00)
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a. WHY does the moderator temperature coefficient become MOPE negative as the moderator heats up?
b. WHAT are the TWO (2) reasons for the negative reactivity effect associated with an ItiCREASE in moderator temperature?
(***** CATEGORY H C0tiTItIUED ON NEXT PAGE *****)
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QUESTION H.07 (2.00)
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a, WHf is D20 (heavy water) used in the MITR-II as a reflector instead of H207 b. HOW does the D20 reflector produce source neutrons when the reactor is subcritical?
(***** CATEGORY H CONTINUED ON HEXT PAGE *****)
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QUESTION H.08 (1.25)
Calculate reactor power (in MW) given the following operating conditions:
Reactor Inlet Temperature -
110 Reactor Outlet Temperature -
130 Reactor Primary Coolant Flow Rate - 1800 gpm (***** CATEGORY H CONTINUED ON NEXT PAGE *****)
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QUESTION H 09 (2.00)
.
Answer the following questions regarding the design of the MITR-II fuel elements:
a. WHY must the fuel have a minimum cladding thickness of 0.008 inchen?
b. HOW would a thicker clad affect the ability of a fuel element to transfer heat during power operations?
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__ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ . RANI 0 ACTIVE MATRnIALE HANDLING DISPOSAL Peso 11 o AND HAZARDS ,
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, QUESTION I.01 (2.50) ;
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a. WHAT THREE (3) conditions would individually activate the "Waste Tanks" alarm on the control room scram panel? (1.50) i ;
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b. WHERE would water from the Waste Tanks vent to if both tanks were overfilled? (0.501 :
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, Waste Tanks to the sewer system? (0.50)
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_
QUESTION I.02 l?.00)-
. rWO O)
WHAT are the PHRet 4-H actions AND the ONE (1) control room indication which are automatically initiated on a steadily increasing sump level in the equipment room?
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l QUESTION I.03' (1.50)
O In accordance with operating procedure 3.12.2, "Procedure for Cell Entry," t a. WHAT preventative action must be taken to protect persona from exposure to high radiation leveld whenever the LEFT cell is not on use? (1.00) ;
r b. WHOSE approval is required prior to entry into the RIGHT cell? (0.50) [.
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QUESTION I.04 (2.50)
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Given a gamma source which has a measured dose rate of 100 mR/Hr at 10 feet from the source:
a. Calculate how much time must pass (in minutes) until the dose rate at 1 foot will be 100 mR/H Assume a source half-life of 15 minutes. (1.50)
b. Instead of waiting for the source to decay further, calculate HOW MUCH lead shielding (in centimeters) would have to be used in order to lower the dose rate from 100 mR/Hr to 1 mR/Hr at 1 foot. Assume a mass attenuation coefficient of 0.189 ?._/m 2) and a density of 11.34 (sm/cm3), a (1.00)
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QUESTION I.05 (3.00)
An irradiated component is surveyed with a portable instrument. The open window indication is 2.00 R/Hr while the closed window reading is 1.50 R/Hr both at a distance of 18 inche a. WHAT is the Beta dose rate at 18 inches from the component?
b. WHAT would be the maximum time that you could remain at the survey distance without exceeding your 10CFR20 quarterly WHOLE BODY limit?
Assume you are without a Form NRC-4 and have no current exposure this quarte Also, assume that you are wearing the appropriate protective clothing / articles, c. WHAT would your 10 CFR 20 limit for quarterly AND lifetime dose be with a completed Form NRC-47
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O QUESTION I.06 (1.50)
WHAT are THREE (3) gases that are removed by the Core Purge (Off-Gas)
System?
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QUESTION I.07 '(2.00)
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a. HOW do the gamma-sensitive scintillation detectors detect Tritium-leakage into the Secondary Water System from the D20 reflector heat exchanger?
b. WHY must blowdown of the cooling tower basins be secured whenever the reactor.is not operating?
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QUESTION I.08 (3.00)
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. In order to receive' radioactive material ordered for delivery to the NRL, a member of the operations staff must possess WHAT TWO-(2)
qualifications? (1.00)
b. WHAT FOUR (4) actions need to be taken by the individual receiving a radioactive material package? (2.00)
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QUESTION I.09 (2.00)
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a. WHAT are the TWO (2) reasons for which an individual may be authorized to incur. radiation exposures in excess of the 10 CFR 20 limits?
b. If time permits, WHAT TWO (2) people should make the above authoriza-tions?
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.7 . SPECIFIC OPERATING CHARACTERISTICS Pego 20-
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QUESTION J.01 (2.25) , ,
Describe the operation of the pneumatic tube system including both the i rabbit insertion and ejection processes. Identify ALL major components in your description.
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QUESTION J.02 (1.50)
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a'. WHAT are TWO (2) reasons for having a CO2 purge maintained to the-s water-cooled, vertical sample thimbles? (1.00)
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, ;for sample irradiation? (0.50)
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QUESTION J.03 (2.50)
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a. Explain the-operation of the Anti-Syphon valves (both open and closed positions), specifically addressing HOW the valve would prevent the complete drainage of the core tank on a coolant pipe brea b. Explain the operation of the convection valves during both normal and loss of coolant flow condition Include in your explanation a decription of.the coolant flowpaths involve i
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QUESTION J.04 (2.50)
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QUESTION J.05 (2.75)
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a. WHY is 125 volt D.C. storage battrery power needed to prevent simultan-eous closurs Of time two (2) main 13.8 KV circuit breakers? (0.75)
-b. Describe the operation of the ersergency electrical power distribution system, including the 5 KVA motor-generator (M/G) set, during both the ,
loss and susequent reatciration of normal powe (2.00)
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QUESTION J.06 (2.00)
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WHAT FOUR (4) actions occur when a major scram pushbutton is depressed?
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QUESTIGS J.07 (1.50)
- a. When operating at full power. WHAT could result if secondary system temperature dropped to less than 6 degrees (0.50)
B. WHAT are.TWO (2) actions that could be taken to reduce the rate of secondary system heat removal WITHOUT decreasing reactor power? (1.00)
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QUESTION J.08 (1.00)-
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.. During a reactor startup. WHY'is reactor power held constant for FIVE.(5)
minutes after each_11.M11 increase:in power level?
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QUESTION J.09
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WHAT are the FOUR (4) requirements imposed by the "automatic-control-
-permissive" circuit which must be met before the reactor can-be shifted to automati'c control?
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QUESTIOli J.10 (2.00)
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WHAT are 4he FOUR (4) functions of the Cleanup System?
(***** EllD nF CATEGORY J *****)
-- _ _ __ -__ _ _ ______ -_ _ ____________ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - - - _ _ _ _ . FUEL HANDLING AND CORE PARAMETERS Pago 30
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QUESTION K.01 (2.00)
During performance of a spent fuel transfer:
a. WHY is the inner door of the main personnel lock left open? (0.50',
b. WHAT are TWO (2) locations in the core tank from which fuel elements ma) L be transferred to the transfer cask? (1.00 ;
c. WHY is the reflector dumped prior to fuel movement? (0.50~
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QUESTIOli K.02 (3.50)
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a. Describe the construction of the storage racks currently installed in the spent fuel storage poo Include in your description the rack's material composition AtID the reason for the material's us (2.50)
b. WHAT are TWO (2) reasons for using high purity deionized water in the spent fuel storage pool? (1.00)
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QUESTION K.03 (1.50)
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a. HOW much time must elapse between a reactor shutdown and the removal of fuel from the core if the reactor had previously operated at power levels in excess of 100 KW7 (0.50)
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b. WHAT is the Technical Specification basis for the above time constraint?
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(1.00)
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QUESTI0ti K.04 (1.00)
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Bolt Cutters are required for the removal of WHAT TWO (2) reactor reactivity control components?
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QUESTION K.05 (2.00)
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In accordance with PM-3.3.2, "Spent-Fuel Removal."
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a. WHAT precaution must be taken by individuals whenever they are Performing physical work activities on the reactor top with the reactor top shield lid removed? ;
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b. WHAT action must be performed on Nuclear Instrumentation-Safety Channels '
5 and 6 before a full power startup may be initiated? ;
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QUESTION K.06 (3.00)
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Give the basis for each of the following Technical Specifications:
r. The reactivity worth of the regulating rod connected to the automatic control system is less than 1.8 % delta k/ b. The maximum controlled reactivity addition rate is no more than:
-4 5 X 10 delta k/k/second.
I c. The reactivity worth of the D20 reflector dump is greater than the
- reactivity worth of the most reactive shim blade.
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QUESTION K.07 (2.00)
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WHAT are FOUR (4) conditions that could actuate a Spent Fuel Storage Pool (SFSP) alarm?
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GUESTION K.08 (1.50)
. i In accordance with PM-1.15 "Refueling "
a. WHAT TWO (2) individuals must sign the Fuel Loading Verification record
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and Fuel Loading Permission Form? (1.00)
b.. Prior to exceeding WHAT power level must the Fuel Loading Verification ;
record be signed by the two above individuals? (0.50) i I
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QUESTION K.09 6 -
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a. WHAT Fuel Element Assembly design characteristic enables the fuel to achieve a more complete burnup? (0.50) '
r b. For a Fuel Element Assembly which has b a 1s Jud witn an increased I amount of U-235, explain HO tion of a Burnable Poison limits '
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element till allows for an increase in the element's overall
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c. HOW does the loading of Hafnium, fixed, neutron-absorber plates on the absorber spider assembly affect the core's nuclear flux / power? t List TWO (2) effect (1.50) r i
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. _ - ADMINISTRATIVE PROCEDURES. CONDITIONS Pega 39
, AND LIMITATIONS
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QUESTION L.0 (2.50)
a. WHAT are THREE (3) reasons why all positions in the core tank must be filled and secured with either a fuel element or another approved unit before operating at full power is allowed per Technical Specifications?
(1.50)
b. In accordance with Technical Specifications . WHY are at least FIVE (5)
operable shim blades required to be within 2.0 inches of a banked (average shim blade height) position when the reactor is at power levels of greater than 100 kW7 (1.00)
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QUESTION L.02 (2.50)
a. WHAT THREE (3) reactor parameters have indication which is required to be supplied by emergency power whenever the reactor is operating? (1.50)
b. WHAT are the TWO (2) reasons that the use of emergency power is probably not necessary for the MITR-II? (1.00)
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QUESTION L.03 (1.50)
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a. WHAT reactor building pressure relief system interlock must be satisfiec before a reactor startup can be conducted? (0.50:
b. The reactor building overpressure scram is installed to scram the reactor at less than 3.0 inches of H20. WHAT is the basis for the value of this setpoint? (1.00)
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QUESTION L.04 (3.50)
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a. WHOSE permission is required before a warning tag can be posted AND WHO may post a warning tag? (1.00)
b. HHAT are FIVE (5) requirements which must be observed when "locking out" facility equipment AFTER permission is granted? (2.50)
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QUESTION L.05 .(1,50)
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In accordance with 10 CFR Part 50.54(x), under WHAT conditions can an operator take reasonable action that departs from a license condition or a ,
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Technical Specification? ;
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QUESTI0h L.06 (1.00)
WHOSE approval is required before Temporary Changes to Class B or C procedures may be made?
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QUESTION L.07 (2.00)
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a. Whenever jumpers are used to bypass safety functions. WHERE must a i warning tag be placed so that the reactor is not started until the bypass is removed?
b. In WHAT condition can the reactor be in when Safety Functions, which are required by Technical Specifications as a Limiting Condition for Operation, are to be bypassed for testing purposes?
c. HOW many individuals are required to check the physical installation of a jumper after it has been installed?
d. TRUE or FALSE: !
I Safety Functions which are bypassed during a normal startup by key i
, switches on the scraie panel are logged onto the Bypass Los Sheet? ;
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(2,6o)
QUESTION L.08 cc . o ut
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Using Attachment 2, classify, if applicable, each of the events listed
' below in accordance with PM-4.4. "Emergency Classification System."
d J10'
(/oo)
1. An experiment using bottled hydrogen gas becem = A=--g-d r nulting ir
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the uncan+-e1L_d solease of the gas from its containe _
' 2. A train derailment *- ult; lo une complete rupture or both liquid
__ yas44c oivrage tanks which were full at the time of the acciden .
3. The MIT Campus Police inform you that an anonymous caller has just threatened to damage the reactor buildin l 4. An automatic reactor acram from full power occurs due to the tripping i
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of a primary coolant pum b. Within HOW many hours after an Alert is declared must the NRC be notified? (0.50
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t THEORY Pcgo 48
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QUESTIOl
f(.60] HHA'
H.01 ,'2.00; the sa iuso of the greater relativa nki14+y. M a.1mved neutrons to cause mal fi -
. j due to their lower birth energies (0.50)
. robability for fission)
esir h;ilay ( G . R]
3txo-87 (longest lived neutron precursor) [0.50)
Qa hWG $CL h hat)f.
-: Rt.Lctor Physics Notes Y Y 450 AQdu$lh./]
O'
N' i YA %
krPjn1f3 15, '2 (2.50)
cR1 = 1-Kaf f1/1-Kef f 2 [0.25]
bW7c
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s/2000 = 1-C.9875/1-Keff2 [0.50) . '2 = 0.99375 [0.50)
= 1,59 (Beta) * 0.00736 [0.50] h.4e(fyld Cd.So]
= 0.0124974
' = 0.9875 + Rho
' = 0.9999974 [0.25)
'exicately critical [0,50]
R cetor Physics Notes
- H.03 (2.75)
Po * 10 ' (SUR* time) [0.25]
s= 26.06/T [0.25]
i= 20.06/40 = 0.6515 [0.50)
.= 100 (0.25)
= 10 * (0.6515*t)
i = 2/0.6515 i = 3.07 minutes (0.50)
= (Beta - Rho)/(Rho * lambda) [0.25)
i = (1.0 - Rho)/(Rho *0.1) (0.25)
,a 200.0 Millibeta [0,50)
R:cetor Physics Notes
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E REACTOR THEORY Fcgo 49
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ANSWER H.04 (1.50)
a. Increase (due to less broadening) (0.50)
b. - the neutron will loose very little energy in its collision which will place it right at the resonance capture energy (0.50)
- the neutron is in the fuel where most of the material is U-238 atoms which makes them more likely targets for collisions (0.50) i
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-REFERENCE i
MITR-II Reactor Physics Notes ANSWER H.05 (4.00)
c. Xe production: directly from fission (0.50)
(Beta) decay from I-135 (0.50)
Xe removal: (Beta) decay to Cs-135 (0.50]
neutron absorption (burnout) to Xe-136 (0.50)
Sm production: (Beta) decay from Pm-149 (0.50)
Sm removal: neutron absorption (burr.out) to Sm-150 (0.50)
b. Increases (0.50)
c. 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> (0.50]
REFERENCE MITR-II Reactor Phyqics Notes ANSWER H.06 (2.00)
u. because the rate at which water expands (0.50) increases with temperature (0.50)
b. increased leakage (0.50)
neutron spectral shift (0.50]
REFEREFCE MITR-II Reactor Physics Notes ANSWER H.07 (2.00)
o. because of its lower thermal neutron absorption cross-section (1.00]
b. Photo-neutron production (0.50) by gamma rays (0.25)
from fission product decay (0.25)
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L_ BEACTOR THEORY Pcgo 50
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, REFERENCE MITR-II Reactor Physics Notes ANSWER H.08 (1.25)
Q = M*Cp*(T2 - T1) [0.25]
= 1800 * 8.345 * 60 * 1.0 * 20 (0.50]
w = 1.8025 E+7 (BTU /Hr) / 3.42 E+6 Q = 5.286 MW [0.50]
REFERENCE MITR-II Technical Specifications
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ANSWER H.09 (2.00)
a. to prevent the release of radioactive fission gas into the reactor coolant (1.00)
b. it would increase the delay time for heat removal (0.50) on rapid power increases (0.50)
REFERENCE MITR-II Technical Specifications 5-4 l
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i RADIOACTIVE MATERIALS HANDLING DISPOSAL Pago 51
. AND HAZARDS
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ANSWER I 01 (2.50)
a. ftew 900 eye- C a leak from the tank (3 X 0.50)
ambient temperature <= 32 b. the stack [0.50)
c. the final valve in the discharge path is kept locked closed (0.50)
REFERENCE RSM-8.19,8.20 ANSWER I 02 c.so)
F2. 004 pump one starts (0.50)
- ux; tu
- etarte (0.50)
inlet city water isolates (0.50) .
"Leak Primary D20 System" annunciator alarms (0.50)
REFEPENCE RSM-8.19 ANSWER I.03 (1.50)
a. door must be closed (0.50) and locked (0.50)
b. MITR Radiation Protection Officer (0.50)
REFERENCE PM-3.12.2 pages .
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-I . RADIOACTIVE MATERIALS HANDLING DISPOSAL Pcgo 52
. AND HAZARDS
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ANSWER I.04 (2,50)
a. Di * (R1)*2 = D2 * (R2) 2 (0.25)
100 (mR/Hr) * 10 2 (ft2) = D2 * 1 2 (ft2)
D2 = 10,000 mR/Hr (0.25)
A = Ao * e (-lambda * time) (0.25)
lambda = In2 / half-life (0.25]
lambda = 0.04621 (1/ minutes) (0.25)
100 (mR/Hr) = 10,000 (mR/Hr) * e (-0.04621 * time)
time = 100 minutes (0.25)
b. I = Io * e (-mu * X) (0.25]
mu = ,$/ mass attenuation coeficient * 11.34 (sm/cm3) (0.25)
au = 0^ (ifu-r (G.26)
1 = 100 * e (.-60 * X) g g , f y gpq {,[ p y g].
X = 0.0'S" ( c r. ; (^.25]
REFERENCE b '
MITR-II Reactor Physics Notes ANSWER I.05 (3.00)
a. open window - closed window [0.50]
2.00 - 1.50 = 0.50 R/Hr (0.50] .25 R/Qtr (0.50)
1.25 / 1.50 = 50 minutes (0.50)
c. 3 R/Qtr (0.5r)
5(N-18) R (0.50)
REFERENCE 10 CFR 20.104 ANSWER I.06 (1.50)
N-16 Ar-41 (3 X 0.50]
Hydrogen REFERENCE RSH-3.2.5 l
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__ RADIOACTIVE MATERIALS HANDLING DISPOSAL Pego 53
. AND HAZARDS
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4 ANSWER I 07 (2,00)
a. by detecting the presence of N-16 (0.50) and F-18 (0.50)
b. because of the short lived half lives of the detector sensitive isotopes which are used for tritium detection (1.00)
REFERENCE RSM-7. ANSWER I.08 (3.00)
c. NRC SRO license (0.50]
shift supervisor qualifications (0.50]
b. - notify the Radiaction Protection Officer
- check package for DOT compliance (4 X 0.50)
- perform a survey
-
check shipping papers against purchase order
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REFERENCE PM-1.10 page 18 ANSWER I 09 (2.00)
- a. to save a human life (0.50)
to ensure nuclear safety (0.50]
b. Director of Reactor Operations (0.50)
MITR Radiation Protection Officer (0.50]
l REFERENCE PM-4.3 page 14
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(***** END OF CATEGORY I *****) SPECIFIC OPERATING CHARACTERISTICS Pcgo 54
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ANSWER J.01 (2.25)
When a rabbit is inserted. solenoids (0.25) operate in such a manner that a
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vacuum (0.25) is channeled between the inner and outer tubes (0.25)
Because there are perforations in the end of the inner tube, (0.25)
the opening of a solenoid which applies atmospheric pressure to the outer tube (0.25) causes a differential presuure to exist across the rabbit, (0.25] propelling it to the in-pile limit (0.25] .
The operation is reversed by another set of solenoid valves in order to oject the rabbit (0.50]
REFERENCE RSM-2.10 ANSWER J.02 (1.50)
- a. reduce Argon-41 production (0.50)
prevent nitric acid formation (0.50)
). b. gamma heating (0.50]
REFERENCE RSM- ANSWER J.03 (2.50)
n. During normal conditions, the valves are closed by hydraulic pressure lifting the balls upward (0.25) On a pipe break, the balls drop by gravity opening the valve (0.25] Water then flows out of the core tank and out the break (0.25] This continues until the water level drops to the top of the valves, (0.25) when the flow of water is stopped by air intrusion into the valves (0.25]
b. During normal conditions, the valves are closed by hydraulic pressure lifting the balls upward (0.25] When core flow stops, the balls drop by gravity (0.25) allowing cold water (0.25) to flow downward through the valves (0.25) and up through the core (0.25)
REFERENCE RSM Figures 1.15,1,16,1,17 (***** CATEGORY J CONTINUED ON NEXT PAGE *****)
, _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ - _ SPECIFIC OPERATING CHARACTERISTICS Pego 55
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ANSWER J.04 (2.50)
B10 (n , alpha) Li7 (0.75)
the charged products create ion pairs (0.25)
in the counting gas (N2) (0.25] which are seen as pulses >
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by the detector (0.25] the detector also detects gamma rays (0.25)
so these must be compensated for by another ion chamber without the B10 lining (0.25] this signal is then subtracted from the B10 lined ion chamber's signal (0.25]
the detector is good for intermediate (0.25) and full power levels (0.25]
REFERENCE RSM- ANSWER J.05 (2.75)
a. because it supplies power to operate a motor-driven interlock (0.75)
b. the emergency lighting panel transfer switch immediately connects to battery power (0.50)
the M/G set starts immediately (0.25] but is delayed from loading through a transfer (0.25) for 12 seconds (0.25)
on restoration of power all transfer switches return to their normal positions (0.50] and the M/G set is stopped (0.25)
REFERENCE RSM-8.31.8.32 ANSWER J.06 (2.00)
- the ventilation is secured
- the containment shell is sealed
- the top part of the D20 reflector is dumped (4 X 0.50)
- the withdrawal permit circuit is interrupted causing the shim blades to drop REFERENCE RSM- (***** CATEGORY J CONTINUED ON NEXT PAGE ******
, . ._ SPfCIFIC OPERATING CHARACTERISTICS Pcto 56
.
.
ANSWER J.07 (1.50)
a. D20 freezing could occur (0.50)
b. - shift cooling tower fans to low speed
- adjust cooling tower slate [2 X 0.50)
- bypass flow to basins REFERENCE PM-5. ANSWER J . t.'e (1.00)
to allow the reactor core and primary coolant to approach thermal equilibrium (0.50] thereby reducing stress on the fuel element and cladding (0.50]
REFERENCE PM-2. ANSWER J.09 (2.00)
- all shim blades must be above the suberitical interlock position
- the deviation between power-set and actual power must not exceed 1.5%
- the regulating rod control switch must be in the neutral position
- the regulating rod must be withdrawn beyond its near-in position (4 X 0.50]
REFERENCE RSM-4,4 ANSWER J.10 (2.00)
- maintain the purity of the primary H2O
- maintains core level by means of a continuous overflow [4 X 0.50)
- provides for a surge volume
- provides cooling flow through the H2O medical shutter tank
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_ _ - _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ . FUEL HANDLING AND CORE PARAMETERS Pcgo 58
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ANSWER K.01 (2.00)
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a, to prevent personnel entry into the reactor building (0.50)
b. fuel storage ring (0.50) ,
transfer basket (core flow guide) (0.50) i c. ensure adequate shutdown margin (0.50)
REFERENCE ;
PM-3.3.1 page 2 PM-3.3.2 pages 3,4
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ANSWER K.02 (3.50)
a. five by five (neven by seven) matrix of open-ended boxes (0.50)
in an aluminum frame (0.50) OA CaMe &&M made of aluminum-cadmium-aluminum sandwich (0.50) CA. CC4muu,m b, [
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used for corrosion resistance (aluminum) (0.50)
neutron absorption characteristics (cadmium) (0.50)
b, decay heat removal (0.50]
shield personnel from gamma radiation (0.50)
i REFERENCE i RSM-8.38
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ANSWER K.03 (1.50) l a. four (4) days (0.50] l b. Prevent melting from afterheat (1.00)
REFERENCE ;
MITR-II Technical Specifications 3-39 f l
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ANSWER K.04 (1.00) i
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- regulating rod absorber (0.50)
control (shim) blade (0.50)
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REFERENCE PM-3.4.1.3. ANSWER K.05 (2.00)
o, check that there are no loose or unattached items in their clothing (affix loose items with tape) (1.00)
b. low power safety amplifiers must be replaced by full power safety amplifiers [1.00)
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REFERENCE
l PM-3. ANSWER K.06 (3.00)
I o. the total worth of the rod is to be limited such that the complete
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withdrawal of the rod will not (125: t'e rera+^- r-^==^ i: 1) cause
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b. in the event of an accidental continuous insertion of reactivity at the above maximum rate, the responsJ of the reactor safety system period and level trips will adequately protect the reactor (1.00)
c. the additional independent capability for reactivity control provided by i
the D20 reflector dump gives added assurance that the reactor can be l made suberitical under an adverse condition of fuel loading or control blade malfunction (1.00]
REFERENCE MITR-II Technical Specification 3-32 thru 3-35 l
ANSWER K.07 (2.00)
- loss of power to the SPSP control and alarm panel
- a leak from the pool
- low SFSP water level (4 X 0.50)
- low flow thru the SFSP ion exchanger REFERENCE PM-5.7.12. "Spent Fuel Storage Pool." page 1 (***** CATEGORY K CONTINUED ON NEXT PAGE *****)
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ANSWER K.08 (1.50) ;
a. senior reactor operator (0.50]
superintendent (0.50)
b. 1.0 KW (0.50)
i REFERENCE :
PM-1.15 I
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a. it is axially symmetrio (0.50)
b. The burnable poison has a high absorpt oss-section for thermal !
3e neutrons (0.50] so its negative vity worth initially compensates t
"r- i for the reactivity wort e added U-235 (0.25] ;
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competi ocess (0.50] !
T echanism delays the decrease in reactivity worth of the fuel !
element, thus increasing its life (burnup) (0.25) >
o. maximises (0.25) flux and power (densities) (0.25) in the lower half of i the core (0.25) !
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minimises (0.25] power (peaking) [0.25) l
- in the top half of the core (0.25)
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L, ADMINISTRATIVE PROCEDURES. CONDITIONS Peso 61 I
, AND LIMITATIONS !
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ANSWER L.01 (2.50)
a. prevent mechanical damage to the components (0.50)
prevent core reactivity changes due to movement (0.50)
assure proper flow distribution and cooling (0.50)
(ensure validity of safety limits)
b. so as not to appreciably affect core power distribution (1.00)
(hot channel factor or peaking factor)
REFERENCE MITR-II Technical Specifications 3-41 ANSWER L.02 (2,50)
a. neutron flux main tank coolant level (3 X 0.50)
primary coolant outlet temperature b. loss of power automatically scrans the reactor (0.50)
coolant will still cover the core (melting will not occur) (0.50)
REFERENCE MITR-II Technical Specifications 3-23 ANSWER L.03 (1.50)
a. minimum negative differential pressure (0.50)
b. prevent reactor scram on momentary low positive pressure (0.50) which may occur after a ventilation shutdown (0.50)
REFERENCE MITR-II Technical Specification 3-10 (***** CATEGORY L CONTINUED ON NEXT PAGE *****)
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ANSWER L.04 (3.50)
o. on duty console operator (0.50)
any member of the NRL/RPO staff (0.50)
b. - SRO vill witness lockout
- SRO will verify safe system condition (any 5 0 0.50 each)
- person performing work will perform lockout
- person performing work will retain the key on his person
- a notation as to the system being locked out shall be made on the status board
- the system must be tagged out REFERENCE PM-1.1 ANSWER L 05 (1.50)
in an emergency (0.50)
when the action is needed to protect the public health and safety. (0.50)
and no other action is immediately apparent (0.50)
REFERENCE 10 CFR Part 50.54(x)
ANSWER L.06 (1.00)
two (2) reactor staff members (0.50) one (1) of whom shall hold an SRO license (0.50)
REFERENCE PM- ANSWER L.07 (2.00)
a. on the shim blade control handle (0.50)
b. shutdown (0.50)
c. two (2) (0.50)
d. FALSE (0.50)
(***** CATEGORY L CONTINUED ON NEXT PAGE *****)
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' . AND LIMITATIONS '
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4. No Classification b. 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> (0.50] o REFERENCE h i
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ANSWER L.09 (3.00) ,
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- if the probability of occurrence or the consequence of an accident or i malfunction of equipment important to safety previously evaluated in the l SAR may be increased (1.00) (
- if a possibility for an accident or malfunction of a different type than any evaluated previously in the SAR may be created (1.00) f
- if the margin of safety as defined in the basis for any Technical l Specification is reduced (1.00) !
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ATTACHMENT 3 l .
- Facility Coseents on R0 Exas. 12 Sept. 88 A.02 Source is not installe A.04 At 298 kW, the tempe rature change is still insignifican The period would still be 60 seconds. (Note PM 2.3 does give 100 kW as the point of adding hea We shift to cooling towers at 250 kW and begin seeing temperature effects on the approach to 1 W. PM 2.3 p.3 is in error.)
R.02(a) Also, avoid activation of argon, and Provide inert medium for transport of disassociated D /02 to recombine C.04(c) Answer should be 'In'. On flooding, which would be with D 20, a positive reactivity addition is mad (If light water flooded it, the answer is correct, but the blister tank is surrounded by heavy water.)
l D.03(e) Must have 1800 spe for full power operatio For 100 KV operation, not require E.03(a) Should be flow ' guide' not ' shroud'.
E.03(b) Typo ' bank' should be ' tank'.
E.07(c) Current setpoint is 95 sp It varies, but is always above minimum required of 75 sp F.03(d) Refer to FM 5.2.1 and FM 5.5 4. Weither requires an tenedi-F.03(e) ate shutdow Both allow time to investigate and both l
i require shutdown by ARI if certata conditiona exis Not sure how these should be answere C.05(b) 'MV-83 and NY-64 are referred to as the ' solenoid valves'.
Mesortsation of valve numbers is not require _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ - _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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- Facility Comments on SR0 Exas, 12 Sept._1988 H.01a Concur that Il > 8 because of their lower birth energies. As a result they have a lower probability of undergoing fast neutron leakage and to a lesser extent resonance captur So, we agree with giving credit for "lower birth energies".
We disagree with giving credit for 'cause thermal fission'
because once thermalized both prompt and delayed have same probability of causing fissio H.02b The MIT Reactor uses fully enriched fue There is very little U-238 and hence little plutonium buildu Beta-effee-tive does decrease on the MITR-11 with core life because the blades are withdrawn further making the effective core volume large Hence, there is less leakage of prompt neutron Recall that from fH.01a, the principal dif ference between prompt and delayed neutrons is the leakage probabilit Any-thing that decreases leakage decreases that differenc H.03a It is not necessary to use startup rat Probles could be solved directly (and more easily) using perio H.04a Reason given in answer (lest broadening) is correct but the effect is to decrease (not increase as indicated in the answer) the capture cross-section. Also, MITR fuel tenpera-ture varies only over a range of 30'C from aero to full powe So, the effect is quite smal H.05b By definition, the shutdown margin is calculated by subtract-ing out xenon. So, the answer should be 'No Change'. If the question meant "by how much would the reactor be shutdown",
then the answer is ' Increase'. (Notet Believe this point of confusion was discussed by the examiner during the test.)
H.08 Question should provide value for specific heat of wate ,_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ . _ - _ _ _ _ _ _ _ _ _ . ._____ ____ __-_ _ _ _ _ _ _ _ .-
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I.01a Typo in answe It should.be ' level' not ' flow' greater than 900 gallons (not spa).
I.02 The sump systes was recently modifies'. There is now only one pum .04b Typo on unit Should be 0.189 ce /2 gra Hence, in solu-tion, saltiply by density instead of dividin Amewer is about 2 c I.09b Note: Director of Operations and Emergency Director may be the same perso .
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d J.05a The 13.8 KV breakers are the property of the Cambridge Electric Compan The Reactor Staff is not allowed to operate the Hence, question is not relevan J.10 Also provides shutdown cooling (decay heat removal) when reactor is shutdow This is a fifth function of the cleanup syste R$N 3. .
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, K.Olb Answer is correct but note that fuel suet 30 from the storage Jing to the baske It can not go direct from the storage rin K.02 Currently two types ,of boxe One is aluminua-cadstus-aluminum, the other is cadmium-line K.06a A 1.8% delta K/K insertion will nahe the reactor prompt critica The answer should be that such an insertion will not cause a transient that is beyond the capability of the safety systes to shut down the reactor before fuel damage occur K.04 The answer is correct but the question's wording is confus-in The safety and operating limits must be verified before going above 1 K The SR0 and Superintendent sign for doing that evaluatio K.09a Also, radially syssetri K.09b The MIT Reactor does not use burnable poison K.09c Answer is correct but inserts are currently made of boron stainless stee .
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L.02b Also, minimus required equipment is provided by self-contained power supplie '
L.03 Answer given is correc However, please see also PM 5. "Building overpressure", which gives other f actors involved in selecting the set poin L.06 Must be two licensed reactor staff members, one of whom holds an SR0 license for Class 3. For Class C could be two staf f members, one of whom has an SR L.04 Attachment heo was FM 4.4 page 1- These pages provide general advice and they are not the EA14 given in the proce-dures. Hence, this question is difficult to grade. Commente are as follows:
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l (1) An H2 release would be an event. The probability of i probles has been increased, but no radiation release has
occurre i l (2) A waste tank rupture would be an aler A radiation
- release has occurred, it is limited in extent by the finite tank volume, and it is well below levels for site
! energenc Waste tank activity is never more than a few sillicartes, if that.
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(4) Not classifie Talls within scope of AOP !
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NRC Response to the Facility Coments A.02 Coment is valid and point count will be distributed as indicated in the answer sheet. The answer sheet anticipated this comen A 05 Coment is accepted. Answer key will be change B.02a Coments are accepted. Answer key will be changed to include these answer C.04c Coment valid. Answer key will be change D.03e Coment valid. Answer key will be change E.03a Coment accepted. Answer key will be changed. Suggest change be made to Reactor Systems Manual p. E.03b Coment valid. Answer key will be change E.07c Coment accepted. Answer key will be change F.03d The question states that no othe- abnormal condition occurred, therefore F.05 (d) answer is NO SHUTDOWN REQUIRED (error in answer key).
F.03e The question states that no other abnormal condition occurred, therefore F.03 (e) answer is NO SHUTDOWN REQUIRED (answer key is correct).
G.05b Coment is accepted. Answer key will be change H.Ola as changed to: "because delayed neutrons have lower The birthanswer key w(0.50] which results in fewer delayed neutrons from energies
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[0.50 lost from the neutron cycle during the thermalization proc < ass It.0lb the question was deleted due to the lack of a reference. The value of the question was reduced by 0.50 point H.03 Either method is acceptable and since the answer does not change, no change was made to the answer ke H.04a No changes were made to the answer key. The answer is correc (Increase), since at the resonance energies the capture crost section Increases at lower temperatures. refer to Figure 4-2b.
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o-2-H.05b The answer key was not changed because the candidate was informed during the examination that Actual Shutdown Margin was "the amount by which the reactor would be shutdown."
~I.01a The answer key was changed to: "level -
900 gallons." Please revise RSM-8.20 to correct this erro I.02 The answer key was changed and the value of the question was reduced by 0.50 point Please revise RSM-8.19 and any applicable drawing I.04b The answer key was changed to reflect the typo in this questio The correct answer is 2.15 c .09b The answer key was not changed because the reference material indicates unly two (2) individuals: the Director of Reactor Operations (DRO) and the Radiattun Protection Officer (RPO).
However, if the full emergency organization is activated, then the DRO is the Emergency Directo J.05a The answer key was not changed because the 13.8 KV circuit breaker motor-driven interlock is one of the loads which is directly supplied off the 125 VDC battery suppl J.10 The ans.er key was changed to include a fifth correct answer:
"provides for decay heat removal."
K.02 The answer key was changed to accept both answers for full credi K.06a The answer key was changed by deleting the non-required, bracketed portion of the answer. The answer is still correct since the SAR shows that a 1.8% delta K/K is the limit for a step reactivity insertion without fuel damage occurin K.59a The answer key was not changed because axially synnetric is the only answer which could be reference K.09b The question was deleted thereby reducing the value of the question by 1.5 points. Please revise RSM-1.4 to reflect this non-use of burnable poison K.09c The question, if used in the future, will be revised accordingl L.02b The answer key was not changed b>cause a reference for the alternate answer was unavailabl L.03 The comment was reviewed but all other alternate answers did not have adequate justification to qualify them as a basis for the scram setpoint. The answer key was not changed.
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e -3-L.06 The answer key was not changed since the Class B criterit: are more stringen L.08 The question should have included PH-4.5, "Emergency Action Levels."
L.08a and L.08b will be deleted because of inadeqaute informatio The value of the question was reduced by 1.00 point ;
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