IR 05000054/1987002
ML20213G279 | |
Person / Time | |
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Site: | 05000054 |
Issue date: | 05/08/1987 |
From: | Coe D, Collins S, Keller R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
To: | |
Shared Package | |
ML20213G260 | List: |
References | |
50-054-87-02OL, 50-54-87-2OL, NUDOCS 8705180216 | |
Download: ML20213G279 (60) | |
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t 8 U.S. NUCLEAR REGULATORY COMMISSION-
REGION I
REQUALIFICATION EVALUATION REPORT Report N /87-02(0L)
Docket N License N R-81 Licensee: Cintichem, In P. O. Box.324 Tuxedo, New York 10987 Facility: Cintichem Reactor Examination Date: March 27, 19 Chief Examiner: )
. Coe,' Lead Rea
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. Engineer (Examiner)
67(/7 7 Date Reviewed by: 6-/f!f/5f7 R. Keller, ChieT, Projects Section 1C Date
., Approved by: Ilmud/ dill /M SldB7 Sf J. Colli 6s, Deputy Director Date Division of Reactor Projects Summary: The NRC administered written requalification examinations to two
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operators and eight senior operators out of 18 licensed operators at this facility. This examination was conducted in response to a substantiated alle-gation that facility administered written requalification examinations were not properly proctored (NRC Inspection Report No. 50-54/86-02, unresolved item 86-02-02). The present examination results indicate a generic weakness in the licensee's requalification training program in the area of principles and
theory of reactor operation.
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h 8705180216 870508 PDR ADOCK 05000054 V PD ._ - _ - . _ . - ~ . - _ - _ - . .. -- -. . , , _ . . . - . _ . . _ . _ . - ..- - - . _ , -
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REPORT DETAILS TYPE OF EXAMS: Requalification EXAMINATION RESULTS:
RQ Category A B C D E F G OVERALL Pass /Fai1* 2/0 1/1 2/0 2/0 2/0 2/0 2/0 2/0 SRO Category H- I J K L OVERALL Pass /Fai1* 2/6 8/0 7/1 6/2 8/0 6/2
- Pass / Fail criteria in accordance with facility licensee's approved train-ing program.
- Exit Interview NRC Attendee D. H. Coe, Lead Reactor Engineer (Examiner)
Facility Attendees W. Ruzicka, Operations Manager S. Lapinski Examination Review:
At the conclusion of the written examination a brief review was conducted by members of the licensee's staf The examiner indicated that two changes to the examination were made during its administration and answered questions regarding the examination content. No resolutions of facility concerns was made onsit The facility submitted written com-ments on the examination within the five day period allowed (Attachment 3)
and the NRC resolved each of these (Attachment 4) before final grading was complete . Analysis of Results The high Section H failure rate indicates a generic weakness in the principles and theory of reactor operatio The following specific ,
weaknesses were noted:
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-3 Operators were generally unable to discuss why the maximum Kexcess value for the pool must be less than' for the stall in order to meet the basis of the specificatio Operators could not predict the effect of a pool temperature increase on indicated and actual reactor powe Operators were generally unable to calculate the reactivity effect of Xenon given initial reactivity and initial / final count rate informatio Some operators were unable to correctly interpret the meaning of an
"inaccurately low reading" on a commonly used instrumen Some operators had difficulty distinguishing between the terms production (of an isotope) and quantity (of an isotope) Conclusions The facility requalification training program requires upgrading in the area of principles ard theory of reactor operation.
Attachinents: R0 Written Requalification Examination and Answer Key SR0 Written Requalification Examination and Answer Key Facility Comments on W.'itten Examinations NRC Response to Facility Comments
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- -0 NUCLEJ.R REGULATORY COMMISSION
- * REACTOR OPERATOR REQUALIFICATION EXAMINATION FACILITY: _ UNION _ CARBIDE _CQRP._____
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REACTOR TYPE: _TESI____________________
DATE ADMINISTERED: _8ZL9}f2Z________________
EXAMINER: _ S I L E.1_ D . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
CANDIDATE: __b M h d____________
INSIBUCIlQNS_IQ_COUDIDOIE1 Read the attached Instruction page carefully. This examination replaces the current cycle facility administered requalification examinatio Retraining requirements for failure of this examination are the same as for failure of a requalification examination prepared and administered by your training staf Pointu for each question are indicated in parentheses after the questio The passing grade requires at least 70 in each category and a final grade of at least 70%. Examination papers will be picked up four (4) hours after the examination start % OF CATEGORY % OF CAND I DAT E ' S CATEGORY
__Y66UE_ _IQIOL ___SCQB[___ _yGLUE__ ______________CGIEGQBX_____________
__D.69__ _14 22 ___________ ________ PRINCIPLES OF REACTOR OPERATION
__9169__ _1d122 ___________ _________ FEATURES OF FACILITY DESIGN
__a,.59__ _13miz _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ . _ _ _ GENERAL OPERATING CHARACTERISTICS
__g.79__ _13 59 ___________
__,_____ INSTRUMENTS AND CONTROLE
__StS9__ _14t1Z _ _ _ _ _ _ _ _ _ . . . ________ SAFETY AND EMERGENCY SYSTEMS
__StZO__ _19 59 ___________ ________ STANDARD AND EMERGENCY OPERATING PROCEDURES
__@t49__ _14 99 ___________ ________ RADIATION CONTROL AND SAFETY
_b9c99__ ___________ ________% Tntals Final Grade All work done on than e:: ami na t i on is my ow I have neither given nor received ai . - _ . . _ _ _ _ _ . - _ _ _ _ _ _ _ _ _ - . - . _ _ - - . _ _ -
Candidate's Signature
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NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS 1 ?
During 'the administration of this examination the following rules apply: Cheating on the e::ami nati on means an automatic denia1 of your app 1ication and coul d resul t in more severe penalties. 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 cheating. Use black ink or dark pencil goly to facilitate legible reproductions. Print your name in the blank provided on the cover sheet of the examination. Fill in the date on the cover sheet of the e;: ami n at i on (if necessary). Use only the paper provided for answers. Print your name in the upper rioht-hand corner of the first page of each section of the answer sheet. Consecutively number each answer sheet, write "End of Category __" as appropriate, start each category on a new page, write gnly gn goe side of the paper, and write "Last Page" on the last answer sheet. 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 litecatut . The print value for each question is indicated in parentheses after the questiin and can be used as a guide for the depth of answer require . Show al - lculations, methods, or assumptions used to obtain an answer to mathematical problems whether indicated in the question or no . Partial credit may be give Therefore, ANSWER ALL f* ARTS OF THE QUEG110N AND DO NOT LEAVE ANY ANSWER DLAN . If parts of the e::aminat i on are not clear as to intent, ask questions of the egami_ger onl . You must sign the statement on the cover sheet that indicates thet the work is your own and you have not received or been given assistance in completing the e::aminati o This must be done after the e:-: ami n a t i on hat, been complete ", .
10. Whdn you complete your c:: ami n a t i on , you shall: Assemble your examination as follows:
(1) Exam questions on to .
(2) Exam aids - figures, tables, et (3) . Answer pages including. figures which are part of the answe Turn in your copy of the examination and all pages used to answer the examination question Turn in all scrap paper and the balance of the paper that you did not use for. answering the question Leave the e:: amination area, as defined by the examine If after leaving, you are found in this area while the examination is still in progress, your license may be denied or revoke '
Ot__EBIUGIELES_OE_BEOGIDB_OPEB8IlgN PAGE 2
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QUESTION A.Ol' (1.00)
Pr i m,ar y f l ow r at e is 2300 GPM. Secondary flow rate in 2380 GPM. If the primary delta-T across the heat e:: changer is 15 degrees F and the second-ary inlet temperature is 80 degrees F, what is the secondary exit temp-erature?
OUESTION A.02 (1.50) The reactor is started up and K-excess is measured to be 6.0% delta k per k. .lf the pool temperature had been 10 degrees F higher when the K-e:: cess measurement was made, estimate what K-excess would be and e::p l ai n why it change .03 At what react 2vity value would the reactor be critical on prompt neutrons alone? C0.5]
OUESTION A.03 ( .85)
Would an inaccurately low reading for coolant flow rate during the procedure to calibrate the Power Level normal channels result in actual reactor power being higher or lower at the moment of a high power scram?
OUESTION A.04 (l.50)
What effect would an increase of lOF in pool water temperature havt on actual reactor power assuming the rod control system is in the Linear N mode? Explai QUESTION A 05 (1.50)
Explain how and why the peal / average thermal f l u:: ratio would change if a steel canister (void can) were placed no::t to the core and power were held constan (***** CATEGORY A CONTINUED ON NEXT PAGE *****)
'si__EB10GIE6E@_gE_BEOGIQB_9EEBOllgN PAGE 3
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QUESTION A.06 ( .75)
Whicp orie of the fol1owing descriptions best supportr, the rcason why Xenon reactivity increases sharply after a trip following 1000 hr of oper a t i on at 100% power ?
A) Xenon decays less rapidly due to a reduction in the neutron flu B) ladine half-life is-much shorter than Xenon half-lif C) Iodine production is greatly reduced and Xenon production is greatly increased due to the reduction in neutron flu D) Due to reduced neutron absorption, Iodine concentration increases, and Xenon decays directly from lodine, thus Xenon increase QUESTION A.07 (1.50)
Explain why the reactor must be made subtritical prior to movireg the fission chamber if below Log-N confidenc (***** END OF CATEGORY A *****)
92__EE@ lube $_9E_E6g1611X_ DESIGN PAGE '4
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QUESTION B.Ol (1.00)
WHAT, prevents the accidental gravity draining of the pool to the 100,000 gallon-storage tank?
DUESTION B.02 (2.00) TRUE or FALSE: The secondary (rabbi t container) irradiation contain-ers are. designed to be leak-tight for gase (0.5) WHERE are the rabbits from the two pneumatic tubes placed in the high flux region (relative to the core and beam tubes)? (1.0) WHERE does the constant exhaust system that inserts and removes the rabbits vent to? (0.5)
OUESTION D.03 (l.00)
Why is the water tight gabket seal on the outside of the shield for the beam tube rather than on the inside?
DUESTION It. 04 (1.50)
During normal full power operation the flapper valve fails to the f ully open position without initiating any trips or interlocks. What indicat-ion will the operator have that this has occurred? Explai QUESTION D.05 (i.50)
For each of the following parameters provide the normal limits and the method by which the parameters are maintained within limit Primary water PH Secondary water blow down rate Dumineralizer exit water specific activity (***** CATEGORY D CONTINUED ON NEXT PAGE *==++)
D2 _EEG1gBES_OE_[QQ1LlILDESl!hU PAGE D
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QUESTION D.06 ().60)
. St:e t,c h the flowpath of primary coolant during normal forced convection mode cooling using a single line diagram. Include only those components which are di r ectl y in the primary and purification flowpath T h r-reactor is in the stal (***** E NI) DF CATEGORY lt *****)
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QUESTION C.01 (l.50)
W h,a t five outomatic actions wi11 i mmed2 atel y occur when the emergency ventilation system is initiated?
OUESTION C.02 (1.20)
During reactor operation at full power, a seat leak develops in the valve connecting the discharge of the primary coolant pump to the storage tan The leak rate is about 10 GPM. What would be four probable indic-attons that this leak had developed?
OUESTION C.03 (2.40) Explain what will happen, in terms of the electrical system, if all normal power is los E1.2] What manual steps or automatic actionr. must occur to restore the normal electrical 12neup after operation in the ernergency lineup?ti.2')
OUESTION C.04 (2.00)
Following the loading of a new core configuration, the control rods ar e calibrated and the Regulating Rod is found to have a total worth of 0.61 percent delta-K/ Is this acceptable? E>:pl ai n why or why not, What meaesures coul d you take to change the worth of the Regulating kod?
'DUt5ST 05 (1.40)
If the flapper valve - tehut following a lote of normal electrical power scram from entended ful cieration, describe how the contral rcom andicatians would differ f r dm-+hur e normal 1y enpected had the fIapper valve opene Do not c on srttu he fIapper
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valve pouition indicatio (kC(<'ft (***** END OF CATEGORY C *****)
0,.__1U516uggNIS_8ND_CQNIBO!=5 .PAGE 7 l
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QUESTION D.01 (2.00)
a, At what point is the plant considered to be in the heat range? (O.S) What action is taken to adjust instrument power to the heat (0,5)
power? Give two reasons why UIC's and CIC's are not used for determining heat powe (1.0)
DUESTION D.02 (1.60)
LIST four events or actions which would cause a transfer from Auto to Manual rod control operatio DUESTION D.03 (1.00) After the reactor is shut down describe how the compensation on the Log N channel will change with no operator actio [0.53 Gamma c ompenua t i ore le riot required in the power range for teveral rent-on WHICH of the statements below is NOT one of those reasons? (0.5)
1 Decay gamma flux is insignifitont in comparison to the neutron flua 2 Fission gamma fiua contributes appro:: A ma tel y 1 */. o f thermal power 3 i'ower r arige instruments are calibrated to the heat balance 4 Fission product dec e y gainmas t.ause decay heat which can be appronimatel y S -7 percent of thermol power DUESTION D.04 (1.60)
Liut the interlocle that i rihi bi t rod withdrawa QUEST 1ON D.05 (1.00)
The N-16 and Delta T i nt t r ument e, or e the most accurate meann of deter--
mining core powra Why or e these not used as t.a f o t y channeln?
(***** CATEGORY D CONTINUED ON NEXT PAGL +==**)
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DUES 11ON D.06 (1.00)
What, would be the e: pected change to the primar y flow indication in the control room if bloct: age were to occur precisely at the flow measuring orifice? E> pl ai QUESTION D.07 ( .50)
If a RTD shorts, its temperature indication will increase. TRUE or FALS (e**** END OF CATEGORY D eansa)
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E,.__SOEEIY_6ND_gt!ESQEUGL Q1SIEMS PAGE 9 l l
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WttAT SCHAMs protect the reactor above 2nL? Exclude manual SCRA (1.5)
DUESTION E.02 (1.50)
EXPLAIN how the core would be cooled in the event of a loss of pool water .
INCLUDE the source of water and HOW it would be initiate DUESTION E.03 ( .50)
At WHAT value of charcoal filter offattency is a reactor shutdowls required?
DUESTION E.04 (l.60)
Give four indications of fuel cladding failur DUESTION E.05 C. 00) What conditions will autonmtically put the emergency e vacuati oni system into operation? (1.0) The Connole operator accidental 1y initiates the building evacuation sequenc lo an immedaate reactor shutdown warranted'.' Explain.(1.0)
DUESTION E.06 (l.40)
If ulectrical power from the 1ocal power company fal1ed after the initial seven second timing cequence for the emergency venti 1atiun system had been completed, how would the main dampers and main exhautit fan respond to power ramtoratton from the umergency generator" Why?
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(***** END OF CA1EDORY L *****)
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QUESTION F.Ol (1.50)
Wh,at two conditions munt be met prior to allowing maintenance on a com-ponent near the reactor core which could cause a reactivity change?
DUESTION F.02 (1.50)
What actions, if any, need to be taken so that a fuel element can be loaded into a previously blocked center position?
. DUESTION F.03 (2.40)
I ndi c ate whet hs.:r each of the f ollowing situations would require immediato shutdown of the reactor . Consider each si tuation separatel y and ',Just r i y
ycur answer (for a shutdown) or exp1ain your actions (ii shutdown is not required). ,
a. Rods are betnu withdrawn and are at 10 inches while raising power above 2NL on a 45 soc period.
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b. The personriel airlock interlocks can.ome inoperabl c. The normal reactor building exhaust fan trips and cannot bo
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DUESTION F.04 ( 1. &.> )
WHAT three conditions constitute a violation of reactor building containment?
l DUEGTION F.05 (1.50)
- Facility rules r equire not i f ication of the Senior Operator in the event
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of a startup following on unscheduled or unplanned shutdow The t.entor operator need not "i n at t o: ndante" for three conditions. What are they?
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(=aaae END OF CfiTEGORY F *****)
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QUESTION G.01 (1.00)
a.If, a reactor operator is assisting an experimenter in the handling of a
, previously stored sample,.and is able to remove the sample from the pool and perform all the necessary monitoring, under what condi tions woul d be be required to obtain H.P. coverage prior to transfering the sample into a shielded container? [0.53 b.If t he above conditions were NOT met , and the experimenter wanted to
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open the samplo, is HP coverage required? [0.5J DUESTION G.62 (l.70)
After an ancident, a sur vey is niade of the af f ected ar ea wi th a Cut r e-Pi T he wiridow open indication is 6.4 R/hr, window closed is 4.6 R/hr -
at 2 feet, How long can you remain in this area without exceeding your normal quarterly whole body limit? [1.03 Would a G. M. meter be used 1n this case? Why or why not? IQ.73 OUESTION O.93 (l.50)
Li st 3 of 4 process system nia i n t enant e tau s which should have, by procedure, direct health physics surveillance and are normally reserved ior day shift?
i OUESTION G.04 (1.00)
What personn may au t h or i :' e the ube of ewraerity vent il ation during conditionn of high airborno activity when it appearn advisable to evacuate the building?
DUEST!ON G.05 (1.60)
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Lint the three alarm conditions which requiru immediate shutdown of the ruactor and initiation of the evacuation sequence, i
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(***** CATEGORY G CON 11NUED ON NEX T f > AGE * * * * * )
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. OUEST10N G.06 (1.60)
You have been assigned to escort a group of visitors throuoh building 1 and What is the maximum group size you alone can escort? How are visitors packages, handbags, etc. handled? What minimum dosimetry is required for the visitors? On visitor une::pectedly brings his 12 year old so Under what conditions can the boy accompany hi s f ather on the tour? LO.4 each3
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(***** END OF CATEGnFW G *****)
(************* END OF ixnMINhilON ***************)
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IANSWERS'- : UNION CARBIDE-COR G7/03/27-SILK, .. g .
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i ANSWE,R cA.01 (1.00)'
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(m Cp' Delta T)1 = (m Cp Delta T)2 Co.53
'(2300) (15).'=' (2300) ' ( x '- 80) -
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x =94.5.F' EO.53 REF ERENC E --- ,
Cintichem Exam Bank : j Ep r. 7. c.n g/ c e * p're e f d c. CA F ANSWER A.02 ( l'. 50 )
' K-encess = 6.0% - (O.OO44%/deg F ) (10 deg F) = 5.956% CO.53 K-excess .i s smaller because the negative steady state temp coef ficent has.added negative reactivit [0.5]
. +0.81% delta k/k +or- 0.01%' [0.53 REFERENCE DS-01-1_ s <
ANSWER A.03' ( .85)
-O "'- det Cp " nut - Tir' E 9. 29-ifim dot ie 1 ee , Ocalc 4e I ci- w r' cm t : a t her - -1 p n:cr i 'ighir. E^.253 MT n .- o e n 1 4 h ,- a n a + n ncni r .m a u411 +se. ge e. g . eed la CO.053
Thus, actual reactorspower will be HIGHER at the scram cetpoint. [0.,9() J 3
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REFERENCE T/S pg. 9'and equ'ation sheetJprovided
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ANSWER- .(1.50)
4. - . l- v .:j
.As temperature increases more fast neutrons escape. NI's measure */
fast neutrons. [0.753 is maintain constant- i ndi cated power t . 253
. Linear N wi'11 i r.tr 2 cd-
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Actual reactor power would be lower. CO.53
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i REFERENCE OC4: Nuclear Energv Training, Module 3 Rx Ops, Unit .
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, . c
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ANSWER A.05 (1.50)
The ratio will irmrease [0.53 because the f l u:-: will increase in the center of the core since the canister will not reflect neutrons bac to the periphery of t h e c or e. .Lurtr7
/. o REFERENCE 054: RM - 10-5 R.R. Burn 1984 Chapt 9 Intro to Nucl. Reac. Op ANSWER A.06 ( .75)
B (0.5)
REFERENCE res . = c + n .- Tsnrrm ,msgon ii mrv -so_y r r. g _ nt;
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j c ,: SF1 CRDS/OOO E5.33 ANSWER A.07 (1.50) ff /,. , n, h,,, m / A p f, , , p, ,
No change should be made to the reactivity Eof the tore unless dependable power indication is aval1able. [U.753 (Moving iission chamber changes the reactivity of the core.) Log-N below confidence indicates unreliable power level indication and fission chamber cannot provide accurate indication whil e bei ng moves'# [0.753 .
REFERENCE 054:RM-03-5
L%__EE01UBES_oE_EeC161Iy_DESl@N PH6L lb
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, e o I
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ANSWE;R B.01 (1.00)
The bottom of the storage tank is about 8 f eet above the pool surface (1.0)
REFERENCE Union Carbide Nuclear Reactor: Training Manual, B- ANSWER B.02 (2.00) FALSE CO.53 Core face, Just above the number five beam tub E1.03 Stack 00.53 REFERENCE Union Carbide Nuclear Reactor: B-11,1 XG-03-07 ANSWER B.03 (1.00)
With the gasket away from the higher radiation area, conventional rubber base materials can be use (1.0)
REFEPENCE Union Carbide Nuclear Reactor: B-11 ANSWER D.04 (1.50)
The plenum leak alarm will be actuated (0.5). Any leakaae at the flapper valve seat, or in the plenum (0.5), is monitored by a plenum leak detector that senses plenum pressure increase (0.5).
REFERENCE Cintichem E::am Bank: B.29 T/S pg. 28
Ba__EEQIyBE@_QE_E@CILily_DE@lGN PAGE ' I t>
ANSWERS -- UNION CARBIDE COR /03/27-SILL, . e
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ANSW B.05 (1.50) PH 5- [0.23 maintained by domineralizer EO.33 gpm EO.23 vary blowdown rate EO.3] Exit activity <2000 cpm /ml EO.23 regenerate deminerilizer EO.33 REFERENCE 054: RM-06 RS-10-1 ANSWER B.06 (1.60)
see sketch core exit valve HUT HUT e::i t valve primary pump and discharge valve demin pump and suction and disch valves demin and return valves (2)
heat exchanger and outlet valve
_. 5 'I inlet val ve EO.2 each]
REFERENCE Figure B-7
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, e =
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ANSWER C.01 (1.50)
RB supp)y ians shutdown Pool sweep damper closes Holdup tank vent line and air purge valves close All supply dampers close Beam tube exhaust fan shuts down [0.3 each)
REFERENCE 054:RM-07-4 ANSWER C.02 (1.20)
Increasing level in the storage tant:
Decreasing level in the Rx pool ,
Pressure reading in pump r oom ( c ,- /c ..- -/s .-)
Low level alarm in the hold-up tank Checi: valve shuts Pump cavitates [Any four, 0.3 pts each]
REFERENCE 054: RM-03-2 Flow Diagram 101586 A ANSWER C.03 (2.40) Emergency generator starts (when 1 uf 3 phases reaches 310 VAC) [0.6]
Automatic transfer switch loads EG when output voltage is high enough (400 VAC) [0.63 Auto transfer of load back to normal supply (normal seeking) EO.63 Emergency Diesel is secured automatically CO.6]
REFERENCE 054:RM-08-2 and 3
G:__GE[gB06_DEEB@ll@_Gtj@BQGlEBlSilGS PAGE 1 E.
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ANSWERS -- UNION CARDIDE COR /03/27-SILK, . . .
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ANSWE;R C.04 (2.00) No LO.13 The 15 call for the Reg Rod to be no greater than O.60% delta-K/K EO.4 The purpose of this is, in the event of a malfunction in the automatic system, there would be insufficient reactivity in the Reg Rod to go prompt critical EO.5 To change the worth of the Reg Rod it could be relocated in the core in an area of less f l u:1 EO.5] or fuel could be removed from around the e::ieting Reg Rod 1ocation [O.5 REFERENCE * L'UI 6 h) ' ' ' '
' YJ ' '
Ci nti chem E::am Bani:: me kg% j m f t h ,,, . ,_ h, y w 4.c, w l ,
TS 3.3.2 pg. B dn 7 AE5MER 5 (1.40)
~
higher pool t.empt rature ( wrtr or s are directly above the core) [0.73 Erratic period and N1 level indications ( ut ing) [0.73 or noisc -
,
REFERENCE /([du T/S pg 20
D __10SIByMEUIS_6ED_COUISD65 PnbE 19
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, . . .
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ANSWE,R D.01 (2.00)
U Power > 100 KW E O .,M 3 7 Reposition the detectors to match thermal power [ 0.,5 ) NI's are affected by rod or sample shadowing E O.72]
-' n ri c2nnot_ accurately detect II: chirtc in the [crr EO.53 REFERENCE 054: RM-03-6 TS p. 9 RM-04-20 RS-14 January 1986 RO Requalification E::am: ANSWER D.02 (1.60) all reverses [ M <mi y Nvcese s ,s.lf b4 co e gI4 d' fu' C M~ manual movement of reg rod manual button on console loss of power to console (0.4 pts each)
REFERENCE f Union Carbide Nuclear Reactor: Duestion Bank D.1M (modified),
Training Manual, p. D-2 ANSWER D.03 (1.00) f r otn under compensated to over compensate [0.53 E0.53 REFERENCE Union Carbide Nuclear Reactor: Training Manual, C-4 and 5 3 D-1 RM-03-3
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u . . . . .
D. __INSIGUt!EUIS,,0ND_CQUIBOLS
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F' AGE 20
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ANSWERS -- UNION CARDIDE COR /03/27-SILK, . . .
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ANSWER D.04 (1.60)
< 2 CPS
>9800 CPS Fission chamber movement LCR recorder off 30 second period LCR < 0.001 1og n 30 second period log n ' '. ~' 1og 4 Guide tube 1ift L. C f 2 .b c .:Isht6'C Red d-i"e toggle cm tch (or - oft c'ei t c M (0.2 pts each)
REFERENCE Ci nti chem E::am Bank: D.1 p5-ce-1 ANSWER D.05 (1.00)
Since both are dependent on core flow (0. 5) there is a time delay thus preventing use as a safety channel where response is imperative (0.5).
REFERENCE Ci nti chem E:< am Dank : D.3 ANSWER D.06 (1.00)
Reading would be higher [0.53 due to the higher delta p across the orifice EO.5]
REFERENCE T/S pg. 28 ANSWER D.07 ( .50)
False REFERENCE T/S pg. 28 i a
E __g8EEIY_OUD_EMERGENGy_SY@ led 5 PAGE 2)
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, e 4 =
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( , .. 1 te.:< l .
,; y, ;. (y .. n .!
_fY ANSWER E.01 (1.50) .
5. (rt<.<*f. +1s I% % power scram on UICs f/, (en3./c [ 7 P 't ~d second period scram from log n' amp >2nL scram when primary pump is off >X2nL f1ow scram with f1ow <2000 gpm O./67 >2nL scram with f1apper open W + pts each)
REFERENCE
.M Union Carbide Nuc l ear Reactor: Duestior. Ban * D.M , TS-09-10, RM-04-2, Training Manual, p. D-4 AN5WER E.02 (1.50)
The reactor would be cooled by the emergency core spray which directs a spray of water onto the core EO.5 It is supplied by the municipal water supply E0.53 and is initiated by manually opening a valve located outside the upper level air lack EO.5 REFERENCE Union Carbide Nuclear Reactor: Question Bank E.19, T5-29 (5.4.3), Figure B- ANSWER E.03 ( .50)
<95 [+0.53 REFERENCE Union Carbide Nuclear Reactor: RS-31- ANSWER E.04 (1.60)
Increased air activity as recor ded on the CAMS Increase on the N-16 recorder Arca r adi ati on monitor alarms Stack monitor system alarms E:: cur st on moni t or alarms (0.4 pts each)
[1.6 pts ma:: 3
'E __SOEEIy_QND_EDE6GEUCy_SYSlEd PAGE 22
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ANSWERS -- UNION CARDIDE COR /03/27-SILK, e-( u
, a REFERENCE Cintichem Exam Bank: E.1 ;AF
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ANSWER E.05 (2.00) Rad level of 5 R/hr detected by one of the two bridge excursion monitorc (0.5) and commericial power failure (0.5) Yes (0.5). Any initiation of the evacuation sequence requires an immediate shutdown (0.5).
REFERENCE Cintichem Exam Bank: E. January 1986 RO Requalification Exam: ANSWER E.06 (1.40)
Main dampers would stay shut [0.353 and the main exhaust fan would remain off [0.353 because of the manual reset relay [0.7]
REFERENCE EP-58
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E __SION9689_6UD,EMEB@ENCY_QEE80IlN@_E6QCEQUBES PAGE 25
ANSWERS -- UNION CARBIDE COR /03/27-51LK, e <. s,
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ANSWER F.01 (1.50)
Count rate channel is operating and on scale [0.75]
Console is attended by licensed operator [0.75]
REFERENCE 054:RM-09-1 ANSWER F.02 (1.50)
Remove three fuel elements from outside the core [0.753 and conduct a criticality check. EO.75]
REFERENCE 054:RM-10-5 ANSWER F.03 (2.40) . . .f ' p i, .- z . - u . c b , ; e e T / r t .t [ # N l i" i
'
f * ' ' y., . M'en I Q ts.w :. w Y, '
Shutdown EO.43 since saf ety f eature has failed to operate (rod reverse at 2NL and 50% withdrawn) EO.4] Continue to operate EO.4] post signs on door and promptly attempt repatr.[0.43 Shutdown [0.47 Fan is required for operation. EO.43 REFERENCE 054:RM-04-4 to 5 EP-03-3 RM-07-1
'-
g;_,f ANSWER F.04 (1.80) Loss of the water seal in the canal [0.6] The opening of both doors, either in the personnel airlocks or the equipment airloct5 [0.63 Inability of the emergency e::haust system to perform its required function EO.63 REFERENCE Union Carbide Nut 1 ear Reattor: RM-04- 'Ez__EI6dDOBD_8Up_EUEBgEUGY_9EEBOIIN@_ESQgEDUSES PAGE 24
' ANSWERS -- UNION CARBIDE COR /03/27-SILK, D.
o ., %
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ANSWER F.05 (1.50)
1. Commercial power failures E0.5] False signals which in the opinion of the senior operator have been properly verifie [0.53
- Intentional shutdowns which are not related to the safety of the reacto CO.53 REFERENCE RM-03-6
,
G___ BOD 10IlgN_CQNIBQL_6ND_S@FEIY PAGE 25
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, .
h., a +
. r ANSWEiR G.01 (1.00) Unshielded radiati on level ; 500 mr/hr at 1 ft. [0.53 yes E0.53 REFERENCE 054: RM-11-2,3 ANSWER G.02 (1.70)
wf f g.,g y d -
"y R /,esi,Y c N
[0.53
, Quarterly limit 1.25 R 1 time = (1.25 R / 4.6 R/hr) X 60 min /hr .C [ -1 5 ) c- d c'e ' - * b ' I l ,
= 16.3 min [0.5] No. [0.2] G. M. tubes do not measure beta dose rate and so would not provide an accurate indication of radiation levels. [0.53 ~ -
- % 4 /sn'3 }. < k iis !<!,
REFERENCE
"/ L~ M'*f ~ l. /;l h Y'u '~ y S-6 ht r r- '
1OCFR20.101 Cintichem Exam Bank: G.14 (modified)
ANSWER G.03 (1.30)
Change fi1ter elements Passing backwash and regener ar,t solution through the resin beds Replacing resins Working in HUT area (0.5 pts each)
REFERENCE 054: RM-06-4 ANSWER G.04 (1.00)
any operations E0.5] or HP personnel LO.5]
REFERENCE RM-07-3 E P- c 3 - C 3
0:_ _B 6210I19ti_ C Q NIB Q L _Q N D _ S O E EIY PAGE 'o t
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ANSWERS -- UNION CARBIDE COR /03/27-SILK, a m-
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ANSWER G.05 (1.60)
Unex pl ai nted al arm of 2 or more area monitors 00.53 Une::plained alarm of both reactor building CAM's in any combination EO.53 Unexplained alarm of one or more building or canal radiation alarms LO.3]
simaltaneously or consequtively with a stack alarm CO.3]
REFERENCE EP-03-3 ()NSWER G.06 (1.60) [0.43 searched or left with receptionist [0.43 one or two sets of pocket dosimeters and a film badge CO.4] Yes, with special arrangement with the HP superviso LO.4]
REFERENCE EF-14 section .
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Water. Parameters Miscellaneous Conversions 1 Curie - 3.7 >. 10 dps
) gallon - 34 > i W,
! c.:l lon . 72 liters 1 kg = 2.?1 lbs
= ' oa l );m s I hp 2 . 5.- x 10 Btn/hr
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= 970 Blu/lbm Degrees i = (1.8 x Degrees C) + 32 Heat of Vaporization I inch - 2.54 centimeters.,
lleat of lusion - 144 Blu/lbm g . 32.174 ft lbm/lbf-sec'
1 Atm = 14./ psio = 79.9 in lig
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U. S. NUCLEAR REGULATORY COMMISSION
- ' SENIOR REACTOR OPERATOR REDUALIFICATION EXAMINATION FACILITY: _UNigN_CORBIDE_COREt_____
.
REACTOR TYPE: _ TEST ____________________
DATE ADMINISTERED: _gZ/g3f2Z________________
EXAMINER: _SILLG_D.________________
CANDIDATE: __M f_ ____________
INSIBUCIlgNS_Ig_CONDIDgIEi Read the attached instruction page carefull This examination replaces the current cycle facility administered requalification examinatio Retraining requirements for failure of this examination are the same as for failure of a requalification examination prepared and admi ni ster ed by your training staf Points for each question are indicated in parentheses after the questio The passing grade requires at least 70%
in each category and a final grade of at least 70%. Examination papert will be picked up four (4) hours after the examination start % OF CATEGORY % OF CANDIDATE'S CATEGORY
__Y86UE_ _IQI6L ___SCOBE___ _yg6UE__ ______________C8IEGQBY_____________
_12129__ _29 90 ___________ ________ REACTOR THEORY
_12t99__ _29199 ___________ ________ RADIOACTIVE MATERIALS HANDLING DISPOSAL AND HAZARDS
_12tgg__ _29 99 ___________ ________ SPECIFIC OPERATING CHARACTERISTICS
_12t99__ _29 99 ___________ ________ FUEL HANDLING AND CORE PARAMETERS
________ ADMINISTRATIVE PROCEDURES,
_12t99__ _29399 ___________
CONDITIONS AND LIMITATIONS
_69tgg__ ___________ ________% Totals Final Grade All work done on this examination is my ow I have neither given nor received ai __--_________________________- _---
Candidate's Signature
_
s t NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS Dur-i ng the ac'1mi n i st r a t i on of this examination the following rules apply: Cheating on the examination means an automatic den 1al of your appl i cat i on and could result in more severe penaltie . Restroom trips ar e 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 gnly 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 necessar y) . Use only the paper provided for answer . Print your name in the upper right-hand corner of the first page of ea section of the answer shee . Consecutively number each answer sheet, write "End of Category __" as appropriate, start each category on a new page, write gnly 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 three lines between each answe . Separate anbwer sheets from pad and place finished answer sheets face down on your desk or tabl . Use abbrevi ations 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 no . Partial credit may be give Therefore, ANSWER ALL PARTS OF THE QUESTION AND DO NOT LEAVE ANY ANSWER BLAN . If parts 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 indicates that the work is your own and you have not received or been given assistance in completing the examination. This must be done after the examination has been complete e 1 18. When you, complete your c:: ami nat i on , you shall Assemble your examination as f ollows:
(1) Exam questions on to .
(2) Exam aids - figures, tables, et (3) Answer pages including figures which are part of the answer, Turn in your copy of the examination and all pages used to answer the examination question Turn in all scrap paper and the balance of the paper that you did not use for answering the question Leave the examination area, as defined by the examine If after leaving, you are found in this area while the examination is still in progress, your license may be denied or revoke PAGE 2
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Uz__6E6CIOB_IMEO82 e i
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OUESTION H.Ol (1.50)
a, ,The reactor is started up and K-excess is measured to be 6.0% delta L per If the pool temperature had been 10 degrees F higher when the K-encess measurement was made, estimate what K-encess would be and enplain why it change [1.03 At what reacti vi ty value would the reactor be critical on prompt neutrons alone? [0.51 OUESTION H.02 (2.00)
Technical Specifications limit K-excess to a maximum of 10.0% delta F/k (stall) and 8.2% delta k/L (open pool). What is the basis for these limits and why must the open pool value for K-excess be smaller in order to meet the basis?
DUESTION H.03 ( .85)
Would an inaccurately low reading for coolant flow rate during the procedure to calibrate the Power Level normal channel s result in actual reactrr power being higher or lower at t h t; moment of a high power scram? g k , ,g DUESTION H.04 (1.50)
What effect would an increase of 10F in pool water temperature have on actual reactor power assuming the rod control system is in the Linear N mode? Explai QUESTION H.05 (1.50)
Explain how and why the peak / average ther mal flux ratio would change if a steel canister (void can) were placed nent to the core and power were held constan (***** CATEGORY H CON 11NUED ON NEXT PAGE *****)
U __BEGCIOB_lHEgBY PAGE L.
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QUESTION H.06 (2.40)
Co,n s i der the f ollowing information:
Actual reactivity present in the core is minus 4% delta-K/K Count rate channel indicates 100 CPS Several hours later, rods are being pulled for a startup. The rods add 0.01 delta-K/K of reactivity and the new count rate is 196 CPS. However, since the initial count rate, nenon has made a reactivity contributio CALCULATE the reactivity contribution made by Meno QUESTION H.07 ( .75)
Which one of the following descriptions best supports the reason why Xenon reactivity increases sharply after a trip f oll owi ng 1000 hr of operation at 100% power ?
A) Xenon decays less rapidly due to a reduction in the neutron flu B) Iodine half-life is much shorter than Xenon hal f -li f C) Iodine production is greatly reduced and Xenon production is greatly increased due to the reduction in neutron f l u:: .
D) Due to reduced neutron absorption, Iodine concentration increases, and Xenon decays directly from Iodine, thus Xenon increase QUESTION H.08 (1.50)
Explain why the reactor must be made subcritical pr i or to moving the fission chamber if below Log-N confidenc (***** END OF CATEGORY H +++**)
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PAGE 4 Iz__BBD190CIIVE_UGIEB1065_UGUDLING_DISEQS@6_6ND_06Z66DS 9 9
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QUESTION 1.01 (2.40)
Tte label on a Cobalt-60 source is dated December 196 t According to the label, the source is 50 curie You must shield this source with steel such that a High Radiati on Area (as defined in 10CFR20) will not exist further than five feet from the source. Assuming that the attenuation coefficient, u, for steel is 0.31 cm-1, how thick should the steel shield be7 Show all your wor Assume a half-life of 5.3 years for Co-6 QUESTION I.02 (1.00)
a.If a reactor operator is assisting an e:: p er i men t er in the handling of a previously stored sampl e, and is able to remove the sampl e from the pool and perform all the necessary monitoring, under what conditions would he be required to obtain H.P. coverage prior to transfering the sample into a shielded cantasner? [0.53 b.If the above conditions were NOT met, and the e::perimenter wanted to open the sample, in HP coverage required? 00.53 OUESTION I.03 (2.40)
After an incident, a curvey is made of the affected area with a Cutie-Pl The window open indication is 6.4 R/hr, window closed is 4.6 R/hr at 2 fee a. What in the Deta dose rate? State any assumption [0.63 b. How long can you remain in this area without e::c eed i ng your normal quarterl y whol e body limit? [1.03 c. Would a G. M. meter be used in this case? Why cr why not" [0.83 OUESTION I.04 (2.00)
What four process system maintenance tasks should have, by procedure, dirett health physics survei11 ante and are normal 1y reser ved for the day shift?
(***** CATEGORY 1 CONTINUED ON NEXT PAGE *****)
Iz__809198GIlyE_UBIEB196@_UQUDLINg_DigEgg86_00D_UQ10BDS PAGE S
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DUES 1 ION I.OS (1.00)
What, persons may author ize the use of emergency ventilation during conditions of high airborne activity when it appears advisable to evacuate the building?
OUESTION I.06 (1.60)
List the three alarm conditions which require immediate shutdown of the reattor and initiation of the evacuation sequenc QUESTION I.07 (1.60)
You have been assigned to escort a group of visitors through Building 1 and What is the maximum group size you alone can escort? How are visitors packages, handbags, etc. handled? What minimum dosimetry is required for the vi sitors? On visitor unexpectedly brings his 12 year old son. Under what conditions can the boy accompany his father on the tour? [0.4 each]
(***** END OF CATEGORY I *****)
Jz__SEEglElG_DEEBQIlN@_GUSB8GIEBl@llG5 PAGE 6 ;
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OUESTION J.01 (2.40)
The, reactivity of a sample placed in a neutron flun of IEE13 is measured to be 0.l*/.. What would you expect the reactivity of thi-s sample to be if you paced it in a core position where the neutron flux is 2.2EE13 and is it allowable to load the sample in the higher flux position? Explai QUESTION J 02 (2.40) Explain what will happen, in terms of the electrical system, if all normal power is los L1.23 What manual steps or automatic actions must occur to restore the normal electrical lineup after operation in the emergency lineup?[1.23 OUESTION J.03 (2.00)
LIST two precautions which must. be taken if the cooling tower fans are to be operated in the reverse directio QUESTION J.04 (2.00)
Following the loading of a new core configuration, the control rods are calibrated and the Regulating Rod is found to have a total worth of 0.61 percent delta-K/ Is this acceptable? Enplain why or why no What measures could you take to change the worth of the Regulating Rod?
QUESTION J.OS (1.20)
Li st sin of the interlockc that inhibit rod withdrawa QUESTION J.06 (2.00>
What five automatic act1ons wil1 immediately occur when the emergency ventilation system is initiated?
(***** END OF CATEGORY J *****)
Et__EUEL_U9Np61N9_GUD_CQOE_E8000ElEOS PAGE 7
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QUESTION K.01 (1.50; Whpt two conditions must be met pr i or to allowing maintenance on a com-ponent near the reactor core which could cause a reactivity change?
DUESTION K.02 (2.40)
What personnel are required to be present and where are they to be stationed for fuel manipulations within the core and near the core region?
DUESTION K.03 (1.50)
What actions, if any, need to be taken so that a fuel element can be loaded into a prevtously blocked center position?
DUESTION K.04 (2.40)
Observance of the required minimum shutdown margin is important in avold-Ing inadvertent criticality should one rod somehow be removed from the cor INDICATE whether or not this requirement is satisfied in the following case SHOW your wor The reactor is critical at low power (with no Xe-135) with the rods at 13.00 inches, and the highest worth nonsecured experiment is warth -0.4% delta M/ The reactor is at 5 MW with equilibrium xenon, with no e::per i men t , and with the gang at 15.20 inche Given in both cases: gang worth - 8.35%
13.00 - e:: cess reacti vi ty is 4.88%
15. 20 - e:-: cess reacti vi ty i s 1.30%
highest worth rod - 2.65%
power coefficient worth - O.35%
xenon worth - 3.5%
QUESTION K.05 (1.00)
E::pl ai n why a 1imit e:: i et s for fuel element burnu (***** CATEGORY L CONTINUED ON NEXT PAGE *****)
PAGE O b __E9E6_USNDblG@_SUD_QOBE_E888DEIEBS
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DUESTION K.06 (2.00)
During a fuel heridling oper ation, bubbles are observed coming from an element as it is withdrawn from the core. DESCRIBE your immediate ac t i otic . (2.0)
OUESTION K.07 (1.20) How many fuel elements may be removed from the safe storage of the fuel vault at one time for the purpose of core refueling? [0.43 Under what conditions may the Reactor building Crane be used to transfer an i nd i vi du al fuel element?
.
(**++* END OF CATEGORY K *****)
Lz__0901NJDIBOllyE_P69CEDU6ES2_CQNDillgNQ_ONp_LldlIBI190s FAGE 9 o . s
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QUESTION L.01 (2.40)
Ir)di cat e whether each of the f ol l owi ng si tt.ati ons woul d require immediate shutdown of the reactor. Consider each situation separately and justify your answer (for a shutdown) or explain your actions (if shutdown 2s not required). Rods are being withdrawn and are at 10 inches while raising power above 2NL on a 45 sec period, The personnel airlock interlocks become inc perabl The normal reactor building exhaust fan trips and cannot be restarte QUESTION L.02 (2.10)
Who may authori:e each of the following: Reactor restart following a shut down which was required because the depth of water in the canal reached 9 feet. The depth of water in the canal is now 12 fee Changes in scheduled power level for the convenience of an enperimenter, Permission to operat e the reactor in the pool positio Completion of only selected portions of startup check lists for a startup which is to occur within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of the previous shutdow QUESTION L.03 (1.50)
An operator informs you that he has increased the set point on one of the area monitors because it was continuously alarmin Can this be an acceptable course of action? EXPLAI OUESTION L.04 (1,80)
LIST the four events that require immediate NRC notificatio (***** CATEGORY L CONTINUCD ON NEXT PAGE *****)
b c _ _69 TIS ISIB011ME _EB Q C E pub E S 2_ C Q U p111gg S _8U D_61dll8Ilg g s PAGE 10 e . , *
QUESTION L.OS (1.80)
WHAT three conditions constitute a violation uf reactor building containment?
DUESTION L.06 (1.20) What are the potential consequences of operating with fewer than thirty fuel elements? How are control el emen t s considered in this total?
OUESTION L.07 (1.20)
Facility rules require notification of the Senior Operator in the event of a startup following on unscheduled or unplanned shutdown. The senior operator need not be "in attendance" for three conditions. What are they?
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(***** END OF CATEGORY L *****)
(*+++,**++*+++ END OF EXAMINATION ***************)
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.
.
.
- ----.-------.........--.--..........-- -----. ......._-- -_.----....--_ ..
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E00ATI0ff FORMULA AND PARAMETER SHEET
.......-..........-------........------ .....----------... - -----.--,-...--
.
. .
Where my = mp
,
,,
'
.(density)3(velocity)3(area)3 = (density)2(vel city)2(arca)2
? (it
'
PE = mgh PE3 + KE3 tP33V = PE 2+KE2+P22 v where V = specific KE = mv2 volume P = pressure
.-----....--........................--......--..........----......------_-
Q = mcp(Tout -T;g) Q = UA (T ave -Tstm) Q = m(h3 -h2)
q
- -----....--------.:.............---......--.....----....---------....--._
t/T T=
- .= (0 ~ #)
P = Po 10(SUR)(t)- p,p o SUR = 26.06 1 p pXggg
~~'
- ... ......--- --....
................------........---...--.....--......--- ..
delta K = (Keff-1). CR3 (1-Keff1)- = CR2 (I-E,,eff2) CR = S/(1-Keff)
s (1-Keff) x 100% -1 (1-Keffl) SDM = Aeff = 0.08 sec K
M = (1-L,e ff2) eff
--....---------- .---....----- ..--........---- ........ --................
A e (decay constant)x(t)
-
p decay constant = Int (2) = 0.693i A =
1/2 1/2
---......... -----..--...........--........--.........---......-----...
Water Parameters Miscellaneous Conversions
1 Curie = 3.7 x 10 dps 1 gallon = 8.343 lbs 1 gallon = 3.78 liters 1 kg = 2.21 lbs I ft = 7.48 gallons I hp = 2.54 x 10 Btu /hr i 6 3 1 MW = 3.41 x 10 Btu /hr Density = 62.4 lbc/ft Density = 1 gm/cm# 1 Btu = 778 ft-lbf Heat of Vaporization = 970 Btullbm Degrees F = (1.8 x Degrees C) + 32 Heat of Fusion = 144 Btu /lbm 1 inch = 2.54 centimeters 2 1 Atm = 14.7 psia = 29.9 in Hg g = 32.174 ft-lbm/lbf-sec 1 ft H 2O = 0.4335 lbf/i ......------...... --...--....--.....-----------..- - - - - --
--
PAGE 11 Dz__6EOGIOB_IHEDBX
, i fgNSWERS -- UNION CARBIDE COR /03/27-SILK, .
.
ANSWlih H.01 (1.50) K-e::c ess = 6. 0% - (O.OO44%/deg F)(10 deg F) = 5.956% [0.53 K-excess is smaller because the negative steady state temp coefficent has added negative reactivit [0.53 +0.81% delta k/k +or- 0.01% [0.53 REFERENCE DS-01-1 ,
ANSWER H.02 (2.00)
Provides f or at least 0.5% [0.53 negative shutdown margin after scram assuming man worth rod stuck out of core. [0.53 Moving the core from the pool to the stall has a positive reactivity effect (0.8%) [0.53 Thus if K-excess was greater than 8.2% in the pool, and the core was moved to the stall, the basis may not be me [0.53 hEFERENCE T/S ANSWER H.03 ( .85)
O=m dat Cp (Tout - Tin) LO.253 if m dot is low, Ocalc is low and actual thermal power is higher. [0.253 NIs are calibrated to Ocalc and will therefore read low. E0.253 Thus, actual reactor power will be HIGHER at the scram setpoint. [ 0.1[> 3
'
REFERENCE T/S pg. 9 and equation sheet provided
PAG ' H __8E6GI98_lHEQB ],; :. : ANSWERS -- UNION CARBIDE COR /03/27-SILK, ' .. :.
.ANSWG H.04 (1.50)
. .{is<. >m I 1 cA
'As temperature increases more' fast neutrons _ escape. NI's measurel'
fast neutrons. [O.753 Linear N-will i re ' - ci ; to maintain constant indicatedfpowert.253 Actual: reactor powerJwould-be lower. 00.53 REFERENCE 054: Nuclear Energy Training, Module 3.Rx' Ops, Unit ANSWE H.05- (1.50)-
.75~
The . ratio will increase 14r53 because the f l ux ' will-' increase in the center.of the core since the canister will not. reflect neutrons bac
to the periphery-of the core. 1G -5T 75'
~
-REFERENCE 054: RM-10-5-R.R. Burn 1984 Chapt 9 Intro to Nucl. Reac. Op .
ANSWER H.06 (2.40)
Rhol = (Keffl - 1)/Keff = -0.04 E.25]
Keffl = 1/((1 - '(-0.04)3 = 0.9615 CO.53 100(1 - 0.9615) = 196(1 - Keff2)
Keff2 = 0.9804 CO.53 Rho 2.=.(0.9804 - 1)/O.9804-= -0.02 E.253 Del ta Rho == Rho 2 - Rhol = -0. 02 - (-0. 04 ) = 0.02 EO.53 0.~ O 1 Delta K/K was from the rods therefore +0.01 Delta K/K was from Xenon EO.43 REFERENCE Cintichem E::am Bank: H.4, H.8, H.9 (modified)
R,B.,rn 119't - Cyp f 5' J,M EbDM~0P5 ANSWER H.07 ( .75)
. B ( 0. 5) ~
t REFERENCE
- eccet - nacq tc;;cr.
- : ,NcT : it.2) c. .st . c L ., . c,-
SF1 CRDS/OOO KS.33 L,2 /Iw)l~. f;. tu : <L _e '? 7
-
,
-
/ d
!
t
.
- ,
PAGE 13 U:__SEAGl98_lbEOBY
- * ANSWERS -- UNION CARBIDE COR /03/27-SILK, .
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i (,,u-/,,,el ne..fim ,,u,/p,p/,,,,f,
.
ANSWER H.OB (1.SO) n V
No change should be made to the reactivity of the core unl ess dependable power indication is available. E0.753 (Moving fission chamber changes the reactivity of the core.) Log-N below confidence indicates unreliable power level indication and fission chamber cannot provide accurate indication while being move %d LO.753 REFERENCE 054:RM-03-5
, - - . .
PAGE 14 1:__B09190CIIYE_MOIES1865_UONDLlOG_Di@PQS@b_@ND_UOl@BDS
. , AWSWERS -- Uti1ON CARDIDE COR /03/27-SILK, =
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ANSWE,R I.01 (2.40)
A = Ao exp ( .693 : t / 'i l / 2 ) ; t = 22.25 years T1/2 = 5.3 years A = 2.73 Ci EO.63 Dose rate at 1 ft = 6CEN = 6 (2. 73) (2. 5) (1 ) = 41-R/hr at 1 ft E0.63 Rn D**2 = r :- d**2 r = 41/25 = 1.64 R/hr at 5 f CO.63 I = Io exp (-u X); I = 0.1 R/hr lo = 1.64 R/hr X = 9.02 cm = 3.55 inches 00.63 REFERENCE Cintichem Exam Bank : I.13 CAF ANSWER I.02 (1.00) Uns>hielded radiation level e 500 sr.r/hr at 1 f CO.53 yes 00.53 REFERENCE 054: RM-11-2,.?
ANSWER I.03 (2.40) Beta rate = (open - closed) X Beta efficiency factor E0.33
= (6.4 - 4.6) X 10 = 18 R/hr CO.33 Quarterly limit 1.25 R 00.53 %
.
time = (1.25 R / 4.6 R/hr) X 60 min /hr h g i{ ,et, vf SS />6'I
= 16.3 min EO.53 g, yff -fg , a 4-d c7,, No. [0.33 G. M. tubes do not measure beta dose rate and so would not provide an accurate indication of radiation levels. [0.53 ,
or g G. M ftshe ecM < cdt-r nYe'_ in #4 T 4,y k a [t // ,
l REFERENCE 10CFR20.101 'j -
Ma r- ,v.4 t, + [ -- [// ,s.$;)
Cintichem Exam Bank: G.14 (modified)
"
1 __B89100CIlyE_M91EBl@65_d@Np61N@_plgPgg66_8Np_H818Spg PAGE 16
- ANSWERS -- UNION CARBIDE COR /03/27-SILK, .
=
ANSWEf< I.04 (2.00)
Change fi1ter elements Passing backwash and regenerant solution through the resin beds Replacing resins Working in HUT area [c-/ /.. ,- n. g_.c, 3 du,w s /y (0.5 pts each)
REFERENCE ib. c /c phy c i-- (<"> d -"sh< ++'e1'
/t.] k vd er.S e2 s 054: RM-06-4 Wo]l bv un r s'c%m .l ANSWER I.05 (1.00)
any operations LO.53 or HP personnel [0.5]
REFERENCE RM-07-3 ANSWER I.06 (1.60)
Unexplained alarm of 2 or more area snonitors EO.53 Unexplained alarm of both reactor building CAM's in any combination LO.5]
Une::pl ai ned alarm of one or more building or canal radiation alarms EO.3]
simaltaneously or consequtively with a stack alarm [O.33 REFERENCE EP-03-3 ANSWER I.07 (1.60) EO.43 searched or left with receptionist E0.4] one or two set s of pocket dosimeters and a film badge EO.4]
' Yes, with special arrangement with the HP supervise EO.43 REFERENCE EP-14 section PAGE I __SPECIElG_OPEB811NG_CU688GIEB1511C5
- * AHSWERS -- UNION CARBIDE COR /03/27-SILK, . .
ANSWER J.01 (2.40)
(2.2EE13/1EE13) squared = 4.8, 4. 8 : 0.1% delta-K/K =0.48% delta-K/K E1.03 This is allowable EO.43 because the maximum individual sample worth is 0.5% delta-K/K [1.03 REFERENCE January 1986 SRO Requalification Exam; TS 3.6.1 (3) pg. 13 ANSWER J.02 (2.40) Emergency generator starts (when 1 of 3 phases reaches 310 VAC) [0.63 Automatic transfer switch loads EG when output voltage is high
'
enough (400 VAC) [0.63 Auto transfer of load back to normal supply (normal seeki ng ) [0.63 Emergency Diesel is secured automatically EO.63 REFERENCE 054:RM-08-2 and 3 ANSWER J.03 (2.00) The cooling tower fans are not to be put in reverse mode while they are still turning in the-jc. . rd directio .
[1.03 x=.+n-6 The cooling tower fans shall not be operated in the reverse direct-ion for more than 30 minute E1.03 REFERENCE Union Carbide Nuclear Reactor: RM-06- Jc___@EECIElG_9EEB811tJ@_Ctj888GIEBigIICS PAGE 17 s e AWSWERS - UNION CARBIDE COR /03/27-SILK, ,
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ANSWE,R J.04 (2.00) No CO.13 The TS call for the Reg Rod to be no greater than O.60% delta-K/K
[O.4 The purpose of this is, in the event of a malfunction in the automatic system, there would be insufficient reactivity in the Reg Rod to go prompt critical CO.5 To change the worth of the Reg Rod it could be relocated in the core in an ama of less flun EO.5] or fuel could be removed from around the eniu ing Reg Rod location EO.D].
&, *
' z jy ' . t. : c'p h :l ~
'I
'h r: ' -'" d REFERENCE ,
Cintichem Enam Bank: "'M 4 51 -/c re - .,'/15 h 'l
'
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,
TS 3.3.2 pg. 8 ANSWER J.05 (1.20)
< 2 CPS
> 9800 CPS Fission chambef movement LCR recorder off 30 sec periad LCR s O.001 1og n -
30 sec period log n C ^ <"41 ing n-guide tube lift ,j
~-
.cd d '- 4 u n & ne'n1 n s wi_Lc14 f nt4- =-_o Li-s.wi.tc h ) L. C C, /, s i'~~ - REFERENCE / '
/' -
DS-02-1 ANSWER J.06 (2.00)
i RB supply fans shutdown Pool sweep damper clones Holdup tank vent line and air purge valves close Al1 supply dampers c1ose Beam tube enhaust fan shuts down EO.4 each]
REFERENCE C & *' W J O L '" "
054:RM-07-4
r-PAGE 1E lj;__FUE6_UQUDLING_OUD_gDSE_E@R@MEIEBS
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'A$SWERS -
UNION CARBIDE COR /03/27-SILK, . *
ANSWER K.01 (1.50)
Count rate channel is operating and on scale EO.753 Console is attended by licensed operator 00.753 REFERENCE 054:RM-09-1 ANSWER K.02 (2.40)
Minimum of two licensed operators EO.63 SRO in direct supervison EO.63
- 0ne in Control (monitoring count rate channel) EO.63 P On e -FHe on bridge EO.63 REFERENCE 054:RM-10-6 ANSWER K.03 (1.50)
Remove three fuel elements from outside the core EO.753 and conduct a criticality c h ec i: . [0.753 REFERENCE 054:RM-10-5
. . . .. . . - - - . - .
Ka__EUEL_d@NDLING_OND_COBE_E888MEIEBS PAGE 19
- : * AMSWERS -- UNION CARBIDE. COR .
-87/03/27-SILK, ,g a
_ 1
- ANSWER K.04 - (2.40)-
.
~
Minimum shutdown margin is 0.5% delta K/K [0.43
, At 13.OO excess reactivity is 4.88%
"
Xenon and-power' coefficient are O-Highest worth rod fully withdrawn is 2.65%
Nonsecured experiment-is O.4%
8.35-4.88-0-2.65-0.4 = .42%
-Not OK--less than minimum shutdown margin [1.0]
b.- At 15.20 e:: cess reacti vi ty i s 1.30%
Xenon power-coefficient are 3.5% and 0.35%'respectively Highest worth rod fully withdrawn is 2.65%
Nonsecured experiment is 0 8.'35-1.30-3.5-0.35-2.65-0 = 0.55'
OK--shutdown margin satisfied L1.03 REFERENCE-Union Carbide Nuclear Reactor: Duestion Bank J.10 (modified), .
TS pg.'.7 i - ANSWER K.05 (1.00)
, The probability for a fuel el ement - f ailure increases [0.53 and
'
the consequences of a failure increase EO.5 REFERENCE Jan 1986 SRO Requal Exam: T/S 3.7.6
.
ANSWER K.06 (2.00)
Lower the element back into position leaving the]ool attached 5Y7 Leave the bridge and leave the building dnd initiate l
i E v.~i s the evacuation sequence [+0.5 Giver cuf 4-i c i ent - t i me-f or-the--
bubb1es to br.eak the--sur-face, ther r cer+t er the bui1di v; =d t r ';
te detr -inr ii = h az a r d wa s p r esen t .-14-notrto-y t e d e t er-ai ne-i the ceur If , - ha: ard-waru-present r- use the amergency call
list and notJAy the-necessary per-sens of t h" M t ' 's + i "" [+0 -
! REFERENCE it
!- Union Carbide Nuclear Reactor: Question Bank K.J4, RM-10-7,
RM-04-11.
,
t
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L
-- ..~.-,--m,- ,,,v.s, ---,.--+-..wo,~,+ ,rm-,v- -m-m w-~ , , - ~ ~ - . , , , - - , --e-w,,em----m,- -r----rw--,---nr- ,
,
-
f3t__ eye 6_UQUD6100_QUD_COBE_EQBOUEIEBS PAGE 20
, g AUSWERS -- UNION CARBIDE COR /03/27-SILK, *
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ANSWE,R K.07 (1.20) Two [0.43 Only within the confines of the pool and stall [O.43 and provided the element is 1atched on a special fuel handling tool. [0.4J REFERENCE RM-10-8
PAGE 21 6:__6DUINIS18611M_EROCEDUEE h_CONDlllONS_6ND_610ll6IlONS
- * AMSWERS -- UNION CARBIDE COR /03/27-SILK, .
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ANSWER L.01 (2.40) n .-, s 3 , , c,. . I, , . ,g <r,/,,. // n ./;
P ,, L , ...-<.#
g.,-
,
-l I,.'
'
l-i s -
.Y . . < p' c./ Shutdown [0.43 since safety feature has f ailed to operate (rod reverse at 2NL and 50% withdrawn) [0.43 Continue to operate [0.43 post signs on door and promptly attempt repair.[O.43 Shutdown [0.43 Fan is required for operation. [0.43 REFERENCE 054:RM-04-4 to 5 EP-03-3 RM-07-1 RM-03-T ANSWER L.02 (2.10)
g ,. .: c .: ~. - -, a l' ' ,'
, Level 2 authority[0.33 or designated alternates [0.33 Senior Reactor Operator [0.53 Nuclear Safeguards Cornmi t t ee [0.53 Senior Reactor Operator [0.53 REFERENCE 054:TS p. 37 RM-03-6 RM-03-1 RM-03-7 ANSWER L.03 (1.50)
+
The action is acceptable [ 0. /. ] as long as the reactor operator properly 1ogged the alarm and change [0.33, ""0 1 # 1ed n ORO Y tOOn ?' P O E s itd a-. cy, 9. .
-HC3 and the operator continued to monitor the actual radiation level en
[0./J and took steps to determine the cause and corrective action if '/ M" applicable [0 / '
REFERENCE Union Carbide Nuc1 ear Reactor: Question Bank L.14, RM-04-04, EP-O~, RM-09- _
6:__0D01NIGIB811yE_PBOCEDUBES3 _CONQlllONS_@NQ_61dlI@llQNS Pf4GE 22 c g 4pSWERS -- UNION CARBILE COR /03/27-SILK, ,
ANSWER L.04 (1.80) Enposure of any individual to 25 rem or exposure of skin to 150 rom or any entremity to 375 rem Release of radioactive material in excess of 5000 times the limit specified in Appendi:, B, if averaged over a 24 hr period A loss of one operating week Damage in excess of 1200,000 E0.45 each]
REFERENCE Uni on Carbide Nuclear Reactor: Duestion Bank 1.16, 10EFR2O Part 403, TS pg. 3G - Section 6. ANSWER L.05 (1.80) Loss of the water seal in the canal [0.63 The opening of both doors, either in the personnel airlocks or the equipment airlocks E0.6] Inabi1ity of the emergeracy enhaust system to perfarm its required function EO.6]
REFERENCE Union Carbide Nuclear Reactor : RM-04- ANSWER L.06 (1.20)
S Exceeding the peal to aver age ilun 1imit (3.3) E O ./,3
and possibly causing a fuel cladding failur [0.4] The control elements couret as one-half of a standard element. EU.23 REFERENCE T/S 3.7.2 l
l l
6.__0DDINISIB@llyE_BBQCEDUBES 3 _CQNDlligNE_6ND_61dllOllOU$
PAGE 23 0 4 DNSWERS -- UNION CARDIDE COR /03/27-SILK, .
ANSWER L.07 (1.2O)
1. Commercial power failures LO.43 False signals which in the opinion of the senior operator have been properly verifie [0.43 Intentional shutdowns which are not related to the safety of the reacto [O.43 REFERCNCE RM-03-6
.
, ,
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g R/L = Gm/d * (d m .
,,j_. - g 4.~ M h A .--.-------._---..._--..---...._-__-------_...--------_--____._-_-
EQUAT10N FORMutA AND PARAMETER SHfET
.--- -- - ------- ----------- ------ ----------------- ...----
.
'
Where mj = m2 (density)3 (velocity))(area)3 = (density)2(velocity)2(area)2
- ------- --------- -- -----------
where V = specific KE = mv" 7 PE = mgh PEg + KEg+P)Vj = PE2 *KI2+P22 v volume P = pressure
-------------------------------..... ..--------------------
.
Q = mcp(Tout -T.in) Q = UA (T ave -Istm) Q = m(b1 -h2)
~ ---------------------- ------------- ..... ------------------------- -------
b
'
~ #) m (/! - p)
P = P010(SUR)(t) P = P0 et /T SUR = 26.06i T=
P
..
P k eff
.
..............---- -------- -.
delta K = (K eff -1) 9 CR)(1-Keffl) = CR (1-K- eff2),
CR = S/(1-Keff)
(1-Keff) x 100* -1 M=
(1-Keffl) - SDH = Xcff = 0.08 sec K,e f f ( 1 - L.ef12)
. ... ---------------------------------------------------- ......
A e (decay constant)x(t)
-
decay constant = Int (2) = 0.693 A =
t 1 o 1/2 1/2
.---------------- ............... --- - ---- --------.-----------
Water Parameters Miscellaneous Conversions
1 Curie - 3.7 x 10 dps 1 gallon = 8.345 lbs 1 gallon = 3.78 liters 1 kg = 2.21 lbs I ft c 7.4S gallons I hp r 2.54 x 10 Btu /hr Density - 62.4 lha/ft 1 MW = 3.41 x 10(' Blu/hr hensity = 1 gm/cm# 1 Blu = 778 ft-lbf Heat of Vaporization = 970 Blu/lbm Degrees f & (1.8 x Degrees C) + 32 I inch c 2.54 centimeters, Heat of lusion = 144 Blu/lbm 1 Atm c 14.7 psia s 29.9 in lig 9 32.174 ft-lbm/lbf-sec'
I f! H;,0 0.4335 lbf/i .. ---............----- -----..---- --- --------- - -
_
-a