ML030870885

Fax, Krohn to Kunowski, Ops Notebook Entries to Address 11/22/2002 Emergent AFW Issues

ML030870885
Person / Time
Site:	Point Beach
Issue date:	11/25/2002
From:	Paul Krohn NRC/RGN-III
To:	Michael Kunowski NRC/RGN-III
References
FOIA/PA-2003-0094
Download: ML030870885 (12)

Text

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NRC FORM 398 (RIlI)

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?n':nt Brat.n Nuc.t ar Plain OPERATIONS NOTEBOOK FILE:

SUBJECT:

AFW Rec:,rc. ,th Los. of D-0.

See attached CAP regarding issue associatcd %vth Loss of Bus D-01 and mueffect on AFW Rccirc flow

- SI Approved By: R.Harrsch Place in Section:

Placed in Notebook: 11/21/02 Remove By: 12a 1/02 Date W~e Schedule for Removal: DSS Acknovxleogement Night Orders: 4 days or less Crew A - U C Operational Information: 31 days or less Crew B:

Significant Events: 31 days or less Crew C:

Industrial Safety: 31 days or less Crew D:

Administrative: 31 days or less Crew E:

Operational Experience: 31 days or less Crew F: OA f/ j Modifications: 31 days or less Miscellaneous: 31 days or less Request for Data: Until data is gathered U *e i¶1 frcrrccg OM 3.13 PBF-2OI5 Rcmson 9 04/09/01 KN321tIOd P:LEV*SSLOZ6 9P :60 EBOOIS/II/

- -- C-HGE. O--R-Y k-Lc STATE CHANGE HJSTORY I,' tite .9 AR Pre-Screen LZ 1 *2G22 2 28 33 "A, Cwn-2r (Non-,i bi CLINT CAESC-E= -M SECTION 1 Activity Request Id: CAP030209 Activity Type: CAP Submit Date- 11121"2002 228 33 Ov 0 One Line

Description:

Loss of 125V0C 5--s 0-01 Could MaKe Three ALW Dumps Inoperable 0 Detailed Description 11121/2002 2:28 33 PM - CLINT ORESCHER As part of researching a solution for the issues as.ociaTed with Ihe auxiliary !eeodcator(AFW) pump recirculation %,alves.I discovered that the recirculation valves lot both turfl",e-duiven AFW pumps (1AF-4002 and 2AF-4002) and Ihe control power for molor.dnven AFW pump P.

38A are supplied from 125VDC bus 001 (Valve 1AF-4002 and the P-38A contrat circuit are powered from 0 11 and valve 2AF-4002 ,s powered Irom D12) This was evaluated to check if the AFW system would continue to meet its design basis requirement to supply 200 gpm per unit followirng a low-low level signal associated with a design basis accident or event A single failure of equipment important to safety must also be considered when evaluating 0fa system will continue to meet it design basis requirements following a design basis accxjdnt or event.

Since the loss of D01 makes the fail closed recirculation valves on 1P-29 and 2P-99 go closed.

it has been concluded that Ihe loss of 001 could make 1 P-29, 2P-29 and P-38A inoperable, not allowing the 200 gpm per unit value to be met.

11/21/2002 3:08:39 PM - RON HARPER:

The loss of Bus D-01 would cause the recirculation valved for 1P-29, 2P-29 and P-38A to fail shut, thus challenging their ability to provide a reliable source of AFW to the steam, generators.

Initiator: DRESCHER. CLINT Initiator Department: EDEP Engineering Design Electrcal PB 4' Date/Time of Discovery: 11/21/2002 1:16"34 PM Datef/Tme of Occurrence: 1121/2002 116:34 PM Identified By: Site-identifled System: AF PB Equipment # (1st): P-029 PBE Equipment Type (1st): 9 STG CENT Equipment # (2nd): P-038A PE) Equipment Type (2nd): CENTRIFUGAL Equipment 4 (3rd): (None) Equipment Type (3rd): (None)

Site/Unit: Point Beach - Common Why did this occur?: 11/21/2002 2:28:33 PM - CLINT DRESCHER:

Unknown.

Immediate Action Taken: 11/21t2002 2:28:33 PM - CLINT DRESCHER:

Initiated this action request Notification of engineenng supervisor and operations.

11/21/2002 3:08:39 PM - RON HARPER.

Submitted 6perations Notebook entry to ensure information is provided to the ope ng crews Recommendations: 11121/2002 2:28:33 PM - CLINT DRESCHER:

(1) It appears that changing recirculation valves 1 AF-4002 and 2AF-4002 from fail l* sed to fail open will resolve this issue without having to change the power supplies of the valva. The turbine driven AFW pumps could supply the necessary 200 gpm with the recirculatil valves open from a single failure ;I (2) Revise ihe current operability determination (O0) associated with the recfrculati4 valves to encompass this issue and not allow closure of the 0D until this issue has been re.do4ea.

11/21/2002 3-08:39 PM - RON HARPER.

Revise OPR 000031 rev3 to address this issue. due in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Clint Drescher haslead hctps://nmc.rtrackonhine coff/tmirack/tmtrack.dli?IssuePa-e&Tableld= 1000&Recordld=284 1 }21/2002 VO8 3-)V d .. .LI JI0 d S..VLEV99L0Z6 9P:Ee Z00Z/5Z/T1

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reSp-nsil, D - I-- r.orr*'o!e: g OPP ref'sicr.

0 Notify Me During Eva*.. N 0 SRO Aev,cw Required?.

g SECTION 2 Operability Status" (Ncne) 0 Compensatory Actions- Y Basis for Operability: 1 1'2V2002 3 0B 39 PM - RON HArPPER.

Based on current ccrnpensatory actions being taken under CPR 000031 "e, 3. AFW systern rernaris operable but non-confor-n.rig in regards to the pumps recirculaticn 'lowpatrl I Unplanned TSAC Entry. N

• External Notification: 1 SECTION 3 Screened?. N 0 Significance Level: (None)

INPO OE Reqd?: N Potential MRFF?: N i QA/Nuclear Oversight?: N 0 Licensing Review?: N Good Catch/Well Doc'd?: NA SECTION 4 Inappropriate Action:

Process: (None) Activity: (None)

Human Error Typo: (None) Human Pert Fall Mode: (None)

Equip Failure Mode: (None) Process Fail Mode: (None)

Org/Mgt Failure Mode: (None) Q Group Causing Prob: (None)

Hot Buttons: (None)

SECTION 5 CAP Admin: P8NP CAP Admin Prescreener: (None)

• Project: Corrective Action Progranr (CAP)

• State: AR Pre-Screen

• Active/Inactive: Active

• Submitter: CLINT DRESCHER 040Owner: (None)

AR Type: Parent o Last Modified Date: 11t21/2002 3:08:31 PM o Last Modifier: RON HARPER 6!

• Last State Change Date: 11/21/2002 2-28:34 PM

• Last State Changer: CUNT DRESCHER *9 0 Close Date:

NUTRK ID:

• of Children: 0

References:

Update:

Prescroen Comments: I O Import Memo Field: I OPR Completed?: N https://nmc. ttrackon IIne.comLtmtrackcm track.di ?IssuePag e&Tabi eId= 1000&Recordld=21... I t21/2002 so V9dHrS.IdtLEt'S&LOZE 9V6 0 B2/GSUU ZOOB

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OLDACTIONNUM oub_'sid. 0 origlnal-ptoject_.d

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Site Point Beach Cartridge and Frame:

CHANGE HISTORY 11/21/2002 3:08:39 PM oy RON HARPER Detailed Descripttcn Changed From "Original Texir" To lAppended IThe loss of 2u 90-01 wouid cause the reorcuiator '*ed for 1 P-29.

2P.Z9 and P-38A to fail shut. M=u challenging thor ablity to preY'de a relfaole aouice of AFW 1o the steam gnenrator" System Changed From (None) To AF PB Equipment 0 (1st) Changed From (None) To P-029 P1 Equipment e (2nd) Changed From (None) To P-038A PB Immediale Action Taken Changed From lOnginal Textr To '(Appendod:} Sut*rmnd Operations Notebook entry to ensure rmon~tion is provided to the operating crewS I Recommendations Changed From TOriginal Textr To JAppendod.] Revise OPR 000031 rev 3 to address this I*4ue. due in g4 hours. Clnt Drescher has lead responsibility for completing OPR revision Compensatory Actions Changed From N To Y Basis for Operabtllty Changed From 'To "Appended:j Based on current compensatory actions being taken under OPR 009R31 rev 3.

AFW system remains operable but non-conforming In regards to ine pumps redrculallon flowpath.'

Last ModifIed Date C*anged From 11/21/2002 2:2a:33 PM To 11/21/2002 3.06.39 PML Lasl Mod~fier Changed From CUNT DRESCHER To RON HARPER I,

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38C I of Po~nz Beac.i .jo¢r PN.'..i OPERATIONS NOTEBOOK FILE

SUBJECT:

AF.v SW MOV power' 5-,*rpi The attached CAP030227 brings up a scenario allowed by our technical specifications where the availability of required AFW flow is questioned The scenario is that one "B" train EDG is aligned to both -B" train buses A seismic event occur_ which results in a loss of off site power, the CST's are lost, and then a single failure results in the loss of the opcralce "B" train EDG This would result in losing power to the AFW pumps SW suction MOV's for P-38B and both TDAFP's. The question now is: "Are 3 of the 4 AFW pumps inoperable due to a single failure?

As described in the attached CAP, P-38A MDAFP and it's SW suction MOV remain fully operable for clie f unit. For the other unit, there is ample time to locally open the SW suction MOV for that unit's P-29 TDAFW pump islich will provide more than the required AFW flow prior to SG drvout. and the SG's can be recovered to normal y."els.

For the postulated scenario, the AFW system remains capable of meeting it's required safety function.

Approved By: Ron Harper Place in Section: OA Info Placed in Notebook: 11122102 Remove By:

Date te Schedule for Removal: DSS Acknowleolgement Night Orders: 4 days or less Crew A:

Operational Information: 31 days or less Crew B:

Significant Events: 31 days or less Crew C:

Industrial Safety: 31 days or less Crew D.

Administrative: 31 days or less Crew E:. _ __ _ _

Operational Experience: 31 days or less Crew F:

Modifications: 31 days or less Miscellaneous: 31 days or less quest for Data. Until data is gathered - 7.

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11122/2002 6 25 53 P'M 11222002 7 5S 30 PM Owner (Nono) Owner PONP CAP Admin t/y CLINT DPESCHER N Vll by RON HARPER IN SECTION 1 Activity Request Id: CAP030227 Activity Type: CAP Submit Date: 11/22J2002 6 2&.*53 PM O One Line Description" Service Water (SW) to Auxiliary Feedwater (AFW) Pump Suction Power Supply issu%.

• Detailed

Description:

11/22/2002 6:25:53 PM - CLINT DRESCHER During further research into electricaJ power supply Issues associated with the AFW qystem. an anomaly was noticed in the power supplies to the motor operated valves (MOVe) botweon the SW system and each pump suction For the most part. the power supplies to the components assodated with turbine driven AFW pump 1 P-29 and motor driven AFW pump P-38A are fed from Unit 1 A-train supplies, and the power supplies to the components assoclated 4h motor driven AFW pump P-38B and turbine dnven AFW pump 2P-29 are fed from Unit 2 BEraln. The anomoly is that the SW .upply MOV to I P-29 (1AF-4006) io powered from Unit 1 B-4aln.

This may pose an issue with aligning the SW system to the AFW pumps following a 1 " of the Condensate Storage Tank (CST) supply due to depletion or loss from a seismic evem. Thi*

may become an issue during the following credible design basis event: a loss of otfoe power (LOOP) from a seismic event combined with a single active failure of a piece of equment Important to safety. The worst case single failure could occur if one of the B-train enprgency diesel generators (EDGs G-03 or G-04) is aligned to the Unit I and Unit 2 B-train bidriS. This condition is allowed by Technical Specifications without entry into a TSAC. This o'!(ration combined with the event mentioned above, would disable the remote opening cap aty of three of the valves (1AF-4006. AF-4016 and 2AF-4006). AF-4016 is associated wt-38B and 2AF-4006 is associated with 2P-29. This would not challenge the operability of aepumps.

except P-38B which is powered from B-train, but would challenge operations to kxCQy align SW to AFW suction in the five minutes as credited In the FSAR.

The Loss Of AC power transient (LOAC) is described in FSAR section 14.1.11. That analysis assumes that only a single motor driven AFW pump is available to a unit, and that flO* is restored within 5 minutes of the loss of feedwater (due to the loss of AC).

m~tor driven The 5 minute /200 gpm criterion would be met for whichever unit is to be fed from AFW pump P-38A. Power would be available to manually open AF-4009 from the cQ.irol room, and promptly (re)start pump P-38A. These actions are procedurally directed.

could be dtched The other unit would net have any feed water available until an Operator open valve to the AFW pump room, rnanually do-clutch the MOV operator, and manually o as s

ieratl locally. These valves awe periodically stroked to ensure free motion, and the to be completed within 5-15 minutes of the lose of power. Loss of power lbltbon expected pror*pndcatk*n MOVs cause the control board position indication ights to de-energize. giving that local manual action is required to reposition the valve.

heat fra<n of Westinghouse WCAP 15154 Table 2-22 conservatively provides the decay is the decay heat free rated thermal power as a function of time post-trip. At 1 minute, .0 dog F 0.039 of the full 102% rated power of 1518.5 MWL or 3.46E+6 BTU/min. Assuming of -381 gpm is required to remo "AFW and an 1100 pela steam generator. a boll-off Therefore, the heat. This is less than the 400 gpim capacity of the turbine driven pump. steam ge metor dry AFW pump is aligned to SW and started at any time prior to turbine driven oided.

out, steam generator level recovery will be achieved and a pressurizer solid condtltof1 From SAMG SAG-1. it Is noted that the time to steam generator dry-out from a no =s t1ieble Is time and margin conservatively 30 minutis for an LOAC event Therefore, ample AFW MOV eniestore to take procedurally directed manual action to open the SW supply to the associated 400 gpm turbine driven pump. Ji Design Initiator: DRESCHER. CLINT A Initiator Department: EDEP Engineera.

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IKge 2 of 3 Elecrical P6 Date/Time of Discovery: 1,2Z_2002 5 36 06 PM DaiefTIme of Occurrence: 111/22/2002 5.35 06 FM Identified By. S.*e-ien:fied System AF PB Equipment # (1 3t): (N ,no) Equipmont Type (It): (None)

Equipment # (2nd): (hone) Equipment Type (2nd): (None)

Equipment # (3rd): (None) Equipment Type (3rd): (None)

Site/Unit: Point Beach - Common Why did this occur?: 11/22/2002 6.25 53 VMi - CLINJT DRESCHER Unkrnown This appears to be pan of the original plant design (as-bull configura:ioN Immediate Action Taken: 11/22/2002 6"25 53 PM - CLINT DRESCHER:

Researched potential consequences of power supply failure In'ialed CAP io track final resolution.

Recommendations: 11/22/2002 6.25.53 PM - CLINT DRESCHER.

Evaluate leasabiluty of powering 1 AF-4006 from Unit 1 A train power to be consjstqdt with similar diverity/redundancy powering schemes found within the plant.

• Notify Me During Evai?: N 0 SRO Review Required?: N SECTION 2 Operable 0 Compensatory Actions: N Operability Status:

Basis for Operability: 11/22/2002 7:55 30 PM - RON HARPER.

Ail AFW pumps and their SW suction MOVW8 are operable.

In the scenario described above, P-38A MDAFW pump and it's associated SW suctibn MOV 6 will remain operable to provide the AFW requirements to one unit For the other uniti the CAP describes that we have ample time to align a P-29 TDAFW pump to the other unit. .le P-29 TDAFW pump SW suction MOV can be locally opened prior to SG dry out to proviq more than the required AFW flow for that unit. For these reasons, the AFW system will be abWi,,o provide the required AFW flow to each unit within the required times and therefore meets required safety function. ,

0 Unplanned TSAC Entry: N S External Notlfcation: N SECTION 3 Screened?: N 1 Significance Level: (None)

INPO OE Reqd7: N Potential MRFF?: N 0 QA/Nuclear Oversight?: N 0 Licensing Review?: N Good CatchWWell Doc'd?: NA SECTION 4 Inappropriate Action: II, Process: (None) Activity: (None)

I; Human Error Type: (None) Human Pert Fall Mode: (None)

Equip Failure Mode: (None) Process Fall Mode: (None)

Org/Mgt Failure Mode: (None) 0 Group Causing Prob: (None) it (qu Hot Buttons:

(None) https'//nmc.tirackonline.com/tTntrack/tmtrack.dll?IssucPagc&Tableld= I000&Recordld=21... If 2/2002 9t 60 3'Wd FCAGSINIOd

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SUBJECT:

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To ensure we are able to maintain the Operability ufow AFV.: pumps il is cssenrial that we are able to accurately detenmine the individual AFW pumps flo,,rates r. o:dCr to maintain the required minlmum flov's for each pump The attached figure shows the arrangement of indi',;dual pump flow indicators and the iotal flow indicators to each S/G. Should a single AFW pump flow indicator fail, i: is still possible to readily determiinc that pumps flow by looking at the total AFW flow to the applicable S;G and subtracting the known flow of any other AFW pump that may be providing flow It may also be possible to readily detcminc individual AFW pump flows for multiple A.FW pump failures and/or individual AkFW pump flow indicators, depending on thý combinzation of failures, utilizing the same methodology If at anytime an indi%idual AFW pump flow cannot be determined to be greater than the minimmza required (50 gpm for P-38AIB and 75 gpm for 1(2)P-29) then the affected AFW pump shall be immediately scured to prevent pump damage until adequate flow can be established Approved By: Place in Section:

Placed in Notebook: 11/22/02 Remove By: 12g2/02 Daic Date Schedule for Removal: DSS Acknowledgement Night Orders: 4 days or less Crew A: "

Operational Information: 31 days or less Crew B:

Significant Events: 31 days or less Crew C:

Industrial Safety: 3 1 days or less re D:

Administrative: 31 days or less Crew E:

Operational Experience- 31 days or less Crcv, F-Modifications. 31 days or less "iscellaneous: 3 1 days or less request for Data: Until data is gathered I.

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FLOW INDICATORS FOR BOTH UNITS 1(2 A 1(2) B

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Pave I or Point Bcach u:UlCZI P.j.t OPERATIONS NOTEBOOK FILE:

SUBJECT:

Contingency Strategy The PSA Group has provided us with a Contingency Strategy for the Failure of one "B" Train FDG in regards to the issue raised by CAP030227. Service Water (SW) to Auxiliary Feedwater tAFW) Pump Suction Power Supply. The Contingency Strategy is attached In summary, there are three key elements of the strategy should we have a faiiure of a "B" train EDG"

1. Align the operable "B" train EDG to both "B" train buses per OI-35A which is our normal pMacticc.

2. Protect the operable "B" train EDG lAW NP 10.3.7 (post the protected signs and list as protected equipment on the Plan Of The Day)

3. Expedite repair and return to service of the failed "1B" train EDG. This means a Priority 2 WO, call in the required support groups, and work around-the-clock.

See the detailed risk discussion in the attached PSA Group writeup.

IC Approved By:  :-ý Ro-nfHarper Place in Sectibn: 0 M. Info Placed in Notebook: 11/23/02 Remove By: 123/02 Date Date Schedule for Removal: DSS Ackno*w ement Night Orders: 4 days or less Crew A:

Operational Information: 31 days or less Crew B:

Significant Events: 31 days or less Industrial Safety: 31 days or less Crew C:

CrewwJ:

1 Administrative: 31 days or less Crew E:

Operational Experience: 31 days or less Crew F:

Modifications: 31 days or less Miscellaneous: 31 days or less iuest for Data: Until data is gathered d

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Contingency Stratcg% for the Failure or One H ['rain EDG Recommended Conrinnencv Actzon{,(1 NI o.aze R.'sk Impact

- Alir, the opcrable B Train EDht,,ooth B Trrain 4K% .,C',rds bjaeb per 01-355A

• Designate the remaining operable B Train EDG a, protected equipment per

,NTP- 10.3 7 Expedite repair and return to service of the failed EDG Discussion If either G03 or G04 becomes inoperable, the normal action would be for Operations to align the remaining operable B Train EDG to both of the B Train 4KV emergency buses.

l-A-06 and 2-A-06, per OI-35A. This is still the correct action to take.

Given the current plant design with service water supply valves for three AFW Pumps (P38B. IP29. and 2P29) fed from B Train, this alignment will make the operability of these service water supply valves vulnerable to the single failure of the remaining operable B Train EDG. However, making this alignment is still the best action to take in response to a B Train EDG failure because:

The random failure probability of the second EDG is relatively low - approximately 5 chances out of.100 (5E-02 probability) over a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> mission time. The alternative action of not aligning the operable EDG to both of the B Train 4KV buses will, in the event of a LOOP, guarantee failure of at least one AFW service water valve (for IP29) if IA06 is left unaligned or two AFW service water valves (for P38B and 2P29) if 2A06 is left unaligned.

" Even with a failure of the second B Train EDG. three AFW pumps will still be available as long as the CST inventory lasts. After that, P38A can be aligned to service water from the Control Room

" For every accident except a seismic event or an ATWS, the CSTs will provide an initial supply of water to the AFW pumps that will last several hours. This will allow plenty of time for a local operator to open the service water supply valves manually if AC power is lost. The failure probability for this manual action is also low - less than 8 chances out of 1000 (8E-03 probability).

A seismic event or an ATWS could require a quick transition to service water as the supply for AFW. This can still be accomplished from the Control Room unless there is also a loss of offsite power. A seismic event with a consequential loss of offsite power occurs with a frequency on the order of 2E-05/year. and an ATWS followed by a random loss of offsite power has a frequency on the order of 3E-09/year.

Prepared By:ý- 1/Jq02.. Approved By:%A IAIyA~ (~~ II)'~ 2 Paul Knoespel Rick Wood EO 3-:Vd I-)'EIIdPLEVSGLOZE ZV*:E,0 zrdrd/s,7/ll