ML20137Y782

Summary of 860108 Meeting W/B&W Owners Group Regulatory Response Group in Bethesda,Md Re Generic Implications of 851226 Loss of Integrated Control Sys Power Event.List of Attendees & Viewgraphs Encl

ML20137Y782
Person / Time
Site:	Rancho Seco
Issue date:	02/25/1986
From:	Paulson W Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 8603120382
Download: ML20137Y782 (30)

Text

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Dmlh o t &

FGbruary 25 1986 t ,.- .

LICENSEE: -Babcock & Wilcox Owners Group (B&WOG)

SUMMARY

OF JANUARY 8, 1986 MEETING WITH THE B&WOG REGULATORY l

RESPONSE GROUP T0. REVIEW THE DECEMBER. 26,~1985 RANC30 SEC0

. TRANSIENT-0.n January 8,1986, the staff met with the B&WOG Regulatory Response Group in Bethesda, Maryland. The' purpose of the meeting was to discuss the generic implications of the December 26, 1985 Rancho Seco loss of integrated control

. system (ICS) power event. Enclosure 1 is a list of attendees. A copy of the.

handouts provided by the B&WOG Regulatory Response Group is also enclosed (Enclosure 2).

The Regulatory Response Group (RRG) sumarized the chronology of events relating to the Rancho Seco transient and discussed the results of the plant-specific assessments of the other operating B&W plants following a postulated loss of ICS power that initiated the Rancho Seco event. The areas evaluated by the B&WOG were: '

-o ICS Power Supplies o Equipment Controlled by' the ICS o Control Room Indicators

.o Backup Means of Control o Procedures and . Training for Loss of ICS Power The RRG presented information to demonstrate that the other B&W plants are sufficiently different such that the transient that occurred at Rancho Seco would not be as severe at the other plants. The RRG also concluded that' due to similarities, additional review of the Rancho Seco event should be undertaken'to identify actions to reduce the frequency and magnitude of transients. .In addition, operator awareness training will be conducted regarding the Rancho Seco event. The B&W Owners Group Executive Committee meeting scheduled for January 16, 1986 will finalize the actions to be taken.

The B&WOG plans in this r.egard will be reported to the staff at a meeting scheduled for February 5,1986. Based on the infonnation presented at the meeting, the ' staff concluded that no immediate action is required for the other B&W plants.

M N 5 M 21 E Walter A. Paulson, Project Manager PWR Project Directorate #6

. Division of PWR Licensing-B

Enclosures:

As Stated cc w/ enclosures:

See nex page-i<1 PBD W WPaulson;cf tk p 86031203G2 960225 PDR ADOCM 05000312 S PDR

l' tf 't' k HEETING

SUMMARY

DISTRIBUTION

• Copies also sent to those people on service (cc) list for subject plant (s).

hketFile; '

NRC PDR L PDR PBD-6 Rdg J JStolz '

WPaulson OELD EJordan BGrimes ACRS-10 NRC Participants ,

RJones LMarsh NLauben n'

GSchwenk GMazetis-BSheron FSchroeder FMiraglia h\ 'DCrutchfield sDEisenhut ,

JStolz RKendall MVirgilio

,RWright

~'

• DThatcher

~c r! SNewberry ASzukiewics HNicolaras

, GDick CMcCracken s s CThomas s' JHeltemes SMiner D.g:'JCrews;R:V WRegan

, i HSilver GKalman

.RWeller JWenniel GVissing JCalvo c RVollmer ADe Agazio JThoma

. RHernan JKopeck .

WPaulson Y _

r Enclosure 1-LIST OF ATTENDEES OF B&WOG MEETING HELD ON JANUARY 10, 1986 Name Affiliation WPaulson NRC/NRR RJones NRC/NRR.

LMarsh NRC/NRR NLauben NRC/NRR GSchwenk NRC/NRR GMazetis NRC/NRR BSheron NRC/NRR FSchroeder NRC/NRR FMiraglia NRC/NRR-PWR-B DEisenhut .NRC/NRR DCrutchfield NRC/NRR JStolz NRC/NRR RKendall NRC/NRR MVirgilio NRC/NRR RWright NRC/NRR DThatcher NRC/NRR-SNewberry NRC/NRR ASzukiewicz NRC/NRR HNicolaras NAC/NRR GDick NRC/NRR CMcCracken NRC/NRR CThomas NRC/NRR JHeltemes NRC/NRR SMiner NRC/NRR JCrevs; NRC/ Region V WRegan NRC/NRR HSilver NRC/NRR GKalman NRC/NRR RWeller NRC/NRR JWermiel NRC/NRR GVissing NRC/NRR JCalvo NRC/NRR RVollmer NRC/NRR ADe Agazio NRC/NRR JThoma NRC/NRR RHernan NRC/NRR JKopeck NRC/NRR RWoodruff NRC/IE RRodriguez SMUD HTucker Duke Power Co.

TEnos AP&L CDoyel Florida Power Corp.

l l

[

4 Name Affiliation RDorman B&W RGanthner B&W RHuston Atomic Industrial Forum EKane B&W JBroughton GPU Nuclear RWilson GPU Nuclear JNurmi Qatel JTaylor -

B&W JMcWilliams AP&L R0akley ' AP&L NRutherford Duke Power Company ESimpson Florida Power Corp.

GWestafer Florida Power Corp.

RWittman Florida Power Corp.

WBandhauer Florida Power Corp.

SRedeker SMUD JLeon KCRA-Ch. 3 Sacto.

GSwindlehurst' Duke Power Company AHosier Wash. Public Power Supply System JBohart B&W CPryor B&W WWilson B&W MWagner Inside NRC LConnor Doc-Search Associates /NRC Calendar CBrinkman C-E CPindzia Serch Licensing MDurivan - TED LStalter TED TMyers TED G. '

PHildebrandt MPR Associates, Inc.

i

. . ' ;, . Enclosure 2 l

NRC / B&WOG REGULATORY RESPONSE GROUP MEETING TO REVIEW 1

THE DECEMBER 26,1985 RANCHO SECO TRANSIENT 1

1 t JANUARY 8,1986 BETHESDA, MARYLAND 1

B&WOG RRG REPRESENTATIVES:

Arkansas Power & Light t Duke Power Company i

Florida Power Corporation GPU Nuclear SMUD Toledo Edison

1 l

B&WOG RRG MEMBERSHIP AND CHRONOLOGY OF RECENT ACTIVITIES 0 RRG MEMBERSHIP - ALL B&W OPERATING PLANTS ARE MEMBERS t

0 RECENT RRG ACTIVITY CHRONOLOGY INDIVIDUAL UTILITY ACTION BEGAN AS SOON AS RANCHO SECO TRANSIENT INFORMATION AVAILABLE.

FIRST RRG TELEPHONE CONFERENCE CALL - 12/31/85:

i DECISION TO ACTIVATE RRG.

- FURTHER INDIVIDUAL UTILITY ASSESSMENT RE ,dLTING FROM RRG TELEPHONE CONFERENCE CALL.

SECOND RRG TELEPHONE CONFERENCE CALL -

1/2/86:

AGREEMENT ON SCOPE OF RRG ACTIVITIES.

THIRD RRG TELEPHONE CONFERENCE CALL -

1/6/86.

RRG MEETING -

1/7/86.

RRG/NRC MEETING - 1/8/86.

i

NRC/B&WOG RRG MEETING JANUARY 8,1986 AGENDA

1. Introduction H.B. Tucker /DPC (10 min) i ll. Rancho Seco Transient R.J. Rodriquez/SMUD (15 min) 111. Plant-Specific Assessment Results

- Hardware &

- Function Comparisons C.B. Doyel/FPC (45 min)

- Procedures, Training and J.T. Enos/AP&L (15 min)

. Plant Performance l IV. Preliminary Conclusions H.B. Tucker /DPC ( 5 min)

& B&WOG Actions i

!' s.

)

,y w w w-y,5 ---,w-g-.

evT-- -ye-- y+, , .%-o.-.www -,e,----y,~, gw .y -3y..,mm ,py, _ y .,-%w --.

TO OTHER OTSG h

DUAL DRIVE AFW PUMP TURBINE BYPASS VALVES l' h FROM CONDENSATE STORAGE MOTOR DRIVEN NORMAL AFW TANK AFW PUMP CONTROL VLV g k I

>d MAIN THROTTLE MFW g VALVE SFAS REGULATING MAIN U OPER y VALVE I BLOCK VLV CONTL TMOSPHERIC TEAM VLV DUMP VALVES

=

FROM MAIN FEED MAIN STEAM SYSTEM PUMP STARTUP (MSS)

CONTROL FEEDWATER SYSTEM (FWS)

Rancho Seco

4- - ' - -

SEQUENCE OF EVENTS

SUMMARY

RANCHO SECO TRANSIENT 12/26/85 I

INITIAL CONDITIONS: DECEMBER 26,1985 ,

76% REACTOR POWER ICS IN FULL AUTOMATIC CONTROL f

IlME EVENT 04:13:47 LOSS OF ICS DC POWER VALVES MOVE TO 50% OPEN POSITION TURBINE BYPASS VALVES (TBV)

ATMOSPHERIC DUMP VALVES (ADV)

MAIN FEED WATER REGULATING VALVES (MFW)

AUXILIARY FEEDWATER VALVES (AFW)

MAIN FEED PUMPS GO TO MINIMUM SPEED 04:14:01 MOTOR DRIVEN AUXILIARY FEEDWATER PUMP (AFW)

STARTS AT 850 psig MAIN FEEDWATER PUMP i DISCHARGE PRESSURE l

04:14:03 REACTOR TRIPS ON HIGH RCS PRESSURE 04:14:06 TURBINE DRIVEN AUXILIARY FEED PUMP (AFW)

STARTS

04

14:11 AFW FLOW TO BOTH OTSGs 04:14:25 OPERATORS INCREASE RCS MAKEUP AS PART OF PROCEDURE E,02 " VITAL SYSTEM VERIFICATION" i 04:14:30 OPERATORS SENT TO ISOLATE TBVs, ADVs, AND i AFW VALVES, OPERATORS RECOGNIZE EXCESSIVE

! COOLDOWN RATE.

04:15:04 OPERATORS MANUALLY START "B" HIGH PRESSURE INJECTION PUMP (HPI) TO FURTHER INCREASE

, RCS MAKEUP.

i i

vv-e--ge - -

SEQUENCE OF EVENTS

SUMMARY

(CONT'D.)

IlME EVENT 04:16:02 OPERATORS MANUALLY TRIP BOTH MAIN FEEDWATER PUMPS, ACTUAL MAIN FEED FLOW WAS ZERO SINCE 04:14:03.

AFW FLOW APPROXIMATELY 1100 GPM TO EACH STEAM l GENERATOR.

l

\

04:16:57 SAFETY FEATURES (SFAS) AUTO INITIATION AT RCS PRESSURE OF 1600 psig 04:17:10 OPERATOR SHUTS SFAS ACTUATED AFW VALVES.

1 04:20:00 PRESSURIZER LEVEL OFFSCALE LOW 04:23:00 TBV AND ADV ISOLATED LOCALLY.

04:23:10 AFW VALVE TO "B" STEAM GENERATOR PARTIALLY CLOSED.

FLOW DECREASED TO "B" STEAM GENERATOR BY 60%.

04:26:22 AFW VALVE TO "A" STEAM GENERATOR CLOSED, OPERATOR BELIEVES VALVE ONLY 80% SHUT.

i 04:26:47 PRESSURlZER LEVEL BACK ON SCALE

! 04:29:40 OPERATOR ATTEMPTS TO CLOSE AFW VALVE TO "A" OTSG  !

FURTHER. VALVE FAILS OPEN.

04:30:30 OPERATORS BEGIN DEPRESSURIZlNG RCS TO MOVE OUT OF PTS REGION.

04:33 AFW VALVE TO "B" STEAM GENERATOR IS FULLY CLOSED.

ALL FEEDWATER FLOW TO "B" STEAM GENERATOR IS STOPPED.

, 04:40:00 ICS DC POWER RESTORED. OPERATORS SHUT AFW VALVES, l

TBV, AND ADVs FROM CONTROL ROOM. COOLDOWN CEASES l AT 386*F. l l

Simplified Functional Relationship.of I&C Systems -

Safety Non-Safety RPS NUCLEAR HEASUREMENIS M HEUTRON B0P CWDCS ISOLAil0N DEVICE FLUX h E l NCIATION g

NON-NUCLEAR

• ISOLATION ICS HE ASUREMENT S __

f _

DEVICE RC FLOW - CONTROL OF SELECT l

' dl TO CRD TRIP 4

& PUMPS. BYPASS ISOLAIl0N -

BREAKERS - ~

VALVES. TURBINE E DEVICE CRDCS)

. ESFAS l

BUIL0 LNG y l 1r ICS INPUTS PRESSURE FROM NNI RC PRESSURE g

l j tL TO HPl 2

' U '

& LPI TO BUILDING g

• ---> ANNUNC I ATI ON. INDICATION

- ISOL ATION &

RECORDING SPRAY NNI SG EVR

? -.-p CONTROL OF SELECTED 1 r SS l ELEMENTS (PRESSURIZER I W CONTROL OF yy SPRAY & NEATERS, PRlHARY PUMP STATUS EFW ELEMENTS EfW HAKEUP.PORV)

AUTO + -> (V ALVES, PUNPS)

CONTROL START l

l

AREAS BEING EVALUATED BY RRG l

RELATIVE TO i i

RANCHO SECO TRANSIENT O ICS POWER SUPPLIES O EQUIPMENT CONTROLLED BY ICS 0 CONTROL ROOM INDIC ATORS  :

1 l

0 BACKUP MEANS OF CONTROL ,

d.. PROCEDURES AND TRAINING FOR LOSS OF ICS POWER r

B&WOG RRG ASSESSMENT OF R/S 12/26/85 TRANSIENT 0 ICS POWER SUPPLIES -

COMPARED POWER SUPPLY DESIGNS 1 --

EVALUATED RANCHO SECO INITIATING EVENT 1

0 EQUIPMENT CONTROLLED BY ICS 1

DETERMINED COMPONENTS CONTROLLED /

AFFECTED BY ICS DETERMINED FAILURE MODES (LOSS OF ICS POWER)

COMPARED FAILURE MODES AT B&W PLANTS l --

IDENTIFIED DIFFERENCES AND POTENTIAL IMPROVEMENT

^

B&WOG RRG ASSE$SMENT OF R/S 12/26/85 TRANSIENT ,

l l

0 BACKUP MEANS OF CONTROL

~

-- AVAILABILITY OF MANUAL CONTROL OF ICS COMPONENTS IN CONTROL ROOM

-- AVAILABILITY OF OTHER BY-PASS CONTROL CIRCUlTS l

-- AVAILABILITY OF NON-ICS COMPONENTS THAT CAN 4

ACCOMPLISH MISSION 9

l 0 CONTROL ROOM INDICATORS

-- EVALUATED AVAILABILITY OF DIRECT CONTROL ROOM '

INDICATION FOR LOSS OF ICS POWER i

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I 1

1

820 System: CR-3, Davis Besso, Rancho Seco and ANO-1 IE or IE or I .8 ATTERY 8 ACKE0

-l OH lE

2. VITAL OlSTR*

I. INVERTER WI TH STATIC SWITCH ~~ 'F

2. BATTERY BACKED

. NVE ER REG.

INVERTER

3. REG INST. BUS

4. AUXil PWR. OlSTR. STATIC BUS STATIC

• SWITCH *" $wlygg C

E 00 I n 1P 120 VAC 120 V AC BACKUP PREFERRED ,

POWER POWER SYSTEM CA8INET AC FIELO LOADS e

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+

+24 VOC l VOC

-- , u POWER i MONITOR TO:

RECO RDERS

-24 d I N DI C ATORS V OC g( ,

yh  % H/A STATIONS AUX RELAYS f__ s

/ T

-24 VOC +24 VOC BUS BUS

.721 System TMl-1 ES EDS

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Bus.

REG.

2 Bus.

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il!.sTRUMEN TATIO ICSF COMTROLs i PNI L _. 7_.

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721 System Oconoo 125 VDC BUS 125 VDC BUS ISOLATING & TRANSFER l18 VAC REGULATED BUS DIODES HANUAL SW INVERTER TRANSFER e b SWITCH N.C.

ELECTRO /HECHANIC AL TRANSFER SWITCH

. H.C. HANUAL SW

'N.O.'

I I I (I (I (l i (I (,I I ENERG ENERG FAN AUTO HAND l l l

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8 l \

l \ SELECTED I CONTROLS

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1r1 RIP h if IP 1P if 5*

i = g I SW SEL ECTED r-- - L-7 30 P CONTROLS tl NSTRUMEN ~TAT 103 ICSF CONTROLS l NNI L - T- - J SELECTED INDICATIONS

EQUIPMENT CONTROLLED BY ICS

, (ORIGINAL DESIGN)

TURBINE BYPASS VALVE -(TBV)

ATMOSPHERIC DUMP VALVE (ADV)

EMERGENCY FEEDWATER CONTROL VALVE I

STARTUP FEEDWATER VALVE (SUV)

MAIN FEEDWATER VALVE (MFW)

MAIN FEEDWATER PUMP TURBINE GOVERNOR CONTROL RODS MAIN TURBINE GOVERNOR 1 I

f l

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S D . L SC E A EI E U V Y P N LF 1 E S A S -

AL - L M I V O I0 % A A  % N S S N A2 0 / / 0  % I O S E YS A B8 5 N N 5 0 M T A Y E4 KI FG FN I

SN M .

L NA OI L P A IL AR Y R U TO TE E N -

IF SV L 0 A S 0 M I S YI I0 A A  % 2 S O RR A2  % / / 0  % 4 O S E P C B8 0 N N 5 0 T A Y L

M A P U Y R N SE E A S IS L 0 M I VS I0 . A  % 9 S AE A2  %  % / 0  % 6 O S E DD B8 0 0 N 5 0 4 T A Y O Y L HO E M A S CC L  % P U I NE I0  %  %  % 0 R N AS A2 0 0 0 5  % A S O R B8 5 5 5 0 0 M A N 0 .

6 O 2 T E

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T O

R W

FH H O I Ts N

R B NV T T T R T RR AI E N PA WA PO N UO LS

• M OS UP FP MN O TN PM P CE T UR C R IE V V RW NW PE NE SE UP P V WL AD I4 V D IV EV QY B D FA TI AI FO O AO OA ET T A EV SF MF MG R MG DH m

POSIT ON FF MEY VALVES AN7 SYSTEMS

, FC ING 14SS OF ICS AC POWER -

RANCHO DAVIS CRYSTAL SECO BESSE RIVER ANO-1 OCONEE TMI-1 -

EQUIPMENT BAILEY BAILEY BAILEY 1

TYPE 820 820 BAILEY BAILEY . BAILEY 820 820 721 721 TBPV 50% 0% 0% 50% 0% 0%

ADV 50% 0% N/A N/A N/A N/A E ROL 50% N/A N/A N/A N/A

• 50%

STARTUP FW 50% 50% 50%

FIDW PATH 50% 504 50%

MAIN FW 0% 0% 0%

FIDW PATH 0% 50% 0%

MF PUMP AS-IS AS-IS GOVERNOR AS-IS AS-IS AUTO TRIP 4100 RPM ON IDSS OF l  :

ICS POWER ROD CONTROL AS-IS AS-IS AS-IS AS-IS AUTO TRIP ON AS-IS TRIP OF MF PUMPS MAIN TURBINE AS-IS' AS-IS AS-IS l

AS-IS AUTO TRIP ON AS-IS TRIP OF MF PUMPS DOES PLANT NO YES YES HAVE MSIVs? YES . NO YES o

CAVITATING VENTURI

POSITIFNS CF KEY VALVES AND SYSTEMS

• FOLLOWING LOSS LF ICS DC POWER RANCHO DAVIS CRYSTAL .

SECO BESSE RIVER ANO-1 OCONEE TMI-1 EQUIPMENT BAILEY BAILEY TYPE 820 820 BAILEY BAILEY 820 820 BAILEY BAILEY TBPV 721 721 50% 0% 0% 50%

• N/A N/A ADV 50% on N/A N/A -

N/A N/A EFW CONTROL 50% N/A VALVES N/A N/A N/A N/A STARTUP FW 50% *** 50% **

FLOW PATH 5 0 % '" 50% N/A N/A MAIN FW 0% 0%

FLOi PATH 0% 0%

N/A N/A MF PUMP 2600 RPM GOVERNOR 4690 RPM 4200 RPM MIN SPEED N/A N/A ROD CONTROL TO MANUAL TO MANUAL TO MANUAL TO MANUAL N/A N/A g ] BINE As Is As Is AS IS AS 15 N/A .N/A DOES PLANT NO YES HAVE MSIVs? , YES YES NO YES 5 .

MSIV CIOSURE ee SPRCS MAIN FEED FUMP 'IRIP

CONTROL ROOM INDICATIONS FOR LOSS OF ICS POWER RANCHO DAVIS INDICATION SECQ BESSE CR-3 ANO-1 OCONEE TMl-1

, ANNUNCIATOR ~X X X X X X LOSS OF LIGHTS X X X X X X ON HAND / AUTO STATIONS PLANT X X -- --

X --

COMPUTER POWER STATUS LIGHT -- --

X X --

X BLOWN FUSE --

X X --

X --

INDICATOR EVENTS -- --

X -- -- --

RECORDER ICSINVERTER X X --

X X X I

\

i )

l

I S' CS Dh b ~

i RANCHO DAVIS CRYSTAL

• i SECO BESSE RIVER ANO-1 OCONEE TMI-1 IPMENT BAILEY BAILEY BAILEY BAILEY PE 820 820 820 BAILEY BAILEY 820 721 721 TBPV 50% 0% 0% 50% N/A N/A ADV 50% 0% N/A N/A N/A' N/A EFW CONTROL 50% N/A N/A VALVES N/A N/A N/A

, STARTUP FW 50% 50% 50%

FIDW PATH 50% N/A l

N/A MAIN FW 0% 0% 0% '

FIDW PATH 0% N/A N/A l MF PUMP 2600 RPM 4690 RPM 4200 RPM MIN SPEED GOVERNOR N/A N/A ROD CONTROL TO MANUAL TO MANUAL TO MANUAL TO MANUAL N/A N/A g BINE AS IS As IS AS IS AS IS N/A N/A DOES PLANT NO YES YES HAVE MSIVs? YES NO YES

^

r-- - e 7 --r- -m - m -

m - --

-t 7 ' - - -+ r w - _

.. .- . ANTICIPATED RESPONSE TO LOSS OF ICS POWER ANO-1 T=0 LOSS OF ICS DC POWFP

-- TBV GOES TO 50%

-- STARTUP FEEDWATER VALVE GOES TO 50%

l

-- MFW PUMP RUNBACK TO MINIMUM SPEED MFW BLOCK AND LO-LOAD BLOCKS GO TO 0%

-- ADV REMAIN AT 0%

O PLANT RESPONSE i

-- MFW FLOW DECREASING RCS PRESSURE INCREASING

-- SG LEVEL DECREASING T=8 sec. RX TRIP ON HIGH PRESSURE

-- TURBINE TRIP

-- ONE MFW PUMP TRIPS i  !

(OPERATOR CLOSES MSIVs PER PROCEDURE)*

0 PLANT RESPONSE f

RCS TEMPERATURE DECREASING RCS PRESSURE DECREASING STM GENERATOR PRESSURE INITIALLY INCREASING j

STM GENERATOR LEVEL DECREASING (WlLL GET EFIC EFW ACTUATION ON .

LO-LEVEL IN ~ 30 SEC.)

• TO FURTHER EVALUATE TRANSIENT, IT IS ASSUMED OPERATOR DOES NOT PERFORM THIS ACTION.

ANO-1 RESPONSE (Cont'd)

T=12 mins: SG PRESSURE DROPS BELOW 600 PSI EFIC MSLI ACTUATION

-- MAIN STEAM LINE ISOLATION VALVES CLOSE

-- MAIN FEEDWATER ISOLATION VALVES CLOSE

-- ADV BLOCK VALVE OPENS

-- ADVs CLOSED (PRESSURE LESS THAN SETPOINT)

O PLANT RESPONSE

-- RCS PRESSURE INCREASING -

-- RCS TEMPERATURE STABILIZES

-- SG PRESSURE INCREASING

-- SG LEVEL MAINTAINED AT EFIC SETPOINT T=20 mins: SG LEVEL RETURNS TO SETPOINT

-- EFW VALVES BEGIN TO MODULATE TO CONTROL LEVEL

-- ADV's BEGIN TO MODULATE TO CONTROL PRESSURE O PLANT RESPONSE

-- RCS TEMPERATURE INCREASING

-- RCS PRESSURE STABillZED

-- SG LEVEL STABLIZED AT SETPOINT

-- SG PRESSURE STABILIZED AT SETPOINT ALL PARAMETERS RETURNING TO HOT SHUTDOWN CONDITIONS.

I PRELIMINARY PROCEDURE ASSESSMENT RESULTS 0 PROCEDURES EXIST IN ALL PLANTS FOR DEALING ,

WITH THE SYMPTOMS AND CONSEQUENCES OF LOSS  :

OF ICS POWER.

O ABNORMAL TRANSIENT OPERATING GUIDELINES (ATOG) TECHNICAL BASIS DOCUMENT IS SOUND; PRELIMINARY ASSESSMENT OF R/S TRANSIENT DOES NOT INDICATE NEED TO REVISE.

O CLARIFICATION OF CRITERIA REGARDING WHEN TO ,

l TAKE CERTAIN SPECIFIC ACTIONS MAY BE APPROPRIATE. G.

t O FURTHER DETAILED REVIEW IS APPROPRIATE AND IS UNDERWAY.

(

PROCEDURE ASSESSMENT i

O CONSIDERATION GIVEN TO:  ;

-- PROCEDURES FOR DEALING WITH TRANSIENTS INITIATED BY THE LOSS OF ICS POWER  !

-- THE EXPECTED RESPONSE OF ICS CONTROLLED EQUIPMENT AND THE RESULTANT EFFECT ON ON THE NSS

-- PROCEDURES FOR DEALING WITH THE RESTORATION OF ICS POWER ROLE OF ABNORMAL TRANSIENT OPERATING -

GUIDELINES (ATOG)  ;

l 0 GENERAL APPROACH:

i

! i REVIEW OF PROCEDURE CONTENT '

i

-- OPERATOR INTERVIEWS I l

t 1

l 1

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

a a EOLLOW-ON B&WOG PROCEDURES AND TRAINING REVIEW IN RESPONSE TO THE 12/26/85 RANCHO SECO TRANSIENI .

p  ?

1. REVIEW OF TRAINING RECORDS TO ASSURE THAT '

OPERATORS HAVE RECElVED TRAINING ON THE LOSS OF ICS POWER SUPPLY EVENT AND IF THE INDIVIDUAL HAS NOT, WILL SCHEDULE THE INDIVIDUAL FOR l

TRAINING.

2. CONFlRMATORY REVIEW OF THE ATOG TECHNICAL BASES DOCUMENT WILL BE PERFORMED.

3. REVIEW OF THE PLANT-SPECIFIC PROCEDURES FOR IMPLEMENTING ATOG.

4. REVIEW PLANT-SPECIFIC PROCEDURES FOR

RESTORATION OF ICS POWER.

5. ISSUE INFORMATION TO FAMILIARIZE OPERATORS WITH THE RANCHO SECO EVENT.

1 I

~

l i ,

i l

l l

CONCLUSIONS OF RRG l 0 DUE TO PLANT DIFFERENCES, A TRANSIENT INITIATED BY LOSS OF POWER TO ICS, SUCH AS THE RANCHO SECO EVENT, AT ANY B&W PLANT OTHER THAN RANCHO SECO I WOULD RESULT IN MUCH LESS SEVERE TEMPERATURE i CHANGES.

0 DUE TO SIMILARITIES, THE RRG HAS CONCLUDED THAT ADDITIONAL REVIEW OF THE RANCHO SECO EVENT SHOULD I BE UNDERTAKEN AS MORE COMPLETE INFORMATION IS l MADE AVAILABLE FROM INVESTIGATIONS BY NRC, SMUD, i OR OTHER SOURCES. THE INTENT OF THIS REVIEW SHOULD BE TO IDENTIFY ACTIONS TO BE TAKEN BY B&WOG MEMBERS TO REDUCE THE FREQUENCY AND MAGNITUDE .

OF TRANSIENTS.

O THEREFORE, AS CHAIRMAN OF THE B&WOG EXECUTIVE COMMITTEE, I HAVE INSTRUCTED THE CHAIRMAN OF THE B&WOG STEERING COMMITTEE TO DEVELOP A PROPOSED PROGRAM OF REVIEW AND PRESENT THAT TO THE B&WOG EXECUTIVE COMMITTEE AT A MEETING JANUARY 16,1986. l

! AT THAT MEETING WE WILL DETERMINE THE SCOPE AND 4

SCHEDULE OF REVIEW WITH THE INTENT OF INCORPORATING THE ACTIONS STEMMING FROM THE RANCHO SECO TRANSIENT INTO THE REVIEWS AND ACTIONS l

CURRENTLY UNDERWAY AS A RESULT OF THE DAVIS BESSE  !

EVENT OF JUNE 9,1985.

l

'l

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

CONCLUSIONS OF RRG (Cont'd) 0 THE GENERAL DIRECTION OF B&WOG PROGRAMS FOR REDUCING TRANSIENTS AND SCRAMS IS SOUND AND WILL

, CONTINUE. EMPHASIS IS BEING GIVEN TO THE SECONDARY PORTION OF THE PLANTS. BOTH THE RECENT DAVIS BESSE AND RANCHO SECO TRANSIENTS RE-EMPHASIZE THE IMPORTANCE OF THIS DIRECTION. THE RELATIVE PRIORITY AND SCHEDULE OF THESE EXISTING PROGRAMS IS BEING.  ;

RE-EVALUATED.  !

i 0 INCREASED NRC FAMILIARITY WITH EXISTING AND >

PLANNED B&WOG ACTIONS RELATIVE TO TRANSIENT REDUCTION IS APPROPRIATE. ALTHOUGH MUCH OF THIS  !

ACTIVITY INVOLVES THE NON-SAFETY RELATED PORTIONS i OF THE PLANT, THE B&WOG INVITES NRC INPUT ON THESE PRO.lECTS. THE ESTABLISHED MODES OF COMMUNICATION REGARDING B&WOG PROGRAMS ARE APPROPRIATE FOR THESE INTERACTIONS. 4 i

4 I I e

1

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