ML18033A177

Proposed Revised Tech Specs,Implementing Recommendations of Generic Ltr 84-15, Proposed Staff Actions to Improve & Maintain Diesel Generator Reliability.

ML18033A177
Person / Time
Site:	Browns Ferry
Issue date:	04/13/1988
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML18033A176	List: ML18033A174 ML18033A177
References
GL-84-15, TAC-00092, TAC-00093, TAC-00094, TAC-92, TAC-93, TAC-94, NUDOCS 8804210027
Download: ML18033A177 (22)

Text

LIYITIHG CONDITIONS FOR 'OPERA IOK SURVEILIAN L RR:,>JICcFP5LIc .S 3.9.B. eratlon w2th Ino erable 4.9.B. O~ierat1on <<'2th In~cd >c chttlc

~au1 ment Rgu2 pmcecct

~ Whenever the reactor 2:s'n Startup mode or Run mode anc2

• not in a cold condition, the availability of electric power shall be as specified in 3.9.A except as specified herein.

1. From and after the date 1. When only one that only one offsite of fsite power. source.

power source is available, is OPERABLE, al 1 reactor operation is permissible for 7 days. generators ~

units 1 and 2 diesel must be demonstrated to.

~ed-4~~ thereafter.

2., From and after the date 2..

when a required that the 4-kV bus tie offsite power source board becomes INOPERABLE, is unavailable to reactor operation is unit 1 because the permissible indefinitely 4-kV bus tie board provided one of the or -a start bus is required offsite power INOPERABLE, all sources is not supplied from the 161;kV system through the bus tie board.

unit 1 generators and 2.

~ diesel shall be demonstrated OPERABLE thereafter. The remaining offsite source and associated buses shall be. checked to be energized daily.

88042i0027 880%is PDR ADOCK 05000259 P DCD BFN 3.9/C.g-e Unit 1

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LIP.'I . INU COt4:>'.. I e)M'.: POi. Oi'EitS. 'Ol' UR'L'Ll 't', RE@'v'IRENE!'~'pera',

for: I:I tt. Ino et at le I.b ~ L. 0 >er a t. lot. Wi t ti Ino er able eius ment EcCu! >e I.

o.'he en'tier.

Wheti one of the units ) ot>e and 2 diesel. aerierator is un1ts 1 arid "'iesel

- INOPERhBLL', cOttt inued generators 'is . f ound reactor- oper'at.ion is .to 'be INOPERABLE ~ .

permissible during the all of tlie ~-RHR.

succeeding 7 aays.

provided that 2 offsite power. sources are avai I table as speci f1ed remaining diesel in 3.9.J .l.c and all of'he

'generators CS..RHR (LPCI and containment cool ing)

~'hal'1 be systems. and the remaining "

demonstrated to be three units 1 and 2 diesel generators are OPERAB'.

If this 'requirement .cannot thereafter.

be met, an orderly shutdown shall be initiated and the reactor shall be shut down and in, the cold condition with1n 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. eel When one units 1 and 2 4. When one 4-kV 4-kV shutdown board is shutdown board is INOPERABLE. continued found to be reactor operation is ei r'iPre INOPERABLE, all permissible for a period of 5 days provided that 2 offsi.te"power sources are .avai:lable as generators~~d specified in 3.9.A.l.c and the remaining boards and 4-kV'hutdown

'he associated remaining 4-kV CS, diesel'enerators, RHP. (LPCI shutdown boards and-containment cooling) shall be systems, and all 480-V demonstrated to be emergency, power boards, are OPERABLE. If this requirement cannot be thereafter.

met, an orderly shutdown e shall be 1nitiated and the reactor shall be shut

.down and in the cold condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

BPN 3.9/4.9-9 Unit 1

11 l

S

'Y~~IHC COND 'Ol" FOi. OPEke". 10t': SURVEILLANE L kE~>ul kHPtEt".":'.9.B.

0ier'at.ion With lnor>erabl << C.S.B. Q>iet at1on.with in~oeralilc meri: 'Eau1 EcCul men1 t"hen on<< of the nutdovm 4'h<<lE 8 shut 4~i bu.'.

buses 's INOPERi.BLE, found to bt.

reactor operation'is 1HOPL'BABLE, a11 permissible for a period 1 and 2 diesel of 7 days'.* generators shall be proven OPERABLE u

6. When one of the 480-V 6. When one -units-1

. diesel auxiliary board" and 2 diesel becomes INOPERABLE, auxiliary board .is reactor operation is permissible for a period of .5 days.

found to be .

INOPERABLE, ~

each unit 1 and 2 diesel generator shall be proven

-. OPERABLE

-da4+y-thereafter.

/

+ ~ ra~~

2.

7. From and after the date I that one of the three 250-V unit batte'ries and/or its associated battery board is found to ~ ~g.

be INOPERABLE reason, for any continued reactor

~t(' g~

operation is permissible during the succeeding 7 days. .Except for

. routine surveillance testing. NRC shall be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the situation,,the precautions to be taken d'uring this period, and the plans'o return the failed component to an OPERABLE- state.

BFN 3.9/4.9-10 Vnit 1

~ I 3.9/4.9 AUXILIARY ELECTRICAL SYSTEM LIMITING CONDITIONS POR OPERATION SURVEILULNCE.REQUIREMENTS 3.9.8. 0 eration with Ino erable 4.9.B. 0 eration with Ino erable E~ui ment ~nut ment Whenever the reactor is in STARTUP mode or RUN mode and.

not in a cold condition, the-availability of electric power shall be as specified in 3.9.A except as specified herein.

1. Prom.and after the date When only one that only one offsite offsite power source power source is available, is OPERABLE, all

'reactor operation is units 1 and 2 diesel permissible for 7 days. generators and-must be demonstrated to wndM~ thereafter.

2. From and after the date 2. When a required that the 4-kV bus tie offsite power source board becomes INOPERABLE, is unavailable to reactor operation is unit 1 because the permissible indefinitely 4-kV bus tie board provided one of the =

or a start bus is required offsite power INOPERABLE, all sources is not supplied unit 1 and 2 diesel from the 161-kV system generators nnd-through the bus tie board. shall be demonstrated OPERABLE thereafter. = The remaining offsite source and associated buses shall be checked to 'be energized daily.

4l MW AW~

3FN ". 3/4. 3- 3

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1'll LIj. Ylhk COj'D 'ON".. POF OPERh. IOt, GtJRVEILLZ N E. REPJIRE>~~.".

. 3.9.8.. erat Ionh Irido ierab) e 4.9.B. 0 e. at 1ont.with Irido er abl c etraui ment ettEu1 ment

3. linen one. of the units 1 3. When one of the and'. di<<sel ge>>er'ator is units I and 2 diesel INOPERAULL, .continued generators i"" found reactor operation's to be INOPERABLE, permissible during the all of the W~jHR--

succeeding 7 days, provided that 2 offsite powe'r sources are available as specified remaining diesel in 3t9.A.l.c and all of generators end-the CS, RHR (LPCI and-containment cooling) s;hall be systems, and the remaining demonstrated to be, three units I'and 2 are OPERABLE.

diesel-'enerat'ors If this requirement cannot thereafter.

r/'~

~

be met, an orderly S

shutdown shall be 1 1nitiate'd and the reactor shall be shut down and in the'old condition within 24 hours. /A~~~~

g 4 ~ When one units 1 and 2 4. '"When one 4-kV 4-kV shutdown board is shutdown board is INOPERABLE, continued found to be reactor operation is INOPERABLE, all

,permissMle for a period of 5 days provided that 2 offsite power sources are available as generators~s , <rnd-specified in 3.9.A.l.c e and the remaining 4-kV ~ I 4t/M~~

shutdown boards and associated diesel the remaining 4-kV generators, CS, RHR (LPCI shutdown boards and conta1nment coo11ng) shall be systems, and all 480-V demonstrated to be emergency power boards are OPERABLE. If this requ1rement cannot be met, an orderly shutdown shall be init1ated= and the reacto. shall, be shut 2.4~~ ~

down and 1n the cold condition within 24 hou.s.

/Q BPN 3.9/4.9-9 Unit 2

AU>:":hP.' Eee' I

."h'S'E"'IMNI, INGe CORDI IONG" POP. OPERA'ION SURVEIL~ 6 REQUIRENEh S 3.9'.B. 0'eration With Ino crab]e 4.9.S. 0 erat ion With Ino~erahle

~Eui'ent ~Eu1 ment.

5. When one of the. shutdown 5. When a shutd~ bus buses ls INOPERABLC, is found to be reactor operat'ion is INOPERABLE. all' permissible for a period" and 2 diesel of l days. .generators. shall be proven OPERABLE 6; -When one of the 480-V When one units l diesel auxiliary boards and 2'diesel becomes INOPERABLE, auxiliary board is reactor operation is found to be permissible for a period INOPERABLEe. Che of 5 days each-unit 1 and 2 diesel generator shall be proven OPERABLE i d ekko thereafter.

7. Prom and that one after the date of the three nM4'4 ~m ~ y~~

250-V unit batteries and/or its asso'elated battery board is found to be INOPERABLE for any reason'. continued reactor operation is permissible during the succeeding 7 days.. Except for routine. surveillance testing, NRC shall be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

of the situation, the precautions to be taken during this period, and the plans to 'return the failed component to an OPERABLE state BPN 3.9/4.9-10 Unit 2

V'I f'

.9/4.9 AUXILIARY ELECTRICAL SYSTEM LIMITISG CONDITIONS FOR OPERATION SURVEIl LANCE. REQUIREMENTS 3.9.B. 0 eration with Ino erable 4.9.B. 0 eration with Ino erable

~Eui. ment ~Eut ment Whenever the reactor is .in, STARTUP mode or RUN mode and not in'a Cold- Condition. the availability of electric power shall be as specified in 3.9.A except as specified herein.

l. 'From and.after the date 1. When only one that only one offsite offsite po~er source power .source is available, reactor operation is permissible under this is OPERABLE, diesel generators ~

all unit must 3

condition for seven days. be demonstrated to be OPERABLE

-4a44y thereafter.

When one unit 3 diesel 2. When one unit 3 generator (3A; 3B, 3C, diesel generator is or 3D) is INOPERABLE, found to be =

continued reactor operation INOPERABLE, all of is permissible during the succeeding 7 days, provided that two offsite power sources are available as the remai.ning unit 3 specified in 3.9.A.l.c. diesel generators. end-and all of the CS, RHR shall (LPCI and containment be demonstrated to be cooling) systems, and the OPERABLE remaining thr'ee unit 3 -aac~4+y thereafter.

diesel generators are OPERABLE If this require-

. ment cannot be met, an orderly shutdown shall be initiated and the reactor shall be. shut down and i.n the Cold Condition within

~ 24 hours.

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mApq Et E~keCAe t yc TE~

e LIMNI INC COND'10ldS POk OPERAT10N SUk VE I LLANOL - k EQU I R EVENTS e

3.9.B. 0 eration With Ino erable 4.9.B. 0 eration W.'th Ino erable e~ul ment ettaui >ment

3. Prom and after 'the date 3. When a required:

"that the. 4-kV bus tie off ite power source board becomes. inoperable," is unavailable

- reactor operation is because the 4-kV permissible indefinitely bus tie board or-a provided one of the start bus is all

~

required offsite power sources is not

'uppl'ied from -the 161-kV system through the bus tie board,.

INOPERABLE, unit 3 ge'nerators shall .be

~

diesel demonstrated

~ad-dekky thereafter.

The remaining of fsite source and associated shall be checked 'uses to be energized daily.

.When one unit 3 4. When one unit 3 4-kV=

4-kV shutdown board is shutdown board is INOPERABLE, continued found to be

.reactor operation is INOPERABLE, all permissible for a period of 5 days provided that offsite 2

are available as specified in 3.9.A.l.c power sources " generators ~~d and the remaining unit 3 4-kV shutdown 'boards and .

associated diesel the, remaining 4-kV .

generators, CS. RHR (LPCI shutdown boards and containment cooling) shall be systems, and all unit demonstrated to be emergency power 3'80-V boards are OPERABLE. If thereafter.

this requirement cannot be met, an orderly shutdown

.shall be initiated and

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the reactor shall be shut V-k v p

down and in the Cold Condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

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BPN-Unit 3 3.9/4.9-9 r.-~ r e. ~~ C~

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~ ~ e' mpp> E E tmft,A) ( yctmEN mrJ'r (gled;",, jQlq". Fujt 'Q: Ekn 'J jlt '.> JkVE I ~:.AN l: HE,>U I REY>EN"."~

3. 9.8. 0 >er at ion Witt> 1no ><<rgb le 4.9.B. O~>eratlon With 1no:>eral>le .

etCEuk ment. E:~ui ment

5. 'rom and after the date Wrren one 480- V diesel

that one of the 480.-V, auxiliary board diesel-auxiliary board is fourrd INOPKRABLL.

becomes INOPEkABLE, reactor operation i .

permissible-for a period of

~~ed- each unit 3 verified 5 days. diesel shall be

~~ thereafter.

OPERABLE

6. From and after the date that the 250-V shutdown board 3EB .

t battery or one of the three 250-V unit batteries and/or its associated .battery board is found to be INOPERABl.E p W-4 M~

for any reason, continued reactor operat'ion is permissible during the succeeding seven days.

Except for routine surveillance testing, the NRC shall be notified, within 24 hours of the situation, the precautions to be taken during this period, and the plans to return the failed component to an OPERABLE state.

7. - When one division of the logic system is INOPERABLE, continued reactor operation's permissible under this condition for seven-days, provided the CSCS requirements listed in

- Specification 3.'9.B.2 are satisfied. The NRC shall be notified withfh 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the situation, the precautions to be taken during this period, and the plans to return the failed-component to an. OPERABLE state.

BFN-Unit 3 3.9/4.9"10

E

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3.9/4.9 AUXILIARY E' RTCAL SY EK LINITIHGCXWDITIOMSPOR OPERATION SURVEILLANCE REQUIRBPGKh S 3.9.A Auxil2arv Electr1cal E u2 ent 4.9.h., Auxiliary Electr2cal System 3.9.A.l.c. (Cont'd) 4.9.A,.l. (Cont'd)

. (2), The 500-kV system is . Once per operating =-

available to the units and 2 shutdown boards l . cycle. a test be conducted will simulating a through the unit" 2 loss of offsite power and stationmervice similar conditions that transformer TUSS 28 with would exist with the no credit taken for the presence of an actual two 500-kV Trinity lines. safety-infection signal If.the unit 1 station- to demonstrate the service transformer is the following:.

second choice, a minimum of two 500-kV lines must (1) Deenergixation of the be available. emergency, buses and load shedding from (3) The Trinity 161-kV line is the emergency buses.

a'vailable to .the units 1 and 2 shutdown boards (2) he diesel starts through both common from ambient station-service condition on the transformers. aut~tart signal, energizes the NOTES PC@ (3): emergency buses with permanently connected (a) If unit 3 is claiming loads. energizes the the Trinity line as an auto-connected offsite source. see emergency loads unit 3 technical through load specifications, section sequencing. and 3.9.A.l.c.2. operates for greater, than or equal to.f"ve (b) If unit 1 ~w.in cold minutes while its shutciown. only one acne ator m~

loaded common station-se.vice with the emeraency

'ransformer is required. loads (4) The Athens 16)-kV line is (3) On diesel aenerator

-. available to the units 1 and 2 shutdown boards breaker t ip loads are shed mom through a ccxiaaon the emergency buses stationmervice and the diesel

'ransformer when unit 1 is o~ rQ cd. bccok~ the auto-in Cold Shutdown and unit -3 reCAOSeS On s~M. signal, the

~w not claiming the Athens emergency buses are line as an offsite source-. energized with

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I 3.9/4 9"2 Rr ~ ~

'~ 2 ar)d 3 1

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ENCLOSURE 2 DESCRIPTION AND JUSTIFICATION BROWNS FERRY NUCLEAR PLANT (BFN)

Descri tion of Chan e Technical specifications 4.9.8.1, 2, 3, 4, 5, -and 6 require the remaining diesel generators and associated boards to be tested "immediately and daily

-thereafter" whenever a diese'1 generator or other. electrical equipment is

.inoperable. Specifications 4.9.8.3 and 4 also require testing of. the Core Spray (CS) System, the low pressure coolant injection, and the 'containment cooling modes of the Residual Heat Removal (RHR) System. This proposed change would require the diesel generators to be demonstrated operable within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and power availability of the associated boards to be verified within one (1) hour and at least once per eight (8) hours thereafter. The revised specifications would not require any additional testing of the Emergency Core Cooling Systems (ECCS).

Technical specification 4.9.A.l.b(3) is changed to correct an editorial error.

Reason for Chan e NRC Generic Letter 84-15, "Proposed Staff Actions to Improve and Maintain Diesel Generator Reliability," recommended that the technical specifications be amended to reduce excessive diesel generator starts due to their adverse effect on reliability. BFN technical specification amendment request 231 dated May 29, 1987 was submitted to implement the recommendations of Generic Letter 84-15. This supplemental response to BFN-TS 231 at the. request of NRC increases the frequency of verification of the associated boards to ensure power availability, reduces excessive testing of the EECS due to its adverse effect on reliability and further reduces required diesel starts.

In reviewing the diesel generator section of the technical specifications, an editorial error was found in technical specification 4.9.A.l.b(3) in that the words "restarts on" should be replaced by "output breaker recloses on."

Justification for Chan e The safety objective of the Standby A-C Power System is to provide a self-contained, highly reliable source of power so that no single credible.

event can disable the core standby cooling functions. or their supporting auxiliaries. Eight generators, (four total shared by units and 2, and four 1

for unit 3) are provided as a standby power supply to be used on loss of the normal auxiliary power system. Each of the diesel generators is assigned primarily to one 4. 16-kV shutdown board. It is possible, through breaker ties to the shutdown buses, to make connections between units 1, 2, and 3 diesel generators allowing for flexibility in load distribution. All ac equipment necessary for the safe shutdown of the plant under accident or nonaccident conditions is fed from this distribution system.

For the long term (greater than 10 minutes), the Standby Power System is designed so that three of the units 1 and 2 diesel generators, paralleled with three unit 3 diesel generators, are adequate to supply all required loads for the safe shutdown and cooldown of all three units in the event of loss of offsite power and a design basis accident in one unit.

A l>

Justification for Chan e (Cont'd)

~ ~

The technical specifications currently contain requirements that have been determined by Generic Letter 84-15 to be-detrimental to the performance of the onsite emergency electrical power system. Therefore, the proposed changes to the technical specification's are to provide'he improvements which are recommended by Generic Letter 84-15 to enhance the. reliability of the diesel generators.

.The current technical speci:fications require that every diesel be tested

."immediately" whenever other power sources are declared inoperable. This requirement subjects the diesel engine to undue wear and stress'n-the engine parts. To be consi'stent with the philosophy-of reducing excessive testing and thereby enhancing the reliability of the diesel generator, TVA proposes that when the other power sources listed'in the technical specifications are declared inoperable, the remaining diesels, be demonstrated operable within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and 'the associated boards verified operable within one hour- and every eight hours thereafter. A 24-hour interval will reduce unnecessary starting.

and stopping of equipment and will'lso=eliminate abusive fast diesel startups and stops that are presently required to test .the diesels immediate.ly.. The associated boards will be verified by verifying correct breaker alignment and indicated power availability. The increased verification frequency on the associated electr) cal boards wi 1 1 provide verification of avail'ability and not adversely effect equipment or significantly consume operator time, since these

. survei llances can -be performed from the main control room without actuating.

any mechanical equipment. These changes are consistent with, the ties guidance given in Generic Letter 84-15.

Deleting the conditional testing of the RHR and CS Systems when an electrical component fails will not reduce'safety since failures. experienced in one train of the electrical system 'have no mechanistic connection with performance of operable equipment supplied by other sources of electrical power. Such testing may be detrimental to reliability and avai labi 1:i ty. due to excessive equipment starts, and .test produced failures and unavai labi li .

. Furthermore, significant operator attention must be devoted to running these tests and realigning the system after the test. The increased surveillance. of the associated boards wi 11 provide additional assur'ance that power will be

.available to this'quipment if needed, without effecting the equipment or power supply.-

A related change being corrected as part of this amendment is 'an editorial error on technical specification 4.9.A.1(3)'. Final-Safety Analysis Report section 8.5.5-correctly states that .if an accident occurs during a diesel test the diesel output breaker trips but the diesel remains running and available for service. The technical specification.surveillance requirement incorrectly states that the d.iesel restarts.

The proposed changes to BFN units 1, 2, and 3 Technical Specifications are consistent with Generic Letter 84=15. They provide positive improvements to diesel generator reliability.. For these reasons, TVA has concluded that the

. proposed changes to the technical specifications will not reduce the margin of plant safety.