ML20117D165

Proposed Tech Specs of SQN Units 1 & 2,deleting Table 4.8.1, DG Reliability, & Revising Section 3.8.1 to Allow Once Per 18 month,7 Day AOT for EDGs

ML20117D165
Person / Time
Site:	Sequoyah
Issue date:	08/22/1996
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20117D099	List: ML20117D092 ML20117D165
References
NUDOCS 9608280187
Download: ML20117D165 (32)

Text

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s 1

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ENCLOSURE 1 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SON-TS-96-08)

UST OF AFFECTED PAGES Unit 1 3/4 8-1 3/4 8-3 3/4 8-7 3/4 8-7b B 3/4 8-1 Unit 2 3/4 8-1 l 3/4 8-3 1 3/4 8-8 3/4 8-8b i B 3/4 8-1 l 9608280187 960822 PDR P

ADOCK 05000327 PDR-i

.)

3/4.8 ELECTRICAL POWER SYSTEMS I l

3/4.8.1 A.C. SOURCES '

) OPERATING  ;

LIMITING CONDITION FOR OPERATION 3.8.1.1 As a minimum, the following A.C. electrical power sources shall be OPERABLE:

g a. Two physically independent circuits between the offsite transmission network and the onsite Class IE distribution system, and M b. Four separate and independent diesel generator sets each with:

1. Two diesels driving a common generator

2. Two engine-mounted fuel tanks containing a minimum volume of 250 gallons of fuel, per tank 9 3. A separate fuel storage system containing a minimum volume of g 62,000 gallons of fuel,

> 4. A separate fuel transfer pump, and

5. A separate 125-volt D.C. distribution panel,125-volt D.C.

battery bank and associated charger.

) APPLICABILITY: MODES 1, 2, 3 and 4.

.' gg ' '

$ a. With one offsite A.C. circuit of the above required A.C. electrical power sources inoperable, demonstrate the OPERABILITY of the remain. R209 ing offsite A.C. circuit by performing Surveillance Requirement 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter.

6 Restore at least two offsite circuits to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

R209 b.d@With diesel generator set (s) 1A-A and/or 2A-A or 18-B and/or 2B-B of the above required A.C. electrical power sources inoperable, demon-strate the OPERABILITY of the remaining A.C. sources by performing Surveillance Requirement 4.8.1.1.1.a w' thin one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and determining OPERABLE diesel genera- R209

% ks tor sets are not inoperable due to common cause failure or performing Surveillance Requirement 4.8.1.1.2.a.4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; restore at dAFN least four diesel generator sets to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

• or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD gi41 1

SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. l

• The 72-hour action statement may be extended for an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for one train of diesel generators (either IA-A and 2A-A, or IB-B and.2B-B) during R141 '

the performance of Surveillance Requirement 4.8.1.1.2.f.l. A temporary fuel supply must be connected to the diesel generator set that is having the associated fuel tanks cleaned.

1. Required actions, to verify OPERABLE diesel generator sets are not inoperable R209 l due to common cause failure or perform SR 4.8.1.1.2.a.4, shall be completed if -

this action is entered.

June 29, 1995 SEQUOYAH - UNIT 1 3/4 8-1 AmendmentNo.g, 132, 137,

I ELECTRICdL" POWER SYSTEMS -

I 1

h v SURVEILLANCE REOUIREMENTS 'fContinued)

)

4.8.1.1.2 Each diesel generator set shall be demonstrated OPERABLE: *

a. hWhdvtsu

ccerde,;

rith th.-p :;mney3/

fr m . L8 A d'yacified CG.

, T: M. 4. m 1 i,,, .AWW h '. ,

I

{ T "_^ Fi b ;;.:,; r,A:TE by:

3 i

4

1. Verifying the fuel level in the engine-mounted day. tanks. -

j

2. Verifying the fuel level in the 7 day tank.

3. Verifying the fuel transfer pump can be started and transfers fuel from the storage system to the engine mounted fuel tanks.

g19,

4.

• Verifying the diesel starts from ambient condition and achieves in less than or equal to 10' seconds generator voltage and frequency of 6900 i 690 volts and 60 i 1.2 Hz. The diesel generator shall be started for this test by using one of the following' signals with startup on each signal verified at least R56 once per 124 days:

a) Manual.

b) Simulated loss of offsite power by itself. R56 c) An ESF actuation test signal by itself.

[' 5.

• Verifying the ge5ratir'is synchronized, loaded ' bet' ween 396'0'kw R177 and 4400 kw in less than or equal to 60 seconds, and operates for greater than or equal to 60 minutes, and ,

6. Verifying the diesel generator is. aligned to provide standby power to the associated shutdown boards.

b. At letst once per 31 days and after each operation of the diesel where the period of operation was greater than or equal to I hour by checking for and removing accumulated water from the engine-mounted fuel tanks.

c. At least once per 92 days, and from new fuel oil prior to addition to the 7-day tanks by verifying that a sample obtained in accordance with ASTM-D270-1975 has a water and sediment content of less than or '

equal to .05 volume percent and a kinematic viscosity 9100*F of greater than or equal to 1.8 but less than or equal to 5.8 centi-stokes when tested in accordance with ASTM-D975-77, and an impurity level of less than 2 mg. of insolubles per 100 al. when tested in accordance with ASTM-D2274-70.

• The diesel generator start (10 sec) and load (60 sec) from standby conditions RS6 l shall be performed at least once per 184 days in these surveillance tests. I All other diesel generator engine starts and loading for the purpose.of this )

surveillance testing may be preceded by an engine idle start, followed by Ris9 gradual acceleration to synchronous speed (approximately 900 rpm), '

1 synchronization, and gradual loading. )

l SEQUOYAH - UNIT 1 3/4 8-3 Amendment No. 52,64,99,109,  ;

137,173' 195 l February 9, 1995

i l

TABLE 4.8-1 DIESEL GENERATOR RELIABILITY of Failures in No. of Failures in l

. lastNO valid tests

• 1ast 100 valid tests

• Reliability Actions I 1

Test at least once per days 12 -

Test at least once r 7 days **

3 6 Within 30 days epare a report for NRC audit in accordance with Sectio 6.9.2.2.

5 11 Declare e diesel generator ,

inopera e and perform a re- l qualif cation test for the l affe ed diesel generator pu uant to the attachment t this table.

l A) ~

l RS6 l

• Criteria for determinin umber of failures and number of lid tests shall be in accordance with gulatory Position C.2.e of Regulator Guide 1.108, Revision 1, August 7, where the number of tests and failur are determined l on a per diesel erator unit basis. For the purposes of this test schedule '

only valid tes conducted after the Operating License' issuance te shall '

be included the computation of the "last 20 valid tests." Entr into this test sched e shall be made at the 31-day test frequency.

• • This t s frequency shall be maintained until seven consecutive failu free de have been performed and the number of failures in the last 20 v lid  ;

d nds has been reduced to one or less. '

o-3- 4 esu b dl y b

Fe6~ruary 3 1987 SEQUOYAH - UNIT 1 3/4 8-7 Amendment No'. 52

/

ATTACHMENT TO TABLE 4.8-1 DIESEL GENERATOR REQUALIFICATION PROGRAM

. (1 Perform seven consecutive successful demands without a failure with 0 days of diesel generator being restored to operable status and 1\ consecutive successful demands without a failure within 75 d s of.

die 1 generator being resteired to operable status.

(2) If a fa ure occurs during the first seven tests in the re alification test progP m, perform seven successful demands without a additional failure wit n 30 days of diesel generator of being res cred to operable statiss and I onsecutive successful demands without failure within 75 days of bein restored to operabic status.

(3) If a failure occurs during the second seven tes (tests 8 through

14) of^(1)~above, pe ,orm 14 consecutive succe sful demands without an

additional failure wit' n 75 days of the fai re which occurred during

, the requalification test .

,c wm . -

l (4) Following the second failure uring th requalification test program, be in at least HOT STANDBY within he ne 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

(5) Duribgiidii[1hfibation'tNiing se d sel generator should not be tested more frequently than at 24-ho interv s.

After a diesel generator has be successfully qualified, sub'equent s repeated RS6

V/ requalification tests will no e required for th diesel generator under the following conditions

(a) Thenumbefof"failu s;in the last 20 valid deman is less than 5.

(b) The number of f ures in the last 100 valid demands less than 11.

i- (c) In the event hat following successful requalification of diesel generator, the number f failures is still in excess of the remedial ac ion criteria (a and/or above) the following exception will be allowed unt'l the diesel genera r is no longer in violation of the remedial action crite ia (a and/o b above).

Requalj ication' testing will not be required provided that after each vali dema p the number of failures in the last 20 and/or 100 valid demands has no increased l Once the diesel generator is no longer in violation of the remedia g a tion criteria above the provisions of those criteria alone will prevail. \N s

N

/

j February 3 1987 SEQUOYAH - UNIT 1 3/4 8-7b Amendment o. 52 l

s

3/4.8 ELECTRI. CAL POWER SYSTEMS BASES 3/4.8.1 and 3/4.8.2 A.C. SOURCES AND ONSITE POWER DISTRIBUTION SYSTEMS The OPERABILITY of the A.C. and D.C power sources and associated distri-bution systems during operation ensures that sufficient power will be available to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of accident conditions within the facility. The minimum specified independent and redundant A.C. and D.C. power sources and distribution systems satisfy the requirements of General Design f Criteria 17 of Appendix "A" to 10 CFR 50.

i I

i The ACTION requirements specified for the levels of degradation of the

! power sources provide restriction upon continued facility operation commensur-l ate with the level of degradation. The OPERABILITY of the power sources are l

consistent with the initial condition assumptions of the accident analyses and j j are based upon maintaining at least one redundant set of onsite A.C. and D.C.

power sources and associated distribution systems OPERABLE during accident i conditions coincident with an assumep loss of offsjte weg and single failure h of the other onsite A.C. source. 6 'An gg *W f

k m. fee ( Aco ' i

l. M M A @ @t_ day' la A l The footnote for Action b of C03.8.1.1(requirescompletionofaAsfM 209 l j

4 determination that the OPERABLE diesel generators are not inoperable due to common cause failure or performance of Surveillance 4.8.1.1.2.a.4 if Action b j

y is entered. The intent is that all diesel generator inoperabilities must be investigated for common cause failures regardless of how long the diesel j{'- generator inoperability persists.

The action to determine that the OPERABLE diesel generators are not jl inoperable due to common cause failure provides an allowance to avoid unnecessary testing of OPERABLE diesel generators. If it can be determined that i the cause of the inoperable diesel generator does not exist on the OPERABLE i

diesel generators, Surveillance Requirement 4.8.1.1.2.a.4 does not have to be 4 performed. If the cause of inoperability exists on other diesel generator (s),

i the other diesel generator (s) would be declared inoperable upon discovery and i Action e of LCO 3.8.1.1 would be entered as applicable. Once the common failure is repaired, the common cause no longer exists, and the action to determine inoperability due to common cause failure is satisfied. If the cause of the

- initial inoperable diesel generator cannot be confirmed not to exist on the i remaining diesel generators, performance of Surveillance 4.8.1.1.2.a.4 suffices j to provide assurance of continued OP.ERABILITY of the other diesel generators.

i According to Generic Letter 84-15, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that j the OPERABLE diesel generators are not affected by the same problem as the inoperable diesel generator.

1 Additional' ACTION requirements are specified for performance of the g141

) chemical cleaning required by Surveillance Requirement 4.8.1.1.2.f.1. The i motor-driven fuel pumps for the diesel generator set with the tanks being i cleaned will be temporarily connected to the underground storage tanks for the j other diesel generator set with the same train designation. An additional j fuel-oil inventory of approximately 68,000 gallons will be available in one of i I

June 29, 1995 l Amendment No. 12, 137, 173, l SEQUOYAH - UNIT 1 B 3/4 8-1 205 j

'_3/4.8 ELECTRICAL POWER SYSTEMS i

3/4.8.1 A.C. SOURCES

] OPERATING ,.

LIMITING CONDITION FOR OPERATION

\. 3.8.1.1 As a minimum, the following A.C. electrical power sources shall be g OPERABLE:

$ a. Two physically independent circuits between the offsite transmission ,

E network and the onsite Class 1E distribution system, and '

" b. Four separate and independent diesel generator sets each with: l 7 1. Two diesels driving a common generator  !

h i

2. Two engine-mounted fuel tanks containing a minimum volume of 250  ;

4 gallons of fuel, per tank l 3 3. A separate fuel storage system containing a minimum volume of

'd 62,000 gallons of fuel, E

4. A separate fuel transfer pump, and

.$ 5. A separate 125-volt D.C. distribution panel,125-volt D.C. l g- battery bank and associated charger.

, :E i

g PPLICABILITY: MODES 1, 2, 3 and 4.

ACTION: R195 i

• g a. With one offsite A.C. circuit of the above required A.C. electrical

)

h-A power sources inoperable, demonstrate the OPERABILITY of the remain-ing offsite A.C. circuit by performing Surveillance Requirement i 1 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter.

U Restore at least two offsite circuits to OPERABLE status within l

$ 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in~ '

& COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

R195 !

tg b.#OWith diesel generator set (s) 1A-A and/or 2A-A or IB-B and/or 2B-B of l the above required A.C. electrical power sources inoperable, i p demonstrate the OPERABILITY of the remaining A.C. sources by Je-f performing Surveillance Requirement 4.8.1.1.1.a within one hour and R195 tJ gf r-at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and determining OPERABLE diesel generator sets are not inoperable due t~ocommon cause failure or performing Surveillance Requirement 4.8.1.1.2.a.4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />;

! 03 restore at least four diesel generator sets to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

• or be in at least H0T STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and

~

R123

in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

@ *The 72-hour, action statement may be extended for an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for one train of diesel generators (either IA-A and 2A-A, or IB-B and 2B-B) during the performance of Surveillance Requirement 4.8.1.1.2.f.1. A temporary fuel supply must be connected to the diesel generator set that is having the Q..

%I- associated fuel tanks cleaned.

R195 4 # Required actions, to verify OPERABLE diesel generator sets are not inoperable due to common cause failure or perform SR 4.8.1.1.2.a.4, shall be completed if this action is entered. June 29, 1995 3/4 8-1 Amendment No. 89, 119, 123,

, SEQUOYAH - UNIT 2 195

. o ELECTRICAL POWER SYSTEMS I( 7' SURVEILLANCE REOUIREMENTS (Continued) l 4.8.1.1.2 Each diesel generator set sh 11 be demonstrated OPpE BLE: . l a.

/4t Ag ofuut PV W 95 m a NG Ir accer m e w dA the frequency specifickin T:ble '.8-1 *d en bcsw

by, STAGGERtu TEu unsis Dy:

1. Verifying the fuel level in the engine-mounted day tanks.

~

.2. Verifying the fuel level in the 7 day tank.

3. Verifying the fuel transfer pump start's and transfers fuel from l the storage system to the engine mounted fuel tanks. .

! 4.

• Verifying the diesel starts from ambient condition and achieves R185 in less than or equal to 10 seconds generator voltage and frequency of 6900 i 690 volts and 60 i 1.2 Hz. The diesel generator shall be started for this test by using one of the gg9 following signals.with startup on each signal verified at least

once per 124 days:

1 a) Manual.

b) Simulated loss of offsite power by itself. g44 c) An ESF actuation test signal by itself.

,1 5.

• Verifying the generator is synchronized, loaded between 3960 kw R164 l and 4400 kw in less than or equal to 60 seconds, and operates for i greater than or equal to 60 minutes, and

6. .

Verifying the diesel generator is aligned to provide standby power j to the associated shutdown boards.

) b. At least once per 31 days 'and after each operation of the diesel where the period of operation was greater than or equal to I hour by checking

for and removing accumulated water from the engine-mounted fuel tanks.

c. At least once per 92 days and from new fuel oil prior to addition to the 7-day tanks by verifying that a sample obtained in accordance with ASTM-D270-1975 has a water and sediment content of less than or equal to .05 volume percent and a kinematic viscosity 9100*F of greater than or equal to 1.8 but less than or equal to 5.8 centistokes when tested in accordance with ASTM-D975-77, and an impurity level of less than 2 mg. of insolubles per 100 ml. when tested in accordance with ASTM-D2274-70.

• The diesel generator start (10 sec) and load (60 sec) from standby conditions l shall be performed at least once per 184 days in these surveillance tests. R44 i All other diesel generator engine starts and loading for the purpose of this l g surveillance testing may be preceded by an engine idle start, followed by R 86 4 gradual acceleration to synchronous speed (approximately 900 rpm),

synchronization, and gradual loading. j SEQUOYAH - UNIT 2 3/4 8-3 Amendment No. 44,56,88,99, February 9, 1995 123,164, 186 i l

J

1 s

TABLE 4.8-1

,. DIESEL GENERATOR RELIABILITY

. of Failures in No. of Failures in la 20 valid tests

• 1ast 100 valid tests

• Reliability Actions

<1 -

Test at least once er 31 days

2. Test at least o e per 7 days **

3 6 Within 30 da s prepare a report for NRC au t, in accordance with Sec on 6.9.2.2. l 5 11 Decla the diesel generator ino rable and perform a re- l qu ification test for the I fected diesel generator ,

pursuant to the attachment to this table.

R44

• Criteria for determi ng number of failures and numb r of valid tests shall be in accordance wi Regulatory Position C.2.e of Re latory Guide 1.108, Revision 1, Augus 1977, where the number of tests and ilures are determined i on a per diesel enerator unit basis. For the purposes o this test schedule only valid tes) conducted after the Operating License issu ce date shall

' be included 4 the computation of the "last 20 valid tests." Entry into this test sched e shall be made at the 31-day test frequency.

• • This tes frequency shall be maintained until seven consecutive f lure free demand have been performed and the number of failures in the last valid deman s has been reduced to one or less.

February 3 I SEQUOYAH - UNIT 2 3/4 8-8 Amendment N,o. g7

-f

ATTACHMENT TO TABLE 4.8-1 DIESEL GENERATOR REQUALIFICATION PROGRAM N(1Perform seven consecutive successful demands without a failure with' 0 days of diesel generator being restored to operable status and consecutive successful demands without a failure within 75 d s of di el generator being restored to operable status. >

(2) If a f lure occurs during the first seven tests in the re alification test pro am, perform seven successful demands without a additional failure status and w1 in 30 days of diesel generator of being re ored to operable 75 days of be consecutive successful demands without restored to operable status.

failure within (3) If a failure occu during the second seven tes (tests 8 through

14) of (1) above, p form 14 consecutive succ sful demands without an additional failure w in 75 days of the fa ure which occurred during the requalification tes ing. i' (4) Following the second failu during th requalification test program, be in at least HOT STANDBY with the n t 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. i l

(5) ~During requalification testing e Iesel generator should not be tested more frequently than at 24-ho inte vals.

After a diesel generator has b en successful requalified, subsequent repeated requalification tests will no be required for hat diesel generator under the {

following conditions: R4 P..

Lq.y (a) The number of fail es in the last 20 valid de ds is less than 5. ~

(b) .The number of f lures in the 1 st 100 valid deman is less than 11.

t (c) "In'~he even that following successful requalification f a diesel generator, the number of failures is still in excess of the remedia action criteria (a and/o b above) the following exception will be allowe ntil the diesel genera r is no longer in violation of the remedial action iteria (a and/ b above). _

Requal fication testing will not be required prov'ided that after each glid dema inc eased. the number of failures in the last 20 and/or 100 valid demands haA not Once the diesel generator is no longer in violation of the rem' ial tion criteria above the provisions of those criteria alone will prevail.

ag & .

February 3 1987 SEQUOYAH - UNIT 2 3/4 8-8b Amendment N,o. 44 1 ,

[s

. , i JD -

3/4.8 ELECTRICAL POWER SYSTEMS BASES 3/4.8.1 and 3/4.8.2 A.C. SOURCES AND ONSITE POWER DISTRIBUTION SYSTEMS j i

The OPERABILITY of the A.C. and D.C power sources and associated distri-  !

bution systems during operation ensures that sufficient power will be available j to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of accident conditions within the facility. The minimum specified independent and redundant A.C. and D.C. power  !

sources and distribution systems satisfy the requirements of General Design i Criteria 17 of Appendix "A" to 10 CFR 50.

The ACTION requirements specified for the levels of degradation of the l power sources provide restriction upon continued facility operation commensur-  !

ate with the level of degradation. The OPERABILITY of the power sources are consistent with the initial condition assumptions of the accident analyses and are based upon maintaining at least one redundant set of onsite A.C. and D.C.

power sources and associated distribution systems OPERABLE during accident conditions coincident with an assumed loss of offsite powe and single failure A

72 j c4owet dd  !

oftheotheronsitb.C.

4hn- to 2de^ 5source.Eyg1'u c.4ccq m b wcc.

, Aeg M . R195 The footnote for Action b of LCO 3.8.1.1 requires completion of a determination that the OPERABLE diesel generators are not inoperable due to common cause failure or performance of Surveillance 4.8.1.1.2.a.4 if Action b

• )

is entered. The intent is that all diesel generator inoperabilities must be investigated for common cause failures regardless of how long the diesel generator inoperability persists.

The action to determine that the OPERABLE diesel generators are not inoperable due to common cause failure provides an allowance to avoid unnecessary testing of OPERABLE diesel generators. If it can be determined that the cause of the inoperable diesel generator does not exist on the OPERABLE diesel generators, Surveillance Requirement 4.8.1~.1.2.a.4 does not have to be performed. If the cause of inoperability exists on other diesel generator (s),

the other diesel generator (s) would be declared inoperable upon discovery and

. Action e of LCO 3.8.1.1 would be entered as applicable. Once the common failure is repaired, the common cause no longer exists, and the action to determine inoperability due to common cause failure is satisfied. If the cause of the initial inoperable diesel generator cannot be confirmed not to exist on the remaining diesel generators, performance of Surveillance 4.8.1.1.2.a.4 suffices to provide assurance of continued OPERABILITY of the other diesel generators.

According to Generic Letter 84-15, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that the OPERABLE diesel generators are not affected by the same problem as the inoperable diesel generator.

Additional ACTION requirements are specified for performance of the R123 chemical cleaning required by Surveillance Requirement 4.8.1.1.2.f.1. The motor-driven fuel pumps for the diesel generator set with the tanks being Gg cleaned will be temporarily connected to the underground storage tanks for the E other diesel generator set with the same train designation. An additional fuel-oil inventory of approximately 68,000 gallons will be available .in one of '

the yard storage tanks prior to the start of the chemical cleaning of any June 29 ,1995 B 3/4 8-1 Amendment No. 123, 164, SEQUOYAH - UNIT 2 195

s l ENCLOSURE 2 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SON-TS-96-08) i DESCRIPTION AND JUSTIFICATION FOR REMOVAL OF THE ACCELERATED TESTING REQUIREMENTS FOR THE  !

EMERGENCY DIESEL GENERATORS (EDGs)

IN ACCORDANCE WITH GENERIC LETTER (GL) 94-01 AND I l

TO REVISE THE EDG ALLOWED OUTAGE TIME (AOT)

TO ALLOW A ONCE PER 18 MONTH,7-DAY AOT FOR PLANNED MAINTENANCE ACTIVITIES 5

.Descriotion of the Proposed Chanae TVA proposes to remove the accelerated testing requirements.for the EDGs in

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accordance with GL 94-01, " Removal of Accelerated Testing and Special Reporting Requirements for Emergency Diesel Generators from Plant Technical Specifications."

. This change would require revising:

1. Page 3/4 8-3, Step 4.8.1.1.2.a from "In accordance with the frequency specified in Table 4.8-1 on a STAGGERED TEST BASIS by:," to "At least once per 31 days on a staggered test basis by:,"

2. Unit 1,' delete the actual table on page 3/4 8-7. This page will be replaced with a blank page stating, "This page intentionally deleted."

3. Unit 2, delete the actual table on page 3/4 8-8. This page will be replaced with a blank page stating, "This page intentionally deleted."

4. Unit 1, delete the associated notes on page 3/4 8-7b. This page will be replaced with a blank page stating, "This page intentionally deleted."

5. Unit 2, delete the associated notes on page 3/4 8-8b. This page will be replaced with a blank page stating, "This page intentionally deleted."

TVA is also proposing to revise the SON Units 1 and 2 TSs to allow a once per 18 month,7-day AOT for planned maintenance activities. This change would require revising page 3/4 8-1 by adding an "@" symbol to Step b of the Action statement, and also add at the "@" symbol, the statement, "The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement may be extended to 7 days once per 18 months for planned diesel generator maintenance."

Page B 3/4 8-1 of the Bases will also be revised by adding, " Extension of the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed LCO time to seven days is a recognition of maintenance time requirements.",

to the end of the second paragraph.

Reason for the Proposed Chance I TVA proposes deleting the accelerated testing required in Table 4.8-1 in accordance with GL 94-01. This letter was issued to advise licensees that they may request a license amendment to remove accelerated testing and special reporting requirements j for EDGs from plant TS based on a commitment to implement the provisions of ,

10 CFR 50.65 and guidance of Regulatory Guide 1.160.

TVA also proposes changing the AOT in TS 3.8.1, "A.C. Sources," Operating, for one unavailable EDG from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days once every 18 months. The SON five-year  ;

schedule shows that EDG maintenance is conducted every 9 months, and in 1999, the EDGs must undergo a major 12-year maintenance. Since the scope of that effort j is substantially larger, a longer AOT will reduce the number of additional entry into i limiting condition for operation (LCO) action statements required to complete this effort and reduce the overall EDG unavailability.

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This change is also being submitted to the NRC as a Cost Beneficial Licensing l Amendment (CBLA). This change will not adversely impact safety and will permit l flexibility in performing preventive maintenance on the EDGs during power operation.

This represents a potential savings of $6,000,000cver the remaining life of SON. I Justification for the Prooosed Chanae l Deletion of Table 4.8-1 and the associated notes is justified because SON has met the requirements of GL 94-01. SON has established a EDG target reliability of 0.975 in accordance with 10 CFR 50.63, " Loss of All Alternating Current," or the station blackout rule, and has implemented the requirements of 10 CFR 50.65,  !

" Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power I Plants." The methodology for implementing the rule is provided in NUMARC 93-01, i

" Industry Guidelines for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," dated May of 1993. The rule requires that ':tructures, systems, and components (SSC) be monitored against establiAd ) erformance criteria or goals. In performing monitoring or maintenance activities, which require taking equipment out of service, utilities are required to assess the overall effect and increased risk on the performance of safety functions.

TVA also proposes to extend the current AOT from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days once every 18 months. This would significantly reduce the EDG unavailability time for  ;

maintenance annually. Additionally, it would increase the margin between LCO AOT l and the scheduled maintenance time. A 7-day AOT would also be consistent with the objective and intent of 10 CFR 50.65, Appendix A, "The Maintenance Rule." Without this AOT extension, it will be difficult to perform the upcoming 12-year EDG maintenance with either unit on line. The duration of work could extend for over 2,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />.with 32 LCO action statement entries. With the 7-day AOT, the calendar duration of required maintenance would be significantly reduced.

The electrical system design is described in Section 8.0, " Electrical Power," in the SON Final Safety Analysis Report (FSAR). SON is connected to a strong offsite transmission network. In the vicinity of SON, the lines are on right of ways which are sufficiently wide enough to preclude the likelihood of a failure of one line causing failure of the other line. Electric power to SON is supplied by two physically and electrically independent circuits from the Sequoyah 161-kV switchyard through three separate transformers to the onsite electrical distribution system. The 161-kV switchyard is designed with two main bus sections and is arranged so that the supply to the onsite power system, as well as the connections to the generator and the 500-161 kV transformer bank, is maintained to one bus section for a failure of the other section. Four 161-kV lines terminate on one bus, and four other 161-kV lines terminate on the other bus. Two fuseless 84 MVAR 161-kV capacitor banks are tied to the 161 kV switchyard through double bus-tie breakers. Each bank is independently switched. These capacitors provide reactive voltage support for the 161-kV offsite system.

This change is also being submitted to the NRC as a Cost Beneficial Licensing Amendment (CBLA). This change will not adversely impact safety and will permit

• flexibility in performing preventive maintenance on the EDGs during power operation.

This represents a potential savings of $6,000,000 cver the remaining life of SON.

Justification for the Proposed Chance ,

Deletion of Table 4.81 and the associated notes is justified because SON has met the requirements of GL 94-01. SON has established a EDG target reliability of 0.975 in accordance with 10 CFR 50.63," Loss of All Alternating Current," or the station blackout rule, and has implemented the requirements of 10 CFR 50.65,

" Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." The methodology for implementing the rule is provided in NUMARC 93-01.

The rule requires that structures, systems, and components (SSC) be monitored against established performance criteria or goals. In performing monitoring or maintenance activities, which require taking equipment out of service, utilities are required to assess the overall effect and increased risk on the performance of safety functions.

TVA also proposes to extend the current AOT from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days once every 18 months. This would significantly reduce the EDG unavailability time for maintenance annually. Additionally, it would increase the margin between LCO AOT and the scheduled maintenance time. A 7-day AOT would also be consistent with the objective and intent of 10 CFR 50.65, Appendix A, "The Maintenance Rule." Without  !

this AOT extension, it will be difficult to perform the upcoming 12 year EDG maintenance with either unit on line. The duration of work could extend for over 2,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> with 32 LCO action statement entries. With the 7-day AOT, the calendas duration of required maintenance would be significantly reduced.

t- The electrical system design is described in Section 8.0, " Electrical Power," in the SON Final Safety Analysis Report (FSAR). SON is connected to a strong offsite transmission network. In the vicinity of SON, the lines are on right of ways which are sufficiently wide enough to preclude the likelihood of a failure of one line causing failure of the other line. Electric power to SON is supplied by two physically and electrically independent circuits from the Sequoyah 161-kV switchyard through three separate transformers to the onsite electrical distribution system. The 161-kV switchyard is designed with two main bus sections and is arranged so that the supply to the onsite power system, as well as the connections to the generator and the 500-161 kV transformer bank, is maintained to one bus section for a f ailure of the other section. Four 161-kV lines terminate on one bus, and four other 161-kV lines terminate on the other bus. Two fuseless 84 MVAR 161-kV capacitor banks are tied to the 161-kV switchyard through double bus-tie breakers. Each bank is independently switched. These capacitors provide reactive voltage support for the 161-kV offsite system.

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.. 3 Several improvements to the plant / grid interfaces at SON have been made since the 72-hour AOT was established. They include:

1. Replacing the common station service transformers (CSSTs) with ones having automatic high-speed onload voltage tap changers in order to maintain optimal voltages to the safety-related system while connected to the preferred power supply (PPS) and during all modes of plant startup, shutdown, and operation.

With the installation of these new transformers, the in-plant auxiliary power system can accommodate a transmission system bandwidth of +/-5% of nominal versus a 1-2% bandwidth before.

2. SON has implemented a design change which provides for the in-plant alternating current auxiliary power system to be normally fed from the PPS during all modes ,

of plant operation, startup, and shutdown. This increases reliability by reducing j plant transfers during a plant shutdown and provides better voltage regulation to '

the safety-related boards during all modes of plant operation. i

3. SON installed two 84 MVAR capacitor banks outside the 161-KV switchyard to I l

provide reactive power support to the plant during a Unit 2 trip and shutdown.

4. Transmission Power Systems is performing comprehensive Transmission System Studies for all TVA nuclear plants on a three-year cycle. These studies include load flow analyses and transient stability studies and are performed in accordance with the guidelines in IEEE 765-1995 for transmission system studies. This verification ensures that SON can withstand a design-basis accident with a preexisting problem in one of the two qualified offsite power lines.

1 Preferred power to SON is supplied by either of the 161-kV buses to three CSSTs.

The CSSTs supply power to the four start buses (SBs), and the four SBs supply power-to the eight unit boards. There are four unit boards per unit and the unit boards supply power to the four shutdown boards, there are two shutdown boards per unit.

Each of the shutdown boards supply a single train of safe shutdown equipment along with some common equipment. The shutdown boards can also be supplied emergency power by seismic, environmentally qualified EDGs that supply backup power to the vital 6.9-kV, and 480-V busses in the event of a loss of normal and alternate offsite power.

During power operation, the EDGs help to ensure that sufficient power will be available to the safety-related equipment, which is needed for the safe shutdown of the plant and for mitigation and control during accident conditions. During shutdown 4 and refuelling conditions, the EDGs help to ensure that the facility is able to maintain shutdown or refueling conditions for extended periods of time.

SON EDGs have high availability and reliability ratings. For implementation of 10 CFR 50.63, SON established a EDG target reliability of 0.975. As of March 1992, the SON EDGs each had an average reliability of 0.999 and SON has continued to demonstrate high EDG performance. SON EDG unavailability for 1994 was 0.017; for 1995,0.015; and for 1996, the year-to-date value is 0.008. These values are well below the year 2000 industry goal of 0.025.

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SON's EDG configuration is such that four of four EDGs are required to be operable to operate one unit (except under LCO action statement conditions). Since it is not practical to schedule outages of both units simultaneously, EDG maintenance must be done at power under LCO conditions for at least one unit.

SON routinely carries out scheduled planned maintenance on the EDGs during power operation. Planned maintenance for the EDGs are conducted on schedules that include daily, weekly, prestart, monthly, quarterly, once-per-refuel cycle, every 36 months, every 72 months, and every 12 years. The activities are as simple as checking the oil level to as complicated as engine rebuilding. The activities performed on the 18 month and longer schedules require the EDG to be removed from service.

Experience has shown that, even with careful planning, maintenance duration sometimes approaches the current 72-hour AOT. In order to accommodate ,

unanticipated problems, SON has developed the practice of scheduling work for only 50 to 60 percent of the AOT. In order to meet the EDG TS requirements, SON divides the EDG maintenance into a serios of smaller increments which car' be completed in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Each smaller maintenance effort requires tag out, testing, and tag lifting and EDG testing. The cumulative effect is an additional 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> of EDG unavailability during each smaller scope maintenance effort. The EDG unavailability, with the current 72-hour AOT, is significantly greater than it would be with a 7-day outage time, it is estimated that the 7-day AOT would reduce EDG unavailability about 17 percent for the maintenance work done annually and about 50 percent for the upcoming 12-year maintenance (1999). Additionally, the difference between hours of scheduled work, and the total AOT hourc, increases with the 7-day AOT. This increase would also redu .s the likelihood of an unanticipated problem causing the

. AOT to be exceeded a ssulting in a forced shutdown of both units.

The expected EDG Lnavailability under the current maintenance schedule with the 72-hour AOT is 576 hours0.00667 days <br />0.16 hours <br />9.523809e-4 weeks <br />2.19168e-4 months <br /> per EDG per year. This will result in a core damage frequency (CDF) of 3.9364E-5. With the 7-day AOT, the EDG unavailability will be 336 hours0.00389 days <br />0.0933 hours <br />5.555556e-4 weeks <br />1.27848e-4 months <br /> per EDG per year, with a CDF of 3.8482E-5.

The risk associated with shutdown operations will not change due to this requested change. At SON, the shutdown risk philosophy is based on a defense in depth approach. This approach requires TS plus one availability without plant management approval. Outage scheduling flexibility willimprove if the EDGs are not required to be out of service during an outage. Other surveillance testing and maintenance will be easier to schedule with improved EDG availability during outages. Refueling outage l activities will be more efficient and shutdown risk will be reduced. -

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Environmental Impact Evaluation The proposed change does not involve an unreviewed environmental question because operation of SON, in accordance with these changes, does not cause a change in the type of or significant increase in the amounts of any effluent that may be released offsite, or a significant increase in the individual or cumulative occupational radiation exposure. The proposed change meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), an environmental assessment of the proposed change is not required.

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a ENCLOSURE 3 PROPOSED TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SON-TS-96-08)

)

i DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION l

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2 Significant Hazards Evaluation i  !

! TVA has evaluated the proposed technical specification (TS) change and has

' determined that it does not represent a significant hazards consideration based on

criteria established in 10 CFR 50.92(c). Operation of Sequoyah Nuclear Plant (SON) in 1 j accordance with the proposed amendment will not:

I i 1. Involve a significant increase in the probability or consequences of an accident previously evaluated.

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Deletion of Table 4.8-1,in accordance with Generic Letter (GL) 94-01,is an administrative change that will not impact the plant design or operation. None of

the assumptions used in evaluating the radiological consequences of an accident f are changed. A new or altered release path is not created. Therefore, this change does not involve an increase in the probability of any accident previously l j; evaluated.

4

- The emergency diesel generators (EDGs) supply backup power to the essential safety systems in the event of a loss-of-offsite (normal) power. The EDGs cannot j- initiate an accident. The requested change will not impact the plant design or operation. Th'e increased out of service time does not invalidate assumptions used in evaluating the radiological consequences of an accident and does not

provide a new or altered release path. Therefore, this change does not involve an increase in the probability of any accident previously evaluated. 1

- I i An increase in the allowed outage time (AOT) would not change the conditions, )

[

operating configuration, or minimum amount of operable equipment assumed in I the plant Final Safety Analysis Report for accident mitigation. The longer AOT would provide a longer time window for maintenance, but would lesson the total )

EDG unavailability per year. Based on the smallincrease in plant risk during i maintenance, and the decrease in overall plant risk as a result of this change, this j j' change will not result in a significant increase in the consequences of an accident.

, 2. Create the possibility of a new or different kind of accident from any previously analyzed.

l Deletion of Table 4.8-1,in accordance with GL 94-01,is an administrative change

j. that will not impact plant the plant design or operation. Appropriate testing, in j, accordance with the Maintenance Rule, will continue. Therefore, this change does not create the possibility of a new or different kind of accident from any 1-previously analyzed.

i' The proposed change to extend the AOT for the EDGs does not alter the physical i i design, or configuration of the plant. The EDG operation remains unchanged,

therefore, this change does not create the possibility of a new or different kind of  ;

j accident from any previously analyzed. I i

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3. Involve a significant reduction in a margin of safety.

Deletion of Table 4.8-1,in accordance with GL 94-01, ensures that the requirements and provisions of 10 CFR 50.65 and the guidance of Regulatory

. Guide 1.160 are met. The program put in place by these documents will ensure that any degradation of the EDGs is identified and appropriate action is taken.

Therefore, this change does not involve a significant reduction in the margin of safety.

I A change to the maintenance schedule was performed to conform with vendor

, recommendations. This change in schedule required an increase in the duration of the 18 month and longer maintenance activities. Due to the number of shared systems, three of the four EDGs are required to meet all of the safety functions  ;

for each unit. However, the TSs conservatively assume four EDGs are necessary i f for unit operation; therefore, loss of any one EDG causes entry into a LCO action

, statement on both units. Performing the required maintenance with a 72-hour AOT will result in more EDG unavailability per year than would be required if the AOT was 7 days. Therefore, the 7-day AOT would not result in a significant l reduction in the margin of safety.

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• ENCLOSURE 4 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SON-TS-96-08)

REVISED TS PAGES

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.4 l 3/4.8 ELECTRICAL POWER SYSTEMS

. . i 3/4.8.1 A.C. SOURCES '

OPERATING LIMITING CONDITION FOR OPERATION 3.8.1.1 As a minimum, the following A.C. electrical power sources shall be OPERABLE:

l l a. Two physically independent circuits between the offsite transmission network and the onsite Class 1E distribution system, and

b. Four separate and independent diesel generator sets each with:

1. Two diesels driving a common generator I

2. Two engine-mounted fuel tanks containing a minimum volume of 250 gallons of. fuel, per tank

3. A separate fuel storage system containing a minimum volume of 62,000 gallons of fuel,

4. A separate fuel transfer pump, and

5. A separate 125-volt D.C. distribution panel, 125-volt D.C.

l battery bank and associated charger.

l APPLICABILITY: MODES 1, 2, 3 and 4.

ACTION: i i

a. With one offsite A.C. circuit of the above required A.C. electrical R209 i power source inoperable, demonstrate the OPERABILITY of the remaining  ;

offsite A.C. circuit by performing Surveillance Requirement 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter.

Restore at least two offsite circuits to OPERABLE status within i 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in  !

COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. l b.#@ With diesel generator set (s) 1A-A and/or 2A-A or 1B-B and/or 2B-B of l the above required A.C. electrical power sources inoperable, l demonstrate the OPERABILITY of the remaining A.C. sources by ]

performing Surveillance Requirement 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and determining OPERABLE diesel R209 generator sets are not inoperable due to comon cause failure or performing Surveillance Requirement 4.8.1.1.2.a.4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; L- restore at least four diesel generator sets to OPERABLE status within ,

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

• or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and R141 in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

• The.72-hour action statement may be extended for an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for one train of diesel generators (either 1A-A and 2A-A, or IB-B and 2B-B) during the performance of Surveillance Requirement 4.8.1.1.2.f.1. A temporary fuel supply R141

must be connected to the diesel generator set that is having the associated fuel tanks cleaned.

1. Required actions, to verify OPERABLE diesel. generator sets are not inoperable

! due to common cause failure or perform SR 4.8.1.1.2.a.4, shall be completed if R209 this action is entered.

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@ The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement may be extended to 7 days once per 18 months for planned diesel generator maintenance.

j- SEQUOYAH - UNIT 1 3/4 8-1 Amendment No. 100, 132, 137, 205,

l' ELECTRICAL POWER SYSTEMS

. j SURVEILLANCE REQUIREMENTS (Continued) l l

4.8.1.1.2 Each diesel generator set shall be demonstrated OPERABLE: )

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a. At least once per 31 days on a staggered test basis by: l

1. Verifying the fuel level in the engine-mounted day tanks.

2. Verifying the fuel level in the 7 day tank.

3. Verifying the fuel transfer pump can be started and transfers fuel from the storage system to the engine mounted fuel tanks.

4.

• Verifying the diesel starts from ambient condition and achieves in less than or equal to 10 seconds generator voltage and R199 frequency of 6900 1 690 volts and 60 1 1.2. The diesel generator shall be started for this test by using one of the j following signals with startup on each signal verified at least once per 124 days: lRS6 a) Manual, b) Simulated loss of offsite power by itself.

R56 c) An ESF actuation test signal by itself.

5.

• Verifying the generator is synchronized, loaded between 3960 kw R177 1 and 4400 kw in less than or equal to 60 seconds, and oparates I for greater than or equal to 60 minutes, and

6. Verifying the diesel generator is aligned to provide standby power to the associated shutdown boards.

b. At least once per 31 days and after each operation of the diesel where the period of operation was greater than or equal to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> by checking for and removing accumulated water from the engine-mounted fuel tanks. l

c. At least once per 92 days and from new fuel oil prior to addition to  !

the 7-day tanks by verifying that a sample obtained in accordance with ASTM-D270-1975 has a water and sediment content of less than or equal to .05 volume percent and a kinematic viscosity @ 100*F of greater than or equal to 1.8 but less than or equal to 5.8 centi-stokes when tested in accordance with ASTM-D975-77, and an impurity level of less than 2 mg. of insolubles per 100 ml. when tested in accordance with ASTM-D2274-70.

• The diesel generator start (10 sec) and load (60 sec) from standby conditions shall be performed at least once per 184 days in these surveillance tests. All other diesel generator engine starts and loading for the purpose of this R56 surveillance testing may be preceded by an engine idle start, followed by gradual acceleration to synchronous speed (approximately 900 rpm),

synchronization, and gradual loading. lR199 SEQUOYAH - UNIT 1 3/4 8-3 Amendment Nos. 52, 64, 99, 109, 137, 173, 195,

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J SEQUOYAH - UNIT 1 3/4 8-7 Amendment No. 52,

e ATTACHMENT TO TABLE 4.8-1 DIESEL GENERATOR REQUALIFICATION PROGRAM THIS PAGE INTENTIONALLY DELETED i

l i SEQUOYAH - UNIT 1 3/4 8-7b Amendment No. 52,

3/4.0 ELECTRICAL POWER SYSTEMS BASES 3/4.8.1 and 3/4.8.2 A.C. SOURCES AND ONSITE POWER DISTRIBUTION SYSTEMS The OPERABILITY of the A.C. and D.C power sources and associated distri-bution systems during operation ensures that sufficient power will be available to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of accident conditions within the facility. The minimum specified independent and redundant A.C. and D.C. power ,

sources and distribution systems satisfy the requirements of General Design i Criteria 17 of Appendix "A" to 10 CFR 50.

The ACTION requirements specified for the levels of degradation of the power sources provide restriction upon continued facility operation commen-surate with the level of degradation. The OPERABILITY of the power sources are l consistent with the initial condition assumptions of the accident analyses and are based upon maintaining at least one redundant set of onsite A.C. and D.C.

power sources and associated distribution systems OPERABLE during accident  !

conditions coincident with an assumed loss of offsite power and single failure l of the other onsite A.C. pource. Extension of the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed LCO time to l seven days is a recognition of maintenance time requirements. 1 The footnote for Action b of LCO 3.8.1.1 requires completion of a R209 determination that the OPERABLE diesel generators are not inoperable due to common cause failure or performance of Survei] lance 4.8.1.1.2.a.4 if Action b is entered. The intent is that all diesel generator inoperabilities must be investigated for common cause failures regardless of how long the diesel generator inoperability persists.

The action to determine that the OPERABLE diesel generators are not inoperable due to common cause failure provides an allowance to avoid unnecessary testing of OPERABLE diesel generators. If it can be determined that the cause of the inoperable diesel generator does not exist on the OPERABLE diesel generators, Surveillance Requirement 4.8.1.1.2.a.4 does not have to be performed. If the cause of inoperability exists on other diesel generator (s), and the other diesel generator (s) would be declared inoperable upon discovery and Action e of LCO 3.8.1.1 would be entered as applicable.

Once the common failure is repaired, the common cause no longer exists, and the action to determine inoperability due to common cause failure is satisfied. If the cause of the initial inoperable diesel generator cannot be conformed not to exist on the remaining diesel generators, performance of Surveillance 4.8.1.1.2.a.4 suffices to provide assurance to continued OPERABILITY of the other diesel generators.

According to Generic Letter 84-15, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that the OPERABLE diesel generators are not affected by the same problem as the inoperable diesel generator.

Additional ACTION requirements are specified for performance of the chemical cleaning required by Surveillance Requirement 4.8.1.1.2.f.1. The motor-driven fuel pumps for the diesel generator set with the tanks being cleaned will be temporarily connected to the underground storage tanks for the R141 other diesel generator set with the same train designation. An additional fuel-oil inventory of approximately 68,000 gallons will be available in one of SEQUOYAH - UNIT 1 B 3/4 8-1 Amendment No. 12, 137, 173, 205,

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3/4,8 ELECTRICAL POWER SYSTEMS

-3/4.8.1 A.C. SOURCES  ;

OPERATING LIMITING CONDITION FOR OPERATION

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3.8.1.1 As a minimum, the following A.C. electrical power sources shall be l OPERABLE:

a. Two physically independent circuits between the offsite  ;

transmission network and the onsite Class 1E distribution system, [

and -

b. Four separate and independent diesel generator sets each with: ,

1. Two diesels driving a common generator

! 2. Two engine-mounted fuel tanks containing a minimum volume.of 250 gallons of fuel, per tank

3. A separate fuel storage system containing a minimum volume of 62,000 gallons of fuel, ,

4. A separate fuel transfer pump, and

5. A separate 125-volt D.C. distribution panel, 125-volt D.C.

l battery bank and associated charger.

APPLICABILITY: MODES 1, 2, 3 and 4.

ACTION:

a. With one offsite A.C. circuit of the above required A.C. electrical power sources inoperable, demonstrate the OPERABILITY of the R195 remaining offsite A.C. circuit by performing Surveillance ,

j Requirement 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. Restore at least two offsite circuits to l l OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY _ '

! within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

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b.#@ With diesel generator set (s) 1A-A and/or 2A-A or 1B-B and/or 2B-B of the above required A.C. electrical power sources inoperable, lR195 demonstrate the OPERABILITY of the remaining A.C. sources by performing Surveillance Requirement 4.8.1.1.1.a within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and determining OPERABLE R195 diesel generator sets are not inoperable due to common cause i failure or performing Surveillance Requirement 4.8.1.1.2.a.4 within j l 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; restore at least four diesel generator sets to OPERABLE  ;

status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

• or be'in at least HOT STANDBY within the I next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. R123 )

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• The 72-hour action statement may be extended for an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for one train of diesel generators (either 1A-A and 2A-A, or 1B-B and 2B-B) during the performance of Surveillance Requirement 4.8.1.1.2.f.1. A temporary fuel supply must be connected to the diesel generator set that is having the associated 1 fuel tanks cleaned.

1. Required actions, to verify OPERABLE diesel generator sets are not inoperable R195 due to common cause failure or perform SR 4.8.1.1.2.a.4, shall be completed if this action is entered.

i @ The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement may be extended to 7 days once per 18 months for planned diesel generator maintenance. 1

( SEQUOYAH - UNIT 2 3/4 8-1 Amendment No. 89, 119, 123, 195, j i i l i l

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ELECTRICAL POWER SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) 4.8.1.1.2 Each diesel generator set shall be demonstrated OPERABLE:

a. At least once per 31 days on a staggered test basis by: l

1. Verifying the fuel level in the engine-mounted day tanks.

2. Verifying the fuel level in the 7 day tank.

3. Verifying the fuel transfer pump starts and transfers fuel from the storage system to the engine mounted fuel tanks.

4.

• Verifying the diesel starts from ambient condition and achieves in less than or equal to 10 seconds generator voltage and frequency shall be 6900 i 690 volts and R186 60 i 1.2 Hz. The diesel generator shall be started for this test by using one of the following signals with startup on each signal verified at least once per 124 days: R99 a) Manual.

b) Simulated loss of offsite power by itself.

c) An ESF actuation test signal by itself. R44

5.

• Verifying the generator is synchronized, loaded between 3960 kw and 4400 kw ir less than or equal to 60 seconds, and operates for greater than or equal to 60 minutes, and R164 i

6. Verifying the diesel generator is aligned to provide standby power to the associated shutdown boards.

b. At least once per 31 days and after each operation of the diesel where the period of operation was greater than or equal to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> by checking for and removing accumulated water from the engine- ,

mounted fuel tanks. I

c. At least once per 92 days and from new fuel oil prior to addition to the 7-day tanks by verifying that a sample obtained in j accordance with ASTM-D270-1975 has a water and sediment content of )

less than or equal to .05 volume percent and a kinematic viscosity l

@ 100*F of greater than or equal to 1.8 but less than or equal to l 5.8 centi-stokes when tested in accordance with ASTM-D975-77, and j an impurity level of less than 2 mg. of insolubles per 100 ml. when  !

tested in accordance with ASTM-D2274-70. j l

• The diesel generator start (10'sec) and load (60 sec) from standby conditions shall be performed at least once per 184 days in these surveillance tests. All R44 other diesel generator engine starts and loading for the purpose of this surveillance testing may be preceded by an engine idle start, followed by )

< gradual acceleration to synchronous speed (approximately 900 rpm),  !

synchronization, and gradual loading. lR186 SEQUOYAH - UNIT 2 3/4 8-3 Amendment Nos. 44, 56, 88, 99, 123, 164, 186, s

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I TABLE 4.8-1 DIESEL GENERATOR RELIABILITY l

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THIS PAGE INTENTIONALLY DELETED l l

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l SEQUOYAH - UNIT 2 3/4 8-8 Amendment No. 44,

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ATTACHMENT TO TABLE 4.8-1

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DIESEL GENERATOR REQUALIFICATION PROGRAM THIS PAGE INTENTIONALLY DELETED SEQUOYAH - UNIT 2 3/4 8-8b Amendment No. 44,

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3/4.8 ELECTRICAL POWER SYSTEMS BASES 3/4.8.1 AND 3/4.8.2 A.C. SOURCES AND ONSITE POWER DISTRIBUTION SYSTEMS The OPERABILITY of the A.C. and D.C power sources and associated distribution systems during operation ensures that sufficient power will be available to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of accident condi-tions within the facility. The minimum specified independent and redundant A.C. and D.C. power sources and distribution systems satisfy the requirements of General Design Criterion 17 of Appendix "A" to 10 CFR 50.

The ACTION requirements specified for the levels of degradation of the power sources provide restriction upon continued facility operation commensurate with the level of degradation. The OPERABILITY of the power sources are consistent with the initial condition assumptions of the safety analyses and are based upon maintaining at least one redundant set of onsite A.C. and D.C. power sources and associated distribution systems OPERABLE during accident conditions coincident with an assumed loss of offsite power and single failure of the other onsite A.C. source. Extension of the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed LCO i time to seven days is a recognition of maintenance time requirements.

The footnote for Action b of LCO 3.8.1.1 requires completion of a l determination that the OPERABLE diesel generators are not inoperable due to '

common cause failure or performance of Surveillance 4.8.1.1.2.a.4 if Action b is entered. The intent is that all diesel generator inoperabilities must be investigated for common cause failures regardless of how long the diesel R195 generator inoperability persists.

1 l l The action to determine that the OPERABLE diesel generators are not inoperable due to common cause failures provides an allowance to avoid unnecessary testing of OPERABLE diesel generators. If it can be determined that the cause of the inoperable diesel generator does not exist on the  ;

OPERABLE diesel generators, Surveillance Requirement 4.8.1.1.2.a.4 does not I have to be performed. If the cause of inoperability exists on other diesel ,

generator (s), the other diesel generator (s) would be declared inoperable upon discovery and Action e of LCO 3.8.1.1 would be entered as applicable. Once the )

common failure is repaired, the common cause no longer exists, and the action to determine inoperability due to common cause failure is satisfied. If the cause of the initial inoperability diesel generator cannot be confirmed not to exist on the remaining diesel generators, performance of Surveillance 4.8.1.1.2.a.4 suffices to provide assurance of continued OPERABILITY of the other diesel generators.

According to Generic Letter 84-15, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that the OPERABLE diesel generators are not affected by the same problem as the inoperable diesel generator.

Additional ACTION requirements are specified for performance of the R123 chemical cleaning required by Surveillance Requirement 4.8.1.1.2.f.1. The motor-driven fuel pumps for the diesel generator set with the tanks being cleaned will be temporarily connected to the underground storage tanks for the other diesel generator set with the same train designation. An additional fuel-oil inventory of approximately 68,000 gallons will be available in one of the yard storage tanks prior to the start of the chemical cleaning of any SEQUOYAH - UNIT 2 B 3/4 8-1 Amendment No. 123, 164, 195,