ML20202C613

Safety Evaluation Supporting Amend 219 to License NPF-3

ML20202C613
Person / Time
Site:	Davis Besse
Issue date:	02/03/1998
From:	NRC (Affiliation Not Assigned)
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ML20202C606	List: ML20202C601 ML20202C613 ML20202C620
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NUDOCS 9802120294
Download: ML20202C613 (15)

Text

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NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 9004640M SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION 8{ LATED TO AMENDMENT NO. 219 TO FACILITY OPERATING-LICENSE NO. NPF-3 TOLEDO EDISON COMPANY (INTERIOR SERVICE COMPANY AtiD THE CLEVELAND ELECTRIC ILLUMINATING COMPANY DAVIS-BESSE NUCLEAR POWER STATION. UNIT 1 DOCKET NO. 50-346

1.0 INTRODUCTION

By letter dated October 28, 1996, as supplemented by letters dated August 19 and October 16, 1997 Toledo Edison Company (TE), Centerior Service Company, and The Cleveland Electric 111uminating Company (the licensees), submitted a request for changes to the Davis-Besse Nuc',sar Power Station (DBNPS), Unit 1, Technical Specifications (TSs).

The supplemehtal information did not impact the proposed no significant hazards considerr. tion determination.

The requested amendment would revise TS Section 3/4.8.1, "A.C. Sources," TS Section 3/4.8.2, "Onsite Power Distribution Systems," TS Table 4.8.1, " Battery Surveillance Requirements," and the associated bases.

Surveillance l

requirements would be modified to account for the increase in the fuel cycle from 18 to 24 months. Administrative changes would also be made.

l On August 19, 1997. TE responded to a request for additional information (RAl) dated June 25, 1997.

During subsequent telephone conversations with TE on j

September 29, October 1, October 8, October 15, and December 29, 1997, the l

1ssues identified in the RAI were further explained, new issues were identified and additional information regarding DBNPS surveillance test programs was obtained. As mentioned in the first four discussionr. and summarized in a TE letter dated October 16, 1997 TE will submit a license amendment application by the end of 1998 to propose additional TS changes to l

address the issues identified by the staff. This should allow ample time for the staff to review and approve the request prior to the next scheduled battery performance testing in the spring of 2000.

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2.0 RACKGROUND j

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Improved reactor fuels allow licensees to consider an increase in the duration of the fuel cycle for their facilities.

The staff has reviewed requests for individual plants to modify surveillance intervals to be compatible with a 24-month fuel cycle. The NRC issued Generic Letter (GL) 91-04, " Changes in T

l Technical Specification Surveillance Intervals to Accommodate a 24-Month Fuel Cycle," on April 2, 1991, to provide generic guidance to licensees for preparing such license amendment requests.

TSs that specify an 18-month surveillance interval could be changed to state that these surveillances are to be performed once per refueling interval. The

-notation for surveillance intervals would then be changed to include the definition of a " Refueling Interval" with the existing "R" notation for surveillances that are generally performed during a refueling outage. The frequency for the interval indicated by this notation would also be changed i

from 18 months to "at least once every 24 months." The provision to extend l

surveillances by 25 percent of the specified interval would extend the time j

limit for completing these surveillances from the existing limit of 22.5 i

months to a maximum of 30 months.

Licensees must address instrument drift when proposing an increase in the surveillance interval for calibrating instruments that perform safety functions to include providing the capability for safe-shutdown. The effect l

of the increased calibration interval on instrument errors must be addressed i

because instrument errors caused by drih. were considered when determining

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safety system setpoints and when performing safety analyses.

- For other 18-month surveillances, licensees should evaluate the effect on-safety of the change in surveillance intervals to accommodate a 24-month fuel cycle. This evaluation should support a conclusion that the effect on safety-l 1s small.

In addition, licensees should confirm that historical maintenance and surveillance data do not invalidate this conclusion.

Licensees should I

confirm that the performance of surveillances at the bounding surveillance interval limit provided to accommodate a 24-month fuel cycle would not L

invalidate any assumption-in the riant-licensing basis.

In consideration of-1

- these confirmations,- the licensees need not quantify the effect of the change

'in surveillance intervals on the availability of individual systems or components.

3.0 EVALUATION This license amendment request will extend several surveillance testing intervalsfromevery18monthstoeachrefuelinginterval. The licensees

,i with "at least once each i

proposed replacing "at least once per 18 months REFUELING INTERVAL," for the TSs described below.

" Refueling Interval" is 4

currently defined in the D8NPS TSs as "a period of time s 730 days" for a 24-month fuel cycle.

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3 Consistent with the guidance in GL 91-04, the licensees also proposed to remove the restriction "during shutdown" from several of the TSs. This GL guidance is not consistent with the current NRC Office of Nuclear Reactor Regulation (NRR),-Electrical Engineerine Branch, technical position for several electrical power system TSs. This technical position is reflected in NUREG-1430. " Standard Technical Specifications - Babcock and Wilcox Plants,"

dated April-1995.

Therefore, where noted below, the licensees' requests to remove the restriction "durity shutdown" have been denied. As noted in the TE supplemental submittals, and ay telephone conversation between TE and NRR staff on December 29, 1997 the licensees confimed that these denials would have-nosafetyimpactonplantoperations.

The proposed changes allow the continued application of TS 4.0.2.

This TS allows surveillance intervals to be increased up to 25 percent on a nonroutine basis (30 months) in accordance with the GL, A paragraph was added (Amendment 213, dated February 10,1997) to TS Bases 4.0.2, consistent with GL 91-04, which ensures that surveillances are performed in an operational moda consistent with safe plant operation. This-TS bases section already included clarification that the allowable tolerance not be used as a convenience to

. repeatedly schedule the performance of surveillances at the allowable tolerance limit.

The licensees performed the safety assessment for the proposed changes to the surveillance test intervals in accordance with the GL 91-04 requirements stated above. This assessment entailed reviewing the historical maintenance and surveillance test data at the bounding surveil 16nce interval limit, performing an evaluation to ensure that a 24-month surveillance test interval would not invalidate any assumption in the plant licensing bases, and the determination that the effect on safety is small. Only the period since 1985 was reviewed. This is most representative of current operating conditions since many changes occurred after the loss of feedwater event in 1985. This period includes five refueling outages and four operating cycles of test results.

3.1 Surveillance Reauirement 4.8.1.1.1.b (nartial denial)

The existing 15 surveillance requirement (SR) 4.8.1.1.1.b requires that at least once per 18 months, during shutdown, each qualified circuit between the offsite transmission network and'the onsite Class lE A.C. electrical power distribution system be demonstrated operable by transferring (manually and automatically) the unit power supply to each of the offsite c9rcuits.

The propbsed change in SR 4.8.1.1.1.b replaces the words "at least once' per 18 months, during shutdown".with "at least once each REFUELING INTERVAL." As discussed in Section 3.0, the removal of the restriction "during shutdown" is denied.

TE reviewed the licensing basis, applicable surveillance data and maintenance records. The licensees determined that during the period since 1985, which includes five refueling outages and four ope *ating cycles, no failures

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occurred during surveillance testing. The licensees also reviewed maintenance l

records related to this SR. No problems were identified that resulted in 4

equipment being inoperable.

t The licensees concluded that, based on the results of the maintenance and

_ surveillance review, the change to a 24-month fuel cycle was acceptable.

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addition, the. licensees concluded that the licensing basis would not be 1

invalidated by increasing the surveillance interval, and that the impartz on safety would be small.

Further, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2= on a nonroutine basis.

The staff reviewed the proposed changes and the licensing basis and determined that all actions specified in the GL were completed. The effect on safety'

- would be small, historical data do not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated.

Therefore, this change (except the partial denial as fiescribed above) is acceptable.

3.2 1R 4.8.1.1.2.d (nartial denial)

L SR 4.8.1.1.2.d requires that each emergency diesel generator (EDG) be demonstrated operable at least once per 18 months during shutdown by:

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(1)

Verifying the EDG capability to reject a load equal to the largest single emergency load without tripping; (2)

Simulating a loss of offsite power in conjunction with a safety features actuation system (SFAS) test signal:

4 (a)

Verifying de-energization of the essential busses and load shedding from the essential _ busses; (b) Verifying the EDG starts from ambient condition on the auto-start signal, energizes the essential busses with permanently 4

connected loads, energizes the auto-connected essential loads through the load sequencer and operates for 2 5 minutes:while 4

the generator it loaded with essential: loads; and (c) Verifying that all EDG trips, except engine overspeed and generator differential, are automatically bypassed upon loss of voltage on the essential bus and/or an SFAS test signal; (3) _ Verifying that the EDG operates for h 60 f.tutes while loaded to 2 2,000 kw;_and 4

(4) Verifying that the auto-connected loads to each EDG do not exceed the-2,000 hour0 days <br />0 hours <br />0 weeks <br />0 months <br /> rating of 2,838 kw.

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' It is proposed that in SR 4.8.1.1.2.d. the words "at least once per 18 months, during shutdown" be replaced with "at least once each REFUELING INTERVAL." As discussed in Section 3.0, the removal of the restriction "during shutdown" is denied.

TE reviewed the licensing basis, appitcable surveillance data, and maintenance records. The licensees determined that during the period since 1985 which includes five refueling outages and four operating cycles, three failures occurred during surveillance testing. Two sequencer relays failed and one EDG failed to reach rated voltage during a monthly test due to a degraded field flash contactor.

Preventive maintenance and regular replacement activity was initiated to minimize further failures of the relays.

The contactor was replaced and a timing program was initiated to ensure proper function, though an extended fuel cycle would not impact failure identification, as this is subject to monthly testing.

The licensees reviewed maintenance records related to this SR. No abnormal component degradations or other anomalies were identified that would impact a change to a 24-month fuel cycle.

The licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.

In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, and that the impact on safety would be small.

Further, the licensees determined that it would be acceptable to continue with the aoplication of TS 4.0.2 on a nonroutine basis.

The staff reviewed the proposed changes and the licensing basis and determined i

that all actions specified in the GL were completed.

The effect on safety would be small, historical data (with the corrective actions factored in) do not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated.

Therefore, this change (except the partial denial as described above) is acceptable.

3.3 SR 4.8.2.3.2.c faccepted) and SR 4.8.2.3.2.d (partial denial) l SR 4.8.2.3.2.c requires that at least once per 18 months each 125-volt battery l

and charger shall be demonstrated operable by verifying:

l (1) The cells, cell plates, and battery racks show no visual indication l

of physical damage or abnormal deterioration; (t) The cell-to-cell and terminal connections are clean, tight, and coated with anti-corrosion material; (3) The resistance of each cel,1-to-cell and terminal connection is less than or equal to 150 X 10' ohms; and (4) The battery charger will supply at least 475 amperes at a minimum of 130 volts for at least A hours, w

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6-The battery charger testing required in the current SR 4.8.2.3.2.c.4 is normally >erformed with the plant online (each train has a standby battery charger witch is used during the online testing) and will continue to be perfarmed on an Il-ronth frequency.

To reflect the intent to continue to perform current SP 4.0.2.3.2.c.4 on an 18-month interval, but to perform current SRs 4.8.2.3.2.c.1,into SR 4.8.2.3.2.c, rewording SR 4.8.2.3.3.c as2,.and 3 each relocate SR 4.8.2.3.0c.4 1 1105r 0

1. c. 'At-ietst nnee'psr 18 months bi~verifyina that the battery chargers will supply at inst 475 amperes at a mWimum of 130 volts for at least 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />st and at least once each REFUELING INTERVAL by verifying thatt" SR 4.8.2.3.2.d requires that at least once per 18 months, during shutdown, each 125-volt _ battery and charger be verified operable by verifying that the bntery capacity is adequate to supply and maintain in operable status.all of the actual or simulated emergensy loads for the design duty cycle when the battery is subSried to a battery service test.

TE proposes that in SR 4.8.2.3.2.d. the words "At least once per 18 months, during shutdown" be replaced with "At least once each REFUELING INTE* VAL." As discussed in Section 3.0, the removal of the restriction "during shutdown" is denied.

TE reviewed the licensing basis, applicable surveillance data, and maintenance records. The licensees determined that during the period from January 1990 (after battery replacement was completed) through October -1994, no failures occurred during surveillance testing. The licensees revtewed maintenance records related to these SRs over the same time period,.

No problems were

-Identified that resulted in equipment being inoper:ble.

The licensees concluded that, based on the results of the maintenance and-surveillance review, the change to a 24-month fuel cycle was acceptable, in addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, and-that the impact on safety would be small.

Further, the licensees determined that it would be -

acceptable to continue with the application of TS 4.0.2 on a nonroutine basis.

The staff reviewed the proposed changes and the licensing basis and determined

-that all actions =specified in the GL were completed.

The effect on safety would be small, historical data do not contradict this conclusion, and no assumptiors in the plant licensing basis would be invalidated. Therefore, this change (except the partial denial as described above) is acceptable.

3.4 SR 4.8.2.3.2.e, (denial)

SR 4.8.2.3.2.e requires that at least once per 60 months, during shutdown.

each 125-volt battery and charger be verified operable by verifying that the battery capacity is at least 80 percent of the manufacturer's rating when

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subjected to a performrnce discharge test. Once per 60-month interval, this performance discharge test may be performed in lieu of the battery service test.

TE proposes that in SR 4.8.2.3.2.e. the words "during shutdown" be deleted.

As stated in Section 3.0 above, the removal of the words "during shutdown" is 4,.

not acceptable. Therefore, this proposed change is denied.

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During the review of this proposed change,' the staff identified an issue

-outside the scope of the current license amendment request.

In an RAI dated June 25, 1997, the staff requested the following information regarding SR 4.8.2.3.2.e:

(a) Please explain how the battery discharge test will be performed once per 60 months while the unit is operating without going beyond the limits of the LCO (which requires restoration of the battery to operable status within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />); and (b) This SR states:

Once per 60-month interval, this performance discharge test may be performed in lieu of the battery service test.

Does the performance discharge test envelop the battery service test?

In their response of August 19, 1997 TE stated:

Although the proposed revision to SR 4.8.2.3.2.e removes the restriction to conduct performance discharge testing "during shutdown," the DBNPS does not plan to perform battery discharge testing while the plant is operating.

Under a 24-month fuel cycle, performance discharge testing is planned to be performed during every other refueling outage, or approximately every 4 years. The purpose of the proposed revision is to bring the SR into conformance with NRC Generic Letter (GL) 91-04, " Changes in Technical Specification Surveillance Intervals to Accommodate a 24-Month fuel Cycle,"' dated April 2,1991, wherein the NRC staff concluded that the TS need not restrict surveillances as only being performed during shutdown, and that licensees are to give proper regard for performing refueling interval surveillances during power operation or during another mode that is consistent with the safe conduct of the surveillance.

With the second part of the question, the performance test load profile

- does not completely envelop the service test load profile, in particular during the first minute of the service test load profile.

However, the total ampere-hours dischaaed during the performance test exceeds the total ampere-hours discharged during the service test.

In other words, the performance test is more challenging in terms of battery capacity, but the service test is more challenging in terms of voltage drop during the first minute high current demand.

. As stated in TS Bases 3/4.8, the Surveillance Requirements for demonstrating OPERABILITY of the station batteries are based on the recommendation of Regulatory Guide 1.129, " Maintenance Testing and Re)lacement of Large Lead Storage Batteries for Nuclear Power Plants,"

Fearuary 1978, and IEEE Std. 450-1980, "lEEE Recommended Practice for Maintenance, Testing, and Replacement of Large Lead Storage Batteries for Generating Stations and Substations." The DBNPS is aware that the more recent lEIE Std. 450-1995 discusses a " modified" performance test that would envelop the lead profile of the service test.

This " modified" performance test is a worst case load profile of the traditional service test and performance test combined.

However, the purpose of LAR 95-0021 (this amendment request) is to propose changes pertinut to the increased operating cycle duration, consistent with the NRC's geidance in GL 91-04.

Adoption of more current testing techniques is outside the scope of the proposed License Amendment Request and beyond the current Licensing Basis.

However, the DBNPS may consider the adoption of a later version of IEEE Std. 450 during the course of the conversion of the current DBNPS Technical Specification to the improved

" Standard Technical Specification for Babcock and Wilcox Plants," as con-tained within NUREG-1430 (ISTS). Asstatedinit's(sici November 26, 1996, letter to NRC (TE Serial Number 2418), the DBNPS present'y plans to submit a License Amendment Request relative to conversion to the ISTS in 1999.

During subsequent telephone conversations regarding the first issue, the staff enquired why DBNPS is proposing to remove the restriction to conduct performance discharge testing *during shutdown," when DBNPS does not plan to perform the battery discharge test while the plant is operating with a 24-month fuel cycle.

Battery discharge testing is planned to be performed during every other refueling outage, or approximately every 4 years.

Regarding the second part of the question, the staff indicated that not performing the modified performance discharge test described IEEE Std. 450-1995 and NUREG-1430 may create a safety problem.

TE responded in the October 16, 1997, letter:

Regarding the first part of the question TE believes that the proposed change, removing the phrase "during shutdown" from the SR, is consistent with the NRC's recommendation in GL 91-04.

However, should the NRC staff choose to not approve this portion of the License Amendment application, it would not impact the conversion of the DBNPS TS to a 24-month fuel cycle.

Regarding the second part of the question, TE notes that the last battery performance discharge tests were performed in the fall of 1994 during the Ninth Refueling Outage (9RFO) for station batteries "2P" and "2N," and in the spring of 1996 during 10RF0 for station batteries "lP" and "lN."

Hence, given the 60-month surveillance interval of SR 4.8.2.3.2.e, battery performance discharge testing is not due during the upcoming IIRF0, which is scheduled to commence in April 1998.

The results of the last

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• perfomance discharge tests for these batteries were as follows:

124.5%

capacity for station battery "lP,"-121.1% capacity for station battery

'1N " 118.9% capacity for station battery "2P," and 123.3% capacity for station battery "2N."

The oldest of these batteries was installed in September 1986.

Considering the above, TE proposes to submit a separate License Amendment application for a change to SR 4.8.2.3.2.e to reflect the modified performance discharge test described in IEEE Std. 450-1995 and NUREG-1430.

This License Amendment appitcation will be submitted by the end of 1998, which should allow ample time for NRC review and approval prior to the next scheduled performance of SR 4.8.2.3.2.e in the spring of 2000 (12RFO), for station batteries "2P" and "2N"....

The staff acknowledges that the licensees have committed to submit a separate license amendment application.

3.5 SR 4.a.2.3.2.f f eartial denial)

SR 4.8.2.3.2.f requires that each 125-volt battery and charger be verified operable every 18 months, during shutdown, through performance discharge tests of battery capacity given to any battery that shows signs of degradation or has reached 85 percent of the service life expected for the application.

Degradation is indicated when the battery capacity drops more than 10 percent of rated capacity from its average on previous performance tests, or is below 90 percent of the manufacturer':: rating.

TE proposes that in SR 4.8.'2.3.2.f. the words 'Every 18 months, during shutdown" be replaced with "Every REFUELING INTERVAL."

-.TE reviewed the licensing basis, applicable surveillance data, and maintenance records. The licensees determined that during the period from January 1990

. (after battery replacement was completed) through October 1994, no failures occurred during surveillance testing. The licensees reviewed maintenance records related to these SRs over the same time period. No problems were identified that resulted in equipment being inoperable.

The licensees concluded that,- based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.

In addition, the_ licensees concluded that the licensing basis would not be-invalidated by increasing the surveillance interval, and that the impact on safety would be small.

Hurther, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2 on a nonroutine basis,

_The staff reviewed.the proposed changes and the 1_icensing basis and detemined that all actions specified-in the GL were completed. The effect on safety would be small, historical data do not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated.- Therefore, this. change (except the partial denial as described above) is acceptable.

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' During the review of this proposed change, the staff identified an issue outside the M ope of the current license amendment request.

In an RAI dated June 25, 1997, the staff posed the following question regarding SR 4.8.2.3.2.ft This SR states:

Degradation is indicated when the batterv capacity drops more than 10%

of rated capacity from its average on ;,revious performance tests, or is below 90% of the manufacturer's rating.

Should this read "... previous perfor. nance test..." as per IEEE Std. 450, instead of "... average on previous performance tests..." as noted in your application?

Toledo Edison's Auaust 19. 1997. Resoonse:

The existing SR was added to the DBNPS TS via License Amendment No. 100, dated March 12, 1987, based on by (sic) model Technical S)ecifications for station batteries guidance provided by the NRC t Toledo Edison (TE Iog Number 756, dated July 16,1981), and is consir ant with IEEE Std. 450-1980. However, the more recent IF.EE Std. 450-1 45 bases the degradat in determination only on the most recent test, rather than the average ci previous tests.

As noted above, the purpose of LAR 95-0021 is to propose changes pertinent to the increased operating cycle duration, consistent with the NRC's guidance in Generic letter 91-04. Adoption of more current testing requirements is outside the scope of the proposed License Amendment Request and beyond the current Licensing Basis. However, the DBNPS may consider the adoption of a later version of IEEE Std. 450 during the course of the conversion of the current DBNPS Technical Specifications to the ISTS.

During subsequent telephone conferences, the staff questioned whether the average of previous tests, which is consistent with IEEE Std. 450-1980, provides the true capacity of the batteries because it fails to account for sudden degradation of the battery capacity. On the other hand, IEEE Std. 450-1995 bases degradation determination only on the most recent test, thereby accounting for a-sudden degradation.

Toledo Edison's October 16. 1997. Resoonse:

As previously noted, given the 60-month required surveillance interval for SR 4.8.2.3.2.e. only service testing and no battery performance discharge testing is scheduled during the upcoming 11RF0, which is scheduled to commence in April 1998. The oldest station batteries "lP" and "lN,"

which were installed in September 1986, will not reach 85% of their service life until 12RF0. They will then need to be performance tested under the current SR 4.8.2.3.2.f. if they are not replaced.

1

c 11 Toledo Edison proposes to include in the above-mentioned separate License Amendment application a proposed change to SR 4.8.2.3.2.f to reflect that the test criteria should be based on the most recent test rather than based on the average of previous testing.

This is consistent with IEEE Std. 450 1995 and NUREG-1430. As noted above, this License Amendment application will be submitted by the end of 1998. This should allow ample time for NRC review and approval prior to the next scheduled battery performance testing in the spring of 2000 (12Rf0).

In ro'.ponsa to the staff telephone inquiry of October 1,1997, TE stated in thr n tohm 16, 1997 response:

e A 9 whng iR 4 m o la,f:

19 piosent!y.tains:

5..ay i8 months luring shutdown, performance discharge tests of battery cap rity

• ball be given to any battery that slows sigr.s of 1mya ht Mn r has.vached 85% of the service life expected for the ippliiat h.o Jegiadation is indicated when the battery capacity drops more than 10% of rated capacity from its average on previous no,rs,m3n u n.,,ls, in is below 90% of thn manufacturer's rating, the ou ohor /0, 1996 iiconse Amundment apalication proposes to change the en M n tro Inl vvil from "Every 10 montis" to "Every REFUELING m acu '. "is le th mider /ing pu. pose of this survelliance w e..

s p, nn.-nt M, case the frequency of conducting performance liv L r Lust, when ihn battery ha<. reached 05% of its service life or i

A o 4 r+hi ion e s ind kaN.L The proposed license Amendment would not 9o U.i s te..t renquency.

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' :s > td;.i h.u resicwnd this issue and concurs with the NRC staff's v % ion.

In 'ight 9f t he underlying purpose of this surveillance

,aqui. ment,.hi.out the NRL not approve this portion of the License Amrodinant, it woulit nt,t loipact the conversion of the DBNPS TS to a r eth fuel cycle.

This is because the surveillance requirement for an od

. ivv.e4 tod rew a,. my 1, only ipplicable after the battery performance 4m.ed yo !e ' eco h. iR 4 8.2.3 2, f), or reached 85% of its service r

i ie lho ninest a siiua batterlos, "lP" and "lN," which wero installed 7

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1908 dll ut ca.wh 35% of their :,ervico life until 12RFO.

l$cy. cwill then i)ced to be performance tasted uncler the current SR 4.R.? t ? f. I f Ihny are not replaced, loteJu Edison will loclude proposed changes that would make the present SR 4.8.2.3.2.f consi:, tent with the increased test frequency as specified in IEEE Std. 450-1995 and NUREG-1430, in the scope of the above-mentioned separate License Amendment application.

The proposed SR 4.8.2.3.2.f would read:

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• Except as noted below, an annual performance discharge or modified performance discharge test of battery capacity shall be given to any battery that shows signs of degradation or has reached 85% of the-service life expected for the applicatio;1. Degradation is indicated when the battery capacity dro)s more than 10% from its capacity on the previous performance disc 1arge or modified performance discharge test, or is below 90% of the manufacturer's rating.

If the battery has reached 85% of service life, delivers a capacity of 100% or greater of the manufacturer's rated capacity, and has shown no signs of degradation, performance testing at 2-year intervals is acceptable until the battery shows signs of degradation.

The staff acknowledges that the licensees have committed to submit a separate license amendment application.

3.6 TS Table 4.8-1 The staff posed the following questions in us RAI of June 25, 1997:

Regarding Table 4.8-1, " Battery Surveillance Requirements":

(a)

Is the restriction ou " level" in n.tnote (a) necessary?; and (b)

Is the restriction "...following a service or performance discharge test..." in Footnote (c) necessary?

Toledo Edison's Auaust 19. 1997. Resoonse:

Technical Specification Table 4.8-1, including current Footnote (a), was added to the DBNPS TS via License Amendment No. 100, dated March 12, 1987, based on the model Technical Specifications for station batteries guidance provided by the NRC to Toledo Edison (TE Log Number 756, dated July 16, 1981).

Although the Footnote (a) correction of the specific gravity parameter for electrolyte level is not required in the more recent IEEE Std. 450-1995, the purpose of LAR 95-0021 is to propose changes pertinent to tho increased operating cycle duration, consistent with the NRC's guidance in Generic Letter 91-04. As indicated above, adoption of more current testing requirements is outside the scope of the__ proposed License Amendment Request and beyond the current Licensing Basis. However, the DBNPS may consider the adoption of a later version of IEEE Std. 450 during the course of the conversion of the current DBNPS Technical Specifications to the ISTS.

Footnote (c) to TS Table 4.8-1, " Battery Surveillance Requirements," was added via License Amendment No. 158, dated July 16, 1991, in response to F

the Toledo Edison license amendment application dated March 1,1991 (TE Serial Number 1898). This footnote adds exceptions to the specific gravity requirements. As stated in the portion of TS Bases 3/4.8, also added via license Amendment 158, the exceptions to the specific gravity requirements are taken to allow for the normal deviations experienced

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13 after a battery discharge and subsequent recharge associated with a service or performance discharge test, and the specific gravity deviations are recognized and discussed in IEEE Std. 450-1980.

As further desertbed in the March 1, 1991, license a:aendment application and in the NRC Safety Evaluation accompanying License Amendment No. 158, a float charging current of less than 2 amperes is an acceptable method to declare the battery operable after a discharge test; other battery parameters, i.e., specific gravity, take longer to stabilize and cannot provide an immediate and an accurate determination of state-of-charge, in addition, data has shown that battery charging current responds more quickly than specific Cravity readings to changes in the state-of-charge.

Therefore, using charging corrent to determine the state-of-charge of the battery following a discharge test reduces the amount of time required to declare a battery operable.

The March 1, 1991, license amendment application was requested to allow for a potential reduction of critical path duration during a refueling outage.

The words "...following a service or performance discharge test..." are necessary since they preclude use of the float charging current measurement in lieu of specific gravity measurement for the 7-day (SR 4.8.2.3.2.a.1) and 92-day (SR 4.8.2.3.2.b.1) surveillance tests, when the spectile gravity would reasonably he expected to be stable and capable of providing an imediate and accurate determination of state-of-charge.

Toledo Edisoa October 16. 1997. Resoonig:

Based on discussions with the NRC staff, although the NRC does not believe that the noted restrictions in footnotes (a) and (c) of TS Table 4.8-1 are necessary, the NRC does not require that TE revise these footnotes.

Toledo Edison plans to reevaluate this issue during preparation of the above-mentioned separate License Amendment ap)11 cation, and may include additional proposed changes in the scope of t1at application, if warranted.

Based on above, the staff finds the TE response acceptable.

3.7 Additional NRC RAI Reaggit

-The RAI stated:

Regarding LAR 95-0021, Enclosure 3, Page 3:

The second paragraph indicates that the sizing of the batteries includes approximately 20% overcapacity to compensate for loss due to aging of batteries over a 20-year period.

Please provide details on how this conclusion was reached.

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• o 14 Toledo Edison Aucast 19. 1997. Resoonse:

Section 8.3.2.1.2 of the DBNPS Updated Safety Analysis Report (USAR describesthestationbatteriesandcitesthereferencedstatement) regarding sizing of the batteries. USAR Section 8.3.2.1.2 also includes a taken from D8NPS Calculation C-EE-detailed load list for each battery, hat the battery is adequately sized to 002.01-010.- The calculation shows t accommodate anticipated aging degradation to 80% of rated capacity, while still being capable of performing its safety function.

The calculation utilizes an aging factor of 1.32 for cell sizing, which includes the 1.25 aging factor recommended in IEEE Std. 485-1983, " Recommended Practice for Sizing Large Lead Storage Batteries for Generating Stations and Substations," plus additional conservatism to compensate for a battery charged to only g5% of capacity.(1.25 x 100%/g5% = 1.32).

The "20-year period" refers to the design life of the current station batteries. However,-the manufacturer-provided qualified service life of the current station batteries is actually a more conservative 16 years.

Since a capacity test result of less then 80% (reference TS SR 4.8.2.3.2.e) is actually what indicates end of battery life, the reference to "20-year" life for aging consideration does not have any correlation,to a Technical Specification requirement.

Technical Specification SR 4.8.2.3.2.f requires that performance discharge tests of battery capacity be given to 6ny battery that shows signs of degradation or has reached 85% of the service life expected for the application.

Since 16 years is the service life expected, this SR is required to be performed at 85% of 16 years,- or 13.6 years from installation.

. Toledo Edison October 16. 1997. Response:

The station batteries were initially sized to meet the original-plant-loads. Although " design margin" is not explicitly included in the current battery sizing calculation, the plant modification process, which is conducted in accordance with DBNPS procedure NG-EN-00301, " Plant-Modifications," ensures that any )1ent-modification affecting battery capacity is evaluated to ensure t1at all DC design parameters are properly addressed. -Further, a battery aging correction factor of 1.32 is used to accommodate a battery aged to 80% capacity and charged to 95% capacity.

<This value corresponds to the operability criterion defined in the TS, which establishes that the battery is dtclared inoperable once it falls below 80% of rated capacity.

The staff finds the TE response acceptable.

-3.8 TS Bases 3/4.8. " ELECTRICAL POWER SYSTEMS" These bases have been modified to account for the performance of certain tests et least once each refueling interval. -Since the modification is consistent with the TS changes evaluated above, the staff finds it acceptable.

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4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Ohio State official was notified of the proposed issu?nce of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

This amendment changes a requirement with respect to installation or use of a facility com)onent located within the restricted area as defined in 10 CFR Part 20 or c1anges a surveillance requirement.

The staff has determined that the amendment involves no significant incraase in the amounts, and no significant change in the types, of any effluent that may be released offsite, ased that there is no significant increase in individual or cumulative-occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding (62 FR 132). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuarce of the amendment.

6.0 CONCLUSION

The staff has concluded, based on the considerations discussed above, that:

(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner; (2) such activities will be conducted in compliance with the Commission.*

regulations; and (3) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor:

S.K. Mitra Date: February 3, 1998 i

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