ML20211E903

Application for Amends to Licenses NPF-68 & NPF-81,relaxing Slave Relay Test Frequency from Quarterly to Refueling Frequency

ML20211E903
Person / Time
Site:	Vogtle
Issue date:	08/24/1999
From:	Beasley J SOUTHERN NUCLEAR OPERATING CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20211E907	List: ML20211E903 ML20211E911
References
LCV-1359, NUDOCS 9908300169
Download: ML20211E903 (7)

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• J. Barnie Brastry,Jr., PE. - Southern Nuclear

,. . Vice Pesident Op: rating Company,Inc.

Vogtle Project 40 invemots Cenw Parkway PO Box 1295 Bemmgham, Alatama 35201 Tel 205932 7110 fax 205 9920403 SOUTHERN COMPANY Energy to Serve Your World*

LCV-1359 August 24, 1999 Docket Nos. 50-424 50-425 U. S. Nuclear Regulatory Commission

' ATTN: Document Control Desk Washington, D. C. 20555 Ladies and Gentlemen:

VOGTLE ELECTRIC GENERATING PLANT-REQUEST TO REVISE TECHNICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY SURVEILLANCE REQUIREMENT 3.3.2.5 In accordance with the provisions of 10 CFR 50.90, Southern Nuclear Operating Company (SNC) proposes to revise the Vogtle Electric Generating Plant (VEGP) Unit I and Unit 2 Technical Specifications (TS} 3.3.2 " Engineered Safety Feature Actuation System (ESFAS)

Instrumentation" to relax the slave relay test frequency from quarterly to a refueling frequency.

The associated Bases to Surveillance Requirement (SR) 3.3.2.5 clarifies that slave relay test frequency is adequate based on industry operating history, considering relay reliability and operating history data. The proposed change in slave relay test frequency is based on i information contained in Westinghouse Electric Corporation (Westinghouse) report WCAP-13878 (proprietary)" Reliability Assessment of Potter & Brumfield MDR Series Relays,"

l June 1994. By letter dated May 31,1996 from . Bruce A. Boger (NRC) to Tom Greene, )

I Westinghouse Owners Group (WOG), the NRC approved WCAP-13878, WCAP-14117, and WCAP-13900.

0)0 Enclosure 1 provides the basis for the proposed change. Pursuant to 10 CFR 50.92, Enclosure 2 demonstrates that the proposed change does not involve a significant hazard consideration. Enclosure 3 is a mark-up of the affected pages from the VEGP Unit I and Unit 2 TS and the affected Bases pages. Enclosure 4 contains the clean typed pages ,

reflecting the pro' posed changes. Enclosure 5 contains a copy of the WOG letters that 1 30N20 l 9908300169 990824 L PDR ADOCK 05000424 P PDR '

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transmitt'ed WCAP-13878, Revision 1 and WCAP-14117, Revision 1. As stated above, WCAP-13878, WCAP-14117 and WCAP-13900 were reviewed and approved by the NRC as part of a generic WOG program to relax the surveillance test frequency for slave relays.

Mr. J. B. Beasley, Jr. states that he is Vice President of Southern Nuclear Operating Company and is authorized to execute this oath on behalf of Southern Nuclear Operating Company and that, to the best of his knowledge and belief, the facts set forth in this letter are true.

SOUTHERN NUCLEAR OPERATING COMPANY By: /

l['JMBfslef,/f.

Sworn to andsubscribed before me this Yfday of ,1999.

0 My commissio expires: //l0 Notary Yublic / /

JBB/JPC Enclosure 1: Basis for Proposed Change Enclosure 2: Significant Hazards Evaluation Enclosure 3: Marked-Up TS and Bases Pages Enclosure 4: Clean-Typed TS and Bases Pages Enclosure 5: Owner's Group Letter xc: Southern Nuclear Operating Company Mr. J. T. Gasser Mr. M. Sheibani SNC Document Management U. S. Nuclear Regulatorv Commission Mr. L. A. Reyes, Regional Administrator Mr. R. R.~ Assa, Senior Project Manager, NRR Mr. John Zeiler, Senior Resident Inspector, Vogtle State of Georgia L. C. Barrett, Commissioner, Department of Natural Resources -

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ENCLOSURE 1 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECilNICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY SURVEILLANCE REQUIREMENT 3.3.2.5 BASIS FOR PROPOSED Cll ANGE Proposed Chance ,

i The current VEGP Technical Specifications (TS) specifically require quarterly testing of slave relays in the Engineered Safety Features Actuation System (ESFAS). This requirement involves testing the relays at power, with the attendant risk ofinadvertent actuation of the Engineered Safety Features (ESP) 1 equipment. In addition, the on-line testing of slave relays requires significant plant manipulation, j abnormal configurations, and removes from service various equipment, making it unavailable to perform )

its intended safety function. A subgroup of the Westinghouse Owners Group (WOG) sponsored a j reliability assessment of specific Potter & Brumfield (P&B) relay types to establish a slave relay surveillance test interval based on relay reliability. The study is documented in WCAP-13878,

" Reliability Assessment of P&B MDR Relays" The proposed change allows relaxing the Slave Relay Test from every 92 days to every 18 months for circuits containing P&B MDR series relays. The TS requirement for Slave Relay Testing will continue to be implemented by SR 3.3.2.5.

The associated Bases for Surveillance Requirement 3.3.2.5 will be revised to clarify that circuits containing P&B MDR series relays may be tested on an 18-month frequency. WCAP-13878, Revision 1, provides both the methodology and technical basis that justifies extending the surveillance frequency for ESFAS P&B MDR relays. The reliability assessment is relay specific and applies only to P&B MDR series relays.

l Basis for Proposed Channe in Surveillance Frequency l Generic Letter (GL) 93-05, "Line item Technical Specification Improvements to Reduce Surveillance Requirements for Testing During Power Operation," was approved in September 1993. This GL resulted from the recommendations of a 1983 NRC task group formed to investigate problems with surveillance testing required by TS. The objective of the NRC task group was: (1) to review the basis for test frequencies; (2) to ensure that the tests promote safety and do not degrade equipment; and (3) to review j surveillance tests for unnecessary burden on plant personnel. The studies found that while some testing {

at power is essential to verify equipment and system operability, safety can be improved, equipment i degradation decreased, and unnecessary personnel burden relaxed by reducing the amount of testing at l

' power. Slave relay test frequency relaxation is consistent with the objectis es of the NRC task group. )

WCAP-13878 contains the technical. basis and methodology for extending slave relay test requirements for ESFAS P&B MDR series relays. The technical basis and methodology were approved by letter dated May 31,1996 from Bruce A. Boger (NRC) to Tom Greene (WOG). The NRC safety evaluation report (SER) for WCAP-13878 requires confirmation of the following:

1. Verify that the genetic analysis in WCAP-13878 is applicable to their plant.

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5 ENCLOSUREI VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECIINICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY l SURVEILLANCE REQUIREMENT 3.3.2.5 BASIS FOR PROPOSED CilANGE

2. Re-evaluate the adequacy of the extended surveillance interval if two or more P&B MDR ESFAS subgroup relays fail in a 12-month period.

3. Ensure that the procurement program for P&B MDR relays is adequate for detecting the types of failures that are discussed in References 9,10,11, and 12 of the SER.

4. Ensure that all pre-1992 P&B MDR relays which are used in either a nonnally energized or a 20 %

duty cycle have been removed from ESFAS applications.

5. Perform a contact loading analysis for P&B MDR relays to determine the acceptability of the relays.

To comply with the required actions of WCAP-13878, SNC has performed the following:

Response to item 1 SNC has compared the methodology and assumptions utilized in WCAP-13878 with the SSPS system design and application of P&B MDR relays at VEGP. Based on this review, the generic analysis

- contained in WCAP-13878 !s applicable to VEGP.

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Response to item 2 Plant procedures will be revised to specifically require monitoring for P&B MDR ESFAS subgroup relay failures. If 2 or more relays fail in a 12-month period, VEGP will re-evaluate the adequacy of the extended surveillance frequency.

Response to Item 3 References 9,10,11 and 12 of the SER for WCAP-13878 identify issues related to substandard refurbishment of P&B MDR relays, and material problems in P&B MDR relays manufactured before 1992. Appropriate plant procedures have been revised to inspect new P&B MDR relays for known substandard refurbishment issues during the material receipt process. Additionally, VEGP will revise the item description in our procurement program to specify that new P&B MDR relays are manufactured after 1992. The date codes of all P&B MDR relays currently in stock will be evaluated and any that were manufactured before 1993 will be removed from stock.

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• ENCLOSURE 1 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECllNICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY SURVEILLANCE REQUIREMENT 3.3.2.5 BASIS FOR PROPOSED CIIANGE Response to Item 4 SNC has performed a detailed review of Unit 1 Train "A" and Train "B" documents. Unit I and Unit 2 are similar. The review determined that there are no normally energized ESFAS Slave Relays.

Additionally, the review determined that none of these relays are energized for a 20% duty cycle.

Item 5 A review of the contact loading of all Unit 1 Train "A" and Train "B" P&B MDR Slave Relays was performed. Unit I and Unit 2 are similar. The actual contact loadings were compared with the design contact rating for P&B MDR relays. This contact loading analysis determined that all P&B MDR Slave Relay contact loadings are within acceptable limits.

Actions for items 2 & 3 will be completed upon approval, but prior to implementation of the proposed TS change.

Auxiliary Relav Reliability Since auxiliary relays can affect the ultimate function of the slave relay to start the required equipment, auxiliary relay reliability must be comparable to that of the associated slave relay. All slave relays and their actuated devices were evaluated for the presence of auxiliary relays. The majority of VEGP slave j relays directly actuate ESF equipment, although some slave relays actuate a combination of equipment j both directly and via auxiliary relays. The functions with auxiliary relays in their actuation paths may be j divided into two groups. 1

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The Erst group consists of ESF functions where the auxiliary relays are tested during the performance of other at power TS-required surveillances. The reliability of these auxiliary relays will continue to be conGrmed every quader during the performance of these surveillances even though the associated Slave Relays are being tested on an 18-month frequency.

The second group consists of ESF functions where the auxiliary relays are not tested at power during other equipment testing. The auxiliary relays used in these circuits have been very reliable, but do not always meet the criteria presented in WCAP-13878 for relaxation of the test frequency since some are not Potter & Brumfield MDR relays. Although relaxation of the surveillance interval for the associated  ;

slave relays is justined by WCAP-13878, the auxiliary relays cannot be tested without testing the slave I relays. Therefore, quaderly testing of the associated slave relays will be administratively controlled until l an alternate method of testing the auxiliary relays is developed or until they are replaced with Potter & l Brumneld MDR series relays. I El-3

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.s ENCLOSURE 2 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY SURVEILLANCE REQUIREMENT 3.3.2.5 SIGNIFICANT IIAZARDS EVALUATION t Evaluation VEGP has evaluated the no signincant hazards considerations involved with the proposed amendment, focusing on the three standards set forth in 10 CFR 50.92(c) as quoted below:

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The Commission may make afinal determination, pursuant to the procedures in paragraph 50.91, that aproposed amendment to an operating licensefor afacility licensed underparagraph  ;

50.21(b) or paragraph 50.22 or a testingfacility involves no significant ha:ards considerations, ifoperation ofthefacility in accordwice with the proposed amendment would not:

(1) Involve a significant increase in the probability or consequences ofan accident previously evaluated; or i (2) Create thepossibility ofa new or different kind ofaccidentfrom any accident previously evaluated; or (3) Involve a sigmficant reduction in a margin ofsafety, i

The following evaluation is provided for the no significant hazards consideration standards. I

1. Does the change involve a significant increase in the probability or consequences of an accident previously evaluated?

The results of WCAP-13878 demonstrate that slave relays are highly reliable. WCAP-13878 also provides guidance to assure that slave relays remain highly reliabte. The aging assessment concludes that the age / temperature-related degradation of all ND relays, and NE relays produced after 1992, is sufficiently slow such that a refueling frequency surveillance interval will not significantly increase the probability of slave relay failures. Finally, the evaluation of the auxiliary relays actuated during slave relay testing has concluded that based on the tests of the auxiliary relays performed during other equipment testing, reasonable assurance is provided that failures will be identified if the associated slave relays are tested on a refueling frequency.

Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

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ENCLOSURE 2 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS SLAVE RELAY TEST FREQUENCY SURVEILLANCE REQUIREMENT 3.3.2.5 SIGNIFICANT HAZARDS EVALUATION i l

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2. Does the change create the possibility of a new or different kind of accident from any accident j previously evaluated?

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l The proposed changes do not alter the performance of the ESFAS mitigation systems assumed l in the plant safety analysis. Changing the interval for periodically verifying ESFAS slave

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relays (assuring equipment operability) will not create any new accident initiators or scenarios. '

Therefore, the proposed changes do not create the possibility of a new or different kind of

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accident from any accident previously evaluated for VEGP.

3. Does the change involve a significant reduction in a margin of safety?

The proposed changes do not affect the total ESFAS response assumed in the safety analysis since the reliability of the slave relays will not be significantly affected by the decreased surveillance frequency.

Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

Conclusion Based on the above safety evaluation, VEGP concludes that the changes proposed by this submittal satisfy the no significant hazards consideration standards of 10 CFR 50.92(c) and, accordingly, a no significant hazards finding isjustified.

Environmental Evaluation

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VEGP has evaluated the proposed changes and determined the changes do not involve (i) a  !

significant hazards consideration,(ii) a significant change in the types or significant increase in the )

amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or j cumulative occupational radiation exposure. Accordingly, the proposed changes meet the eligibility criteria for categorical exclusion set forth in 10 CFR S t.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), an environmental assessment of the proposed changes is not required.

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