ML20198G994

Forwards Request for Addl Info Re Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety- Related Motor Operated Valves Program

ML20198G994
Person / Time
Site:	Beaver Valley
Issue date:	12/22/1998
From:	Dan Collins NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
GL-96-05, GL-96-5, TAC-M97015, TAC-M97016, NUDOCS 9812290214
Download: ML20198G994 (4)

Text

1.

December 22, 1998 MEMORANDUM TO: Docket File FROM:

Daniel S. Collins, Project Manager

/s/

Project Directorate 1-2 Division of Reactor Projects - 1/II Office of Nuclear Reactor Regulation l

SUBJECT:

BEAVER VALLEY POWER STATION, UNIT NOS 1 AND 2, DRAFT i

REQUEST FOR ADDITIONAL INFORMATION, GENERIC LETTER (GL) 96-05, PERIODIC VERIFICATION OF DESIGN-BASIS CAPABILITY OF SAFETY-RELATED MOTOR OPERATED VALVES, PROGRAM (TAC NOS. M97015 AND M97016) l The attached draft request for additional information (RAl) was transmitted by facsimile on December 22,1998, to Frank Ferri of Duquesne Light Company. Review of the RAI would allow the licensee to determine and agree upon a schedule to respond to the RAl. This memorandum and the attachment do not convey a formal request for information or represent an NRC staff positi q.

l Docket Nos. 50 F# < and 50-412.

Attachment:

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December 22, 1998

.....p MEMORANDUM TO: Docket File w

FROM:

Daniel S. Collins, Project Manager JE Project Directorate 1-2 Division of Reactor Projects - 1/Il Office of Nuclear Reactor Regulation

SUBJECT:

BEAVER VALLEY POWER STATION, UNIT NOS 1 AND 2, DRAFT REQUEST FOR ADDITIONAL INFORMATION, GENERIC LETTER (GL) 96-05, PERIODIC VERIFICATION OF DESIGN-BASIS CAPABILITY OF SAFETY-RELATED MOTOR OPERATED VALVES, PROGRAM (TAC NOS. M97015 AND M97016)

The attached draft request for additional information (RAl) was transmitted by facsimile on December 22,1998, to Frank Ferri of Duquesne Light Company. Review of the RAI would allow the licensee to determine and agree upon a schedule to respond to the RAl. This memorandum and the attachment do not convey a formal request for information or represent an NRC staff position, i

Docket Nos. 50-334 and 50-412.

Attachment:

As stated i

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DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO GENERIC LETTER 96-05 FOR BEAVER VALLEY POWER STATION. UNIT NOS.1 AND 2.

DOCKET NOS. 50-334 AND 50-412 1.

In NRC Inspection Report No. 50-344 & 412/95-12, the NRC staff closed its review of the motor-operated valve (MOV) program implemented at the Beaver Valley Power Station, Unit Nos.1 and 2 (BVPS-1 and BVPS-2), in response to Generic Letter (GL) 89-10," Safety-Related Motor-Operated Valve Testing and Surveillance." In the inspection report, the NRC staff discussed certain aspects of Duquesne Light Company's (DLC's) MOV program to be addressed over the long term. For example, the inspectors noted that (1) DLC's periodic verification program will gather additional data to support the use of a 10% load sensitive behavior margin; (2) DLC planned to increase the thrust margin for the Unit 1 quench spray pump discharge valves prior to the end of the next refueling outage; (3) DLC relied on available valve factors in some cases where the assumed valve factors did not have strong support; and (4) DLC's periodic verification program will gather additional data to determine if stem lubricant degradation is occurring. Please describe the actions taken to strengthen group valve factor assumptions and address the specific long-term aspects of the MOV program at BVPS-1 and BVPS-2 noted in the subject NRC inspection report.

2.

In a letter dated November 18,1996, DLC stated its commitment to implement the Joint Owners Group (JOG) Program on MOV Periodic Verification in response to GL 96-05.

The JOG program specifies that the methodology and discrimination criteria for ranking MOVs according to their safety significance are the responsibility of each participating licensee. In a subsequent letter dated April 13,1998, DLC stated that risk ranking of MOVs at BVPS-1 and BVPS-2 for application of the JOG interim MOV static diagnostic testing program will be based on guidance provided in Westinghouse Owners Group (WOG) Engineering Report V-EC-1658-A (Revision 1)," Risk Ranking Approach for Motor-Operated Valves in Response to Generic Letter 96-05," with some stated exceptions. For example, DLC stated that (1) MOVs were only ranked based on Core Damage Frequency (CDF) importance measures, (2) only MOVs not modeled in the probabilistic risk assessment (PRA) were reviewed by the expert panel, (3) the PRA analyst used his judgment to review the quantitative ranking based on PRA CDF importance measures, and (4) MOVs that were only modeled as passive failures were ranked based on CDF, and then qualitatively reassessed by the PRA analyst. These exceptions do not appear to reflect the importance of the expert panel as described by WOG Engineering Report V-EC-1658-A and the NRC safety evaluation dated April 14, 1998. DLC should describe the composition and duties of the expert panelin risk ranking MOVs at BVPS-1 and BVPS-2. With respect to each of its specific exceptions, DLC should justify that its MOV risk-ranking approach is consistent with the guidance contained in WOG Engineering Report V-EC-1658-A and the NRC safety evaluation. In light of its exceptions to the WOG MOV risk-ranking approach, please discuss consideration of the example list of risk-significant MOVs provided by the WOG in the engineering report.

ATTACHMENT

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DRAFT

3.,

The JOG program focuses on the potential age-related increase in the thrust or torque required to operate valves under their design-basis conditions. In the NRC safety evaluation dated October 30,1997, on the JOG program, the NRC staff specified that licensees are responsible for addressing the thrust or torque delivered by the MOV motor actuator and its potential degradation. Please describe the plan at BVPS-1 and BVPS-2 for ensuring adequate ac and de MOV motor actuator output capability, including consideration of recent guidance in Limitorque Technical Update 98-01 and its Supplement 1.

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