ML15253A432
| ML15253A432 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 02/08/1999 |
| From: | Labarge D NRC (Affiliation Not Assigned) |
| To: | NRC (Affiliation Not Assigned) |
| References | |
| GL-96-05, GL-96-5, TAC-M97075, TAC-M97076, TAC-M97077, NUDOCS 9902100293 | |
| Download: ML15253A432 (4) | |
Text
February 8, 1999 NOTE TO:
Docket File FROM:
David E. LaBarge, Senior Project Manager Project Directorate 11-2 Division of Reactor Projects - 1/11 Office of Nuclear Reactor Regulation
SUBJECT:
PRELIMINARY REQUEST FOR ADDITIONAL INFORMATION - OCONEE NUCLEAR STATION UNITS 1, 2, AND 3 (TAC NOS. M97075, M97076, M97077)
Attached is a memorandum from the Mechanical Engineering Branch of NRR requesting additional information from the licensee, Duke Energy Corporation.
Docket Nos. 50-269, 50-270, and 50-287 Distribution:
PUBLIC 9902100293 990208 PDR ADOCK 05000269 P
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-001 January 20, 1999 MEMORANDUM TO: Herbert N. Berkow, Director 4
Project Directorate 11-2 Division of Reactor Projects 1/11 FROM:
David Terao, Chief Components & Testing Section Mechanical Engineering Branch Division of Engineering
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION REGARDING GENERIC LETTER 96-05 PROGRAM AT OCONEE (TAC NOS. M97075, M97076 AND M97077)
On September 18, 1996, the NRC issued Generic Letter (GL) 96-05, "Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves," to request that nuclear power plant licensees establish a program, or ensure the effectiveness of the current program, to verify on a periodic basis that safety-related motor-operated valves (MOVs) continue to be capable of performing their safety functions within the current licensing basis of the facility.
On March 31, 1998, Duke Power Company (licensee of Oconee Nuclear Station, Units 1, 2, and 3) submitted an updated response to GL 96-05 indicating its intent to implement the provisions of a Joint Owners Group (JOG) Program on MOV Periodic Verification at Oconee.
The NRC staff has encouraged licensees to participate in the industry-wide JOG program to provide a benefit in reactor safety by sharing expertise and information on MOV performance and to increase the efficiency of GL 96-05 activities at nuclear plants. Licensee participation in the JOG program also minimizes the amount of information necessary for the NRC staff to review each licensee's response to GL 96-05. As a result, the NRC staff requires only limited information to complete its GL 96-05 review for Oconee.
Attached is a request for additional information regarding the GL 96-05 program at Oconee that should be forwarded to the licensee. It is requested that the licensee's response be provided within 60 days of the forwarding letter.
Docket Nos. 50-269, 270, and 287
Attachment:
As stated CONTACT:
T. Scarbrough, DE/EMEB 415-2794
REQUEST FOR ADDITIONAL INFORMATION ON RESPONSE OF OCONEE NUCLEAR STATION TO GENERIC LETTER 96-05
- 1.
In NRC Inspection Report No. 50-269, 50-270, & 50-287/95-25, the NRC staff closed its review of the motor-operated valve (MOV) program implemented at Oconee Nuclear Station (Oconee) 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 the licensee's MOV program to be addressed over the long term. For example, the inspectors noted that (1) the licensee had committed to improve the margins for eleven Unit 2 and Unit 3 valves by the end of 1996; (2) the licensee would be expected to review applicable information following completion of the NRC staff's evaluation of the Electric Power Research Institute (EPRI) MOV Performance Prediction Methodology (PPM) and to take appropriate action, as necessary; and (3) the PPM model needed to be validated for Powell gate valves with inverted-guides and Crane gate valves with non-stellite seating material. In addition, NRC Inspection Report No. 50-269, 50-270, & 50-287/97-05 (dated July 18, 1997) noted that the licensee planned to (1) replace or dynamically test butterfly valve 1 CC-7; and (2) conduct a prototype flow test to justify the assumed valve factor applied to Velan gate valve 2FDW-1 04. The licensee should provide a summary status of the actions taken to address the specific long-term aspects of the MOV program at Oconee noted in the two NRC inspection reports.
- 2.
In a letter dated May 13, 1998, the licensee updated 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 previous letter dated March 18, 1997, the licensee stated that the ranking of MOVs at Oconee would be based on the Westinghouse Owners Group (WOG) Engineering Report V-EC-1 658-A (Revision 0) and/or the Boiling Water Reactor Owners' Group (BWROG) methodology as described in BWROG Topical Report NEDC 32264, "Application of Probabilistic Safety Assessment of Generic Letter 89-10 Implementation." As the Oconee units are pressurized water reactors (PWRs) designed by Babcock & Wilcox (B&W), the licensee should describe the application of the WOG or BWROG methodology to Oconee, including (1) the preparation of a sample list of high-risk MOVs from other B&W nuclear plants, and (2) consideration of the conditions and limitations discussed in the NRC safety evaluation dated April 14, 1998, on the WOG methodology, or the NRC safety evaluation dated February 27, 1996, on the BWROG methodology.
- 3.
The licensee should briefly describe its plans for the use of test data from the motor control center (MCC) including (1) correlation of new MCC test data to existing direct force measurements; (2) interpretation of changes in MCC test data to changes in MOV thrust and torque performance; (3) consideration of system accuracies and sensitivities to MOV degradation for both output and operating performance requirements; and (4) validation of MOV operability using MCC testing.
ATTACHMENT
- 4.
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. The licensee should describe the plan at Oconee for ensuring adequate ac and dc MOV motor actuator output capability, including consideration of recent guidance in Limitorque Technical Update 98-01 and its Supplement 1.
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