ML13303B854
| ML13303B854 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/23/1987 |
| From: | Rood H Office of Nuclear Reactor Regulation |
| To: | Baskin K, Holcombe J San Diego Gas & Electric Co, Southern California Edison Co |
| References | |
| GL-83-028 NUDOCS 8707290093 | |
| Download: ML13303B854 (4) | |
Text
2 ' JUL 1981 Docket Nos.: 50-361 and 50-362 Mr. Kenneth P. Baskin Mr. James C. Holcombe Vice President Vice President -
Power Supply Southern California Edison Company San Diego Gas & Electric Company 2244 Walnut Grove Avenue 101 Ash Street Post Office Box 800 Post Office Box 1831 Rosemead, California 91770 San Diego, California 92112 Gentlemen:
SUBJECT:
RAI RELATING TO GENERIC LETTER 83-28, GENERIC APPLICATION OF THE SALEM ATWS EVENT Item 4.2 of Generic Letter 83-28 requires licensees and applicants to describe their preventative maintenance and surveillance program for ensuring reliable reactor trip breaker operation. Parts 1 and 2 of Item 4.2 pertain to a program of periodic maintenance of the breakers and the measurement and trending of parameters affecting their operation. By letter dated March 25, 1986, you responded to a staff request for additional information dated December 13, 1985. Review of that response has disclosed the need for additional information as described in the enclosure herein.
We request that you provide the additional information at your earliest convenience. If you have any questions regarding this request please contact me.
Sincerely, D0iina SIg1ned by Harry Rood Harry Rood, Senior Project Manager Project Directorate V Division of Reactor Projects -
- III, IV, V and Special Projects
Enclosure:
DISTRIBUTION RAI Docket File NRC & Local PDRs cc:
See next page PD#5 Plant File GHolahan JLee/HRood OGC-Bethesda EJordan/JPartlow ACRS(10)
DRSP/PDV DR PDV HRood:cd GWfig hton 7/ /..87 7/ 3/87 OFFICIAL RECORD COPY 9707290093 870723 PDR ADOCK.0500036 1
Mr. Kenneth P. Baskin San Onofre Nuclear Generating Southern California Edison Company Station, Units 2 and 3 cc:
Mr. James C. Holcombe Mr. Hans Kaspar, Executive Director Vice President - Power Supply Marine Review Committee, Inc.
San Diego Gas & Electric Company 531 Encinitas Boulevard, Suite 105 101 Ash Street Encinitas, California 92024 Post Office Box 1831 San Diego, California 92112 Mr. Mark Medford Southern California Edison Company Charles R. Kocher, Esq.
2244 Walnut Grove Avenue James A. Beoletto, Esq.
P. 0. Box 800 Southern California Edison Company Rosemead, California 91770 2244 Walnut Grove Avenue P. 0. Box 800 Mr. Stephen B. Allman Rosemead, California 91770 Manager, Nuclear Department San Diego Gas'& Electric Company Orrick, Herrington & Sutcliffe P. 0. Box 1831 ATTN:
David R. Pigott, Esq.
San Diego, California 92112 600 Montgomery Street San Francisco, California 94111 Richard J. Wharton, Esq.
University of San Diego School of Alan R. Watts, Esq.
Law Rourke & Woodruff Environmental Law Clinic 701 S. Parker St. No. 7000 San Diego, California 92110 Orange, California 92668-4702 Charles E. McClung, Jr., Esq.
Attorney at Law Mr. S. McClusky 24012 Calle de la Plaza/Suite 330 Bechtel Power Corporation Laguna Hills, California 92653 P. 0. Box 60860, Terminal Annex Los Angeles, California 90060 Regional Administrator, Region V U.S. Nuclear Regulatory Commission Mr. C. B. Brinkman 1450 Maria Lane/Suite 210 Combustion Engineering, Inc.
Walnut Creek, California 94596 7910 Woodmont Avenue, Suite 1310 Bethesda, Maryland 20814 Resident Inspector, San Onofre NPS c/o U. S. Nuclear Regulatory Commission Mr. Dennis F. Kirsh Post Office Box 4329 U.S. Nuclear Regulatory Commission SanClemente, California 92672 Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Mr. Dennis M. Smith, Chief Radiological Programs Division Governor's Office of Emergency Services 2800 Meadowview Road Sacramento, California 95832
REQUEST FOR ADDITIONAL INFORMATION ITEM 4.2 (PARTS 1 AND 2) OF GENERIC LETTER 83-28 SAN ONOFRE NUCLEAR GENERATING STATION, UNITS 2,3 Item 4.2 of Generic Letter 83-28 requires licensees and applicants to describe their preventative maintenance and surveillance program for ensuring reliable reactor trip breaker operation. Parts 1 and 2 of Item 4.2 pertains to a program of periodic maintenance of the breakers and the measurement and trending of para meters affecting their operation.
The primary criteria for an acceptable periodic maintenance program are contained in "Maintenance Instruction GEI-50299EI, Power Circuit Breakers, Types AK-2/2A-15, AK-2/3/2A/3A-25, AKU-2/3/2A/3A-25," and Service Advice 175-9.3S and 175-9.20, by General Electric. The NRC staff has reviewed these items and endorsed the main tenance program they describe. The criteria include those items in the General Electric instructions and advisories that relate to the safety function of the breaker, supplemented by those measurements which must be taken to accumulate data for trending.
In a request for information dated December 23, 1985, the NRC staff identified 13 items for maintenance at six month intervals that should be included in the licensee's reactor trip breaker (RTB) maintenance program. By letter dated March 25, 1986, the licensee confirmed that each of the 13 items was included in their periodic maintenance program except for the following:
- 7. Verification that the trip torque required on the trip shaft is less than 1.5 pound-inches, as specified in Service Advice 175-9.3S, Item #S4; "Before" and "After" maintenance torque values should be recorded;
- 10. Lubrication of trip shaft and latch roller bearings with Mobil 28 lubricant.
-2 The licensee states that trip torque verification is not performed "After" maintenance on the basis that SCE believes response time testing is superior to trip torque measurements as a predictive parameter in providing information on breaker degradation. No scientific or statistical analysis is presented to sup port the licensee's belief. The licensee should commit to the trip torque veri fication measurement after maintenance, or present evidence that such a measure ment is of no value in assessing the operability of the breaker thereafter.
The licensee states that lubrication of the trip shaft and latch roller bearings with Mobil 28 lubricant is not warranted for the San Onofre Units 2 and 3 RTBs because the RTBs have sealed trip shaft and latch roller bearings. We find this response to be acceptable.
In the request for information dated December 13, 1985; the NRC staff also identi fied four parameters for trending. The licensee committed to trending of the breaker response time for the undervoltage trip, but declined to include (1) under voltage trip attachment dropout voltage, (2) breaker insulation resistance or, as discussed above, (3) trip torque. The licensee stated that the dropout voltage and resistance measurements were recorded, but not trended, on the basis that the licensee did not believe that predictive information could be derived from a trend analysis for these parameters. The licensee should provide scientific or statistical evidence to support their belief. As an alternative, the NRC staff could find acceptable a program wherein the licensee not only recorded the three parameters, but compared them to the manufacturer's recommended values or ranges, and took appropriate action accordingly.