ML13317A225
| ML13317A225 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/14/1982 |
| From: | Baskin K Southern California Edison Co |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8207160142 | |
| Download: ML13317A225 (6) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 K. P. BASKIN TELEPHONE MANAGER OF NUCLEAR ENGINEERING, 213) 572-1401 SAFETY, AND LICENSING July 14, 1982 Director, Office of Nuclear Reactor Regulation Attention:
D. M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Review of Draft Operating Experience Report San Onofre Nuclear Generating Station Unit 1
Reference:
Letter from W. A. Paulson, NRC, to Mr. R. Dietch, SCE, dated May 12, 1982 Enclosed with the referenced letter was a draft review of the operating experience history for San Onofre Unit 1. That report compiles into one document a history of San Onofre 1 operating experience based on reportable occurrences, licensee event reports, etc. We have reviewed the factual basis for this document as requested and have identified several errors or misinterpretations and have made clarifications as detailed in the enclosure to this letter.
The purpose of this review was to assure that the facts on which the report are based are complete and correct. The corrections in the enclosure complete this task. However, it appears that as the data was compiled into the body of the report, some loss of clarity occurred. SCE is, therefore, performing a more in-depth review of the document to assure that it more clearly characterizes the operating experience at San Onofre 1. We expect to provide you with additional comments on the conclusions stated in the report by August 12, 1982.
We understand that the information contained in this report may be used to support conclusions made during the integrated assessment. If you have questions regarding our review of the factual basis of this report, please contact me.
Very truly yours, Enclosure 8207160142 820714 PDR ADOCK 05000206 P
Enclosure COMMENTS ON NRC DRAFT REPORT ON SAN ONOFRE 1 OPERATING EXPERIENCE INTRODUCTION The operating experience of San Onofre Unit 1 is reviewed in the Referenced document. That report was prepared by the Nuclear Safety Information Center of the Oak Ridge National Laboratory to be used to support conclusions made during the integrated assessment of San Onofre 1. The document was forwarded to SCE for comment on May 12, 1982.
This document provides SCE's comments and clarification of the factual basis of the Oak Ridge report. Several errors were identified in the body of the report while the appendices were accurate with only minor errors in dates and wording. In a few instances it appears that as the appendices were translated into the body they were rearranged leading to an inaccurate portrayal of the actual event.
attempt has been made in this report to assess the conclusions of the report.
The following details SCE's comments on the Operating Experience Report. In each case the page, line number, and section number is provided with the corrections and comments.
SECTION NO.
PAGE LINE STATEMENT IN REPORT CORRECTED REVISION COMMENTS 1.4 1-14 16 Routine radioactivity releases Routine radioactivity releases There were no releases where were tabulated as well, and were tabulated as well and are limits were exceeded. Section releases where limits were discussed in Section 4.5.1.4.
4.5.1.4 discusses releases, not exceeded were reviewed and are 4.6 discussed in Section 4.6.
3.1.2 3-6 15 The closure of a main steam Complete deletion There are no main steam isolation valve....
isolation valves at San Onofre 1.
4.2 4-1 19
...with 430 MWe net generating
...with 436 MWe net generating SONGS 1 is rated at 436 MWe net capacity.
capacity.
maximum.
4.4.1 4-5 9
Review of reactor shutdowns and (No change)
This section apparently did not power reductions.
consider the outage from September 30, 1976 to April 11, 1977 to install the emergency diesel generators, construct the sphere enclosure building and perform a reactor internals inspection (4532 hours0.0525 days <br />1.259 hours <br />0.00749 weeks <br />0.00172 months <br />).
-2 SECTION NO.
PAGE LINE STATEMENT IN REPORT CORRECTED REVISION COMMENTS 4.4.1.1 4-5 24 The saltwater in-leakage The turbine blade failure sent Condenser failure did not cause resulted in significant turbine metal fragments into the turbine blade failure as blade damage.
condenser causing saltwater stated.
leakage.
4.4.1.1 4-8 12 These are recurring events in These were recurring events in Dropped rods are no longer a San Onofre's operating history.
San Onofre's early operating recurring problem.
history.
4.4.1.1 4-8 17
...the unit shut down....
...the unit was manually tripped....
4.4.1.1 4-8 18
...inadvertent closure of the The date for this event was not tsunami gate occurred on specified as it was for others.
November 1, 1967.
4.4.1.1 4-8 22
...when a fire....
...when a cable overload This clarifies the cause of the fire....
fire.
4.4.1.1 4-9 19 On...October 10, the unit On...the unit shutdown...to There is no indication of the shutdown...to replace leaking.... replace leaking....
plant being down on October 10 due to leaking PRV's.
4.4.1.1 4-9 25 On October 14, a relay On October 14, a relay Plant shutdown was due to malfunction casued several malfunction caused several valve failure and not control control rods to drop. The control rods to drop.
Failure rod drop as implied.
unit was down for 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br />.
of a recirculation valve motor winding caused the plant to be shut down for 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br />.
4.4.1.1 4-10 2
The first, on May 29, was a The first, on May 29, was a The operator tripped the reactor trip due to turbine reactor trip caused by a turbine and because 2 of 4 acceleration which was faster turbine trip after the operator power channels indicated than desired.
tripped the turbine due to an greater than 10% power, the acceleration rate greater than reactor was also tripped.
desired.
4.4.1.1 4-10 3
The second, on November 23....
(Delete total statement.)
The November 23 outage was a scheduled outage.
-3 SECTION NO.
PAGE LINE STATEMENT IN REPORT CORRECTED REVISION COMMENTS 4.4.1.1 4-10 24
...tripped on a steam generator
...tripped due to a turbine High steam generator water high level signal.
trip caused by high steam level does not directly cause generator water level, a reactor trip.
4.4.1.1 4-11 19
...a power reduction occurred
...an indication of a dropped The power reduction was resulting from an indication rod during a condenser cleaning necessary for condenser of a dropped rod, power reduction, cleaning.
4.4.1.1 4-12 15
...down for 101 of the 1978
...down for 101 of the 178 The unit was down only 178 hours0.00206 days <br />0.0494 hours <br />2.943122e-4 weeks <br />6.7729e-5 months <br />...,
hours....
hours.
4.4.1.1 4-12 24
...four events involving
...four events involving The problems were due to turbine overspeed.
turbine overspeed resulting settings being to light.
from incorrect turbine trip settings.
4.4.1.1 4-13 6
There were three events of There were two events of actual There were only two events of actual dropped rods on dropped rods on May 18 and actual dropped rods.
The April 14, May 18, and June 9.
June 9. On April 14 there was April 14 event was only an an erroneous indication of a indication and not an actual dropped rod dropped rod.
4.4.1.1 4-13 14 On March 2 and une 9, the On June 9, the unit reduced There was no power reduction on unit reduced power....
power....
March 2 to plug leaking condenser tubes according to the monthly report.0 4.4.1.1 4-13 23 November 29, twice on
.. November 29 and twice on There was no power reduction November 30 and December 2) ovember 30) involving December 2 to repair involving condenser tube leaks.
condenser tube leaks.
condenser tube leaks.
4.4.1.2(2) 4-15 5
...resulted from major salt-
...resulted from turbine blade See comments on page 4-5, water in-leakage resulting in damage resulting in saltwater line 24.
turbine blade damage.
in-leakage.
-4 SECTION NO.
PAGE LINE STATEMENT IN REPORT CORRECTED REVISION COMMENTS 4.4.1.3 4-16 19
...which occurred on August 28,
...which occurred on August 18, Incorrect data.
1978.
1978.
4.4.2.7 4-23 4
Inadvertent operation of Operation of ECCS....
The ECCS worked as designed ECCS....
though no flow was required.
4.4.2.7 4-23 9
...resulted in the unnecessary
...resulted in the initiation Same as above.
initiation of the safety of the safety injection system.
injection system.
4.4.3.2 4-26 5
Six additional shutdowns...
Six additional shutdowns...
The purpose of the shutdow tested the overspeed setting were done to test the over-was for the tests.
speed setting....
4.4.3.4 4-28 9
...problem related to power
...problems related to power There is no Section 4.4.3.5.
buses and inverters and are buses and inverters.
discussed in Section 4.4.3.5.
4.5.1.1 4-32 5
In addition to those events, (Complete deletion.)
The flywheel replacement was this review also included a done as a maintenance item and reactor coolant pump event in should therefore not appear in which the pump flywheel this section.
cracked.
4.5.1.1 4-32 15 Of the remaining 13 events, Of the remaining 13 events, This clarifies the origin of 4 involved the reactor trip 4 involved the reactor trip some of these events.
system....
system (3 of the overspeed events were part of the Westinghouse test)....
4.5.1.1 4-35 23 A second significant event A second significant event Loss of salt water cooling was occurred in March, 1980 when occurred in March, 1980 when not due entirely to pump all the salt water cooling pump and valve failures failures.
pumps available for the caused the salt water cooling plant failed.
system to be interrupted for 15 minutes.
-5 SECTION NO.
PAGE LINE STATEMENT IN REPORT CORRECTED REVISION COMMENTS 4.5.2.4 4-51 7
A potential loss of emergency A potential loss of emergency Both diesel generators did not AC power was revealed when AC power was revealed when each fail at the same time or even failure of both diesel of the two diesel generators during the same test.
generators was experienced in failed at different times the semi-annual...
during the semi-annual....
4.5.3.1 4-57 16 The spike recurred three more A spare channel drawer was times.
installed in NIS channel 1207 and operated overnight. These occurrences of spiking were observed with the spare in 0
services.
4.5.3.3 4-62 16 All involved leakage past the Leakage on July 6 and The sources of leakage are plugs with inflatable seals September 22 was not secondary clarified.
used to keep water and foreign to primary leakage. The material from entering the September 1 incident was reactor coolant system. On secondary to primary leakage July 6, a boron dilution of but was attributed to a leaking 400 ppm from 3357 to 2957 ppm block valve in the FW and resulted during decontamination.
condensate system.
Dilution of On September 1, a 35 ppm 400 ppm from 3357 to 2957, dilution occurred and on 35 ppm dilution and 51 ppm September 23, a 51 ppm dilution. dilution occurred on July 6, September 1, and September 22 respecti vely.
Appendix A A-10 6
...removed from service to
...removed from service to The outage was for the pure repair a pressurizer spray....
conduct routine turbine tests of turbine tests, not due to and reactor training startups.
the maintenance activities.
Maintenance during the outage was done to repair a pressurizer spray....
Reference:
Review of the Operating Experience History of San Onofre 1 through 1980 for the Nuclear Regulatory Commission's Systematic Evaluation Program by to Nuclear Safety Information Center of the Oak Ridge National Laboratory, dated May 1982.
JHammond:e4793