ML19323H543
| ML19323H543 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/02/1980 |
| From: | Vissing G Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8006130112 | |
| Download: ML19323H543 (6) | |
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,tt.il.A.T.Ni'l f,3f3EI f.UM JUNE G 2 nco Docket.40. 50-313_
l FACILITY: Arkansas Nuclear One, Unit No.1 LICENSEE: Arkansas Power & Light Company
SUBJECT:
SUMMARY
OF MEETING WITH ARKANSAS POWER AND LIGHT COMPANY OF MAY 22, 1980, CONCERNING THE ARKANSAS NUCLEAR ONE, UNIT N0.
1 REACTOR COOLANT PUMP SEAL LEAK EVENT OF MAY 10, 1980 Introduction The purpose of the meeting was to review the ANO-1 RCP seal leak event of May 10, 1980, for the safety significance with respect to the con-tinued operation of ANO-1. The assigned participants of this review by the AD for Operating Reactors was the Project Management for ANO-1 and the AD for Safety Assessment, his staff and his support personnel.
The meeting followed the prepared agenda with minor modifications (En-closure 1). The attendees are identified in Enclosure 2.
Conclusions Arkansas Power & Light Company (AP&L) was requested and agreed to docu-ment in a letter to NRC prior to the next AN0-1 startup the following:
1.
The AP&L corrective action with respect to tne RCP seal repair and replacement and other damage relating to the RCP seal leak event.
2.
The AP&L commitment for a modification and early schedule of impli-mentation to move the breakers or motor control centers for the core flood tank isolation valve and nitrogen vent valves to locations outside the containment.
3.
A commitment to complete as much of the above modifications as possible to preclude the necessity to enter the containment to complete the modifications.
AP&L was informed that we would request by letter additional information relating to the RCP seal leak event, the RCP, the RCP seal, seal injec-tion system, and other motor control centers located inside the contain-ment.
A subsequent telephone conversation confirmed that AP&L would complete the committed to modifications before plant startup.
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I Discussion AP&L indicateo that during the daily leak rate check, the RCP seal staging pressure made a change at 1:45 a.m., May 10,1980. The leak rate then increased to 5 gpm, then to 30 gpm, and then to 90 gpm. At 10% power, the "C" RCP was secured and the leak rate increased to 350 gpm. The reactor was tripped and the lift pumps reduced the leak rate.
Cooldown was at the
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maximum rate (90 - 95 F/hr). At 9:00 a.m., the reactor was at cold shut-down. There was no major problem during shutdown.
The leakage from the seals prior to the event was 0.6 to 2 gpm from four There were no abnormal oscillations before shutdown or during pumps.
shutdown.
The last maintenance on the seal was in November 1979. This was a broken seal.
AP&L did not see a correlation of the seal failure to the loss of offsite l
power event of April 7,1980.
Rather they believe seal failure is more closely correlated with the number of startups and shutdowns.
AP&L indicated that the possibility of a person not being able to enter the containment to unlock the breakers which serve the core flood tank isolation valves was not a safety problem.
It would be a problem in operation.
If the isolation valves were left open during the depressuri-zation, pressure / temperature relationships would not be exce'eded'" Also there was no concern for a nitrogen bubble entering into the RC5'since there is, by Technical Specifications, enough water in the core flood tanks to still have 100 cu. ft. of water remaining when the nitrogen over-pressure decreases to atmosphere. There is no potential problem of ove pressurization of the decay heat removal system since there is an interlock at 280 psig which protects this system.
The AP&L action plan included the replacement of the seals for all four RCP's. The failed seal will be analyzed for its failure. The problem would be reviewed with the operators and maintenance personnel. Further, AP&L presented their plans for relocating the breakers or motor control centers for tne core flood tank isolation valves and nitrogen vent valves to locations outside the containment. AP&L indicated that as much of the modifications would be complete as possible before startup.
The staff identified a concern of interim operation with the vent valves inside the containment.. There is a concern that these valves should also be closed with the power to the valves removed.
.The staff identified a partial list of information which may be needed to aid in the evaluation of RCP's and RCP seals and their operation.
This infonnation would be identified and possibly requested from the licensee at a later date.
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O 3-i The staff considered it preferable to have the proposed modifications completed before startup. A subsequent telephone conversation with the I
licensee confirmed that the proposed modifications will be complete before startup.
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Criginal Signed 37 Guy Vissing, Project Manager Operating Reactors Branch #4 Division of Licensing
Enclosures:
1.
Meeting Agenda 2.
List of Attendees i
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AGENDA MEETING WITH ARKANSAS POWER & LIGHT COMPANY 9:00 a.m. - May 22, 1980 CONCERNING RCP SEAL FAILURE EVENT OF MAY 10, 1980 AT ANO-1 e
1.
Discussion of RCP seal failure and leak event with cronology 2.
History of RCP seal lea'kage at ANO - All pumps (Units 1 and 2) 3.
Status of seal prior to event a.
leak rate b.
last leak surviellance record 4.
Analysis of this seal failure as it relates to loss of offsite power event of April 7,1980 5.
Safety significance of breaker for core flood tank isolation valve inside containment and high probability a man cannot go into contain-ment to unlock and close the breaker a.
potential P/T problem b.
potential overpressurization of decay heat removal system problem c.
potential nitrogen bubble problem 6.
AP&L action pla,n 7.
Safety significance of interim operation with breakemsof the core flood tank and nitrogen vent ' valves inside containment.
8.
NRC staff, concerns 9.
NRC staff response
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c ATTENDANCE LIST FOR MEETING WITH ARKANSAS POWER & LIGHT COMPANY 9:00 A.M. - MAY 22, 1980 CONCERNING RCP SEAL FAILURE EVENT OF MAY 18,1980 AT ANO-1 NAME ORGANIZATION Guy S. Vissing NRR/DL/0RBr4 K. R. Wichman NRR/0RAB/DL J. J. Zudans NRR/EQB/ DOE D. C. Trimble AP&L Jim McWilliams AP&L John Marshall AP&L Douglas R. Sikes AP&L J. T. Beard NRC/0RAB G. C. Lainas NRC/SA Carl Michelson AEOD (part time)
J. S. Creswell AEOD Wayne Lanning AE00 Hal Ornstein AE0D Earl J. Brown AE00 John R. Fair NRR/0RAB David G. Mardis AP&L Garry G. Young ACRS Lake Barrett NRR/0RAB/DL Phil Grant NRR/DL/0RAB Ken Hoge NRR/MTEB Bob Kirkwood NRR/DE/MEB C. H. Hofmayer NRR/DE/EQB R. W. Woodruff IE M. A. McCoy SIB /DSI R. E. Martin NRR/DL/NRC Z. R. Rosztuczy NRR/DE/EQB R. W. Reid NRR/DL/0RB#4 V. W. Panciera RSB/DSI M. Chiramal ORAB F. R. Vaughan NUS Corporation Ed Jordan IE i
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MEETING SUM 4ARY DISTRIBUTION Licensee:
Mr. William Cavanaugh, III Vice President, Generation and Construction Arkansas Power & Light Company P. O. Box 551 Little Rock, Arkansas 72203 H. Denton B. Kirkwood E. G. Case C. H. Hofmayer Docket File R. W. Woodruff NRC PDR M. A. McCoy L PDR R. E. Martin Z. R. Rosztuczy TERA V. Panciera NSIC M. Chiramal
.ORBf4 Rdg E. Jordan NRR Rdg DEisenhut RTedesco TNovak Glainas ORB Branch Chiefs (5)
ORB Project Manager - G. Vissing ORB Licensing Assistant OELD AEOD IE-3 RFraley, ACRS-16 Program Support Branch Meeting Sumary File NRC Participants K. R. Wichman J. Zudans J. T. Beard Carl Michelson J. S. Creswell W. Lanning H. Ornstein E. J. Brown J. R. Fair G. G. Young, ACRS L. Barrett i
P. Grant K. Hoge
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