ML20150C923
| ML20150C923 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 07/06/1988 |
| From: | Varga S Office of Nuclear Reactor Regulation |
| To: | Wilgus W FLORIDA POWER CORP. |
| References | |
| CAL, NUDOCS 8807130216 | |
| Download: ML20150C923 (4) | |
Text
I o,,
UNITED STATES NUCLEAR REGULATORY COMMISSION o
{
,I wAsm NGTON, D. C. 20665 July 6, 1988 Docket No. 50-302 Mr. W. S. Wilgus Vice President, Nuclear Operations Florida Power Corporation ATTN: Manager, Nuclear Licensing P. O. Box 219 Crystal River, Florida 32629
Dear Mr. Wilgus:
SUBJECT:
CONFIRMATORY ACTION LETTER - CRYSTAL RIVER 3 - EMERGENCY FEEDWATER SYSTEM OVERTEMPERATURE DUE TO CHECK VALVE LEAXS On June 21, 1988, Florida Power Corporation (FPC) staff informed the NRC verbally that a normally cold portion of the emergency feedwater (EFW) line at Crystal River Unit 3 (CR-3) had heated up to approximately 490'F, well beyond its 110'F design temperature, due to bonnet leakage from check valve EFV-18 and seat leakage through contair. ment isolation check valve FWV-43. The EFW contain-ment penetration was heated above its design temperature, the surrounding concrete also reached elevated temperatures, and one pipe anchor was damaged.
An interim modification was implemented which reduced the EFW line temperature to approximately its normal value.
System walkdowns, tests and examinations, and preliminary thermal analyses reportedly indicated that no damage resulted which would prevent the EFW system and containment isolation system from performing their safety functions.
By letter dated June 28, 1988, FPC docketed a justification for continued operation (JCO) which documented information on this matter.
Subsequent to submittal of the JCO, the bonnet leak at EFV-18 reportedly was stopped by injection of sealant and the interim modification was no longer being used.
Based on continuing assessment of this information, the NRC staff concluded that continued operation was acceptable while FPC and the NRC staff were assessing the problem, with the interim uodification or with the EFV-18 bonnet leak stopped with sealant.
On July 3,1988, the staff was informed that the bonnet of valve EFV-33 had a small leak, indicating leakage past the seat in check valve EFV-16. Although line temperatures did not increase significantly, the interim modification I
referred to above was re-actuated to maintain normal line temperatures. On-line repair of EFV-33 is being pursued.
l l
8807130216 800706 h
R ADOCK 050 2
g I
w i
Mr..W. S. Wilgus July 6, 1988 During a telephone call on July 3,1988, FPC comitted to shut down the facility no later than October 15, 1988 to evaluate check valves in the EFW system and effect necessary permanent repairs. An FPC letter dated July 5,1988 confirmed this comitment and described actions to be taken during this shutdown.
Based on FPC's July 5,1988 letter and previous information, and contingent on receipt of acceptable information identified below, we conclude that operation with the temporary modification in place and/or with bonnet leaks repaired with injected sealant or otherwise, is acceptable until October 15, 1968. EFW line temperature at the penetration and functioning of the interim modification should continue to be verified heurly.
By October 15, 1988, or earlier if a Mode 5 out-age were to occur prior to that time, bonnet leaks should be permanently repaired and check valves with known leakage past the seat inspected and repaired as necessary to restore the system to its original design basis.
If the system evaluation indicates that other check valves may be similarly damaged, they should also be inspected and repaired.
The letter confirms our understanding that FPC has comitted to accomplish the above actions, and to provide the following information by July 8,1988:
1.
A discussion of the effect of potential EFW system degradation on the reliability of the system and on long-term plant safety, 2.
A description of the repair of EFV-33 and of the injected sealant repair of EFV-18, results of the repairs, and description and results of t'esting to verify component / system operability after repairs.
3.
The results of all thermal and stress analyses of all involved piping, penetrations, and supports.
4.
Evaluation of 'he safety implications of the valve leakage and EFW system overtemperaturt and of the EFW system with the interim fix and the temporary repaics in place.
5.
Verification that EFW components have not been damaged by overtemperature events and can reliably perform their safety functions.
6.
A discussion of the possible need for a more comprehensive inspection and repair program based on an evaluation of current and past valve leakages.
If the above does not accurately reflect your comitment and other agreements, please inform this office imediately.
As an additional matter, it appears that FPC may not have taken adequate corrective action upon recognition of the leak in EFV-18 in January 1988 and of the leak in FWV-43 in May 1988, and may have failed to pursue verification of system integrity et the time of previous EFW overtemperature events referenced in the JCO. You are requested to provide a chronology of all check valve leakage events in both EFW trains, and a discussion of the review performed and actions taken at the time when EFV-18 bonnet leakage was identified, when the EFW line temperature was observed to rise, when the temperature of the EFW line suddenly increased, and when the temporary fix was installed.
Provide the same information for the previous EFW overtemperature events.
If 50.59 evaluations were performed, furnish copies of these.
v j
s b
a.
-Mr.lW.S.Wilgus
.- 3
~
July 6, 1988 The above information is expected to be provided to the NRC staff to form the basis for,the meeting scheduled at 10:00 A.M. on July.8, 1988 in the NRC
.Rockville of fices. -
'The reporting and/or recordkeeping requirements contained in this letter affect
- fewer than 10 respondents; therefore, ONB clearance is not required pursuant to P.L.96-511.
Sincerely, Original signed by Steven A. Varga, Director Division of Reactor Projects I/II Office of Nuclear Reactor Regulation cc: See next page-DISTRIBUTION-( N.?
HRC & Local PDRs PDII-2 Rdg.
THurley/JSneizek,12/G/18 FHiraglia,12/G/18 SVarga,14/E/4 Glainas, 14/H/3
-JRichardson,8/H/3 AThadani, 7/E/4 LReyes, RII HBerkow DHiller HSilver OGC BGrirnes, 9/A/2 EJordan, 3302 MNB8 ACRS(10)
Gray File See previous concure ces on 50.54(f) letter.*
LA:PDII-2 FM:Pt
-2 D:
2 ADR2*
AD/E*
DMiller HSilvJr:bd H
Glainas JRichar so 07/ /88 07/g/88 07/
88 06/30/88 06/30/88j g AD/S*
RII*
.R AThadani LReyes a
06/30 8 07/01/88 07
/88 yd 0
4 hfun
t fir. W. S. Wilgus Crystal River Unit No. 3 Nuclear Florida Power Corporation Generating Plant cc:
Mr. R. W. Neiser State Planning and Development Senior Vice President Clearinghouse and General Counsel Office of Planning and Budget Florida Power Corporation Executive Office of the Governor P. O. Box 14042 The Capitol Building St. Petersburg, Florida 33733 Tallahassee, Florida 32301 Mr. P. F. ficKee Mr. F. Alex Griffin, Chairman Director, Nuclear Plant Operations Board of County Comissioners Florida Power Corporation Citrus County P. O. Box 219 110 North Apopka Avenue Crystal River, Florida 32629 Inverness, Florida 36250 Mr. Robert B. Borsum Mr. E. C. Simpson Babcock & Wilcox Director, Nuclear Site Nuclear Power Generation Division Florida Power Corporation Support 1700 Rockville Pike, Suite 525 P.O. Box 219 Rockville, Maryland 20852 Crystal River, Florida 32629 Resident Inspector U.S. Nuclear Regulatory Commission 15760 West Powerline Street Crystal River, Florida 32629 Regional Administrator, Region II U.S. Nuclear Regulatory Comission 101 Marietta Street N.W., Suite 3100 Atlanta, Georgia 30323 Jacob Daniel Nash Office of Radiation Control Department of Health and Rehabilitative Services 1317 Winewood Blvd.
Tallahassee, Florida 32399-0700 Administrator Department of Environmental Regulation L
Power Plant Siting Section State of Florida 2600 Blair Stone Road Tallahassee, Florida 32301 Attorney General Department of Legal Affairs The Capitol Tallahassee, Florida 32304
.