ML17292B559
| ML17292B559 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 02/11/1999 |
| From: | Poslusny C NRC (Affiliation Not Assigned) |
| To: | Parrish J WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| References | |
| TAC-M96928, NUDOCS 9902180339 | |
| Download: ML17292B559 (7) | |
Text
February 11, 1999 Mr. J. V. Parrish Chief Executive Officer Washington Public Power Supply System P.O. Box 968 (Mail Drop 1023)
Richland, Washington 99352-0968
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SUBJECT:
REQUEST FOR ADDITIONALINFORMATIONFOR THE WASHINGTON PUBLIC POWER SUPPLY SYSTEM (WPPSS) - NUCLEAR PROJECT NO. 2 (WNP-2) (TAC NO. M96928)
Dear Mr. Parrish:
The staff recently audited WNP-2 files supporting the use.of the GOTHIC code to support the technical specification changes requested'by your October 15, 1996, submittal and supplemental letter dated December 4, 1997,'pertaining to the secondary containment and standby gas treatment system drawdown and post accident'analysis.
Based on this effort and review of your submittals, the staff has determined that the additional information identiTied in the enclosure is needed to complete the review.
These questions were discussed with Mr. Paul Inserra of your staff on February 10, 1999, and it was mutually agreed that you would provide a response to this request within 60 days of receipt of this letter.
Ifyou have any questions, please contact me at (301) 415-1341.
Sincerely, Original Signed By Chester Poslusny, Senior Project Manager Project Directorate IV-2 Division of Reactor Projects III/IV Office of Nuclear Reactor Regulation Docket No. 50-397
Enclosure:
Request for Additional Information cc w/encl: See next page DOCUMENT NAME: RAI2GOT DISTRIBUTION:
Docket File PUBLIC PDIV-2 Reading EAdensam (EGA1)
WBateman CPoslusny EPeyton OGC LSmith, Region IV KBrockman, Region IV JKudrick RPederson OFC PDIV-2/
NAME CPoslusn DATE 2/ I I/99 PDIV-2/
EPe on 2/ i ~/99 OFFICIAL RECORD COPY F'P02i80339' 70211 PDR ADGCK 05000397 P
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Mr. J. V. Parrish February 11, 1999 cc w/encl:
Mr. Greg O. Smith (Mail Drop 927M)
Vice President, Generation Washington Public Power Supply System P. O. Box 968 Richland, Washington 99352-0968 Mr. Albert E. Mouncer (Mail Drop 1396)
Chief Counsel Washington Public Power Supply System P.O. Box 968 Richland, Washington 99352-0968 Ms. Deborah J. Ross, Chairman Energy Facility Site Evaluation Council P. O. Box 43172 Olympia, Washington 98504-3172 Mr. D. W. Coleman (Mail Drop PE20)
Regulatory Affairs Manager Washington Public Power Supply System P.O. Box 968 Richland, Washington 99352-0968 Mr. Paul Inserra (Mail Drop PE20)
Manager, Licensing Washington Public Power Supply System P.O. Box 968 Richland, Washington 99352
.Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Harris Tower & Pavilion 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 Chairman Benton County Board of Commissioners P.O. Box 69 Prosser, Washington 993504190 Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 69 Richland, Washington 99352-0968 Mr. Rodney L. Webring (Mail Drop PE08)
Vice President, Operations Support/PlO Washington Public Power Supply System P. O. Box 968 Richland, Washington 99352 Perry D. Robinson, Esq.
Winston & Strawn 1400 L Street, N.W.
Washington, DC 20005-3502
RE VEST FOR ADDITIONALINFORMATION WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PROJECT NO. 2 DOCKET NO. 50-397 A loss of offsite power ( LOOP) has been assumed for the selected analyses.
The conservatism of this assumption should be justified since the normal heat load would be much higher than the loads considered under LOOP conditions. Without such supporting justification, a case including offsite power should be added to the case matrix.
2.
Many of the files refer to GOTHIC as a best estimate code.
Since the analyses represent design basis accident (DBA) conditions, provide a discussion of the safety margins that are available to change the best estimate results to conservative results.
Material provided on the docket indicates the in-leakage rate is established based on a linear relationship with pressure.
This is the most conservative approach.
However, the files show leakage based on a best fit of the data taken from secondary containment tests.
This data shows that the actual leakage response is somewhere between linear and the square root of pressure.
Verifythat the linear relationship has been used for the reanalysis.
The docketed material indicates that a primary to secondary leakage rate of 0.5%/day has been included in the analysis.
However, within the files there is evidence that this leakage has been neglected.
Indicate what was assumed.
Ifneglected, show why it will not impact the results The reanalysis assumes that the initial pressure is at zero gauge.
The current analysis assumed an initial pressure of a negative 0.25 inch water gauge.
Therefore, the technical specifications (TSs) contain daily surveillance of secondary containment pressure.
The proposal deletes all pressure surveillance.
However, there remains a need to assure that positive pressure is never achieved.
Under the proposed deletions it is unclear as to how assurance can be provided that positive pressures are never reached.
Address how this condition would become known without any pressure surveillance.
6.
Although the TSs are being changed, the Final Safety Analysis Report (FSAR) willnot be changed as part of this request.
For consistency, the FSAR should be also modified along with the TSs.
Confirm that this willbe the approach.
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It is indicated that the standby gas treatment (SGT) system willnot be initiated until 2 minutes after the loss of coolant accident ( LOCA). Describe why it is taking so long to start the SGT.
8.
Figure 3: WNP-2 Design Basis Meteorology states: 'Meteorology Enveloped by this Curve>95%. The lower starting point of the curve reflects 0 wind speed and 0 degrees F. Please discuss the source of this curve and why the assumptions are conservative.
It has been indicated that the GOTHIC code has been validated by comparing the results of a high energy line break (HELB) event in the secondary containment with results using RELAP This is not appropriate since the event is not applicable to the secondary containment response without a high'energy line break. The validation needs to compare results to similar conditions.
For example, data taken during normal ventilation system operation could be used to compare with a GOTHIC analysis.
Therefore, an acceptable method of validation should be provided for this application of the GOTHIC code.
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