ML17347B680
| ML17347B680 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee, Diablo Canyon, 05000000 |
| Issue date: | 03/27/1987 |
| From: | Novak T Office of Nuclear Reactor Regulation |
| To: | Asselstine, Bernthal, Carr, Roberts, Zech NRC COMMISSION (OCM) |
| Shared Package | |
| ML17347B681 | List: |
| References | |
| CON-#287-2970, REF-GTECI-082, REF-GTECI-NI, TASK-082, TASK-82, TASK-AS, TASK-BN87-005, TASK-BN87-5, TASK-OR BN-87-005, BN-87-5, OLA, NUDOCS 8704060312 | |
| Download: ML17347B680 (11) | |
Text
~4
~o
~0 C
I 0
IA0 0
~O t
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 March 27, 1987 Docket Nos.
50-275 and 50-323 MEMORANDUM FOR:
FROM:
SUBJECT:
Chairman Zech CoIIIIissioner Roberts Commissioner Asselstine CQMiissioner Bernthal Comnissioner Carr Thomas M. Novak, Acting Directnr Division of PWR Licensing-A BOARD NOTIFICATION REGARDING BNL DRAFT REPORT ON SPENT FUEL POOL ACCIDENTS,(BN 87-05)
In accordance with NRC procedures for Board Notification fRN} we are providing for your information the following enclosed Brookhaven (BNL) draft report:
"Beyond Design-Basis Accidents in Spent Fuel Pools (Generic Issue 82},"
Department of Nuclear Energy, Brookhaven National Laboratory, Draft, January 1987, transmitted by letter from K. R. Perkins (BNL) to E. Throm (NRC}, dated February 5, 1987.
The report addresses the risk of spent fuel storage at nuclear power plants and includes an evaluation of accident initiating events and their probabilities, fuel cladding failure scenarios arising from uncertainties in Zircaloy oxidation reaction rate data, and the potential for releases of radionvclides vnder various cladding failvre scenarios.
The draft report presents the results of a study performed by BNL for the staff on Generic Issue 82, "Beyond Design-Basis Accidents in Spent Fuel Pools."
The draft report has been distributed widely within the staff for a peer review.
Like most of the Generic Issues and Unresolved Safety Issues currently being studied by the staff, the likelihood of beyond desian basis accidents is being examined to assess whether.vulner-abilities could exist which might require further consideration of changes ir'esign or operations.
Preliminary staff opinion is that substantial portions of the report will need more critical review because some assumptions appear to be oversimplified.
Comments will be provided to BNL.and the final report is expected to be issued this sumIer.
The contractor states, based on these preliminary results, that the risk from spent fuel pools is comparable to the risk from core melts in general.
The spent fuel pool risk is primarily due to postulated fires from self-sustaining oxidation of the Zircaloy cladding of the spent fuel stored fn high-density racks if wate~- is lost from the pool.
The dominant causes of water loss are or b
an due to structural failures of the pool caused by droppino of a sp nt f 1 cask y
earthouake.
However, all of the estimates of the factors affecting the risk are preliminary and the report is less an estimate of the risk than identification of the factors that need further study in order to make a
reasonably accurate estimate o< risk.
is likel Based on a brief review, the staff exoects'hat the final result f th y to provide a much lower estimate of risk.
The risk.estimate in the o
e study report is not based on an analysis of the structural 'capability of fuel pools, but of similar concrete structures.
Furthermore.
the report effectively assumed that failure of the pool would result in the loss of inteqritv of the pool liner without considering whether the strain would be sufficient to fail the liner.
Based on other seismic risk studies, the fuel pool could require a much stronger, and therefore less probable, earthquake than that required tn fail the systems necessary to control reactivity and cool a core.
Failure a few plants.
'due to a cask drop is not likely now since casks are used infrequentl t
1 en y a on y The report also assumes that all of the cesium would be released from the equivalent of three cores if a Zircaloy fire occurred.
While the spent fuel in a pool has less of the short half-life fission products than a fresh core, this would primarily only affect estimates of early fatalities.
However, in the anal.vsis of the fraction of cesium released from the spen. fuel, it was assumed that all of the fuel was at the maximum calculated clad temperature.
1f the radial and axial temperature distribution were considered, the calcu-lated release fraction would likely be less, possibly by a factor of two.
The report also assumes no retention of cesium in the fuel pool building.
Even if an earthouake destroyed the building, the debris would likely cause much of buildin s a
the cesium to be retained.
Other studies of the cesium t ti i
g and the large fraction of cesium retained at Chernobyl indicate that the report may underestimate retention by a factor of ten.
Overall the report may overestimate the risk from fuel pools by a factor of about 200..
The draft report does not pertain directly to currently ongoing licensing efforts for spent fuel pool expansion amendment requests by utilities, including hearings.
- However, we believe that the subiect may involve substantial public, press or-Congressional interest.
For this reason we are providing you with the enclosed report.
Me also are providing the report, by copy of this Board Notification, to the Boards and Service Lists for the Diablo Canvon Plant and Yermont Yankee Station.
Re will inform vou of further developments.
Enclosure:
As stated Thomas H. Novak, Ac irector Division of PNR Licensing-A cc:
See next oaqe
Mr. J.
D. Shi ffer Pacific Gas and Electric Company Diablo Canyon 0
cc:
Richard F: Locke, Esq.
Pacific Gas 8, Electric Company Post'Office Box 7>42 San Francisco, California 94120 Janice E. Kerr, Esq.
California Public Utilities Comission 350 McAllister Street San Francisco, California 94102 Ms. Sandra A. Silver 660 Granite Creek Road Santa Cruz, California 95065 I
Mr. W. C. Gangloff Westinghouse Electric Corporation P. 0.
Box 355 Pittsburqh, Pennsylvania 15230 Managing Editor San Luis Obispo County Telegram Tribune 1321
)ohnson Avenue 1?26 M Street, N.W.
Suite 1100 Washington, DC 20036-450P Mr. Leland -M. Gustafson, Manaqer Federal Relatinns Pacific Gas and Electric Company 1726 M Street, N ~
W.
Washington, DC 20036-4502 Dian M. Grueneich, Esq.
Edwin F. Lowry, Esq.
Grueneich"h Lowry 345 Franklin Street San Francisco, California 94102 NRC Resident Inspector Diablo Canyon Nuclear Power Plant c/o V.S. Nuclear Regulatory Commission P. 0.
Box 369 Avila Reach, California 934P4 Mr. Dick Rlakenburg Editor 8 Co-Publisher South County Publishing Company 0.
Box 460 Arroyo Grande, California 93>PO Bruce Norton, Esq.
c/o Richard F. Locke, Esq.
Paci~ic Gas and Electric <ompany Post Office Box ?44P.
San Francisco, California 94120 Dr. R.
BE Ferguson Siera Club - Santa Lucia Chapter Rocky Canyon Star Route Creston, California 93437 Chairman San Luis Obispo County Board of Supervisors Room PPO County Courthnuse Annex San Luis Obispo, California 93401 Director Energy Facilities Siting Divisicn Energy Resources Conservation and Development Commission 1516 9th Street Sacramento, California 95814 Ms. ilacquel.vn Wheeler 2455 Leona Street San Luis Obispo, California 934o0
0
Pari<ic Gas It Electric Company Diablo Canvon CC:
Ms. Laurie McDermott. Coordinator Consumers Organized for Defense of Environmental Safety 731 Pacific Street, Suite 42 San Luis Obispo, California 93401 Mr. Joseph
- 0. Hard, Chief Radiological Health Branch State Department of Health Services 714 P Street, Office Building f8 Sacramento, California 95814 Ms. Nancy Culver 192 Luneta Street San Luis Obispo, California 93401 President California'ublic Utilities Commission California State Buildina 350 YcA11ister Street San Francisco, California 94'.02 Reoional Administrator, Region V
U.S. Nuclear Regulatory Commission 1450 Maria Lane Suite 210 walnut Creek, California 94596
Pacific Gas and Electric Companv Diablo Canyon CC:
Glenn 0. Bright Administrative Judge Atomic Safety and Licensinq Board U.S. nuclear Reoulatory Comnission
'Rashinoton, DC 20555 Qr. Jerry Harbour Administrative Judge Atomic Safety and Licensing Board U.S. Nuclear Regulatory Commission Mashington, DC 20555 B. Paul Cotter, Jr.,
Chairman Administrative Judge Atomic Safety and Licensing Board V.S. Nuclear Regulatory Conmission k'ashington, DC 20555
Mir. R.
M. Capstick Vermont Yankee Nuclear Power Corporation Vermont Yankee Nuclear Power Station CC:
Mr. J.
G. Meigand President 5 Chief Executive Officer Vermont Yankee Nuclear Power Corp.
R.
D. 5, Box 169 Ferry Road Brattleboro, Vermont 05301 Mr. Donald Hunter, Vice President Vermont Yankee Nuclear Power Corp.
1671 Morcester Road Framingham, Massachusetts 0)70)
New England Coalition on Nuclear Pollution Hill and Dale Farm R.
D. 2, Box 223
- Putney, Yermont 05346 Hr. Walter Zaluzny
- Chairman, Board of Selectman Post Office Box 116 Vernon, Vermont 05345 Mr. J.
P. Pelletier, Plant Manager Yermont Yankee Nuclear Power Corp.
Post Office Box 157 Vernon, Vermont 05354 Hr. Raymond N. HcCandless Vermont Division of Occupational 8 Radiological Health Administration Building 10 Baldwin Street Montpelier, Vermont 05602 Honorable John J.
Easton Attorney General State of Vermont 109 State Street Montpelier, Vermont 05602 John A. Ritscher, Esquire Ropes 8 Gray 225 Franklin Street Boston, Massachusetts 02110 Hr. M. P. Murphy, Vice. President 5
Manager of Operations Vermont Yankee Nuclear Power Corp.
R. D. 5, Box 169 Ferry Road Brattleboro, Yermont 05301 Hr. Gerald Tarrant, Commissioner Vermont Department of Public Service 120 State 'Street Hontpelier, Yermont 05602 Public Service Board State of Vermont 120 State Street Hontpelier, Vermont 05602 Vermont Yankee Decommissioning Alliance Box 53 Montpelier, Vermont 05602-0053 Resident Inspector U. S. Nuclear Regulatory Commission Post Office Box 176 Vernon, Vermont 05354 Vermont Public Interest Research Group, Inc.
43 State Street Montpelier, Vermont 05602 Regi ona1 Administrator, Region I U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvar:ia 19406 Ellyn R. Weiss Harmon 5 Weiss 200) S. Street, N.
W.
Suite 430 Washington, D.C. 20009-1125 Office of the Attorney General 1 Ashburton Place 19th Floor Boston, Massachusetts 02108 0
Vermont Yankee Nuclear Power Corporation Vermont Yankee Nuclear Power St'ation CC:
Charles Bechhoefer, Chairman Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Commission Washington, DC 20555 Glenn 0. Bright Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Comoission Washington, DC 20555 James H. Carpenter Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Commission Washington, DC 20555