ML063200408
| ML063200408 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 12/05/2006 |
| From: | Bhalchandra Vaidya NRC/NRR/ADRO/DORL/LPLIV |
| To: | Venable J Entergy Operations |
| Vaidya B, NRR/DORL/LP4, 415-3308 | |
| Shared Package | |
| ML063210023 | List: |
| References | |
| Download: ML063200408 (5) | |
Text
December 5, 2006 Mr. Joseph E. Venable Vice President of Operations Entergy Operations, Inc.
River Bend Station 5485 US Highway 61N St. Francisville, LA 70775
SUBJECT:
RIVER BEND STATION, UNIT 1 - RE: FINAL ACCIDENT SEQUENCE PRECURSOR ANALYSIS OF DECEMBER 2004 OPERATIONAL EVENT, LER 458/04-005-01
Dear Mr. Venable:
Enclosed are the final results of the Accident Sequence Precursor (ASP) analyses of an event which occurred at River Bend Station, Unit 1 (RBS), as documented in Licensee Event Report (LER) 458/04-005-01. The subject event occurred on December 10, 2004, during which RBS experienced a reactor trip due to loss of a non-vital 120V instrument bus and was reported in LER 458/04-005-01. The ASP analysis (Agencywide Documents Access and Management System (ADAMS) Accession No. ML062710038) calculated a mean conditional core damage probability of 2.7 x 10-5.
The Nuclear Regulatory Commission (NRC) established the ASP Program in 1979 in response to the Risk Assessment Review Group report (see NUREG/CR-0400, dated September 1978).
The ASP Program systematically evaluates U.S. nuclear power plant operating experience to identify, document, and rank the operating events that were most likely to have led to inadequate core cooling and severe core damage (precursors), accounting for the likelihood of additional failures.
The ASP Program has the following objectives:
Provide a measure for trending nuclear power plant core damage risk.
Provide a partial check on dominant core damage scenarios predicted by probabilistic risk assessments.
Provide feedback to regulatory activities.
Evaluate the adequacy of NRC programs.
The NRC also uses the ASP Program to monitor performance against the safety goal established in the agency's Strategic Plan (See NUREG-1100, Vol. 21, dated February 2005).
J. Venable For more information about the ASP Program, see the annual ASP Program Report at http://www.nrc.gov/reading-rm/doc-collections/commission/secys/2005/secy2005-0192/2005-01 92scy.pdf.
The enclosure is provided for your information and no response is requested.
If you have any questions, please contact me at 301-415-3308.
Sincerely,
/RA/
Bhalchandra Vaidya, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-458
Enclosure:
Final ASP Analysis cc w/encl: See next page
Package ML063210023 (Letter ML063200408, Enclosure ML062710038)
OFFICE NRR/LPLIV/PM NRR/LPLIV/LA RES/DRASP/D NRR/LPLIV/BC NAME BVaidya LFeizollahi FEltawila DTerao DATE 11/28/06 11/27/06 11/1/06 11/30/06
November 2006 River Bend Station cc:
Manager, Licensing Entergy Operations, Inc.
River Bend Station 5485 US Highway 61N St. Francisville, LA 70775 Director, Nuclear Safety & Licensing Entergy Operations, Inc.
1340 Echelon Parkway Jackson, MS 39213-8298 Louisiana Department of Environmental Quality Radiological Emergency Planning and Response Division P.O. Box 4312 Baton Rouge, LA 70821-4312 Louisiana Department of Environmental Quality Office of Environmental Compliance P.O. Box 4312 Baton Rouge, LA 70821-4312 Senior Resident Inspector P.O. Box 1050 St. Francisville, LA 70775 President of West Feliciana Police Jury P.O. Box 1921 St. Francisville, LA 70775 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 Ms. H. Anne Plettinger 3456 Villa Rose Drive Baton Rouge, LA 70806 Executive Vice President and Chief Operating Officer Entergy Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 General Manager Plant Operations Entergy Operations, Inc.
River Bend Station 5485 US Highway 61N St. Francisville, LA 70775 Director, Nuclear Safety Assurance Entergy Operations, Inc.
River Bend Station 5485 US Highway 61N St. Francisville, LA 70775 Vice President, Operations Support Entergy Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 Mr. Jim Calloway Public Utility Commission of Texas 1701 N. Congress Avenue Austin, TX 78711-3326 Attorney General State of Louisiana P.O. Box 94095 Baton Rouge, LA 70804-9095 Brian Almon Public Utility Commission William B. Travis Building P.O. Box 13326 1701 North Congress Avenue Austin, Texas 78701-3326 Richard Penrod, Senior Environmental Scientist/State Liaison Officer Office of Environmental Services Northwestern State University Russsell Hall, Room 201 Natchitoches, LA 71497