ML030280481
| ML030280481 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 11/20/2002 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| Download: ML030280481 (16) | |
Text
pj-F O 1-
-1O United States Nuclear Regulatory Commission Davis-Besse Reactor Vessel Head Degradation Lessons-Learned Task Force Public Meeting November 20, 2002 I
Meeting Agenda
"* Introduction and Opening Remarks
"* Overview
"* Results
"* Recommendations
"* Future Activities
"* Discussion/Questions
"* Closing Remarks Art Howell Ed Hackett Ed Hackett Ed Hackett Art Howell All Art Howell 2
Overview
Background
- NRC has taken the initiative to conduct lessons-learned reviews for significant issues
, Self-critical
, Improvements made Examples:
"* Indian Point 2 steam generator tube failure (2000)
"* NRC inspections at the South Texas Project (1995) 3
Overview Objectives and Scope
"* Perform independent evaluation
"* Review:
, Reactor oversight process
, Regulatory processes
, Research activities International practices
"* Identify and recommend improvements 4
Overview Composition and Attributes
"* Multi-disciplined, experienced team
"* No previous significant involvement in Davis-Besse Nuclear Power Station (DBNPS) oversight
"* Observation by State of Ohio
"* Stakeholder input to task force review activities o Solicited input at two public meetings 5
Overview Review Methods
"* Comprised of two groups
"* Performed document reviews and conducted interviews
"* Conducted fact finding at DBNPS site
"* Conducted reviews at NRC Regional and Headquarters Offices 6
Overview Report
"* The report is available on ADAMS (the NRC electronic document management system)
- Accession number: ML022760414
"* The report is also available on the NRC's public website http://www.nrc.gov/reactors/operating/ops experience/vessel-head-degradation/news, html
"* The report issuance was coordinated with other NRC offices because of ongoing NRC reviews DBNPS plant-specific issues were provided to the NRC's 0350 Oversight Panel for follow up, as appropriate 7
Results Overall Conclusions
"* NRC and industry recognized potential for this type of event nearly 10 years ago
"* Initial conclusion was that vessel head penetration nozzle cracking was not an immediate safety concern
"* NRC and DBNPS failed to learn key lessons from past boric acid-induced degradation events S
Results Overall Conclusions (continued)
The leaking nozzle and vessel head degradation event was not prevented
- The NRC, DBNPS, and the nuclear industry failed to adequately review, assess, and follow up on relevant operating experience
- DBNPS failed to assure that plant safety issues would receive appropriate attention
- The NRC failed to integrate known or available information into its assessments of DBNPS's safety performance 9
Results Overall Conclusions (continued)
- Other contributing factors Guidance and requirements Staffing and resources
- DBNPS communications Licensing processes and implementation 10
Results NRC and Industry Review, Assessment, and Follow up of Operating Experience
"* Significant operating experience involving boric acid leakage and corrosion
"* Generic Communication Program implementation
"* Generic Issues Program implementation
"* Operating experience involving foreign nuclear power plants
"* Assessment and verification of industry technical information
"* NRC operating experience review and assessment capability 11
Results DBNPS Assurance of Plant Safety
- Reactor coolant system leakage symptoms and indications
- Boric acid corrosion control program and implementation
- Owners group and industry guidance
- Internal and external operating experience awareness
- Oversight of safety related activities 12
Results NRC Assessment of DBNPS Safety Performance
"* Reactor coolant system leakage assessment
"* Inspection program implementation
"* Integration and assessment of performance data
"* Guidance and requirements
"* Staffing and resources
"* Davis-Besse Nuclear Power Station communications
"* Licensing process guidance and implementation 13
Recommendations Recommendation Areas
"* Inspection guidance
"* Operating experience assessment
"* Code inspection requirements
"* NRC programs and capabilities (including training and experience)
"* Leakage monitoring requirements and methods
"* Technical information and guidance
"* NRC licensing processes
"* Previous NRC lessons-learned reviews 14
Future Activities Senior Management Review Team
"* The Senior Management Review Team is reviewing the report's recommendations
"* Plans are being established for addressing the recommendations
"* Actions are already underway to implement some of the recommendations 15
Closing Remarks Summary
- The NRC conducted a comprehensive, self-critical assessment of its regulatory processes as a result of the DBNPS degraded reactor vessel head.
- The NRC identified a number of areas for improvement and has initiated actions to address these areas.
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