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Mary Jane Ross-Lee, ChiefOperating Experience Branch
Tools Used to Collect, Screen, Communicate and Analyze Operating Experience (OpE)
Data
Improving Nuclear Safety ThroughOperating Experience Feedback
Cologne, GermanyMay 30, 2006
May 30, 2006 2
NRC OpE Program Objectives
OpE is collected, evaluated, communicated, and applied to support the NRC’s goal of ensuring safety
OpE is used to improve the effectiveness, efficiency, and realism of NRC decisions
Stakeholders are provided with timely, accurate, and balanced information
May 30, 2006 3
NRC Reactor OpE
Program supports regulatory decision-making in our core programs Licensing Oversight Incident Response Rulemaking Physical Security
Based on inter-dependent model where all organizations work toward applying OpE
May 30, 2006 4
Reactor OpE Review Process
Current OpE Program launched January 2005
Centralized screening organization Various sources of OpE collected Screening of domestic and international
OpE in accordance with established guidelines
Evaluation of screened-in items by Clearinghouse team and technical staff
Communication with stakeholders Analysis/trending of all OpE Application of OpE lessons learned
May 30, 2006 5
Reactor OpE ProgramInput-Output Overview
Collection
Screening
Communication
Evaluation
Application
Incident Reporting System(IRS)
Internal Nuclear Event Scale(INES)*
International OpE
Daily Events Reports*Plant Status Reports*
Licensee Event Reports*Part 21 Reports*
Domestic OpE: Industry
Inspection Findings*Morning Reports*
Preliminary Notifications*Regional Project Calls
Studies/Trends
Domestic OpE: NRC
OpE ClearinghouseGeneric Communications
Morning ReportsOpE Briefings
COMMunicationsWeb Page
Informing Stakeholders
InspectionLicensing
Influencing Agency programs
RulemakingInformation Request
Taking Regulatory Actions
Storage
* - available to public
May 30, 2006 6
Overview of OpE Process – 4 Phases
May 30, 2006 7
Reactor OpE Program - 2005
Over 1000 specific OpE items screened 127 OpE COMMunications to technical
experts 30 OpE issues evaluated and closed 7 OpE senior management briefings All daily reports evaluated for INES rating 66 Generic Communications (e.g., IN, GL,
RIS) issued 30 technical groups formed to review OpE
May 30, 2006 8
International Activities
International Nuclear Event Scale (INES) All daily Event Notifications (10 CFR 50.72s)
rated with INES Level 2 or higher is communicated
internationally 2 events submitted in 2005
Incident Reporting System (IRS) Relevant Generic Communications submitted
to IRS IRS reports are reviewed in screening process 20 US reports submitted in 2005 out of 70 total
May 30, 2006 9
Information Technology Tools
OpE Information Gateway Single web access point to multiple databases Dataset assumptions and limitations explained Improved OpE search capabilities
@Operating Experience Community Web-based communication forum Subscription notification to over 30 topical
groups Provides links to related documents Searchable records
May 30, 2006 10
May 30, 2006 11
OpE Community Posting
May 30, 2006 12
Technical Review Group (TRG)
Agency-wide initiative to supplement Clearinghouse screening Clearinghouse processes over 1000 items Technical experts have more specific
knowledge Identifies issues that were overlooked
30 TRGs created covering various technical areas with members from key offices and regions
Groups consisted of: Pumps & Valves, Fuel, Electrical, Piping, etc.
May 30, 2006 13
What Does the TRG Review?
Each TRG reviews relevant OpE data sources specific to the technical discipline.
OpE data sources include: OpE COMMs which are emailed to members
and posted on the OpE Community Forum Inspection Findings Licensee Event Reports International OpE Part 21 reports INPO SEE-IN documents
May 30, 2006 14
TRG Output TRG reviews OpE in their area over the last 6
months From the initial review, several issues were
identified 3 Generic Documents Initiated
Information Notice (IN) on diesel generator problems including corrosion issues and wear caused by non-lubricated starts
IN on emergency preparedness siren system failures caused by a single siren failure providing continuous feedback signal
IN on silt, biofouling and debris causing blockage and equipment failure
2 High Priority Followups Flow induced vibration problems Reactor coolant pressure boundary degradation mechanisms
12 Open Items
May 30, 2006 15
TRG Benefits
Previously unidentified issues or trends identified
NRC technical experts used for review
Increased the use of OpE in the technical groups and the regional offices
Minimal resources required for benefit gained
May 30, 2006 16
Accident Sequencer Precursor
Established 1979, in Office of Research
Staff reviews LERs to identify potential precursors
Three agency programs assess risk – ASP, SDP, M.D 8.3
Challenges of ASP - timeliness for analysis, looking at graded approach
May 30, 2006 17
ASP Search Results
May 30, 2006 18
Upcoming OpE Activities
Developing international ties in the areas of new reactor construction
Improving OpE search capabilities
May 30, 2006 19
Publicly Available OpE Reports Associated with Events (
http://www.nrc.gov/reading-rm/doc-collections/event-status/)
Power Reactor Status Event Notification Report Morning Report Part 21 Reports Preliminary Notifications
Generic Communications (http://www.nrc.gov/reading-rm/doc-collections/gen-comm/index.html)
Bulletins Generic Letters Information Notices Regulatory Issue Summaries
May 30, 2006 20
References (in ADAMS) http://www.nrc.gov/reading-rm/adams.html
Management Directive 8.7 (ML043570013)
MD 8.7 Handbook (ML043570032)
NRR Office Instruction LIC-401 (ML050130014)
Reactor Operating Experience Task Force Report (ML033350063)
Plan for Implementing Reactor Operating Experience Task Force Report (ML041180024)
Recent OpE Examples
Quad Cities ERV Vibration Issues
Palo Verde Shutdown Cooling Isolation Valve Vibration
May 30, 2006 22
Recent OpE Example 1
Vibration-Induced Failure of Electromatic Relief Valves (ERVs) at Quad Cities
Quad Cities 1 and 2 Generic Electric Boiling Water Reactors Mark I containment Commercial operation started in 1973 Extended power uprate (EPU) of 17.8%
(446 Mwt) approved in 2001
May 30, 2006 23
Event Summary – Unit 2
December 30, 2005: Internal damage of the ERV actuator found; plant shutdown initiated
Significant wear and loose parts identified on remaining 3 actuators
January 14, 2006: Unit 2 shutdown for inspection of the actuator pivot plate bolts (due to Unit 1 issue)
May 30, 2006 24
Event Summary – Unit 1
December 31, 2005: Unit 1 decreased to pre-EPU power due to Unit 2 issue
January 6, 2006: plant shutdown initiated
Three ERVs had unsuccessful stroke tests or inspection results
January 15, 2006; Unit 1 shutdown for inspection of the turnbuckle (Unit 2 had weld cracking)
May 30, 2006 251
Shown installed in Drywell
Actuator
Pilot Valve
ERV
Electromatic Relief Valve
May 30, 2006 26
As-found Conditionsof ERV Parts
Plunger
Actuator
Post Plunger Roller
May 30, 2006 27
Safety Significance
Degraded capability for overpressure protection/depressurization
Preliminary risk assessment: Conditional Core Damage Probability = 2.7E-6
Three Green Findings
May 30, 2006 28
NRC Response
Close monitoring by resident inspectors Preliminary Notification - January 17,
2006 Special Inspection - January 9 through
February 7, 2006 Internal communications of the event Issue For Resolution: Screened-in for
operating experience follow-up
May 30, 2006 29
Recent OpE Example 2
Shutdown Cooling Isolation Valve Vibration at Palo Verde 1
Palo Verde 1 Combustion Engineering
Pressurized Water Reactor Commercial operation started in
1986
May 30, 2006 30
Event Summary
Vibration problem since 2001 Worsened following steam generator
replacement December 2005: Vibration of Train A
shutdown cooling suction line reached administrative limit
Plant reduced power to less then 35%
May 30, 2006 31
Event Summary cont.
The licensee has attempted several modifications to reduce the vibration, but none have been fully successful added masses added supports added heating blankets installed a flow distribution plate
Since March 17, 2006: Plant maintenance outage ongoing
May 30, 2006 32
Affected valve
May 30, 2006 33
Safety Significance
Degraded shutdown cooling train Shutdown cooling system used for low
pressure heat removal
Significant operational constraint
May 30, 2006 34
NRC Response
Close monitoring by resident inspectors
Internal communications of the event
Issue For Resolution: Screened-in for operating experience follow-up
May 30, 2006 35
Questions & Comments