ML052140326
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ML052140326 | |
Person / Time | |
---|---|
Site: | South Texas ![]() |
Issue date: | 03/09/2005 |
From: | Schinzel G South Texas |
To: | Office of Nuclear Reactor Regulation |
References | |
Download: ML052140326 (8) | |
Text
RIC 2005 Session WA3 Risk-Informing Special Treatment Requirements 10 CFR 50.69 Insights from the 50.69 Proto-type Pilot Plant Glen Schinzel, Project Manager Risk Implementation , STPNOC - South Texas Project March 9, 2005 361-972-7854 geschinzel@stpegs.com
Background of STPs Status
- STP pursued and received an Exemption from certain Special Treatment Requirements in August 2001 - viewed as proto-type pilot for 10 CFR 50.69
- STP categorization process and implementation allowances closely align with the processes approved in 10 CFR 50.69
- As of 12/31/04, STP completed categorization of 85 different system designators (about 80,000 components) 2
Categorization Lessons Learned Positives noted:
- Consensus decision-making process has been effective in promoting critical discussion and consensus resolutions
- Excellent categorization stability has been noted throughout process
- Good consistency noted between probabilistic and deterministic results
- Dissenting Opinion process has worked well -
differences of technical opinions effectively addressed
- Management involvement adds value to the process 3
Categorization Lessons Learned Challenges seen:
- Proper identification of all system functions is necessary for effective categorization results
- Electrical components (breakers, MCCs, etc) pose unique categorization challenges when determining importance
- If a certain number of components are not specifically tagged, need to develop methodology on how to address these in both categorization and implementation 4
Categorization Lessons Learned Hazards to be Avoided:
- Begin with a well-reviewed, well-supported PRA Model
- Recognize that some SSCs will periodically change categorization - prepare a methodology to restore full regulatory controls to SSCs that were previously RISC-3
- Documentation of categorization basis must be detailed, clear, and retrievable
- Categorization and treatment must be addressed separately
- Must prepare the organizational culture to understand and use the categorization results 5
Implementation Lessons Learned
- Communicate, communicate, communicate
- Focus on a few programmatic areas of implementation initially - when these areas show positive feedback with controlled results, move on to other areas
- Focus on programmatic areas that have a willing owner
- Determine how to define implementation success -
could be defined through reduced burden, parts savings, better focus on safety significant activities, etc.
6
Implementation Lessons Learned
- STP is expending considerable effort to document a basis of reasonable confidence when reducing treatment for RISC-3 SSCs - question as to whether 50.69 requires this same degree of effort
- There remains uncertainty about NRC expectations for industry RISC-3 treatments - when will the industry feel comfortable with what constitutes reasonable confidence, and who will define it?
7
Going Forward
- STP efforts to date have demonstrated the value of a sound categorization approach
- Implementation results in both nuclear safety and economic benefits - not all can be measured via bottom-line, hard-dollar savings
- Categorization and treatment are different aspects and must be kept separate
- Industry is poised to move forward, but uncertainties still exist that could keep many industry players on the sidelines 8