ML24278A268
| ML24278A268 | |
| Person / Time | |
|---|---|
| Issue date: | 10/04/2024 |
| From: | Zeechung Wang NRC/RES/DRA/PRB |
| To: | |
| References | |
| Download: ML24278A268 (3) | |
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NRC INTERNATIONAL MEETING
SUMMARY
Meeting
Title:
Technical Meeting on Probabilistic Safety Assessment for Non-Reactor Nuclear Facilities
Meeting Dates: 09/09/2024 - 09/13/2024
Visited or Visiting Country: Netherlands
Participant(s):
Jonathan Marcano Lozada (He/Him/His) - NMSS Zeechung (Gary) Wang - RES/DRA
Meeting Summary:
I was nominated by Christian Araguas and Mehdi Reisi Fard of RES/DRA directors participated in a Technical Meeting on Probabilistic Safety Assessment for Non-Reactor Nuclear Facilities in the Netherlands. This is the first meeting in the past few years for discussing PSA of non-reactor facilities. This event was held in Amsterdam, Kingdom of the Netherlands, from 9 to 13 September 2024.
The objective of the event is to provide the platform for discussions on experiences regarding the wide range of aspects of risk assessment for non-reactor nuclear facilities (using probabilistic and other risk analysis techniques). Special emph asis will be given to the existing experiences and best practices in this area and understanding the limitations of using traditional, well established PSA methods for these facilities.
The nominees for the technical meeting should be representatives of regulatory bodies, operating organizations, design organizations, technical support organizations, research or governmental institutes and industry, that are actively involved in safety demonstration for non-reactor nuclear facilities.
As an attendee representing the NRC, I provided a presentation with topic: Risk Metrics on Non-Reactor Nuclear Facilities. One of the primary areas of my presentation is the analysis of risk metrics development to support the risk-informed program for spent fuel transportation and Non-light water reactors (NLWR). I also presented the methods of LMP that the NRC used to develop the risk metrics in NLWR. This presentation also highlighted the DRA activities we are involved, showcasing our contributions to global safety practices in NLWR.
Participation in the Meeting Nominated:
78 participants from 33 Member States and 1 Intl Org. Not all nominates were able to join
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Participated:
56 participants from 25 Member States and 1 Intl Org; plus +18 local participants (5 of which from the local hosting company NRG); Virtually 8%, in-person 92%
Different Stakeholders:
Regulators, industry, operators, research, academia, etc.
IAEA participation:
Safety Assessment Section, Research Reactor Safety Section
Meeting Agenda:
Opening session: Background information on IAEA activities on PSA and nuclear fuel cycle facilities safety 35 presentations on different perspectives: regulatory, industry, research and development, academia Working group discussion session on PSA assessment for non-reactor nuclear facilities:
Technical tour to 5 non-reactor facilities (NRG)
Observations Learned from the Meeting:
Difference between reactor and non-reactor facilities (i.e., important from PSA standpoint)
Overall process resulted from event of non -reactor facilities: Hazard Identification Scenario determination and analysis Likelihood estimation and Consequence analysis Analysis results Calculations and Actions.
Bounding assessments are frequently used, especially for low risk or low risk facilities. It seems okay for offsite release analysis and criteria, but it is not enough for internal needs e.g., optimization of procedures, design, modifications Regulatory frameworks not always include a requirement for a PSA for non-reactor facilities Cost factor is important factor in weather PSA is needed Chemical risk needs to be analyzed for NRF, non-radiological QRAs seems to be beneficial Completeness of hazard identification and scenario list is a key; IAEA SSG-3 guidance is applicable Dynamic modeling: can bring a lot of insights, especially for dynamic processes, e.g.,
recovery potential Uncertainties are also challenges Human interactions require detailed analysis and root cause identification for proper feedback from the risk assessment to improve safety of the facility Long term windows: due to slow development of events result in increased potential for recovery and repair actions Reliability data: some are applicable from NPP sources, need for improvement of OpEx sharing for NFCFs
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Communication of risk analysis results: Might be challenge, perhaps require thinking about the way to communicate also benefits not only adverse consequences Disposal facilities (thousands of years mission time) : perhaps focus on primary risks coming from near-term events, e.g., extreme hazar ds less relevant or distant future event
Discussion sessions w/ 5 working groups
5 topics were selected for working group discussions:
- 1. Whether PSA is needed for a given facility? What are the arguments?
- 3. Are there any regulatory requirements of PSA for NRF?
- 4. Potential PSA applications for different facilities?
- 5. What kind of risk metrices could be used for the different type of NRF?
Benefits of PSA, regulatory perspectives, risk metrics, etc.
Short time discussion, not a consensus, but interesting insights
Results Achieved:
All the main objectives of the meeting have been achieved.
Discussions on different methodologies and insights from PSA for non-reactor facilities Exploring the specific challenges and opport unities for PSA considering the differences between non-reactor facilities and NPP Learning about available experiences and ideas on how to use PSA for non-reactor nuclear facilities Input to IAEA: path forward and tailoring IAEA activities in this area
Pending Actions, Next Steps, and Commitments:
Some takeaways
Experience is available on use of PSA approaches for NRF Information exchange in this area needs to be intensified Guidance/Examples on NRF PSA are needed?
Need for harmonization of regulatory requirements?
Dynamic modeling is beneficial, but is resource intensive, so there is a need to understand when it is worth to apply
On the Margins:
None
Attachments ML:
Yes
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