ML19319B313
| ML19319B313 | |
| Person / Time | |
|---|---|
| Issue date: | 11/13/2019 |
| From: | NRC/OCIO |
| To: | |
| Shared Package | |
| ML19319B303 | List: |
| References | |
| FOIA, NRC-2018-000831 | |
| Download: ML19319B313 (5) | |
Text
NRC Perspective on Harvesting Experience and Lessons Learned NRC Staff March 8, 2017
NRC Harvesting Experience RPV materials
- Shoreham, Midland Reactor vessel head CRDM penetrations
- North Anna, Davis-Besse Pressurizer from St. Lucie Piping from VC Summer, NMP, Oconee Reactor internals from Zorita
- Joint harvesting and testing project with EPRI and international Neutron absorbers from Zion
- Harvesting coordinated with DOE and EPRI; Independent NRC testing Concrete from Zorita Cables from Zion and Crystal River 2
Previous Benefits of Harvesting
- Reduce unnecessary conservatism
- Flaw distributions and Master Curve information came from harvested materials to support PTS rule
- Understand in-service flaws
- Mockups for NDE qualification
- Leak rate methodology from studying in-service flaws
- Identify and better understand safety issues
- High-energy arc fault tests on aluminum electrical components 3
Technical Lessons Learned
- Harvesting can provide highly representative aged materials for research
- May be only practical source of representative aged materials, particularly if irradiation and temperature are important factors
- Achieving high fluence levels with representative irradiation conditions through other means is very challenging
- May be able to use limited harvested materials to validate larger accelerated aging data set
- Important to gain as much information as possible in advance before committing to specific harvesting project
- Ideally a bounding, yet realistic, material/environment
- Understand material information (CMTRs if available) and plant operating conditions 4
Logistical Lessons Learned
- Harvesting is an expensive, time-consuming effort
- Must balance cost with potential benefits carefully
- High technical relevance of materials is needed to ensure value
- Leveraging resources with other research organizations helps mitigate cost challenges
- Can introduce challenges for testing when aligning research priorities and interests of multiple organizations
- May be needed, particularly for expensive testing of irradiated materials
- Transporting irradiated materials, particularly internationally, is cumbersome and time-consuming
- Avoiding extra transport, especially between countries, is highly recommended 5