ML22033A002
| ML22033A002 | |
| Person / Time | |
|---|---|
| Issue date: | 02/23/2022 |
| From: | Louise Lund Office of Nuclear Regulatory Research |
| To: | Shana Helton Office of Nuclear Material Safety and Safeguards |
| Matt Gordon | |
| Shared Package | |
| ML22033A001 | List: |
| References | |
| Download: ML22033A002 (3) | |
Text
February 23, 2022 MEMORANDUM TO: Shana Helton, Director Division of Fuel Management Office of Nuclear Material Safety and Safeguards Signed by Lund, Louise FROM: Louise Lund, Director on 02/23/22 Division of Engineering Office of Nuclear Regulatory Research
SUBJECT:
IMPENDING PUBLICATION OF TECHNICAL LETTER REPORT The Office of Nuclear Regulatory Research (RES) completed Technical Letter Report (TLR),
PNNL-32455, PNNL-Recommended CISCC Growth Rate Evaluation Test Plan for the NRC -
Update #1," provided by the Pacific Northwest National Laboratory (PNNL) (Agencywide Documents Access and Management System (ADAMS) Accession No. ML22033A003).
The technical information enclosed in this TLR presents an updated approach to a quantitative assessment of chloride-induced stress corrosion crack (CISCC) growth behavior of dry cask storage system stainless steel (SS) canisters. While testing is ongoing, key observations from recent test results under this program include the following:
316L exhibits substantially lower CISCC growth rates than 304L. A similar trend is also evident in the literature, and the literature also indicates that the threshold stress intensity for the onset of CISCC growth (Kth) is higher for 316/316L SS than for 304/304L SS.
Low amounts of cold work (CW) have little effect on the CISCC growth rate. However, literature data indicate that CW greatly reduces Kth, which is an important factor in the onset of CISCC.
Preliminary tests indicate that sodium nitrate is an effective inhibitor to CISCC growth of 304L SS in sodium chloride solutions.
Staff from the Division of Fuel Management in the Office of Nuclear Material Safety and Safeguards reviewed drafts of the TLR, and the enclosed final TLR reflect the resolution of their comments.
Please feel free to notify the responsible RES contact if you have any questions concerning the impending public release of this TLR. RES established an online quality survey to collect feedback from user offices on the usefulness of RES products and services. This survey can be CONTACT: Matthew Gordon, RES/DE/MEB (301) 452-9471
S. Helton found online at the RES Quality Survey. I would appreciate the responsible manager or supervisor completing this shortabout 5 minutessurvey within the next 30 calendar days to present your offices views of the delivered RES product.
If additional information is required, please contact Matthew Gordon of my staff at 301-452-9471 or mxg9@nrc.gov
Enclosure:
PNNL-32455, PNNL-Recommended CISCC Growth Rate Evaluation Test Plan for the NRC - Update #1
ML22033A001; ML22033A002 OFFICE RES/DE/CIB RES/DE/CMB RES/DE NAME MGordon MG EFocht EF LLund LL DATE Feb 2, 2022 Feb 18, 2022 Feb 23, 2022