ML25329A300
| ML25329A300 | |
| Person / Time | |
|---|---|
| Issue date: | 12/16/2025 |
| From: | Haimanot Yilma Storage and Transportation Licensing Branch |
| To: | Roman C Division of Fuel Management |
| References | |
| Download: ML25329A300 (0) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 MEMORANDUM TO:
Cinthya Román, Deputy Director Division of Fuel Management Office of Nuclear Material Safety and Safeguards FROM:
Haimanot Yilma, Sr. Project Manager Storage and Transportation Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards
SUBJECT:
SUMMARY
OF SEPTEMBER 10, 2025, MEETING RELATED TO HI-STAR 330 ACCEPTANCE REVIEW AUDIT
Background:
On September 10, 2025, a closed meeting was held to discuss the HI-STAR 330 Acceptance Review Audit, focusing on the transportation package designed for non-fuel waste, including reactor waste and hardware. The HI-STAR 330 application was submitted on March 10, 2025, with several issues identified during the review. Observations and requests for supplemental information were issued on August 1, 2025, and September 5, 2025, respectively.
Discussion:
The U.S. Nuclear Regulatory Commission (NRC) staff and representatives from Holtec International (Holtec) convened to address these issues and facilitate open and candid communication between the NRC staff and Holtec to ensure a thorough and efficient review process, ultimately ensuring the safety and regulatory compliance of the HI-STAR 330 package.
The primary objectives of the meeting were:
1.
Clarify Regulatory Requirements: Ensure that Holtec fully understands the NRC staff's regulatory needs and the specific issues raised in the observations and requests for supplemental information submitted.
2.
Discuss Technical Concerns: Address the NRC staff's questions about the robustness and accuracy of the modeling techniques used for the HI-STAR 330 package, particularly regarding impact scenarios, puncture tests, and material erosion.
CONTACT:
Haimanot Yilma, NMSS/DFM 301-415-5286 December 16, 2025 Signed by Yilma, Haimanot on 12/16/25
C. Román 2
3.
Plan for Additional Analysis: Agree on the need for further simulations and analyses to address the identified issues and ensure the package's safety and compliance with regulatory standards.
4.
Determine Next Steps: Establish a clear path forward, including timelines for Holtec to provide the necessary information and responses, and discuss potential options if the current deadlines are not attainable.
The meeting focused on discussing the type of analysis Holtec would need to do to confirm or demonstrate that HI-STAR 330 package design can withstand various impact and puncture scenarios.
Technical concerns discussed during the meeting include:
Impact Limiter Brackets: The staff pointed out that the modeling assumptions might not accurately reflect real-world conditions, particularly in terms of how the brackets would behave under impact. The analysis should demonstrate that the brackets will survive the corresponding impact scenarios to avoid potential breaches in the package.
Puncture and Fire Scenarios: The NRC staff emphasized the need for more detailed analysis of puncture scenarios, especially following a drop. The staff highlighted that the current models might not adequately account for the potential for breaches and the subsequent impact on containment and radiological safety.
Modeling Techniques: There were questions about the modeling techniques used, particularly the assumptions made about the impact limiter brackets and their connections. The NRC staff noted that the brackets were modeled as being more robust than they might be, which could lead to an underestimation of the risk of failure.
Secondary Impacts: The NRC staff highlighted the importance of considering secondary impacts and the cumulative effects of multiple impacts on the package's integrity as the current models might not fully account for these factors, potentially leading to an incomplete assessment of the package's safety.
Material Erosion and Triaxiality: There were discussions related to erosion of materials and the need to consider triaxiality effects in the modeling. The NRC staff pointed out that certain areas of the package might experience erosion under stress, and this needed to be accurately modeled to ensure the package's integrity.
Bolts and Connections: The NRC staff noted that the structural evaluation of bolts and connections, particularly those on the corners of the package, was not adequately addressed. They emphasized the need for a more detailed analysis of these components to ensure they could withstand the stresses they would encounter during impact scenarios.
Gap Sizes and Tolerances: There was a discussion about the gap sizes and tolerances between different components of the package. The NRC staff stressed the importance of accurately modeling these gaps to ensure that the package's structural integrity was maintained under various conditions.
C. Román 3
Holtec representatives explained the current modeling techniques and the rationale behind their design choices. They acknowledged the NRC staff's information needs and agreed to perform additional simulations and analyses to address these issues. Holtec emphasized that their current models were conservative and designed to ensure the highest level of safety. The discussion included technical details about the materials used, the structural integrity of various components, and the potential need for design modifications to enhance safety.
Next Steps:
1.
Additional Simulations and Analyses: Holtec will conduct further simulations and analyses to address the NRC staff's concerns, particularly regarding the impact limiter brackets and potential puncture scenarios.
2.
Documentation and Clarification: Holtec will provide detailed documentation and clarification on their modeling techniques, design choices, and the rationale behind them. This will include addressing the secondary impacts and cumulative effects of multiple impacts.
3.
Response Submission: Holtec committed to performing additional analyses and providing detailed responses to the observations raised.
4.
Follow-Up Discussions: If needed, further discussions and clarifications will be scheduled to ensure all concerns are thoroughly addressed. This may involve additional meetings or calls to resolve any outstanding issues.
5.
Regulatory Review: The NRC staff will review Holtec's submissions once received.
Depending on the quality and completeness of the responses, the staff will decide on the next steps, which could include extending the review period, requesting further information, or other regulatory actions.
These steps aim to ensure that the HI-STAR 330 package meets all safety and regulatory requirements, providing a robust and reliable solution for the transportation of non-fuel waste.
The meeting was productive, with both the NRC staff and Holtec agreeing on the need for further analysis and clarification. The NRC staff reiterated the importance of high-quality responses and thorough documentation to meet regulatory requirements and ensure public safety. Holtec committed to addressing the identified issues and providing the necessary information. As of December 2, 2025, the responses to the RSIs and observations were submitted. The meeting underscored the collaborative effort required to achieve a safe and effective transportation package for non-fuel waste, highlighting the importance of clear communication and rigorous technical evaluation.
Enclosure:
- 1. Meeting Attendees
ML25329A300 OFFICE NMSS/DFM NMSS/DFM NMSS/DFM NMSS/DFM NMSS/DFM NAME HYilma SFigueroa YDiaz-Sanabria CRomán HYilma DATE 11/26/2025 12/02/2025 12/03/2025 12/11/2025 12/16/2025
Enclosure Meeting Attendees List
SUMMARY
OF SEPTEMBER 10, 2025, MEETING RELATED TO HI-STAR 330 ACCEPTANCE REVIEW AUDIT The U.S. Nuclear Regulatory Commission Shana Helton Yoira Diaz Sanabria Lisa Regner Gerond George Jason Piotter Janine Smith Gang Zhao Nishka Devaser Rigato, Antonio B (PNNL)
Haimanot Yilma Holtec International Kimberly Manzione Ali Elzahri Robert Mahorter Venkat Prabhala Artem Stavenko Chuck Bullard Abrar Mohammad Raja Maheedhara Dhake, Nilesh Nikhil Padghan Justin Sledzinski Kenny Hickman