ML24082A130
| ML24082A130 | |
| Person / Time | |
|---|---|
| Site: | 07201031, 07201015, 07201025, 07109235 |
| Issue date: | 04/18/2024 |
| From: | Shana Helton NRC/NMSS/DFM/IOB |
| To: | Cole K NAC International |
| References | |
| EA-23-069 IR 2023201 | |
| Download: ML24082A130 (1) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 EA-23-069 Kent Cole, President and Chief Executive Officer NAC International, Incorporated 2 Sun Court, Suite 220 Peachtree Corners, GA 30092
SUBJECT:
NAC INTERNATIONAL, INC. - NOTICE OF VIOLATION; U.S. NUCLEAR REGULATORY COMMISSION INSPECTION REPORT 72-01031/2023-201
Dear Kent Cole:
This letter refers to the U.S. Nuclear Regulatory Commission (NRC) announced inspection conducted from March 20-23, 2023, at your NAC International Incorporated (NAC) corporate office in Norcross, Georgia. The purpose of the inspection was to assess the adequacy of NACs design activities for spent fuel storage casks regarding the applicable requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 72, Licensing Requirements for the Independent Storage of Spent Nuclear Fuel, High-level Radioactive Waste, and Reactor-related Greater Than Class C Waste.
Based on the information developed during the inspection, the NRC identified two apparent violations. The NRC provided details of the inspection in NRC Inspection Report 07201031/2023-201, dated December 7, 2023. The inspection report can be found in the NRCs Agencywide Documents Access and Management System (ADAMS) at Accession No. ML23283A238. ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html.
In the letter transmitting the inspection report, we provided you with the opportunity to address the two apparent violations identified in the report by either: (1) submitting a written response; (2) attending a Pre-decisional Enforcement Conference (PEC), or (3) participating in an Alternative Dispute Resolution session before we made our final enforcement decision. In a letter dated January 8, 2024 (ML24008A248), you provided your response to the apparent violations.
Based on the information developed during the inspection and the information you provided in your written response to the inspection report, the NRC determined that two violations of NRC requirements occurred. These violations are cited in the Enclosure, Notice of Violation (Notice), and the circumstances surrounding them are described in detail in the subject inspection report. The violations involved the following: (A) the failure to establish adequate design control measures for a design calculation; and (B) the failure to submit a written report to the NRC within 30 days of discovery of a design deficiency.
April 18, 2024
K. Cole The NRC considers the failures to establish adequate design control measures for verifying or checking the adequacy of design, and to submit a written report to the NRC within 30 days of discovery of a design deficiency, to be violations that are of more than minor concern. The NRC staff dispositioned the violations as Severity Level IV in accordance with the NRC Enforcement Policy and Manual. Although the non-cited violation criteria in Section 2.3.2 of the Enforcement Policy are met for both violations, they are being cited in the Notice because the violations are associated with a system designed to mitigate a serious safety event that did not meet design specifications. The NRC Enforcement Policy can be found on the NRCs website at http://www.nrc.gov/about-nrc/regulatory/enforcement/enforce-pol.html.
The potential consequence of NACs failure to establish adequate design control measures for verifying or checking the adequacy of the design calculation was a cask tip-over event resulting in damaged fuel assemblies. Based on the written response, the NRC noted that NAC revised the calculations referenced in the final safety analysis to demonstrate that the important to safety components, including the fuel rods, would not rupture during the bounding design basis tip-over accident, as the cladding would maintain its integrity that had a safety margin greater than one. The team concluded that there was no immediate or current safety issue for the storage systems on the ISFSI pad or during handling operations when considering the additional information provided in the written response and discussions with engineering personnel.
The NRC staff determined that the potential safety significance for Violation A was very low and revised the apparent violation to reflect the NRCs conclusion. Therefore, the NRC assigned a significance of Severity Level IV (i.e., violations that are less serious, but are of more than minor concern) because the violation involved the failure to meet regulatory requirements, including one or more quality assurance criteria of design control that have more than minor safety significance (see section 6.5.d.1 of the Enforcement Policy). The NRC staff also revised Violation B and assigned a significance of Severity Level IV because NAC failed to make a required report that, had it been submitted, would have resulted in the NRC increasing the inspection scope of the next regularly scheduled inspection (see section 6.9.d.1 of the Enforcement Policy), as this potentially impacted the NRCs ability to perform its regulatory function. The NRC also included the date of when NAC needed to submit the required report and revised the Notice to reflect this information.
In addition, in your written response, you requested that the NRC staff amend the language in Violation A to avoid giving the impression that there has been a longstanding deficiency (i.e.
from 2007 to 2023) in your design control program. Accordingly, the enclosed Notice includes language to clarify that NAC failed to identify a calculation error in 2007, which was subsequently propagated into two other calculations in 2019 and 2020.
The NRC has concluded that information regarding: (1) the reason for the violations; (2) the corrective actions that have been taken and the results achieved; and (3) the date when full compliance was achieved is already adequately addressed on the docket in Inspection Report 072-01031/2023-201 and in your letter dated January 8, 2024. Therefore, you are not required to respond to this letter unless the description therein does not accurately reflect your corrective actions or your position. In that case, or if you choose to provide additional information, you should follow the instructions specified in the enclosed Notice.
K. Cole In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter, its enclosure, and your response, if any, will be made available electronically for public inspection in the NRC Public Document Room and in ADAMS, accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the Public without redaction. If personal privacy or proprietary information is necessary to provide an acceptable response, please provide a bracketed copy of your response that identifies the information that should be protected and a redacted copy of your response that deletes such information. If you request withholding of such information, you must specifically identify the portions of your response that you seek to have withheld and provide in detail the bases for your claim of withholding (e.g., explain why the disclosure of information will create an unwarranted invasion of personal privacy or provide the information required by 10 CFR 2.390(b) to support a request for withholding confidential commercial or financial information).
If you have any questions concerning this matter, please contact Hector Rodriguez at (301) 415-6004 or email Hector.Rodriguez-Luccioni@nrc.gov.
Sincerely, Shana Helton, Director Division of Fuel Management Office of Nuclear Material Safety and Safeguards Docket No. 72-1031
Enclosure:
Notice of Violation Signed by Helton, Shana on 04/18/24
ML24082A130 OFFICE NMSS/DFM NMSS/DFM/LA NMSS/DFM/BC NMSS/MSST/PM NMSS/DFM NAME MDavis WWheatley HRodriguez ARoberts LHowell DATE 03/26/24 03/27/24 04/08/24 04/04/24 04/04/24 OFFICE OE OGC NMSS/DFM/D NAME DJones RCarpenter SHelton DATE 04/08/2024 04/16/2024 04/18/2024
Enclosure NOTICE OF VIOLATION NAC International Docket No. 72-1031 Peachtree Corners, GA EA-23-069 During a U.S. Nuclear Regulatory Commission (NRC) inspection, conducted from March 20-23, 2023, at the NAC International Incorporated (NAC) corporate office in Norcross, Georgia, the NRC identified two violations of NRC requirements. In accordance with the NRC Enforcement Policy, the violations are listed below:
Violation A:
10 CFR 72.146(b), Design Control, requires, in part, that design control measures must provide for verifying or checking the adequacy of design by methods such as design reviews, alternate or simplified calculational methods, or by a suitable testing program.
Contrary to the above, from September 2007 through March 2023, NAC failed to establish adequate design control measures for verifying or checking the adequacy of design by methods such as design reviews or simplified calculational methods.
Specifically, NAC failed to identify a calculation error in 2007, which was subsequently propagated into two other calculations in 2019 and 2020. NAC failed to provide design control measures for adequately verifying input parameters to a finite element analysis used in a fuel rod structural calculation for two storage systems (i.e., NAC-UMS, MAGNASTOR) and two transportation systems (i.e., NAC-STC, and MAGNATRAN). For example, NAC used a value of 0.215 inches for one of the fuel rod diameters in their computational model calculation 71160-2025 when the value should have been 0.431 inches. This error resulted in the stress demands on the fuel rod being reported as half of its value and once corrected the system exceeded the design basis limits having a safety margin of less than one. This indicated that the stresses induced on the fuel rod cladding would exceed the yield stress of the cladding.
This is a Severity Level IV violation (NRC Enforcement Policy, section 6.5.d.1)
Violation B:
10 CFR 72.242, Record Keeping and Reports, requires, in part, that each certificate holder shall submit a written report to the NRC within 30 days of discovery of a design or fabrication deficiency, for any spent fuel storage cask which has been delivered to a licensee, when the design or fabrication deficiency affects the ability of structures, systems, and components important to safety to perform their intended safety function.
Contrary to the above, from April 27, 2022, to March 11, 2023, NAC failed to submit a written report to the NRC within 30 days of discovery of a design or fabrication deficiency, for any spent fuel storage cask which has been delivered to a licensee, when the design or fabrication deficiency affects the ability of structures, systems, and components important to safety to perform their intended safety function. Specifically, NAC failed to submit a written report to the NRC within 30 days of discovery (i.e., by April 27, 2022), of a design error in a fuel rod structural calculation that impacted the NAC-UMS and MAGNASTOR storage systems which had been delivered to general licensees (i.e., Palo Verde, McGuire, Catawba, Zion, Kewaunee, and Three Mile Island) when the design deficiency exceeded design limits. NAC discovered this design deficiency in calculation 71160-2025 on March 29, 2022, that adversely impacted the computation for bending stresses (i.e., negative margins) for spent fuel rods. Eventually, NAC submitted the required report to the NRC on March 11, 2023, and updated the report on March 28, 2023 (ML23087A062); this was approximately 11 months after NAC identified the issue.
This is a Severity Level IV violation (NRC Enforcement Policy, section 6.9.d.1)
The NRC has concluded that information regarding: (1) the reason for the violations; (2) the corrective actions that have been taken and the results achieved; and (3) the date when full compliance would be achieved is already adequately addressed on the docket in NACs written response to the Inspection Report in your letter dated January 8, 2024 (ML24008A248).
However, you are required to submit a written statement or explanation pursuant to 10 CFR 2.201 if the description therein does not accurately reflect your corrective actions or your position. In that case, or if you choose to respond, clearly mark your response as a Reply to a Notice of Violation, EA-23-069, and send it to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001 with a copy to Shana Helton, Division Director, Division of Fuel Management, Office of Nuclear Material Safety and Safeguards, Two White Flint North, 11545 Rockville Pike, Rockville, MD 20852-2738, within 30 days of the date of the letter transmitting this Notice of Violation (Notice).
If you contest this enforcement action, you should also provide a copy of your response, with the basis for your denial, to the Director, Office of Enforcement, United States Nuclear Regulatory Commission, Washington, DC 20555-0001.
If you choose to respond, your response will be made available electronically for public inspection in the NRC Public Document Room or in the NRCs Agencywide Documents Access and Management System, accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. Therefore, to the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the public without redaction.
If personal privacy or proprietary information is necessary to provide an acceptable response, then please provide a bracketed copy of your response that identifies the information that should be protected and a redacted copy of your response that deletes such information. If you request withholding of such material, you must specifically identify the portions of your response that you seek to have withheld and provide in detail the bases for your claim of withholding (e.g.,
explain why the disclosure of information will create an unwarranted invasion of personal privacy or provide the information required by 10 CFR 2.390(b) to support a request for withholding confidential commercial or financial information). If safeguards information is necessary to provide an acceptable response, please provide the level of protection described in 10 CFR 73.21. If Classified Information is necessary to provide an acceptable response, please provide the level of protection described in 10 CFR Part 95.
In accordance with 10 CFR 19.11, you may be required to post this Notice within two working days of receipt.
Dated this 18th day of April 2024