ML26030A201
| ML26030A201 | |
| Person / Time | |
|---|---|
| Site: | 07109337 |
| Issue date: | 02/25/2026 |
| From: | Storage and Transportation Licensing Branch |
| To: | |
| References | |
| EPID L-2026-RNW-0001, EPID L-2026-LLA-0023 | |
| Download: ML26030A201 (0) | |
Text
Enclosure 2 SAFETY EVALUATION REPORT Docket No. 71-9337 Safkeg-LS Model No. 3979A Package Certificate of Compliance No. 9337 Revision No. 6
SUMMARY
By application dated December 12, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25350A015), Croft Associates Limited (Croft) requested renewal, without changes, of Certificate of Compliance (CoC) No. 9337 for the Safkeg-LS Model No. 3979A package. Subsequently, by letter dated February 3, 2026 (ML26034B901), Croft submitted an application for amendment to CoC No. 9337 to include an allowance for activation impurities for all solid content types listed in the CoC. The February 3, 2026, letter requested the CoC amendment to be included in the CoC renewal by the end of February 2026, or if not possible, at the earliest possible date after the renewal.
The certificate has been renewed for a five-year term and amended to include an allowance for activation impurities.
The U.S. Nuclear Regulatory Commission (NRC) staff reviewed the application using the guidance in NUREG-2216, Standard Review Plan for Transportation Packages for Spent Fuel and Radioactive Material (ML20234A651). Based on the statements and representations in the application, as supplemented, and the conditions listed in the CoC, the staff concludes that the package meets the requirements in Title 10 of the Code of Federal Regulations (10 CFR)
Part 71.
EVALUATION The proposed amendment would allow small quantities of additional radionuclides not previously considered in the original analysis. These additional radionuclides are activation products generated in a reactor as a result of impurities or contaminants in the ampules or the contained product.
Croft submitted bounding inventories of these additional radionuclides (i.e., bounding list of contaminants / impurities) from two current users of the package, summarized in tables 1 and 2 of the February 3, 2026, amendment request. Many of these additional radionuclides have short half-lives; however, delaying shipment until they decay below exempt activity limits would reduce the available medical product. To address this, Croft requested:
Inclusion of an allowance for a defined A2 quantity (i.e., up to 0.25 x A2) of radionuclides not listed within the CoC that arise due to impurities of the contents.
A requirement that any radionuclides not listed in the CoC continue to meet the other contents requirements, package heat and dose limits, and specified mass limits in the CoC.
2 The NRC staff reviewed the radionuclides listed in tables 1 and 2 of the February 3, 2026, amendment request. Collectively, these tables identify a total of 36 radionuclides (34 unique radionuclides between the 2 tables). The combined activity of all 36 radionuclides identified by both users is less than 0.18 terabecquerel (TBq) (4.87 curie (Ci)), which represents only a small fraction of the hypothetical 37 TBq (1000 Ci) Ir-192 point source used to evaluate the package shielding.1 Croft also estimated, and the NRC staff confirmed that the total additional activity in the package from the bounding list of contaminants / impurities from either user would be about 0.22 x A2.
Source Term The hypothetical source term for CoC No. 9337 is 37 TBq (1,000 Ci) of Ir-192 (ML110250364).
Dose rates for this source term were confirmed to meet 10 CFR Part 71 limits as evaluated by Croft and confirmed by NRC staff. Adding 0.18 TBq does not significantly increase dose rates, which remain compliant with regulatory requirements.
Activation products or contamination from impurities contribute to only a minimal increase in radiation. The Safkeg-LS shielding features continue to provide adequate protection. Therefore, NRC staff supports adding an allowance for these impurities in the CoC.
Thermal and Containment Additionally, using heat generation values for all 34 unique radionuclides, Croft estimated the maximum additional decay heat from a bounding list of contaminants / impurities from either user would be less than 1.1 x 10-2 watts, which is a small fraction of the 10 watt decay heat authorized for this package. The containment boundary acceptance criteria is leaktight (1 x 10-7 ref-cm3/s) per the American National Standards Institute (ANSI) N14.52, as described in sections 4.2.2 and 4.3.2 of the safety analysis report3; therefore, because there are no containment leakage rate calculations based on the content radionuclides, an additional 0.22 x A2 does not impact the containment results. The 0.22 x A2 quantity is also bound by the applicant requested 0.25 x A2 quantity of impurities that are not listed in the CoC. The applicant also confirmed that the impurities are solid or are absorbed into the solid contents or aluminum capsule; therefore, there is no gas generation from the impurities to increase the internal pressure.
On the basis that activation products resulting from impurities or contaminants appear to pose very small additional sources of radiation and decay heat, the NRC staff agrees that an allowance for these impurities may be provided in the CoC.
CONDITIONS The CoC includes the following conditions of approval:
1 Letter to R. Vaughn, Croft, from R. Johnson, NRC dated January 24, 2011, Re: Original Issue of Certificate of Compliance No. 9337, ADAMS Package Accession No. ML110250350.
2 ANSI N14.5, American National Standard for Radioactive Materials - Leakage Tests on Packages for Shipment, American National Standards Institute, 2022.
3 CTR 2008/10, Revision 4, Safety Analysis Report for Packaging Safkeg-LS Design No. 3979A, dated September 2012, ADAMS Accession No. ML12250A456.
3 Condition No. 5.(b)(2) Maximum quantity of material per package was revised to include an allowance of 0.25 x A2 quantity for activation products not listed in the CoC, provided all other requirements in the certificate are met.
Condition No. 9 was revised to authorize use of the previous revision of the certificate, Revision No. 5, until April 30, 2026.
Condition No. 10 was updated to reflect the new expiration date of April 30, 2031.
The References were updated to include the February 3, 2026, application for the amendment.
CONCLUSION The certificate has been renewed for a five-year term, which expires on April 30, 2031. Based on the statements contained in the applications, and the conditions listed above, the staff concludes that the changes indicated do not affect the ability of the package to meet the requirements of 10 CFR Part 71.
Issued with Certificate of Compliance No. 9337, Revision No. 6.