ML26040A328
| ML26040A328 | |
| Person / Time | |
|---|---|
| Site: | 07109225 |
| Issue date: | 02/09/2026 |
| From: | Baldner H NAC International |
| To: | Office of Nuclear Material Safety and Safeguards, Document Control Desk |
| References | |
| ED20260020 | |
| Download: ML26040A328 (0) | |
Text
ED20260020 Atlanta Corporate Headquarters 2 Sun Court, Suite 220 Peachtree Corners, GA 30092 Phone 770-447-1144 www.nacintl.com February 9, 2026 U.S. Nuclear Regulatory Commission Director, Division of Spent Fuel Management U.S. Nuclear Regulatory Commission 11555 Rockville Pike Rockville, MD 20852-2738 Attention:
Document Control Desk
Subject:
Submission of a Supplement to Responses to the Nuclear Regulatory Commission Request for Additional Information for the NAC International Request to Expand the LWT Cask WESF (Waste Encapsulation and Storage Facility) SrF2 Capsules Definition.
Docket 71-9225
References:
- 1.
USNRC CoC No. 9225, Revision 77, Model No. NAC-LWT Package, Dated July 14, 2025
- 2.
ED20250003, Submission of NAC-LWT Safety Analysis Report, Revision 49, Incorporating Fabrication Improvements to the TRIGA Fuel Basket, February 4, 2025
- 3.
ED20250066, Submission of a Request for a Revision to Certificate of Compliance (CoC) No. 9225 for the NAC-LWT Cask to Expand on the Definition of WESF (Waste Encapsulation and Storage Facility) SrF2 Capsules, July 7, 2025
- 4.
ED20250088, 10 CFR 71.95 Report for Instances Where the Conditions of Approval in the Certificate of Compliance Were Not Observed in Making a Shipment and a Request to Revision to Certificate of Compliance (CoC) No. 9255 for the NAC-LWT Cask, June 26, 2025
- 5.
US NRC Correspondence, Revision 78 of Certificate of Compliance No.
9225 For The Model No. NAC-LWT Package +/- Request for Additional Information, December 22, 2025
- 6.
ED20260003, Submission of Responses to the Nuclear Regulatory Commission Request for Additional Information for the NAC International Request to Expand the LWT Cask WESF (Waste Encapsulation and Storage Facility) SrF2 Capsules Definition, January 23, 2025
Nuclear Regulatory Commission February 9, 2026 Page 2 of 2 ED20260020 NAC International Inc. (NAC) hereby submits a supplement to our responses (Reference 6) to the NRC Request for Additional Information (RAI) issued on December 22, 2025 (Reference 5). of this submittal contains a replacement page for the Operational steps contained in Chapter 7 of the Safety Analysis Report. Specifically, Step 25 on page 7.1-101 was updated to clarify that the UCS Lid Spacer is required during transport of the UCS. This change is consistent with the changes previously provided with our RAI response on January 23, 2025.
This replacement page is common to both the proprietary and non-proprietary versions of the SAR.
If you have any questions regarding this letter, please feel free to contact me on my direct number at 678-328-1252.
Sincerely, Heath Baldner Director, Licensing Attachments: +/- Replacement SAR Changed Page, NAC-LWT SAR, Revision 26A
ED20260020 Replacement SAR Changed Page, NAC-LWT SAR, Revision 26A
NAC-LWT Cask SAR January 2026 Revision 26A NAC international 7.1-101
- 20.
Place the transfer cask containing the UCS or UCS spacer assembly onto the dry transfer system components positioned on the top of the cask.
- 21.
Lower the loaded UCS or UCS spacer assembly from the transfer cask into the basket within the NAC-LWT cask cavity.
- 22.
Remove the transfer cask from the dry transfer system adapter.
- 23.
Repeat steps 17 through 22 until a total of 3 UCSs, or 1 or more UCSs with up to 2 UCS spacer assemblies, are installed.
- 24.
Remove shield ring components, if required.
- 25.
Verify the UCS LWT lid spacer is bolted to the closure lid. Verify all lid spacer bolts are torqued to 200 +/- 20 in-lbs.
- 26.
Install the closure lid onto the cask. Visually verify that the lid is properly seated.
- 27.
Install lid bolts hand tight.
- 28.
Remove dry transfer system components from the top of the cask.
- 29.
Tighten all 12 closure lid bolts to 260 +/- 20 ft-lbs in three passes using the torque sequence indicated on the closure lid.
- 30.
Connect a helium gas supply line to the vent valve, a vent line to the drain valve, and purge helium into the cask cavity. Remove the vent line and gas supply line.
- 31.
Connect the Vacuum Drying System (VDS) to the cask vent valve and evacuate the cask cavity by vacuum pump to less than or equal to 10 torr (13 mbar) and continue vacuum pumping for a minimum of 15 minutes.
- 32.
At the end of the evacuation period, isolate the cask cavity from the vacuum pump and monitor the cask cavity pressure for a minimum of 10 minutes. If the pressure rise is less than 5 torr (6.7 mbar), the cavity is verified as dry of free water. If the pressure rise is greater than 5 torr (6.7 mbar), resume vacuum drying until the dryness verification results are satisfactory.
- 33.
Backfill the cask cavity with helium to 0 psig (+1, -0 psig) and disconnect the VDS from the vent valve.
- 34.
Perform a helium leakage test of the closure lid containment O-ring using a Helium Mass Spectrometer Leak Detector (MSLD) in accordance with the requirements of SAR Section 8.1.3.1.
- 35.
Install the vent and drain alternate port covers and torque the bolts to 100 +/-10 inch-pounds.
- 36.
If an alternate port cover containment O-ring seal was replaced, perform a helium leakage test on the affected port cover using a He MSLD in accordance with the requirements of SAR Section 8.1.3.2.2.
- 37.
If the alternate port cover containment seal was inspected and accepted for reuse, perform an air pressure drop leakage test on the affected port cover as follows.
- a.
Install a pressure test fixture to the port cover test port, including a calibrated pressure gauge with a minimum sensitivity of 0.25 psi.
- b.
Pressurize the port cover seal annulus to 15 psig, +1, -0 psi.
- c.
Isolate the gas supply and observe the pressure gauge for a minimum of 5 minutes.