ML25119A220
| ML25119A220 | |
| Person / Time | |
|---|---|
| Site: | 07109270 |
| Issue date: | 05/28/2025 |
| From: | Nishka Devaser Storage and Transportation Licensing Branch |
| To: | Baldner H NAC International |
| References | |
| EPID L-2025-LLA-0005 | |
| Download: ML25119A220 (1) | |
Text
Heath Baldner, Licensing Manager NAC International 3930 East Jones Bridge Road, Suite 200 Norcross, GA 30092
SUBJECT:
REVISION 7 OF CERTIFICATE OF COMPLIANCE NO. 9270 FOR THE MODEL NO. UMS TRANSPORT PACKAGE - REQUEST FOR ADDITIONAL INFORMATION
Dear Heath Baldner:
By application dated December 20, 2024 (Agencywide Documents Access and Management System [ADAMS] Accession No. ML24355A160), NAC International applied for amendment to Certificate of Compliance No. 9270 for the Model No. UMS Transport package.
In connection with our review, the U.S. Nuclear Regulatory Commission (NRC) needs the information identified in the enclosure to this letter. Additional information requested by this letter should be submitted in the form of revised pages. Please provide your response within 30 days from the date of this letter.
In accordance with Title 10 of the Code of Federal Regulations Section 2.390, Public inspections, exemptions, requests for withholding, a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records component of the NRCs ADAMS. ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. The PDR is open by appointment.
To make an appointment to visit the PDR, please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m. eastern time (ET), Monday through Friday, except Federal holidays.
May 28, 2025
H. Baldner 2
Please reference Docket No. 71-9270 and Enterprise Project Identifier No. L-2025-LLA-0005 in future correspondence related to this request. The staff is available to meet to discuss your proposed responses. If you have any questions, I may be contacted at 301-415-5196.
Sincerely, Nishka Devaser, Project Manager Storage and Transportation Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards Docket No. 71-9270 EPID L-2025-LLA-0005
Enclosure:
- 1. Request for Additional Information Signed by Devaser, Nishka on 05/28/25
- ML25119A220 OFFICE NMSS/DFM NMSS/DFM NMSS/DFM NAME NDevaser SFigueroa JSmith DATE 04/29/25 04/30/25 05/1/25 OFFICE NMSS/DFM NMSS/DFM NMSS/DFM NAME DDunn LRegner YDiaz-Sanabria DATE 05/5/25 05/8/25 05/27/25 OFFICE NMSS/DFM NAME NDevaser DATE 05/28/25
Enclosure Request for Additional Information Docket No. 71-9270 Model No. UMS Transport Package Certificate of Compliance No. 9270 Revision No. 7 By application dated December 20, 2024 (Agencywide Documents Access and Management System Accession No. ML24355A160), NAC International (NAC) submitted an application for amendment to Certificate of Compliance (CoC) No. 9270 for the Model No. UMS Transport package. This request for additional information identifies information needed by the U.S. Nuclear Regulatory Commission staff (the staff) in connection with its review of the application. The staff used guidance provided in NUREG-2216, "Standard Review Plan for Transportation Packages for Spent Fuel and Radioactive Material, in its review of the application.
The questions below describe information needed by the staff for it to complete its review of the application and to determine whether the applicant has demonstrated compliance with regulatory requirements.
Structural and Materials Analysis RAI 1.
Provide yield stress values for the M5 cladding alloy at 400 degrees Celsius (°C) to support the analysis in NAC calculation EA790-2524, Revision 0, Fuel Rod Evaluation for the UMS Transport Cask 30-ft Side Drop Accident. Table 1.0-1 of the calculation lists the yield stress of pressurized-water reactor M5 cladding at 400°C as 68.2 kilopound-force per square inch (ksi) (470 Mpa). Per section 4.0 of the calculation, the reference for this yield strength value is the ZrNb-1a entry of table 5 of Bourdiliau, B, et al., "Impact of Irradiation Damage Recovery During Transportation of the Subsequent Room Temperature Tensile Behavior of Irradiated Zirconium Alloys," JAI Vol. 7, No. 9. Section 5.0 of the calculation states that this yield strength value does not consider any strain rate effects.
The staff notes that table 5 of the Bourdiliau publication lists values for Zr-1%Nb specimens whose tensile properties were determined at room temperature; whereas the ZrNb-1a entry associated with the 470 MPa (68.2 ksi) yield stress value had been subjected to over 3000 hours0.0347 days <br />0.833 hours <br />0.00496 weeks <br />0.00114 months <br /> of 400°C temperature exposure prior to the determination of the published properties. The lower yield stress for this sample, compared to the yield strength of the as irradiated material, is a result of the annealing of irradiation damage during the creep testing conducted at 400°C.
The applicant is requested to provide a valid yield stress for M5 cladding at 400°C and revise calculation EA790-2524, as necessary to verify that the yield stress value for the M5 cladding is not exceeded for the 30-feet (ft.) side drop accident analysis and make any necessary adjustments to the summary in the safety analysis report section 2.11.4.
This information is required to satisfy the requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 71.55(e) and 71.73(c)(1).
2 RAI 2.
In section 1.0 of NAC calculation EA790-2524, Revision 0, explain why the cladding-only properties are not increased by a factor of 1.25 for this particular analysis, when they have been for the MAGNATRAN 30-ft. drop analysis.
It appears to staff that, since in section 6.4 of the calculation, the resulting frequencies and effective accelerations of the fuel rods appear to be rather high relative to the corresponding cask accelerations, inclusion of the 1.25 factor would further increase the frequency response of the fuel rods, which may further increase the resulting dynamic load factor (DLF). The applicant is asked to verify that the determination was made that excluding the 1.25 factor in the frequency analysis of each fuel rod produced the bounding DLF results, as presented in section 6.4.
This information is required to satisfy the requirements of 10 CFR Part 71.55(e) and 71.73(c)(1).