ML23080A126
| ML23080A126 | |
| Person / Time | |
|---|---|
| Site: | 07109374 |
| Issue date: | 03/26/2023 |
| From: | Storage and Transportation Licensing Branch |
| To: | Holtec |
| Shared Package | |
| ML23080A124 | List: |
| References | |
| EPID L-2021-LLA-0130 | |
| Download: ML23080A126 (1) | |
Text
Enclosure Second Request for Additional Information Docket No. 71-9374 Model No. HI-STAR 80 Package By letter dated July 29, 2021 (Agencywide Documents Access and Management System
{ADAMS} Package Accession No. ML21210A403), Holtec International (Holtec) submitted an amendment request for the Model No. HI-STAR 80 package.
The amendment request includes the following: (i) addition of quivers to the allowable contents for both the F-12P and F-32B baskets (quivers are containers for storing separated spent fuel rods) with a maximum of 4 quivers to be loaded in the F-12P basket, and 12 quivers to be loaded in the F-32B basket, (ii) a maximum heat load of 43.5 kW to allows for spent fuel pools to be offloaded sooner after plant shutdown, (iii) a maximum PWR fuel assembly weight to 800 kg for loading in all basket cell locations, (iv) a Metamic-HT weld soundness criteria requiring only visual examination and bend testing, (v) a revision of the helium leakage rate acceptance criteria and test sensitivity for the containment enclosure leakage rate test, and (vi) the elimination of the requirement for bolting material to perform a volumetric examination of each bolt to ensure absence of voids.
On November 7, 2022, staff issued a first request for additional information (RAI) (ADAMS No.
ML22305A588). This second request for additional information identifies specific information for which the applicants responses (ADAMS No. ML22356A253) to the first round of RAIs were deemed inadequate.
Each individual RAI describes information needed by the staff to complete its review of the application and to determine whether the applicant has demonstrated compliance with the regulatory requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 71.
CHAPTER 2 STRUCTURAL AND MATERIALS REVIEW:
2-1 Provide the updated LS-DYNA model files for the 2.1% drop analyses.
The applicants response to the RAI 2-3, dated November 7, 2022, assumed that it was simply addressing the alphabetical listing of the d3plot file names on the SharePoint site.
Rather, the large set of downloadable files appears to contain result files from different analyses. For example, postprocessing of the results for the 2.1% oblique analysis from the SharePoint directory SD-B-one-fuel indicated d3plot files were inadvertently intermingled from multiple models. The time step jumps from 0.08s at State 161 to 0.0405s at State 162. Additionally, the file 1.d3plot74 was missing from the SD-B-one-fuel directory, although the applicants response to RAI 2-5 indicated that both of the 2.1% drop analyses have been updated.
The applicant should provide complete LS-DYNA file sets for the updated 2.1% drop analyses for review and verify that the files are uploaded correctly to the SharePoint site.
This information is needed to determine compliance with 10 CFR 71.71 (c) and 71.73(c).
2-2.
Explain the changes made to the load cases evaluated in Holtec Report HI-2167023-R6 and ensure the SAR is updated consistently.
2 The NCT load case N2 (1-ft side drop) has been re-analyzed with updated results presented in the revised Holtec Report HI-2167023-R6. The reasoning for the revised analysis is not discussed but may include the same changes made to the 2.1% loading cases in response to RAI 2-5, dated November 7, 2022. Additionally, the selected results of the SAR have not been updated to be consistent with the report. For example:
The stress intensity results in table 8.3 of HI-2167023-R6 have been updated with the results of this revised analysis; however, the results of table 2.6.6 of the SAR have not been updated to reflect the new calculated stress intensity values and safety factors.
Figure 8.10.2 has been updated in HI-2167023-R6; however, figure 2.6.5 of the SAR has not been updated to reflect this change.
The previous version of appendix H from Holtec Report HI-2167023-R5 documented two analyses for 50% loading cases that were stated to be consistent with the F-32 basket partial loading pattern considered in the shielding analysis. The updated appendix H from Holtec Report HI-2167023-R6 no longer includes these 50% loading cases.
The applicant should: (i) provide an explanation of the changes made to NCT load case N2 and update the SAR results to be consistent with HI-2167023-R6, and (ii) explain why the 50% loading cases are no longer included in the latest revision of appendix H from Holtec Report HI-2167023-R6 and verify that these cases are not required to support the shielding evaluations or assumptions.
This information is needed to determine compliance with 10 CFR 71.71(c) and 71.73(c).
2-3 Provide the materials of construction and qualification data (e.g., manufacturer data sheets or other testing) for the quiver seal/gasket materials that support the SAR maximum temperature limits and the capability to maintain the quivers leaktightness criteria per the operational requirements in SAR table 7.1.8 In its RAI 2-7, dated November 7, 2022, staff asked for the design documentation of the quiver to support the safety review of its mechanical performance and sealing capability.
Staff specifically requested the (i) structural materials of construction, including governing codes and standards; weld design, fabrication, and examination codes and standards; mechanical properties used in the structural analysis, and (ii) seal/gasket materials of construction in sufficient detail to support the SAR maximum temperature limits and the capability to maintain the quivers leaktightness criteria. The applicant did not provide the requested documentation.
This information is needed to demonstrate compliance with 10 CFR 71.33, 71.43, 71.71 and 71.73.
CHAPTER 5 SHIELDING REVIEW 5-1 Justify that the HI-STAR 80, when loaded with quivers that contain fuel debris, will meet regulatory dose rate limits when considering the reconfiguration of the source term.
The staff has found that the response to RAI 5-1, dated November 7, 2022, is not adequate. In the response to RAI 5-1, Holtec has stated that Quivers are bundles of a
3 limited number of sealed steel tubes where each tube contains just a single rod (or the remnants thereof). See Figure 1.2.2 for a side view. Hence there is no large open volume at the bottom (or top) of the quiver where broken parts of individual rods could accumulate.
Although figure 1.2.2 appears to show separate tubes, this is not a licensing drawing.
Further, it is stated that it is a typical quiver. Therefore, the structural integrity of the quivers cannot be credited within the shielding evaluation. Even if the structural integrity of the quiver is demonstrated, because the quiver is allowed to contain broken fuel rods and fuel debris, the shielding evaluation still needs to demonstrate that the HI-STAR 80, considering the burnup profile associated with the quivers, is within regulatory limits under NCT and HAC.
The burnup profile of intact spent fuel assemblies is peaked near the center and when considering fuel debris within the quivers, there would not be any burnup profile associated with this material; therefore, broken rods and fuel debris should not be modeled with a decreased source term near the top and bottom extremities.
This information is needed to determine compliance with 10 CFR 71.47 and 71.51(a)(2).
ML23080A124; ML23080A126 OFFICE NMSS/DFM/STLB NMSS/DFM/STLB NMSS/DFM/MSB NMSS/DFM
/NARAB NAME PSaverot WWheatley OKhan LCrevelt DATE Mar 21, 2023 Mar 22, 2023 Mar 22, 2023 Mar 22, 2023 OFFICE NMSS/DFM/MSB NMSS/DFM/MSB NMSS/DFM
/CTCFB NMSS/DFM/STLB NAME YKim TBoyce JPiotter YDiaz-Sanabria DATE Mar 22, 2023 Mar 23, 2023 Mar 23, 2023 Mar 24, 2023 OFFICE NMSS/DFM/FFLB NMSS/DFM/STLB NAME JZimmerman PSaverot DATE Mar 24, 2023 Mar 26, 2023