ML23045A091
| ML23045A091 | |
| Person / Time | |
|---|---|
| Site: | 07109365 |
| Issue date: | 02/27/2023 |
| From: | Allen C Storage and Transportation Licensing Branch |
| To: | Shakhatreh A Robatel Technologies |
| References | |
| EPID L-2022-LLA-0134 | |
| Download: ML23045A091 (6) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Abdulsalam Shakhatreh Engineering Manager Robatel Technologies 5115 Bernard Drive Suite 304 Roanoke, VA 24018
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION FOR REVIEW OF THE MODEL NO. RT-100 PACKAGE
Dear Abdulsalam Shakhatreh:
By letter dated August 29, 2022 (Agencywide Documents Access and Management System
[ADAMS] Accession No. ML22262A264), as supplemented November 22, 2022 (ADAMS Accession No. ML22335A081), you submitted an application to amend Certificate of Compliance No. 9365 for the Model No. RT-100 package to add activated hardware as new contents and provide flexibility to ship filters of varying activities. To assist with our review, the U.S. Nuclear Regulatory Commission staff (NRC, the staff) needs the information identified in the enclosure to this letter.
We request that you provide this information by April 7, 2023. Inform us at your earliest convenience, but no later than March 31, 2023, if you are not able to provide the information by that date. If you are unable to provide a response by April 7, 2023, please propose a new submittal date with the reasons for the delay. Please reference Docket No. 71-9365 and EPID No. L-2022-LLA-0134 in future correspondence related to this amendment request. The staff is available to discuss these questions as well as your proposed responses. If you have any questions regarding this matter, feel free to contact me at (301) 415-6877.
Sincerely, Chris Allen, Project Manager Storage and Transportation Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards Docket No. 71-9365 EPID No. L-2022-LLA-0134
Enclosure:
Request for Additional Information cc w/encl:
71bw9365all@listmgr.nrc.gov February 27, 2023 Signed by Allen, William on 02/27/23
Request for Additional Information Docket No. 71-9365 Model No. RT-100 Package
By letter dated August 29, 2022 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML22262A264), as supplemented November 22, 2022 (ADAMS Accession No. ML22335A081), Robatel Technologies, LLC (Robatel, the applicant) submitted an application to amend Certificate of Compliance No. 9365 for the Model No. RT-100 package to add activated hardware as new contents and provide flexibility to ship filters of varying activities. This request for additional information letter identifies information needed by the U.S Nuclear Regulatory Commission (NRC, the staff) in connection with its review of the application.
NUREG-2216, Standard Review Plan for Transportation Packages for Spent Fuel and Radioactive Material," was used by the staff in its review of the application.
Each individual request for additional information describes information needed by the staff to complete its review of the application to determine whether the applicant has demonstrated compliance with the regulatory requirements.
STRUCTURAL
2.1 Demonstrate how evaluating cold conditions of normal conditions of transport (NCT) using both a maximum internal pressure and decay heat results in the most unfavorable cask stresses.
Both section 2.2 and table 1 of Regulatory Guide 7.8, as well as section 2.4.5.2 of NUREG-2216, state that the cold conditions be evaluated with minimum internal pressure loads and without decay heat. However, safety analysis report (SAR) sections 2.6.1.1 and 2.6.2 indicate that both an increased internal pressure of 342.7 kPa (versus the calculated 182.71 kPa) and an internal heat load were considered in the cask analyses for the cold conditions.
The above information is necessary to comply with Title 10 of the Code of Federal Regulations (10 CFR) 71.71(c)(2).
2.2 Identify the maximum internal cask pressure employed in the various NCT evaluations and the hypothetical accident conditions (HAC) fire accident.
SAR sections 2.6.1.1, 3.1.4 (table 3.1.4-1) and 3.3.2.5 indicate that a conservatively increased internal cask pressure of 342.7 kPa is employed for NCT evaluations, as well as some HAC evaluations, versus a calculated value of 182.7 kPa. However, SAR sections 2.6.3, 2.6.7.2.2, 2.7.1, 2.7.3.1.1, 2.13.2.1.1, 2.13.2.1.3 and Tables 2.13.3-1 and 2.13.3-2 indicate that a value of 242 kPa is employed. For HAC fire accident conditions, SAR sections 2.7.4.3.2, 2.13.2.1.2, 2.13.2.1.4, 3.1.4 (Table 3.1.4-1) and 3.4.3.2.5 indicate that a maximum accident internal cask pressure of 689.4 kPa is employed. However, SAR sections 2.6.7.2.2 and 2.7.1 indicate that a value of 588 kPa is employed. It appears that the gauge and absolute pressure values are being used interchangeably.
Enclosure This information is necessary to demonstrate compliance with 10 CFR Parts 71.71 for NCT and 71.73 for HAC.
2.3 Demonstrate how the omission of thermal expansion effects in the evaluation of HAC drop conditions with hot ambient conditions results in the most unfavorable cask stresses.
SAR section 2.7.1 states that cask stresses induced by thermal expansion are not considered for the accident drop conditions. This approach follows neither the recommendations in table 1 of Regulatory Guide 7.8 nor section 2.4.6.1 of NUREG-2216 for hot initial ambient conditions.
This information is necessary to demonstrate compliance with 10 CFR 71.73(b).
2.4 Demonstrate that the most unfavorable closure bolt stresses for the applicable HAC loading combinations have been determined.
It appears that the temperature values presented in table 3.1.3-2 (for HAC pin puncture at top impact limiter) were employed in calculating the bolt stresses presented in SAR section 2.13.2.2.2. However, staff believes using the temperatures provided in SAR table 3.1.3-3 result in greater bolt stresses.
This information is necessary to demonstrate compliance with 10 CFR Parts 71.43(f) and 71.51(2).
2.5 Revise the SAR to address vibration-induced bolt loads including prying effects.
The applicant stated in their letter dated November 22, 2022 (ADAMS Accession No. ML22335A081), that the vibration-induced loads, based on a vertical loading of two times the lid weight, were not addressed in the SAR due to their low magnitude and insignificant contribution to overall bolt stress demand. The SAR needs to be updated to address these loads. When updating the SAR, the applicant should correct unit errors in the calculation provided in ML22335A081.
This information is necessary to demonstrate compliance with 10 CFR 71.71(c)(5).
2.6 Address the following items on SAR tables 2.13.3-1 and 2.13.3-2:
- a. The last two columns of the tables are labeled Prying Force and Prying Moment, however, the values listed are actually fixed-edge closure-lid forces and moments (i.e., Ff and Mf in NUREG/CR-6007).
- b. Identify the source of the minimum preload Non-Prying Tensile Force and Torsional Moment values provided in both tables.
- c. Check the table 2.13.3-2 entry for Puncture Non-Prying Tensile Force as it does not appear to agree with the value presented in SAR section 2.13.2.5.1.2.
- d. Identify the source of the puncture, free drop (NCT) and free drop (HAC)
Torsional Moment values provided in both tables.
- e. Include vibration-induced loading in the tables.
The cited tables require updating to correct the headings, to list all of the imposed bolt loads, and to correct values as necessary to match those presented in the SAR. In the
2 case of the minimum preload loading values presented, staff was unable to locate a rationale or calculation for these values in the SAR. Similarly, the source of the torsional loads presented as resulting from puncture and NCT and HAC free drop conditions could not be located in the SAR. The applicant should confirm that the most unfavorable closure bolt stresses for all loading combinations have been determined after making the changes identified above. The applicant should confirm that the most unfavorable closure bolt stresses for all loading combinations have been determined after making the changes identified above.
This information is necessary to demonstrate compliance with 10 CFR Parts 71.51(a)(1) and 71.51(a)(2).
2.7 Demonstrate that low-cycle fatigue for lid closure bolts is not an issue and revise the SAR as necessary.
NUREG-2216 section 2.4.5.5 provides guidance to employ NUREG/CR-6007 for evaluation of fatigue bolt stresses. Table 6.2 of NUREG/CR-6007 references the American Society of Mechanical Engineers Code,Section III, Appendix I bolt fatigue stress acceptance criteria. It does not appear that the combined bolt loads determined in SAR sections 2.13.3.1 and 2.13.3.2 are evaluated against the American Society of Mechanical Engineers Code criteria.
This information is necessary to demonstrate compliance with 10 CFR 71.71.
2.8 Provide a means to ensure that the stated minimum horizontal gap at all lid closure bolts is achieved prior to shipment and during transport to ensure that shear load transfer to the lid closure bolts is circumvented.
SAR section 2.13.2.1.1 states that shear load effects on the primary lid bolts are prevented due to designed gaps between lid and cask wall, and subsequently lid and bolt, including fabrication tolerances shown on the design drawings. The applicant explained in their letter dated December 14, 2022 (ADAMS Accession No. ML22356A047), that for all existing fabricated RT-100 models, the actual fabricated dimensions of the lids and bolts have been calculated and provide sufficient gaps to prevent the interior of the bolt holes from contacting the lid closure bolts in the pre-shipment condition. The applicants calculations employ the exact dimensions of existing containers and assume the lids will be installed concentrically around the bolts. However, were the lid to be installed non-concentrically such that the interior of the lid bears on the inner diameter of the cask, the gap size is reduced to nominally 0.5 mm. Consider including a post-lid-installation inspection procedural step to verify the minimum horizontal clearance dimension is realized for every bolt prior to shipment. For example, using a template around the perimeter of each bolt head to confirm that the minimum gap exists between the exterior surface of each lid closure bolt head and the interior of the associated bolt hole has the potential to address this concern. It is quite possible for this gap to be eliminated entirely during the installation of the lids or during thermal growth or shrinkage during transport conditions, thereby imparting shear loads to one or several of the lid closure bolts. To verify that there is no contact during transport conditions, consider performing a thermal analysis to show that the lid does not bear on any bolt during expansion or contraction conditions. It is not clear in the SAR whether the bolts have the capacity to withstand the additional shear loading, during either NCT or HAC loading combinations. The addition of
3 an inspection step after completion of lid installation for each transport use emphasizes the importance of verifying this design aspect.
This information is necessary to demonstrate compliance with 10 CFR Parts 71.43(f) and 71.51(a)(1) for NCT and 10 CFR 71.51(a)(2) for HAC.
MATERIALS
7.1 Provide additional details on how hydrogen generation, by either galvanic or chemical reactions, was accounted for in analyzing the package contents.
The applicant stated that the contents of the package may contain a mixture of spent resins, spent filters and activated hardware which may have a potential for hydrogen generation as a result of galvanic or chemical reactions. NUREG/CR-6673 is referenced in the application for the evaluation of hydrogen generation by radiolysis and to determine shipping duration. However, NUREG/CR-6673 only considers hydrogen formation due to radiolysis and does not address hydrogen generation from chemical reactions, thermal degradation, or biological activity. In addition, Appendix A of NUREG/CR-6673 indicates that hydrogen generation by chemical reactions can be significant. The staff is unclear how the applicant made the determination that the package contents would not cause chemical or galvanic reactions that could generate hydrogen.
This information is required to meet the requirements of 10 CFR 71.43(d).
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Ltr ML23045A091 OFFICE NSIR/DPR NMSS/DFM/MSB NMSS/DFM/MSB NMSS/DFM/MSB NAME JGoodridge JGOKhan OK JSmith JSTBoyce TB DATE Feb 17, 2023 Feb 14, 2023 Feb 15, 2023 Feb 17, 2023 OFFICE NMSS/DFM/STLB NMSS/DFM/STLB NAME YDiaz-Sanabria YDWAllen WA DATE Feb 24, 2023 Feb 27, 2023