ML23118A008

Request for Additional Information for Review of the Certificate of Compliance No. 3098, Model No.GP-01

ML23118A008
Person / Time
Site:	07103098
Issue date:	05/24/2023
From:	Garcia-Santos N Storage and Transportation Licensing Branch
To:	Boyle R US Dept of Transportation (DOT), Office of Hazardous Materials Safety
Garcia-Santos N
Shared Package
ML23101A187	List: ML23101A188 ML23101A189 ML23118A008 ML23131A099 ML23131A100
References
A33010, EPID L -2023-DOT-0002
Download: ML23118A008 (10)

Text

May 24, 2023 Richard W. Boyle, Chief Sciences Branch Division of Engineering and Research Office of Hazardous Materials Safety U.S. Department of Transportation 1200 New Jersey Ave., S.E.

Washington, D.C. 20590

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION FOR REVIEW OF THE CERTIFICATE OF COMPLIANCE NO. 3098, MODEL NO. GP-01 (EPID L-2023-DOT-0002)

Dear Mr. Richard W. Boyle:

By letter dated January 25, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML23026A141), as supplemented on February 10, 2023 (ML23044A098), February 16, 2023 (ML23047A503), and March 6, 2023 (ML23066A261), you submitted an application requesting a review of the Japanese Approval Certificate Number J/2009/AF-96, Revision 1, Model No. GP-01 transport package, and make a recommendation concerning the revalidation of the package for import and export use.

In connection with our review, we need the information identified in the enclosure to this letter.

To assist us in scheduling the staff review of your response, we request that you provide this information three weeks after the date of this letter. Inform us at your earliest convenience, but no later than June 2, 2023, if you are not able to provide the information by that date. If you are unable to provide a response by the proposed timeline, our review may be delayed.

Please reference Docket No. 71-3098 and EPID -2023-DOT-0002 in future correspondence related to this request. The staff is available to meet to discuss your proposed responses. If you have any questions regarding this matter, I may be contacted at ngs@nrc.gov.

Sincerely, Norma Garcia Digitally signed by Norma Garcia Santos Santos Date: 2023.05.24 15:41:44

-04'00' Norma García Santos, Project Manager Storage and Transportation Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards Docket No. 07103098 EPID L -2023-DOT-0002

Enclosure:

Request for Additional Information

Request for Additional Information U.S. Department of Transportation Japanese Approval Certificate No. J/2009/AF-96 Docket No. 71-3098 Certificate of Compliance No. 3098 Model No. GP-01 By letter dated January 25, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML23026A141), as supplemented on February 10, 2023 (ML23044A098), February 16, 2023 (ML23047A503), and March 6, 2023 (ML23066A261), you submitted an application requesting a review of the Japanese Approval Certificate Number J/2009/AF-96, revision 1, Model No. GP-01 transport package, and make a recommendation concerning the revalidation of the package for import and export use.

This request for additional information (RAI) identifies information needed by the U.S. Nuclear Regulatory Commission (NRC) staff (the staff) in connection with its review of the application.

The staff used International Atomic Energy Agency (IAEA) Specific Safety Requirements No. 6 (SSR-6), Regulations for the Safe Transport of Radioactive Material, 2018 Edition, in its review of the application.

The 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 the IAEA SSR-6, 2018 Edition.

GENERAL (GEN)

RAI-GEN-1 Replace all references in the GP-01 application to TS-G-1.1, Advisory Material for the IAEA Regulations for the Safe Transport or Radioactive Material, with SSG-26 (Rev 1), Advisory Material for the IAEA Regulations for the Safe Transport or Radioactive Material (2018), to appropriately coincide with the use of SSR-6, Revision 1 (2018 Edition) for this application (or safety analysis report).

In the GP-01 application, page II - B - 9 (for example), the applicant refers to TS-G-1.1, which since the application has been revised to meet the requirements of SSR-6, 2018 Edition, the correct reference should be to SSG-26 (Revision 1),

The SSG-26 is the Advisory Material that corresponds to SSR-6, 2018 Edition.

Note that for this particular reference to TS-G-1.1, paragraph 728.31 has not changed in SSG-26 (Revision 1), so the paragraph reference is still correct.

This information is needed to determine compliance with the requirements in paragraph 102 of the IAEA SSR-6, 2018 Edition.

Enclosure

STRUCTURAL EVALUATION (St)

RAI-St-1 Provide the following information:

a. the damping value considered to determine the amplitude amplification factor provided in chapter II-A.4.7 of the application as well as the basis to choose the damping value.

b. clarify the statement provided in chapter II-A.4.7 of the application that refers to a conservative amplification, when the damping value considered is stated to be non-conservative (i.e., without conservative consideration).

Chapter II-A.4.7 of the application evaluates the effects of vibration or vibration resonance that may arise under routine condition of transport. In this chapter, it currently states, As shown in (II)-A Figure 13, at a frequency ratio of 0.67 (=20/29.8), the displacement amplitude factor is about 200% even without conservative consideration of damping. Generally, acceleration of the vibration generated by trailers, etc., during transport is less than 2G, even taking into account the passing over bumps, etc., so the load on the packaging is less than four times the load on the package, even if amplification is conservatively considered to be 200%. [emphasis added]

The statement above seems to be contradictory in terms of the conservatism of the damping value.

This information is needed to determine compliance with the requirements in paragraph 613 of the IAEA SSR-6, 2018 Edition.

MATERIALS EVALUATION RAI-M-1 Explain whether the new sentence quoted below describes a new material, new subcomponent, and/or modification to an existing material and/or subcomponent for a safety-related component of the GP-01 package. If this is the case, provide and explain the reason for this change and justify how it is suitable for its intended safety-related application.

On page I-3 of the 2022 GP-01 application, third to last sentence of the paragraph under section II, Lid of outer receptacle, the applicant states the following:

The surface of aluminum honeycomb cover are applied to two (2) anti-interference spacers of neoprene rubber 2 mm in thickness.

The staff noted that this specific sentence is not included in the 2018 version of the GP-01 application. The reason for this change is not clear to the staff, and it is not explained in the application. Additionally, the application does not show that this change meets IAEA SSR-6, Revision 1.

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This information is needed to determine compliance with the requirements in paragraphs 614 and 648 of the IAEA SSR-6, 2018 Edition.

RAI-M-2 Explain whether the new underlined text quoted below represents a new material, new subcomponent, and/or a modification to an existing material and/or subcomponent for a safety-related component of the GP-01 package. If this is the case, provide and explain the reason for this change and justify how it is suitable for its intended safety-related application.

On page I-4 of the 2022 GP-01 application, last two sentences of the paragraph under section VIII, Fusible plugs, the applicant states the following:

A fusible plug is installed in the center of each face of the outer receptacle and lid of the outer receptable (six pieces in total). The melting temperature of solder is approximately 180 °C.

The staff noted that the corresponding location in the 2018 version of the GP-01 application does not include the underlined text. The reason for this change is not clear to the staff, and it is not explained in the application. Additionally, the application does not show that this change meets IAEA SSR-6, Revision 1.

This information is needed to determine compliance with the requirements in paragraphs 614 and 648 of the IAEA SSR-6, 2018 Edition.

RAI-M-3 Explain whether the changes shown in table I-1 (described below) for the rubber items of the outer receptacle lid represent a new material, new subcomponent, and/or a modification to an existing material and/or subcomponent for a safety-related component of the GP-01 package. If so, also provide and explain the reason for the changes and justify how they are suitable for the intended safety-related application.

In the 2022 GP-01 application, page I-10, table I-1, Major Materials for the Packaging Components (1/2), the applicant lists outer receptacle lid components and materials including:

an Anti-interference spacer made of Neoprene rubber (chloroprene rubber) and Fire-resistant rubber made of Ethylene propylene rubber.

The staff noted that the corresponding rubber subcomponent information for the outer receptacle lid in this table in the 2018 version of the GP-01 application lists only a Spacer made of Fire-resistant rubber rather than the two separate rubber items identified in the 2022 version. The reason for these changes is not clear to the staff, and it is not explained in the revalidation application submittal.

Additionally, the application does not show that this change meets IAEA SSR-6, Revision 1.

This information is needed to determine compliance with the requirements in paragraphs 614 and 648 of the IAEA SSR-6, 2018 Edition.

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RAI-M-4 Explain the reason for the change in the temperature ranges specified for the inner receptacle flange O-ring in the first two sentences in section C.2.3, Gasket and welds of containment system, on page II-C-2 of the 2022 version of the application. Also, considering the information from the application cited below, justify how the new temperature ranges in these sentences are consistent with the service temperature range of -50°C to 180°C specified for the inner receptacle flange O-ring in section B.3, Characteristics of Packaging Components, (page II-B-4) and the upper service temperature limit of 180°C specified for this O-ring in section C.3, Normal Conditions of Transport, subsection (1), Thermal Test, (page II-C-2).

The first two sentences in section C.2.3 of the 2022 version of the GP-01 application state the following:

The material (silicone rubber) of the O-ring provided on the inner receptacle flange maintains its thermal strength in a temperature range from -40°C to +38°C. Deterioration does not occur in the material in the temperature range of -40°C to 38°C.

The staff noted that the corresponding sentences in the 2018 version of the application specified different temperature ranges of -50°C to 180°C (first sentence) and -40°C to 70°C (second sentence). The staff noted that the changes to these temperature ranges in the first two sentences in section C.2.3 of the 2022 version of the GP-01 application appear to be inconsistent with the service temperature range specified in section B.3 and the upper service temperature limit specified in section C.3, subsection (1), as cited above.

This information is needed to determine compliance with the requirements in paragraphs 616 and 639 of the IAEA SSR-6, 2018 Edition.

RAI-M-5 Explain the reason for the changes in the atom densities for the nuclides that are specified for the package component materials in table II-E-1, Atom Densities of Materials Used for Calculations, on page II-E-10 of the 2022 version of the application. Show that the revised atom densities are appropriate for the material components.

The staff noted that the atom densities for the nuclides that are specified for the package component materials in table II-E-1, Atom Densities of Materials Used for Calculations, (page II-E-10) in the 2022 version of the application have changed significantly from those specified in this corresponding table in the 2018 version of the application. The reason for the changes is not clear to the staff, and it is not explained in the revalidation application submittal. Additionally, the application does not show that the change in atom desities is appropriate for the material.

This information is needed to determine compliance with the requirements in paragraph 673, 682, and 726 of the IAEA SSR-6, 2018 Edition .

RAI-M-6 Provide a complete evaluation of fatigue for the reusable package components for the 80-year period of use (and the 160 transports that are allowed during the 80-year period) that considers the combined effects of all applicable types of 4

accumulated stress cycles in components during normal service conditions, including the following cycle types (as described in this question):

a. Lifting cycles

b. Inner receptacle pressurization cycles

c. Vibration cycles

d. Thermal stress cycles If certain types of stress cycles are considered to be not applicable or negligible for certain components, explain why these are not applicable or are negligible.

If such a complete fatigue evaluation cannot be performed, or if the fatigue evaluation cannot show adequate protection against fatigue failure considering the combined effects of all applicable types of accumulated stress cycles in components, provide the following information:

a.1 a description about how periodic maintenance inspections will be used to identify and address fatigue cracks in components of the package b.1 A description of the corrective actions that will be taken for any detected fatigue cracks, such as analytical flaw evaluation with follow-up inspections, repair/replacement of components with cracks, etc.

The following provide additional descriptions about accumulated stress cycles as provided in the application:

1. Lifting cycles - The staff recognizes that these cycles are already evaluated in sections A.4.4.10 and II-F, tables 1 and 2. However, the staff noted that the lifting cycles are evaluated without considering the other types of stress cycles that may also be accumulated by the lifting devices.

To perform an adequate analytical evaluation that demonstrates sufficient safety margin against fatigue failure of these components, the combined effects of accumulated lifting cycles along with other applicable types of accumulated stress cycles in these components (including consideration of cycle types listed herein) on the potential for fatigue of lifting devices should be considered.

2. Inner receptacle pressurization cycles - The staff recognizes that these cycles are already evaluated in sections A.4.6.3 and II-F, tables 1 and 2.

However, the staff noted that the inner receptacle pressurization cycles are evaluated without considering other types of stress cycles that may also be accumulated by the inner receptacle components. To perform an adequate analytical evaluation that demonstrates sufficient safety margin against fatigue failure of these components, the combined effects of accumulated pressurization cycles along with other applicable types of accumulated stress cycles in these components (including consideration 5

of cycle types listed herein) on the potential for fatigue of inner receptacle components should be considered.

3. Vibration cycles - The staff noted that section A.4.7 and Appendix 3 to section II-A of the application provide an evaluation that demonstrates that package resonance is a not a concern considering package vibration caused by vehicle transport over bumpy road conditions. However, the staff noted that this evaluation:

i. only evaluates the peak vertical acceleration experienced by package components based on the natural frequency of the package and the peak vertical acceleration and excitation frequency generated by the truck driving over road bumps.

ii. does not address the potential for fatigue of package components due to the combined effects of the accumulation of a very large number of vibration cycles resulting from the 160 allowed transports of the package (with each transport experiencing long distances over potentially bumpy roads), along with the accumulation of other applicable types of stress cycles, including consideration of the cycle types listed herein.

4. Thermal stress cycles - The staff could not locate any evaluation of the potential for fatigue of components that accounts for accumulated thermal stress cycles in components. Thermal stress cycles may occur in components due cyclical fluctuation of spatial temperature gradients within components and cyclical temperature fluctuations for assembled or joined components made of dissimilar materials that are dimensionally constrained, such as the chrome-molybdenum steel bolts in tight contact with the threaded holes in stainless steel receptacle components.

In order to determine that fatigue is not an aging concern, as indicated in section II-F of the application, the staff needs a complete fatigue evaluation that considers the combined effects of all applicable types of stress cycles during normal service, including consideration of the cycle types listed above. The complete fatigue evaluation that considers all applicable cycle types should demonstrate adequate protection against fatigue failure based on the applicable fatigue failure curve for the material. If such a complete fatigue evaluation cannot be performed, or if the fatigue evaluation cannot show adequate protection against fatigue failure, then, periodic maintenance inspections of the packages components should include the examination of components for early stage fatigue cracks, and corrective actions (analytical flaw evaluation with follow-up inspections, repair/replacement of components with cracks, etc.) should be specified for detected fatigue cracks.

This information is needed to determine compliance with the requirements in paragraphs 503(e), 613, 613A, and 809(f) of the IAEA SSR-6, 2018 Edition.

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RAI-M-7 Confirm that the definition of stress amplitude for the stress cycles corresponds directly to the definition of stress amplitude for the material fatigue failure curves for stainless steel and chrome-molybdenum steel.

Sections A.4.4.10, A.4.6.3, and section II-F, tables 1 and 2, evaluate lifting cycles and inner receptacle pressurization cycles by considering stress amplitude, which is defined in these sections as one-half the total stress range for each cycle for the most highly stressed locations.

This information is needed to determine compliance with the requirements of the paragraphs 613 and 613A of the IAEA SSR-6, 2018 Edition.

RAI-M-8 Provide a description of any national or international codes, standards, and/or other methods, programs, or procedures that are implemented to ensure that package maintenance activities (including visual inspections, screening and evaluation of visual indications, and corrective actions such as component repairs and replacements) are adequate to manage the effects of aging in metallic package components that would see long-term use, such that the package components are capable of performing their required safety functions throughout the period of use.

The staff requests that this description address the following criteria:

1. Inspection methods (e.g., bare metal visual exams and/or other types of nondestructive exams such as liquid penetrant exams or ultrasonic exams) for detection, characterization, and sizing of localized aging effects such as cracks, pits, and crevice corrosion.

2. Inspection equipment and personnel qualification requirements (e.g., lighting and visual acuity requirements for performing visual exams) to ensure reliable inspections that can adequately detect and characterize indications of localized aging effects prior to component failure or loss of safety function.

3. Visual criteria for detection of aging effects such as early stage fatigue cracks (if fatigue cannot be screened out by analytical evaluation per RAI-M-6 above) and localized corrosion of stainless steel components, such as chloride induced stress corrosion cracking (SCC), pitting, and crevice corrosion. Examples of visual indications that may indicate potential localized corrosion of stainless steel components include the accumulation of atmospheric deposits such as salts, buildup of corrosion products, rust-colored stains or deposits, and surface discontinuities or flaws associated with pitting, crevice corrosion, and/or SCC.

4. Describe any surface cleaning requirements that are implemented to ensure that bare metal visual inspections of component surfaces are capable of detecting surface flaws, and for ensuring adequate removal of atmospheric deposits such as salts or other chemical compounds that may contribute to localized corrosion of stainless steel components.

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5. Describe any flaw evaluation methods (such as flaw sizing and flaw analysis methods) and associated flaw acceptance criteria that may be used to determine whether components containing flaws are acceptable for continued service.

In Section III-B of the application, the applicant provided a description of the maintenance criteria, including visual inspection criteria, that are relied on for detecting very significant conditions of damage or deterioration in the package components during the 80-year period of use, such as deformation, fracture, cracks, and missing or displaced components, etc. Nevertheless, this section does not describe any codes, standards, methods, programs, procedures, or other documents to ensure that aging effects will get detected and corrected prior to causing a loss of safety function in the components. For effective aging management, the five criteria requested above are generally considered to be elements of effective maintenance programs that can be relied on to adequately detect and manage aging effects prior to a loss of safety function.

This information is needed to determine compliance with the requirements in paragraphs 503(e), 613A, and 809(f) of the IAEA SSR-6, 2018 Edition.

RAI-M-9 Explain whether or not maintenance inspections are truly voluntary or whether they are actually required to be performed to ensure that reusable package components are maintained in a condition to ensure they are capable of performing their required safety functions in accordance with applicable regulatory requirements.

The maintenance inspections are described throughout sections II-F, II-G, and III-B as voluntary inspections. For used packages, the IAEA SSR-6, 2018 Edition requires that used packages shall consider aging mechanisms in their safety analysis and shall "have been been maintained during storage in a manner such that all the requirements specified in the relevant provisions of these Regulations and in the applicable certificates of approval have been fulfilled.

This information is needed to determine compliance with requirements in paragraphs 503(e), 613A, and 809(f) of the IAEA SSR-6, 2018 Edition.

RAI-M-10 Explain whether the maintenance criteria described in Section III-B of the application are applicable to both the packaging components and the components of the contents that are used repeatedly that are scoped into the aging evaluation. If the maintenance criteria described in Section III-B do not include the components of the contents that are used repeatedly, please describe the maintenance activities, including inspection and component repair/replacement criteria, that are performed for the content components that are used repeatedly.

The aging evaluation in Section II-F of the GP-01 application includes both packaging components and components of the contents that are used repeatedly. Per Section II-F, Subsection F.2, Evaluation of the need to consider aging in safety analysis, components of the contents that are used repeatedly include the stainless steel pellet storage box, stainless steel pellet storage box 8

assembly structural items, and borated stainless steel intermediate partition plate neutron absorber.

The maintenance criteria described in Section III-B of the application describe periodic visual inspections of packaging components, including internal and external surfaces of the body and lid of the inner and outer receptacle, welds, nuts and bolts, rubber items such as spacers and skids, boronic stainless steel plates, lifting attachment welds, and O-rings. The maintenance criteria indicate that packaging components that do not satisfy the visual inspection criteria are to be repaired or replaced. However, it is unclear whether the periodic visual inspections and repair/replacement criteria are also applicable to the components of the contents that are used repeatedly, as specified in Section II-F, Subsection F.2.

This information is needed to determine compliance with requirements in paragraphs 503(e), 613A, and 809(f) of the IAEA SSR-6, 2018 Edition.

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