ML20035C759

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Redacted - Kewaunee, Request for Exemption from Certain Code of Federal Regulation Requirements of Certificate of Compliance No. 1031 for the NAC Magnastor Storage System
ML20035C759
Person / Time
Site: Kewaunee  Dominion icon.png
Issue date: 01/16/2020
From: Mark D. Sartain
Dominion Energy Kewaunee
To:
Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
White B
References
19-492
Download: ML20035C759 (26)
v • d • e


Text

  • PROPRIETARY INFORMATION-WITHHOLD UNDER 10 CFR 2.390 Dominion Energy Kewaunee, Inc:

5000 Dominion Boulevard, Glen Allen, VA 23060 ~ Dominion Dominion Energy.com pi' Energy January 16, 2020 ATTN: Document Control Desk Seric;1I No.: 19-492 Director, Division of Spent Fuel Management NRA/ENC: RO Office of Nuclear Material Safety and Safeguards Docket Nos.: 72-64 U.S. Nuclear Regulatory Commission 50-3.05 Washington, DC 20555-0001 License No.: DPR-43 DOMINION ENERGY KEWAUNEE, INC.

KEWAUNEE POWER STATION REQUEST FOR EXEMPTION FROM CERTAIN CODE OF FEDERAL REGULATION REQUIREMENTS OF CERTIFICATE OF COMPLIANCE NO. 1031 FOR THE NAC MAGNASTOR STORAGE SYSTEM.

Pursuant to 10 CFR 72.7, "Specific Exemptions," Dominion Energy Kewaunee, Inc. (DEK) requests an exemption from the requirements of 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(11 ), and 10 CFR 72.214 for each of the 24 MAGNASTOR Transportable Storage Canisters (TSCs) in use at the Independent Spent Fuel Storage Installation (ISFSI) at the Kewaunee Power Station as listed in Enclosure 1. This exemption is needed to resolve two non-conforming conditions associated with the procurement of material used in the fabrication of these canisters.

Specifically, an exception to the ASME Code Section Ill, Division 1, Subsection NG-2300, Charpy testing direction requirement for carbon steel plate material greater than%" thick and an exception to the post-heat treatment Ultrasonic Examination (UT) requirements for ASME Section Ill, Division 1, Subsection NG-2500, for rolled carbon steel plate material greater than%" is being requested.

Reference 1, Appendix A, Section 4.2 requires the TSC spent fuel basket design, material procurement, and fabrication and testing conform to the requirements of the ASME Code, 2001 Edition with Addenda through 2003, Section Ill, Subsection NG. Contrary to this requirement, the TSCs listed in Enclosure 1 do not fully conform to the applicable Code requirements. NAC International, the certificate holder for the MAGNASTOR cask system, has identified that TSCs listed in Enclosure 1 have spent fuel basket sub-components which do not meet the test specimen orientation requirements detailed in the Code. Enclosure 2 provides a list of the affected. spent fuel basket sub-components. In addition, NAC International has identified that the systems listed in Enclosure 1 have spent fuel basket sub-components which do not meet the post-heat treatment UT requirements detailed in the Code. Enclosure 3 provides a list of the affected spent fuel basket sub-components. ;JM S S ZLJ

.--~~~~~~~~~~~~~~~~~~~~~~N~MS~2~

Enclosures 5 and 6 contain information that is being withheld from public disclosure unde_r /1/fc.f__

10 CFR 2.390. Upon separation from Enclosures 5 and 6, this letter is decontrolled.

'--~~~~~~~~~~~~~~~~~------~~--'NM5S

Serial No.: 19-492 Docket Nos.: 72-64, 50-305 Page 2 of 4 provides the exemption request, including a description of the need and justification for the issuance of an exemption. The exemption request provides the basis and technical justification for the continued use of TSCs already loaded and in storage.

In summary, the exemption request has determined that while not fully compliant with the Code requirements for impact testing and post-heat treatment UT examination, the material used in the fabrication of the spent fuel baskets is the required material and the affected subcomponents will continue to perform their intended safety functions.

An evaluation of test data comparing the difference in results for longitudinal verses transverse orientation of Charpy impact specimens is summarized in a White Paper authored by NAC International in Enclosure 5. A third-party engineering consultation, included in Enclosure 6, addresses the acceptability of plate material not meeting the post-heat treatment UT requirements of the Code. All of the content _in Enclosures 5 and 6 is considered proprietary to NAC International. Therefore, non-proprietary versions of these enclosures would be of no value to the public due to the amount of proprietary information included and are not provided.

Since Enclosures 5 and 6 contain information proprietary to NAC International, an Affidavit signed by NAC International, the O\*vner of the information, is included in supporting the basis on which the information may be withheld from public disclosure by the Nuclear Regulatory Commission and addresses with specificity the considerations listed in (b)(4) of 10 CFR 2.390. Accordingly, it is respectfully requested that the information which is proprietary to NAC International be withheld from public disclosure in accordance with 10 CFR 2.390.

DEK requests approval of this exemption request by May 29, 2020.

Please contact Erica N. Combs at 804-273-3386 if you have any questions or require additional information.

Sincerely, Mark D. Sartain Vice President - Nuclear Engineering and Fleet Support

Serial No.: 19-492 Docket Nos.: 72-64, 50-305 Page 3 of 4

Enclosures:

1. List of Affected Transportable Storage Canisters (TSCs)
2. List of Spent Fuel Basket Non-Compliant Sub-Components - Charpy V-notch Impact Testing
3. List of Spent Fuel Basket Non-Compliant Sub-Components - Post-Heat Treatment UT Examination
4. Exemption Request Need and Justification
5. 71160-WP-020, NAC International Assessment of Longitudinal Versus Transverse Charpy Impact Testing for A537 and A517 Materials, Rev. 2 [NAC International Proprietary Information]
6. Sperka Engineering Services, Inc.,

Subject:

Ultrasonic Examination After Normalizing, October 23, 2019 [NAC International Proprietary Information]

7. NAC International -Affidavit Pursuant to 10 CFR 2.390 Commitments made by this letter: None

References:

1. U. S. Nuclear Regulatory Commission (NRC) Certificate of Compliance No. 1031 for the NAC International MAGNASTOR Cask System, Amendment No. 6.

Serial No.: 19-492 Docket Nos.: 72-64, 50-305 Page 4 of 4 cc: Regional Administrator U.S. Nuclear Regulatory Commission, Region Ill 2443 Warrenville Road, Suite 210 Lisle, IL 60532-4352 Ted H. Carter Senior Project Manager - Kewanee Power Station U. S. Nuclear Regulatory Commission Mail Stop T-8F5 Two White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Bernie White Senior Project Manager U. S. Nuclear Regulatory Commission Mail Stop 4-816 Two White Flint North 11555 Rockville Pike Rockville, MD 20852-2738

Serial No.: 19-492 ENCLOSURE 1 List of Affected Transportable Storage Canisters (TSCs)

Kewaunee Power Station Dominion Energy Kewaunee, Inc. (DEK)

No.: 19-492 Enclosure 1 Page 1 of 1 Dominion Energy Kewaunee, Inc.

Certificate of Compliance No. 1031 Amendments Serial Number Model Non-Compliance1 MAG-TSC-30026-086-01 MAGNASTOR A and B MAG-TSC-30026-086-02 MAGNASTOR A and B MAG-TSC-30026-086-03 MAGNASTOR A and B MAG-TSC-30026-086-04 MAGNASTOR A and B MAG-TSC-30026-086-05 MAGNASTOR A and B MAG-TSC-30026-086-06 MAGNASTOR A and B MAG-TSC-30026-086-07 MAGNASTOR A and B MAG-TSC-30026-086-08 MAGNASTOR A and B MAG-TSC-30026-086-09 MAGNASTOR A and B MAG-TSC-30026-086-10 MAGNASTOR A and B MAG-TSC-30026-086-11 MAGNASTOR A and B MAG-TSC-30026-086-12 MAGNASTOR A and B MAG-TSCDF-30026-184-13 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-14 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-15 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-16 MAGNASTOR-DF A and B MAG-TSCDF-30026-184-17 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-18 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-19 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-20 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-21 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-22 MAGNASTOR - DF A and B MAG-TSCDF-30026-184-23 MAGNASTOR-DF , A and B MAG-TSCDF-30026-184-24 MAGNASTOR - DF A and B 1 Designation "A" indicates non-compliance with Charpy V-notch test specimen orientation code requirements. Designation "B" indicates non-compliance with post-heat treatment UT examination code requirements.

Serial No.: 19-492 ENCLOSURE 2 List of Spent Fuel Basket Non-Compliant Sub-Components -

Charpy V-notch Impact Testing Kewaunee Power Station Dominion Energy Kewaunee, Inc. (DEK)

Serial No.: 19-492 Enclosure 2 Page 1 of 1 Spent Fuel Basket Non-Compliant Sub-Components -

Charpy V-notch Impact Testing Bill of Materials License Drawing Number Component Name Item Number 71160-574 1 Corner Support Bar1 10 Center Plate 11 Center Plate 71160-575 15 Drive Pin 1 16 Spacer1 71160-674 1 Inner-Formed Plate 2 Inner-Formed Plate 3 Outer-Formed Plate 4 Ridge Gusset 71160-675 15 Drive Pin 1 16 Spacer1 1 If made from plate.

Serial No.: 19-492 ENCLOSURE 3 List of Spent Fuel Basket Non-Compliant Sub-Components -

Post-Heat Treatment UT Examination Kewaunee Power Station Dominion Energy Kewaunee, Inc. (DEK)

1 Serial No.: 19-492 Enclosure 3 Page 1 of 1 Spent Fuel Basket Non-Compliant Sub-Components -

Post-Heat Treatment UT Examination License Drawing Number Bill of Materials Component Name Item Number 71160-551 12 Mounting Boss 1 71160-574 1 Corner Support Bar1 71160-575 15 Drive Pin 1 16 Spacer1 71160-674 1 Inner-Formed Plate 2 Inner-Formed Plate 71160-675 15 Drive Pin 1 16 Spacer1 1

If made from plate.

Serial No.: 19-492 ENCLOSURE 7 NAC International -

Affidavit Pursuant to 10 CFR 2.390 Kewaunee Power Station Dominion Energy Kewaunee, Inc. (DEK)

NAC INTERNATIONAL AFFIDAVIT PURSUANT TO 10 CFR 2.390 George Carver (Affiant), Vice President, Engineering and Licensing, of NAC International, hereinafter referred to as NAC, at 3930 East Jones Bridge Road, Peachtree Comers, Georgia 30092, being duly sworn, deposes and says that:

1. Affiant has reviewecl the information described in Item 2 and is personally familiar with the tracle secrets and privileged information contained therein, and is authorized to request its withholding.
2. The information to be withheld includes the following NAC Proprietary Information that is being provided to suppo11 the technical review of Dominion Energy's request for an exemption to the requirements of Certificate of Compliance (CoC) (No. 1031) for the NAC International MAGNASTOR Cask System.
  • Enclosure 5 - 71160-WP-020, NAC International Assessment of Longitudinal Versus Transverse Charpy Impact Testing for A537 and AS 17 Materials, Rev. 2
  • Enclosure 6 - Sperko Engineering Services, Inc.,

Subject:

Ultrasonic Examination After Normalizing, October 23, 2019 NAC is the owner of the infonnation contained in the above documents. Thus, all of the above identified information is considered NAC Proprietary Information.

3. NAC makes this application for withholding of proprietary information based upon the exemption from disclosure set fotth in: the Freedom oflnformation Act (F0IA"); 5 USC Sec. 552(b)(4) and the Trade Secrets Act; 18 USC Sec. 1905; and NRC Regulations 10 CFR Patt 9.I7(a)(4);

2.390(a)(4), and 2.390(b)(l) for "trade secrets and commercial financial information obtained from a person, and privileged or confidential" (Exemption 4). The information for which exemption from disclosure is herein sought is all "confidential commercial information," and some portions may also qualify under the narrower definition of "trade secret," within the meanings assigned to those tenns for purposes ofFOIA Exemption 4.

4. Examples of categories of information that fit into the definition of proprietary information are:
a. Information that discloses a process, method, or apparatus, including supporting data and analyses, where prevention of its use by competitors of NAC, without license from NAC, GOnstitutes a competitive economic advantage over other companies.
b. Information that, if used by a competitor, would reduce their expenditure of resources or improve their competitive position in the design, manufacture, shipment, installation, assurance of quality or licensing of a similar product.

Information that reveals cost or price infonnation, production capacities, budget levels or commercial strategies of NAC, its customers, or its suppliers.

d. Information that reveals aspects of past, present or future NAC customer-funded development plans and programs of potential commercial value to NAC.
e. Information that discloses patentable subject matter for which it may be desirable to obtain patent protection.

NAC INTERNATIONAL AFFIDAVIT PURSUANT TO 10 CFR 2.390 The information that is sought to be withheld is considered tb be proprietary for the reasons set foith in Items 4.a, 4.b, and 4.d.

5. The information to be withheld is being transmitted to the NRC in confidence.
6. The information sought to be withheld, including that compiled from many sources, is of a sort customarily held in confidence by NAC, and is, in fact, so held. This information has, to the best of my knowledge and belief, consistently been held in confidence by NAC. No public disclosure has been made, and it is not available in public sources. All disclosures to third parties, including any required transmittals to the NRC, have been made, or must be made, pursuant to regulatory provisions or proprietary agreements, which provide for lllaintenance of the information in confidence. Its initial designation as proprietary information and the subsequent steps taken to prevent its unauthorized disclosure are as set forth in Items 7 and 8 following.
7. Initial approval of proprietary treatment of a document/information is made by the Vice President, Engineering, the Project Manager, the Licensing Specialist, or the Director, Licensing

- the persons most likely to know the value and sensitivity of the information in relation to industry knowledge. Access to proprietary documents within NAC is limited via "controlled distribution" to individuals on a "need to know" basis. The procedure for external release of NAC proprietary documents typically requires the approval of the Project Manager based on a review of the documents for technical content, competitive effect and accuracy of the proprietary designation. Disclosures of proprietary documents outside of NAC are limited to regulato1y agencies, customers and potential customers and their agents, suppliers, 1.icensees and contractors with a legitimate need for the information, and then only in accordance with appropriate regulatory provisions or proprietary agreements.

8. NAC has invested a significant amount of time and money in the research, development, engineering and analytical costs to develop the information that is sought to be withheld as proprietary. This information is considered to be proprietary because it contains detailed descriptions of analytical approaches, methodologies, technical data and/or evaluation results not available elsewhere. The precise value of the expertise required to develop the proprietary information is difficult to quantify, but it is clearly substantial.
9. Public disclosure of the information to be withheld is likely to cause substantial harm to the competitive position of NAC, as the owner of the information, and reduce or eliminate the availability of profit-making opportunities. The proprietary information is part of NAC's comprehensive spent fuel storage and transport technology base, and its commercial value extends beyond the original development cost to include the development of the expertise to .

detennine and apply the appropriate evaluation process. The value of this proprietl'l.ry information and the competitive advantage that it provides to NAC would be lost if the infonnation were disclosed to the public. Making such information available to other parties, including competitors, without their having to make similar investments of time, labor and money would provide competitors with an unfair advantage and deprive NAC of the opportunity to seek an adequate return on its large investment.

NAC INTERNATIONAL AFFIDAVIT PURSUANT TO 10 CFR 2.390 State of Georgia, County of Gwinnett Mr. George Carver, being duly sworn, deposes and says:

That he has read the foregoing affidavit and the matters stated herein are true and correct to the best of his knowledge, information and belief.

Exe::ZComers, Georgia, fl1is 1+A. .day of _ga.lUC~ , 2020.

~>

George Carver Vice President, Engineering and Licensing NAC International Subscribed and sworn before me this 7th day of (jOJ1Ua.l0:( , 2020.

Serial No.: 19-492 ENCLOSURE 4 Exemption Request Need and Justification Kewaunee Power Station Dominion Energy Kewaunee, Inc. (DEK)

Serial No.: 19-492 Enclosure 4 Page 1 of 11 Table of Contents Executive Summary .... ..... .... .. ... ... ... ........ .. ..... .. ............ .. ........... .. .... .. ........ ..... .. ... .... ..... 2 1.0 Background ............. ..................................................... ......................................... 3 1.1 Charpy V-notch Impact Testing Requirements............................................. 3 1.2 Post-Heat Treatment Ultrasonic Examination (UT) Requirements . . . ........... 3 2.0 Requested Exemption ........ .. .... .... .......... .... ............ .. ........ .... .... ............ ...... .......... 3 3.0 Technical Assessment . . . ...................................................................................... 4 3.1 Charpy V-notch Impact Testing Exemption Request Justification ................ 4 3.2 Post-Heat Treatment Ultrasonic Examination (UT) Exemption Request Justification.................................................................................................... 4 4.0 Basis for Approval ... ...... ............... .... ........... .. ....... .... ... ........... ..... ... .......... ... ....... ... 4 4.1 Authorized by Law ........................................................................................ 5 4.2 Does Not Endanger Life, Property or Common Defense and Security .. ..... .. 5 4.3 Otherwise in The Public Interest - Alternatives............................................. 5 4.4 Conclusion .................................................................................................... 5 5.0 Environmental Consideration ........................................................ ........................ 6 5.1 Background .. ........ .... ... ..... .... ........ .. .. ..... ......... ......... ... ....... ..... .. .... .. ... ......... ... 6 5.2 No Significant Hazards Consideration ............ :........ :.................................... 6 5.3 Environmental Impact of the Proposed Action ....... ............. ........ ... .... ........... 8 5.4 Environmental Impact of Alternatives to the Proposed Action ....................... 9 5.5 Conclusion ..................................................................................................... 9 6.0 References ...................................................... :..................................................... 9

Serial No.: 19-492 Enclosure 4 Page 2 of 11 Exemption Request for Nonconforming Transportable Storage Canisters (TSCs)

Executive Summary NAC International, the Certificate of Compliance (CoC) holder for the MAGNASTOR storage system, recently notified DEK that they had identified two compliance issues related to the fabrication of several transportable storage canisters (TSCs) delivered to DEK.

The first issue was identified during a review of Certified Material Test Reports (CMTRs) for a current NAC project. NAC noted that certain components of the spent fuel basket were not impact tested in accordance with NAC's fabrication specification and purchase orders. These fabrication specifications and purchase orders reflect the requirements detailed in the CoC, which requires the spent fuel baskets, in part, to be designed, material procured, fabricated and tested in accordance with the requirements of the ASME Code, Section Ill, 2001/2003, Subsection NG, minus any Code exceptions previously approved by the NRC. Specifically, Article NG-2322.2(a)(4) requires Charpy V-notch impact specimens for carbon steel plate material greater than% inches th_ick to be oriented in a direction normal to the principal rolling direction during the test. NAC identified that some impact tests were performed incorrectly (i.e., the test specimens were impact tested in the longitudinal direction). NAC entered this into their Corrective Action Program (CAP) as Corrective Action Report (CAR) 19-01.

After NAC identified the impact testing issue, they engaged their suppliers. Upon this action, existing relevant suppliers began to perform their own internal reviews. At this point Hitachi Zosen (HZ), an impact testing affected supplier, further identified plate material greater than 0. 750 inches thick that had been procured from Kobe Steel was not being ultrasonically examined (UT) after heat treatment. This second issue was entere.d into NAC's CAP as CAR 19-02 and a stop work order was placed on HZ until their internal reviews were complete and accepted by NAC. As previously described, the MAGNASTOR spent fuel baskets are to be designed, material procured, fabricated and tested in accordance with the ASME Code, Section Ill, Subsection NG, minus any Code exceptions previously approved by the NRC. Specifically, Article NG-2500, NG-2531, and NG-2532 require a post heat-treatment UT for carbon steel plate material greater than %

inches thick. HZ identified ttiat Kobe Steel was performing UT prior to heat treatment.

This heat treatment was a normalization of the base material. In this process, the material is elevated in temperature and then allowed to naturally cool in an ambient environment.

NAC has performed a detailed review of these two issues . and has completed their technical evaluations. NAC has determined that these two issues do not present a safety issue since all affected hardware will perform its intended safety functions. However, the

Serial No.: 19-492 Enclosure 4 Page 3 of 11 MAGNASTOR CoC requires DEK to implement the MAGNASTOR system in accordance with the CoC. Thus, DEK is requesting NRC approval of an exemption request to 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 72.212(b)(11), and 10 CFR 72.214 because these non-conformances affect previously loaded TSCs that are currently in storage operations.

1.0 Background

DEK currently has 24 MAGNASTOR systems in storage operations that are not in compliance with the Code requirements for Charpy V-notch impact testing and post-heat treatment UT requirements. Enclosure 1 lists the affected TSCs.

MAGNASTOR CoC, Appendix A, Section 4.2, states that the ASME Code, 2001 Edition with Addenda through 2003, Section Ill, Subsection NG, is the governing Code for the design, material procurement, fabrication and testing of the spent fuel baskets, minus any Code exception detailed in Section 4.2.1.

1.1 Charpy V-notch Impact Testing Requirements ASME Code, Section Ill, 2001/2003, Subsection NG, Article NG-2322.2(a)(4) requires Charpy V-notch impact specimens for carbon steel plate material greater than % inches thick to be oriented in a direction normal to the principal rolling direction during the test.

1.2 Post-Heat Treatment Ultrasonic Examination (UT) Requirements ASME Code, Section Ill, Subsection NG, Articles NG-2500, NG-2531, and NG-2532 require a post heat-treatment UT for carbon steel plate material greater than % inches thick.

2.0 Requested Exemption In accordance with 10 CFR 72.7, "Specific Exemptions," DEK requests NRC approval of an exemption for the DEK Independent Spent Fuel Storage Installation (ISFSI) from the following requirements of 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(11), and 10 CFR 72.214 due to two non-compliance issues with Appendix A, Section 4.2 of CoC No. 1031, Amendment 6:

  • 10 CFR 72.212(a)(2), which states "[t]his general license is limited to storage of spent fuel in casks approved under the provisions of this part."

Serial No.: 19-492

  • Enclosure 4 Page 4 of 11
  • 10 CFR 72.212(b)(3), which states the general licensee must "[e]nsure that each cask used by the general licensee conforms to the terms, conditions, and specifications of a CoC or an amended CoC listed in § 72.214."
  • 10 CFR 72.212(b)(5)(i), which states [t]he cask, once loaded with spent fuel or once the changes authorized by an amended CoC have been applied, will conform to the terms,* conditions, and specifications of a CoC or an amended Coe listed in§ 72.214."
  • The portion of 10 CFR 72.212(b)(11) which states that "[t]he licensee shall comply with the terms, conditions, and specifications of the CoC ... "
  • 10 CFR 72.214, which states the "[l]ist of approved spent fuel storage casks."

A list of affected TSCs and their serial numbers is provided in Enclosure 1.

Enclosures 2 and 3 list the affected spent fuel basket sub-components for impact testing and post-heat treatment UT, respectively. These systems and components are currently loaded and in storage operations on the ISFSI pad. This exemption request would allow the continued use of these loaded systems for the term specified in the CoC. This exemption request does not apply to 10 CFR Part 71 transportation designs and applications. NAG has submitted a separate request to revise the associated transportation certificate (i.e., MAGNATRAN) to support these Code exceptions. This exemption request concludes, along with supporting technical documentation from NAG, that the affected systems and components still maintain their ability to perform their safety functions.

3.0 Technical Assessment The proposed exemption is limited in scope to only those affected TSCs listed in Enclosure 1 and relates to ASME Code compliance with material procurement of carbon steel plate material for the MAGNASTOR spent fuel baskets. Specifically, Charpy V-notch impact testing and post-heat treatment UT for carbon steel plate of specific thicknesses.

3.1 Charpy V-notch Impact Testing Exemption Request Justification NAC's CAP generated CAR 19-01 to assess Charpy V-notch testing of A537 and A517 materials in both the longitudinal and transverse directions. This assessment was documented by NAG International in 71160-WP-020, Revision 2. This document concludes that the materials confined to the extent of condition review demonstrate adequate fracture toughness requirements

Serial No.: 19-492 Enclosure 4 Page 5 of 11 when scaled to the approximate transverse specimen orientation, in conjunction with the material's relative susceptibility to brittle fracture. This document is provided in Enclosure 5 as justification for granting DEK an exemption request for this issue.

3.2 Post-Heat Treatment Ultrasonic Examination (UT) Exemption Request Justification NAC's CAP generated CAR 19-02 to assess the history of the ASME Code requirement for post-heat treatment UT and whether it was intended to apply to a normalization. NAC has requested a re-examination of existing procured material, which had a UT performed prior to being normalized. All material that was re-examined passed its UT, and when compared to the pre-normalization UT results no indications were identified. In addition, NAC consulted with an ASME Code expert for input on whether a UT is necessary after normalization.

The Code expert's input was that normalization would not result in the creation of any indications in the material, which aligns with the re-examination UT results. This Code expert's letter to NAC is provided in Enclosure 6 as justification for granting DEK an exemption request for this issue.

4.0 Basis for Approval The proposed exemption request is limited in scope in that it only relates to compliance with certain material testing and examination requirements specified in the ASME Code, as invoked by the MAGNASTOR CoC. The proposed exemption request involves no physical change to the spent fuel basket design, and no change to the basket materials.

The Technical Assessment (Section 3.0) provides the basis for the conclusion that there is reasonable assurance that safety margin exists for the affected TSCs, listed in Enclosure 1, for their initial 20-year service lifetime, even though 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(11) and 10 CFR 72.214 are not explicitly met. Thus, the requested exemption is authorized by law since it does not endanger life, property, or common defense and*

security and is otherwise in the public interest as described below.

4.1 Authorized by Law DEK is requesting an exemption from the requirements of 10 CFR 72.212(a)(2),

10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(11), and 10 CFR 72.214. 10 CFR 72.7 gives the NRC the authority to grant exemptions

Serial No.: 19-492 Enclosure 4 Page 6 of 11 from the requirements of 10 CFR Part 72 provided they do not endanger life or property or the common defense and security and are otherwise in the public interest. This exemption request documents that these criteria are met. The exemption is authorized by law.

4.2 Does Not Endanger Life, Property or Common Defense and Security A discussed in Section 3.0, the affected TSCs listed in Enclosure 1 can still perform their intended safety function. Even though the Charpy V-notch test specimens were not in the orientation required by the ASME Code, sufficient evidence exists to reasonably conclude that had they been tested in the transverse direction they would have met the Code acceptance requirements.

If the plate material that had UT performed prior to normalization been examined after normalization, sufficient evidence exists to reasonably conclude that the UT results would have been the same as those observed prior to normalization.

4.3 Otherwise In The Public Interest - Alternatives DEK has evaluated replacement of the non-conforming materials as an alternative to the proposed exemption request. However, the replacement alternative does not provide the safety assurances and reduced radiological risk provided by the exemption request. To bring the affected TSCs into compliance with CoC 1031, Amendment 6 would involve -an infrequent and high-risk series of actions. This includes removing the TSC from the concrete overpack, opening the TSC, removing the fuel, reloading it into a TSC with a fuel basket that is in compliance, and returning the system into storage operations. The necessary equipment, personnel, facilities, time, and radiological exposure required to perform these actions is not considered to be in the interest of the public or personnel/radiological safety.

4.4 Conclusion Based on the above discussion, the exemption request is authorized by law and will not endanger life or property or the common defense and security and is otherwise in the public interest as the least risk, least dose, least radioactive waste and least cost option. Any campaign to discard and replace the affected TSCs would create operational challenges and risks associated with additional operational requirements, occupational doses, and generation of radioactive wastes.

Serial No.: 19-492 Enclosure 4 Page 7 of 11 5.0 Environmental Consideration 5.1 Background MAGNASTOR storage casks are designed to mitigate the effects of design basis accidents that could occur during storage. Design basis accidents account for human-induced events and the most severe natural phenomena reported for the site and surrounding area. Postulated accidents analyzed for an ISFSI include tornado winds and tornado-generated missiles, a design basis

  • earthquake, a design basis flood, an accidental cask drop, lightning effects, fire, explosions, and other incidents.

Considering the specific design requirements for each accident condition, the design of the cask would prevent loss of confinement, shielding, and criticality control. Without the loss of confinement, shielding, or criticality control functions, the risk to public health and safety is not compromised. The NRC staff performed a detailed safety evaluation of the CoC amendment under which the subject 24 canisters were loaded (i.e., Amendment 6) and found that an acceptable safety margin was maintained, that there was reasonable assurance that the spent fuel could be stored safely, that the acceptance criteria specified in 10 CFR Part 72 were met, and that there continued to be reasonable assurance that public health and safety will be adequately

  • protected.

5.2 No Significant Hazards Consideration In order to support the assertion in Section 5.3 that this exemption request meets the definition of a regulatory action eligible for a categorical exclusion or otherwise does not require an environmental review, DEK is providing the following No Significant Hazards Consideration (NSHC). The NSHC is

. perfo~med in accordance with 10 CFR 50.92, insofar as 10 CFR 72 does not establish separate criteria. DEK has evaluated the proposed exemption request in accordance with the standards in 10 CFR 50.92 and has determined that the requested exemption presents no significant hazards. DEK evaluation against each of the criteria in 10 CFR 50.92 follows.

1.
  • Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

The probability (frequency of occurrence) of any Updated Final Safety Analysis Report (UFSAR) evaluated accident occurring is not affected by

Serial No.: 19-492 Enclosure 4 Page 8 of 11 the requested exemption, because DEK continues to comply with the design basis criteria established for TSCs.

There is no change to the consequences of postulated accidents. The enclosed supporting technical justifications demonstrate that the affected TSCs and subcomponents of the spent fuel baskets will continue to perform their intended safety function. Thus, the results of accident evaluations remain within the NRG approved acceptance limits.

Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The exemption request does not create the possibility of a new operating mode, or accident scenario, nor does the exemption request rely on new equipment, or postulate a new equipment failure mode. In order for an activity to create the possibility for an accident of a different type, the activity would have to introduce a new material, a new man-machine interface, a new operational process, or other significant change that would initiate a new type of failure or cause a previously-described accident to propagate differently. As previously described, the proposed activity is purely an ASME Code material procurement testing and examination compliance issue and involves no physical change to the spent fuel basket design, and no changes to the spent fuel basket materials or.the loading operations. Therefore, the proposed activity does not create a possibility for an accident of a different type and does not result in more than a minimal increase in the likelihood of occurrence of a malfunction- of an SSC important to safety previously evaluated in the UFSAR.

Serial No.: 19-492 Enclosure 4 Page 9 of 11

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

As discussed in Section 3.0, sufficient evidence exists to reasonably demonstrate that had the Charpy V-notch test specimens been tested in the correct orientation, they would have met the applicable ASME Code acceptance requirements. Thus, the material has been demonstrated to have the required fracture toughness. In addition, sufficient evidence exists to demonstrate the UT results prior to normalization are indicative of the results that would have been observed had the UT been performed post-normalization. Therefore, the proposed exemption request does not involve a significant reduction in a margin of safety.

Based on the considerations above, DEK has determined that storage of spent fuel in the affected TSCs listed in Enclosure 1, in accordance with the exemption request, does not involve a significant hazards consideration as defined in 10 CFR 50.92(c), in that it does not: (1) involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety.

5.3 Environmental Impact of the Proposed Action Based on the technical review provided in Section 3.0, the affected TSCs and sub-components will continue to perform their intended safety functions. Thus, there is no environmental impact from the proposed action. The proposed action would restore the affected TSCs to a conforming and operable status, allowing them to remain in storage operations for the term specified in the CoC.

The exemption request provides the bases for acceptability of the affected TSCs.

The exemption request meets the categorical exclusion of 10 CFR 51.22(c)(25) as a regulatory action eligible for a categorical exclusion or otherwise does not require an environmental review, because there is: (Note: DEK responses are provided in brackets after each requirement)

(i) No significant hazards consideration;

[See Section 5.2.]

Serial No.: 19-492 Enclosure 4 Page 10 of 11 (ii) No significant change in the types or significant increase in the amounts of any effluents that may be released offsite;

[No significant changes to effluent types or amounts are expected as a result of this exemption request.]

(iii) No significant increase in individual or cumulative public or occupational radiation exposure;

[No significant increases in radiation to individuals or the public are requested under this exemption request.]

(iv) No significant construction impact;

[No construction is being requested or impacted as a result of this exemption request.]

(v) No significant increase in the potential for or* consequences from radiological accidents; and

[No significant increase in the potential for or consequences of a radiological accident is expected as a result of this exemption request.]

(vi) The requirements from which an exemption is sought involve: ...

(C) Inspection or surveillance requirements; ...

[The exemption request seeks an exemption from CoC, Appendix A, Section 4.2, which invokes ASME Code, Section Ill, Subsection NG requirements for Charpy V-notch impact testing and post-heat treatment UT examination requirements.]

The proposed exemption does not require any changes to the DEK ISFSI Environmental Report and applicable Safety Analysis Report analyses remain bounding.

5.4 Environmental Impact of Alternatives to the Proposed Action As discussed in Section 4.3, DEK has considered alternatives to the proposed exemption, which is to unload the affected TSCs, discard, and replace them.

The environmental impacts of this alternative would result in both real and potential environmental impacts. DEK has estimated that the implementation of these alternatives would result in a significant amount of occupational dose and low-level radioactive waste (LLRW) that would have to be processed and disposed.

)

Serial No.: 19-492 Enclosure 4 Page 11 of 11 Replacement of the TSC would involve significant dose and radioactive waste concerns. Occupational doses would be significant as grinding and welding activities would need to be performed in the vicinity of spent nuclear fuel. In addition, each discarded TSC would become radioactive waste. Additional radioactive waste would be generated from the TSC opening operations performed to remove the welds from the existing TSC. Other radioactive wastes would be generated from radioactively contaminated consumables and anticontamination clothing used during the unloading and reloading process.

This radioactive waste would be transported and ultimately disposed of at a qualified LLRW disposal facility.

In addition, this evolution could result in additional risks of both off-normal events and design basis accidents, such as a fuel handling or cask drop events, both of which could involve a radiological release to the environment.

5.5 Conclusion As a result of the environmental assessment, DEK concludes that the proposed exemption, which will allow DEK to maintain affected TSCs in their current state with non-compliant Charpy V-notch testing and post-heat treatment UT, is in the public interest because it avoids the adverse environmental effects associated with the alternatives to the proposed action.

6.0 References

1. MAGNASTOR Final Safety Analysis Report, Revision 10
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