ML18002A530
| ML18002A530 | |
| Person / Time | |
|---|---|
| Site: | NuScale |
| Issue date: | 01/02/2018 |
| From: | NRC |
| To: | NRC/NRO/DNRL/LB1 |
| References | |
| Download: ML18002A530 (4) | |
Text
NuScaleDCRaisPEm Resource From: Cranston, Gregory Sent: Tuesday, January 02, 2018 4:03 PM To: RAI@nuscalepower.com Cc: NuScaleDCRaisPEm Resource; Lee, Samuel; Chowdhury, Prosanta; Karas, Rebecca; Schmidt, Jeffrey; Burja, Alexandra; Markley, Anthony
Subject:
Request for Additional Information No. 316 RAI No. 9222 (9.1.1)
Attachments: Request for Additional Information No. 316 (eRAI No. 9222).pdf Attached please find NRC staffs request for additional information concerning review of the NuScale Design Certification Application.
Please submit your technically correct and complete response within 60 days of the date of this RAI to the NRC Document Control Desk.
If you have any questions, please contact me.
Thank you.
Gregory Cranston, Senior Project Manager Licensing Branch 1 (NuScale)
Division of New Reactor Licensing Office of New Reactors U.S. Nuclear Regulatory Commission 301-415-0546 1
Hearing Identifier: NuScale_SMR_DC_RAI_Public Email Number: 343 Mail Envelope Properties (MWHPR09MB1200FA6D35338784D5E62AA590190)
Subject:
Request for Additional Information No. 316 RAI No. 9222 (9.1.1)
Sent Date: 1/2/2018 4:03:14 PM Received Date: 1/2/2018 4:03:23 PM From: Cranston, Gregory Created By: Gregory.Cranston@nrc.gov Recipients:
"NuScaleDCRaisPEm Resource" <NuScaleDCRaisPEm.Resource@nrc.gov>
Tracking Status: None "Lee, Samuel" <Samuel.Lee@nrc.gov>
Tracking Status: None "Chowdhury, Prosanta" <Prosanta.Chowdhury@nrc.gov>
Tracking Status: None "Karas, Rebecca" <Rebecca.Karas@nrc.gov>
Tracking Status: None "Schmidt, Jeffrey" <Jeffrey.Schmidt2@nrc.gov>
Tracking Status: None "Burja, Alexandra" <Alexandra.Burja@nrc.gov>
Tracking Status: None "Markley, Anthony" <Anthony.Markley@nrc.gov>
Tracking Status: None "RAI@nuscalepower.com" <RAI@nuscalepower.com>
Tracking Status: None Post Office: MWHPR09MB1200.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 556 1/2/2018 4:03:23 PM Request for Additional Information No. 316 (eRAI No. 9222).pdf 90372 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
Recipients Received:
Request for Additional Information No. 316 (eRAI No. 9222)
Issue Date: 01/02/2018 Application Title: NuScale Standard Design Certification 048 Operating Company: NuScale Power, LLC Docket No.52-048 Review Section: 09.01.01 - Criticality Safety of Fresh and Spent Fuel Storage and Handling Application Section: 9.1.1 QUESTIONS 09.01.01-19 Title 10 of the Code of Federal Regulations (10 CFR), Section 50.68, Criticality accident requirements, provides the regulatory requirements for maintaining subcriticality in the spent fuel pool. General Design Criterion (GDC) 61, Fuel storage and handling and radioactivity control, in Appendix A to 10 CFR Part 50, requires, in part, that the fuel storage and handling systems shall be designed to assure adequate safety under normal and postulated accident conditions, including a capability to permit appropriate periodic inspection and testing of components important to safety. The applicant has chosen to incorporate neutron absorbing material into the design of the spent fuel racks to maintain subcriticality and to assure adequate safety. To meet GDC 61, Standard Review Plan (SRP) Section 9.1.2, New and Spent Fuel Storage, specifies that provisions for inspection and testing are necessary to verify that there is no degradation of any strong fixed neutron absorbers. Furthermore, 10 CFR 50.36, Technical specifications, requires an applicant or licensee to establish administrative controls in the technical specifications (TS) that will assure operation of the facility in a safe manner.
TS 5.5.12, part (a) states that the spent fuel storage rack neutron absorber monitoring program shall include periodic physical examination or neutron attenuation testing; however, the coupon monitoring program description in technical report TR-0816-49833-P, Fuel Storage Rack Analysis, Revision 0, specifies that at least one coupon shall be removed at specified intervals to be measured, visually examined, and to undergo boron-10 (10B) areal density measurement. Therefore, TS 5.5.12, part (a) must include periodic physical examination and neutron attenuation testing.
Furthermore, the phrase provide the credited criticality control in parts (a) and (c) of TS 5.5.12 is too vague to constitute an acceptance criterion to ensure the safety function of the neutron absorbing material is maintained, which leaves questions as to how compliance with 10 CFR 50.68 will be ensured. The staff requests more specific acceptance criteria that will ensure the acceptability of the measured 10B areal density, as it is a key assumption in the criticality analysis. The applicants technical report TR-0816-49833-P, Section 3.4.1.3.4 already defines the acceptance criteria for 10B areal density coupon measurements.
Finally, part (b) of TS 5.5.12 calls for establishment of performance-based frequencies for examination or testing based on observed trends or calculated projections of neutron absorber degradation, not to exceed 10 years. However, the applicant has not specified the neutron absorbing material to be used, and as such, there is uncertainty in how the material will behave while in service. In technical report TR-0816-49833-P, Section 3.4.1.3.4 already defines the sampling schedule for the neutron coupon monitoring program. A 10-year inspection interval is not consistent with the sampling schedule. TS 5.5.12 part (b) should be revised to reflect the licensing basis described in TR-0816-49833-P.
Therefore, please revise TS 5.5.12 as follows:
- a. Update TS 5.5.12 part (a) to include periodic physical examination and neutron attenuation testing.
- b. Provide specific acceptance criteria for the neutron absorber measured 10B areal density.
- c. Update the sampling intervals in accordance with TR-0816-49833-P.