ML18029A648
| ML18029A648 | |
| Person / Time | |
|---|---|
| Site: | NuScale |
| Issue date: | 01/29/2018 |
| From: | NRC |
| To: | NRC/NRO/DNRL/LB1 |
| References | |
| Download: ML18029A648 (3) | |
Text
NuScaleDCRaisPEm Resource From: Cranston, Gregory Sent: Monday, January 29, 2018 1:27 PM To: RAI@nuscalepower.com Cc: NuScaleDCRaisPEm Resource; Lee, Samuel; Chowdhury, Prosanta; Jackson, Diane; Travis, Boyce; Tabatabai, Omid
Subject:
Request for Additional Information No. 357 RAI No. 9235 (6.2.1)
Attachments: Request for Additional Information No. 357 (eRAI No. 9235).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.
The NRC Staff recognizes that NuScale has preliminarily identified that the response to one or more questions in this RAI is likely to require greater than 60 days. NuScale is expected to provide a schedule for the RAI response by email within 14 days.
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: 388 Mail Envelope Properties (CY4PR09MB12874925262F49BC8795198790E50)
Subject:
Request for Additional Information No. 357 RAI No. 9235 (6.2.1)
Sent Date: 1/29/2018 1:27:01 PM Received Date: 1/29/2018 1:27:05 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 "Jackson, Diane" <Diane.Jackson@nrc.gov>
Tracking Status: None "Travis, Boyce" <Boyce.Travis@nrc.gov>
Tracking Status: None "Tabatabai, Omid" <Omid.Tabatabai-Yazdi@nrc.gov>
Tracking Status: None "RAI@nuscalepower.com" <RAI@nuscalepower.com>
Tracking Status: None Post Office: CY4PR09MB1287.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 817 1/29/2018 1:27:05 PM Request for Additional Information No. 357 (eRAI No. 9235).pdf 91760 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
Recipients Received:
Request for Additional Information No. 357 (eRAI No. 9235)
Issue Date: 01/29/2018 Application
Title:
NuScale Standard Design Certification 048 Operating Company: NuScale Power, LLC Docket No.52-048 Review Section: 06.02.01 - Containment Functional Design Application Section: 6.2.1 QUESTIONS 06.02.01-5 Appendix A to 10 CFR Part 50, General Design Criteria (GDC) 4, Environmental and dynamic effects design bases, requires that SSCs important to safety shall be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents (LOCAs).
GDC 39, Inspection of containment heat removal system, requires, in part, that the containment heat removal system shall be designed to permit appropriate periodic inspection of important components to assure the integrity and capability of the system.
GDC 53, Provisions for containment testing and inspection, requires, in part, that the reactor containment shall be designed to permit appropriate periodic inspection of all important areas.
Follow-up RAI No 8910, Question 06.02.02-2 In a letter dated August 16, 2017, NuScale responded to staff RAI No. 8910, Question 06.02.02-2, which requested NuScale to provide programmatic assurance that establishes the requirement to perform periodic inspections of the containment vessel (CNV) heat removal surfaces.
NuScale revised FSAR Section 6.2 and Table 6.2-3, Containment Vessel Inspection Elements, by adding the following inspection element:
Component Description Examination Category Examination Method Notes CNV Shell CNV inner and outer shell General Visual Inspection pursuant to GDC 39 The staff notes that ASME BPVC,Section XI, does not have a General examination category. Instead, ASME BPVC,Section XI, Table IWE-2500-1 (E-A), Examination Category E-A, Containment Surfaces, would be an appropriate examination category for the CNV inner and outer shells. Furthermore, listing the examination method as visual is not clear as ASME BPVC,Section XI, Table IWE-2500-1 (E-A) lists both general visual and VT-3 examinations.
Based on the part descriptions in ASME BPVC,Section XI, Table IWE-2500-1 (E-A), a general visual examination would be for applicable to the CNV inner shell as it is not wetted during normal operation. However, the outer CNV shell is constantly wetted due to its location in the ultimate heat sink. Degradation of the CNV cladding could impact the structural integrity of the CNV low alloy steel base metal by allowing borated water from the ultimate heat sink to contact the base metal. A general visual examination would not provide reasonable assurance to detect signs of corrosion of the low alloy steel. ASME BPVC,Section XI, Table IWE-2500-1 (E-A), lists Item Number E1.12 for Wetted Surfaces of Submerged Areas. The examination requirement is a VT-3.
Accordingly, the staff requests that NuScale:
- Revise DCD Tier 2, FSAR, Table 6.2-3 to state that the examination method for the CNV outer shell will be a VT-3 in accordance with ASME BPVC,Section XI, Table IWE-2500-1 (E-A), Item Number E1.12.
- Revise DCD Tier 2, FSAR, Table 6.2-3 to state that the examination method for the CNV inner shell will be a general visual in accordance with ASME BPVC,Section XI, Table IWE-2500-1 (E-A), Item Number E1.10.
- Revise DCD Tier 2, FSAR, Table 6.2-3 to state that the examination categories for both the CNV inner and outer shells will be in E-A in accordance with ASME BVPC,Section XI, Table IWE-2500-1.Revise DCD Tier 2, FSAR, Table 6.2-3 to state that the examination categories for both the CNV inner and outer shells will be in E-A in accordance with ASME BVPC,Section XI, Table IWE-2500-1.