ML19067A143
| ML19067A143 | |
| Person / Time | |
|---|---|
| Site: | NuScale |
| Issue date: | 03/20/2019 |
| From: | Amadiz Marieliz Vera NRC/NRO/DLSE/LB1 |
| To: | Samson Lee NRC/NRO/DLSE/LB1 |
| Vera A M/nro/415-5861 | |
| References | |
| Download: ML19067A143 (9) | |
Text
March 20, 2019 MEMORANDUM TO:
Samuel S. Lee, Chief Licensing Branch 1 Division of Licensing, Siting, and Environmental Analysis Office of New Reactors FROM:
Marieliz Vera, Project Manager /RA/
Licensing Branch 1 Division of Licensing, Siting, and Environmental Analysis Office of New Reactors
SUBJECT:
PLAN FOR REGULATORY AUDIT OF NUSCALE POWER, LLC, EMERGENCY CORE COOLING SYSTEM VALVE DESIGN DEMONSTRATION TESTING AND FOLLOW-UP ITEMS On January 6, 2017, NuScale Power, LLC (NuScale) submitted a design certification application (DCA) for a small modular reactor to the U.S. Nuclear Regulatory Commission (NRC)
(Agencywide Documents Access and Management System Accession No. ML17013A229).
The NRC staff initiated its detailed technical review of NuScales DCA on March 15, 2017.
The purpose of the subject audit to be conducted by the NRC staff is to review the design of the emergency core cooling system (ECCS) valves for the NuScale reactor, including the design demonstration testing and other follow-up items from an audit conducted in 2018.
The audit will review information located at the NuScale Office in Rockville, Maryland; in the NuScale electronic reading room; and at the ECCS valve vendor facility. The audit is currently scheduled to begin on March 20, 2019, and end on July 25, 2019. The audit plan is enclosed.
Docket No.52-048
Enclosure:
As stated cc w/encl.: DC NuScale Power, LLC Listserv CONTACT: Marieliz Vera, NRO/DLSE 301-415-5861
ML19067A143 NRO-002 OFFICE NRO/DLSE/LB1/PM NRO/DLSE/LB1/LA NRO/DEI/MEB/BC NAME MVera CSmith(SGreen for)
MVera DATE 03/08/2019 03/20/2019 03/20/2019
U.S. NUCLEAR REGULATORY COMMISSION PLAN FOR REGULATORY AUDIT OF NUSCALE POWER, LLC, EMERGENCY CORE COOLING SYSTEM VALVE DESIGN DEMONSTRATION TESTING AND FOLLOW-UP ITEMS NUSCALE POWER, LLC STANDARD PLANT DESIGN CERTIFICATION DOCKET NO.52-048 AUDIT PLAN APPLICANT:
NuScale Power, LLC (NuScale)
APPLICANT CONTACT:
Marty Bryan, NuScale DURATION:
March 20 to July 25, 2019 LOCATION:
U.S. Nuclear Regulatory Commission (NRC) Headquarters 11545 Rockville Pike Rockville, MD 20852-2738 NuScale Rockville Office NuScale Electronic Reading Room (eRR)
ECCS Valve Vendor Facility AUDIT TEAM:
Thomas G. Scarbrough, Senior Mechanical Engineer (NRC),
Audit Lead Shanlai Lu, Senior Reactor Systems Engineer (NRC)
Ian Jung, Senior Reliability and Risk Analyst (NRC)
John Budzynski, Reactor Systems Engineer (NRC)
Clinton Ashley, Reactor Systems Engineer (NRC)
Alissa Neuhausen, Structural Engineer (NRC)
Marieliz Vera, Project Manager (NRC)
I.
BACKGROUND On January 6, 2017, NuScale Power, LLC (NuScale) submitted a design certification application (DCA) with subsequent revisions (Reference 1) for a small modular reactor (SMR) to the U.S.
Nuclear Regulatory Commission (NRC) (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17013A229). On March 15, 2017, the NRC accepted the DCA for docketing to initiate the NRC review of the NuScale SMR design (Reference 2).
Enclosure
2 The NRC staff determined that efficiency gains would be realized by auditing documents supporting the NuScale SMR design presented in the NuScale DCA Part 2 in lieu of multiple requests for additional information (RAIs) for the applicant to submit design documents.
In late 2017 and early 2018, the NRC staff conducted an initial audit of the NuScale documentation supporting the NuScale DCA regarding the design of the emergency core cooling system (ECCS) valves to be used in the NuScale SMR. The NRC staff prepared a report summarizing the results of the initial audit of the NuScale ECCS valve design (Reference 3). In 2018, the NRC staff conducted an audit to review the Failure Modes and Effects Analysis (FMEA) and additional information at the valve vendor related to the design of the ECCS valves to be used in the NuScale SMR. The NRC staff prepared a report summarizing the results of the ECCS valve FMEA audit (Reference 4).
II.
PURPOSE The purpose of this audit is to evaluate the ECCS valve design demonstration testing, including test plans, procurement requirements, set-up and performance specifications, procedures, acceptance criteria, quality assurance (QA) provisions and implementation, equipment and instrumentation descriptions, calibration information, and results and evaluation. The audit will include review of the measured pressure transient history for potential water hammer. In addition, the NRC staff will evaluate the resolution of the follow-up items from the ECCS valve FMEA audit conducted in 2018. Among the most significant remaining items for the demonstration of the safety features of the ECCS valves and their individual subcomponents to satisfy the NRC regulations are the following:
(1) capability of the main valve to open fully in a timely manner for design-basis conditions when required; (2) assurance that the main valve will not partially or fully open prematurely; (3) capability of the inadvertent actuation block (IAB) valve to close and seal the vent line in a timely manner at the initial opening of the trip valve to prevent the main valve from opening partially or fully until the differential pressure between the reactor pressure vessel (RPV) and containment vessel (CNV) has reduced sufficiently to the specified conditions; (4) capability of the IAB valve to open in a timely manner when the differential pressure between the RPV and CNV has reduced sufficiently to the specified conditions to allow the main valve to open fully to initiate emergency core cooling within the time specified in accident analyses; (5) assurance that the trip valve and line size, orifices, fittings, and installed configuration will vent the trip line adequately in a timely manner to allow the differential pressure between the RPV and CNV to close and seal the IAB valve against the force of the IAB spring to prevent the main valve from opening partially or fully (with consideration of hot borated water flashing to steam and boron deposits) until the differential pressure between the RPV and CNV has reduced sufficiently to the specified conditions; and (6) assurance that the trip valve and line size, orifices, fittings, and installed configuration will vent the trip line adequately in a timely manner after the IAB valve
3 has opened to vent the main valve control chamber (with consideration of hot borated water flashing to steam and boron deposits) to allow the main valve to fully open within its stroke-time requirements.
III.
REGULATORY AUDIT BASIS Title 10 of the Code of Federal Regulations (10 CFR) Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants, Section 47, Contents of Applications; Technical Information, states the following:
The application must contain a level of design information sufficient to enable the Commission to judge the applicants proposed means of assuring that construction conforms to the design and to reach a final conclusion on all safety questions associated with the design before the certification is granted. The information submitted for a design certification must include performance requirements and design information sufficiently detailed to permit the preparation of acceptance and inspection requirements by the NRC, and procurement specifications and construction and installation specifications by an applicant. The Commission will require, before design certification, that information normally contained in certain procurement specifications and construction and installation specifications be completed and available for audit if the information is necessary for the Commission to make its safety determination.
Paragraph (c) in 10 CFR 52.47 states the following specific requirements for applications that differ from the light-water reactor designs that have been licensed to date:
(c) This paragraph applies, according to its provisions, to particular applications:
(1) An application for certification of a nuclear power reactor design that is an evolutionary change from light-water reactor designs of plants that have been licensed and in commercial operation before April 18, 1989, must provide an essentially complete nuclear power plant design except for site-specific elements such as the service water intake structure and the ultimate heat sink; (2) An application for certification of a nuclear power reactor design that differs significantly from the light-water reactor designs described in paragraph (c)(1) of this section or uses simplified, inherent, passive, or other innovative means to accomplish its safety functions must provide an essentially complete nuclear power reactor design except for site-specific elements such as the service water intake structure and the ultimate heat sink, and must meet the requirements of 10 CFR 50.43(e); and (3) An application for certification of a modular nuclear power reactor design must describe and analyze the possible operating configurations of the reactor modules with common systems, interface requirements, and system interactions. The final safety analysis must also account for differences among the configurations, including any restrictions that will be necessary during the construction and startup of a given module to ensure the safe operation of any module already operating.
4 Paragraph (e) in 10 CFR 50.43, Additional standards and provisions affecting class 103 licenses and certifications for commercial power, required by 10 CFR 52.47(c)(2) states the following:
(e) Applications for a design certification, combined license, manufacturing license, or operating license that propose nuclear reactor designs which differ significantly from light-water reactor designs that were licensed before 1997, or use simplified, inherent, passive, or other innovative means to accomplish their safety functions, will be approved only if:
(1) (i) The performance of each safety feature of the design has been demonstrated through either analysis, appropriate test programs, experience, or a combination thereof; (ii) Interdependent effects among the safety features of the design are acceptable, as demonstrated by analysis, appropriate test programs, experience, or a combination thereof; and (iii) Sufficient data exist on the safety features of the design to assess the analytical tools used for safety analyses over a sufficient range of normal operating conditions, transient conditions, and specified accident sequences, including equilibrium core conditions; or (2) There has been acceptable testing of a prototype plant over a sufficient range of normal operating conditions, transient conditions, and specified accident sequences, including equilibrium core conditions. If a prototype plant is used to comply with the testing requirements, then the NRC may impose additional requirements on siting, safety features, or operational conditions for the prototype plant to protect the public and the plant staff from the possible consequences of accidents during the testing period.
The NRC staff will review the design documents for the ECCS valves described in the following portions of NuScale DCA Part 2, Tier 2:
Section 3.9.6, Functional Design, Qualification, and Inservice Testing Programs for Pumps, Valves, and Dynamic Restraints, Section 6.3, Emergency Core Cooling System, and Chapter 19, Probabilistic Risk Assessment and Severe Accident Evaluation.
The NRC staff will conduct this audit in accordance with the guidance provided in the Office of New Reactors (NRO) Office Instruction NRO-REG-108, Regulatory Audits (Reference 5).
IV.
REGULATORY AUDIT SCOPE The primary scope of this audit is the NRC staff review of the planning, performance, and results of the ECCS valve design demonstration testing to evaluate compliance with 10 CFR
5 52.47 and 50.43(e). In addition, the audit scope includes the NRC staff review of NuScales completion of follow-up items from the ECCS valve FMEA audit.
V.
DOCUMENTS/INFORMATION NECESSARY FOR THE AUDIT NuScale will make available the documentation for the planning, performance, and results of the ECCS valve design demonstration testing in the NuScale eRR. The documents related to the ECCS valve design demonstration testing include, for example, test plans, procurement requirements, set-up and performance specifications, procedures, acceptance criteria, QA provisions and implementation, equipment and instrumentation descriptions, calibration information, and results and evaluation. In addition, NuScale will make available documentation prepared as part of the follow-up items to the ECCS valve FMEA audit. Some information might need to be provided at the ECCS valve vendor test facility. Appropriate handling and protection of proprietary information and export control information (ECI) shall be acknowledged and observed throughout the audit.
VI.
SPECIAL REQUESTS The NRC staff requests that NuScale provide the technical staff with access to the audit documents. NuScale can upload the requested documents into the NuScale eRR for the NRC staffs review. In addition, NuScale should make the applicable design documents available at its Rockville office or the ECCS valve vendor facility as requested. During the audit, the NRC staff will have questions and discussion items for the NuScale subject matter experts. When the NRC staffs review of the documents associated with a specific issue is complete, the NRC staff will notify NuScale that these documents may be removed from the eRR; thereby minimizing their residence time in the eRR.
VII.
AUDIT ACTIVITIES AND DELIVERABLES The NRC staff will review the documents identified in Section V of this audit plan.
The audit will be conducted from March 20 through July 25, 2019, from 7:00 AM to 3:00 PM, at the NuScale Rockville Office; the NRC Rockville Office; or the ECCS valve vendor facility in Farmingdale, New York.
The NRC Project manager (PM) will coordinate with NuScale in advance of audit activities to identify specific documents to be made available and any changes to the audit schedule. The NRC staff proposes to audit the ECCS valve design demonstration testing at the valve vendor facility during the week of June 2, 2019 (based on the test schedule provided by NuScale).
The audit entrance/exit meetings and audit meetings are planned as follows:
Entrance Meeting: March 20, 2019.
Exit Meeting: July 25, 2019.
Bi-weekly Audit Telephone Conference (as needed): Monday 11:00 AM - 12:00 PM EST.
Daily debriefs during the onsite audit at the valve vendor facility over the week of June 2, 2019.
6 The NRC staff acknowledges that proprietary and ECI documents are requested to be made available. These documents will be handled appropriately throughout the audit. While the NRC staff will take notes, the NRC staff will not remove hard copies or electronic files from the audit site. The NRC staff will treat notes as potentially containing proprietary or ECI material with appropriate controls.
During the bi-weekly telephone conferences, the NRC staff will discuss with NuScale any issues identified during the audit, and their resolution either through audit activities or by another mechanism, such as RAIs or public meetings. The NRC staff will also identify any new emerging information needs as well as documents that may be removed from the eRR.
At the completion of the audit, an audit summary will be provided by the technical reviewers to the PM for prompt issuance to the applicant as well as a public version of the same. The NRC staff will issue an audit summary within 90 days that will be declared and entered as an official agency record in ADAMS.
The audit outcome may be used to identify any additional information to be submitted on the docket for making regulatory decisions, and will assist the NRC staff in the issuance of RAIs (if necessary) to support the NRC review of the NuScale DCA in preparation of the NRCs Safety Evaluation Report.
If necessary, any circumstances related to the performance of the audit will be communicated to Marieliz Vera, NRC, at 301-415-5861, or Marieliz.VeraAmadiz@nrc.gov.
VIII.
REFERENCES
- 1. NuScale Standard Plant Design Certification Application, Revision 2.
- 2. NRC Letter, NuScale Power, LLC - Acceptance of an Application for Standard Design Certification of a Small Modular Reactor, ADAMS Accession No. ML17074A087, March 23, 2017.
- 3. NRC Report of Initial Regulatory Audit for Emergency Core Cooling System Valves in NuScale Power, LLC, Design Certification Application, ADAMS Accession No. ML18052A079, February 26, 2018.
- 4. NRC Report of Regulatory Audit of Failure Modes and Effects Analysis and Other Supporting Documents of Emergency Core Cooling System Valves in the NuScale Power, LLC, Design Certification Application, ADAMS Accession No. ML18219B634, August 14, 2018.
- 5. NRO-REG-108, Regulatory Audits, ADAMS Accession No. ML081910260, April 2, 2009.