ML18199A273
| ML18199A273 | |
| Person / Time | |
|---|---|
| Site: | 05200045 |
| Issue date: | 07/25/2018 |
| From: | Adrian Muniz NRC/NRO/DLSE |
| To: | Jennivine Rankin NRC/NRO/DLSE |
| Muniz A | |
| References | |
| Download: ML18199A273 (8) | |
Text
July 25, 2018 MEMORANDUM TO: Jennivine Rankin, Acting Branch Chief Licensing Branch 3 Division of Licensing, Siting, and Environmental Analysis Office of New Reactors FROM: Adrian Muniz, Project Manager /RA/
Licensing Branch 3 Division of Licensing, Siting, and Environmental Analysis Office of New Reactors
SUBJECT:
AUDIT PLAN FOR THE ADVANCED BOILING-WATER REACTOR DESIGN PEAK CLADDING TEMPERATURE INCREASE GE Hitachi Nuclear Energy (GEH) reported emergency core cooling system evaluation model changes or errors that resulted in increased peak cladding temperature (PCT) for the advanced boiling-water reactor (ABWR) standard plant design that was certified by rule in Title 10 of the Code of Regulations Part 52, License, Certifications, and Approvals for Nuclear Power Plants, Appendix A as part of their application to renew the ABWR design certification.
The U.S Nuclear Regulatory Commission staff will audit the documentation that supports the PCT impact reported by GEH. A copy of the audit plan is enclosed.
Docket No.: 52-045
Enclosure:
As stated CONTACT: Adrian Muniz, NRO/DLSE 301-415-4093
ML18199A273 *via e-mail NRC-001 OFFICE PM:DLSE LA:DLSE BC:DSRA/SRSB BC:DLSE PM:DLSE NAME AMuniz SGreen RKaras JRankin AMuniz DATE 7/19/18 07/17/18 7/17/18* 7/19/18 7/25/18 U. S. NUCLEAR REGULATORY COMMISSION AUDIT PLAN FOR THE REGULATORY AUDIT OF GE HITACHI NUCLEAR ENERGY ADVANCED BOILING-WATER REACTOR DESIGN CERTIFICATION RENEWAL APPLICATION -
TITLE 10 TO THE CODE OF FEDERAL REULATIONS 50.46, ACCEPTANCE CRITERIA FOR EMERGENCY CORE COOLING SYSTEMS FOR LIGHT-WATER NUCLEAR POWER REACTORS PEAK CLADDING TEMPERATURE REPORTS APPLICANT: GE Hitachi Nuclear Energy (GEH)
APPLICANT CONTACT: Walter Schumitsch, GEH Senior Project Manager DURATION: Phase 1: GEH Electronic Reading Room (eRR), August 6, through August 10, 2018 Phase 2: August 13, through August 17, 2018 Phase 3: August 20, through August 31, 2018 LOCATION: Phase 1: U.S. Nuclear Regulatory Commission (NRC)
Headquarters via GEH eRR Phase 2: General Electric-Hitachi Nuclear Energy (GEH),
3901 Castle Hayne Road Wilmington, NC 28401 Phase 3: U.S. NRC Headquarters via GEH eRR AUDIT TEAM: James Gilmer, NRO Reactor Systems Branch Rebecca Karas, NRO Reactor Systems Branch Chief Reed Anzalone, NRR, Nuclear Performance and Code Review Branch Hanry Wagage, NRO, (support, if needed),
Containment and Ventilation Branch Adrian Muniz, NRO, Project Manager I. BACKGROUND AND OBJECTIVES By letter dated December 7, 2010, GEH submitted for approval an application to renew the U.S.
Advanced Boiling-Water Reactor (ABWR) design certification rule pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 52, License, Certifications, and Approvals for Nuclear Power Plants. The U.S. Nuclear Regulatory Commission (NRC) staff is performing a detailed review of this application to enable the staff to reach a conclusion on whether to grant the renewal application.
Enclosure
By letters dated October 12, 2016 and October 10, 2017, GEH reported emergency core cooling system (ECCS) evaluation model (EM) changes or errors that resulted in increased peak cladding temperature (PCT) in support of their application to renew the ABWR design certification in 10 CFR Part 52, Appendix A. These annual reports were made pursuant to the reporting requirement of the ECCS rule, 10 CFR 50.46, Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors.
As a result of public teleconference discussions between GEH and NRC staff, supplemental information was submitted for the 2016 annual report, in Letter MFN 16-059, Supplement 1, dated October 12, 2016. Estimates of the change in PCT were provided for each EM change or error. These estimates were based on evaluations performed for operating conventional boiling-water reactor (BWR) plants, as well as design evaluations performed for a non-domestic ABWR. Also provided were proposed markups to the ABWR Design Control Document (DCD).
Additional supplemental information was provided by GEH in Letter M170071, dated March 20, 2017. This letter provides an explanation of the bases used to develop the PCT change estimates and also addresses an NRC staff concern that the effect of the changes on other design aspects should be evaluated. Further proposed DCD markups were also provided.
To facilitate the NRC staffs understanding and evaluation of information supporting the ABWR design certification renewal application, an audit will be conducted at the GEH facility and by means of the GEH eRR from NRC Headquarters. The focus of this audit will be on documentation and other information used to form the bases for the estimates of the PCT changes and expected impacts on other design analyses and evaluations.
An audit entrance meeting will be conducted via teleconference on August 6, 2018. At the beginning of Audit Phase 1, the discussion will focus on both NRC and GEH expectations for the audit and any general information the audit team should be made aware of, such as eRR usage, types of documentation available, and planned review milestones. An audit exit meeting will be conducted at the conclusion of Audit Phase 3.
The objectives of this audit are for the NRC staff to:
- gain a better understanding of the detailed calculations, analyses, and bases underlying the estimates of PCT changes resulting from licensing basis EM changes and error corrections, as well as the basis and supporting documentation for GEHs stated approach to incorporate updated codes and methods to the design basis for the ABWR, including specifics regarding the noted error related to Prime implementation;
- better understand the differences between domestic ABWR design parameters and those for the conventional BWRs and international ABWR used in generating the estimates (e.g., fuel type, thermal power);
- better understand the impact, if any, to other loss-of-coolant accident (LOCA) acceptance criteria (e.g., maximum cladding oxidation, hydrogen generation);
- better understand if the methodology continues to meet NRC regulations and conforms to regulatory guidance for 10 CFR 50.46, Appendix K;
- better understand the bases behind statements in GEHs Letter M170071, dated March 20, 2017, related to the continued applicability of ABWR containment analyses, radiological analyses and various Chapter 15 analyses in the DCD;
- confirm other models were used for analyses related to combustible gas, station blackout, reactor pressure vessel (RPV) fluence and decay heat, as stated in GEHs Letter M170071, dated March 20, 2017;
- develop requests for additional information for issues not fully resolved by audit or that require a formal, docketed response.
II. REGULATORY AUDIT BASIS In 10 CFR 50.46, sets forth the requirements for the design and evaluation of light water reactor ECCS, including the need to calculate the ECCS cooling performance using an acceptable EM for a number of postulated LOCAs of different sizes, locations, and other properties sufficient to provide assurance that the most severe LOCAs have been evaluated.
Pursuant to 10 CFR 50.46(a)(3), each holder of or applicant for a standard design certification approval under Part 52 is required to estimate the effect of any change to or error in an acceptable EM or in the application of such a model1 to determine if the change or error is significant. For this purpose, a significant change or error is one which results in a calculated peak fuel cladding temperature different by more than 50° F from the temperature calculated for the limiting transient using the last acceptable model, or is a cumulation of changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50° F. For each change to or error discovered in an acceptable EM or in the application of such a model that affects the temperature calculation, the applicant or holder of a construction permit, operating license, combined license, or manufacturing license shall report the nature of the change or error and its estimated effect on the limiting ECCS analysis to the Commission at least annually.
In 10 CFR Section 52.47(a)(4) states, in part, that a DC application must contain an FSAR that includes:
An analysis and evaluation of the design and performance of structures, systems, and components with the objective of assessing the risk to public health and safety resulting from operation of the facility and including determination of the margins of safety during normal operations and transient conditions anticipated during the life of the facility, and the adequacy of structures, systems, and components provided for the prevention of accidents and the mitigation of the consequences of accidents.
In 10 CFR Section 52.57(a) states that a DC renewal application must:
Not less than 12 nor more than 36 months before the expiration of the initial 15-year period, or any later renewal period, any person may apply for renewal of the certification. An application for renewal must contain all information necessary to bring 1
For the sake of brevity, this document will refer to changes to or errors in an acceptable evaluation model or in the application of such a model, as changes or errors in an evaluation model.
up to date the information and data contained in the previous application. The Commission will require, before renewal of certification, that information normally contained in certain procurement specifications and construction and installation specifications be completed and available for audit if this information is necessary for the Commission to make its safety determination. Notice and comment procedures must be used for a rulemaking proceeding on the application for renewal. The Commission, in its discretion, may require the use of additional procedures in individual renewal proceedings.
An audit is needed to confirm the basis for the PCT change estimates and qualitative assessments of other design impacts made by GEH in the various annual reports and which ultimately are reflected in revisions to the ABWR renewal application, consistent with the requirement of 10 CFR 52.57(a) to bring the information up to date.
III. REGULATORY AUDIT SCOPE The scope of this audit includes information, documents, and supporting calculations related to the development of PCT change estimates and assessments of other design impacts. In addition to the initial set of audit documents and other information provided by GEH to the NRC Audit Team for review, the NRC reviewers may request other information as needed to achieve audit objectives. These documents will be listed as references in the audit report prepared by the staff following the conclusion of the audit.
As a result of insights gained through this audit, the staff may identify the need to expand the team supporting this audit or issue separate audit plans associated with other technical areas.
IV. SPECIAL REQUESTS To the extent possible, the NRC staff requests that the supporting documentation which GEH utilized to address each of the specific items listed in Appendix A of this Audit Plan be made available to the NRC Audit Team in GEHs eRR at the beginning of Audit Phase 1 and remain accessible for the duration of the audit. Use of the eRR will allow multiple reviewers in different geographic locations to examine the same document at the same time, which is expected to improve the efficiency and reduce the cost of the audit.
Additional documents needed may be identified as the review progresses. When the staffs review of the documents associated with a specific issue is complete, the Audit Team lead or Project Manager will notify the GEH Project Manager that these documents can be removed from the ERR.
For Audit Phase 2 at the GEH facility, the NRC staff requests access to a general meeting room which can accommodate the entire NRC Audit Team and the GEH personnel supporting the audit. A separate closed meeting space with a conference telephone is needed for Audit Team caucusing and discussions with NRC Headquarters.
In addition, the NRC Audit Team may request in-person discussions with GEH personnel to facilitate the staffs understanding of the audit material. Such meetings will be scheduled based on mutual availability.
V. AUDIT ACTIVITIES AND DELIVERABLES The NRC Audit Team will conduct this audit in accordance with the guidance provided in NRO-REG-108, Regulatory Audits (Reference 2). The NRC staff acknowledges the proprietary nature of the information requested, and will handle it appropriately throughout the audit.
While the Audit Team will take notes during the course of the audit, no hard copies or electronic files will be removed from the audit site(s).
The audit will commence on August 6, 2018. The audit is scheduled to conclude August 31, 2018, and will consist of three stages. During the course of the Phase 1 and Phase 2 reviews, the Audit Team may identify the need for discussions with GEH subject matter experts in design areas not directly associated with PCT determination, such as containment and hydrodynamic design, Chapter 15 non-LOCA analyses, etc. For Audit Phase 3, additional NRC subject matter experts may be added to the audit team to review documentation related to their specialty areas. Access to the GEH eRR may be needed for these added team members.
During the eRR Phase 1 and Phase 3, teleconference phone discussions between GEH and NRC may be necessary to communicate and resolve issues. The NRC Project Manager will notify the GEH Project Manager and schedule the discussions at mutually agreed upon times.
This audit plan may be revised as necessary to include additional phases to address specific identified items, or a new audit plan may be issued. An Audit Report will be generated within 90 days following completion of Phase 3.
If necessary, any concerns related to the conduct of the audit shall be communicated to the NRC Project Manager.
VI. REFERENCES
- 1. GEH Letter No. M170071, March 20, 2017, Peak Cladding Temperature/10 CFR 50.46 for the GE Hitachi Nuclear Energy Advanced Boiling Water Reactor (ABWR)
Design Certification Renewal Application, Supplemental Information.
- 2. NRO-REG-108, Regulatory Audits, April 2, 2009, Agencywide Documents Access and Management System Accession No. ML081910260.
- 3. GEH Letter No. MFN-16-059, Peak Cladding Temperature for GE Hitachi Nuclear Energy Advanced Boiling Water Reactor Design Certification Rule Renewal Application, August 19, 2016.
- 4. GEH Letter No. MFN-16-059, Supplement 1 Peak Cladding Temperature 2016 Annual Reporting Under 10 CFR 50.46 for the GE Hitachi Nuclear Energy Advanced Boiling Water Reactor (ABWR) Design Certification and the ABWR Design Certification Renewal Application, October 12, 2016.
Appendix A - Requested Documents
- 1. Calculational package(s), calcnotes, letters, internal GEH correspondence, and any other documentation which support the development of ABWR LOCA PCT error estimates, including the assessment of LOCA EM changes and known errors, as reported to the NRC in the ABWR annual PCT reports.
- 2. Calculational package(s), calcnotes, letters, internal GEH correspondence, and any other documentation which support the development of ABWR LOCA maximum cladding oxidation and hydrogen generation, including the assessment of LOCA EM changes and known errors, as reported to the NRC in GEH Letter No. M170071 (Reference 1).
- 3. Calculational package(s), calcnotes, letters, internal GEH correspondence, and any other documentation which support the development of the GEH ABWR LOCA EM used to meet the requirements of 10 CFR 50.46, including the assessment of LOCA EM changes, known errors, and transition to modern fuel, as reported to the NRC in GEH Letter No. M170071 (Reference 1).
- 4. Calculational package(s), calcnotes, letters, internal GEH correspondence, and any other documentation which support the assessment of continued acceptability of ABWR containment analyses, radiological analyses and various Chapter 15 analyses in the DCD, as reported to the NRC in GEH Letter No. M170071 (Reference 1).