ML23310A180
| ML23310A180 | |
| Person / Time | |
|---|---|
| Site: | 99902056 |
| Issue date: | 11/06/2023 |
| From: | NRC |
| To: | NRC/NRR/DNRL |
| References | |
| Download: ML23310A180 (8) | |
Text
From:
Allen Fetter Sent:
Monday, November 6, 2023 2:45 PM To:
Schiele, Raymond Joseph; Montague, Kelvin Jevon; kecasey@tva.gov Cc:
Greg Cranston; Sean Gallagher; ClinchRiver-CPSafDocsPEm Resource
Subject:
Readiness Assessment Initial Observations on draft PSAR Chapter 14 and Section 17.4 (Phase 1) - draft Clinch River CP application Attachments:
Initial Observations, PSAR 14_Readiness Assessment_Phase 1.pdf; Initial Observations PSAR 17.4_Readiness Assessment_Phase 1.pdf Good Afternoon, Attached are initial NRC staff observations on draft PSAR Chapter 14 and Section 17.4 (Phase 1) that staff viewed in TVAs electronic reading room as part of Phase 1 of the Readiness Assessment of the draft Clinch River CP application.
If TVA makes any future updates to the draft PSAR chapters and sections for follow up readiness assessment observations by NRC staff, please contact me, Greg Cranston or Sean Gallagher.
- Thanks, Allen H. Fetter, Senior Project Manager U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of New and Renewed Licenses New Reactor Licensing and Infrastructure Branch Washington, D.C.
301-415-8556 (Office) 301-385-5342 (Mobile)
Hearing Identifier:
ClinchRiver_CPSafDocs_Public Email Number:
3 Mail Envelope Properties (MW4PR09MB939664064F0AF88FDDDEA3C685AAA)
Subject:
Readiness Assessment Initial Observations on draft PSAR Chapter 14 and Section 17.4 (Phase 1) - draft Clinch River CP application Sent Date:
11/6/2023 2:44:38 PM Received Date:
11/6/2023 2:44:42 PM From:
Allen Fetter Created By:
Allen.Fetter@nrc.gov Recipients:
"Greg Cranston" <Gregory.Cranston@nrc.gov>
Tracking Status: None "Sean Gallagher" <Sean.Gallagher@nrc.gov>
Tracking Status: None "ClinchRiver-CPSafDocsPEm Resource" <ClinchRiver-CPSafDocsPEm.Resource@nrc.gov>
Tracking Status: None "Schiele, Raymond Joseph" <rjschiele@tva.gov>
Tracking Status: None "Montague, Kelvin Jevon" <kjmontague@tva.gov>
Tracking Status: None "kecasey@tva.gov" <kecasey@tva.gov>
Tracking Status: None Post Office:
MW4PR09MB9396.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 769 11/6/2023 2:44:42 PM Initial Observations, PSAR 14_Readiness Assessment_Phase 1.pdf 127273 Initial Observations PSAR 17.4_Readiness Assessment_Phase 1.pdf 88039 Options Priority:
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No Reply Requested:
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Readiness Assessment - Phase 1 Initial Readiness Assessment Observationsi on draft PSAR Chapter 14, Initial Test Program, Clinch River CP application November 6, 2023 14.1 Preliminary Safety Analysis Report Content 14.1.1 Scope of Test Program Staff Observations:
- 1. The PSAR should specify the scope of the Initial Test Program (ITP) to include safety-related systems and components, and any systems or components not classified as safety-related but within the scope of special treatment requirements of 10 CFR Part 50.
- 2. The PSAR should specify that the nuclear power plant will be designed and constructed to accommodate the necessary preoperational and startup testing. The preoperational and startup testing required should be a consideration early in the design process. It is not an expectation that detailed, step-by-step written procedures are readily available at the CP stage. However, the PSAR should provide a high-level description of the types of testing to be conducted to ensure that significant testing is not overlooked in the design and construction process.
14.1.2 Plant Design Features That Are Special, Unique, or First of a Kind Staff Observations:
- 1. The PSAR should discuss the plans to ensure that the preoperational and/or startup testing for the Isolation Condenser System (ICS) and ICS Condensate Return to the Chimney will be correlated to the 10 CFR 50.43(e) testing and the system/component qualification testing.
- 2. The PSAR should discuss preoperational testing plans for Reactor Pressure Vessel Isolation Valves in BWRX-300.
- 3. The PSAR should provide a detailed description of the BWRX-300 design specifying design features that are first of a kind (FOAK) and need to meet 10 CFR 50.43(e).
- 4. The PSAR should describe the plans to consider the potential for large thermal gradients during startup testing that can exceed Section III stress limits or cause excessive fatigue usage due to the low flow, low decay heat conditions.
14.1.3 Conformance of Test Programs with Regulatory Guides Staff Observations:
- 1. The PSAR only refers to portions of Regulatory Guide (RG) 1.68 for ITP activities. The PSAR should discuss the use of RG 1.68 and its related RGs. For example, the PSAR should contain a list of standard preoperational and startup testing discussed in RG 1.68 such as reactor internals flow-induced vibration testing piping system vibration and thermal expansion testing.
Readiness Assessment - Phase 1 14.1.4 Utilization of Plant Operating and Testing Experiences at Other Reactor Facilities Staff Observations:
- 1. As noted in RG 1.70, the PSAR should describe the schedule for conducting a study of available information on reactor plant operating experiences and implementing the program.
The PSAR should describe the plans to address the safety issues described in NRC generic communications, such as power-operated valve capability.
14.1.5 Test Program Schedule Staff Observations:
- 1. The NRC staff will need to review the test procedures as part of the Operating License (OL) application review and might need more than 60 days (as indicated in the PSAR) to review the procedures and provide feedback.
14.1.6 Trial Use of Plant Operating and Emergency Procedures Staff Observations: No comments.
14.1.7 Augmenting Staff During the Test Program Staff Observations: No comments i Input provided by NRR/DEX/EMIB staff.
Readiness Assessment - Phase 1 Initial Readiness Assessment Observationsi on draft PSAR Section 17.4, Reliability Assurance Program During Design Phase Clinch River CP application November 6, 2023 Basis for Observation/Comment Readiness Assessment Observations SECY-93-087 and SECY-94-084 Responsibilities within the D-RAP organization are not clear. In Section 17.4.2, GEH BWRX-300 is described as being responsible for the D-RAP, but no specific job titles and responsibilities are identified. The information provided in the PSAR should be of sufficient detail that it can be verified.
SECY-93-087 and SECY-94-084 In Section 17.4.1, the program is described as preliminary, and it is stated that the program will be updated as the design continues. Is this intended to refer to the D-RAP process itself the list of SSCs that result from implementation of the process? This paragraph also discusses the focus on the performance of functions versus systems; is this part of the process subject to change?
The PSAR should clearly identify information that is preliminary, information that is not provided for the construction permit application, and information that sufficiently complete to support the findings and conclusions to be made by the NRC staff.
SECY-93-087 and SECY-94-084 Flowcharts or other graphics depicting the D-RAP process have been helpful for conveying the inputs and outputs of the D-RAP process for other applicants.
SECY-93-087 and SECY-94-084 In Section 17.4.3.1 on risk significance criteria, the methodology to determine the criteria is not sufficiently described and it is stated that the FV and RAW values may be revised as the PSA evolves. Other applicants have submitted risk significance topical reports to propose a methodology for determining risk significance and there may be advantages to addressing the risk significance determination criteria separately, but in parallel with the construction permit application.
Readiness Assessment - Phase 1 Basis for Observation/Comment Readiness Assessment Observations SECY-93-087 and SECY-94-084 In Section 17.4.3.2, the pre-application material includes the statement, "To address gaps in the PSA, deterministic analysis can be used...." There are other reasons to use deterministic analysis to support the determination of risk significance, such as not to over-rely on risk-based information, and to address inherent limitations of the PSA, especially for an unbuilt design. The deterministic inputs should also be described in additional detail, and the D-RAP process should specify the roles and responsibilities for considering different deterministic inputs.
SECY-93-087 and SECY-94-084 The composition of the expert panel should be described such that the staff can verify the expertise and experience of the expert panel members.
SECY-93-087 and SECY-94-084 In Section 17.4.5, the PSA should not be the only input to the list of risk-significant SSCs.
Globally, the description of the D-RAP process should reflect its planned implementation and the PSA should not be over relied on for risk significance determination. It should be clear, for all individual elements that make up the D-RAP, what inputs are considered and how they are used (e.g., risk-based vs. risk-informed).
SECY-93-087 and SECY-94-084 Section 17.4.2 describes the GEH Organization responsible for D-RAP. Section 17.4.6 describes the RAP will be implemented by TVA during operations. The application should be clear on the responsibilities between these two organizations, especially related to the transition between construction and operational RAP activities.
Readiness Assessment - Phase 1 Basis for Observation/Comment Readiness Assessment Observations SECY-93-087 and SECY-94-084, SRP 17.4 The last paragraph before section 17.4.1 states, "the programmatic elements for developing and implementing the D-RAP (organization, design control, procedures, SSCs identification, and implementation) that will be applied prior the initial fuel load are described." Some of these elements (e.g.,
design control, procedures) are briefly mentioned under organization, but it is not apparent how these are controlled to support the D-RAP process. There is no description of the corrective action program, records, or audit plans as discussed in SRP 17.4.
Overarching The context for the D-RAP/RAP is minimal related to any interfaces with the safety strategy, safety and risk categorization provided in Section 3.2, and to a lesser extent PRA and risk insights determined from Section 15.6. The submittal and review will benefit from an understanding of the complete picture.
SECY-93-087 and SECY-94-084 The purposes of the reliability assurance program do not include minimize the frequency of transients that challenge risk significant SSCs. Does the D-RAP not intend to follow the purposes as outlined in the SECY papers? The applicant should address any alternative to D-RAP that will address purposes that are not covered by D-RAP.
Overarching For a construction permit application, it is understood that the final list of D-RAP SSCs may not be necessary for the preliminary safety analysis report (PSAR). Staff requests that TVA/GEH describe the plans for D-RAP/RAP such that the staff understands the timeline of the review for CP and OL, including any planned topical reports on this topic. It will be helpful to understand when various documentation will be available (e.g., a preliminary list of D-RAP SSCs for audit) so that staff can appropriately delineate the scope of the review for the construction permit application.
Readiness Assessment - Phase 1 Basis for Observation/Comment Readiness Assessment Observations SECY-93-087 and SECY-94-084 It is not clear how the D-RAP will be utilized during the design and equipment specification phases if there is no list of D-RAP SSCs.
Further, there is no discussion of whether the D-RAP will be utilized during the construction phase. The applicant should consider including a discussion of the maintenance/QC of the D-RAP list prior to completion of the detailed PSA.
SECY-93-087 and SECY-94-084 Section 17.4.3 states, "A list of SSCs that are associated with the initiation, prevention, detection, or mitigation of any failure sequence and have a significant impact in reducing the possibility of damage to fuel and/or associated release of radionuclides is developed and controlled as a BWRX-300 D-RAP report, following development of the detailed PSA."
The PSAR should clarify whether these are these the functions referenced in Section 17.4.1 or how this list of functions relates to the functions that will be identified by the D-RAP expert panel.
SECY 93-087 and SECY 94-084 Does TVA plan to identify regulatory treatment of non-safety systems (RTNSS) SSCS? If so, are these SSCs determined to be risk significant?
SECY 93-087 and SECY 94-084 The PSAR should include a description of how expert panel decisions are documented.
i Input provided by from NRR/DRA/APLC