ML23345A079
| ML23345A079 | |
| Person / Time | |
|---|---|
| Site: | 05200050 |
| Issue date: | 12/16/2023 |
| From: | Beverly Smith NRC/NRR/DNRL |
| To: | Renee Taylor Office of Nuclear Reactor Regulation |
| References | |
| Download: ML23345A079 (6) | |
Text
December 16, 2023 MEMORANDUM TO: Robert M. Taylor Deputy Office Director New Reactors Office of Nuclear Reactor Regulation FROM: Brian W. Smith, Director /RA/
Division of New and Renewed Licenses Office of Nuclear Reactor Regulation
SUBJECT:
NUSCALE STANDARD DESIGN APPROVAL APPLICATION REVIEW INTERIM LESSONS LEARNED REPORT The purpose of this memorandum is to document lessons learned and planned improvements performed by the Division of New and Renewed Licenses (DNRL) stemming from the ongoing NuScale Standard Approval Application Phase A review. The enclosed interim lessons learned report includes recommendations and specific actions to improve the review process.
The following are the reports major observations:
- The extended audit process has worked well. Many of the issues the staff have raised in the audit would have been communicated as request for additional information (RAI) in previous reviews. As audits progress, and the staff is not getting the information needed to make their safety finding, they should move to issue an RAI.
- The staff should be developing their safety evaluation report input throughout the audit review to ensure that they are capturing all the information that may be missing from the application that is needed to make their safety finding. This will allow these information needs to be a part of the audit and, if the staff is at an impasse with the applicant on the information needed to make a safety finding, issue an RAI. An RAI developed in this manner is, in effect, an open item in the staffs review.
- RAIs should have clear and appropriate background and a description of the issue, specific regulatory basis that is directly related to the question being asked, and specific information needs that will support the staff evaluating the issue and making their safety finding. This should include any specific information that needs to be included in a revised final safety analysis report.
CONTACT: Mahmoud Jardaneh, NRR/DNRL 301-415-4126
R. Taylor 2 The DNRL staff is in the process of implementing the five recommendations outlined in the report. Please contact Mahmoud Jardaneh, Chief of the New Reactor Licensing Branch, if you have any specific questions regarding implementation of the recommendations.
Docket No. 05200050
Enclosure:
Lessons Learned Report
ML23345A079 *via email NRR-043 OFFICE NRR/DNRL/NRLB:PM NRR/DNRL/NRLB: BC* NRR/DNRL/NLIB:LA NRR/DNRL:D NAME GTesfaye MJardaneh SGreen BSmith DATE 12/11/2023 12/12/2023 12/13/2023 12/16/2023 NUSCALE STANDARD DESIGN APPROVAL APPLICATION REVIEW INTERIM LESSONS LEARNED REPORT M. Mitchell, J. Colaccino, G. Tesfaye November 2023 The purpose of this document is to identify interim lesson learned observations that, if implemented, would improve the review of the NuScale Standard Design Approval Application (SDAA). The observations focus on the audit process, identification of requests for additional information (RAI) and the development of an advanced safety evaluation report (ASER) with no open items. Improvements that are being suggested include a better-defined transition process between the completion of the audit for each chapter or licensing topical report (LTR) to any needed RAIs as well as clear expectations on the development of ASERs to support the identification of RAIs that are needed to make a finding in the safety evaluation report (SER).
The lessons learned report on the review of the NuScale design certification (DC) application (Agencywide Documents Access and Management Systems Accession No. ML22088A161) highlighted improvements that should be implemented for the use of audits and issuance of RAIs. The report stated that the NRC should use consistent approaches, such as focused durations; clear and tangible objectives; routine schedules for progress reports; and phased approaches that prevent moving on to subsequent portions of audits before both the applicant and the NRC agree that precursor activities have been satisfactorily completed. The report also discussed improvements to the RAI process incorporated into Revision 1 of LIC-115 to enhance the RAI process through greater focus on the regulatory requirements, safety significance, and clarity of RAIs. The report further stated that additional opportunities are available to focus the staffs review only on RAIs necessary to support the reasonable assurance finding. Finally, regarding safety evaluations, the report stated that a more concerted effort to streamline SERs at the beginning of the review would further concentrate efforts on the most safety-significant aspects of the design and create a sufficient safety basis for the staffs regulatory conclusions.
The project team charter for the NuScale US460 SDAA implemented these improvements. Of note, the charter specified that in Phase A of the review the NRC would perform audits and develop (1) items that could result as RAIs, and (2) an ASER without open items. Across all the individual chapter and LTR reviews, hundreds of issues have been identified and resolved through this process. The Project Managers, Technical Staff, and applicant have frequently cooperated well and resolved these issues without having to engage higher levels of management. These activities have been implemented consistent with both the lessons learned report and the review. Of the approximately 700 issues that have been entered in the audit spread sheet to date for the 19 review chapters and four LTRs, approximately 65% have been resolved during the audit and the remaining are under the NRC review, awaiting NuScale response, or converted to a formal RAI. The majority of issues identified in the audit and resolved would have been RAIs in previous similar reviews. Their resolution represents a success in implementing the audit process for this review.
Enclosure
Transitioning issues out of the audit process and into a more formalized RAI is addressed in the audit plan. However, in practice, it is clear that more direction needs to be provided to the staff regarding when to convert an issue into an RAI.
The following are a number of observations that support this assertion:
- There is an impression among some members of the staff that managements message when starting this review was that RAIs were to be avoided and that having to resort to RAIs would be viewed as a failure. While that was almost certainly not intended that seems to be what the staff, in many cases, heard.
- Although the audits were executed under the general principle of giving the applicant at least two opportunities to resolve an issue under the audit before elevating it to an RAI, specific review areas for high effort chapters where the staff has reached an impasse in the audit after one round of draft response would benefit from the issuance of an RAI that identifies the information needed for the staff to make its safety finding.
- There also likely needs to be a bit of additional rigor when establishing by when the audit process for a particular chapter/LTR/etc. must close and any remaining unresolved issues be converted to formal RAIs. In some cases, the Project Managers, Technical Staff, and NuScale extended the audit phases for a particular Chapter/LTR/etc. and were successful in using the additional time to efficiently and effectively close the outstanding issues. However, in other cases, always with very good intentions, the extension of the audit phase out to a point close to when the SE input was due for a particular Chapter/LTR/etc. did not always leave an obvious window of opportunity to close the audit, issue an RAI, get a response, and complete the SE while staying on schedule.
- In some cases, technical branches expressed a reluctance to start documenting RAIs on a time frame which would have supported them being issued more promptly after the closure of the associated audit because they did not want to be seen as charging a few additional hours to the NuScale review to prepare just in case RAI questions if their last ditch attempts to resolve issues at the audit deadline failed. While their rigor with regard to managing hours charged may be appreciated, this may have been to the detriment of being able to keep the reviews moving by getting what turned out to be necessary RAIs issued more promptly.
The review charter specifies that the activities in Phase A include the staff performing an audit and developing (1) items that could result as RAIs, and (2) an ASER without open items. While this change eliminated preparation of a safety evaluation with open items, the extensive use of audits has enabled the staff to identify issues that previously would have been transmitted to the applicant as RAIs. The issues that are converted to RAIs out of the audit are, in effect, the remaining open items in the chapter.
As weve modified the review process, we may have lost some of the granularity of the former process with the DC review which had an earlier SE with open items phase which basically forced reviewers to get to that point in their writing. There is some sense at least that for certain Chapter/LTR reviews, reviewers may not have clearly identified all their issues as early as they could have because they didnt write up their draft SE input early.
This observation is clouded somewhat by the specifics of the NuScale low/medium effort SDAA chapter reviews where reviewers were directed to use the SE that was already written for the corresponding DC chapter and only make minor modifications to address what changed (if anything) between the DC and SDAA.
Recommendations:
- 1. Management should convey that the use of audits is not intended to eliminate RAIs.
Rather, the purpose of the audit is to identify all the review issues and, when they cannot be resolved in the audit, are converted into RAIs that focus on obtaining information that the staff needs to make a safety finding.
- 2. Allow audit issues to be framed and sent as RAIs as soon as it has become clear that resolution via the audit is unlikely.
- 3. The audit for a particular Chapter or LTR should close 2.5 to 3 months prior to the due date for the associated SE with all outstanding issues written up and converted to RAIs within one week of the closure of the audit. Discretion should be allowed to extend the audit if the staff and PMs agree that the issue can be closed relatively quickly, even if it is discovered late in the audit.
- 4. The staff should strive to develop their draft safety evaluation input for various chapter/LTR reviews significantly ahead of the schedule for the associated chapter ASER in order to better ensure that all potential issues are identified early.
- 5. In order to further the efficient and effective issuance of RAIs needed to make a safety finding, NRLB PMs should review the management comments to draft RAIs during the prior round of RAIs to become aware of certain types or pattern of improvement needs and apply them during the PM review of draft RAIs. NRLB PMs should identify whether certain deficiencies (e.g., lack of technical/guidance clarity, improperly cited regulations, etc.) indicate that more guidance/direction should be provided to reviewers to improve the initial quality of RAIs.