Text

Biennial Problem Identification and Resolution Inspection Report 05000261/2024010
	ML24116A152
Person / Time
Site:	Robinson
Issue date:	04/30/2024
From:	Renee Taylor; NRC/RGN-II/DRP/RPB3
To:	Basta L; Duke Energy Progress
References
	IR 2024010
	Download: ML24116A152 (16)
	v • d • e

SUBJECT:

H.B. ROBINSON STEAM ELECTRIC PLANT - BIENNIAL PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000261/2024010

Dear Laura Basta:

On March 21, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed a problem identification and resolution inspection at your H.B. Robinson Steam Electric Plant and discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.

The NRC inspection team reviewed the stations problem identification and resolution program to confirm that the station was complying with NRC regulations and licensee standards. Based on the samples reviewed, the team determined that your program complies with NRC regulations and applicable industry standards such that the Reactor Oversight Process can continue to be implemented.

The team also evaluated the stations effectiveness in identifying, prioritizing, evaluating, and correcting problems, reviewed licensee audits and self-assessments, and its use of industry and NRC operating experience information. The results of these evaluations are in the enclosure.

Finally, the team reviewed the stations programs to establish and maintain a safety-conscious work environment and interviewed station personnel to evaluate the effectiveness of these programs. Based on the teams observations and the results of these interviews, the team found no evidence of challenges to your organizations safety-conscious work environment. Your employees appeared willing to raise nuclear safety concerns through at least one of the several means available.

No findings or violations of more than minor significance were identified during this inspection.

April 30, 2024 This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely, Ryan C. Taylor, Chief Reactor Projects Branch 3 Division of Reactor Projects Docket No. 05000261 License No. DPR-23

Enclosure:

As stated

Inspection Report

Docket Number:

05000261

License Number:

DPR-23

Report Number:

05000261/2024010

Enterprise Identifier:

I-2024-010-0034

Licensee:

Duke Energy Progress, LLC

Facility:

H.B. Robinson Steam Electric Plant

Location:

Hartsville, SC

Inspection Dates:

March 04, 2024 to March 21, 2024

Inspectors:

B. Bishop, Senior Project Engineer

V. Gaffney, Resident Inspector

T. Griffin, Project Engineer

R. Reyes, Project Engineer

A. Ruh, Reactor Inspector

Approved By:

Ryan C. Taylor, Chief

Reactor Projects Branch 3

Division of Reactor Projects

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a biennial problem identification and resolution inspection at H.B.

Robinson Steam Electric Plant, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.

List of Findings and Violations

No findings or violations of more than minor significance were identified.

Additional Tracking Items

Type Issue Number Title Report Section Status URI 05000261/2024010-01 Service Water Design Basis for Isolation of Passive Failures 71152B Open

INSPECTION SCOPES

Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.

OTHER ACTIVITIES - BASELINE

71152B - Problem Identification and Resolution Biennial Team Inspection (IP Section 03.04)

Main article: IP 71152

(1) The inspectors performed a biennial assessment of the effectiveness of the licensees Problem Identification and Resolution program, use of operating experience, self-assessments and audits, and safety conscious work environment.

Problem Identification and Resolution Effectiveness: The inspectors assessed the effectiveness of the licensees Problem Identification and Resolution program in identifying, prioritizing, evaluating, and correcting problems. The inspectors also conducted a five-year review of aging issues associated with piping corrosion and service water system performance. The corrective actions for the following non-cited violations and findings were evaluated as part of the assessment: NCV 2022011-01, 2022011-02, 2022004-01, 2023003-01, 2023003-02, 2023004-01, 2023402-01, 2023402-02, FIN 2023001-01.

Operating Experience: The inspectors assessed the effectiveness of the licensees processes for use of operating experience. The licensee's use of NRC Information Notices 2021-01 "Risk Insights from High Energy Arcing Fault Operating Experience and Analyses," 2022-02 "Lessons Learned from U.S. Nuclear Regulatory Commission Inspections of Design-Basis Capability of Power-Operated Valves at Nuclear Power Plants", 2023-01 "Operating Experience Related to the Unexpected Loss of Operating Security Power Due to Inadequate Testing and Maintenance" and Regulatory Issue Summary 2022-02 "Operational Leakage" were reviewed. Other significant external operating experience regarding emergency preparedness, reactor coolant systems and emergency diesel generators were also reviewed to determine whether the licensee appropriately used operating experience information.

Self-Assessments and Audits: The inspectors assessed the effectiveness of the licensees identification and correction of problems identified through audits and self-assessments. Specifically, departmental assessments for mechanical maintenance, instrumentation & electrical maintenance, radiation protection, employee concerns, license renewal and the corrective action program audits were reviewed to determine whether the licensee appropriately assessed performance and identified areas for improvement.

Safety Conscious Work Environment: The inspectors assessed the effectiveness of the stations programs to establish and maintain a safety-conscious work environment. Inspectors reviewed the employee concerns program and conducted employee interviews with licensee staff from various departments and levels of the organization to assess whether issues exist that may represent challenges to the free flow of information, and to determine whether underlying factors exist that would produce a reluctance to raise nuclear safety concerns.

INSPECTION RESULTS

Assessment 71152B Corrective Action Program Effectiveness Problem Identification: The inspectors reviewed a sampling of identified issues across various plant systems such as the reactor coolant, control room heating, ventilation and cooling, residual heat removal, emergency diesel generator, dedicated shutdown diesel generator, auxiliary feedwater, service water, component cooling water, chemical and volume control, and safety injection systems. The inspectors determined that the licensee was effective in promptly identifying deficient conditions and entering them into the corrective action program (which includes the work management system), and there was a low threshold for entering issues into the corrective action program. These conclusions were based on a review of the requirements for initiating condition reports and/or work requests, as described in licensee procedure AD-PI-ALL-0100, "Corrective Action Program." For the samples selected, the licensee's application of trending was largely effective to identify low level trends with equipment and human performance prior to the issues becoming more significant problems.

However, inspectors did identify a minor performance deficiency associated with AD-EG-ALL-1210, "Maintenance Rule Program," in regard to a lack of trending unavailability hours within the site's Maintenance Rule program for the dedicated shutdown diesel generator. Also, inspectors made observations about a Fire Protection Health Report that considered an incipient fire detection system to have excellent health despite having exceeded the site's established performance limit on unavailability hours during the health report's review period.

Also, in regard to trending, since the last biennial problem identification and resolution inspection, there were two NRC-identified trends described in inspection reports 05000261/2022004 and 05000261/2023002 that had not been previously identified by the licensee. Overall, the team determined that the licensee's corrective action program complied with regulatory requirements and self-imposed or other industry standards necessary for continued participation in the Reactor Oversight Process.

Problem Prioritization and Evaluation: Based on the review of condition reports, work orders, and work requests, the inspectors concluded that problems were mostly prioritized and evaluated in accordance with licensee guidance. One instance of a minor violation was identified during the inspection, by licensee personnel, that a corrective action due date was improperly extended without the required justification or supervisory approval required by AD-PI-ALL-0100. Inspectors also made an observation concerning the prioritization of monitoring activities required by AD-EG-ALL-1503, "Fire Protection Performance Monitoring and Other Program Elements" because the licensee planned to allow 226 days to develop a corrective action plan for an incipient fire detection system had exceeded the site's established performance limit on unavailability hours. The inspectors determined that adequate consideration was generally given to system or component operability and associated plant risk. However, during review of service water aging issues, inspectors had concerns with the evaluations of several failures of the south header check valve SW-545. Operability evaluations for these issues suggested that the valve's failure to fully seat did not affect system operability as long as the valve maintained its pressure boundary (no external leakage). However, these evaluations appeared to not consider the impacts of passive failures described in the updated final safety analysis report (UFSAR). As a result, there appeared to be a misunderstanding of the service water system's design basis for passive failures and an unresolved item was opened to determine whether a performance deficiency existed in this area. Finally, the inspectors determined that plant personnel had conducted cause evaluations in compliance with the licensee's corrective action program procedures and cause determinations were appropriate, and considered the significance of the issues being evaluated.

Corrective Actions: Based on a review of corrective action documents, interviews with licensee staff, and verification of completed corrective actions, the inspectors determined that corrective actions were timely, commensurate with the safety significance of the issues, and effective, in that conditions adverse to quality were corrected. The team determined that the licensee was effective in developing corrective actions that were appropriately focused.

Assessment 71152B Use of Operating Experience The team determined that the station's processes for the use of industry and NRC operating experience information were effective and complied with regulatory requirements and licensee standards. The implementation of these programs adequately supported nuclear safety. The team concluded that operating experience was adequately evaluated for applicability and that appropriate actions were implemented in accordance with applicable procedures.

Assessment 71152B Self-Assessments and Audits The inspectors determined that the licensee was effective at performing self-assessments and audits to identify issues at a low level, properly evaluated those issues, and resolved them commensurate with their safety significance. The self-assessments and audits were adequately self-critical and performance-related issues were being appropriately identified.

The inspectors verified that action requests were created to document areas for improvement and findings and verified that actions had been completed consistent with those recommendations.

Assessment 71152B Safety Conscious Work Environment The licensee actively monitored for a safety conscious work environment through self-assessments using their proceduralized nuclear safety culture and employee concerns programs AD-NO-ALL-0204, AD-NO-ALL-0202 respectively. Employees interviewed appeared willing to raise nuclear safety concerns through at least one of the several means available. Based on interviews with plant staff and reviews of the latest safety culture survey results, the team found no evidence of challenges to a safety-conscious work environment.

Unresolved Item (Open)

Service Water Design Basis for Isolation of Passive Failures URI 05000261/2024010-01 71152B

Description:

An unresolved item was identified. During review of repeated failures of south header check valve SW-545, inspectors identified a potential licensee misunderstanding of the facility's design basis regarding passive failure design and mitigation in the service water system. Engineers appeared to consider that a failed open check valve would still support system train operability since the system would maintain its pressure boundary and be capable of supplying flow to vital equipment. However, section 9.2.1.2 of the UFSAR described that the system design assured flow to at least one component cooling heat exchanger and two containment air recirculation units with a single failure of any pipe or valve body in the service water system. In the case of a failed pipe upstream of SW-545, proper seating of the check valve could be an important safety function for ensuring sufficient flow to these vital components.

Inspectors also noted that the UFSAR stated the two service water supply headers were redundant, independent, and that all supply header isolation valves were motor operated and controlled remotely from the control room. However, inspectors found that the system was normally aligned with two, normally open, manual, chain-operated valves (SW-18, SW-19)connecting the redundant, independent headers in the auxiliary building and that AOP-022 called for local operator action of these valves for header isolation purposes during a loss of service water condition. After reviewing historical licensing correspondence and the licensee's available design basis documentation, it appeared that the facility's use of manual isolation valves did not match the description in the current UFSAR, or original FSAR. Early nuclear supplier correspondence, and the licensee's early version of a system description, prior to receiving an operating license in 1970, indicated that these manual valves should be normally closed and that only the remotely controlled header isolation valves located at the service water intake structure were needed to ensure the system's ability to mitigate a passive failure on one of the headers. Despite these original descriptions, the facility began initial operation using SW-18 and SW-19 as normally open, manual valves without modifying or applying the FSAR's design basis of providing the control room with remote motor operated control of these isolation valves.

Later, via NRC Temporary Instruction 2515/118, a 1993 Service Water System Operational Performance Inspection (SWSOPI) was conducted at the station and the team issued a report (ML14182A250) which made statements about the adequacy of the system's design features for mitigating piping ruptures. Specifically, that "The system was always operated with the two trains interconnected at the supply header of the service water pumps and at the suction and discharge of the service water booster pumps. Adequate design features were installed for mitigation of piping rupture at these locations." These statements did not reference whether the design basis had been adequately translated into the system procedures and drawings that were reviewed by the inspectors and warrants further evaluation before determining whether a performance deficiency exists.

Planned Closure Actions: Inspectors will need to determine whether SW-18 and SW-19 are supply header isolation valves per the UFSAR description and then evaluate whether that determination is a contrary staff position to that described in the SWSOPI inspection report.

Licensee Actions: The licensee reviewed the system design and concluded that the facility was appropriately analyzed for the current configuration, was in compliance with the station's design basis documents, and no action was required.

Corrective Action References: NCR 2510239 Minor Performance Deficiency 71152B Unrecorded Maintenance Rule Unavailability Minor Performance Deficiency: Procedure AD-EG-ALL-1210, "Maintenance Rule Program,"

section 5.5 required monthly recording of certain system unavailability hours by the responsible engineer as part of monitoring system performance. Inspectors identified that all unavailability hours for the dedicated shutdown diesel generator (DSDG) had not been entered into the station's software. Specifically, a planned maintenance outage in August 2023 was not recorded. NCR 2508078 documented this issue.

Screening: The inspectors determined the performance deficiency was minor. This issue was of minor significance because when the unavailability period was considered, it was still demonstrated that performance of the DSDG was being effectively controlled through appropriate preventive maintenance such that the DSDG remained capable of performing its intended function (i.e., the requirements of 10 CFR 50.65(a)(1)/(a)(2) were always met).

Minor Violation 71152B Improper Corrective Action Extension Minor Violation: During the course of the inspection, the licensee identified a corrective action (CORR) assignment 2402792-22, to track implementation of a preventive maintenance addition, was extended without justification or supervisor approval as required by AD-PI-ALL-0100, "Corrective Action Program" section 5.11.3. NCR 2507956 was written to document this issue.

Screening: The inspectors determined the performance deficiency was minor. The issue was of minor significance because the corrective action was completed, and no safety equipment impacts, or safety consequences resulted from the improper extension.

Enforcement:

This failure to comply with 10 CFR 50 Appendix B, Criterion 5 "Instructions, Procedures, and Drawings" constitutes a minor violation that is not subject to enforcement action in accordance with the NRCs Enforcement Policy.

Observation: Delayed Action Plan Development 71152B In October 2023, NCR 2489931 identified that the control rod drive cabinet incipient fire detection system (21-IFD) exceeded the site's established performance limit on unavailability hours. AD-EG-ALL-1503, "Fire Protection Performance Monitoring and Other Program Elements," Section 5.5.3.b expected that a Monitoring Expert Panel would approve a corrective action plan before the next health reporting cycle ending on December 31, 2023.

This action was extended to May 23, 2024 (226 days from initial identification), which was not commensurate with the typical 30-day timelines expected for other similar evaluations described in AD-PI-ALL-0100, "Corrective Action Program," Attachment 4. Additionally, the Fire Protection Health Report for December 2023 gave the system a Green/Excellent assessment because a sufficient number of unavailability hours had rolled off by the time the health report was completed, but it did not annotate that the equipment had surpassed the unavailability thresholds during the reporting period or that a recovery plan to prevent future unavailability hours was not in place. The health report did have a mechanism to track the open action, but this mechanism would allow the action to extend beyond 1 year before negatively impacting the fire protection health report. Overall, since the station's procedures were not prescriptive, no specific procedural deficiencies were identified. However, because the station's implementation of fire protection performance monitoring and health reporting in this case did not yield results commensurate with other similar evaluations detailed in AD-PI-ALL-0100, it was questionable whether the expectation from AD-EG-ALL-1503 was being met that "monitoring activities should be analyzed in a timely manner to ensure that appropriate action is taken."

EXIT MEETINGS AND DEBRIEFS

The inspectors verified no proprietary information was retained or documented in this report.

On March 21, 2024, the inspectors presented the biennial problem identification and resolution inspection results to Laura Basta and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

71152B

Calculations

RNP-M/MECH-

28

Reduced SW Flow to EDG

71152B

Calculations

RNP-M/MECH-

1802

Safety Related Pump Minimum Performance Requirements

71152B

Corrective Action

Documents

2453208, 2454469,

2457237, 2459555,

2467993, 2480973,

2500961, 2502170,

2432550, 2452496,

2457008, 2457009,

2483800, 2446440,

2501943, 2453411,

2441064, 2445048,

2446289, 2499482,

2473607, 2473800,

2473926, 2480170,

28806, 2504918,

2471571, 2471351,

2489931, 2437413,

2433409, 2423011,

2433052, 2437867,

2481522, 2332207,

2498502, 2448208,

2495306, 2454340,

2455086, 2475694,

2476348, 2477070,

2480117, 2452540,

2430828, 2432250,

2432924, 2438722,

2448003, 2450429,

2450631, 2451850,

2452519, 2454020,

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

2456997, 2474317,

2478603, 2481645,

2485021, 2487237,

2473362, 2465345,

2468543, 2478000,

2498543, 2231248,

2465552, 2467004,

2476039, 2486098,

2486648, 2434829,

2441885, 2443098,

2444426, 2453599,

2457516, 2507524,

2503017, 2440612,

2441153, 2443071,

2444070, 2396736,

2399406, 2402792,

2433017, 2435056,

2441065, 2453457,

2443909, 2454666,

2487283, 2434388,

2460492, 2490238,

2489286, 2402785,

2433015, 2433019,

2453581, 2451316,

2459060, 2479212,

2491032, 2481751,

2464035, 2460197,

2458574, 2458218,

2437108, 2433519,

2492271, 2490179,

2483624, 2473826,

2473791, 2472636,

2468490, 2463639,

2484039, 2369694,

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

28690, 2462522,

2484265, 2488245,

2371506, 2479210,

2406292, 2479211,

2479229, 2489928,

2488778, 2483160,

2450671, 2448360,

2471242, 2477025,

2475771, 2477068,

2456574, 2458910,

2403507, 2404364,

2403201, 2403327,

2403905, 2406297,

2401764, 2405065,

2403841, 2404066,

2402903, 2403254,

2499130, 2488995,

2479875, 2478602,

2473693, 2473268,

2441087

71152B

Corrective Action

Documents

Resulting from

Inspection

2507956

CORR extension without justification or supervisor approval

71152B

Corrective Action

Documents

Resulting from

Inspection

2508078

Failure to trend maintenance rule unavailability for

Dedicated Shutdown Diesel system.

71152B

Drawings

G-190199 Sheet 1