IR 05000387/2024010

Biennial Problem Identification and Resolution Inspection Report 05000387/2024010 and 05000388/2024010

ML24318A683
Person / Time
Site:	Susquehanna
Issue date:	11/13/2024
From:	Sarah Elkhiamy Division of Operating Reactors
To:	Berryman B Susquehanna
References
IR 2024010
Download: ML24318A683 (1)

Text

November 13, 2024

SUBJECT:

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - BIENNIAL PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000387/2024010 AND 05000388/2024010

Dear Brad Berryman:

On October 3, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed a problem identification and resolution inspection at your Susquehanna Steam Electric Station, Units 1 and 2 and discussed the results of this inspection with Mark Jones, Senior Manager, Engineering, 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.

Additionally, two findings of very low safety significance (Green) are documented in this report.

One of these findings involved a violation of NRC requirements. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy. If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:

Document Control Desk, Washington, DC 20555 0001; with copies to the Regional Administrator, Region I; the Director, Office of Enforcement; and the NRC Resident Inspector at Susquehanna Steam Electric Station, Units 1 and 2.

If you disagree with a cross-cutting aspect assignment or a finding not associated with a regulatory requirement in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555 0001; with copies to the Regional Administrator, Region I; and the NRC Resident Inspector at Susquehanna Steam Electric Station, Units 1 and 2.

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 (CFR) 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely, Sarah H. Elkhiamy, Chief Projects Branch 4 Division of Operating Reactor Safety

Docket Nos. 05000387 and 05000388 License Nos. NPF-14 and NPF-22

Enclosure:

As stated

Inspection Report

Docket Numbers:

05000387 and 05000388

License Numbers:

NPF-14 and NPF-22

Report Numbers:

05000387/2024010 and 05000388/2024010

Licensee:

Susquehanna Nuclear, LLC

Facility:

Susquehanna Steam Electric Station, Units 1 and 2

Location:

Berwick, PA

Inspection Dates:

September 16, 2024 to October 3, 2024

Inspectors:

R. Clagg, Senior Project Engineer

J. England, Senior Resident Inspector

C. Khan, Senior Project Engineer

S. Obadina, Reactor Operations Engineer

Approved By:

Sarah H. Elkhiamy, Chief

Projects Branch 4

Division of Operating Reactor Safety

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a biennial problem identification and resolution inspection at Susquehanna Steam Electric Station, Units 1 and 2, 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

Failure to Complete a Modification on the A Low-Pressure Turbine Results in Manual Reactor Trip Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green FIN 05000387/2024010-01 Open/Closed None (NPP)71153 A self-revealed, Green finding was identified when the licensee failed to complete a modification on the A low-pressure turbine resulting in a loss of main condenser vacuum and subsequent manual reactor trip. Specifically, in March 2002, the licensee failed to cut and cap the portion of a turbine bearing wastewater and oil drain piping internal to the Unit 1 main condenser within the required distance from a pipe coupling and associated pipe support. The remaining approximately 40-inch length of unsupported piping was subjected to steam erosion and steam induced vibration. On November 10, 2023, a weld on this piping failed resulting in rapidly degrading main condenser vacuum which necessitated a rapid downpower and subsequent manual reactor trip.

Failure to Repair Excessive Leakage on the Inboard B Main Steam Isolation Valve Results in Exceeding Technical Specification Limits Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green NCV 05000387/2024010-02 Open/Closed

[H.14] -

Conservative Bias 71153 The inspectors identified a Green finding and associated non-cited violation (NCV) of Susquehanna Steam Electric Station, Unit 1, Technical Specification (TS) 5.4.1a, when the licensee failed to initiate a work mechanism to repair excessive leakage of HV141F022B, inboard B main steam isolation valve (MSIV). Specifically, the licensee failed to reduce the leakage to <10,000 standard cubic centimeters per minute (sccm) to maintain margin of the MSIV as required by NDAP-QA-0412, Leakage Rate Testing Program, Revision 24, which resulted in reduced margin to inoperability of the MSIV. Due to the reduced margin, the MSIV became inoperable during the operating cycle and resulted in the licensees failure to take the required actions of TS Limiting Condition for Operation (LCO) 3.6.1.3 within the required completion times.

Additional Tracking Items

Type Issue Number Title Report Section Status LER 05000387/2023-004-00 LER 2023-004-00 for Susquehanna Steam Electric Station, Unit 1, Manual Reactor Scram Due to Degraded Main Condenser Vacuum 71153 Closed LER 05000387/2023-004-01 LER 2023-004-01 for Susquehanna Steam Electric Station, Unit 1, Manual Reactor Scram Due to Degraded Main Condenser Vacuum 71153 Closed LER 05000387/2024-001-00 LER 2024-001-00 for Susquehanna Steam Electric Station, Unit 1, Main Steam Isolation Valve Leakage 71153 Closed LER 05000387/2024-001-01 LER 2024-001-01 for Susquehanna Steam Electric Station, Unit 1, Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear 71153 Closed

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)

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 review of the emergency diesel generators and a 5-year review of the safety-related 4 kilovolt (kV) electrical system. The corrective actions for the following NCVs and licensee event reports (LERs) were evaluated as part of the assessment:

NCV 2024002-01, NCV 2023004-01, NCV 2023004-02, NCV 2023001-01, NCV 2022404-01, NCV 2022003-01, NCV 2022003-02, NCV 2022013-01, NCV 2022010-01, NCV 2022010-02, NCV 2022010-03, NCV 2022010-04, LER 05000387/2022-001-00 and 01, LER 05000387/2022-002-00 and 01, LER 05000387, 388/2023-001-00, LER 05000387/2023-002-00, LER 05000387/

2023-004-00 and 01, LER 05000387/2024-001-00 and 01, LER 05000388/2022-001-00, LER 05000387, 388/2022-003-00, and LER 05000388/2023-001-00.

• Operating Experience: The inspectors assessed the effectiveness of the licensees processes for use of operating experience.

• Self-Assessments and Audits: The inspectors assessed the effectiveness of the licensees identification and correction of problems identified through audits and self-assessments.

• Safety-Conscious Work Environment: The inspectors assessed the effectiveness of the licensees programs to establish and maintain a safety-conscious work environment.

71153 - Follow-up of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)

The inspectors evaluated the following licensees event reporting determinations to ensure it complied with reporting requirements:

(1) LER 05000387/2023-004-00, Manual Reactor Scram Due to Degraded Main Condenser Vacuum (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24009A217), and revision LER 05000387/2023-004-01, Manual Reactor Scram Due to Degraded Main Condenser Vacuum (ML24239A847). The circumstances surrounding these LERs are documented in the Inspection Results Section of this report, FIN 05000387/2024010-01. These LERs are closed.

(2) LER 05000387/2024-001-00, Main Steam Isolation Valve Leakage (ML24144A278),and revision LER 05000387/2024-001-01, Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear (ML24234A326). The circumstances surrounding these LERs are documented in the Inspection Results Section of this report, NCV 05000387/2024010-02. These LERs are closed.

INSPECTION RESULTS

Assessment 71152B Problem Identification and Resolution Program Effectiveness

The inspectors determined that the licensees problem identification and resolution program was in most cases effective and adequately supported nuclear safety and security.

Identification: The inspectors reviewed a sample of issues that have been processed through the licensees problem identification and resolution program since the last biennial team inspection, including NCVs of regulatory requirements and other documented findings. The inspectors determined that, usually, the licensee identified issues and entered them into the corrective action program at a low threshold and timely manner. The inspectors did identify a minor performance deficiency as documented in the Inspection Results Section of this report.

Prioritization and Evaluation: Based on the samples reviewed, the inspectors determined that the licensee was generally effective at prioritizing and evaluating issues commensurate with the safety significance of the identified problem. The inspectors observed that at licensee corrective action program meetings, issues were screened and prioritized at the appropriate level and that corrective actions were assigned to address the issues.

Corrective Action: The inspectors determined that the licensee was effective in developing corrective actions that were appropriately focused to correct the identified problems.

Assessment 71152B Operating Experience

The inspectors reviewed operating experience captured in the corrective action program and sampled operating experience from NRC, industry, vendors, and third-party groups. Overall, for the samples selected, the inspectors determined that the licensee was performing basic assessments for station applicability.

Assessment 71152B Self-Assessment and Audits

The inspectors determined that the licensee was adequately performing self-assessments and audits in accordance with licensee procedures and implementing corrective actions as needed.

Assessment 71152B Safety-Conscious Work Environment

The inspectors interviewed a total of 27 individuals in one-on-one interviews. The purpose of these interviews was

(1) to evaluate the willingness of the licensee to raise nuclear safety issues,

(2) to evaluate the perceived effectiveness of the corrective action program at resolving identified problems, and

(3) to evaluate the licensees safety-conscious work environment. The personnel interviewed were randomly selected by the inspectors from Engineering, Maintenance, Operations, Radiation Protection, Chemistry, Emergency Preparedness, and Security. To supplement these discussions, the inspectors interviewed the Employee Concerns Program (ECP) coordinator to assess their perception of the site employees' willingness to raise nuclear safety concerns and reviewed the ECP case log and select case files. All individuals interviewed indicated that they would raise safety concerns.

All individuals felt that their management was receptive to receiving safety concerns and generally addressed them promptly, commensurate with the significance of the concern. Most interviewees indicated that they were adequately trained and proficient on initiating condition reports (CRs). Most interviewees were aware of the licensee's ECP, and all stated they would use the program if necessary and expressed confidence that their confidentiality would be maintained if they brought issues to the ECP. The inspectors determined that the processes in place to mitigate potential safety culture issues were adequately implemented.

Minor Performance Deficiency 71152B Improper Storage of 4 kV Breakers, 13.8 kV Breakers, and Ground and Test Devices

Minor Performance Deficiency: The inspectors determined that the licensees failure to follow procedures NDAP-QA-0503, General Housekeeping, Revision 52, and NDAP-QA-0440, Control of Transient Combustible/Hazardous Materials, Revision 29, when storing 4 kV breakers, 13.8 kV breakers, and ground and test devices that were not in use was a performance deficiency. Specifically, it has been station practice for more than 10 years to keep this equipment in areas that did not meet the requirements of these procedures.

Section 5.1.1.c of NDAP-QA-0503 states that when not in use, then all material, equipment, and tools used during work activities must be properly stored. Section 5.1.2.c states that all transient equipment must be returned to designated storage areas when not in use. The equipment listed was not properly stored in designated storage areas when not in use.

NDAP-QA-0440, Section 5.1.9.a, states that all transient combustible storage (e.g., cables) in a restricted area shall require a permit except Class A combustible materials stored in a closed metal/concrete container. Section 5.1.9.b.7 states storage of all cords (e.g., cables)longer than 25 feet require a permit, and Section 5.1.9.b.8 states that all cords (e.g., cables)in a restricted zone require a permit. The breakers and ground and test devices contained cables greater than 25 feet, and some of the equipment was stored in restricted areas. The cables were not in fully closed metal containers, and a permit was not obtained for any of this equipment as required by NDAP-QA-0440.

Screening: The inspectors reviewed IMC 0612, Appendix B, Issue Screening, issued on August 9, 2023, and determined that the issue was minor because it is associated with the Protection Against External Factors attribute of the Mitigating Systems cornerstone and did not adversely affect the cornerstone objectives because the licensee was able to demonstrate that the transient combustibles were well below the fire hazards analysis limits and the equipment would not have negatively impacted nearby equipment during a design basis seismic event.

Failure to Complete a Modification on the A Low-Pressure Turbine Results in Manual Reactor Trip Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green FIN 05000387/2024010-01 Open/Closed None (NPP)71153 A self-revealed, Green finding was identified when the licensee failed to complete a modification on the A low-pressure turbine resulting in a loss of main condenser vacuum and subsequent manual reactor trip. Specifically, in March 2002, the licensee failed to cut and cap the portion of a turbine bearing wastewater and oil drain piping internal to the Unit 1 main condenser within the required distance from a pipe coupling and associated pipe support.

The remaining approximately 40-inch length of unsupported piping was subjected to steam erosion and steam induced vibration. On November 10, 2023, a weld on this piping failed resulting in rapidly degrading main condenser vacuum which necessitated a rapid downpower and subsequent manual reactor trip.

Description:

On November 10, 2023, Unit 1 experienced a loss of main condenser vacuum which required a rapid downpower and subsequent manual reactor trip. Initial investigation by the licensee identified that a weld on the Unit 1 A low-pressure turbine #3 bearing waste water and oil drain (slop drain) piping, internal to the main condenser, had failed resulting in the degradation of main condenser vacuum. The licensee entered the issue into their corrective action program as CR-2023-17617 and subsequently completed a root cause analysis.

The inspectors reviewed CR-2023-17617 and the associated root cause analysis. The inspectors noted that in March 2002, the licensee completed a plant modification documented in Engineering Change (EC) 391977 on the Unit 1 main condenser to cut and cap slop drain line piping. This was done to address a potential vulnerability of the piping to fail due to erosion and corrosion which could result in air in-leakage to the main condenser and a loss of condenser vacuum. The inspectors reviewed EC 391977, implementing plant control work order (PCWO) 392091, and the associated drawings. The inspectors noted that PCWO 392091 contained work instructions to cut and cap drain line piping inside the main condenser. The inspectors reviewed the associated drawings and noted that the drain line piping was required to be cut and capped along a 6-inch section of piping adjacent to an existing pipe coupling and associated pipe support. This location would have allowed the existing pipe support to remain in place. The inspectors noted that CR-2023-17617 documented the drain line piping was cut and capped approximately 24 inches above the required location which resulted in approximately 40 inches of piping to remain in the main condenser without a pipe support. The remaining piping was subjected to steam erosion and steam induced vibration which resulted in failure of a drain piping weld on November 10, 2023, and the subsequent loss of main condenser vacuum.

The licensee also submitted LER 05000387/2023-004-00, Manual Reactor Scram Due to Degraded Main Condenser Vacuum (ML24009A217), and revision LER 05000387/

2023-004-01, Manual Reactor Scram Due to Degraded Main Condenser Vacuum (ML24239A847).

The inspectors concluded that the licensee failed to complete the plant modification as required by PCWO 392091.

Corrective Actions: Corrective actions included installation of a gasketed plate and plug on the failed drain line penetration. In addition, the licensee conducted extent of condition reviews to identify other Unit 1 drain lines that were susceptible to failure. These lines were then remediated or tested based on if they were internal or external to the main condenser.

Similar extent of condition reviews and appropriate corrective actions are planned for Unit 2 during the next scheduled refueling outage.

Corrective Action References: CR-2023-17617

Performance Assessment:

Performance Deficiency: The inspectors determined that the licensees failure to complete a modification for the Unit 1 A low-pressure turbine #3 bearing wastewater and oil drain (slop drain) piping as required by PCWO 392091 work instructions was a performance deficiency.

Specifically, in March 2002, the licensee failed to cut and cap the portion of the slop drain line piping internal to the Unit 1 main condenser within the required distance from a pipe coupling and associated pipe support. The remaining approximately 40-inch length of unsupported piping was subjected to steam erosion and steam induced vibration. On November 10, 2023, a weld on this piping failed resulting in rapidly degrading main condenser vacuum which necessitated a rapid downpower and subsequent manual reactor trip.

Screening: The inspectors reviewed IMC 0612, Appendix B, Issue Screening, issued on August 9, 2023, and determined that the issue was more than minor because it is associated with the Human Performance attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Specifically, the failure to complete the wastewater and oil drain piping modification caused a loss of main condenser vacuum which resulted in a rapid downpower and subsequent manual reactor trip.

Significance: The inspectors assessed the significance of the finding using Exhibit 3 of IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, issued on November 30, 2020, and determined it to be of very low safety significance, Green, because it did not result in a loss of mitigation equipment relied upon to transition the plant from the onset of the trip to a stable condition because the main condenser remained available for decay heat removal.

Cross-Cutting Aspect: Not Present Performance: No cross-cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance.

The disposition of this finding closes LER 05000387/2023-004-00, Manual Reactor Scram Due to Degraded Main Condenser Vacuum, and LER 05000387/2023-004-01, Manual Reactor Scram Due to Degraded Main Condenser Vacuum.

Enforcement:

The inspectors did not identify a violation of regulatory requirements associated with this finding.

Failure to Repair Excessive Leakage on the Inboard B Main Steam Isolation Valve Results in Exceeding Technical Specification Limits Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green NCV 05000387/2024010-02 Open/Closed

[H.14] -

Conservative Bias 71153 The inspectors identified a Green finding and associated NCV of Susquehanna Steam Electric Station, Unit 1, TS 5.4.1a when the licensee failed to initiate a work mechanism to repair excessive leakage of HV141F022B, inboard B MSIV. Specifically, the licensee failed to reduce the leakage to <10,000 sccm to maintain margin of the MSIV as required by NDAP-QA-0412, Leakage Rate Testing Program, Revision 24, which resulted in reduced margin to inoperability of the MSIV. Due to the reduced margin, the MSIV became inoperable during the operating cycle and resulted in the licensees failure to take the required actions of TS LCO 3.6.1.3 within the required completion times.

Description:

On March 28, 2024, during local leak rate testing (LLRT) conducted during the Susquehanna, Unit 1, refueling outage, the licensee identified that the as-found leakage through the inboard B MSIV was 57,166 sccm which exceeded the TS surveillance requirements limit of 100 standard cubic feet per hour (scfh) or 47,194 sccm for individual valve leakage. The licensee entered the issue into their corrective action program as CR-2024-04850 and subsequently completed an apparent cause evaluation.

The licensee also submitted LER 05000387/2024-001-00, Main Steam Isolation Valve Leakage (ML24144A278), and revision LER 05000387/2024-001-01, Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear (ML24234A326).

The inspectors reviewed CR-2024-04850 and the associated apparent cause evaluation and noted that the direct cause for inoperability of the MSIV was the result of normal wear on the valve body seat over the previous operating cycle compounded by inherent low margin following valve repair in 2022. The inspectors also noted that the condition existed, during the operating cycle, for a longer period than allowed by TS LCO 3.6.1.3. The licensees causal evaluation documented a significant amount of internal operating experience associated with MSIV leakage.

The inspectors noted operating experience, beginning in 2007, which documented multiple, and at times repeat, failures of MSIVs. These failures resulted in the licensee establishing a post repair administrative limit of 10,000 sccm in the LLRT administrative procedures NDAP-QA-0412, Leakage Rated Testing Program, and MT-083-011, Main Steam Isolation Valve Disassembly, Inspection, and Reassembly. The inspectors noted that three of the six times the MSIV as-left leakage exceeded the post repair administrative limit of 10,000 sccm, the MSIV exceeded the TS value when as-found tested during the next refueling outage.

The inspectors reviewed MT-083-011, completed during the 2022 Unit 1 refueling outage, and noted that step 6.1.4, which states confirm post maintenance LLRT for repaired MSIV is less than 10,000 sccm per NDAP-QA-0412, Leakage Rate Test Program, Attachment A, LLRT Administrative Limits note (5), was marked complete. The inspectors reviewed CR-2022-06760 which documented the as-left leakage of the B inboard MSIV as 39,750 sccm. The inspectors noted that CR-2022-06760

(1) did not document the post repair administrative limit,

(2) stated that the leakage may be artificially high due to less-than-optimal high friction conditions (cold/dry steel) for stroking the valve, and

(3) stated that the leakage did not exceed the TS limit and recommended monitoring.

The inspectors reviewed NDAP-QA-0412 and noted that step 5.1.2f(5) states, [i]n order to maintain margin, an administrative maintenance limit has been established for each MSIV of 80 percent of the technical specification limit (see Att. A). If this limit is exceeded, a work mechanism shall be initiated to repair the barrier exhibiting the excessive leakage and reduce the leakage to <10,000 sccm. Attachment A, note (5), lists the administrative maintenance limit as 37,755 sccm. The inspectors determined that the as-left leakage of the MSIV during the 2022 Unit 1 refueling outage exceeded the administrative limit in NDAP-QA-0412.

The inspectors concluded that the licensee failed to initiate a work mechanism to repair excessive leakage of HV141F022B, Inboard B MSIV, as required by NDAP-QA-0412, Leakage Rate Testing Program, Revision 24, which resulted in MSIV inoperability during the operating cycle and the licensees failure to take the required actions of TS LCO 3.6.1.3 within the required completion times.

Corrective Actions: Corrective actions included performing an internal seat repair for the MSIV and revising the LLRT implementing procedures (SE-1(2)59-021 through 024, LLRT of Main Steam Line Isolation Valves Penetration Number) to include the 10,000 sccm post repair administrative limits and recommended actions to take if the limits are exceeded as well as classifying the administrative limits at the alert level.

Corrective Action References: CR-2024-04850

Performance Assessment:

Performance Deficiency: The inspectors determined that the licensees failure to initiate a work mechanism to repair excessive leakage of HV141F022B, inboard B MSIV, and reduce the leakage to <10,000 sccm was a performance deficiency. Specifically, the licensee failed to maintain margin of the MSIV as required by NDAP-QA-0412, Leakage Rate Testing Program, Revision 24, which resulted in reduced margin to inoperability of the MSIV. Due to the reduced margin, the MSIV became inoperable during the operating cycle and resulted in the licensees failure to take the required actions of TS LCO 3.6.1.3 within the required completion times.

Screening: The inspectors reviewed IMC 0612, Appendix B, Issue Screening, issued on August 9, 2023, and determined that the issue is more than minor because it is associated with the Human Performance attribute of the Barrier Integrity cornerstone and adversely affected the cornerstone objective to provide reasonable assurance that physical design barriers (fuel cladding, reactor coolant system, and containment) protect the public from radionuclide releases caused by accidents or events. Specifically, the licensee failed to repair the excessive leakage of the B inboard MSIV, which resulted in inoperability of the MSIV during the operating cycle.

Significance: The inspectors assessed the significance of the finding using Exhibit 3 of IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, issued on November 30, 2020, and determined it to be of very low safety significance, Green, because the finding did not represent an actual open pathway in the physical integrity of reactor containment and did not involve an actual reduction in function of hydrogen igniters in the reactor containment.

Cross-Cutting Aspect: H.14 - Conservative Bias: Individuals use decision-making practices that emphasize prudent choices over those that are simply allowable. A proposed action is determined to be safe in order to proceed, rather than unsafe in order to stop. Specifically, the licensee proceeded with monitoring the MSIV, instead of performing additional maintenance on the valve to reduce the leakage to within limits.

Enforcement:

Violation: The Renewed Facility Operating License for Susquehanna Steam Electric Station, Unit 1, TS 5.4.1a requires, in part, that written procedures shall be established, implemented, and maintained covering the activities of the applicable procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978, of which Section 9, Procedures for Performing Maintenance, requires maintenance that can affect the performance of safety-related equipment should be performed in accordance with written procedures.

In addition, the Renewed Facility Operating License for Susquehanna Steam Electric Station, Unit 1, TS LCO 3.6.1.3, Condition A, requires, in part, for flowpaths with one primary containment isolation valve inoperable, to isolate the affected penetration within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> for main steam lines and verify the affected penetration flow path is isolated once per 31 days or, as required by Condition G, be in Mode 3 in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and Mode 4 in 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

Contrary to the above, on April 17, 2022, the licensee failed to implement procedure NDAP-QA-0412, Leakage Rate Testing Program, Revision 24. As a result, during the operating cycle, the licensee failed to complete the required actions of TS LCO 3.6.1.3, Conditions A and G, within the required completion times.

The disposition of this finding closes LER 05000387/2024-001-00, Main Steam Isolation Valve Leakage, and LER 05000387/2024-001-01, Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear.

Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.

EXIT MEETINGS AND DEBRIEFS

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

• On October 3, 2024, the inspectors presented the biennial problem identification and resolution inspection results to Mark Jones, Senior Manager, Engineering and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

71152B

Corrective Action

Documents

CR-2023-17617

CR-2019-01780

CR-2019-11903

CR-2021-01122

CR-2021-03614

CR 2021-10267

CR-2021-14762

CR-2021-16804

CR-2022-05322

CR-2022-08555

CR-2022-08913

CR-2022-12194

CR 2022-12456

CR-2022-12458

CR 2022-12462

CR-2022-12747

CR-2022-12807

CR-2022-13633

CR-2022-13993

CR-2022-14316

CR-2022-14495

CR-2022-15314

CR-2022-15553

CR-2022-15852

CR-2022-16572

CR-2022-16629

CR-2022-18364

CR-2023-00569

CR-2023-00839

CR-2023-02002

CR-2023-02244

CR-2023-02503

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

CR-2023-03248

CR-2023-04179

CR-2023-05057

CR-2023-05406

CR-2023-05531

CR-2023-06391

CR-2023-06408

CR-2023-06944

CR-2023-08689

CR-2023-09320

CR-2023-09321

CR-2023-10634

CR-2023-10741

CR-2023-14224

CR-2023-14330

CR-2023-15911

CR-2023-16840

CR-2024-00655

CR-2024-02245

CR-2024-02384

CR-2024-02437

CR-2024-02456

CR-2024-03017

CR-2024-04915

DI-2024-01343

DI-2024-01345

DI-2024-01632

DI-2022-14196

DI-2022-13363

CR-2023-18268

CR-2022-12012

CR-2022-14178

CR-2023-03035

CR-2023-02238

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

CR-2023-00985

DI-2018-17057

DI-2020-10005

DI-2022-11938

DI-2022-12487

DI-2022-14974

DI-2022-16095

DI-2022-16732

DI-2023-02476

DI-2023-10483

DI-2023-12962

DI-2024-01326

AR-2021-01778

AR-2022-15914

AR-2022-15918

AR-2023-08208

Corrective Action

Documents

Resulting from

Inspection

AR-2024-13719

CR-2024-13748

CR-2024-13750

CR-2024-13968

CR-2024-14313

CR-2024-14314

CR-2024-14242

CR-2024-14331

DI-2024-14219

DI-2024-14350

Procedures

LS-115

Operating Experience Program

Revision 4

LS-120

Issue Identification and Screening Process

Revision 15

LS-125

Corrective Action Program

Revision 15

LS-125-1001

Root Cause Analysis Procedure

Revision 10

LS-126

Self-Assessment and Benchmarking

Revision 8

NDAP-00-0032

Human Performance HUP Standards for Error and Event

Prevention

Revision 24

NDAP-QA-0440

Control of Transient Combustible/Hazardous Materials

Revision 29

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

NDAP-QA-0503

General Housekeeping

Revision 52

Self-Assessments

23 Training & Qualifications - Operations Audit Report

AR-2021-10422

22 Engineering and Fuel Management Audit

DI-2022-11144

CISA on Effectiveness of Implementation of ER-2003,

Equipment Reliability Risk Management Process and

Associated Heat Map

OP080

Biannual - CISA Conduct of Operations