IR 05000315/2022011
ML22259A156 | |
Person / Time | |
---|---|
Site: | Cook ![]() |
Issue date: | 11/04/2022 |
From: | Karla Stoedter NRC/RGN-III/DORS |
To: | Lies Q Indiana Michigan Power Co |
Shared Package | |
ML22311A476 | List: |
References | |
IR 2022011 | |
Download: ML22259A156 (31) | |
Text
November 4, 2022
SUBJECT:
DONALD C. COOK NUCLEAR PLANT - DESIGN BASIS ASSURANCE INSPECTION (TEAMS) INSPECTION REPORT 05000315/2022011 AND 05000316/2022011
Dear Mr. Lies:
On September 21, 2022, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Donald C. Cook Nuclear Plant and discussed the results of this inspection with Mr. M. Scarpello and other members of your staff. The results of this inspection are documented in the enclosed report.
Four findings of very low safety significance (Green) are documented in this report. Four of these findings involved violations of NRC requirements. We are treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2 of the Enforcement Policy.
If you contest the violations or the significance or severity of the violations 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 III; the Director, Office of Enforcement; and the NRC Resident Inspector at Donald C. Cook Nuclear Plant. 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, Signed by Stoedter, Karla on 11/04/22 Karla K. Stoedter, Chief Engineering Branch 1 Division of Operating Reactor Safety Docket Nos. 05000315 and 05000316 License Nos. DPR-58 and DPR-74
Enclosure:
As stated
Inspection Report
Docket Numbers: 05000315 and 05000316 License Numbers: DPR-58 and DPR-74 Report Numbers: 05000315/2022011 and 05000316/2022011 Enterprise Identifier: I-2022-011-0020 Licensee: Indiana Michigan Power Company Facility: Donald C. Cook Nuclear Plant Location: Bridgman, MI Inspection Dates: June 27, 2022 to September 21, 2022 Inspectors: C. Baron, Contractor J. Corujo-Sandin, Senior Reactor Inspector B. Daley, Senior Reactor Inspector I. Hafeez, Senior Reactor Inspector M. Jones, Reactor Inspector D. Melendez-Colon, Reactor Inspector J. Park, Reactor Inspector D. Turpin, Resident Inspector Approved By: Karla K. Stoedter, Chief Engineering Branch 1 Division of Operating Reactor Safety Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a design basis assurance inspection (teams) inspection at Donald C. Cook Nuclear 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
Failure to Test Manual Valve Function in Accordance with the Inservice Test Program Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-01 Open/Closed The inspectors identified a finding of very low safety significance (Green) and a Non-Cited Violation of Title 10 of the Code of Federal Regulations (10 CFR) 50.55a, "Codes and Standards," for the licensees failure to perform periodic manual valve testing on Auxiliary Feedwater Flow Control Valves 2-FMO-211 and 2-FMO-212, as well as their sister valves, in accordance with the American Society of Mechanical Engineers (ASME) Operation and Maintenance Code (OM Code), paragraph ISTC-3540, Manual Valves. This testing is required to ensure the operational readiness of valves required to perform a specific function in shutting down, maintaining the safe shutdown condition, or in mitigating the consequences of an accident.
Failure to Correctly Determine Auxiliary Feedwater Pump Suction Low Pressure Alarm Setpoints Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-02 Open/Closed The inspectors identified a Green finding and associated Non-Cited Violation of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion III, Design Control, due to deficiencies in the analysis used to support changing the Auxiliary Feedwater pump (AFW) low suction pressure trip from automatic to manual. Specifically, the licensee failed to recognize the selected annunciator setpoint, calculated in ECP-12-F2-01, did not consider the most limiting flow condition, nor the associated limiting scenario. When these conditions were considered, the time available for operators to respond to an AFW low suction pressure condition was reduced from 14 to 17 minutes to less than 5 minutes.
Failure to Correct Condition Adverse to Quality in Test Procedure for Essential Service Water Flow Verification Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-03 Open/Closed The inspectors identified a Green finding and associated Non-Cited Violation of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XVI, Corrective Action, for the licensees failure to establish measures to assure a condition adverse to quality was corrected. Specifically, the licensee had not taken action to fully correct a violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, identified during the 2015 NRC Triennial Heat Sink Inspection. As a result, the portion of the design control violation related to design deficiencies in the Emergency Service Water flow balance test procedures remained uncorrected.
Failure to Establish and Incorporate Correct Minimum Inservice Testing Pump Performance Limits into the Essential Service Water Pump Test Acceptance Criteria Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-04 Open/Closed The inspectors identified a Green finding and associated Non-cited Violation of the Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XI, Test Control, for the licensees failure to assure that applicable regulatory requirements and acceptance limits contained in the Emergency Service Water (ESW) pumps design documents were incorporated into the ESW test procedures. Specifically, the ESW pumps' Inservice Testing (IST) comprehensive test acceptance criteria did not account for the pumps' Minimum Operability Limit established in Calculation 1-2-O1-04 CALC1, Pump Minimum Operability Limits (MOL) and Measurement Uncertainty Calculation. Because these IST results are an input into the ESW Flow verification procedures, the affected pumps could have degraded below the performance level analyzed in hydraulic calculation MD-12-ESW-111-N, "ESW Hydraulic Analyses for Replacement of CTS Heat Exchangers." Degradation below the analyzed level would prevent the ESW system from supplying the supported loads with the required design bases flows.
Additional Tracking Items
Type Issue Number Title Report Section Status URI 05000315,05000316/20 Adequacy of Mitigating 71111.21M Open 22011-05 Strategies Procedures and Training
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.
REACTOR SAFETY
===71111.21M - Design Bases Assurance Inspection (Teams) The inspectors evaluated the following components and listed applicable attributes, permanent modifications, and operating experience:
Design Review - Risk-Significant/Low Design Margin Components (IP Section 02.02)
=
For each component sample, the inspectors reviewed the licensing and design bases including:
- (1) the Updated Safety Analysis Report (USAR);
- (2) the Technical Specifications (TS); and
- (3) the Technical Requirements Manual (TRM). The inspectors reviewed a sample of operating procedures (including normal, abnormal and emergency procedures),overall system/component health (including condition reports and operability evaluations, if any) and associated maintenance effectiveness (e.g., Maintenance Rule, procedures). The inspectors performed visual inspections of the accessible components to identify potential hazards and/or signs of degradation. Additional component specific design attributes reviewed by the inspectors are listed below. Components were selected in pairs as part of an effort to identify potential common cause deficiencies.
- (1) Unit 2: Emergency Incoming Feeder Breakers from Diesel Generator 2CD (2-T21C3 and 2-T21D8)1. Modifications 2. Translation of vendor specifications 3. Environmental qualification 4. Protection against external events:
a. Fire 5. Test/inspection procedures, acceptance criteria, and recent results:
a. Load testing b. TS surveillance c. Relay calibration d. Terminal corrosion resistance and grease hardening 6. Electrical design calculations and considerations:
a. Loading calculations
- (2) Unit 2: East and West Essential Service Water Pump Discharge Strainers (2-OME-34E and 2-OME-34W)1. Modifications
2. Protection against external events:
a. Seismic 3. Mechanical design:
a. Debris loading impact to flow capacity and flow balance b. Debris loading impact to structural design c. Instrument differential pressure setpoints d. Mesh size vs. downstream component openings e. Manual backwash capability f. Pneumatic backwash compressed air capacity 4. Test/inspection procedures, acceptance criteria, and recent results
- (3) Unit 2: 4160V to 600V BUS 21B and 21D Supply Transformers (2-TR21B and 2-TR21D)1. Modifications 2. Translation of vendor specifications 3. Electrical design calculations and considerations:
a. Connections b. Temperature effects and environmental qualification c. Surge arrester protection d. Breaker settings and ratings to prevent spurious tripping e. Breaker control voltage f. Harmonic content g. Grounding h. Protective devices 4. Test/inspection procedures, acceptance criteria, and recent results:
a. TS surveillance b. Terminal corrosion resistance
Design Review - Large Early Release Frequency (LERFs) (IP Section 02.02) (1 Sample)
- (1) Unit 2: West Motor Driven Auxiliary Feedwater Pump (2-PP-3W) and Turbine Driven Auxiliary Feedwater Pump (2-PP-4) Discharge to Steam Generator 1 Control Valves (2-FMO-212 and 2-FMO-211)1. Protection against external events:
a. Seismic b. High Energy Line Break 2. Mechanical design:
a. Weak link analysis b. Required thrust (torque)c. Closure/Opening time d. Maximum allowed leakage e. Maximum differential pressure 3. Test/inspection procedures, acceptance criteria, and recent results:
a. Leakage b. Inservice testing c. TS required surveillance testing d. Leak rate testing e. Actuation testing 4. Motor power requirements:
a. Voltage drop b. Control logic c.
Load flow d.
Thermal overload e.
Required minimum voltage f.
Degraded voltage effects g.
Motor thermal overload protection h.
Protective devices i.
Battery power supply i. Battery sizing ii. Surveillances
Modification Review - Permanent Mods (IP Section 02.03) (6 Samples)
- (1) Engineering Change (EC) 54141: Replacement Relays for 2-43X-DGABCT, 2-43X1-DGABCT, and 2-43X2-DGABCT
- (2) EC 54871: 2-PP-3W-MTR - West Motor Driven Auxiliary Feedwater Pump PP-3W Motor Replacement
- (3) EC 55737: Change Ultimate Heat Sink Surveillance Temperature Limit from 88.8 degrees Fahrenheit to 86.9 degrees Fahrenheit
- (4) EC 55157: Unit 2 East Motor Driven Auxiliary Feed Pump Room Cooler Replacement
- (5) EC 57586: 2-FW-134 - Turbine Driven Auxiliary Feed Pump Suction Header Check Valve Replacement
- (6) EC 57965: Implementation of the Inservice Inspection Program Boundaries Bases
Document Review of Operating Experience Issues (IP Section 02.06) (2 Samples)
- (1) Regulatory Information Summary 2000-02: Closure of Generic Safety Issue 23 -
Reactor Coolant Pump Seal Failure
- (2) NUREG-1776: Regulatory Effectiveness of the Station Blackout Rule
INSPECTION RESULTS
Failure to Test Manual Valve Function in Accordance with the Inservice Test Program Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-01 Open/Closed The inspectors identified a finding of very low safety significance (Green) and a Non-Cited Violation of Title 10 of the Code of Federal Regulations (10 CFR) 50.55a, "Codes and Standards," for the licensees failure to perform periodic manual valve testing on Auxiliary Feedwater Flow Control Valves 2-FMO-211 and 2-FMO-212, as well as their sister valves, in accordance with the American Society of Mechanical Engineers (ASME) Operation and Maintenance Code (OM Code), paragraph ISTC-3540, Manual Valves. This testing is required to ensure the operational readiness of valves required to perform a specific function in shutting down, maintaining the safe shutdown condition, or in mitigating the consequences of an accident.
Description:
Donald C. Cook Inservice Testing (IST) Program Plan - 5th Interval, Revision 4, states the code of record for the Fifth 10-Year IST Program interval is the ASME OM Code, 2004 Edition through 2006 Addenda. The IST requirements apply, in part, to valves required to perform a specific function in shutting down the reactor to the safe shutdown condition, in maintaining the safe shutdown condition, or in mitigating the consequences of an accident.
The IST Program Plan - 5th Interval states the Auxiliary Feedwater (AFW) Control Valves 2-FMO-211 and 2-FMO-212 are ASME Class 3, Category B, normally open, active valves with a safety function both in the open and closed positions. Category B valves are those for which seat leakage in the closed position is inconsequential for fulfillment of the required function(s). For the purpose of IST, active valves are defined as those which may be required to change obturator position to accomplish their required safety function(s). The ASME OM Code-2006, paragraph ISTC-3540, states, in part, that manual valves shall be full-stroke exercised at least once every 2 years, except where adverse conditions may require the valve to be tested more frequently to ensure operational readiness, and the valve shall exhibit the required change of obturator position.
Emergency Operating Procedure (EOP) 2-OHP-4023-E-2, Faulted Steam Generator Isolation, Revision 9, provides actions to identify and isolate a faulted steam generator (SG).
Step 5, Isolate Faulted SG(s), Substep b, instructs operators to check that the AFW valves for faulted SG(s) are closed. If the valve(s) cannot be manually closed, then the procedure instructs the operators to locally close the valve(s). Valves 2-FMO-211 and 2-FMO-212, as well as the sister valves 2-FMO-221, 231, 241, 222, 232, and 242, are listed under the Response Not Obtained column of Step 5, Substep b, of Procedure 2-OHP-4023-E-2.
Procedure 1-OHP-4023-E-2 contains similar steps for the equivalent Unit 1 valves.
For the purpose of clarity, it is important to distinguish that the licensee's EOPs consider "Manually" closing a valve to be when operators remotely operate said valve from the Control Room. To "Locally" close a valve is when said action takes place in the field. However, when using ASME OM Code terminology, "Manually" operating a valve is analogous to the EOPs term "Locally."
The inspectors noted that because the 2-FMO-211 and 2-FMO-212 valves would have to be repositioned (closed) locally (i.e., ASME OM manually), using a handwheel, to perform their required safety function in the event of a faulted SG and a postulated failure of the valves to be closed from the Control Room, the valves were required to be tested in accordance with paragraph ISTC-3540 of the ASME OM Code-2006. It is important to note that the only two options discussed to isolate the flow path of the AFW Control Valves in EOP 2-OHP-4023-E-2, Step 5, Substep b, are the valve operation from the Control Room or the local manipulation. Based on the inspectors review of the IST plan and test procedures for the 2-FMO-211 and 2-FMO-212 valves, the inspectors determined the licensee failed to ensure the local function (close locally with a handwheel) credited in Procedure 2-OHP-4023-E-2, and the design bases analysis, was periodically tested using the handwheel in accordance with ASME OM Code-2006.
Based on Updated Final Safety Analysis Report (UFSAR) Section 14.3.4.4.2.3, Single Failure Effects, which addresses single failures related to postulated secondary system pipe ruptures inside containment, a single active failure of an AFW valve to change position on demand was within the stations licensing and design basis. Realignment of the AFW system to isolate flow to the faulted SG would be required to limit the mass and energy release to the containment. Because Procedure 2-OHP-4023-E-2 would direct the operators to locally close the affected valve in response to this single failure, the local function of these valves is considered a safety function requiring inclusion in the IST program.
The NRC regulations in 10 CFR 50.55a(b)(3)(ii) require licensees to comply with the provisions for testing motor-operated valves (MOVs) in the ASME OM Code, and to establish a program to ensure that MOVs continue to be capable of performing their design-basis safety functions. As incorporated by reference in 10 CFR 50.55a, ASME OM Code (2004 Edition through 2006 Addenda), Subsection ISTA, Paragraph ISTA-1100, Scope, states, in part, that the OM Code establishes requirements for preservice and inservice testing of certain components to assess their operational readiness, and that those requirements apply to pumps and valves that are required to perform a specific function in shutting down a reactor to the safe shutdown condition, in maintaining the safe shutdown condition, or in mitigating the consequences of an accident. For manually operated valves within the ISTA-1100 scope, ASME OM Code, Paragraph ISTC-3540, requires that manual valves be full-stroke exercised at least every 2 years, except where adverse conditions may require the valve to be tested more frequently to ensure operational readiness. The NRC has provided guidance for these requirements in Generic Letter (GL) 89-10; Supplements 1 and 6 to GL 89-10; GL 96-05; Federal Register notice 64 FR 51370 (September 22, 1999), and NUREG-1482, Section 2.2, Scope of Inservice Testing Programs, and Section 4.4.3.2, Power-Operated Valves with Manual Valve Capability. Therefore, the 2-FMO-211 and 2-FMO-212 valves and their Unit 1 and Unit 2 sister valves at D.C. Cook are required to meet the ASME OM Code requirements in ISTC-3540, as well as the other applicable OM Code requirements, as part of the IST program required by 10 CFR 50.55a.
Corrective Actions: On July 15, 2022, the licensee documented the inspectors' concern in their Corrective Action Program. The licensee stated that preventative maintenance activities, performed every 4 years, include engaging the MOV handwheels and verifying that they function. These activities do not include full-stroke testing and are not performed every 2 years as required by the ASME OM Code. However, the licensee stated these periodic preventative maintenance activities do provide reasonable assurance that the valves would function if required. Therefore, the inspectors did not identify any immediate operability concern.
Corrective Action References: AR 2022-5818, AFW to SG supply valve FMOs not manually stroked IAW IST Code
Performance Assessment:
Performance Deficiency: The licensees failure to perform required inservice testing for the AFW Flow Control Valves 2-FMO-211 and 2-FMO-212, as well as their sister valves, in accordance with ASME OM Code-2006, paragraph ISTC-3540, was a violation of 10 CFR 50.55a(f)(4)(ii) and a performance deficiency. Specifically, site procedures rely on the affected valves, operating in manual mode, to perform a safety function, and mitigate accidents/events described in the UFSAR. However, the licensee failed to include the manual function into the IST program and perform the required full-stroke exercise and testing.
Screening: The inspectors determined the performance deficiency was more than minor because if left uncorrected, it would have the potential to lead to a more significant safety concern. Specifically, absent NRC intervention the required testing would not occur.
Performing periodic manual full-stroke exercise of the valves ensures the operational readiness required by ASME OM Code-2006, Paragraph ISTC-3540, Manual Valves.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding screened as very low safety significance (Green) because the inspectors answered all Inspection Manual Chapter 0609 Appendix A, Exhibit 2, "Mitigating Systems Screening Questions," No.
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.
Enforcement:
Violation: 10 CFR 50.55a(f)(4)(ii) requires, in part, Inservice tests to verify operational readiness of pumps and valves, whose function is required for safety, conducted during successive 120-month intervals must comply with the requirements of the latest edition and addenda of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section 18 months before the start of the 120-month interval.
Donald C. Cook IST Program Plan - 5th Interval, Revision 4, establishes the code of record for the Fifth 10-Year IST Program interval (July 1, 2016 - June 30, 2026) as the ASME OM Code, 2004 Edition through 2006 Addenda, as incorporated by reference in 10 CFR 50.55a.
ASME OM Code-2006, Paragraph ISTC-3510, Exercising Test Frequency, states, in part, Active Category A, Category B, and Category C check valves shall be exercised nominally every 3 months, except as provided by ISTC-3520, ISTC-3540, ISTC-3550, ISTC-3570, ISTC-5221, and ISTC-5222.
ASME OM Code-2006, Paragraph ISTC-3540, Manual Valves, states Manual valves shall be full-stroke exercised at least once every 2 years, except where adverse conditions may require the valve to be tested more frequently to ensure operational readiness. Any increased testing frequency shall be specified by the Owner. The valve shall exhibit the required change of obturator position.
Contrary to the above, as of August 10, 2022, the licensees inservice tests to verify operational readiness of pumps and valves, whose function is required for safety, did not comply with the requirements of the 2004 Edition through the 2006 Addenda of the ASME OM Code as incorporated by reference in 10 CFR 50.55a for the current 10-Year IST Program interval at D.C. Cook that started on July 1, 2016. Specifically, the licensee failed to include manual valve full-stroke exercise and testing of AFW Flow Control Valves 2-FMO-211, 2-FMO-212 and their sister valves in the IST program in accordance with ASME OM Code-2006, paragraph ISTC-3540.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Failure to Correctly Determine Auxiliary Feedwater Pump Suction Low Pressure Alarm Setpoints Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-02 Open/Closed The inspectors identified a Green finding and associated Non-Cited Violation of Title 10 of the Code of Federal Regulations Part 50, Appendix B, Criterion III, Design Control, due to deficiencies in the analysis used to support changing the Auxiliary Feedwater pump (AFW)low suction pressure trip from automatic to manual. Specifically, the licensee failed to recognize the selected annunciator setpoint, calculated in ECP-12-F2-01, did not consider the most limiting flow condition, nor the associated limiting scenario. When these conditions were considered, the time available for operators to respond to an AFW low suction pressure condition was reduced from 14 to 17 minutes to less than 5 minutes.
Description:
The inspectors reviewed the basis for the AFW pumps suction low pressure alarm setpoint associated with the two motor driven auxiliary feedwater pumps (MDAFP) and the turbine driven auxiliary feedwater pump (TDAFP). The nominal setpoints values were 3.84 psig decreasing and were associated with Unit 2 Annunciator #213, Drop 17 (East MDAFP Suction Pressure Low); Annunciator #214, Drop 7 (TDAFP Suction Pressure Low); and Annunciator #214, Drop 37 (West MDAFP Suction Pressure Low). There was also a nominal 10 second time delay associated with these annunciators. The Unit 2 initiating devices were 2-CPA-245/254/255; the Unit 1 devices, annunciators, and setpoints were similar.
This setpoint value was developed by an analysis included in Engineering Control Package ECP-12-F2-01,Section III, Reference 18, Low Suction Pressure Alarm Setpoint, dated March 21, 1980. This analysis concluded the setpoint would provide an operator response time of 18.09 minutes, which, after applying the time delay, was adjusted to more than 17 minutes to respond to the annunciator(s) and ensure adequate supply of water to the AFW pumps and prevent cavitation due to low net positive suction head (NPSH). The analysis was based on three AFW pumps operating with a maximum total flow of 1800 gpm.
However, the inspectors determined a lower AFW flow would be a more limiting and more probable scenario. The scenario posed by the inspectors had not been evaluated in the existing analysis.
The inspectors noted the suction pressure setpoints were originally associated with an automatic AFW pump trip feature that was installed in 1981 in response to a Three Mile Island (TMI) action item (NUREG-0611, Recommendation GL-4). However, the automatic pump trip feature was subsequently removed in 1988. The design change used to support removing the pump trip (12-RFC-2912, Remove Automatic AFW Pump Trip, Revision 0)was based on the operators ability to monitor decreasing condensate storage tank (CST)inventory and take action to ensure an adequate supply of water to the AFW pumps. This change was addressed in a licensee letter to the NRC, AEP-NRC-0976 (ML17324A947), and the NRCs response letter dated June 20, 1986. The AEP letter stated the operators would have several indications of low level in the CST, and they would have approximately 14 minutes to respond to the lowest CST level alarm. The NRCs response stated the removal of the automatic trip function was acceptable, in part, because several indicators or alarms were available to alert the operators to take appropriate measures to ensure an adequate supply of water to the pumps.
As part of a walkdown performed during this inspection, the inspectors noticed the sensor lines associated with all the CST level instruments and alarms were located outside and were provided with freeze protection heat tracing which was not powered from a vital electric source (i.e., non-safety related). As a result of this design, the CST level instruments/alarms may not be available/reliable in the event of a loss of offsite power during cold weather. The AFW pumps are normally aligned to the CST and are required to provide water to the steam generators during a loss of offsite power event. The amount of time the level instruments would remain available/reliable without heat tracing had not been analyzed nor accounted for as part of 12-RFC-2912.
In response to this concern, the licensee stated the operators would recognize abnormal CST level indications (due to freezing) and would rely on the pumps low suction pressure alarms or local pressure indication in the AFW pump rooms. The licensee indicated the operators would act based on the pump low suction pressure alarm setpoint of 3.84 psig decreasing in accordance with Annunciator Response Procedures.
The inspectors reviewed the basis of the AFW pump low pressure alarm setpoint and determined the operators may have significantly less time available to act to protect the operating AFW pumps. The limiting time had not been determined, but a preliminary licensee analysis determined less than 5 minutes may be available under the low AFW flow conditions before exhausting the inventory in the CST. The actual available operator response time would depend on the number of pumps operating and the total AFW flow rate.
Corrective Actions: No immediate corrective actions were required because cold weather conditions were not expected to exist for several months after the issue was identified.
Therefore, the CST level instruments and alarms would be available/reliable without heat tracing. The licensee stated the need for compensatory measures would be evaluated before cold weather conditions were expected.
Corrective Action References: AR 2022-5812, ECP-12-F2-01 Does Not Evaluate Limiting Time Scenario
Performance Assessment:
Performance Deficiency: The inspectors determined that when changing the AFW pumps design bases for low suction pressure from automatic pump trip to manual actions, the licensee failed to recognize the selected annunciator setpoint, calculated in ECP-12-F2-01, did not consider the most limiting flow condition, nor the associated limiting scenario. This could reduce the available operator response time from 14 to 17 minutes down to less than 5 minutes, before exceeding the NPSH limits of the AFW pumps. This was contrary to 10 CFR, Part 50, Appendix B, Criterion III, Design Control, and was a performance deficiency.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Design Control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, these non-conservative suction pressure setpoints, in conjunction with the CST level instruments vulnerability to freezing under loss of offsite power conditions, would not provide the operators with timely indication of low CST level so action could be taken to avoid AFW pump damage. Based on informal analysis, the time available to the operators could be significantly less than the 17 minutes determined in ECP-12-F2-01 or the 14-minute value provided to the NRC when the automatic AFW pump trip feature was removed. The shorter time would result in reduced reliability for the AFW pumps.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power.
Specifically, the finding screened to Green (very low safety significance) because it did not result in the loss of operability or PRA functionality. The licensees preliminary assessment determined the current existing actions outlined in the Abnormal Operating Procedures and Annunciator Response Procedures are considered adequate for operators to respond to a loss of condensate and trip AFW pumps.
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.
Enforcement:
Violation: CFR 10 Part 50, Appendix B, Criterion III, Design Control, states, in part, measures shall be established to assure that applicable regulatory requirements and the design basis are correctly translated into specifications, drawings, procedures, and instructions.
Engineering Control Package, ECP-12-F2-01,Section III, Reference 18, Low Suction Pressure Alarm Setpoint, dated March 21, 1980, was the licensee analysis which developed the AFW Pumps' low suction pressure setpoint and concluded it would provide the operators more than 17 minutes (when connected to the CST) to respond to the annunciator(s). This would ensure an adequate supply of water to AFW pumps and prevent cavitation due to low NPSH.
Design Change 12-RFC-2912, Remove Automatic AFW Pump Trip, Revision 0, was based on the operators ability to monitor decreasing CST inventory and take action to ensure adequate supply of water to AFW pumps was maintained.
Licensee letter AEP-NRC-0976 and subsequent NRCs response letter dated June 20, 1986, discussed the removal of the automatic AFW pump trip function and the switch to a manual action strategy which relied on CST level instrumentation and AFW pumps' low suction pressure instrumentation. The low suction pressure instrumentation, as well as its power sources, were safety-related. The licensee letter also established the operators would have at least 14 minutes to respond to the lowest CST level alarm.
Contrary to the above, from June 20, 1986 to July 14, 2022, the licensee failed to assure the applicable regulatory requirements and the design bases were correctly translated into specifications, drawings, procedures, and instructions. Specifically, when changing the AFW pumps design bases for low suction pressure from an automatic pump trip to manual actions, the licensee failed to recognize the selected annunciator setpoint, calculated in ECP-12-F2-01, did not consider the most limiting flow condition, nor the associated limiting scenario. When these limitations were considered, the time available for operators to respond to an AFW low suction pressure condition was reduced from 14 to 17 minutes to less than 5 minutes.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Failure to Correct Condition Adverse to Quality in Test Procedure for Essential Service Water Flow Verification Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-03 Open/Closed The inspectors identified a Green finding and associated Non-Cited Violation of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XVI, Corrective Action, for the licensees failure to establish measures to assure a condition adverse to quality was corrected. Specifically, the licensee had not taken action to fully correct a violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, identified during the 2015 NRC Triennial Heat Sink Inspection. As a result, the portion of the design control violation related to design deficiencies in the Emergency Service Water flow balance test procedures remained uncorrected.
Description:
The NRC Triennial Heat Sink Inspection conducted in 2015 (Inspection Report 05000315/2015001; 05000316/2015001, ML15132A744) identified, in part, a 10 CFR, Appendix B, Criterion III, "Design Control," violation for the licensee's failure to verify the adequacy of the design. Specifically, the Emergency Service Water (ESW) hydraulic calculations and flow balance test procedures did not verify the performance of the system was adequate when operating with the maximum allowed strainer debris loading. The affected documents were ESW Hydraulic Calculation, MD-12-ESW-111-N, ESW Hydraulic Analyses for Replacement of CS Heat Exchangers, and ESW Flow balance procedures 1-OHP-4030-119-022FV and 2-OHP-4030-219-022FV, ESW Flow Verification.
In response to the identified violation, the licensee entered this issue into their Corrective Action Program (CAP) as Action Request (AR) 2015-1324 and AR 2015-1622. As part of the corrective action, the licensee revised Hydraulic Calculation MD-12-ESW-111-N to account for strainer loading. However, the corrective actions did not account for the effects of the strainer loading into the subsequent ESW Flow balance tests. Action Request 2015-1324 and AR 2015-1622 were closed on August 7, 2015, and January 27, 2016, respectively.
Corrective Actions: The licensee took immediate corrective action to perform a preliminary quantitative re-evaluation the ESW system flow. Additionally, the licensee provided a qualitative assessment of the inherent margins that were available in the ESW system to perform its required cooling function over the extended period of time during the accident progression to demonstrate a reasonable assurance of operability of the ESW system existed for both units.
Corrective Action References: AR 2022-5781, ESW Flow Verification Does Not Account for Maximum Strainer Differential Pressure
Performance Assessment:
Performance Deficiency: The inspectors determined the failure to correct a condition adverse to quality was contrary to 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Actions, and was a performance deficiency. Specifically, during the 2015 NRC Heat Sink Inspection, the inspectors identified that a hydraulic calculation (MD-12-ESW-111-N) and flow balance test procedures (1-OHP-4030-119-022FV and 2-OHP-4030-219-022FV) did not verify the performance of the system was adequate when operating with maximum allowed strainer debris loading. The licensee entered the inspectors' concern into the CAP as AR 2015-1324 and AR 2015-1622. The licensee failed to correct or take other corrective actions regarding the flow balance test procedures and closed AR 2015-1324 and AR 2015-1622 on August 7, 2015, and January 27, 2016, respectively.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Equipment Performance attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the failure to account for the effect of the maximum ESW strainer loading in the system's flow verification could result in the unreliability of the ESW system to provide the necessary cooling flow to the supported systems. This could prevent the affected supported systems from accomplishing their intended safety functions.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding screened as very low safety significance (Green) because it did not result in loss of operability or functionality of the Mitigating Systems. Specifically, the licensee evaluated the inherent margins available and was able to demonstrate there was a reasonable assurance of operability of the ESW system for both units.
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.
Enforcement:
Violation: Title 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Actions, requires, in part, that measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected.
Contrary to the above, since January 27, 2016, the license failed to establish measures to assure conditions adverse to quality were promptly corrected. Specifically, during the 2015 NRC Heat Sink inspection, the inspectors identified that a hydraulic calculation (MD-12-ESW-111-N) and flow balance test procedures (1-OHP-4030-119-022FV and 2-OHP-4030-219-022FV) did not verify the performance of the system was adequate when operating with the maximum allowed strainer debris loading. The licensee entered the inspectors' concern into the CAP as AR 2015-1324 and AR 2015-1622. The licensee failed to correct or take other corrective actions regarding the flow balance test procedures and closed AR 2015-1324 and AR 2015-1622 on August 7, 2015, and January 27, 2016, respectively.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Failure to Establish and Incorporate Correct Minimum Inservice Testing Pump Performance Limits into the Essential Service Water Pump Test Acceptance Criteria Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21M Systems NCV 05000315,05000316/2022011-04 Open/Closed The inspectors identified a Green finding and associated Non-cited Violation of the Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XI, Test Control, for the licensees failure to assure that applicable regulatory requirements and acceptance limits contained in the Emergency Service Water (ESW) pumps design documents were incorporated into the ESW test procedures. Specifically, the ESW pumps' Inservice Testing (IST) comprehensive test acceptance criteria did not account for the pumps' Minimum Operability Limit established in Calculation 1-2-O1-04 CALC1, Pump Minimum Operability Limits (MOL) and Measurement Uncertainty Calculation. Because these IST results are an input into the ESW Flow verification procedures, the affected pumps could have degraded below the performance level analyzed in hydraulic calculation MD-12-ESW-111-N, "ESW Hydraulic Analyses for Replacement of CTS Heat Exchangers." Degradation below the analyzed level would prevent the ESW system from supplying the supported loads with the required design bases flows.
Description:
To ensure compliance with the site's licensing and design bases, the licensee established calculation MD-12-ESW-111-N, "ESW Hydraulic Analyses for Replacement of CTS Heat Exchangers," Revision 11, to analytically demonstrate the ESW system can meet the flow requirements of the heat exchangers supplied by the ESW system during a Loss of Coolant Accident (LOCA) for Recirculation or Injection.
Procedure 2-OHP-4030-219-022FV, "ESW Flow Verification, Revision 30, was implemented to verify the ESW system flow to safety related loads complies with the requirements for LOCA mitigation. In particular Attachment 6, "West ESW Train Flow Requirements," provides the flow requirements as a function of pump strength. In order to determine the appropriate flow requirements the procedure has as an input the pump's head at 9200 gpm, in psid, from the most recent IST surveillance.
The Donald C. Cook IST Program Document - 5th Interval, Revision 4, establishes the scope and testing required to comply with the applicable American Society of Mechanical Engineers Operations and Maintenance (ASME OM) code of record and the requirements of 10 CFR 50.55a(f)(4), "Inservice testing standards requirements for operating plants." This testing is done to ensure the operational readiness of pumps and valves required to perform a specific function in shutting down, maintaining the safe shutdown condition, or in mitigating the consequences of an accident. As part of the program, IST monitors pump performance degradation. This includes differential pressure (dP) testing performed on the Essential Service Water Pumps.
During a sample review of the results from a recent U2 West ESW pump IST comprehensive pump test and the ESW Flow verification test, the inspectors noted a discrepancy regarding the referenced acceptance criteria. The pump's differential pressure acceptance criteria prescribed in the IST comprehensive pump test procedure, 2-OHP-4030-219-022W, "West Essential Service Water System Test," were established based on the data obtained during the pump preservice tests in accordance with the ASME OM Code. However, the acceptance criteria for the ESW Flow verification test procedure, 2-OHP-4030-219-022FV, were established based on the 100 percent design pump curve.
This discrepancy introduced a vulnerability which would allow the ESW pumps to degrade below the minimum design performance requirements as analyzed in Calculation MD-12-ESW-111-N. For example, if the pump curve created during the preservice test in accordance with the ASME OM Code was weaker than the 100 percent design pump curve, the maximum pump degradation of 7 percent, while allowed by the code, may not satisfy the minimum design performance limits established by the ESW hydraulic analysis.
Specifically, the licensee developed Calculation 1-2-O1-04 CALC1, Pump Minimum Operability Limits and Measurement Uncertainty Calculation, to determine the ESW pumps' MOL, which defined the minimum design differential pressure that must be developed by the ESW pumps to ensure delivery of adequate flow to the supplied loads. At the time of the inspection, for the U2 West ESW pump (2-PP-7W), the low end differential pressure acceptance criteria were 60.7 psid for the Low Alert and 59.5 psid for the Low Action.
However, these acceptance criteria were inconsistent with the MOL limit of 60.9 psid established in the calculation. Upon discovery of the discrepancy, the licensee conducted an extent of condition review of the other ESW pump tests. It was identified that a similar discrepancy in the test acceptance criteria existed in the U1 East ESW Pump (1-PP-7E). For this pump the IST Low Action Limit of 60.9 psid prescribed in the test acceptance criteria was inconsistent with the MOL of 61.3 psid determined in Calculation.
As a result of the above, at least two safety-related ESW pumps (2-PP-7W and 1-PP-7E) had non-conservative testing acceptance criteria. Based on the misapplication of the IST code allowable limits and the interdependence of the test results, the affected pumps could have been allowed to degrade below the performance analyzed in calculation MD-12-ESW-111-N, "ESW Hydraulic Analyses for Replacement of CTS Heat Exchangers."
Corrective Actions: The licensee took immediate corrective action to perform a review of the past test results to verify the pumps' performance over the last two years for both units. The licensee performed a detailed comparison of the design pump curves from Calculation MD-12-ESW-111-N and the preservice test pump curves obtained from test performed under procedures 1-OHP-4030-119-022E, 1-OHP-4030-119-022W, 2-OHP-4030-219-022E, and 2-OHP-4030-219-022W for each of the ESW pumps for both units, from which the maximum allowable pump degradation was accounted. The licensee validated the differential pressure results for the pumps had been above the IST acceptance criteria and the MOL. The licensee also performed a review of the current pump configurations (i.e., pump coupling gap settings) which could affect the pump performance. As a result of this review, it was identified the Unit 1 East and Unit 2 West ESW pumps, if needed, could be allowed to degrade below the pumps' analyzed limits. Therefore, the licensee determined there was no immediate operability concern.
Corrective Action References: AR 2022-5944, TDB-2-FIG-15-1, Test Acceptance Criteria Below the MOL AR 2022-6041, ESW Pump Degradation - IST Program VS. Analyzed Limit
Performance Assessment:
Performance Deficiency: The inspectors determined the licensee's failure to assure the testing required to demonstrate the ESW pumps would perform satisfactorily in service was identified and performed in accordance with written test procedures which incorporated the requirements and acceptance limits contained in applicable design documents was contrary to 10 CFR Part 50, Appendix B, Criterion XI, Test Control, and was a performance deficiency. Specifically, the licensee failed to account for the MOL when establishing the low end IST comprehensive pump testing differential pressure acceptance criteria for ESW pumps 1-PP-7E and 2-PP-7W. This resulted in non-conservative testing acceptance criteria.
Because these IST results are an input into the ESW Flow verification procedures, the affected pumps could have degraded below the performance level analyzed in hydraulic calculation MD-12-ESW-111-N. Degradation below the analyzed level would prevent the ESW system from supplying the supported loads with the required design bases flows.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Equipment Performance attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, if ESW pump performance was to degrade, the failure to establish correct minimum IST pump performance limits into the ESW pump test acceptance criteria could result in the inability of the ESW system to provide required cooling to the other systems and components necessary to accomplish their safety functions.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding screened as very low safety significance (Green) because it did not result in a loss of operability or functionality of the Mitigating Systems. Specifically, recent ESW pump performance was reviewed and found to be acceptable.
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.
Enforcement:
Violation: Title 10 CFR Part 50, Appendix B, Criterion XI, Test Control, requires, in part, that a test program shall be established to assure that all testing required to demonstrate that structures, systems, and components will perform satisfactorily in service is identified and performed in accordance with written test procedures which incorporate the requirements and acceptance limits contained in applicable design documents.
Calculation MD-12-ESW-111-N, "ESW Hydraulic Analyses for Replacement of CTS Heat Exchangers," Revision 11, analytically demonstrate the ESW system can meet the flow requirements of the heat exchangers supplied by the ESW system during a LOCA.
Procedures 1-OHP-430-119-022FV, "ESW Flow Verification, Revision 28, and 2-OHP-4030-219-022FV, "ESW Flow Verification, Revision 30, were implemented to verify the ESW system flow to safety-related loads complies with the requirements for LOCA mitigation.
Calculation 1-2-O1-04 CALC1, Pump Minimum Operability Limits (MOL) and Measurement Uncertainty Calculation, Revision 12, determined the ESW pumps' MOL. These are the minimum differential pressures to be developed by the ESW pumps in order to meet all the required flows to the supported loads.
The Donald C. Cook IST Program Document - 5th Interval, Revision 4, establishes the scope and testing required to comply with the applicable ASME OM code of record and the requirements of 10 CFR 50.55a(f)(4), "Inservice testing standards requirements for operating plants." This testing is conducted to ensure the operational readiness of pumps and valves required to perform a specific function in shutting down, maintaining the safe shutdown condition, or in mitigating the consequences of an accident. To accomplish this goal the IST program monitors pump performance degradation. This include differential pressure testing performed on the Essential Service Water Pumps.
Procedures 1-OHP-4030-119-022E, "East Essential Service Water System Test,"
Revision 40 and 2-OHP-4030-219-022W, "West Essential Service Water System Test,"
Revision 36 are the site procedures used to perform, among other things, the IST comprehensive pump tests for pumps 1-PP-7E and 2-PP-7W respectively. Differential pressure results from this procedure are an input into the applicable "ESW Flow Verification" procedures (e.g. 2-OHP-4030-219-022FV).
Contrary to the above, as of August 10, 2022, the licensee failed to assure the testing required to demonstrate the ESW pumps would perform satisfactorily in service was identified and performed in accordance with written test procedures which incorporated the requirements and acceptance limits contained in applicable design documents. Specifically, the licensee failed to account for the MOL when establishing the low end IST comprehensive pump testing differential pressure acceptance criteria for ESW pumps 1-PP-7E and 2-PP-7W.
This resulted in non-conservative testing acceptance criteria. Because these IST results are an input into the ESW Flow verification procedures, the affected pumps could have degraded below the performance level analyzed in hydraulic calculation MD-12-ESW-111-N.
Degradation below the analyzed level would prevent the ESW system from supplying the supported loads with the required design bases flows.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Unresolved Item Adequacy of Mitigating Strategies Procedures and Training 71111.21 (Open) URI 05000315,05000316/2022011-05 M
Description:
The Donald C. Cook Nuclear Plant's Updated Final Safety Analysis Report Section 8.7 refers to a Station Blackout (SBO) as the complete loss of alternating current (AC) electric power to the essential and non-essential switchgear buses in a nuclear power plant (i.e., loss of the off-site electric power system concurrent with a turbine trip and the unavailability of the on-site emergency AC power system). The SBO does not include the loss of available AC power to buses fed by station batteries through inverters or by alternate AC power sources, nor does it assume a concurrent single failure or a design basis accident. At the Cook Nuclear Plant, which is a two-unit nuclear station, SBO is postulated to occur in only one unit since the emergency AC power sources are not completely shared by the two units. Per the site's licensing bases, the assumed maximum duration for the SBO event is 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
In March 2011, a nuclear accident occurred at the Fukushima-Daichi plant in Japan due to an earthquake and tsunami which resulted in the complete loss of AC electric power, the loss of multiple pieces of equipment, and the inability to restore electric power to the plant. Following this event, the NRC issued Orders requiring each nuclear power plant licensee to develop strategies to mitigate a similar event commonly referred to as an Extended Loss of AC Power (ELAP) event. These mitigating strategies are commonly called FLEX strategies.
Title 10 CFR 50.155, "Mitigation of beyond-design-bases events," codified many of the post-Fukushima Orders. In particular, Section 50.155(b)(1)(i) requires licensees to develop, implement, and maintain mitigation strategies for beyond-design basis external events.
Additionally, Section 50.155(d), requires each licensee to provide for the training of personnel that perform said activities. Cook Nuclear Plant developed their FLEX mitigation strategy in part to comply with the orders now codified under 10 CFR 50.155.
During the inspection, the inspectors reviewed site procedures 1-OHP-4023-ECA-0.0 and 2-OHP-4023-ECA-0.0, "Loss of All AC Power," which contain steps to respond to, and mitigate, both an SBO event and an ELAP event. To start and successfully implement the FLEX mitigation strategies, a timely determination and declaration of an ELAP event, based upon operator judgement, is crucial. This is because there are multiple time sensitive actions (TSAs) the operators must complete for the FLEX strategies to be successful.
Step 11 of procedures 1/2-OHP-4023-ECA-0.0, directs the operators to check if power to the AC Emergency Buses can be restored within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of the SBO Event. If the operators decide power cannot be restored within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, they would move to the Response Not Obtained column of the procedure and consult with the shift manager to declare an ELAP event. Step 11 is designated as a "Continuous action step" and remains applicable throughout the execution of 1/2-OHP-4023-ECA-0.0 unless otherwise stated (i.e., operators are continuously evaluating the need to declare ELAP).
A note above Step 11 of 1/2-OHP-4023-ECA-0.0, states that the direct current (DC) bus deep load shedding must be completed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of an ELAP event. The inspectors reviewed other procedures such as 12-EHP-4075-TCA-001, "Operator Time Critical Actions," and found it stated the DC Deep Load Shed needs to be completed 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> from the Loss of AC Power rather than within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of an ELAP event. Similar inconsistent language regarding the start time of FLEX-related actions was observed for the TSA regarding Control Room and TDAFWP room temporary ventilation. These inconsistencies and discrepancies concerned the inspectors since the several TSAs needed to implement the FLEX strategies had to be completed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of a loss of AC event, yet other procedures would not direct the operators to implement the TSAs until after an ELAP event had been declared.
These inspectors discussed these discrepancies with the licensees staff. The licensee reviewed the inspectors concerns and identified a fundamental misunderstanding regarding the time available for operators to use their judgement, declare an ELAP event, and successfully implement the FLEX mitigating strategies. Specifically, licensee personnel (including all but one licensed operator) believed, based upon the incorrect understanding that an ELAP event could be declared at any time during the 4-hour SBO coping time and the mitigating strategies would be successfully implemented to ensure adequate core cooling.
This was not the case. It also appeared some of the mitigating strategies-related procedures and training activities were revised following the original inspection of the sites mitigating strategies. The inspectors identified at least two TSAs needed to be initiated earlier than previously understood or guided by procedures. The first was TSA F01, which perform the deep load shed of the 250 volts DC batteries. The licensee had previously demonstrated this action could be completed in about 34 minutes. The second was TSA F07 which directs operators to connect temporary power and fans for cooling the Control Room as well as actions to improve ventilation in the TDAFP room. For this TSA, the licensee's analysis allowed up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to complete the action. The licensee previously validated this TSA could be completed in approximately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 18 minutes.
During this inspection, the inspectors also reviewed general guidance on procedure quality, industry and NRC-specific guidance documents regarding the Mitigating Strategies, 10 CFR 50.155, and the corresponding Statements of Consideration supporting the 10 CFR 50.155 rulemaking activities. The inspectors found inconsistencies between these documents regarding the specific conditions required to be addressed by the Mitigating Strategies procedures. In addition, it was not clear whether the procedural inconsistencies discussed above and the fundamental misunderstanding of time available to declare an ELAP event and still be successful implementing the strategies constituted a violation of NRC requirements. As a result, the inspectors concluded this issue was best characterized as an unresolved item pending additional discussions with NRC headquarters staff regarding the specific of this issue and whether NRC requirements were met.
Planned Closure Actions: The inspectors planned to have additional discussions with NRC headquarters staff to gain clarity on Agency requirements, including 10 CFR 50.155 requirements, and determine whether a performance deficiency and violation of NRC requirements existed.
Licensee Actions: As a part of the corrective actions, the licensee created a contingency action for both control rooms to ensure an ELAP event would be declared once the operators reached Step 11 of procedures 1/2-OHP-4023-ECA-0.0. This would ensure FLEX actions are started within the first hour of a loss of all AC power event, and the TSAs for the deep DC load shed and the installation of temporary ventilation for the Control Room and TDAFP room would occur early enough to assure the necessary equipment would be available to maintain core cooling for the duration of the ELAP. Additionally, an action to revise procedures 1/2-OHP-4023-ECA-0.0 has been assigned to address these concerns in the future.
Corrective Action References: AR 2022-5766, ELAP declaration timing concern on Loss of AC Power
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
On July 15, 2022, the inspectors presented the Initial Technical Debrief inspection results to Ms. K. Ferneau, Site Vice President and other members of the licensee staff.
On August 9, 2022, the inspectors presented the Second Technical Debrief inspection results to Mr. J. McClelland, Managing Director of Engineering and other members of the licensee staff.
On August 10, 2022, the inspectors presented the Preliminary Exit Meeting inspection results to Ms. K. Ferneau, Site Vice President and other members of the licensee staff.
On September 21, 2022, the inspectors presented the design basis assurance inspection (teams) inspection results to Mr. M. Scarpello, Regulatory Affairs Manager and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection Type Designation Description or Title Revision or
Procedure Date
71111.21M Calculations 0025-0166-07 Evaluation of Stem Thrust Requirements for 3
1/2-FMO-211/221/231/241 & 1/2-FMO-212/222/232/242
2-E-N-ELCP- 250VDC Battery 2N System Analysis 3
250-008
1-2-O1-04 Pump Minimum Operability Limits (MOL) and Measurement 12
CALC1 Uncertainty Calculation
2-E-N-PROT- Generic Thermal Overload Heater Sizing Calculation for DC 0
TOL-DC-MOV- Motor Operated Valves Within the GL 89-10 Program
001
2-E-S-250D- 250VDC Battery Deep Load Shed (DLS) Analysis 1
FLEX-001
2-E-N-ELCP-250- Unit 2 250VDC System Coordination Study 3
001
2-E-N-ELCP- Unit 2 4 KV/600 V Load Control Calculation 19
3192C Evaluation of Stroke Time and Actuator Capability for 1
1/2-FMO-211/221/231/241 Using the BWROG DC Motor
Methodology
CN-FSB-13-13-R Reactor Coolant System (RCS) Inventory Control and 1
Long-Term Subcriticality Analysis to Support the Diverse
and Flexible Coping Strategy (FLEX)
DC-D-12-ESW-17 LBPRP Analysis of ESW Piping and Pipe Supports for 1
EBASCO Walkdown Package No. 29
MD-02-CA-010-N Backup Control Air Supply Requirements for Unit 2 ESW 0
Strainer Backwash Valves
MD-12-AFW-026- Maximum Differential Pressure During Operation of AFW 2
N Pump Discharge Valves
MD-12-ESW-111- ESW Hydraulic Analyses for Replacement CTS Heat 11
N Exchangers
MD-12-ESW-112- Impact of ESW Supply Header Crosstie Shutoff Valve 0
N Leakage on the ESW System
MD-12-HV-037-N Control Room Temperature Transient During Station 13
Inspection Type Designation Description or Title Revision or
Procedure Date
Blackout
MD-12-MSC-040- MOV Parameters Calculation for Valves 4
N
MD-2-MSC-053- DC Cook Unit 2 GL 89-10 Scope 6
N
NTS-2003-005- Structural Evaluation of DC Cook Replacement Basket 1
REP Assembly for 24-inch ESW Strainer
SD-000426-002 Support Requirements for NLI Room Coolers 7
SD-120512-001 Seismic Qualification of Matheson Pressure Regulator Valve 1
SD-170214-001 Seismic Qualification Report of MDAFP Room Coolers Per 1
PMT Nuclear Qualification Reports N2135-SEIS-1, Rev. 2
and N2135-SEIS-2, Rev. 2
SD-990825-003 HELB: Identification of Unit 2 High Energy Lines and 4
Postulation of High Energy Line Breaks
SD-990825-024 Seismic Weak Link Thrust Calculation for MOVs 2-FMO-211 2
and 2-FMO-212
SQUG-2-OME- East Essential Service Water Pump PP-7E Discharge 0
34E Strainer
SQUG-2-OME- West Essential Service Water Pump PP-7W Discharge 0
34W Strainer
TH-00-05 Auxiliary Feed Water Pump Room Heat-Up Temperatures 5
Corrective Action 00802327 Classifying ESW Strainer Backwash Safety Related 09/06/2006
Documents 05177018 Safety Classification and Seismic Qualification Basis for the 06/26/2005
Condensate Storage Tanks
2011-8553-4 Evaluate RCS Dilution Termination as TCA N/A
2012-10381 2012 CDBI Enhancement to Loss of CST Inventory 08/23/2012
Response
2012-10385 2012 CDBI - ESW to AFW Void Mod or Analysis Required 08/23/2012
2012-10519 2012 CDBI - CST Tornado Qualification Question 08/27/2012
2015-1324 Non-Conservative ESW Strainer dP Used in ESW Hydraulic 01/28/2015
Model
2015-1622 ESW Cross-Tie Valve Leakage Is Not Accounted for in 02/03/2015
Analysis
Inspection Type Designation Description or Title Revision or
Procedure Date
20-2211 WR only for Sec. Disc. Cleanings of Unit 2 4KV Cubicles 03/05/2020
20-6263 1-WRV-761 Air Line Broken 08/07/2020
20-8634 Replacement Strategy for Critical Dry Type Transformer 10/14/2020
21-2410 U2 West ESW Pp Discharge Strainer Auto Vent Trap 03/17/2021
Leaking By
21-4399 Leak by on 2-T-131-3 05/14/2021
21-4523 Extent of Condition Replacement of 2-99X-T21C3 & 05/17/2021
2-99X-T21D8
22-5417 Sealtite at Fitting Is Split/Cut on Both Sealtite/Conduits 06/28/2022
Corrective Action 2022-5424 Conduit 8744R-2 Updates for Edison Cable Database 06/28/2022
Documents 2022-5451 2022DBAI: Typo Found in EC-55737 06/29/2022
Resulting from 2022-5483 Enhancement to 4kV Calcs - Add References for MOV 06/30/2022
Inspection Classes
22-5559 Update Assumptions in 01/02-E-ELCP-250-008 07/05/2022
22-5728 Typo in DB-12-ESW for a DIT Reference 07/12/2022
22-5766 ELAP Declaration Timing Concern on Loss of AC Power 07/13/2022
22-5781 ESW Flow Verification Does Not Account for Max Strainer 07/13/2022
dP
22-5785 Removal of CST and Connected Piping from ISI Program 07/13/2022
22-5790 Calculation MD-12-ESW-112-N Methodology Error 07/13/2022
22-5811 Update DIT-B-02317-11 to Address Crosstie Valve Seat 07/14/2022
Leakage
22-5812 ECP-12-F2-01 Does Not Evaluate Limiting Time Scenario 07/14/2022
22-5818 AFW to SG Supply Valve FMOs Not Manually Stoked IAW 07/15/2022
IST Code
22-5944 TDB-2-FIG-15-1, Test Acceptance Criteria Below the MOL 07/21/2022
22-6041 ESW Pump Degradation - IST Program vs Analyzed Limit 07/26/2022
Drawings 1-2-5797-6 Essential Service Water Basket Assembly 24" AL Duplex 6
Strainer
DC-16891 Support Drawing for Left Return Water Heat Pump Vertical 1
E-1300 345/34.5KV One Line Diagram 42
OP-1-5106A Flow Diagram - Aux. Feedwater Unit 1 68
OP-2-12002-51 Main Auxiliary One- Line Diagram Bus "C" & "D" Engineered 51
Inspection Type Designation Description or Title Revision or
Procedure Date
Safety System (Train"A")
OP-2-12003 250 VDC Main One-Line Diagram Engineered Safety 38
System (Train "A, B, N & BOP")
OP-2-12065 250 VDC Main One-Line Diagram Engineered Safety 11
System (Train "N")
OP-2-12072-20 DC Aux One-Line 250V DC Bus CD Engineered Safety 20
System (Train"A")
OP-2-5106A Flow Diagram - Aux. Feedwater Unit 2 60
OP-2-5113-97 Flow Diagram Essential Service Water 97
OP-2-98032-49 Diesel Generator 2AB Excitation & Regulation and 49
Miscellaneous Elementary Diagram
OP-2-98044-59 4KV Diesel Generator 2CD A.C.B. Elementary Diagram 59
OP-2-98046-37 4KV 600V Auxiliary Transformers 21B &21D Elementary 37
Diagram Sheet 1 of 1
OP-2-98051-10 Phasing Diagram Elementary Diagram 10
OP-2-98051-15 Synchronizing Diagram 15
OP-2-98649-17 Plant Process Computer I/O Cabinet No. 07 Digital Inputs 17
Sh 2 of 2 Elementary Diagram
Engineering 12-RFC-2460 Automatic AFW Pump Trip 3
Changes 12-RFC-2912 Remove Automatic AFW Pump Trip 0
2-LDCP-5147 Essential Service Water Strainer Structural Reinforcement 1
Modification
47758 ESW Strainer Shifting and Backwash 0
54871 2-PP-3W-MTR/AFW/West Motor Driven Auxiliary Feedwater 5
Pump PP-3W Motor Replacement
55157 U2 East MDAFP Room Cooler Replacement 9
EC-0000053868 Installation of U2 Reactor Coolant Pump Generation III 1
Passive Thermal Shutdown Seals
EC-0000057965 Implementation of the Inservice Inspection Program 0
Boundaries Bases Document
EC-55737 Change Ultimate Heat Sink Temperature Limit from 88.8*F 10/11/2017
to 86.9*F
Miscellaneous Time Critical Action Validation and Verification - Maximum 02/24/2021
Time to Isolate AFW Flow to a Ruptured Steam Generator
Inspection Type Designation Description or Title Revision or
Procedure Date
ISI Program 5th Interval 5
1-2-F2-01 Feedwater Flow Instrumentation 24
10.4.82 SER Seismic Qualification of Auxiliary Feedwater System 10/04/1982
2-OHP-4023-E- Plant Specific Background Document 9
19-308885 Time Critical Validation and Verification - Establish SBO 02/18/2019
Control Room Equipment Cooling
2012-0430-02 50.50 Screen - Installation of U1 and U2 Generation III RCP 0
Passive Thermal Shutdown Seals
9.3.82 TER Seismic Qualification of Auxiliary Feedwater System 09/03/1982
AEP: NRC:00300 NRC Requirements for Auxiliary Feedwater Systems 12/11/1979
AEP: Modifications to the Auxiliary Feedwater System 03/28/1980
NRC:00307A
AEP: Implementation Plan of Regulatory Guide 1.97 Revision 3 10/05/1988
NRC:0773AB
AEP: NRC:0976 Auxiliary Feedwater System Low Suction Pressure Pump 06/13/1986
Trip
Amendment No. Changes to the Technical Specifications 10/06/1980
2/24
CEEQ-EQ-0620 Basis for EQ of Equipment 1
Excerpt
DB-12-AFWS Design Basis Document for the Auxiliary Feedwater System 11
DB-12-ESW Design Basis Document for the Essential Service Water 19
System
DIT-B-01061-14 EOP Operator Action Times from Accident Analysis 02/09/2012
DIT-B-02317-11 ESW Flow Verification Test Target Flows for 06/27/2019
1-OHP-4030-119-022FV & 2-OHP-4030-219-022FV
EC 0000054141 Replacement Relays for 2-43X-DGABCT, 2-43X1-DGABCT, 0
and 2-43X2-DGABCT
EC-0000055589 Unit 1 AB Diesel Generator Agastat Relay Replacement 0
ECP-12-F2-01 Low Suction Pressure Alarm Setpoint 03/21/1980
Section III
Reference 18
GT-2016-0604-7 FLEX TSA Validation 03/24/2016
Inspection Type Designation Description or Title Revision or
Procedure Date
NA 2-BATT-N Factory Acceptance Test 02/02/2018
NRC Letter Response to AEP: NRC:0976 06/20/1986
NRC Letter Reliability of Auxiliary Feedwater Systems 06/16/1981
PWROG-17042- Procedure Usage Standard for Response to Plant 0
NP Transients
Specification No. Motor Driven Auxiliary Feedwater Pump Rooms - Fan Coil 0
ES-HVAC-0810- Unit Room Cooler Procurement Requirements
QCN
Procedures 1-OHP-4023- Loss of AC Power 45
ECA-0-0
1-OHP-4024-114 Annunciator #114 Response: Steam Generator 3 and 4 21
1-OHP-4030-119- East Essential Service Water System Test 40
2E
1-OHP-5030-119- ESW To Aux Feed Pump Cleanout Connection Flush 9
003
2-EHP-4075- Operator Time Critical Actions 17
TCA-001
2-IHP-5030- Limitorque Valve Operator Preventive Maintenance 44
EMP-001
2-IHP-5040- Plant Winterization and De-Winterization 25
EMP-004
2-OHL-4030- Outside Heat Trace Surveillance 7
SOM-016
2-OHP-4021- Operation of the Essential Service Water System 75
019-001
2-OHP-4027- Flex Equipment Staging 6
FSG-501
2-OHP-4022-055- Loss of Condensate to Auxiliary Feedwater Pumps 19
003
2-OHP-4023-E-0 Reactor Trip or Safety Injection 46
2-OHP-4023-E-2 Faulted Steam Generator Isolation 9
2-OHP-4023-E-3 Steam Generator Tube Rupture 25
2-OHP-4023- Loss of all AC Power 45
ECA-0-0
Inspection Type Designation Description or Title Revision or
Procedure Date
2-OHP-4023- Loss of all AC Power Recovery Without SI Recovered 19
ECA-0-1
2-OHP-4024-204 Annunciator #204 Response: Essential Service Water and 43
Component Cooling
2-OHP-4024-207 Annunciator #207 Response Reactor Coolant 41
2-OHP-4024-213 Annunciator #213 Response: Steam Generator 1 and 2 17
2-OHP-4024-214 Annunciator #214 Response: Steam Generator 3 and 4 19
2-OHP-4024-216 Annunciator #216 Response: Condensate 43
2-OHP-4027- ELAP Power Management 5
FSG-4
2-OHP-4030-219- ESW Flow Verification 32
2FV
2-OHP-4030-219- West Essential Service Water System Test 38
2W
2-OHP-4030-256- Main and Auxiliary Feedwater Shutdown Testing 25
017CS
2-OHP-5030-219- ESW To Aux Feed Pump Cleanout Connection Flush 10
003
26074901 2-TR21D Clean/ Inspect & Test Transformer 01
OHI-4023 Abnormal Emergency Procedure User's Guide 48
PMP-4023-EOP- EOP Maintenance 17
001
PMP-4023-EOP- EOP/AOP/NFPA-805 Writer's Guide 8
2
PMP-4075-TCA- Time Critical Action Validation and Verification 21
001
Work Orders 55414297 12-BKR-6025 PM TO REFURB BREAKER 01
55468132-01 Modified Performance Test 10/13/2016
55497777-08 Modified Performance Test 03/15/2018
55516128 MTE 2-TR21B, Clean & Perform Core-to-GND Insulation 01
Level Test
55520716-01 Service Test 10/17/2019
55525531-01 2-WMO-704 Ultrasonic Test Adjacent Piping 02/11/2020
55526810-01 2-OME-34W, Disassemble/Inspect Strainer Internals 03/11/2020
Inspection Type Designation Description or Title Revision or
Procedure Date
55527680-01 2-OME-34E, Clean and Inspect Strainer Internals 06/17/2020
55538090-01 Modified Performance Test 04/24/2021
55543899-01 U2 West ESW Train Flow Verification 04/30/2021
55543919-01 U2 East ESW Train Flow Verification 05/10/2021
55557144-01 U1 West ESW Train Flow Verification 05/07/2022
55557248-01 U1 East ESW Train Flow Verification 04/20/2022
55558744 Unit 2 West ESW Group A Pump Test 03/16/2022
28