IR 05000277/2021002
| ML21216A057 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 08/04/2021 |
| From: | Jon Greives NRC/RGN-I/DORS |
| To: | Rhoades D Exelon Generation Co LLC, Exelon Nuclear |
| Greives J | |
| References | |
| IR 2021002 | |
| Download: ML21216A057 (15) | |
Text
August 4, 2021
SUBJECT:
PEACH BOTTOM ATOMIC POWER STATION, UNITS 2 AND 3 -
INTEGRATED INSPECTION REPORT 05000277/2021002 AND 05000278/2021002
Dear Mr. Rhoades:
On June 30, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Peach Bottom Atomic Power Station, Units 2 and 3. On July 16, 2021, the NRC inspectors discussed the results of this inspection with Mr. Matthew Herr, Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
No findings or violations of more than minor significance were identified during this inspection.
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, Jonathan Digitally signed by Jonathan E. Greives E. Greives Date: 2021.08.04 08:49:39 -04'00'
Jonathan E. Greives, Chief Projects Branch 4 Division of Operating Reactor Safety Docket Nos. 05000277 and 05000278 License Nos. DPR-44 and DPR-56
Enclosure:
As stated
Inspection Report
Docket Numbers: 05000277 and 05000278 License Numbers: DPR-44 and DPR-56 Report Numbers: 05000277/2021002 and 05000278/2021002 Enterprise Identifier: I-2021-002-0024 Licensee: Exelon Generation Company, LLC Facility: Peach Bottom Atomic Power Station, Units 2 and 3 Location: Delta, PA 17314 Inspection Dates: April 1, 2021 to June 30, 2021 Inspectors: S. Rutenkroger, Senior Resident Inspector P. Boguszewski, Senior Resident Inspector J. Brand, Reactor Inspector T. Corcoran, Project Engineer T. Fish, Senior Operations Engineer T. Hedigan, Operations Engineer Approved By: Jonathan E. Greives, Chief Projects Branch 4 Division of Operating Reactor Safety Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Peach Bottom Atomic Power Station,
Units 2 and 3, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations
No findings or violations of more than minor significance were identified.
Additional Tracking Items
None.
PLANT STATUS
Unit 2 began the inspection period at rated thermal power (RTP). On May 17, 2021, the unit was down powered to 9 percent for work inside the drywell that identified and repaired two conditions: nitrogen leakage from the instrument gas system and an increasing unidentified leak rate. The unit was returned to RTP on May 19, 2021. The unit was down powered to 70 percent for a follow-up control rod pattern adjustment on May 20, 2021, and returned to 100 percent RTP the following day. The unit remained at or near RTP for the remainder of the inspection period.
Unit 3 began the inspection period at RTP. On April 16, 2021, the unit was down powered to 53 percent for a control rod pattern adjustment, main turbine valve testing, and waterbox cleaning.
The unit was returned to RTP the following day. On May 15, 2021, the unit was down powered to 68 percent for a control rod pattern adjustment and main turbine valve testing. The unit was returned to RTP the following day. On June 12, 2021, the unit was down powered to 68 percent for a control rod pattern adjustment, main turbine bypass valve exercising, and restoration of two hydraulic control units following maintenance. The unit was restored to RTP the following day. The unit remained at or near RTP for the remainder of the inspection period.
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.
Starting on March 20, 2020, in response to the National Emergency declared by the President of the United States on the public health risks of the coronavirus (COVID-19), resident and regional inspectors were directed to begin telework and to remotely access licensee information using available technology. During this time, the resident inspectors performed periodic site visits each week, increasing the amount of time on site as local COVID-19 conditions permitted.
As part of their onsite activities, resident inspectors conducted plant status activities as described in IMC 2515, Appendix D; observed risk significant activities; and completed on site portions of IPs. In addition, resident and regional baseline inspections were evaluated to determine if all or a portion of the objectives and requirements stated in the IP could be performed remotely. If the inspections could be performed remotely, they were conducted per the applicable IP. In some cases, portions of an IP were completed remotely and on site. The inspections documented below met the objectives and requirements for completion of the IP.
REACTOR SAFETY
71111.01 - Adverse Weather Protection
Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal hot temperatures for the following systems: emergency diesel generators (EDGs), station emergency batteries, 4kV switchgear rooms, control room, and drywell chillers as of June 10, 2021
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (3 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Unit 3 'A' residual heat removal (RHR) during Unit 3 'B' RHR testing and maintenance on April 26, 2021
- (2) Unit 2 high-pressure coolant injection (HPCI) during Unit 2 reactor core isolation coolant (RCIC) maintenance on June 1, 2021
June 11, 2021 Complete Walkdown Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated system configurations during a complete walkdown of the Unit 3 RCIC during the weeks of May 10 and May 31, 2021
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (5 Samples)
The inspectors evaluated the implementation of the fire protection program by conducting a walkdown and performing a review to verify program compliance, equipment functionality, material condition, and operational readiness of the following fire areas:
- (1) PF-132, Unit common diesel generator building, general area on April 1, 2021
- (2) PF-57, Unit 2 refuel floor on April 15, 2021
- (3) PF-78H, Unit common cable spreading and computer rooms on May 12, 2021
- (4) PF-127, Unit 2 turbine building, emergency battery and switchgear rooms, elevation 135' on June 23, 2021
- (5) PF-132, Unit common diesel generator building, general area on June 23, 2021
71111.06 - Flood Protection Measures
Inspection Activities - Internal Flooding (IP Section 03.01) (1 Sample)
The inspectors evaluated internal flooding mitigation protections in the:
- (1) Unit 2 RCIC room on June 25, 2021
71111.11A - Licensed Operator Requalification Program and Licensed Operator Performance
Requalification Examination Results (IP Section 03.03) (1 Sample)
- (1) The inspectors reviewed and evaluated the licensed operator examination failure rates for the requalification annual operating exam administered on April 6, 2021
71111.11B - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Requalification Program (IP Section 03.04) (1 Sample)
- (1) Biennial Requalification Written Examinations The inspectors evaluated the quality of the licensed operator biennial requalification written examination administered in March 2020 Annual Requalification Operating Tests The inspectors evaluated the adequacy of the facility licensees annual requalification operating test administered in March 2021 Administration of an Annual Requalification Operating Test The inspectors evaluated the effectiveness of the facility licensee in administering requalification operating tests required by 10 CFR 55.59(a)(2) and that the facility licensee is effectively evaluating their licensed operators for mastery of training objectives Requalification Examination Security The inspectors evaluated the ability of the facility licensee to safeguard examination material, such that the examination is not compromised Remedial Training and Re-examinations The inspectors evaluated the effectiveness of remedial training conducted by the licensee, and reviewed the adequacy of re-examinations for licensed operators who did not pass a required requalification examination Operator License Conditions The inspectors evaluated the licensees program for ensuring that licensed operators meet the conditions of their licenses Control Room Simulator The inspectors evaluated the adequacy of the facility licensees control room simulator in modeling the actual plant, and for meeting the requirements contained in 10 CFR 55.46 Problem Identification and Resolution The inspectors evaluated the licensees ability to identify and resolve problems associated with licensed operator performance
71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01)
(1 Sample)
- (1) The inspectors observed and evaluated licensed operator performance in the main control room during preparations for a Unit 2 drywell entry, including a power reduction to 10 percent, on May 17, 2020, and again during EDG testing on June 29, 2021
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated licensed operator requalification training in the simulator on April 19, 2021
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (2 Samples)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components remain capable of performing their intended function:
- (1) Unit common, 'E-4' EDG as of April 26, 2021
- (2) Unit common, power supply inverters as of June 10, 2021
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (6 Samples)
The inspectors evaluated the accuracy and completeness of risk assessments for the following planned and emergent work activities to ensure configuration changes and appropriate work controls were addressed:
- (1) Unit 2 RCIC planned maintenance on April 6, 2021
- (2) Unit 3 RCIC planned maintenance on April 7, 2021
- (3) Unit 2 HPCI planned maintenance on April 12, 2021
- (4) Unit 3 'A' RHR heat exchanger planned cleaning and maintenance on April 19, 2021
- (5) Unit 2 emergent HPCI flow controller inverter failure on April 30, 2021
- (6) Unit 2 emergent 'K' safety-relief valve maintenance on May 18, 2021
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (4 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Unit 2 high-pressure service water (HPSW) RHR heat exchanger outlet valve junction box supported only by attached conduit on March 30, 2021
- (2) Unit common, reactor building water curtain fire systems' automatic actuation circuits were not being properly tested during surveillance testing identified on April 14, 2021
- (3) Unit common, HPSW hangers with gaps identified between the hanger shims and the piping on May 10 and 11, 2021
- (4) Unit 3 RCIC with degraded support spring can on May 11, 2021
71111.18 - Plant Modifications
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)
(2 Samples)
The inspectors evaluated the following temporary or permanent modifications:
- (1) Unit common, 'E-4' EDG's emergency service water pipe flexible expansion joints engineering change evaluation of dimensions as of April 14, 2021
- (2) Modification that installed steel reinforcing angles for seismic restraint with respect to Unit 2 masonry wall 'BW-76.8' as of May 5, 2021
71111.19 - Post-Maintenance Testing
Post-Maintenance Test Sample (IP Section 03.01) (9 Samples)
The inspectors evaluated the following post-maintenance test activities to verify system operability and functionality:
- (1) Unit 3 RCIC remote shutdown panel after inverter failure and replacement on April 7, 2021
- (2) Unit 3 'A' RHR heat exchanger testing after planned maintenance and cleaning on April 19 through April 22, 2021
- (3) Unit common, 'E-323' breaker testing after replacement on April 28, 2021
- (4) Unit 2 HPCI flow controller inverter testing after replacement on April 30, 2021
- (5) Unit common, high-pressure lube water pump pressure switch replacement and testing on May 5, 2021
- (6) Unit 2 RCIC system testing following planned system maintenance activities, including inverter replacement and value work on June 3, 2021
- (8) Unit common, 'E-3' EDG testing following scheduled maintenance overhaul on June 27, 2021
- (9) Unit 3 RCIC support spring can after repair on June 28, 2021
71111.22 - Surveillance Testing
The inspectors evaluated the following surveillance tests:
Surveillance Tests (other) (IP Section 03.01)
- (1) Unit common, 'E-2' EDG slow start full load surveillance test on April 28, 2021
- (2) Unit 2 RHR alternate shutdown panel testing on April 29, 2021
- (3) Unit 3 RCIC pump, valve, and flow on June 15, 2021
71114.06 - Drill Evaluation
Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated a limited scope emergency preparedness drill conducted on June 25,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) ===
- (1) Unit 2 April 1, 2020 to March 31, 2021
- (2) Unit 3 April 1, 2020 to March 31, 2021
BI02: RCS Leak Rate Sample (IP Section 02.11) (2 Samples)
- (1) Unit 2 April 1, 2020 to March 31, 2021
- (2) Unit 3 April 1, 2020 to March 31, 2021
71152 - Problem Identification and Resolution
Semi-annual Trend Review (IP Section 02.02) (1 Sample)
- (1) The inspectors conducted a semi-annual trend review by evaluating sample issues that occurred in the first and second quarters of 2021. During the evaluation, the inspectors verified the issues identified were addressed within the scope of the corrective action program (CAP)
Annual Follow-up of Selected Issues (IP Section 02.03) (1 Sample)
The inspectors reviewed the licensees implementation of its CAP related to the following issues:
- (1) Fire penetration seals issues
71153 - Follow Up of Events and Notices of Enforcement Discretion Personnel Performance (IP Section 03.03)
- (1) The inspectors evaluated a declared unusual event due to the existence of smoke in the Unit 2 drywell and personnel unable to verify that no fire existed within 30 minutes and the licensees subsequent performance on May 17,
INSPECTION RESULTS
Observation: Fire Penetration Seals Issues 71152 The inspectors reviewed Condition Reports 04312522, 04195447, and 04310888 which document Exelons evaluation, extent of condition reviews, and corrective actions associated with fire penetration seals inspection deficiencies identified by their nuclear oversight (NOS)personnel during routine internal reviews of fire seals inspections per station procedures ST-M-037-311-2 and 3, "Detailed Visual Inspection of Fire Penetration Seals. The inspectors focused on Exelons planned and/or implemented corrective actions to determine whether they were commensurate with the safety significance of the problems. The NOS findings which were initially identified on November 15, 2018 (AR 04195447), involved a review of the Peach Bottom Unit 2 fire penetration seals surveillance inspections completed in August 2018. Specifically, NOS identified documentation and tracking errors of numerous fire penetration seals that were inaccessible and could not be inspected, as well as other inspection documentation errors and the failure to resolve missing and incorrect information in the penetration Component Record List. Additionally, in January 2020, NOS review of the Peach Bottom Unit 3 draft surveillance procedure resulted in identification of errors in the surveillance tracking tool used as a basis for the inspection procedure. As a result, 21 penetration seals were identified to be beyond the specified inspection frequency (AR 04310888). On January 24, 2020, NOS issued an elevated finding (AR 04312522) for continued lack of rigor and low sense of urgency to address indications of non-compliance with procedural requirements that contributed to on-going fire penetration seals inspection implementation gaps.
Exelons evaluation determined there were several causal factors that resulted in the deficiencies identified by NOS. These included deficiencies in the inspection scoping process (which was maintained manually and without peer reviews), documentation errors in completed inspection records, and incorrect equipment database.
The inspectors review of corrective actions noted that Exelon staff formed a cross-discipline fire penetration seals recovery team comprised of design engineers, site and corporate fire protection program engineers, and maintenance to work through recovery actions and extent of condition reviews to address all the deficiencies identified by NOS. The inspectors reviewed the associated ARs and NOS information to assess whether the issue was accurately documented, evaluated, and to verify corrective actions have been timely and adequate. The inspectors also reviewed the engineering assessment to validate the assumptions and conclusions were supported, interviewed personnel including the fire protection system engineer, the mechanical design engineer, and the fire protection program manager, and performed independent fire seals inspections in safety-related areas of both Units 2 and 3 including; the switch gear rooms, battery rooms, cable spreading rooms, and the EDG rooms. No walkdown seal issues of significance were identified. The inspectors concluded the issue that resulted in the NOS findings were evaluated sufficiently to identify the causes and develop effective corrective actions, and that the extent of condition reviews were adequate. The inspectors also noted NOS performed a final review of the corrective actions implemented and closed out their findings on March 2, 2020. Corrective actions included: extent of condition reviews, employee training, complete re-baseline of the fire penetration seals inspection program, re-evaluation and creation of a new seal data base which included removal of all penetration seals determined to be inaccessible, revision of procedures to properly include the new list of all seals required to be inspected, and inspection of seals identified as not inspected. The inspectors did not identify any findings of more than minor significance.
Observation: 71152 Semi-Annual Trend Review 71152 The inspectors conducted a semi-annual trend review by evaluating a sample of issues that occurred in the first and second quarters of 2021. During the evaluation, the inspectors verified the issues identified were addressed within the scope of the CAP. The inspectors reviewed health reports and related databases for trends and considered prior issues while performing routine walkdowns and attending the plan of the day meetings. No substantive adverse performance trends or repetitive equipment failures were identified during this time.
However, the inspectors' trend review noted some equipment failures during the quarter with similarity and overlapping risk. In particular, there were two failures of power supply inverters during the period, one in the Unit 3 RCIC system and one in the Unit 2 high-pressure injection system, and a failure of nitrogen supply to the Unit 2 71K safety-relief valve due to hose fretting. The inspectors noted that aggregate equipment failures can represent greater cumulative combined risk relative to the simple sum of the risk from individual events. As a result, systems and components may warrant additional focus to improve maintenance effectiveness when considering these impacts. Exelon's evaluations were not yet complete at the end of the quarter. However, the inspectors reviewed Exelons initially planned actions and confirmed that the planned evaluations were robust, manufacturer and/or laboratory inputs were sought, the immediate corrective actions were appropriate, and effectiveness reviews were included when warranted.
The inspectors also observed a number of issues in the plant that was higher than recent prior periods. The inspectors shared an observation with Exelon that many of the issues were reasonably identifiable by their staff during routine activities. As one example, the inspectors identified a step-ladder designated for emergency use only, via an attached placard, which had been removed from its storage location and left setup in a standing position in a normally traversed room. The condition represented multiple breakdowns in Exelon's processes: a failure to adhere to the posted signage by using the ladder, a failure to adhere to station procedures to take down the ladder and lay it down and/or restrain it when not in use, a failure to adhere to station procedures to return the ladder to an approved storage location when work at the jobsite was complete, and a failure of personnel traversing through the room to question the ladder being upright and unattended for a period of time and still displaying the placard designating the ladder for emergency use only. The inspectors determined that all of the issues were of minor safety significance with no adverse impact to a cornerstone objective. However, the inspectors shared an observation regarding the potential for an adverse trend in a lack of attention to detail and non-compliance with procedures. In addition to addressing the individual issues, Exelon initiated an issue report to document a potential emerging trend and perform an analysis in order to improve station performance.
Exelon also issued site-wide communications and engaged supervisors and staff to improve performance. The inspectors noted improved performance afterwards.
Based on the overall results of the semi-annual trend review, the inspectors determined that Exelon had identified adverse trends at Peach Bottom Atomic Power Station before they could become more significant safety problems. The inspectors continue to monitor the CAP and maintenance effectiveness during routine inspection activities.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On July 16, 2021, the inspectors presented the integrated inspection results to Mr. Matthew Herr, Site Vice President, and other members of the licensee staff.
- On May 26, 2021, the inspectors presented the PI&R Sample, Fire Penetration Seals Issues inspection results to Mr. Mark Parrish, Design Engineering Manager Lead, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection Type Designation Description or Title Revision or
Procedure Date
71111.04 Corrective Action 04422956
Documents 04426956
04428901
Procedures M-359 RCIC System Revision 50
SO 13.1.A-3 COL RCIC System Revision 17
SO 13.1.B-3 COL RCIC System Control Board Lineup Revision 3
71111.05 Procedures PF-127 Unit 2 Turbine Building, Emergency Battery Switchgear Revision 11
Rooms, Elevation 135'0"
PF-132 Diesel Generator Building, General Area, Elevation 127'0" Revision 9
PF-78H Turbine Building Common, Cable Spreading and Computer Revision 9
Rooms
71111.06 Corrective Action 4424351
Documents
Miscellaneous EC 634394
Procedures AO 20A.1 Temporary Removal and Installation of Flood Barriers on the Revision 18
Reactor Building Drainage System
71111.15 Corrective Action 4422956
Documents 4416510
22713
22952
Corrective Action 04412724
Documents
Resulting from
Inspection
Miscellaneous EC 634268
71111.18 Calculations 87RE/CONN Design of Additional Support for the Connection Between Revision 3
Block Wall and Concrete Wall
Corrective Action 4422138
Documents
Miscellaneous EC 624203, XJ- Exp. Joint Misalign Measurement Out of Tolerance Revision 0
70133D/134D
71111.19 Corrective Action 4431791
Inspection Type Designation Description or Title Revision or
Procedure Date
Documents 4431792
4431794
Procedures RT-O-052-253-2 'E-3' Diesel Generator Inspection Post-Maintenance Revision 44
Functional Test
Work Orders 04325592
05120294
05124552
05126927
5136414
71111.22 Work Orders 5128336
71114.06 Procedures EP-AA-1007, Emergency Action Levels for Peach Bottom Atomic Power Revision 9
Addendum 3 Station
71152 Corrective Action 04195447
Documents 04310888
04312522
04378513
Corrective Action 04421136
Documents 04422880
Resulting from 4395106
Inspection 4399049
4401017
4405806
4410976
4413233
20472
20571
26780
28531
28772
4430092
Miscellaneous Technical Justification for not Inspecting Inaccessible Penetration Seals 01
Evaluation
291255-01
13