IR 05000346/2021002: Difference between revisions

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{{#Wiki_filter:August 12, 2021
 
==SUBJECT:==
DAVIS-BESSE NUCLEAR POWER STATION - INTEGRATED INSPECTION REPORT 05000346/2021002 AND 07200014/2021001
 
==Dear Mr. Brown:==
On June 30, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Davis-Besse Nuclear Power Station. On July 27, 2021, the NRC inspectors discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.
 
One Severity Level IV violation without an associated finding is documented in this report. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.
 
No NRC-identified or self-revealing findings were identified during this inspection.
 
If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:
Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; the Director, Office of Enforcement; and the NRC Resident Inspector at Davis-Besse Nuclear Power Station. 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 Dickson, Billy on 08/12/21 Billy C. Dickson, Jr., Chief Branch 2 Division of Reactor Projects Docket No. 05000346; 07200014 License No. NPF-3
 
===Enclosure:===
As stated
 
==Inspection Report==
Docket Number: 05000346; 07200014 License Number: NPF-3 Report Number: 05000346/2021002 AND 07200014/2021001 Enterprise Identifier: I-2021-002-0078 Licensee: Energy Harbor Nuclear Corp.
 
Facility: Davis-Besse Nuclear Power Station Location: Oak Harbor, OH Inspection Dates: April 01, 2021 to June 30, 2021 Inspectors: R. Cassara, Resident Inspector J. Cassidy, Senior Health Physicist J. Dalzell, Project Engineer R. Edwards, Senior Health Physicist D. Mills, Senior Resident Inspector R. Ruiz, Project Engineer Approved By: Billy C. Dickson, Jr., Chief Branch 2 Division of Reactor Projects Enclosure
 
=SUMMARY=
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Davis-Besse Nuclear Power Station, 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===
 
Spent Fuel Storage Cask Design Changes Cornerstone          Severity                                  Cross-Cutting    Report Aspect            Section Not Applicable        Severity Level IV                          Not Applicable    60855 NCV 05000346/2021002-01 Open/Closed The inspectors identified a Severity Level IV Non-Cited Violation (NCV) of Title 10 of the Code of Federal Regulations (CFR) 72.48(d)(1), Changes, Tests, and Experiments, for failing to maintain a record of a change to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to 10 CFR 72.48(c)(2). Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus potentially impact the analyzed fuel cladding temperatures, which consistent with NRC endorsed industry guidance, would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed. Additionally, in the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the supporting adiabatic heat up calculation, which differed from the ANSYS Fluent models in the NUHOMS EOS Updated Final Safety Analysis Report (UFSAR), was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.
 
===Additional Tracking Items===
Type        Issue Number              Title                          Report Section    Status URI        05000346/2019004-01        Unresolved Item Regarding      60855              Closed Peak Fuel Clad Temperature During Vacuum Drying of Canister 9
 
=PLANT STATUS=
 
Unit 1 began the inspection period at rated thermal power. On May 21, 2021, the unit was down powered to 40 percent to perform scheduled testing of the turbine stop valves. The unit was returned to rated thermal power on May 22, 2021 and remained at or near rated thermal power 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==
 
===Impending Severe Weather Sample (IP Section 03.02) (1 Sample)===
: (1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from high lake levels and localized flooding in the area surrounding the plant due to heavy rain and high winds during the week ending June 1, 2021.
 
==71111.04 - Equipment Alignment==
 
===Partial Walkdown Sample (IP Section 03.01) (2 Samples)===
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
: (1) Emergency diesel generator train 1 during the week ending May 22, 2021
: (2) Station blackout diesel generator during the week ending June 26, 2021
 
==71111.05 - Fire Protection==
 
===Fire Area Walkdown and Inspection Sample (IP Section 03.01) (4 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) Control room and adjacent support rooms, fire area FF during the week ending May 22, 2021
: (2) Service water pipe tunnel, fire area BG during the week ending June 12, 2021
: (3) Auxiliary feed pump 2 room, fire area F during the week ending June 26, 2021
: (4) Service water pump area and diesel fire pump area, rooms 51 and 52, fire area BF during the week ending June 26, 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 (SSCs) remain capable of performing their intended function:
: (1) PT-RCA1 reactor coolant system pressure transmitter replacement during the week ending May 29, 2021
: (2) Station blackout diesel generator license renewal maintenance during the week ending June 12, 2021
 
===Quality Control (IP Section 03.02) (1 Sample)===
The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:
: (1) Emergency diesel generator 1 voltage regulator reference adjuster replacement during the week ending June 26, 2021
 
==71111.13 - Maintenance Risk Assessments and Emergent Work Control==
 
===Risk Assessment and Management Sample (IP Section 03.01) (5 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) Elevated risk due to downpower to 40 percent for turbine stop valve testing during the week ending May 22, 2021
: (2) Elevated risk during emergent work in containment to replace PT-RC2A1 reactor coolant system pressure transmitter during the week ending May 29, 2021
: (3) Elevated risk while emergency diesel generator 1 inoperable due to failed field flash switch during the week ending May 29, 2021
: (4) Elevated risk during period of high winds and rain causing local flooding during the week ending May 29, 2021
: (5) Elevated risk due to the failure of emergency diesel generator 1 voltage regulator reference adjuster during the week ending June 26, 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) Component cooling water train 2 ventilation damper malfunction, CR 2021-04374
: (2) Cycle 22 1/8 core location H14 max-segment peaking deviation approaching BMAC limit, CR 2021-04524
: (3) EDG 1 failed to reach required voltage and frequency during the 184-day test, CR 2021-04282
: (4) EDG 1 overvoltage during monthly run, CR 2021-04913
 
==71111.18 - Plant Modifications==
 
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)
(1 Sample)
The inspectors evaluated the following temporary or permanent modifications:
: (1) Installation of constant level oilers on decay heat pump 1 during the week ending May 29, 2021
 
==71111.19 - Post-Maintenance Testing==
 
===Post-Maintenance Test Sample (IP Section 03.01) (3 Samples)===
The inspectors evaluated the following post-maintenance test activities to verify system operability and functionality:
: (1) Emergency diesel generator train 1 following replacement of field flash selector switch during the week ending May 29, 2021
: (2) Emergency diesel generator train 1 following replacement of voltage regulator reference adjuster during the week ending July 3, 2021
: (3) Personnel hatch local leak rate testing following containment entry during the week ending May 29, 2021
==71111.22 - Surveillance Testing==
 
The inspectors evaluated the following surveillance tests:
 
===Surveillance Tests (other) (IP Section 03.01)===
{{IP sample|IP=IP 71111.22|count=2}}
: (1) Emergency diesel generator 2 testing during the week ending June 5, 2021
: (2) Channel functional test of reactor coolant pump monitor to steam feed rupture control system channel 1 and reactor protection system channel 1 during the week ending June 19,
 
==RADIATION SAFETY==
 
==71124.02 - Occupational ALARA Planning and Controls==
 
===Radiological Work Planning (IP Section 03.01) (4 Samples)===
The inspectors evaluated the licensees radiological work planning for the following work activities.
: (1) Repair/Replace Gasket on the Cavity Nuclear Instrumentation (NI) Covers under Radiation Work Permit (RWP) 120-5115
: (2) Insulation Work Activities in Containment under Radiation Work Permit (RWP)120-5016
: (3) Contractor Services Activities in Containment under Radiation Work Permit (RWP)120-5032
: (4) Under Vessel Inspections Following NI Covers under Radiation Work Permit (RWP)120-5103 Verification of Dose Estimates and Exposure Tracking Systems (IP Section 03.02) (4 Samples)
The inspectors evaluated dose estimates and exposure tracking for the following work activities.
: (1) Repair/Replace Gasket on the Cavity NI Covers under Radiation Work Permit (RWP)120-5115
: (2) Insulation Work Activities in Containment under Radiation Work Permit (RWP)120-5016
: (3) Contractor Services Activities in Containment under Radiation Work Permit (RWP)120-5032
: (4) Under Vessel Inspections Following NI Covers under Radiation Work Permit (RWP)120-5103
 
==71124.03 - In-Plant Airborne Radioactivity Control and Mitigation==
 
===Permanent Ventilation Systems (IP Section 03.01) (1 Sample)===
The inspectors evaluated the configuration of the following permanently installed ventilation    systems:
: (1) Unit 1 Control 1 Control Room Emergency Ventilation System
 
===Use of Respiratory Protection Devices (IP Section 03.03) (1 Sample)===
: (1) The inspectors evaluated the licensees use of respiratory protection devices
 
===Self-Contained Breathing Apparatus for Emergency Use (IP Section 03.04) (1 Sample)===
: (1) The inspectors evaluated the licensees use and maintenance of self-contained            breathing apparatuses
 
==71124.05 - Radiation Monitoring Instrumentation==
 
===Walkdowns and Observations (IP Section 03.01) (10 Samples)===
The inspectors evaluated the following radiation detection instrumentation during plant walkdowns:
: (1) Frisker - Ludlum Model 12 2.7.625 ready for use
: (2) Extendable Survey Meter - Mirion Telepole 2.7.342 ready for use
: (3) Extendable Survey Meter - Mirion Telepole 2.7.343 ready for use
: (4) Portable Ion Chamber - Victoreen 451B 2.7.525 ready for use
: (5) Portable Ion Chamber - Victoreen 451B 2.7.535 ready for use
: (6) Portable Ion Chamber - Victoreen 451B 2.7.616 ready for use
: (7) Personnel Contamination Monitor - Mirion ARGOS-5AB 2.12.111 in auxiliary building
: (8) Personnel Contamination Monitor - Mirion ARGOS-5AB 2.12.96 at auxiliary building exit
: (9) Portal Monitor - Mirion GEM-5 2.12.116 at auxiliary building exit
: (10) Portable Air Monitor - Thermo Fisher AMS-4 2.8.171 in auxiliary building
 
==INSPECTION RESULTS==
Spent Fuel Storage Cask Design Changes Cornerstone        Severity                                        Cross-Cutting  Report Aspect          Section Not                Severity Level IV                              Not            60855 Applicable        NCV 05000346/2021002-01                        Applicable Open/Closed The inspectors identified a Severity Level IV Non-Cited Violation (NCV) of Title 10 of the Code of Federal Regulations (CFR) 72.48(d)(1), Changes, Tests, and Experiments, for failing to maintain a record of a change to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to 10 CFR 72.48(c)(2).
 
Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus potentially impact the analyzed fuel cladding temperatures, which consistent with NRC endorsed industry guidance, would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed.
 
Additionally, in the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the supporting adiabatic heat up calculation, which differed from the ANSYS Fluent models in the NUHOMS EOS Updated Final Safety Analysis Report (UFSAR), was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.
 
=====Description:=====
In October 2019, the licensee loaded the first Certificate of Compliance (CoC)1042, Amendment 0, NUHOMS EOS System. While processing their first EOS-37 dry shielded canister (DSC), DSC No. 9, the licensee experienced unexpected issues complicating the drying process. Specifically, the licensee was unable to demonstrate the dryness criterion was met during vacuum drying as specified in the NUHOMS EOS Technical Specification (TS) limiting condition of operation (LCO) 3.1.1. LCO 3.1.1 states, in part, that The DSC vacuum drying pressure shall be sustained at or below 3 Torr (3 mm Hg)absolute for a period of at least 30 minutes following evacuation. While troubleshooting the issue, the licensee backfilled the canister with helium so that the fittings could be checked for leakage. When the licensee backfilled the canister with helium, the water in the annulus began to rapidly boil. The boiling in the annulus created a safety hazard to personnel, so the licensee backed out of the procedure by drawing a vacuum. The licensee worked with the CoC holder and eventually identified and fixed a leaking fitting that was preventing them from meeting the dryness criteria. The licensee then completed processing the canister and was able to meet TS requirements.
 
Given the extended time in vacuum drying and the changing thermal environment in the DSC during troubleshooting, the inspectors questioned whether the canister conditions encountered during troubleshooting were consistent with the design basis thermal analysis described in Chapter 4 of the NUHOMS EOS UFSAR, Revision 1. Once the licensee completed processing the canister, the licensee consulted with the CoC holder to address the issues experienced during the vacuum drying process. The licensee made several changes to the UFSAR using the 10 CFR 72.48 process. To complete a review of the thermal analysis and the changes made to the UFSAR, the inspectors opened Unresolved Item (URI)05000346/2019004-01 (ML20035D918).
 
The NRC staff reviewed the licensees corrective actions associated with the conditions encountered during troubleshooting. This included a review of calculations concluding that temperatures did not exceed the maximum peak cladding temperature limits specified in the UFSAR. Also reviewed were changes to the UFSAR made following the issues encountered during vacuum drying of DSC No. 9. The NRC staff identified the following issues associated with the licensees UFSAR changes:
1) Section 4.5.11 of the EOS UFSAR states the water in the annulus is monitored and replenished with fresh water to prevent boiling, and to maintain the water level if excessive evaporation occurs Presence of water within the annulus maintains the maximum DSC shell temperature below the boiling temperature of water in open atmosphere (223°F). Title 10 CFR 72.48 screening No. 721042-146, dated October 18, 2019, revised these statements in the UFSAR. Specifically, the licensee changed the language in the UFSAR from no boiling of water in the annulus to an expectation of boiling at high heat loads. The change also provided additional instructions that the annulus must remain open to the atmosphere and how to add water to the annulus to ensure water level is maintained.
 
In the screening, the licensee stated that the changes being made were editorial in nature and provided additional clarification. However, UFSAR Section 4.5.11 was consistent with the NRCs Safety Evaluation Report for this system which stated that the water in the annulus would be maintained below the boiling temperature of water to ensure the canister shell would be maintained below 223°F at a given pressure. These assumptions can only be met with a constant pressure in the DSC and subcooled water in the annulus so that the evaluation performed remained valid. Hence, boiling in the annulus would have an adverse effect on the design function conditions that maintain the DSC shell below 223°F during vacuum drying operations and subsequently the design function to keep peak cladding (a fission product barrier) temperatures within limits. Therefore, the licensee incorrectly concluded in their screening that there were no changes involving a system, structure, or component that adversely affected a design function described in the UFSAR. Furthermore, the licensee failed to recognize that changes to thermal conditions in the annulus and DSC shell temperatures potentially impact the analyzed fuel cladding temperatures. Potential changes to fuel cladding impacts, adverse or not, should be evaluated per 72.48 as noted in industry guidance endorsed by the NRC in Regulatory Guide 3.72, Guidance for Implementation of 10 CFR 72.48, Changes, Tests, and Experiments, Revision 0. These evaluations are required to provide the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2).
 
2) In 10 CFR 72.48 evaluation No. 721042-155, dated October 29, 2019, the licensee evaluated a change to the UFSAR establishing additional limits for a canister in vacuum drying. Specifically, the change modified steps 17 and 24 in Section 9.1.3 of the UFSAR limiting the canister to a pressure below 3 Torr for 3 hours before pressure must then be raised. This change was supported by calculation No. 503948-0404, Revision 0, that evaluated the thermal impact of the proposed UFSAR changes establishing additional vacuum drying operation limitations.
 
Section 4.4, Thermal Evaluation for Storage, of the EOS UFSAR states ANSYS Fluent CFD [Computational Fluid Dynamics] models are used to demonstrate that the maximum temperatures of key components such as fuel cladding, concrete, heat shields, etc. are below maximum temperature limits. Section 4.5.2.2 of the EOS UFSAR states similar to the modeling approach used for evaluation of storage conditions, the unstructured meshes for the EOS-37PTH DSC basket assembly and the EOS-TC125 are imported and combined into ANSYS Fluent to create an integrated model. Finally, Section 4.5.11 states the EOS-37 DSC models described in Section 4.5.2 are used to determine the maximum fuel cladding temperatures for vacuum drying operations. In 72.48 evaluation No. 721042-155, the licensee concluded that calculation No. 503948-0404, Revision 0, follows the same methodology as described in Section 4.5 of the UFSAR. Therefore, this change does not depart from a method of evaluation described in the UFSAR. As noted above, the UFSAR establishes that ANSYS Fluent models are used to demonstrate key components are below maximum temperature limits. However, calculation No. 503948-0404, Revision 0, used the maximum fuel cladding temperature calculated in the UFSAR and assumed an adiabatic heat up for the time duration being evaluated. The heat up rate chosen was taken from UFSAR Section 4.4.8. This section provides a method for comparing EOS 37 DSC heat up rates to the EOS 89 DSC, but it does not provide a method to demonstrate that the maximum temperatures of key components such as fuel cladding are below maximum temperature limits as stated in Section 4.4 of the EOS UFSAR. In the 72.48 evaluation, the licensee failed to demonstrate that the adiabatic heat up calculation, which differed from the ANSYS Fluent models in the EOS UFSAR, was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii).
 
Corrective Actions: The concern was placed in the corrective action program. Following initial loading of DSC No. 9, calculations were performed by the licensee, and independently reviewed by the NRC, which concluded that temperatures did not exceed the maximum peak cladding temperature limits specified in the UFSAR. Therefore, there was no immediate safety concern. Additional corrective actions are still in progress and include evaluating the need for additional changes to restore compliance as well as performing a causal evaluation regarding the circumstances of the non-compliance.
 
Corrective Action References: CR-2021-05199; Potential NCV of 10 CFR 72.48 for 2019 DB Fuel Loading Campaign; July 8, 2021
 
=====Performance Assessment:=====
None Screening: The inspectors determined that the violation was of more than minor significance using NRC Enforcement Manual, Appendix E, "Example of Minor Issues." Specifically, the example for Minor changes to requirements was found to be similar and resulted in a more than minor determination since there was reasonable likelihood that the change would require prior NRC approval.
 
Significance: In accordance with Section 2.2 of the Enforcement Policy, ISFSIs are not subject to the Significance Determination Process (SDP) and traditional enforcement will be used for these facilities. Traditional enforcement violations are not assessed for cross-cutting aspects.
 
=====Enforcement:=====
Severity: The inspectors determined that the violation could be evaluated using Section 6.1.d.2 of the NRC Enforcement Policy as a Severity Level IV violation because, although more than minor, the resultant condition was of very low safety significance because the changes did not result in temperatures in the canister exceeding regulatory limits.
 
Violation: Title 10 CFR 72.48(d)(1) requires, in part, the licensee to maintain records of changes in the facility or spent fuel storage cask design, of changes in procedures, and of tests and experiments made pursuant 10 CFR 72.48(c). These records must include a written evaluation which provides the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to paragraph (c)(2) of this section.
 
Title 10 CFR 72.48(c)(2)(viii) requires, in part, that a specific licensee obtain a license amendment pursuant to 10 CFR 72.56 prior to implementing a proposed change if the change would result in a departure from a method of evaluation described in the FSAR (as updated) used in establishing the safety analyses performed.
 
Title 10 CFR 72.48(a)(2)(ii) states, in part, that definitions for the purposes of this section include departure from a method of evaluation described in the FSAR (as updated) used in establishing the design bases means changing from a method described in the FSAR to another method unless that method has been approved by NRC for the intended application.
 
UFSAR Section 4.4, Thermal Evaluation for Storage, of the EOS UFSAR states, in part, ANSYS Fluent CFD [Computational Fluid Dynamics] models are used to demonstrate that the maximum temperatures of key components such as fuel cladding, concrete, heat shields, etc. are below maximum temperature limits.
 
UFSAR Section 4.5.11 states the EOS-37 DSC models described in Section 4.5.2 are used to determine the maximum fuel cladding temperatures for vacuum drying operations.
 
Section 4.5.11 also states the water in the annulus is monitored and replenished with fresh water to prevent boiling. The presence of water within the annulus maintains the maximum DSC shell temperature below the boiling temperature of water in open atmosphere (223°F).
 
Contrary to the above, on October 18 and October 29, 2019, the licensee failed to maintain a record of two changes to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change did not require a license amendment pursuant to 10 CFR 72.48(c)(2). Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus and DSC shell temperatures potentially impact the analyzed fuel cladding temperatures, which would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed. In the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the adiabatic heat up calculation, which differed from the ANSYS Fluent models in the EOS UFSAR described above, was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.
 
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
 
The disposition of this violation closes URI: 05000346/2019004-01.
 
URI                  Unresolved Item Regarding Peak Fuel Clad Temperature          60855 During Vacuum Drying of Canister #9 URI 05000346/2019004-01
 
=====Description:=====
This URI is being closed to a Severity Level IV NCV in this report.
Corrective Action Reference(s): CR-2019-09156
 
==EXIT MEETINGS AND DEBRIEFS==
The inspectors verified no proprietary information was retained or documented in this report.
 
On July 27, 2021, the inspectors presented the integrated inspection results to Mr. T. Brown, Site Vice President, and other members of the licensee staff.
 
On May 14, 2021, the inspectors presented the radiation protection inspection results to Mr. D. Huey, General Plant Manager, and other members of the licensee staff.
 
=DOCUMENTS REVIEWED=
 
Inspection Type              Designation      Description or Title                                  Revision or
Procedure                                                                                            Date
60855      Calculations      Calc No. 503948- Thermal Evaluation of EOS-37PTH in EOS-TC125 During    1
0405            the Vacuum Drying Process for the 2019 Davis Besse Dry
Cask Loading Storage Campaign
Miscellaneous    10 CFR Screening TN Americas 10 CFR Part 72. 48 Applicability Review    0
No. 721042-146  Regarding Water Boiling in the TC/DSC Annulus
CFR Screening TN Americas 10 CFR Part 72. 48 Applicability Review    0
No. 721042-155  Regarding Time Limit in Low Vacuum Pressure
71111.01  Corrective Action CR-2021-04332    Environmental Conditions Necessitate Entering RA-EP-  05/30/2021
Documents                          02830 Flooding Off-Normal Procedure
Procedures        RA-EP-02830      Emergency Plan Off-Normal Occurrence Procedure        06
71111.04  Corrective Action CR-2018-06716    EDG 1 SYNC Selector Switch does not Positively Lock    07/27/2018
Documents                          onto the DG BKR TO C1 Position
CR-2021-04913    EDG 1 Overvoltage during Monthly Run (EDG 1            0
Unavailable)
Procedures        DB-OP-06316      Diesel Generator Operating Procedure                  65
DB-OP-06334      Station Blackout Diesel - Diesel Generator Operating  32
Procedure
71111.05  Calculations      F-FP-013.10-014  Fire Compartment BG-01, Service Water Pipe Tunnel and  02
Valve Rooms
Corrective Action CR-2019-08665    Aux Feed Pump Sliding Door 363 Safety Concern          11/19/2019
Documents        CR-2021-04075    Fire Protection Identified Issue of Combustible Floor  05/19/2021
Covering Under Door 510
CR-2021-04868    Door 215 Interlock Mechanism Degraded                  06/22/2021
Fire Plans        PFP-AB-238      Protected Area Pre-Fire Plan, Auxiliary Feed Pump 2    05
Room - Room 238 Fire Area F
PFP-AB-505      Control Room and Adjacent Support Rooms Fire Area FF  09
PFP-IS-52        Service Water Pump Room 52                            04
PFP-TB-250      Protected Area Pre-Fire Plan Service Water Pipe Tunnel 05
Room 250
Miscellaneous    FHAR            Hazard Analysis Report                                30
71111.12  Corrective Action 2019-03616      Perform Performance GAP Analysis to Determine if there 04/18/2019
Documents                          is a GAP in Skills and Knowledge Regarding EDG PM
Inspection Type              Designation  Description or Title                                    Revision or
Procedure                                                                                          Date
Scope
20-01501    Unexpected SBODG Trip during Electronic Governor        02/27/2020
Adjustment
20-01540    SBODG Fuse 2 (DC Fuel Pump) Blew during Testing          02/28/2020
21-04913    EDG 1 Overvoltage during Monthly Run                    06/24/2021
21-0582    SBODG Voltage Regulator 1 Green Light Flashing          06/10/2021
221-04601  SBODG Voltage Regulators 1 and 2 Malfunctions            06/11/2021
CR-2021-04582 SBODG Voltage Regulator 1 Green Light Flashing          06/10/2021
Drawings          0200-0078-02  EDG Excitation System Interconnection Diagram            7
Miscellaneous    0200-0078-04  EDG Excitation System RA-70 Configurable Settings        0
MPR-2838      Evaluation of Reliability of Replacement EDG Excitation  1
System for Davis-Besse Nuclear Power Plant [Proprietary]
Trend        Single Point Trend                                      06/24/2021
Procedures        DB-MM-09320  Emergency and Station Blackout Diesel Engine            50
Maintenance
Work Orders      200789507    SBODG Monthly Test                                      0
200789645    SBODG Overspeed Trip Test                                0
200810209    SBODG License Renewal Inspection                        0
200817105    PM 7257 Replace Adjuster RA-70 EDG 1                    06/25/2021
200857743    Troubleshoot Voltage Regulator Due to Failure            06/24/2021
601323347    Replace Voltage Regulator EDG 1                          06/24/2021
71111.13  Corrective Action CR-2021-04310 Containment Entry Dose Rates were Higher than            05/28/2021
Documents                      Expected
CR-2021-04332 Environmental Conditions Necessitate Entering RA-EP-    05/30/2021
2830 Flooding Off-Normal Procedure
Procedures        DB-OP-03013  Surveillance Test Procedure, Containment Daily          11
Inspection and Containment Closeout Inspection
NOP-OP-1007  Risk Management                                          34
RA-EP-02830  Emergency Plan Off-Normal Occurrence Procedure          06
71111.15  Corrective Action 2002-02203    Emergency Diesel Generator 1 Emergency Shutdown          03/13/2020
Documents        2020-02222    Diode for Relay K2 Shorted                              03/14/2020
20-05188    Missed Opportunity during MRB Review of CR 2020-        06/22/2020
203
Inspection Type          Designation        Description or Title                                    Revision or
Procedure                                                                                          Date
21-04282        EDG 1 Failed to Reach Required Voltage and Frequency    05/27/2021
during the 184 Day Test
CR-2021-04909      EDG 1 RICE Rule Violation                              06/24/2021
Drawings      0200-0078-02      EDG Excitation System Interconnection Diagram          7
B15702501          Schematic Diagram Engine Control for Emergency Diesel  T21
Generator 1 - 1
E559-SH 4          Emergency Diesel Generator 1 - 1 Engine Control Panel  20
Engineering  NOP-CC-2003-05    ECR 03-0080-00, Replace EDG 1 - 1 Field Flash          06/18/2003
Changes                          Contactor (FFC)
NOP-CC-2003-16    On DCNs M-180-47-0010 and M-180-48-000 Change the      07/08/2003
Destination of the 'N' Conductor from FCC to FFC
Engineering  EER-14-94013-02    SBM Selector Switches                                  0
Evaluations
Miscellaneous COLR              Core Operating Limits Report                            22
GE Manual          SBM Switch Overview                                    0
GET-6169G          Selection and Application Guide for SB Control and      0
Transfer Switches
Instruction Manual SB Control and Transfer Switches - GE Power
Management
Letter to NRC from Report No: P21-01072015 Report of Potential Failure of  01/08/2015
AZZ Nuclear        GE Hitachi (GEH) SBM Type Switches per 10CFR Part 21
Letter to NRC from 10CFR21 Interim Letter, UCI Not Capable to Determine if 04/08/2014
United Controls    Defect Exist General Electric SB1 Switches and HEA
International      Relays
71111.18  Work Orders  200772884          Install Constant Level Oilers on DHP-1                  0
71111.19  Procedures    DB-PF-03291        Surveillance Test Procedure, Containment Personal and  14
Emergency Airlock Seal Leakage Test
DB-SC-03070        Emergency Diesel Generator 1 Monthly Test              42
DB-SC-03070        Emergency Diesel Generator 1 Monthly Test              43
Work Orders  200856554          PF3291 Personnel Air Lock                              0
71111.22  Procedures    DB-MI-03205        Surveillance Test Procedure, Channel Functional        27
Test/Calibration and Response Time of RCP Monitor
                                            (RC3601) to SFRCS LCH 1 and RPS Channel 1
71124.02  ALARA Plans  120-5016          Insulation Work Activities in Containment              Various
Inspection Type              Designation    Description or Title                                  Revision or
Procedure                                                                                        Date
20-5032      Contractor Services Activities in Containment        Various
20-5103      Under Vessel Inspections Following NI Covers          Various
20-5115      Repair/Replace Gasket on the Cavity NI Covers        Various
Miscellaneous                    Davis-Besse 1R21 Outage ALARA Report                  1
Radiation Work    120-5016      Insulation Work Activities in Containment            Various
Permits (RWPs)    120-5032      Contractor Services Activities in Containment        Various
20-5103      Under Vessel Inspections Following NI Covers          Various
20-5115      Repair/Replace Gasket on the Cavity NI Covers        Various
71124.03  Calculations      NOP-OP-4107-15 ALARA DAC Evaluation - Under Vessel Inspection        03/14/2020
RWP#120-5103
NOP-OP-4107-15 ALARA DAC Evaluation - Insulation Work Activities in  02/09/2020
RWP#120-6016  Containment
Corrective Action CR-2019-06640  Calculated DAC Dose Fractions Were Exceeded by more  08/09/2019
Documents                        than +/- 10% during DB-HP-04344
Corrective Action CR-2021-03462  Rust Identified on Self-Contained Breathing Apparatus 04/27/2021
Documents
Resulting from
Inspection
Miscellaneous                    Ventilation Filter Testing Program                    3
GEN-M7SCBA_FEN FireHawk M7 SCBA Training                            4
GEN-          Industrial Safety - Respiratory Protection Training  1
PAPRHOODTL_FEN
GEN-          Full-Face Respirator Practical Exercise              2
RESPPRAC_REN-
MMR 2nd Stage  MSA Regulator Service Report - Annual Flow Test      01/11/2020
Regulator
AMAA277770
MMR 2nd Stage  MSA Regulator Service Report - Annual Flow Test      08/26/2019
Regulator
AMAA277770
MMR 2nd Stage  MSA Regulator Service Report - Annual Flow Test      08/26/2019
Regulator
AOAA257126
Inspection Type        Designation  Description or Title                                  Revision or
Procedure                                                                                  Date
MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test        08/11/2020
Regulator
AOAA257126
MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test        08/27/2019
Regulator
AOAA330144
MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test        08/11/2020
Regulator
AOAA330144
Procedures  NOP-ER-3202  Control Room Envelope Habitability (CREHAB) Program    00
RP-AA-106    Respiratory Protection Program                        4
Work Orders DB-SS3146-001 CREVS Train 2 Filter Test                              01/30/2019
DB-SS3302-001 CREVS Tracer Gas Test Train 2                          05/17/2018
71124.05  Procedures  DB-HP-00010  Radiation Measuring and Test Equipment Calibration and 12
Control Program
16
}}
}}

Revision as of 00:57, 9 September 2021

Integrated Inspection Report 05000346/2021002 and 07200014/2021001
ML21224A237
Person / Time
Site: Davis Besse  Cleveland Electric icon.png
Issue date: 08/12/2021
From: Billy Dickson
NRC/RGN-III/DRP/B2
To: Tony Brown
Energy Harbor Nuclear Corp
References
IR 2021001
Download: ML21224A237 (19)


Text

August 12, 2021

SUBJECT:

DAVIS-BESSE NUCLEAR POWER STATION - INTEGRATED INSPECTION REPORT 05000346/2021002 AND 07200014/2021001

Dear Mr. Brown:

On June 30, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Davis-Besse Nuclear Power Station. On July 27, 2021, the NRC inspectors discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.

One Severity Level IV violation without an associated finding is documented in this report. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.

No NRC-identified or self-revealing findings were identified during this inspection.

If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:

Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; the Director, Office of Enforcement; and the NRC Resident Inspector at Davis-Besse Nuclear Power Station. 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 Dickson, Billy on 08/12/21 Billy C. Dickson, Jr., Chief Branch 2 Division of Reactor Projects Docket No. 05000346; 07200014 License No. NPF-3

Enclosure:

As stated

Inspection Report

Docket Number: 05000346; 07200014 License Number: NPF-3 Report Number: 05000346/2021002 AND 07200014/2021001 Enterprise Identifier: I-2021-002-0078 Licensee: Energy Harbor Nuclear Corp.

Facility: Davis-Besse Nuclear Power Station Location: Oak Harbor, OH Inspection Dates: April 01, 2021 to June 30, 2021 Inspectors: R. Cassara, Resident Inspector J. Cassidy, Senior Health Physicist J. Dalzell, Project Engineer R. Edwards, Senior Health Physicist D. Mills, Senior Resident Inspector R. Ruiz, Project Engineer Approved By: Billy C. Dickson, Jr., Chief Branch 2 Division of Reactor Projects Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Davis-Besse Nuclear Power Station, 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

Spent Fuel Storage Cask Design Changes Cornerstone Severity Cross-Cutting Report Aspect Section Not Applicable Severity Level IV Not Applicable 60855 NCV 05000346/2021002-01 Open/Closed The inspectors identified a Severity Level IV Non-Cited Violation (NCV) of Title 10 of the Code of Federal Regulations (CFR) 72.48(d)(1), Changes, Tests, and Experiments, for failing to maintain a record of a change to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to 10 CFR 72.48(c)(2). Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus potentially impact the analyzed fuel cladding temperatures, which consistent with NRC endorsed industry guidance, would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed. Additionally, in the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the supporting adiabatic heat up calculation, which differed from the ANSYS Fluent models in the NUHOMS EOS Updated Final Safety Analysis Report (UFSAR), was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.

Additional Tracking Items

Type Issue Number Title Report Section Status URI 05000346/2019004-01 Unresolved Item Regarding 60855 Closed Peak Fuel Clad Temperature During Vacuum Drying of Canister 9

PLANT STATUS

Unit 1 began the inspection period at rated thermal power. On May 21, 2021, the unit was down powered to 40 percent to perform scheduled testing of the turbine stop valves. The unit was returned to rated thermal power on May 22, 2021 and remained at or near rated thermal power 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

Impending Severe Weather Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from high lake levels and localized flooding in the area surrounding the plant due to heavy rain and high winds during the week ending June 1, 2021.

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (2 Samples)

The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:

(1) Emergency diesel generator train 1 during the week ending May 22, 2021
(2) Station blackout diesel generator during the week ending June 26, 2021

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (4 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) Control room and adjacent support rooms, fire area FF during the week ending May 22, 2021
(2) Service water pipe tunnel, fire area BG during the week ending June 12, 2021
(3) Auxiliary feed pump 2 room, fire area F during the week ending June 26, 2021
(4) Service water pump area and diesel fire pump area, rooms 51 and 52, fire area BF during the week ending June 26, 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 (SSCs) remain capable of performing their intended function:

(1) PT-RCA1 reactor coolant system pressure transmitter replacement during the week ending May 29, 2021
(2) Station blackout diesel generator license renewal maintenance during the week ending June 12, 2021

Quality Control (IP Section 03.02) (1 Sample)

The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:

(1) Emergency diesel generator 1 voltage regulator reference adjuster replacement during the week ending June 26, 2021

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (5 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) Elevated risk due to downpower to 40 percent for turbine stop valve testing during the week ending May 22, 2021
(2) Elevated risk during emergent work in containment to replace PT-RC2A1 reactor coolant system pressure transmitter during the week ending May 29, 2021
(3) Elevated risk while emergency diesel generator 1 inoperable due to failed field flash switch during the week ending May 29, 2021
(4) Elevated risk during period of high winds and rain causing local flooding during the week ending May 29, 2021
(5) Elevated risk due to the failure of emergency diesel generator 1 voltage regulator reference adjuster during the week ending June 26, 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) Component cooling water train 2 ventilation damper malfunction, CR 2021-04374
(2) Cycle 22 1/8 core location H14 max-segment peaking deviation approaching BMAC limit, CR 2021-04524
(3) EDG 1 failed to reach required voltage and frequency during the 184-day test, CR 2021-04282
(4) EDG 1 overvoltage during monthly run, CR 2021-04913

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)

(1 Sample)

The inspectors evaluated the following temporary or permanent modifications:

(1) Installation of constant level oilers on decay heat pump 1 during the week ending May 29, 2021

71111.19 - Post-Maintenance Testing

Post-Maintenance Test Sample (IP Section 03.01) (3 Samples)

The inspectors evaluated the following post-maintenance test activities to verify system operability and functionality:

(1) Emergency diesel generator train 1 following replacement of field flash selector switch during the week ending May 29, 2021
(2) Emergency diesel generator train 1 following replacement of voltage regulator reference adjuster during the week ending July 3, 2021
(3) Personnel hatch local leak rate testing following containment entry during the week ending May 29, 2021

71111.22 - Surveillance Testing

The inspectors evaluated the following surveillance tests:

Surveillance Tests (other) (IP Section 03.01)

(1) Emergency diesel generator 2 testing during the week ending June 5, 2021
(2) Channel functional test of reactor coolant pump monitor to steam feed rupture control system channel 1 and reactor protection system channel 1 during the week ending June 19,

RADIATION SAFETY

71124.02 - Occupational ALARA Planning and Controls

Radiological Work Planning (IP Section 03.01) (4 Samples)

The inspectors evaluated the licensees radiological work planning for the following work activities.

(1) Repair/Replace Gasket on the Cavity Nuclear Instrumentation (NI) Covers under Radiation Work Permit (RWP) 120-5115
(2) Insulation Work Activities in Containment under Radiation Work Permit (RWP)120-5016
(3) Contractor Services Activities in Containment under Radiation Work Permit (RWP)120-5032
(4) Under Vessel Inspections Following NI Covers under Radiation Work Permit (RWP)120-5103 Verification of Dose Estimates and Exposure Tracking Systems (IP Section 03.02) (4 Samples)

The inspectors evaluated dose estimates and exposure tracking for the following work activities.

(1) Repair/Replace Gasket on the Cavity NI Covers under Radiation Work Permit (RWP)120-5115
(2) Insulation Work Activities in Containment under Radiation Work Permit (RWP)120-5016
(3) Contractor Services Activities in Containment under Radiation Work Permit (RWP)120-5032
(4) Under Vessel Inspections Following NI Covers under Radiation Work Permit (RWP)120-5103

71124.03 - In-Plant Airborne Radioactivity Control and Mitigation

Permanent Ventilation Systems (IP Section 03.01) (1 Sample)

The inspectors evaluated the configuration of the following permanently installed ventilation systems:

(1) Unit 1 Control 1 Control Room Emergency Ventilation System

Use of Respiratory Protection Devices (IP Section 03.03) (1 Sample)

(1) The inspectors evaluated the licensees use of respiratory protection devices

Self-Contained Breathing Apparatus for Emergency Use (IP Section 03.04) (1 Sample)

(1) The inspectors evaluated the licensees use and maintenance of self-contained breathing apparatuses

71124.05 - Radiation Monitoring Instrumentation

Walkdowns and Observations (IP Section 03.01) (10 Samples)

The inspectors evaluated the following radiation detection instrumentation during plant walkdowns:

(1) Frisker - Ludlum Model 12 2.7.625 ready for use
(2) Extendable Survey Meter - Mirion Telepole 2.7.342 ready for use
(3) Extendable Survey Meter - Mirion Telepole 2.7.343 ready for use
(4) Portable Ion Chamber - Victoreen 451B 2.7.525 ready for use
(5) Portable Ion Chamber - Victoreen 451B 2.7.535 ready for use
(6) Portable Ion Chamber - Victoreen 451B 2.7.616 ready for use
(7) Personnel Contamination Monitor - Mirion ARGOS-5AB 2.12.111 in auxiliary building
(8) Personnel Contamination Monitor - Mirion ARGOS-5AB 2.12.96 at auxiliary building exit
(9) Portal Monitor - Mirion GEM-5 2.12.116 at auxiliary building exit
(10) Portable Air Monitor - Thermo Fisher AMS-4 2.8.171 in auxiliary building

INSPECTION RESULTS

Spent Fuel Storage Cask Design Changes Cornerstone Severity Cross-Cutting Report Aspect Section Not Severity Level IV Not 60855 Applicable NCV 05000346/2021002-01 Applicable Open/Closed The inspectors identified a Severity Level IV Non-Cited Violation (NCV) of Title 10 of the Code of Federal Regulations (CFR) 72.48(d)(1), Changes, Tests, and Experiments, for failing to maintain a record of a change to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to 10 CFR 72.48(c)(2).

Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus potentially impact the analyzed fuel cladding temperatures, which consistent with NRC endorsed industry guidance, would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed.

Additionally, in the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the supporting adiabatic heat up calculation, which differed from the ANSYS Fluent models in the NUHOMS EOS Updated Final Safety Analysis Report (UFSAR), was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.

Description:

In October 2019, the licensee loaded the first Certificate of Compliance (CoC)1042, Amendment 0, NUHOMS EOS System. While processing their first EOS-37 dry shielded canister (DSC), DSC No. 9, the licensee experienced unexpected issues complicating the drying process. Specifically, the licensee was unable to demonstrate the dryness criterion was met during vacuum drying as specified in the NUHOMS EOS Technical Specification (TS) limiting condition of operation (LCO) 3.1.1. LCO 3.1.1 states, in part, that The DSC vacuum drying pressure shall be sustained at or below 3 Torr (3 mm Hg)absolute for a period of at least 30 minutes following evacuation. While troubleshooting the issue, the licensee backfilled the canister with helium so that the fittings could be checked for leakage. When the licensee backfilled the canister with helium, the water in the annulus began to rapidly boil. The boiling in the annulus created a safety hazard to personnel, so the licensee backed out of the procedure by drawing a vacuum. The licensee worked with the CoC holder and eventually identified and fixed a leaking fitting that was preventing them from meeting the dryness criteria. The licensee then completed processing the canister and was able to meet TS requirements.

Given the extended time in vacuum drying and the changing thermal environment in the DSC during troubleshooting, the inspectors questioned whether the canister conditions encountered during troubleshooting were consistent with the design basis thermal analysis described in Chapter 4 of the NUHOMS EOS UFSAR, Revision 1. Once the licensee completed processing the canister, the licensee consulted with the CoC holder to address the issues experienced during the vacuum drying process. The licensee made several changes to the UFSAR using the 10 CFR 72.48 process. To complete a review of the thermal analysis and the changes made to the UFSAR, the inspectors opened Unresolved Item (URI)05000346/2019004-01 (ML20035D918).

The NRC staff reviewed the licensees corrective actions associated with the conditions encountered during troubleshooting. This included a review of calculations concluding that temperatures did not exceed the maximum peak cladding temperature limits specified in the UFSAR. Also reviewed were changes to the UFSAR made following the issues encountered during vacuum drying of DSC No. 9. The NRC staff identified the following issues associated with the licensees UFSAR changes:

1) Section 4.5.11 of the EOS UFSAR states the water in the annulus is monitored and replenished with fresh water to prevent boiling, and to maintain the water level if excessive evaporation occurs Presence of water within the annulus maintains the maximum DSC shell temperature below the boiling temperature of water in open atmosphere (223°F). Title 10 CFR 72.48 screening No. 721042-146, dated October 18, 2019, revised these statements in the UFSAR. Specifically, the licensee changed the language in the UFSAR from no boiling of water in the annulus to an expectation of boiling at high heat loads. The change also provided additional instructions that the annulus must remain open to the atmosphere and how to add water to the annulus to ensure water level is maintained.

In the screening, the licensee stated that the changes being made were editorial in nature and provided additional clarification. However, UFSAR Section 4.5.11 was consistent with the NRCs Safety Evaluation Report for this system which stated that the water in the annulus would be maintained below the boiling temperature of water to ensure the canister shell would be maintained below 223°F at a given pressure. These assumptions can only be met with a constant pressure in the DSC and subcooled water in the annulus so that the evaluation performed remained valid. Hence, boiling in the annulus would have an adverse effect on the design function conditions that maintain the DSC shell below 223°F during vacuum drying operations and subsequently the design function to keep peak cladding (a fission product barrier) temperatures within limits. Therefore, the licensee incorrectly concluded in their screening that there were no changes involving a system, structure, or component that adversely affected a design function described in the UFSAR. Furthermore, the licensee failed to recognize that changes to thermal conditions in the annulus and DSC shell temperatures potentially impact the analyzed fuel cladding temperatures. Potential changes to fuel cladding impacts, adverse or not, should be evaluated per 72.48 as noted in industry guidance endorsed by the NRC in Regulatory Guide 3.72, Guidance for Implementation of 10 CFR 72.48, Changes, Tests, and Experiments, Revision 0. These evaluations are required to provide the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2).

2) In 10 CFR 72.48 evaluation No. 721042-155, dated October 29, 2019, the licensee evaluated a change to the UFSAR establishing additional limits for a canister in vacuum drying. Specifically, the change modified steps 17 and 24 in Section 9.1.3 of the UFSAR limiting the canister to a pressure below 3 Torr for 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> before pressure must then be raised. This change was supported by calculation No. 503948-0404, Revision 0, that evaluated the thermal impact of the proposed UFSAR changes establishing additional vacuum drying operation limitations.

Section 4.4, Thermal Evaluation for Storage, of the EOS UFSAR states ANSYS Fluent CFD [Computational Fluid Dynamics] models are used to demonstrate that the maximum temperatures of key components such as fuel cladding, concrete, heat shields, etc. are below maximum temperature limits. Section 4.5.2.2 of the EOS UFSAR states similar to the modeling approach used for evaluation of storage conditions, the unstructured meshes for the EOS-37PTH DSC basket assembly and the EOS-TC125 are imported and combined into ANSYS Fluent to create an integrated model. Finally, Section 4.5.11 states the EOS-37 DSC models described in Section 4.5.2 are used to determine the maximum fuel cladding temperatures for vacuum drying operations. In 72.48 evaluation No. 721042-155, the licensee concluded that calculation No. 503948-0404, Revision 0, follows the same methodology as described in Section 4.5 of the UFSAR. Therefore, this change does not depart from a method of evaluation described in the UFSAR. As noted above, the UFSAR establishes that ANSYS Fluent models are used to demonstrate key components are below maximum temperature limits. However, calculation No. 503948-0404, Revision 0, used the maximum fuel cladding temperature calculated in the UFSAR and assumed an adiabatic heat up for the time duration being evaluated. The heat up rate chosen was taken from UFSAR Section 4.4.8. This section provides a method for comparing EOS 37 DSC heat up rates to the EOS 89 DSC, but it does not provide a method to demonstrate that the maximum temperatures of key components such as fuel cladding are below maximum temperature limits as stated in Section 4.4 of the EOS UFSAR. In the 72.48 evaluation, the licensee failed to demonstrate that the adiabatic heat up calculation, which differed from the ANSYS Fluent models in the EOS UFSAR, was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii).

Corrective Actions: The concern was placed in the corrective action program. Following initial loading of DSC No. 9, calculations were performed by the licensee, and independently reviewed by the NRC, which concluded that temperatures did not exceed the maximum peak cladding temperature limits specified in the UFSAR. Therefore, there was no immediate safety concern. Additional corrective actions are still in progress and include evaluating the need for additional changes to restore compliance as well as performing a causal evaluation regarding the circumstances of the non-compliance.

Corrective Action References: CR-2021-05199; Potential NCV of 10 CFR 72.48 for 2019 DB Fuel Loading Campaign; July 8, 2021

Performance Assessment:

None Screening: The inspectors determined that the violation was of more than minor significance using NRC Enforcement Manual, Appendix E, "Example of Minor Issues." Specifically, the example for Minor changes to requirements was found to be similar and resulted in a more than minor determination since there was reasonable likelihood that the change would require prior NRC approval.

Significance: In accordance with Section 2.2 of the Enforcement Policy, ISFSIs are not subject to the Significance Determination Process (SDP) and traditional enforcement will be used for these facilities. Traditional enforcement violations are not assessed for cross-cutting aspects.

Enforcement:

Severity: The inspectors determined that the violation could be evaluated using Section 6.1.d.2 of the NRC Enforcement Policy as a Severity Level IV violation because, although more than minor, the resultant condition was of very low safety significance because the changes did not result in temperatures in the canister exceeding regulatory limits.

Violation: Title 10 CFR 72.48(d)(1) requires, in part, the licensee to maintain records of changes in the facility or spent fuel storage cask design, of changes in procedures, and of tests and experiments made pursuant 10 CFR 72.48(c). These records must include a written evaluation which provides the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to paragraph (c)(2) of this section.

Title 10 CFR 72.48(c)(2)(viii) requires, in part, that a specific licensee obtain a license amendment pursuant to 10 CFR 72.56 prior to implementing a proposed change if the change would result in a departure from a method of evaluation described in the FSAR (as updated) used in establishing the safety analyses performed.

Title 10 CFR 72.48(a)(2)(ii) states, in part, that definitions for the purposes of this section include departure from a method of evaluation described in the FSAR (as updated) used in establishing the design bases means changing from a method described in the FSAR to another method unless that method has been approved by NRC for the intended application.

UFSAR Section 4.4, Thermal Evaluation for Storage, of the EOS UFSAR states, in part, ANSYS Fluent CFD [Computational Fluid Dynamics] models are used to demonstrate that the maximum temperatures of key components such as fuel cladding, concrete, heat shields, etc. are below maximum temperature limits.

UFSAR Section 4.5.11 states the EOS-37 DSC models described in Section 4.5.2 are used to determine the maximum fuel cladding temperatures for vacuum drying operations.

Section 4.5.11 also states the water in the annulus is monitored and replenished with fresh water to prevent boiling. The presence of water within the annulus maintains the maximum DSC shell temperature below the boiling temperature of water in open atmosphere (223°F).

Contrary to the above, on October 18 and October 29, 2019, the licensee failed to maintain a record of two changes to the spent fuel storage cask design that includes a written evaluation providing the bases for the determination that the change did not require a license amendment pursuant to 10 CFR 72.48(c)(2). Specifically, the licensee failed to recognize in 10 CFR 72.48 screening No. 721042-146 that changes to thermal conditions in the annulus and DSC shell temperatures potentially impact the analyzed fuel cladding temperatures, which would require an evaluation providing the bases for determining the change does not require a license amendment pursuant to 72.48(c)(2). However, an evaluation was not performed. In the changes described in 10 CFR 72.48 evaluation No. 721042-155, the licensee failed to demonstrate the adiabatic heat up calculation, which differed from the ANSYS Fluent models in the EOS UFSAR described above, was a methodology approved by the NRC for the intended application consistent with 10 CFR 72.48(a)(2)(ii) and would not require a license amendment.

Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

The disposition of this violation closes URI: 05000346/2019004-01.

URI Unresolved Item Regarding Peak Fuel Clad Temperature 60855 During Vacuum Drying of Canister #9 URI 05000346/2019004-01

Description:

This URI is being closed to a Severity Level IV NCV in this report.

Corrective Action Reference(s): CR-2019-09156

EXIT MEETINGS AND DEBRIEFS

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

On July 27, 2021, the inspectors presented the integrated inspection results to Mr. T. Brown, Site Vice President, and other members of the licensee staff.

On May 14, 2021, the inspectors presented the radiation protection inspection results to Mr. D. Huey, General Plant Manager, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

60855 Calculations Calc No. 503948- Thermal Evaluation of EOS-37PTH in EOS-TC125 During 1

0405 the Vacuum Drying Process for the 2019 Davis Besse Dry

Cask Loading Storage Campaign

Miscellaneous 10 CFR Screening TN Americas 10 CFR Part 72. 48 Applicability Review 0

No. 721042-146 Regarding Water Boiling in the TC/DSC Annulus

CFR Screening TN Americas 10 CFR Part 72. 48 Applicability Review 0

No. 721042-155 Regarding Time Limit in Low Vacuum Pressure

71111.01 Corrective Action CR-2021-04332 Environmental Conditions Necessitate Entering RA-EP- 05/30/2021

Documents 02830 Flooding Off-Normal Procedure

Procedures RA-EP-02830 Emergency Plan Off-Normal Occurrence Procedure 06

71111.04 Corrective Action CR-2018-06716 EDG 1 SYNC Selector Switch does not Positively Lock 07/27/2018

Documents onto the DG BKR TO C1 Position

CR-2021-04913 EDG 1 Overvoltage during Monthly Run (EDG 1 0

Unavailable)

Procedures DB-OP-06316 Diesel Generator Operating Procedure 65

DB-OP-06334 Station Blackout Diesel - Diesel Generator Operating 32

Procedure

71111.05 Calculations F-FP-013.10-014 Fire Compartment BG-01, Service Water Pipe Tunnel and 02

Valve Rooms

Corrective Action CR-2019-08665 Aux Feed Pump Sliding Door 363 Safety Concern 11/19/2019

Documents CR-2021-04075 Fire Protection Identified Issue of Combustible Floor 05/19/2021

Covering Under Door 510

CR-2021-04868 Door 215 Interlock Mechanism Degraded 06/22/2021

Fire Plans PFP-AB-238 Protected Area Pre-Fire Plan, Auxiliary Feed Pump 2 05

Room - Room 238 Fire Area F

PFP-AB-505 Control Room and Adjacent Support Rooms Fire Area FF 09

PFP-IS-52 Service Water Pump Room 52 04

PFP-TB-250 Protected Area Pre-Fire Plan Service Water Pipe Tunnel 05

Room 250

Miscellaneous FHAR Hazard Analysis Report 30

71111.12 Corrective Action 2019-03616 Perform Performance GAP Analysis to Determine if there 04/18/2019

Documents is a GAP in Skills and Knowledge Regarding EDG PM

Inspection Type Designation Description or Title Revision or

Procedure Date

Scope

20-01501 Unexpected SBODG Trip during Electronic Governor 02/27/2020

Adjustment

20-01540 SBODG Fuse 2 (DC Fuel Pump) Blew during Testing 02/28/2020

21-04913 EDG 1 Overvoltage during Monthly Run 06/24/2021

21-0582 SBODG Voltage Regulator 1 Green Light Flashing 06/10/2021

221-04601 SBODG Voltage Regulators 1 and 2 Malfunctions 06/11/2021

CR-2021-04582 SBODG Voltage Regulator 1 Green Light Flashing 06/10/2021

Drawings 0200-0078-02 EDG Excitation System Interconnection Diagram 7

Miscellaneous 0200-0078-04 EDG Excitation System RA-70 Configurable Settings 0

MPR-2838 Evaluation of Reliability of Replacement EDG Excitation 1

System for Davis-Besse Nuclear Power Plant [Proprietary]

Trend Single Point Trend 06/24/2021

Procedures DB-MM-09320 Emergency and Station Blackout Diesel Engine 50

Maintenance

Work Orders 200789507 SBODG Monthly Test 0

200789645 SBODG Overspeed Trip Test 0

200810209 SBODG License Renewal Inspection 0

200817105 PM 7257 Replace Adjuster RA-70 EDG 1 06/25/2021

200857743 Troubleshoot Voltage Regulator Due to Failure 06/24/2021

601323347 Replace Voltage Regulator EDG 1 06/24/2021

71111.13 Corrective Action CR-2021-04310 Containment Entry Dose Rates were Higher than 05/28/2021

Documents Expected

CR-2021-04332 Environmental Conditions Necessitate Entering RA-EP- 05/30/2021

2830 Flooding Off-Normal Procedure

Procedures DB-OP-03013 Surveillance Test Procedure, Containment Daily 11

Inspection and Containment Closeout Inspection

NOP-OP-1007 Risk Management 34

RA-EP-02830 Emergency Plan Off-Normal Occurrence Procedure 06

71111.15 Corrective Action 2002-02203 Emergency Diesel Generator 1 Emergency Shutdown 03/13/2020

Documents 2020-02222 Diode for Relay K2 Shorted 03/14/2020

20-05188 Missed Opportunity during MRB Review of CR 2020- 06/22/2020

203

Inspection Type Designation Description or Title Revision or

Procedure Date

21-04282 EDG 1 Failed to Reach Required Voltage and Frequency 05/27/2021

during the 184 Day Test

CR-2021-04909 EDG 1 RICE Rule Violation 06/24/2021

Drawings 0200-0078-02 EDG Excitation System Interconnection Diagram 7

B15702501 Schematic Diagram Engine Control for Emergency Diesel T21

Generator 1 - 1

E559-SH 4 Emergency Diesel Generator 1 - 1 Engine Control Panel 20

Engineering NOP-CC-2003-05 ECR 03-0080-00, Replace EDG 1 - 1 Field Flash 06/18/2003

Changes Contactor (FFC)

NOP-CC-2003-16 On DCNs M-180-47-0010 and M-180-48-000 Change the 07/08/2003

Destination of the 'N' Conductor from FCC to FFC

Engineering EER-14-94013-02 SBM Selector Switches 0

Evaluations

Miscellaneous COLR Core Operating Limits Report 22

GE Manual SBM Switch Overview 0

GET-6169G Selection and Application Guide for SB Control and 0

Transfer Switches

Instruction Manual SB Control and Transfer Switches - GE Power

Management

Letter to NRC from Report No: P21-01072015 Report of Potential Failure of 01/08/2015

AZZ Nuclear GE Hitachi (GEH) SBM Type Switches per 10CFR Part 21

Letter to NRC from 10CFR21 Interim Letter, UCI Not Capable to Determine if 04/08/2014

United Controls Defect Exist General Electric SB1 Switches and HEA

International Relays

71111.18 Work Orders 200772884 Install Constant Level Oilers on DHP-1 0

71111.19 Procedures DB-PF-03291 Surveillance Test Procedure, Containment Personal and 14

Emergency Airlock Seal Leakage Test

DB-SC-03070 Emergency Diesel Generator 1 Monthly Test 42

DB-SC-03070 Emergency Diesel Generator 1 Monthly Test 43

Work Orders 200856554 PF3291 Personnel Air Lock 0

71111.22 Procedures DB-MI-03205 Surveillance Test Procedure, Channel Functional 27

Test/Calibration and Response Time of RCP Monitor

(RC3601) to SFRCS LCH 1 and RPS Channel 1

71124.02 ALARA Plans 120-5016 Insulation Work Activities in Containment Various

Inspection Type Designation Description or Title Revision or

Procedure Date

20-5032 Contractor Services Activities in Containment Various

20-5103 Under Vessel Inspections Following NI Covers Various

20-5115 Repair/Replace Gasket on the Cavity NI Covers Various

Miscellaneous Davis-Besse 1R21 Outage ALARA Report 1

Radiation Work 120-5016 Insulation Work Activities in Containment Various

Permits (RWPs) 120-5032 Contractor Services Activities in Containment Various

20-5103 Under Vessel Inspections Following NI Covers Various

20-5115 Repair/Replace Gasket on the Cavity NI Covers Various

71124.03 Calculations NOP-OP-4107-15 ALARA DAC Evaluation - Under Vessel Inspection 03/14/2020

RWP#120-5103

NOP-OP-4107-15 ALARA DAC Evaluation - Insulation Work Activities in 02/09/2020

RWP#120-6016 Containment

Corrective Action CR-2019-06640 Calculated DAC Dose Fractions Were Exceeded by more 08/09/2019

Documents than +/- 10% during DB-HP-04344

Corrective Action CR-2021-03462 Rust Identified on Self-Contained Breathing Apparatus 04/27/2021

Documents

Resulting from

Inspection

Miscellaneous Ventilation Filter Testing Program 3

GEN-M7SCBA_FEN FireHawk M7 SCBA Training 4

GEN- Industrial Safety - Respiratory Protection Training 1

PAPRHOODTL_FEN

GEN- Full-Face Respirator Practical Exercise 2

RESPPRAC_REN-

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 01/11/2020

Regulator

AMAA277770

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 08/26/2019

Regulator

AMAA277770

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 08/26/2019

Regulator

AOAA257126

Inspection Type Designation Description or Title Revision or

Procedure Date

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 08/11/2020

Regulator

AOAA257126

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 08/27/2019

Regulator

AOAA330144

MMR 2nd Stage MSA Regulator Service Report - Annual Flow Test 08/11/2020

Regulator

AOAA330144

Procedures NOP-ER-3202 Control Room Envelope Habitability (CREHAB) Program 00

RP-AA-106 Respiratory Protection Program 4

Work Orders DB-SS3146-001 CREVS Train 2 Filter Test 01/30/2019

DB-SS3302-001 CREVS Tracer Gas Test Train 2 05/17/2018

71124.05 Procedures DB-HP-00010 Radiation Measuring and Test Equipment Calibration and 12

Control Program

16