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Triennial Inspection of Evaluation of Changes, Tests and Experiments Baseline Inspection Report 05000341/2021011
	ML21235A013
Person / Time
Site:	Fermi
Issue date:	08/25/2021
From:	Richard Skokowski; Engineering Branch 3
To:	Peter Dietrich; DTE Electric Company
References
	IR 2021011
	Download: ML21235A013 (16)
	v • d • e

SUBJECT:

FERMI POWER PLANT, UNIT 2 - TRIENNIAL INSPECTION OF EVALUATION OF CHANGES, TESTS AND EXPERIMENTS BASELINE INSPECTION REPORT 05000341/2021011

Dear Mr. Dietrich:

On July 14, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Fermi Power Plant, Unit 2 and discussed the results of this inspection with Mr. M. Caragher, Director Nuclear Engineering, and other members of your staff. The results of this inspection are documented in the enclosed report.

One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.

If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; the Director, Office of Enforcement; and the NRC Resident Inspector at Fermi Power Plant, Unit 2.

If you disagree with a cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; and the NRC Resident Inspector at Fermi Power Plant, Unit 2.

August 24, 2021 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, Richard A. Skokowski, Chief Engineering Branch 3 Division of Reactor Safety Docket No. 05000341 License No. NPF-43

Enclosure:

As stated

Inspection Report

Docket Number:

05000341

License Number:

NPF-43

Report Number:

05000341/2021011

Enterprise Identifier:

I-2021-011-0006

Licensee:

DTE Electric Company

Facility:

Fermi Power Plant, Unit 2

Location:

Newport, MI

Inspection Dates:

June 21, 2021 to July 14, 2021

Inspectors:

M. Holmberg, Senior Reactor Inspector

V. Meghani, Reactor Inspector

J. Neurauter, Senior Reactor Inspector

Approved By:

Richard A. Skokowski, Chief

Engineering Branch 3

Division of Reactor Safety

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a triennial inspection of evaluation of changes, tests and experiments baseline inspection at Fermi Power Plant, Unit 2, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.

List of Findings and Violations

Inadequate Design Verification for Replacement HPCI Suction Strainer Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000341/2021011-01 Open/Closed

[H.4] -

Teamwork 71111.17T The inspectors identified a Green finding and associated Non-cited Violation (NCV) of 10 CFR Part 50, Appendix B, Criterion III for the licensees failure to establish measures to assure that the design basis for the high pressure coolant injection (HPCI) suction strainer was correctly translated into specifications, drawings, procedures, and instructions.

Specifically for the replacement HPCI system suction strainer, the licensee failed to consider the effects of suppression chamber (torus) hydrodynamic loads specified in Paragraph 3.8.2.4.2 and Section 3.9.2.2.1 of the Fermi Unit 2 Updated Final Safety Analysis Report (UFSAR) and also failed to evaluate changes to the original suction strainer welds.

Additional Tracking Items

None.

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), inspectors were directed to begin telework. In addition, 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

71111.17T - Evaluations of Changes, Tests, and Experiments Sample Selection (IP Section 02.01)

Main article: IP 71111.17

The inspectors reviewed the following evaluations, screenings, and/or applicability determinations for 10 CFR 50.59 from June 21, 2021, through July 14, 2021.

(1) Evaluation 20-0027, EDP 80131 and LCR 20-007-UFS Torus Coating Modification

(2) Evaluation 20-0074, Emergency Operating Procedure/Sever Accident Guidance Update to BWROG Emergency Planning Guidance/Sever Accident Guidance Revision 4 Volume 1 to VI, Appendix A, B, C and Technical Support Guidelines Revision 1

(3) Evaluation 20-0122, Update of DC-6132 Volume I for Effects of 24-Month Cycle Operation and Impact on Main Control Room Unfiltered Air Infiltration

(4) Evaluation 18-0286, LCR 20-044-UFS CARD 16-26536 - 2016 CBDI - EDG 12 & 14 LOP/ LOCA Minimum Voltage Values

(5) Evaluation 18-0280, EDP 80071 Auto Closure of Torus to Reactor Building Vacuum Breaker Isolation Valve T2300F409 & T2300F410 & TSR 38087/LCR

(6) Evaluation 19-0004, Resolution of Emergency Core Cooling Suction Strainer Modification Calculation Deficiencies

(7) Evaluation 19-0026, TSR-38095 REV 0 GNF3 New Fuel Introduction

(8) Evaluation 19-0208, TSR-38170 - GNF3 New Fuel Receipt

(9) Evaluation 19-0264, Implementation of the Change in Methodology for the Anticipated Transient Without Scram Event

(10) Screening 21-0024, Residual Heat Removal System

(11) Screening 20-0155, Post Coating Margin to DC-5979 Volume I

(12) Screening 20-0080, Main Turbine Generator Rotor Replacement

(13) Screening 20-0011, Cycle 21 Reload Core Design and Licensing UFSAR Update

(14) Applicability Determination DSN 37374, Changes to Thermal Transients and Number of Cycles

(15) Screening 20-0021, Update Standby Liquid Control System Design Basis Documents

(16) Screening 20-0046, Replacement of Residual Heat Removal Service Water Valve E1150F068A

(17) Screening 20-0140, Issue Revision to Design Specification 3071-360

(18) Applicability Determination DSN 60093, G1100F141 Air Operated Valve Replacement

(19) Applicability Determination DSN 70097, Replacement of High-Pressure Coolant Injection Suction Strainer

(20) Screening 18-0244, As-Built Support W-E51-5078-G17

(21) Screening 19-0019, Evaluation for Scaffold Supported Temporary Shielding

(22) Screening 19-0155, 10CFR50.59 Review of Temporary Laydown Area Established for >90 Days

(23) Screening 20-0127, Torus Room Permanent Shielding Along Reactor Water Cleanup Line

(24) Applicability Determination DSN 38036, Administrative Changes to Heavy Load Rigging Specification 3071-375

INSPECTION RESULTS

Inadequate Design Verification for Replacement HPCI Suction Strainer Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000341/2021011-01 Open/Closed

[H.4] -

Teamwork 71111.17T The inspectors identified a Green finding and associated Non-cited Violation (NCV) of CFR Part 50, Appendix B, Criterion III for the licensees failure to establish measures to assure that the design basis for the high pressure coolant injection (HPCI) suction strainer was correctly translated into specifications, drawings, procedures, and instructions.

Specifically for the replacement HPCI system suction strainer, the licensee failed to consider the effects of suppression chamber (torus) hydrodynamic loads specified in Paragraph 3.8.2.4.2 and Section 3.9.2.2.1 of the Fermi Unit 2 Updated Final Safety Analysis Report (UFSAR) and also failed to evaluate changes to the original suction strainer welds.

Description:

In DSN 70097, the licensee identified that the HPCI suction strainer was damaged and needed to be replaced. The licensee utilized a contractor to reverse engineer an equivalent replacement strainer based on the original strainer, Chicago Bridge & Ironworks (CBI)drawings 227 and 228 as modified in Nuclear Technologies (Nutech) drawing DET-19-067.

To support this activity, the licensees contractor developed new drawings (DSN 2700) for fabrication of the replacement HPCI strainer with critical dimensions and material identical or similar to the original strainer. One exception was that the replacement HPCI strainer could be fabricated using a lower strength stainless steel material, SA240 Type 304 or Type 304L.

To verify the replacement strainer design dimensions and acceptance of the lower strength material, a different licensee contractor completed a stress analysis of the replacement HPCI strainer design using computer based finite element analysis that considered differential pressure and seismic loads at operating temperature (reference calculation C-7513-00-01).

Because the replacement HPCI suction strainer was fabricated with similar material, and weight, and the analysis results as documented in calculation C-7513-00-01 were acceptable, the licensee determined the replacement strainer design was equivalent to the original HPCI suction strainer.

The inspectors identified that in calculation C-7513-00-01, the licensee had not considered torus internal hydrodynamic loads applicable to design basis loss-of-coolant accident (LOCA)-related and safety relief valve (SRV) discharge-related loading events for the Fermi Mark 1 containment. Specifically, in UFSAR Paragraph 3.8.2.4.2 it identifies that The torus-shaped suppression chamber is designed as an axisymmetric shell of revolution.

Analysis techniques similar to those used for the drywell were applied in the original design of the suppression chamber. The suppression chamber design has subsequently been reevaluated and modified for the effects of the LOCA-related loads and SRV discharge-related loads defined by NUREG-0661, Mark I Containment Long-Term Program, Safety Evaluation Report, July 1980, and General Electric Report NEDO-21888, "Mark I Containment Program Load Definition Report," Revision 2, November 1981. The loads, load application methods, and structural analysis techniques applied in the suppression chamber reevaluation are described in Nuclear Technologies (Nutech) Report DET-04-028-1,2,3,4,5, Enrico Fermi Atomic Power Plant, Unit 2, Plant Unique Analysis Report, Revision 1, November 1983, and Nutech Report DET-19-076-6, Enrico Fermi Atomic Power Plant, Unit 2, Plant Unique Analysis Report for Torus Attached Piping, Revision 0, June 1983. The criteria set forth in NUREG-0661 and the original containment design specifications have been applied as a basis for acceptance of the analysis methods and the suppression chamber design. In addition, UFSAR Section 3.9.2.2.1 identifies that the structural analyses for large and small-bore torus-attached piping, piping supports, and related equipment are described in the Plant Unique Analysis Report and DC-6003 Vol I, Evaluation of New ECCS Suction Strainers on Existing TAP Analysis for Torus-Attached Piping (TAP) and references the Nutech Report DET-19-076-6. Because, the licensee had not applied the hydrodynamic loads identified in these design basis documents, the inspectors could not determine that the replacement HPCI suction strainer design was equivalent to the original strainer.

As a result, the licensee entered this concern into to the corrective action program (CAP) as CARD 21-25514, HPCI Strainer Evaluation in EDP 70097 Does Not Factor Design Basis Loading Conditions. In this CARD, the licensee stated, Since the stress margins associated with the current engineering evaluation are substantially large, and since not all of the suction strainer components have reduced strength, it is concluded by Engineering judgement that the new HPCI suction strainer will be able to perform its intended design function during a postulated design basis accident. However, the stress margins (the difference between calculated stresses and material allowable stresses) are currently unknown, and therefore, further evaluation is required to both quantify and confirm that the margin is indeed positive (calculated stresses < max allowable stresses). The inspectors considered this a reasonable basis to conclude that the replacement HPCI strainer was operable and capable of supporting the HPCI system design functions during a postulated design basis accident.

During followup of CARD 21-25514, the licensee completed a revised analysis that included the torus internal hydrodynamic loads and identified an overstressed condition at the location where strainer stiffener bars were tack welded to the perforated sheet material. The licensee documented this issue in CARD 21-25645 and believed that this condition existed since original construction but was missed in the original design basis torus internal hydrodynamic loading evaluation of the HPCI suction strainer. As a result, the inspectors performed additional reviews of the replacement strainer fabrication weld details for conformance to the original strainer and identified a change to the weld that attached the reinforcement plate to the perforated sheet. Specifically, in drawing DET-19-067 a continuous top-to-bottom fillet weld was identified but in drawing 2700 a top-to-bottom intermittent tack weld on 2-inch centers was identified. In addition, for the replacement strainer, drawing 2700 specified a perforated sheet overlap of 1/2 inch, with intermittent tack welds inside and outside on 2-inch centers, which was not consistent with the original HPCI strainer, which was fabricated with a full weld along this seam (e.g. no overlap present). However, the inspectors noted that the original CB&I drawing 228 lacked weld details for this perforated sheet seam. In addition, the reinforcement welds to the original strainer were designed per the ASME Section III Code Subsection NF as identified in calculation 50.301.2320 and the inspectors were not able to identify specific rules in Subsection NF or Subsection NC for welding 14 gauge perforated sheet steel that would ensure the specified weld configuration had sufficient structural capacity for torus internal hydrodynamic design loads (i.e., intermittent tack welds are normally used for fit-up prior to final welding and are not normally considered structural welds). The licensee entered these weld discrepancies into the CAP (CARD 21-26053 and CARD 21-25645) and determined that the operability basis established in CARD 21-25514 remained sufficient to bound these additional issues.

Corrective Actions: The licensee performed evaluations of the identified concerns and determined the replacement HPCI strainer was operable in its current configuration. Also, the licensee established actions to restore the replacement HPCI suction strainer stress margins in accordance with design basis Code requirements.

Corrective Action References: CARDS 21-25514, 21-25522, 21-25645, 21-26053, 21-26055, and 21-26056

Performance Assessment:

Performance Deficiency: The inspectors determined that the licensees failure to establish measures to assure that the design basis for the HPCI suction strainer was correctly translated into specifications, drawings, procedures, and instructions was contrary to 10 CFR Part 50, Appendix B, Criterion III and was a performance deficiency. Specifically, the licensee failed to apply and verify the design basis hydrodynamic loading for analysis of the replacement HPCI suction strainer and failed to evaluate changes to original HPCI suction strainer fabrication welds.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Design Control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. The inspectors also compared the performance deficiency with the examples listed in IMC 0612, Power Reactor Inspection Reports, Appendix E, Example of Minor Issues and identified that the performance deficiency was more than minor using example 3.a. Specifically, the failure to ensure the replacement HPCI suction strainer configuration was based on supporting calculations that included the Mark I containment design loads resulted in a component that was not demonstrated to be adequate to meet the design basis requirements. Therefore, without objective evidence, reasonable assurance did not exist that the strainer availability and reliability would be maintained, and this deficiency will require substantial revision to the existing design calculations and/or replacement HPCI suction strainer rework to ensure that the strainer design including fabrication welds is adequate to withstand the torus hydrodynamic loads.

Significance: The inspectors assessed the significance of the finding using Appendix A, The Significance Determination Process (SDP) for Findings At-Power.

The inspectors determined the finding was of very low safety significance (Green) because the inspectors answered YES to question A.1 in Exhibit 2. Specifically, the licensee provided reasonable assurance that the operability/functionality of the strainer and HPCI system was maintained under the required loading.

Cross-Cutting Aspect: H.4 - Teamwork: Individuals and work groups communicate and coordinate their activities within and across organizational boundaries to ensure nuclear safety is maintained. Specifically, the licensee did not establish adequate communication between the contractor that reverse engineered the original HPCI suction strainer, and the contractor that performed stress analysis of the replacement HPCI suction strainer to ensure the design basis for components subjected to torus internal hydrodynamic loads was maintained.

Enforcement:

Violation: Title 10 CFR Part 50, Appendix B, Criterion III, Design Control," requires in part, that measures shall be established to assure that applicable regulatory requirements and the design basis, as defined in 10 CFR 50.2 and as specified in the license application, for those structures, systems, and components are correctly translated into specifications, drawings, procedures and instructions. In addition, design control measures shall provide for verifying or checking the adequacy of design, such as by the performance of design reviews, by the use of alternate or simplified calculational methods, or by the performance of a suitable testing program.

Contrary to the above, on August 16, 2018, the licensee failed to establish measures to assure that the applicable regulatory requirements and design basis for the HPCI suction strainer were correctly translated into procedures or instructions and failed to verify or check the design adequacy of the safety-related HPCI suction strainer replacement. Specifically, in supporting calculation C-7513-00-01, the licensee failed to consider torus internal hydrodynamic design basis loads, as identified in UFSAR Sections 3.8.2.4.2 and 3.9.2.2.1, and also failed to evaluate changes to the original HPCI suction strainer welds.

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

EXIT MEETINGS AND DEBRIEFS

The inspectors confirmed that proprietary information was controlled to protect from public disclosure.

On July 14, 2021, the inspectors presented the triennial inspection of evaluation of changes, tests and experiments baseline inspection results to Mr. M. Caragher, Director Nuclear Engineering, and other members of the licensee staff.

On June 25, 2021, the inspectors presented the triennial inspection of evaluation of changes, tests and experiments inspection results to Eric Olsen, Site Vice President, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

50.301.1381

Torus Attached Piping Penetration Analysis (Load

Development for Suction Strainers)

50.301.2320

Suction Strainer Reinforcement Stress Analysis

C-7513-00-01

ASME Code Evaluation of Fermi 2 Suppression Pool

Strainer

DC-5227 Vol 1

DCD 1

Seismic Qualification of New Fuel Uprighting Stand

FER 175797

Hydrodynamic Load Factors Fermi Nuclear Generating

Station Unit 2

Calculations

URS 148 C 1

Fermi 2 HPCI Suction Strainer Operability Evaluation

CARD 12-22492

Variance from BWRVIP-205

03/30/2012

CARD 16-26536

EDG 12 & 14 LOP/ LOCA Minimum Voltage Values Do Not

Meet Regulatory Guide 1.9 Criteria

08/17/2016

CARD 18-26261

Actuator of the F054 Interference

08/17/2018

CARD 19-20901

Trend CARD - Documentation

2/06/2019

CARD 19-21369

Technical Specification 3.1.7 Figure 1, SLC Tank Level

Limits Potentially Non-Conservative

2/21/2019

CARD 19-24099

Evaluate Potential Impacts CFR50.59 Program due to

Revision 1 to Regulatory Guide 1.187

05/28/2019

CARD 19-26263

50.59 for RHR Div 1 Decant Pump Being Removed Greater

than 90 Days

08/20/2019

CARD 19-27432

Calculations Establishing Seismic II/I Qualifications for New

Fuel Uprighting Machine and Inspection Stand Invalid

10/01/2019

CARD 20-21633

Transient Permit at 90 Days End of Life, and No 50.59

Review Completed

2/13/2020

CARD 20-25435

Status of Thermal Recombiner System Needs to Be

Reconciled with 10 CFR 50.59, 10 CFR 50.71(e), and

TS 5.5.2

04/30/2020

CARD 20-26999

Torus Recoat - Update to Unqualified Coatings Log

06/17/2020

Corrective Action

Documents

CARD 20-31725

50.59 Evaluation Not Completed Per Procedure MLS14

within the 90-Day Timeframe For Torus Equipment

10/28/2020

71111.17T

Corrective Action

CARD 21-25514

21 NRC 50.59 Inspection - HPCI Strainer Evaluation in

06/22/2021

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

EDP 70097 Does Not Factor Design Basis Loading

CARD 21-25522

21 50.59 Inspection: DEC 70097 HPCI Suction Strainer

Replacement Did Not Meet Requirements of Design

Equivalent Change per MES90

06/22/2021

CARD 21-25523

Use of Silicone in CCHVAC May Not Be Addressed by an

Aging Management Program

06/22/2021

CARD 21-25525

21 50.59 Inspection: Radiation Shielding Not Evaluated

per 65.000.303

06/21/2021

CARD 21-25547

21 NRC 50.59 Inspection - Isometric Drawing

6BM721-4188-1 Seismic Classification Update Required

06/23/2021

CARD 21-25645

21 NRC 50.59 Inspection - Original HPCI Strainer Does

Not Evaluate Stress on Tack Welded Components

06/25/2021

CARD 21-26053

21 NRC 50.59 Inspection - EDP 70097 Did Not Evaluate

Smaller Welds on HPCI Suction Strainer Basket

07/09/2021

CARD 21-26055

21 NRC 50.59 Inspection - EFA-E41-21-007 and CARD

21-25645 Did Not Envelope All Material Used in the

Replacement HPCI Suction Strainer

07/09/2021

Documents

Resulting from

Inspection

CARD 21-26056

21 NRC 50.59 Inspection - Incorrect Construction /

Design Code Used during the HPCI Suction Strainer

Replacement Project

07/09/2021

CB&I 228

Strainers

DET 19 076

Page 1

Nutech Engineers Sketch - Details of Suction Strainers