NRC-20-0022, Submittal of 2019 Safety Relief Valve Challenge Report, Main Steam Bypass Lines Report, and ECCS Cooling Performance Evaluation Model Changes or Errors Report

Submittal of 2019 Safety Relief Valve Challenge Report, Main Steam Bypass Lines Report, and ECCS Cooling Performance Evaluation Model Changes or Errors Report

ML20114E222
Person / Time
Site:	Fermi
Issue date:	04/23/2020
From:	Offerle M DTE Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NRC-20-0022
Download: ML20114E222 (8)

Text

DTE Energy Company 6400 N. Dixie Highway Newport, MI 48166 DTE April 23, 2020 TS 5.6.6 NRC-20-0022 10 CFR 50.46 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001 Fermi 2 Power Plant NRC Docket No. 50-341 NRC License No. NPF43

Subject:

Submittal of 2019 Safety Relief Valve Challenge Report, Main Steam Bypass Lines Report, and ECCS Cooling Performance Evaluation Model Changes or Errors Report The Fermi 2 Technical Specifications (TS) contain a requirement for submitting an annual report for safety relief valve challenges (TS 5.6.6). Enclosure 1 provides the Safety Relief Valve Challenge Report for 2019. provides the Service Life of the Main Steam Bypass Lines Report for 2019. This satisfies the commitment stated in Detroit Edison's letter to the NRC dated November 7, 1986 (VP-86-0154). provides the annual Emergency Core Cooling System (ECCS) Cooling Performance Evaluation Model Changes or Errors Report. This report is provided in accordance with 10 CFR 50.46(a)(3)(ii).

No new commitments are being made in this submittal.

Should you have any questions or require additional information, please contact me at (734) 586-5076.

Sincerely, Margaret M. Offerle Manager - Nuclear Licensing

USNRC NRC-20-0022 Page 2

Enclosure:

1. Safety Relief Valve Challenge Report 2019

2. Service Life of Main Steam Bypass Lines Report 2019

3. ECCS Cooling Performance Evaluation Model Changes or Errors Report cc: NRC Project Manager NRC Resident Office Regional Administrator, Region III

Enclosure 1 to NRC-20-0022 Fermi 2 NRC Docket No. 50-341 Operating License No. NPF-43 Safety Relief Valve Challenge Report 2019 to NRC-20-0022 Page 1 Safety Relief Valve Challenges (January 1, 2019 to December 31, 2019)

There were no instances in 2019 where reactor pressure was high enough to require Safety Relief Valve (SRV) actuation. There were also no instances in 2019 where an SRV actuation was demanded by an automatic logic system.

Enclosure 2 to NRC-20-0022 Fermi 2 NRC Docket No. 50-341 Operating License No. NPF-43 Service Life of Main Steam Bypass Lines Report 2019 to NRC-20-0022 Page 1 Service Life of Main Steam Bypass Lines (through December 31, 2019)

In accordance with Detroit Edisons letter to the NRC dated November 7, 1986 (VP-86-0154),

the cumulative time the main steam bypass lines are operated with the bypass valves between 30 and 45 percent open will be reported annually. A cumulative value of 100 days is not to be exceeded without prior NRC notification.

As discussed in Detroit Edisons letter number VP-86-0154, the bypass lines are acceptable for safe operation when operated within the 100-day constraint.

As of December 31, 2019, the main steam bypass lines cumulative usage was 47.74 days.

Enclosure 3 to NRC-20-0022 Fermi 2 NRC Docket No. 50-341 Operating License No. NPF-43 ECCS Cooling Performance Evaluation Model Changes or Errors Report to NRC-20-0022 Page 1 Emergency Core Cooling System (ECCS) Cooling Performance Evaluation Model -

Analysis of Record On April 8, 2020, DTE Energy submitted a re-analysis of the Loss of Coolant Accident (LOCA) using TRACG-LOCA (Reference 1). This re-analysis established a new licensing basis Peak Clad Temperature (PCT) of 1980°F for GE14 fuel and 2150°F for GNF3 fuel which are both associated with the limiting small break LOCA.

ECCS Cooling Performance Evaluation Model Changes or Errors Since the time of the submittal of the analysis of record identified above, General Electric -

Hitachi (GEH) and Global Nuclear Fuel (GNF) have issued the following notifications which indicated that changes had been made in the ECCS-LOCA analyses inputs that affect Fermi 2.

2020-01 April 14, 2020 Reference 2 A tabulated summary of the impacts of all errors is provided below.

Current LOCA Model Assessment Description GE14 PCT GNF3 PCT 10CFR 50.46 Baseline Licensing Basis PCT PCT=1980°F PCT=2150°F (Reference 1) 10 CFR 50.46 Notification Letter 2020-01 dated April PCT = 0°F PCT = 0°F 14, 2020, PRIME Coding Errors for Zircaloy Irradiation Growth and Zr Barrier Thermal Conductivity as input to ECCS LOCA Analyses (Reference 2)

Net PCT PCT=1980°F PCT=2150°F

Reference:

1. DTE Letter to USNRC, Submittal of Plant Specific Emergency Core Cooling System (ECCS) Evaluation Model Reanalysis, NRC-20-0010, dated April 8, 2020 (ML20100B567)

2. General Electric-Hitachi, 10 CFR 50.46 Notification Letter 2020-01, dated April 14, 2020.