ML18143A397

Oyster Creek Nuclear Generating Station - 10 CFR 50.46 Annual Report

ML18143A397
Person / Time
Site:	Oyster Creek
Issue date:	05/23/2018
From:	David Helker Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RA-18-055
Download: ML18143A397 (7)

Text

Exelon Generation,, RA-18-055 May 23, 2018 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 NRC Docket No. 50-219

Subject:

1 O CFR 50.46 Annual Report 10 CFR 50.46

Reference:

Letter from David P. Helker, Exelon Generation Company, LLC to U.S. Nuclear Regulatory Commission, "10 CFR 50.46 Annual Report," dated May 23, 2017 The purpose of this letter is to transmit the annual 1 O CFR 50.46 reporting information for Oyster Creek Nuclear Generating Station (OCNGS). The previous annual 50.46 report for OCNGS submitted on May 23, 2017 (Reference), provided the cumulative Peak Cladding Temperature (PCT) errors for the most recent fuel designs. Since the referenced annual report was issued, two vendor notifications of Emergency Core Cooling System (ECCS) model errors/changes that are applicable to OCNGS have been issued. These notifications have no impact on the OCNGS LOCA analysis. Also, no related changes or modifications have occurred at OCNGS that affect the assumptions of the ECCS analyses. Two attachments are included with this letter that provide the current OCNGS 1 O CFR 50.46 status. Attachment 1, "Peak Cladding Temperature Rack-Up Sheet," provides information regarding the PCT for the limiting Loss of Coolant Accident (LOCA) analysis evaluations for OCNGS. Attachment 2, "Assessment Notes," contains a detailed description for each change or error reported. There are no regulatory commitments contained in this letter. Should you have any questions concerning this letter, please contact Mr. David J. Distel at (610} 765-5517. Respectfully, David P. Helker Manager, Licensing and Regulatory Affairs Exelon Generation Company, LLC May 23, 2018 U.S. Nuclear Regulatory Commission Page 2 Attachments: 1) Peak Cladding Temperature Rack-Up Sheet 2) Assessment Notes cc: USNRC Region I, Regional Administrator USNRC Senior Resident Inspector, OCNGS USNRC Senior Project Manager, OCNGS Manager, Bureau of Nuclear Engineering, New Jersey Department of Environmental Protection Mayor of Lacey Township, Forked River, NJ ATTACHMENT 1 10 CFR 50.46 "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors" Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of May 23, 2018 Peak Cladding Temperature Rack-Up Sheet Oyster Creek Nuclear Generating Station Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of May 23, 2018 Peak Cladding Temperature Rack-Up Sheet for OCNGS Attachment 1 Page 1 of 2 PLANT NAME: ECCS EVALUATION MODEL: Oyster Creek Nuclear Generating Station (OCNGS) SAFER/CORCUPRIME REPORT REVISION DATE: 05/23/2018 CURRENT OPERATING CYCLE: 26 ANALYSIS OF RECORD CALCULATIONS Calculations: 1. Report 0000-0098-3503-R2, Revision 2, "Oyster Creek Generating Station GNF2 LOCA Evaluation," GEH Nuclear Energy, dated November 201 O 2. Report 002N6964 Rev 0, "Supplemental Reload Licensing Report for Oyster Creek Reload 26 Cycle 26," dated August 2016 Fuel: Limiting Fuel Type: Limiting Single Failure: Limiting Break Location: Limiting Break Size GNF2 GNF2 ADS Valve Recirculation Discharge Line 4.66 ft2 Double-Ended Guillotine (DEG) Reference Peak Cladding Temperature (PCT) for GNF2 Fuel: 2175°F Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of May 23, 2018 Peak Cladding Temperature Rack-Up Sheet for OCNGS MARGIN ALLOCATION A. PRIOR LOCA MODEL ASSESSMENTS 1 O CFR 50.46 Report dated May 23, 2017 (Note 1) NET PCT B. CURRENT LOCA MODEL ASSESSMENTS Notification 2017-01 (Note 2) Notification 2017-02 (Note 2) Total PCT Change from Current Assessments (see note 2) Cumulative PCT Change from Current Assessments NET PCT Attachment 1 Page 2 of 2 GNF2: 0°F GNF2: 2175°F GNF2: 0°F GNF2: 0°F GNF2: = 0°F GNF2: = 0°F GNF2: 2175°F ATTACHMENT 2 10 CFR 50.46 "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors" Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of May 23, 2018 Assessment Notes Oyster Creek Nuclear Generating Station Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of May 23, 2018 Assessment Notes, OCNGS 1. Prior LOCA Model Assessment Attachment 2 Page 1 of 1 A new LOCA/MAPLHGR analysis for fresh GNF2 fuel was performed for Cycle 26, and restated/confirmed the MAPLHGRs for the existing GNF2 fuel (Reference 1 ). These analyses maintained the licensing basis PCT at 2175°F and superseded all prior LOCA assessments. This analysis incorporated all ECCS/LOCA methodology errors and changes resolved at that time (as of August 2016). 2017 Annual 1 OCFRS0.46 Report (Reference 2) documents no new notifications as of May 2017. [Reference 1: GNF Report 002N6964 Rev. 0, "Supplemental Reload Licensing Report for Oyster Creek Reload 26 Cycle 26," dated August 2016.] [Reference 2: Letter from David P. Helker (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "1 O CFR 50.46 Annual Report," dated May 23, 2017.] 2. Current LOCA Model Assessment Since the issuance of the previous Annual Report (Reference 2 in Note 1 ), two new error notifications that are applicable to the Oyster Creek LOCA analysis, 2017-01 and 2017-02, were received from the fuel vendor. Notification 2017-01, dated June 12, 2017, addresses an incorrect assumption of lower tie plate leakage with an estimated PCT impact of 0°F for GNF2 fuel. Notification 2017-02, dated August 2, 2017, addresses a change in the fuel rod upper plenum modeling with an estimated PCT impact of 0°F for GNF2 fuel.