ML20167A253
| ML20167A253 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 06/15/2020 |
| From: | Marshall M Plant Licensing Branch 1 |
| To: | Mascitelli F Exelon Generation Co, Exelon Nuclear |
| Marshall M, NRR/DORL/LPLI, 415-2871 | |
| References | |
| EPID L-2019-LLA-0281 | |
| Download: ML20167A253 (2) | |
Text
From:
Marshall, Michael To:
Mascitelli, Francis J:(Exelon Nuclear)
Cc:
Danna, James
Subject:
Calvert Cliffs Nuclear Power Plant, Units 1 and 2 - Second Request for Additional Information Regarding License Amendment Request Concerning Emergency Diesel Generator Surveillance Requirements for Frequency and Voltage Tolerances (EPID L-2019-LLA-0281)
Date:
Monday, June 15, 2020 2:02:00 PM Hello Frank,
By letter dated December 11, 2019 (Agencywide Documents Access and Management System Accession No. ML19346E536), Exelon Generation Company, LLC (Exelon; licensee) submitted license amendment requests (LAR) for Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (Calvert Cliffs). The proposed amendments would revise certain frequency and voltage acceptance criteria for steady-state emergency diesel generator surveillance testing in Calvert Cliffs Technical Specification Section 3.8.1, AC Sources -
Operating. The calculations supporting the request were revised using methodology described in WCAP-17308-NP-A, Rev. 0, "Treatment of Diesel Generator (DG) Technical Specification Frequency and Voltage Tolerances, dated July 2017.
The U.S. Nuclear Regulatory Commission staff has reviewed the information provided in the LAR and has determined that additional information is needed to complete its review.The request for additional information was discussed with you on May 27 and June 12, 2020, and it was agreed that your response would be provided within 30 days of the date of this email.
Below is the NRC staffs second request for additional information. The first request for additional information was emailed to you on June 5, 2020. Separately, a request for confirmatory information will be sent to you through a separate email.
REQUEST FOR ADDITIONAL INFORMATION
Section 50.36, Technical specifications, of Title 10 of the Code of Federal Regulations (10 CFR) describe the requirements related to the content of the technical specifications (TS).
Pursuant to 10 CFR 50.36(c), TS are required to include item surveillance requirements (SR). Surveillance requirements relating to test, calibration, or inspection need to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the limiting conditions for operation will be met. The proposed changes in this LAR relate to the SRs.
- 2. The lower discharge pressures resulting from the proposed low-end frequency tolerance (59.25 Hertz) could cause low pressure switches to trip. Similarly, the higher discharge pressure resulting from the proposed high-end frequency tolerance (60.75 Hertz) could cause relief valves to lift on affected discharge piping. The licensee did not provide information that addresses whether the proposed frequency tolerance change could cause low pressure switches associated with affected pumps (if equipped) to trip or relief valves located on the discharge piping of affected pumps to lift.
Please discuss whether or not any low pressure switches associated with affected pumps will trip or whether any relief valves located on the discharge piping of affected pumps will lift due to the pressures at the low-end (59.25 Hertz) and high-end (60.75
Hertz) proposed frequency tolerance. If a low pressure switch could trip or a relief valve could lift, explain how the affected pumps will continue to perform their design functions.
Best Regards, Michael L. Marshall, Jr.
Senior Project Manager
Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
301-415-2871
Docket No. 50-317 and 50-318