ML23156A010

NRR E-mail Capture - Calvert Cliffs - RAI License Amendment Request for Emergency Desiel Generator

ML23156A010
Person / Time
Site:	Calvert Cliffs
Issue date:	06/04/2023
From:	Sujata Goetz NRC/NRR/DORL/LPL1
To:	Para W Constellation Energy Corp
References
L-2023-LLA-0076
Download: ML23156A010 (4)

Text

From: Sujata Goetz Sent: Sunday, June 4, 2023 10:39 AM To: Para, Wendi:(Constellation Nuclear)

Subject:

Calvert Cliffs - Emergency LAR RAI ( EPID L-2023-LLA-0076)

Attachments: CAlvert Emergency LAR RAIs.docx

Dear Ms. Para,

By letter dated June 2, 2023 (Agencywide Documents Access and Management System (ADAMS) Number ML23153A098) Constellation Energy Generation, LLC (CEG), proposes a change to the Calvert Cliffs technical specifications (TS), Appendix A of Renewed Facility Operating License Nos. DPR-53 and DPR-69 for Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (CCNPP). This proposed change is being requested on an emergency basis pursuant to 10 CFR 50.91(a)(5).

The Nuclear Regulatory Commission staff has reviewed your submittal and has determined that additional information, as stated in the attachment to this email, is needed to complete its review.

Please provide your response as soon as possible, so that the NRC can meet your timeline to issue the emergency amendment.

Sincerely,

Sujata Goetz Project Manager, Calvert Cliffs and Beaver Valley

Nuclear Regulatory Commission 11555 Rockville Pike Office of Nuclear Reactor Regulations NRC/NRR/DORL/LPL1

Office 08F2 Mailroom 08-B1A Rockville, MD 20852-2738 Washington, DC 2055-0001

Hearing Identifier: NRR_DRMA Email Number: 2115

Mail Envelope Properties (MN2PR09MB546719C6AABD2EA42835AD90804CA)

Subject:

Calvert Cliffs - Emergency LAR RAI ( EPID L-2023-LLA-0076)

Sent Date: 6/4/2023 10:38:54 AM Received Date: 6/4/2023 10:38:00 AM From: Sujata Goetz

Created By: Sujata.Goetz@nrc.gov

Recipients:

"Para, Wendi:(Constellation Nuclear)" <wendi.para@constellation.com>

Tracking Status: None

Post Office: MN2PR09MB5467.namprd09.prod.outlook.com

Files Size Date & Time MESSAGE 1085 6/4/2023 10:38:00 AM CAlvert Emergency LAR RAIs.docx 27281

Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

OFFICE OF NUCLEAR REACTOR REGULATION

REQUEST FOR ADDITIONAL INFORMATION

FOR THE REVISION OF THE CALVERT CLIFF UNITS 1 AND 2,

LICENSE AMENDMENT REQUEST FOR EMERGENCY DESIEL GENERATOR

EPID: L-2023-LLA-0076

DOCKET NUMBERS 50-317 and 50-318

By letter dated June 2, 2023 (Agencywide Documents Access and Management System (ADAMS) Number ML23153A098) Constellation Energy Generation, LLC (CEG), proposes a change to the Calvert Cliffs technical specifications (TS), Appendix A of Renewed Facility Operating License Nos. DPR-53 and DPR-69 for Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (CCNPP). This proposed change is being requested on an emergency basis pursuant to 10 CFR 50.91(a)(5).

The request is a one-time extension to TS 3.7.8 Control Room Emergency Ventilation System (CREVS) Action C.1 Completion Time (CT), from seven (7) days to 16 days, for one train of the control room emergency ventilation system inoperable due to the emergency power supply for the train being inoperable.

General Design Criterion (GDC) 4, Environmental and dynamic effects design bases, requires that structures, systems, and components important to safety be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents.

GDC 5, Sharing of structures, systems, and components, requires that structures, systems, and components important to safety shall not be shared among nuclear power units unless it can be shown that such sharing will not significantly impair their ability to perform their safety functions.

GDC-19, Control room, requires a control room to be provided from which actions can be taken to operate the nuclear power unit safely under normal conditions and to maintain it in a safe condition under accident conditions, including loss-of-coolant accidents. CREVS maintains the appropriate environmental for equipment and personnel in the control room boundary, which is common to both units.

The NRC requests the following additional information to complete its review.

RAI # 1

The non-safety related 0C DG is credited as the onsite source of power for the 11 CREVS for the duration of the proposed AOT extension. The submittal states:

CCNPP has also evaluated the 0C DG for the same condition existing on the 1A DG, since they are both Societie' Alsacienne de Constructions Mechaniques De Mulhouse (SACM) DGs from the same manufacturer. CCNPP is confident t hat the 0C DG remains capable of performing its function following a loss-of-offsite power.

1

Over the past few years, the 1A DG, which is safety related and similar to the 0C DG, has experienced several failures requiring extended maintenance. Please discuss why CCNPP is confident that the 0C DG remains capable of supplying 11 CREVS and other loads if needed.

RAI #2

The LAR discusses other options should 0C DG fail to operate. Specifically, the submittal states:

Additionally, in the event of failure of the 0C diesel, the 11 CREVS can be powered by tying lower level busses in accordance with site operating procedures. Loss of all power to the CREVS would require loss of the four offsite power sources and failure of the 0C DG to start.

Please discuss the capability to power 11 CREVS from other lower level busses and the ability of those busses to carry the assumed loads.

2