ML19319A009

NRR E-mail Capture - Draft RAI for SSES Units 1 and 2 LAR to Replace ESW Piping

ML19319A009
Person / Time
Site:	Susquehanna
Issue date:	11/14/2019
From:	Sujata Goetz NRC/NRR/DORL/LPL3
To:	Sujata Goetz NRC/NRR/DORL/LPL3
References
L-2019-LLA-0004
Download: ML19319A009 (4)

Text

From: Goetz, Sujata Sent: Thursday, November 14, 2019 3:38 PM To: Goetz, Sujata

Subject:

FW: DRAFT RAI for SSES UNITS 1 AND 2 RE: LAR TO REPLACE ESW PIPING (EPID: L-2019-LLA-0004 Attachments: DORL RAI.docx

Dear Mr. Jurek,

By letter dated January 09, 2019 (Agencywide Documents Access and Management System (ADAMS)

Accession Number ML19009A431), Susquehanna Nuclear, LLC (the licensee) submitted a license amendment request (LAR) for the Susquehanna Steam Electric Station (SSES), Unit 1 and 2. The proposed amendment would permit one division of the emergency service water system (ESW) and residual heat removal service water (RHRSW) systems to be inoperable for up to 14 days to allow for ESW piping replacements.

The Nuclear Regulatory Commissions (NRC) staff has reviewed your LAR and has determined that additional information is needed to complete its review. The specific request for additional information (RAI) question is in the attachment to this email.

Please call me if you would like to schedule a clarification call.

Sujata Goetz Project Manager, Susquehanna Steam Electric Station Nuclear Regulatory Commission 11555 Rockville Pike Office of the Nuclear Reactor Regulation NRC/NRR/DORL/LPL3 Office O8F2 Mailroom O8-B1A Rockville, MD 20852-2738 Washington, DC 20555-0001 (o) 301.415.8004 (f) 301.415.3313

Hearing Identifier: NRR_DRMA Email Number: 309 Mail Envelope Properties (CH2PR09MB4005C1A4A8539DB2BBD46D0180710)

Subject:

FW: DRAFT RAI for SSES UNITS 1 AND 2 RE: LAR TO REPLACE ESW PIPING (EPID: L-2019-LLA-0004 Sent Date: 11/14/2019 3:38:11 PM Received Date: 11/14/2019 3:38:11 PM From: Goetz, Sujata Created By: Sujata.Goetz@nrc.gov Recipients:

"Goetz, Sujata" <Sujata.Goetz@nrc.gov>

Tracking Status: None Post Office: CH2PR09MB4005.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 1164 11/14/2019 3:38:11 PM DORL RAI.docx 30806 Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST REGARDING TEMPORARY CHANGE TO TECHNICAL SPECIFICATIONS 3.7.1 AND 3.7.2 SUSQUEHANNA NUCLEAR, LLC SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 DOCKET NOS.: 50-387, AND 50-388 (EPID: L-2019-LLA-0004 By letter dated January 09, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML19009A431), Susquehanna Nuclear, LLC (the licensee) submitted a license amendment request (LAR) for the Susquehanna Steam Electric Station (SSES), Unit 1 and 2. The proposed amendment would permit one division of the emergency service water system (ESW) and residual heat removal service water (RHRSW) systems to be inoperable for up to 14 days to allow for ESW piping replacements.

RAI-1

In the January 9, 2019, LAR Enclosure 1, Section 3.3 Compensatory Measures, lists ten compensatory measure Susquehanna will implement to mitigate risk during replacement of the ESW piping. Susquehanna lists an additional four actions they will take to mitigate consequences on accident on Unit 2 when replacing transformer 1X210 during initial ESW pipe replacement evolution in 2020.

The licensee proposes to add a note in Technical Specification (TS) Limited Condition for Operation (LCO) 3.7.1, Two RHRSW subsystems and the UHS [Ultimate Heat Sink] shall be OPERABLE and LCO 3.7.2, Two ESW subsystems shall be OPERABLE for Unit 1 that states:

This Completion Time is only applicable during the Unit 2 A and B ESW piping replacement while the compensatory measures identified in Section 3.3 of Enclosure 1 to letter PLA-7751 are in place. Upon completion of pipe replacement activities, this temporary extension is no longer applicable and will expire on June 25, 2027.

And in TS LCO 3.7.1 and LCO 3.7.2, for Unit 2, the proposed NOTE states:

This Completion Time is only applicable during the Unit 1 A and B ESW piping replacement while the compensatory measures identified in Section 3.3 of Enclosure 1 to letter PLA-7751 are in place. Upon completion of pipe replacement activities, this temporary extension is no longer applicable and will expire on June 25, 2026.

a. Please confirm that all fourteen compensatory measures will be taken during each time ESW pipes are replaced. If all fourteen compensatory measure are not going to be

implemented each time, please describe which compensatory measure will be implemented and under what conditions.

b. Also please provide how all these compensatory measures can be taken every time, if the compensatory measures expire at different dates.

RAI-2

The January 09, 2019, LAR Enclosure 1, page 29 response states:

The non-impacted division is capable of serving 100 percent of the heat loads for both the online and outage units during an accident. As such, there is no impact on consequence mitigation for any transient or accident.

The licensing basis includes consideration of a single failure. While the staff recognizes that the LCO is not met while in the proposed condition and action completion time, the ability to withstand single component failures is part of the safety assessment.

To provide risk insights associated with the proposed maintenance, qualitatively address the reliability of both the ESW and RHRSW subsystems by addressing the effects of credible single failures or explain how a single ESW and RHRSW pump would provide adequate flow to mitigate the loss of offsite power event in the operating unit while maintaining the other unit in cold shutdown or in the refueling modes while in one of the extended completion times (with ESW piping breached).

RAI-3

In the January 9, 2019, LAR Enclosure 1, page 23, compensatory measure 8 states:

A sump pump will be staged at the work area to prevent flooding into the reactor building in the event of torrential rain during the pipe replacement activities.

Please describe the configuration of the external flood boundary during the maintenance activity (e.g., the building penetration seal remains intact and the boundary becomes the ESW system piping inside the reactor building) and how the proposed risk management activity enhances the protection against reactor building flooding (e.g., the sump pump provides defense-in-depth by ensuring water does not flow into the ESW system piping through the breach in the system or that rain water runoff entering the building will be limited such that other required components or systems would not be adversely affected).