ML20013C728

NRR E-mail Capture - Final RAI Regarding Surry'S TS One-Time 14-Day AOT RSST Cable Replacement LAR

ML20013C728
Person / Time
Site:	Surry
Issue date:	01/09/2020
From:	Vaughn Thomas NRC/NRR/DORL/LPL4
To:	Geoffrey Miller Dominion Generation
References
Download: ML20013C728 (3)

Text

From: Thomas, Vaughn Sent: Thursday, January 9, 2020 3:35 PM To: gary.d.miller@dominionenergy.com Cc: Miller, Ed

Subject:

Final RAI Regarding Surry's TS One-Time 14-Day AOT RSST Cable Replacement LAR Attachments: Final RAI Regarding Surry's TS One-Time 14-Day AOT RSST Cable Replacement.docx

Gary, The attached file constitutes the staffs issuance of the final RAI to Surry pertaining to the subject LAR. Per our clarification call today, January 9, 2020, the licensee agreed to provide its response to the staff RAI within 30 days from todays date, January 9, 2020. Additionally, the licensee intends to summarize its response to the following question as part of its response to the staff RAI.

In the LAR, the licensee stated, To facilitate the replacement of the RSST C 5 kV cables to Transfer Bus F, RSST C must be removed from service. Thus, the electrical configuration of the plant for this modification is the same as it was for the RSST C replacement completed during the Unit 2 fall 2018 RFO. A temporary 21-day AOT for the RSST C replacement was approved by the NRC in TS Amendments 293/293 dated October 5, 2018.

The TS Amendments 293/293 dated October 5, 2018 (ML18621A099) was meant both for replacement of RSST C and associated cabling. Please clarify whether or not the replacement of associated cabling was completed during previous Unit 2 fall 2018 RFO, and whether the replacement of cables proposed in this LAR are different from those mentioned in previous amendment.

Thanks Vaughn Thomas, Project Manager Plant Licensing Branch 4 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Vaughn.Thomas@nrc.gov 301-415-5897

Hearing Identifier: NRR_DRMA Email Number: 385 Mail Envelope Properties (CH2PR09MB42660B88219FF0A1B766910FF4390)

Subject:

Final RAI Regarding Surry's TS One-Time 14-Day AOT RSST Cable Replacement LAR Sent Date: 1/9/2020 3:35:28 PM Received Date: 1/9/2020 3:35:00 PM From: Thomas, Vaughn Created By: Vaughn.Thomas@nrc.gov Recipients:

"Miller, Ed" <Ed.Miller@nrc.gov>

Tracking Status: None "gary.d.miller@dominionenergy.com" <gary.d.miller@dominionenergy.com>

Tracking Status: None Post Office: CH2PR09MB4266.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 1476 1/9/2020 3:35:00 PM Final RAI Regarding Surry's TS One-Time 14-Day AOT RSST Cable Replacement.docx 40814 Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

SURRY UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING ONE-TIME 14-DAY ALLOWED OUTAGE TIME FOR REPLACEMENT OF 5 KV CABLES ASSOCIATED WITHRESERVE STATION SERVICE TRANSFORMER C (EPID NO. L-2019-LLA-0244)

By application dated October 30, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML19309D199, Virginia Electric and Power Company (Dominion Energy Virginia) (the licensee) requested a license amendment to revise the Surry Power Station (Surry) Units 1 and 2 Technical Specification (TS) 3.16 Emergency Power System. Specifically, the license amendment request (LAR) would allow a one-time extension of the Allowed Outage Time (AOT) in TS 3.16, Action B.2, from 7 days to 14 days. The licensee requested a temporary 14-day AOT to allow replacement of the 5 kilo-Volt (KV) cables from Reserve Station Service Transformer C (RSST C) to Transfer Bus F during the Surry Unit 2 spring 2020 refueling outage (RFO). The RSST C 5 KV cables provide distribution of reliable offsite power from RSST C to Transfer Bus F, which supplies the 1H and 2J emergency buses.

The RSST C and associated cables to Transfer Bus F provide offsite power to both units.

Therefore, the TS change request applies to both units.

The NRC staff has identified the need for the following additional information to complete the review of LAR:

Applicable Regulatory Requirements Title 10 of the Code of Federal Regulations (10 CFR) Part 50.36(c)(2) provides the requirement for the establishment of TS limiting conditions for operation (LCO). Specifically, paragraph 50.36(c)(2)(ii) requires that a TS LCO of a nuclear reactor be established for each item meeting one or more of the criteria listed. For this LAR, Criterion 3 is applicable and states: A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a DBA or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.

Request for Additional Information (RAI)

RAI # 1 In the LAR, Attachment 1, Page 9, the licensee stated that during the temporary 14-day AOT, the one-time operating restrictions will be as follows: (1) Two Unit Load Shed Circuit (LSR1) will be defeated, and (2) Auto Start Blocking Circuit (LSR2) will be in operation.

Please provide a detailed description of the functions of the (1) Two Unit Load Shed Circuit (LSR1), and (2) Auto Start Blocking Circuit (LSR2). Also, explain why the operating restrictions on these circuits are considered necessary during the temporary 14-day AOT.