ML20323A066

Summary of October 28, 2020, Teleconference with Tennessee Valley Authority Regarding Planned License Amendment Request for Technical Specification Surveillance Requirement 3.6.15.4, Shield Building

ML20323A066
Person / Time
Site:	Watts Bar
Issue date:	11/27/2020
From:	Kimberly Green Plant Licensing Branch II
To:	Tennessee Valley Authority
Green K
References
EPID L-2020-LRM-0090
Download: ML20323A066 (5)

Text

November 27, 2020 LICENSEE: Tennessee Valley Authority FACILITY: Watts Bar Nuclear Plant, Units 1 and 2

SUMMARY

OF OCTOBER 28, 2020, TELECONFERENCE WITH TENNESSEE VALLEY AUTHORITY REGARDING PLANNED LICENSE AMENDMENT REQUEST FOR TECHNICAL SPECIFICATION SURVEILLANCE REQUIREMENT 3.6.15.4, SHIELD BUILDING (EPID L-2020-LRM-0090)

On October 28, 2020, the U.S. Nuclear Regulatory Commission (NRC) staff conducted a Category 1 public teleconference with representatives of Tennessee Valley Authority (TVA).

The purpose of the call was to discuss TVAs planned non-voluntary license amendment request (LAR) to revise Watts Bar Nuclear Plant (Watts Bar), Units 1 and 2, Technical Specification (TS) Surveillance Requirement (SR) 3.6.15.4, Shield Building.

The meeting notice and agenda, dated October 2, 2020, are available at Agencywide Documents Access and Management System (ADAMS) Accession No. ML20295A538. TVAs presentation slides for the meeting are available at ADAMS Accession No. ML20302A123. A list of participants is enclosed.

TVA began its presentation by explaining that an LAR is needed to resolve a non-conservatism in TS SR 3.6.15.4, which currently has the potential to allow more shield building inleakage than analyzed in the safety analysis. The proposed LAR will also align SR 3.6.15.4 with NUREG-1431, Revision 4.0, Standard Technical Specifications - Westinghouse Plants (STS).

TVA stated that its current plant operations are administratively controlled as described in NRC Administrative Letter (AL) 98-10, Dispositioning of Technical Specifications That Are Insufficient to Assure Plant Safety; therefore, in accordance with AL 98-10, an LAR is required to resolve the non-conservative TS.

TVA reviewed the licensing history of SR 3.6.15.4, which was initially based on the emergency gas treatment system (EGTS) TS 3.6.5.5 when TVA issued the proposed TS for Watts Bar, Unit 1. TVA subsequently revised and updated the draft TS to be in accordance with the latest draft of NUREG-1431, Revision 0, and the EGST SR 3.6.5.5 was renumbered as SR 3.6.9.4 and stated, Verify each EGTS train produces an annulus pressure equal to or more negative than -0.5 inch water gauge with respect to the El. 772 mechanical equipment-room with an inleakage of < 250 cfm [cubic feet per minute] at a system flow of 4000 + 10% cfm.

When NUREG-1431, Revision 0, was published, new TS 3.6.19, Shield Building, was included. The new SR 3.6.19.4 required that each shield building air cleanup system train with final flow ~ [ X ] cfm produce a pressure equal to or more negative than [-0.5] inch water gauge in the annulus within [22] seconds after a start signal.

The NRC then transmitted a proof and review version of the Watts Bar, Unit 1, TS for TVAs review and comment. In that version, SR 3.6.9.4 for the EGTS was revised to state, Verify each EGTS train flow rate is 3600 and 4400 cfm, and SR 3.6.15.4 was created and stated, Verify each Emergency Gas Treatment System train with final flow 3600 and 4400 cfm produces an annulus pressure equal to or more negative than -0.5 inch water gauge with respect to EL. 772 mechanical equipment room and with an inleakage of 250 cfm within [TDB]

seconds after a start signal.

When the Watts Bar, Unit 1, operating license was issued, the time requirement in SR 3.6.16.4 was moved to SR 3.6.9.4, and SR 3.6.15.4 was reworded to its current verbiage, Verify each Emergency Gas Treatment System train with final flow 3600 and 4400 cfm produces an annulus pressure equal to or more negative than -0.61 inch water gauge at elevation 783 with respect to the atmosphere and with an inleakage of 250 cfm. The Watts Bar, Unit 2, TS mirrors the Watts Bar, Unit 1, TS.

TVA described the planned changes to SR 3.6.15.4, namely, changing the value for annulus pressure from -0.61 inch water gauge to -0.63 inch water gauge, removal of the inleakage value of 250 cfm, and the addition of a time requirement of 20 seconds from initiation after a start signal. The primary reasons for the changes are that an error was discovered in the calculation of the pressure value, and SR 3.6.15.4 will be aligned with STS SR 3.6.8.4.

The NRC staff noted that the proposed change to add a time requirement to SR 3.6.15.4 includes the phrase from the initiation; however, STS SR 3.6.8.4 does not contain this phrase.

Additionally, the NRC staff pointed out that the proposed wording in SR 3.6.15.4 is slightly different than the existing wording in current SR 3.6.9.4 and that TVA may want to consider changing the proposed language in SR 3.6.15.4 for consistency with SR 3.6.9.4. TVA stated that it would consider the NRC staffs statements and address the issues within the LAR.

The NRC staff asked some clarification questions. With regard to the removal of the inleakage flow requirement in SR 3.6.15.4, the NRC staff asked how TVA maintains the accident safety analysis for this flow requirement. TVA responded that it still plans to retain the 250 cfm inleakage flow requirement in the design output documents and the surveillance instructions for SR 3.6.15.4, and will explain this in the LAR. The NRC staff also asked if TVA is planning to revise SR 3.6.9.4, specifically, to remove the time requirement. TVA replied that it is not revising SR 3.6.9.4 because that would make the LAR voluntary.

The NRC staff pointed out that draft Regulatory Guide DG-1351, Dispositioning of Technical Specifications that Are Insufficient to Ensure Plant Safety, dated June 2018 (ADAMS Accession No. ML18086A690), will replace AL 98-10. TVA stated that it will keep track of this draft guide in the event that it is issued prior to submission of the LAR.

TVA plans to submit the LAR to the NRC in January 2021.

No comments or public meeting feedback were received. No regulatory decisions were made at this meeting.

Please direct any inquiries to me at 301-415-1627 or by e-mail to Kimberly.Green@nrc.gov.

/RA/

Kimberly J. Green, Senior Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-390 and 50-391

Enclosure:

List of Participants cc: Listserv

LIST OF PARTICIPANTS OCTOBER 28, 2020, TELECONFERENCE WITH TENNESSEE VALLEY AUTHORITY REGARDING WATTS BAR NUCLEAR PLANT, UNITS 1 AND 2 PLANNED LICENSE AMENDMENT REQUEST TO REVISE TECHNICAL SPECIFICATION SURVEILLANCE REQUIREMENT 3.6.15.4 Name Organization Kim Green U.S. Nuclear Regulatory Commission (NRC)

Steve Smith NRC Mark Blumberg NRC Brian Lee NRC Angelo Stubbs NRC Clint Ashley NRC David Garmon-Candelaria NRC Vic Cusumano NRC Brian Wittick NRC Russ Wells Tennessee Valley Authority (TVA)

Gordon Williams TVA Doug Pollock TVA Chris Kerlin TVA Enclosure

ML20323A066 *by e-mail OFFICE NRR/DORL/LPL2-2/PM* NRR/DORL/LPL2-2/LA* NRR/DORL/LPL2-2/BC*

NAME KGreen BAbeywickrama (LRonewicz for) UShoop DATE 11/20/2020 11/20/2020 11/25/2020 OFFICE NRR/DORL/LPL2-2/PM*

NAME KGreen DATE 11/27/2020