ML19263A643

NRR E-mail Capture - RAI - Vogtle End State License Amendment Request (LAR) to Revise the Technical Specifications (Tss) for Vogtle, Units 1 and 2 (L-2019-LLA-0148)

ML19263A643
Person / Time
Site:	Vogtle
Issue date:	09/19/2019
From:	John Lamb Plant Licensing Branch II
To:	Lowery K Southern Nuclear Operating Co
References
L-2019-LLA-0148
Download: ML19263A643 (3)

Text

NRR-DRMAPEm Resource From: Lamb, John Sent: Thursday, September 19, 2019 1:36 PM To: Lowery, Ken G.; Joyce, Ryan M.

Subject:

RAI - Vogtle End State LAR (L-2019-LLA-0148)

Importance: High Mr. Lowery:

By application dated July 9, 2019 (Agencywide Documents Access and Management System (ADAMS)

Accession No. ML19190A309), Southern Nuclear Operating Company (SNC, the licensee) submitted a license amendment request (LAR) to revise the Technical Specifications (TSs) for Vogtle Electric Generating Plant (VEGP), Units 1 and 2.

The proposed changes would revise the actions of TS 3.7.7, Component Cooling Water (CCW) System, TS 3.7.8, Nuclear Service Cooling Water (NSCW) System, TS 3.8.1, AC Sources- Operating, TS 3.8.4, DC Sources- Operating, TS 3.8.7, Inverters- Operating, and TS 3.8.9, Distribution Systems - Operating.

The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed your application and has determined that additional information is needed to complete its review. The NRC staff has developed the below DRAFT request for additional information (RAI) in support of its review of the subject LAR.

The NRC staff had a clarifying call on September 19, 2019, to ensure the RAI questions are understandable, the regulatory basis for the questions is clear, and to determine if the information requested was previously docketed. The SNC staff stated that SNC would provide a response to the RAI within 30 days of this email.

If you have questions, you can contact me at 301-415-3100.

Sincerely, John G. Lamb, Senior Project Manager REQUEST FOR ADDITIONAL INFORMATION Southern Nuclear Operating Company (SNC, the licensee) proposed to add new Condition D to both Technical Specification (TS) 3.7.7, Component Cooling Water (CCW) System and TS 3.7.8, Nuclear Service Cooling Water (NSCW) System. Condition D would be entered within one hour after both CCW (or NSCW) trains are inoperable and probabilistic risks assessment (PRA) non-functional, or within the risk-informed completion time (RICT) if at least one train is PRA functional while both trains are TS inoperable. In the event both CCW (or NSCW) trains are declared TS inoperable and PRA nonfunctional, Condition D would direct the plant to be attain MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> without the required support systems [i.e., CCW (or NSCW)] available to support this plant progression.

As stated in Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 36(c)(2)(i), when a limiting condition for operations (LCO) of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TS until the LCO can be met. The intent of this requirement is to place the plant in a safe and attainable state until the LCO supporting continued normal operation is satisfied.

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Improved Standard Technical Specifications (ISTS) of NUREG-1431 for TS 3.7.7 and TS 3.7.8 provide no direction with respect to two inoperable trains of CCW or SWS. Thus, the provisions of TS 3.0.3 would apply for two inoperable trains of CCW or SWS, which specifies a shutdown and cooldown to cold shutdown conditions. However, the Bases of VEGP TS 3.0.3 state that exceptions are provided to the actions of LCO 3.0.3 where requiring a unit shutdown/cooldown would not provide appropriate remedial measures.

TSTF-432, Revision 1 Change in Technical Specifications End States (WCAP-16294) Section 1.0 Description reads in part:

The risk of the transition from MODE 1 to MODE 4 or MODE 5 depends on the equipment that is operable. For example, the transition from MODE 4 to MODE 5 can introduce additional risk since it is required to realign the unit from steam generator cooling to residual heat removal, or shutdown cooling. During this realignment, there is an increased potential for loss of shutdown cooling and loss of inventory events, which is reflected in the plant risk calculated using Probabilistic Risk Assessment (PRA). In addition, decay heat removal following a loss of offsite power event in MODE 5 is dependent on Emergency [alternating current] AC power, whereas, in MODE 4, the turbine-driven auxiliary feedwater pump is available without relying on Emergency AC power. Therefore, transitioning to MODE 5 may not always be the appropriate end state from a risk perspective.

The NRC staff recognizes that the above conclusion was intended to apply where only one of two trains was not restored to operable status with the completion time. However, the assessment is valid in other conditions where equipment essential to support maintenance of a cold shutdown condition is not suitably reliable.

Given that Condition D of proposed TS 3.7.7, and TS 3.7.8 specify a cold shutdown end state that might be unattainable given the entry condition, either provide justification that reliable equipment would be available to reach that end state or propose an alternate end state, consistent with the intent of 10 CFR 50.36(c)(2)(i) and the Bases of VEGP TS 3.0.3. If attaining the specified end state requires use of equipment in a manner different than that described in the safety analysis report, provide appropriate additional descriptions of the equipment and manner of use.

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Hearing Identifier: NRR_DRMA Email Number: 212 Mail Envelope Properties (SN6PR0901MB239990918507E7268567A665FA890)

Subject:

RAI - Vogtle End State LAR (L-2019-LLA-0148)

Sent Date: 9/19/2019 1:36:14 PM Received Date: 9/19/2019 1:36:00 PM From: Lamb, John Created By: John.Lamb@nrc.gov Recipients:

"Lowery, Ken G." <KGLOWERY@southernco.com>

Tracking Status: None "Joyce, Ryan M." <RMJOYCE@southernco.com>

Tracking Status: None Post Office: SN6PR0901MB2399.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 5064 9/19/2019 1:36:00 PM Options Priority: High Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received: