ML18248A107

Presentation Slides - Watts Bar Nuclear Plant Units 1 and 2 Adoption of 10 CFR 50.69 - September 6, 2018

ML18248A107
Person / Time
Site:	Watts Bar
Issue date:	09/05/2018
From:	James Shea, Skaggs M Tennessee Valley Authority
To:	Division of Operating Reactor Licensing
Jordan N
References
Download: ML18248A107 (16)

Text

Watts Bar Nuclear Plant Units 1 and 2 Adoption of 10 CFR 50.69 September 6, 2018

Agenda

• 10 CFR 50.69 Background

• License Amendment Background

• Operating Experience

• Watts Bar 50.69 Evaluation Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 2

10 CFR 50.69 Overview High Safety Reduce Significant Burden Areas It has the potential to provide the industry substantial cost savings Low Safety and drive the goals of Significant Increase Areas Focus the Delivering the Nuclear Promise Initiative From NEI Risk Informed Engineering Programs Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 3

Overview - Categorization Safety Related Low Risk 50.69 High Risk Non Safety Related From NEI Risk Informed Engineering Programs Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 4

Overview - Exempted Special Treatment Requirements From NEI Risk Informed Engineering Programs Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 5

License Amendment Background

• Delivering the Nuclear Promise Efficiency Bulletins (EB)

EB 17-09 LAR Submittal LAR Template EB 17-16 Process Implementation

• LAR Coordinating Committee Peer review prior to submittal Comments resolved prior to submittal Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 6

License Amendment Background - cont.

• Joint Owners Group Committee Collaboration Sharing Infrastructure Training Information Sharing Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 7

HSS Component Determination Overview Determination of High Safety Significant (HSS)

Components for Indicated Events/Hazards

- Internal Events, Risk Imp. Measures & Sensitivity Studies

- Internal Flooding, Risk Imp. Measures & Sensitivity Studies

- Seismic Events, Risk Imp. Measures & Sensitivity Studies

- Internal Fire, Fire Protection Program Safe Shutdown Equipment List (SSEL)

- Other External Hazards, any System, Structure or Component (SSC) Credited by the IPEEE to Screen the Hazard

- Shutdown Risks, Safety Function Defense-In Depth Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 8

PRA Technical Adequacy Evaluation Internal Events & Internal Flooding PRA Model

- Peer reviewed in accordance with RG 1.200 Rev. 2 and ASME/ANS PRA Standard (2008) Addendum a

- Underwent Fact and Observation (F&O) Closure Process

- Seven Open F&Os (Finding Level) which were assessed against the 50.69 application Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 9

PRA Technical Adequacy Evaluation cont.

Seismic PRA Model

- Full Scope Peer Review against the 2008 ASME/ANS PRA Standard Addendum b Part 5 (seismic)

- Underwent F&O Closure Process

- One Open F&O (Finding Level) which was assessed against the 50.69 Application Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 10

Model Update and Maintenance TVA procedures ensure or provide:

- Model configuration, fidelity and realism

- Periodic update requirements

- Living model requirements

- PRA model updates

> PRA Maintenance

> PRA Upgrade

- Peer Review requirements Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 11

Non-Modeled Hazards Internal Fire Hazards

- Deviation from the NEI 00-04 approach.

- The Watts Bar 50.69 process will use the Fire Protection Program Safe-Shutdown Equipment List (SSEL)

Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 12

Non-Modeled Hazards cont.

• Other External Hazards - the WBN process will use the screening results from the IPEEE for evaluation of safety significance related to:

- High Winds

- External Flooding

- Transportation and Nearby Facility Accidents

- Other External Initiating Events

• All SSCs credited in IPEEE Other External Hazards evaluation to allow the hazard to screen will be considered High Safety Significant (HSS)

• Other External Hazard screening was reviewed against the current as-built, as-operated plant Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 13

Low-Power / Shutdown

• The WBN Categorization process will use the shutdown safety management plan described in NUMARC 91-06, for evaluation of safety significance related to low power and shutdown conditions.

• TVA process assesses the potential impact on shutdown risk o Focus on planning, conservative decision-making and maintaining defense-in-depth o Assessment of plant shutdown configurations for impact on Key Safety Functions Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 14

LAR Schedule

• Week of 9/10/18-Draft 50.69 LAR to be reviewed by Industry Coordinating Committee

• Coordination with TSTF-425 Submittal

- It is expected that there will be review efficiencies gained because of the common PRA usage

- Both the 10 CFR 50.69 LAR and TSTF-425 LAR submittals are planned for 9/28/18

• A one-year NRC review is requested

• Upon approval, the 50.69 License Amendment will be implemented within 60 days Watts Bar 10 CFR 50.69 LAR Pre-Submittal Meeting With NRC l 15