ML19298A955

License Amendment Request for a Revision to the Dose Consequence Analysis for a Loss of Coolant Accident - Pre-Application Meeting, October 29, 2019

ML19298A955
Person / Time
Site:	Susquehanna
Issue date:	10/29/2019
From:	Sujata Goetz Plant Licensing Branch 1
To:	Cimorelli K Susquehanna
Goetz S
References
Download: ML19298A955 (8)

Text

Susquehanna Steam Electric Station Pre-Application Meeting October 29, 2019 License Amendment Request for a Revision to the Dose Consequence Analysis for a Loss of Coolant Accident

Meeting Purpose

• Describe a future license amendment request

• Establish a common understanding of the scope of the request

• Establish a common understanding of the schedule

• Obtain NRC feedback

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Proposed Changes to Analysis

• Upgrade to ORIGEN-ARP for source term

• Reduce assumed ESF leakage to align with RG 1.183

• Increase assumed Secondary Containment inleakage

• Increase assumed CRHE inleakage

• Eliminate CRHE continuous occupancy areas to align with RG 1.183

• Upgrade to RADTRAD Version 3.10

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Impacted Parameters Parameter Existing DBA LOCA AOR RB Inleakage 140%/day (4041.1 cfm)

SGTS Flow Rate 11,110 cfm (first 10 minutes) and 4041.1 cfm thereafter ESF Leakage into RB 20 gpm (2.674 cfm)

CRHE Unfiltered Air Inleakage 500 cfm Continuous occupancy locations Elevation 741-1 (all)

Elevation 729 (all)

Elevation 698 (Computer Room)

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Continuous Occupancy Assumptions Current Assumptions

• Elevation 741-1

- All Areas

• Elevation 729

- All Areas

• Elevation 698

- Computer Room Only Revised Assumptions

• Elevation 741-1

- Technical Support Center Only

• Elevation 729

- Control Room Only

• Elevation 698

- Computer Room Only

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Aggregate Dose Impacts Post-LOCA Dose Type Existing DBA LOCA AOR (Rem TEDE)

Regulatory Limit (Rem TEDE)

Control Room (30 Day) 4.69 5

EAB (Worst Case 2 Hour) 12.0 25 LPZ (30 Day) 4.53 25

• Control room dose will decrease

• EAB dose will increase

- Remains below regulatory limit

• LPZ dose will decrease

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Summary

• Change in method

• Multiple changes to assumptions/inputs

• Post-LOCA doses remain within 10 CFR 50.67 limits

• Minor impacts to TS and TS Bases

• Required to support fuel loading in spring 2021

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List of Acronyms AOR - Analysis of Record CR - Control Room CRHE - Control Room Habitability Envelope DBA - Design Basis Accident EAB - Exclusion Area Boundary ESF - Emergency Safety Feature LOCA - Loss of Coolant Accident LPZ - Low Population Zone MSIV - Main Steam Isolation Valve RB - Reactor Building RG - Regulatory Guide SGTS - Standby Gas Treatment System TEDE - Total Effective Dose Equivalent TS - Technical Specifications

© Talen Energy 8