ML020730229
| ML020730229 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 02/28/2002 |
| From: | Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TAC MB3631 | |
| Download: ML020730229 (14) | |
Text
Tennessee Valley Authority Browns Ferry Nuclear Plant Alternative Source Term Implementation TVA/NRC Meeting Nuclear Reactor Regulation - Rockville MD January 16, 2002
Agenda
" Introduction/Meeting Objectives
" Schedule
" Background
" Analysis Approach
" Analysis Attributes
- Submittal Contents
- Summary and Open Discussion Steve Austin 1
Introduction/Meeting Objectives
"* Introduction
" Previous Meeting Extended Power Uprate
" Meeting Objectives
- Discuss the BFN Approach
- Discuss Submittal Content and Depth of Information
- Obtain NRC Concurrence of TVA's Proposed Methodology
- Gain NRC Insights From Other Alternative Source Term Submittals Steve Austin 2
Schedule Ot,1n 2003 2004 2005 200R 2:07 win 2003 2004 2 E-- EL= El El El L May 02 TVA Submittal To NRC SER NRC For AST For AST TVA Submittal To NRC SER NRC For EPU For EPU Unit-2 Outage Sprin US2CpI 1 Outage W2C12 Outage EPU Full Tm-'ementation Unit-3 0 Spring Spring U3011 Outage U3C10 Outage EPU Full Implementation Steve Austin 3
Background LLL
- BFN Design Features
- BWR-4
- Mark I Containment
- Inerted Primary Containment
- Secondary Containment Common to Units 1, 2, and 3
- Three Trains of Standby Gas Treatment
- 600 Foot Stack
- Units 1,2, and 3 Control Rooms Have a Common Control Room Emergency Ventilation (CREV) System
- 2000 NRC Safety Evaluation For Increased Main Steam Isolation Valve Leakage
- Implemented Main Steam Ruggedness
- Completed Implementation March 2001 Henry Jones 4
Background (Cont.)
~ Current Radiological Analysis Approach
- ORIGEN - Source Terms
- Traditional Regulatory Methods
- Atmospheric Dispersion Coefficients
"* Used in MSIV Increased Leakage Submittal and Associated NRC SER
"* UFSAR Amendment 19
"*Use Existing Values For AST
- ECCS Leakage Henry Jones 5
Analysis Approach
- Requirements of 10 CFR 50.67, Revised Accident Source Term
- Follow Reg Guide 1.183, "Alternative Radiological Source Terms for Evaluating Design Basis Accidents As Nuclear Power Reactors"
- Full Implementation
- Reran ORIGEN Source Term at EPU Conditions
- Suppression Pool Water pH Control
- Filtration Efficiencies
- No Plant Modifications Anticipated Henry Jones 6
Analysis Attributes
- Based on Design Basis Accidents
- Loss of Coolant Accident
- Main Steam Line Break
- Control Rod Drop Accident
- Fuel Handling Accident
- NUREG - 0737 - Mission Doses
- Expressed in Terms of Times and Rates of Appearance of Radioactive Fission Products Released Into Containment
- Types and Quantities of the Radioactive Species Released
- Chemical Forms of Iodine Released Henry Jones 7
Drywell Sprays LLI
" Safety Related Redundant Mode of RHR
" Credit for Drywell Sprays (Loss of Coolant Accident)
- Boiling Water Reactor Sprays Already Credited for AST
"° Perry
"*Grand Gulf
- Manual Actuation
- Drywell Congestion
- Reduced Spray Being Credited for BFN
- Reduced Fall Height Being Credited for BFN
- Standard Review Plan 6.5.2 Used for Spray Removal Rate Henry Jones 8
Main Steam Line Break (MSLB) X/Q Outside Containment
- Current Analysis Approach
- Turbine Building Remains Intact
"* No Credit for Deposition
"* ARCON96 Steady-State Plume X/Q
"* Release Over 2 Hour Time Period
"* Release Through Unit 1 Turbine Building Exhaust (Highest X/Q)
"* Includes Consideration for Dual CREV Intake Henry Jones 9
Main Steam Line Break X/Q (Cont.) UT Outside Containment
- Puff Release Directly to Environment
- Puff X/Q Used
- Immediate Release Assumed
- No Credit for Deposition
° Rising Puff Credited e NRC Puff Model in Draft Regulatory Guide 1111, "Atmospheric Relative Concentrations for Control Radiological Habitability Assessments at Nuclear Power Plants" Will be Considered Henry Jones 10
Use of AEB-98-03 U&
Use of AEB-98-03 Approach With DW Spray Credit and Multiple Steam Line/Condenser Volumes in Series
- TVA Plans to Use AEB-98-03 but With DW Sprays and Multiple Steam Line/Condenser Control Volumes in Series
- DW Sprays Remove Large, Dense Particles
- Multiple Steam Line/Condenser Volumes in Series Decreases the Sedimentation Velocity Distribution in Downstream Control Volumes Henry Jones 11
Submittal Contents !L
- Previous Submittals
- Duane Arnold
- Columbia
- Describe Changes
- Identify the Computer Codes Utilized
- Identify Inputs and Assumptions
- Describe the AST Results
- Identify Affected UFSAR Sections Henry Jones 12
Summary and Open Discussion
"* Evaluations and Acceptance Criteria Will be Consistent With Those Required by 10 CFR 50.67 and Reg Guide 1.183
"* Evaluate Design Bases Accidents
- Acceptable Radiological Analysis Methods and Assumptions
"* Update the Design/Licensing Bases for BFN
- Technical Specifications
- FSAR
- Calculations
" Open Discussion Steve Austin 13