ML25027A018
| ML25027A018 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 01/26/2025 |
| From: | Energy Northwest |
| To: | Division of Operating Reactor Licensing |
| Chawla M, NRR/DORL/LPL4 | |
| References | |
| EPID L-2025-LRM-0006 | |
| Download: ML25027A018 (1) | |
Text
POWERFUL SOLUTIONS Columbia Generating Station License Amendment Request NRC Pre-Submittal Meeting
Agenda Introductions and Opening Remarks License Amendment Request Overview Regulatory Requirements and Guidance LAR Technical Details Closing Remarks/Schedule 2
Introductions and Opening Remarks
Introductions
Nuclear Regulatory Commission Energy Northwest Opening Remarks Purpose of Pre-Submittal Meeting 3
License Amendment Request Overview Approval of revision to Required Action in TS 3.3.2.1, Control Rod Block Instrumentation, is requested This revision eliminates a restriction on the number of reactor startups with an inoperable Rod Worth Minimizer while continuing to minimize accident consequences Reason for request 4
Regulatory Requirements and Guidance 10 CFR 50.36, Technical Specifications 10 CFR 50, Appendix A, General Design Criteria
Criterion 13, Instrumentation and Controls
Criterion 20, Protection System Functions
Criterion 26, Reactivity Control System Redundancy and Capability
Criterion 28, Reactivity Limits NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition 5
LAR Technical Details - BPWS & RWM Banked Position Withdrawal Sequence Applicable for operation between all-rods-in and 10%
power Limits consequences of control rod drop accident during startup/shutdown Rod Worth Minimizer
- Enforces BPWS at low power levels
- Provides backup to operator control of rod sequences
- Ensures initial conditions of control rod drop accident are not violated
- Can apply rod blocks but no direct plant control 6
LAR Technical Details - TS 3.3.2.1 History of TS 3.3.2.1 RWM vs. RCSC ISTS Conversion GE Analysis 7
Current Actions Suspend rod movement Verify >12 rods withdrawn and verify rod movement with additional staff Verify startup with inop RWM not performed recently and verify rod movement with additional staff
LAR Technical Details - Accident Analysis Rod Drop Accident
- Design basis reactivity insertion event
- Maximum reactivity worth rod falling from full insertion to full withdrawal
- Can create localized fuel melting prior to automatic systems initiating a SCRAM
- Estimated probability of 10-12 per reactor year and requires a series of failures/errors
- Consequences not directly reliant on RWM Rod Withdrawal Error 8
LAR Technical Details - Safety Low Accident Probability Engineered Safety Feature Defense-in-Depth Safety During Startup 9
License Amendment Request Overview 10 ProposedTS3.3.2.1 CurrentTS3.3.2.1 CompliancewithBPWSrequiredper TS3.1.6,RodPatternControl CompliancewithBPWSrequiredper TS3.1.6,RodPatternControl ControlrodsmovedbylicensedOperator inaccordancewithpreestablishedrod withdrawalsequences ControlrodsmovedbylicensedOperator inaccordancewithpreestablishedrod withdrawalsequences 2ndlicensedOperatororqualified memberofthetechnicalstaffenforces adherencetoBPWS androdcouplings checkedifRWMinoperableand<12rods withdrawn 2ndlicensedOperatororqualified memberofthetechnicalstaffenforces adherencetoBPWSifRWMinoperable and>12rodswithdrawn ReactorstartupwithinoperableRWMnot restricted ReactorstartupwithinoperableRWM restrictedtooncepercalendaryear
License Amendment Request Overview Current TS Proposed TS 11
Closing Remarks Columbia LAR follows similar precedence Oyster Creek, ML011160423 FitzPatrick, ML24313A147 Additional action to perform coupling checks ensure the equipment is working as intended to preclude an accident All other provisions of TS 3.3.2.1 will remain 12
Current Schedule Submittal end of March 2025 Audit/RAI dates after July 2025 are preferable due to an extended refueling outage Approval requested within 12 months 13
POWERFUL SOLUTIONS QUESTIONS?