ML12264A320
| ML12264A320 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 10/11/2012 |
| From: | Taplett K South Texas |
| To: | Balwant Singal Plant Licensing Branch IV |
| Singal B | |
| References | |
| TAC ME9182, TAC ME9183 | |
| Download: ML12264A320 (14) | |
Text
Pre-licensing Meeting for License Amendment Request to Revise Amendment Request to Revise the Fire Protection Program at the South Texas Project October 11, 2012 October 11, 2012 1
Agenda Agenda
- Introductions
- Purpose B
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- Background
- Fire Protection Program Change
- Bases of Change
- Bases of Change
- Additional Information to be Developed
- Summary
- Questions 2
South Texas Project (STP) Representatives South Texas Project (STP) Representatives
- Mike Murray - Manager, Regulatory Affairs
- Ken Taplett - Licensing Engineer Ken Taplett Licensing Engineer
- Frank Cox - Fire Safe Shutdown Engineer
- Charles Albury - Thermal-Hydraulic Analysis Supervisor y
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- Donald Rohan - Operations Procedure Writer Responsible for plant off-normal procedures in response to fire Previously licensed as a Senior Reactor Operator 3
Previously licensed as a Senior Reactor Operator
Purpose Purpose Describe the STP Nuclear Operating Company proposal p
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to revise the South Texas Project, Units 1 and 2, Fire Protection Program 4
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Background===
Background
- The change involves revising the STP Licensing Basis f
ti th lt ti h td bilit for meeting the alternative shutdown capability.
- STP is required by their licensing basis to meet the i
t f 10 CFR 50 A di R S ti III L requirements of 10 CFR 50, Appendix R, Section III.L, Alternative and dedicated shutdown capability.
STP is currently relying on compensatory measures to
- STP is currently relying on compensatory measures to meet their licensing basis.
- STP recently withdrew a license amendment request
- STP recently withdrew a license amendment request because insufficient information was provided to the NRC staff to approve the amendment request.
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Fire Protection Program Change Fire Protection Program Change
- In order to meet the regulatory requirements of Appendix R,Section III.L, the proposed amendment request:
- Credits the performance of operator actions in the control room, in addition to tripping the reactor, prior to evacuation due to a fire fire.
- Credit the automatic trip of the main turbine in response to a reactor trip reactor trip.
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Bases of Change Bases of Change Regulatory Guide 1.189, Fire Protection for Nuclear Power Plants, usually credits a reactor trip prior to control room evacuation usually credits a reactor trip prior to control room evacuation.
In order to credit additional control room actions:
Th li t d t
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- The licensee must demonstrate the actions can be performed
- The licensee should ensure that such actions cannot be negated by subsequent spurious actuation signals resulting from the postulated fire.
- The licensee should consider one spurious actuation to occur before t
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t i hi d th h th lt ti d di t d control of the plant is achieved through the alternative or dedicated shutdown system.
Both (1) the loss of offsite power and (2) maintaining offsite power
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scenarios should be considered.
Automatic functions of circuits in the control room fire should not be credited if the function would mitigate the consequences 7
credited if the function would mitigate the consequences.
Bases for Change (continued)
Bases for Change (continued)
- The feasibility and reliability of the additional operator actions have been demonstrated.
- A single spurious actuation analysis demonstrates that no single spurious actuation could negate a control room action in manner that Appendix R,Section III.L action in manner that Appendix R,Section III.L requirements are not met.
- The automatic turbine trip analysis provides reasonable
- The automatic turbine trip analysis provides reasonable assurance that the turbine will trip when actuated by a reactor trip and would not subsequently be negated by a fire induce circuit failure 8
fire-induce circuit failure.
Bases for Change (continued)
Bases for Change (continued)
- Defense-in-Depth Analysis addresses the p
y following:
- Fire Prevention Measures Fire Prevention Measures
- Capability to detect, control and extinguish fires
- Protection of structures, systems and components so that fires will not prevent safe shutdown that fires will not prevent safe shutdown
- Safety margin analyses
- Analysis for those actions with small time margins shows the plant can achieve safe shutdown conditions when plant can achieve safe shutdown conditions when considering instrument uncertainties.
- Analysis to justify plant safe shutdown is achievable in event all the requested actions are not completed.
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Additional Information t
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to be Developed Address the following scenario:
- Spurious actuation of pressurizer power-operated relief valve p
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p (PORV), and
- Pressurizer PORV block valve cannot be closed due to fire-induced circuit failure, and
- No actions credited in the control room other than manual reactor trip and automatic turbine trip, and
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Additional Information t
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to be Developed
- Scenario will address the following:
- Ability to maintain and/or restore natural circulation
- Impact on sub-cooling margin I
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- Impact on fuel integrity 11
Addi i l I f i
Additional Information to be Developed Add th i
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- Address the impact on reactor vessel water level for a spuriously opened steam generator PORV.
- Address the impact of a control room fire on the initiation of safety injection.
initiation of safety injection.
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Summary Summary
- License Amendment Request will be resubmitted Request approval of same operator actions and automatic
- Request approval of same operator actions and automatic turbine trip as the previously withdrawn request.
- Bases for approval are the actions can be performed and that the actions cannot be negated by subsequent spurious actuation signals resulting from the postulated fire.
- Automatic turbine trip relies on success of reactor trip.
- Sufficient defense-in-depth/safety margin exists to demonstrate safe shutdown conditions can be achieved based on analyses previously performed and additional information to be developed.
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Questions?
Questions?
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