ML060250038
| ML060250038 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 11/07/2005 |
| From: | Duke Energy Corp |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML060240605 | List: |
| References | |
| Download: ML060250038 (28) | |
Text
1 Duke Power Appendix R Reconstitution Oconee (ONS)
November 07, 2005 ATTACHMENT 5
2 Purpose
Present General Overview of Reconstitution Methodology
Show how Reconstitution Data/Information is used as a direct input into the Fire PRA
Discuss How Recent Staff Positions May Impact NFPA-805 Transition
3
Split into Three Phases:
Phase I - Safe Shutdown Equipment List (SSEL) and Logic Diagrams
Phase II - Cable and Fire Area Analysis -
identifies all cable/component hits
Phase III - Performance Based/Risk Informed analysis of multiple spurious actuations in accordance with NFPA-805 Appendix R Reconstitution Safe Shutdown Methodology
4
Phase I
Define Safe Shutdown Functions, Systems and Components
Safe Shutdown components listed in a Safe Shutdown Equipment List (SSEL)
System and Component Dependencies are documented on System and Component Logic Diagrams Appendix R Reconstitution Safe Shutdown Methodology -
continued
5 DUKE POWER COMPANY OCONEE NUCLEAR STATION UNITS 1, 2, & 3 APPENDIX R SAFE SHUTDOWN SYSTEM LOGIC DIAGRAM SHEET 1 OF 1 DWG. NO. APPENDIX R - LOGIC - U0 - SLD - 001 PREPARED BY CHECKED BY APPROVED BY DATE DATE DATE REV.
QA CONDITION 1 REVIEWED BY DISCIPLINE Reactor Reactivity Control Decay Heat Removal Fire Occurs in Any Fire Area Normal Plant Operating at Power Reactor Pressure and Inventory Control Mechanical Support Functions Service Water Systems (LPS/HPS)
Component Cooling System (CC)
HVAC (VS)
Chemical & Volume Control Systems (HPI/LPI/CF)
Residual Heat Removal System (LPI)
Reactor Pressure Control Reactor Coolant Inventory Control Reactor Trip System Reactor Coolant System (RC)
Main Steam Systems (MS/SD)
Emergency Feedwater Systems (FDW/C/CCW)
Chemical & Volume Control Systems (HPI/LPI/SF)
Process Monitoring Reactor Coolant System Instrumentation (RC)
Diagnostic Indicators Safe Shutdown Tank Level Indicators (C/LPI)
Steam Generator Level and Pressure (FDW/MS) 0 Residual Heat Removal System (LPI)
Chemical & Volume Control Systems (HPI/LPI/SF)
Condenser Circulating Water System (CCW)
Support Functions Keowee Emergency Power (ELK) 230KV Switchyard &
125VDC System (SYD) 4160/600/208VAC Auxiliary Power (EL)
Electrical Support Functions 100KV Auxiliary Power (EL)
SSF 125VDC/120VAC Power (EL)
SSF 4160/600/120VAC Power (EL)
SSF Diesel Generator 250VDC Power &
125VDC/120VAC Vital Power (EL)
Keowee Underground Path (ELK)
Note 1
- 1. Two paths are credited for Chemical and Volume Control: a) High Pressure Injection Pumps supplied from the BWST (LPI System) with normal Letdown available, or b) SSF RC Makeup Pump (HPI System) supplied from the Spent Fuel Pool (SF System) with Letdown back to the Spent Fuel Pool.
NOTES
- 2. Four paths are credited for Emergency Feedwater: a) Turbine Driven EFW Pump supplied from either the hotwell or the Upper Surge Tanks b) Motor Driven EFW Pumps supplied from either the hotwell or the Upper Surge Tanks, c) ASW pump supplied from the CCW System, and d) the SSF Auxiliary Service Water Pump supplied from the CCW System.
Note 1 Note 1 Note 2
- 3. Note Deleted
- 4. The SSF diesel generator does not have enough capacity to power all required cold shutdown loads; therefore, the Keowee Underground Path is credited as a power source for an Appendix R fire requiring shutdown from the SSF.
Note 4 1
James L. McGraw 12/20/01 Leonard J. LaCrosse 12/20/01 Joseph G. Redmond 12/20/01 DUKE POWER COMPANY OCONEE NUCLEAR STATION UNITS 1, 2, & 3 APPENDIX R SAFE SHUTDOWN SYSTEM LOGIC DIAGRAM SHEET 1 OF 1 DWG. NO. APPENDIX R - LOGIC - U0 - SLD - 001 PREPARED BY CHECKED BY APPROVED BY DATE DATE DATE REV.
QA CONDITION 1 REVIEWED BY DISCIPLINE DUKE POWER COMPANY OCONEE NUCLEAR STATION UNITS 1, 2, & 3 APPENDIX R SAFE SHUTDOWN SYSTEM LOGIC DIAGRAM SHEET 1 OF 1 DWG. NO. APPENDIX R - LOGIC - U0 - SLD - 001 PREPARED BY CHECKED BY APPROVED BY DATE DATE DATE REV.
QA CONDITION 1 REVIEWED BY DISCIPLINE Reactor Reactivity Control Reactor Reactivity Control Decay Heat Removal Decay Heat Removal Fire Occurs in Any Fire Area Normal Plant Operating at Power Normal Plant Operating at Power Reactor Pressure and Inventory Control Reactor Pressure and Inventory Control Mechanical Support Functions Service Water Systems (LPS/HPS)
Service Water Systems (LPS/HPS)
Component Cooling System (CC)
Component Cooling System (CC)
HVAC (VS)
HVAC (VS)
Chemical & Volume Control Systems (HPI/LPI/CF)
Chemical & Volume Control Systems (HPI/LPI/CF)
Residual Heat Removal System (LPI)
Residual Heat Removal System (LPI)
Reactor Pressure Control Reactor Coolant Inventory Control Reactor Trip System Reactor Trip System Reactor Coolant System (RC)
Main Steam Systems (MS/SD)
Main Steam Systems (MS/SD)
Emergency Feedwater Systems (FDW/C/CCW)
Emergency Feedwater Systems (FDW/C/CCW)
Chemical & Volume Control Systems (HPI/LPI/SF)
Process Monitoring Reactor Coolant System Instrumentation (RC)
Diagnostic Indicators Diagnostic Indicators Safe Shutdown Tank Level Indicators (C/LPI)
Steam Generator Level and Pressure (FDW/MS) 0 Residual Heat Removal System (LPI)
Residual Heat Removal System (LPI)
Chemical & Volume Control Systems (HPI/LPI/SF)
Chemical & Volume Control Systems (HPI/LPI/SF)
Condenser Circulating Water System (CCW)
Condenser Circulating Water System (CCW)
Support Functions Support Functions Support Functions Keowee Emergency Power (ELK)
Keowee Emergency Power (ELK) 230KV Switchyard &
125VDC System (SYD) 230KV Switchyard &
125VDC System (SYD) 4160/600/208VAC Auxiliary Power (EL) 4160/600/208VAC Auxiliary Power (EL)
Electrical Support Functions Electrical Support Functions Electrical Support Functions 100KV Auxiliary Power (EL) 100KV Auxiliary Power (EL)
SSF 125VDC/120VAC Power (EL)
SSF 4160/600/120VAC Power (EL)
SSF Diesel Generator SSF 125VDC/120VAC Power (EL)
SSF 125VDC/120VAC Power (EL)
SSF 4160/600/120VAC Power (EL)
SSF 4160/600/120VAC Power (EL)
SSF Diesel Generator SSF Diesel Generator SSF Diesel Generator 250VDC Power &
125VDC/120VAC Vital Power (EL) 250VDC Power &
125VDC/120VAC Vital Power (EL)
Keowee Underground Path (ELK)
Keowee Underground Path (ELK)
Note 1
- 1. Two paths are credited for Chemical and Volume Control: a) High Pressure Injection Pumps supplied from the BWST (LPI System) with normal Letdown available, or b) SSF RC Makeup Pump (HPI System) supplied from the Spent Fuel Pool (SF System) with Letdown back to the Spent Fuel Pool.
NOTES
- 2. Four paths are credited for Emergency Feedwater: a) Turbine Driven EFW Pump supplied from either the hotwell or the Upper Surge Tanks b) Motor Driven EFW Pumps supplied from either the hotwell or the Upper Surge Tanks, c) ASW pump supplied from the CCW System, and d) the SSF Auxiliary Service Water Pump supplied from the CCW System.
Note 1 Note 1 Note 2
- 3. Note Deleted
- 4. The SSF diesel generator does not have enough capacity to power all required cold shutdown loads; therefore, the Keowee Underground Path is credited as a power source for an Appendix R fire requiring shutdown from the SSF.
Note 4 1
James L. McGraw 12/20/01 Leonard J. LaCrosse 12/20/01 Joseph G. Redmond 12/20/01 Example System Logic Diagram
6 DUKE POWER COMPANY OCONEE NUCLEAR STATION UNIT 1 APPENDIX R SAFE SHUTDOWN COMPONENT LOGIC DIAGRAM HIGH PRESSURE INJECTION SYSTEM (HPI)
SHEET 1 OF 4 DWG. NO. APPENDIX R - LOGIC - U1 - HPI - 001 PREPARED BY CHECKED BY APPROVED BY DATE DATE DATE REV.
0 QA CONDITION 1 REVIEWED BY DISCIPLINE DUKE POWER COMPANY OCONEE NUCLEAR STATION UNIT 1 APPENDIX R SAFE SHUTDOWN COMPONENT LOGIC DIAGRAM HIGH PRESSURE INJECTION SYSTEM (HPI)
SHEET 1 OF 4 DWG. NO. APPENDIX R - LOGIC - U1 - HPI - 001 PREPARED BY CHECKED BY APPROVED BY DATE DATE DATE REV.
0 QA CONDITION 1 REVIEWED BY DISCIPLINE E
1HP VA0024 OPEN NC/FAI E
1HP VA0024 OPEN E
1HP VA0024 OPEN NC/FAI E
1HP VA0025 OPEN NC/FAI E
1HP VA0025 OPEN E
1HP VA0025 OPEN NC/FAI 1HPIPU0001 ON 1HPIPU0001 ON 1HP VA0098 OPEN NO/FAI E
1HP VA0098 OPEN NO/FAI E
1HPIPU0003 ON 1HPIPU0003 ON 1HPIPU0002 ON 1HPIPU0002 ON 1HP VA0115 OPEN NO/FAI E
1HP VA0115 OPEN NO/FAI E
E 1HP VA0026 OPEN NC/FAI E
1HP VA0026 OPEN NC/FAI 1HP VA0116 OPEN NC 1HP VA0116 OPEN NC Seal Injection Flowpath Established 1HP VA0031 OPEN NT/FO 1HP VA0031 OPEN NT/FO 1HP VA0027 OPEN NO/FAI E
1HP VA0027 OPEN NO/FAI E
Demand for HPI System Charging Flowpath Established U1 & U2 SFP AVAILABLE U1 & U2 SFP AVAILABLE 1SF VA0001 OPEN NO 1SF VA0001 OPEN NO E
1SF VA0097 OPEN NC/FAI E
1SF VA0097 OPEN E
1SF VA0097 OPEN NC/FAI E
1SF VA0082 OPEN NC/FAI E
1SF VA0082 OPEN E
1SF VA0082 OPEN NC/FAI 1HPIPU0005 ON 1HPIPU0005 ON E
1HP VA0417 CLOSED NC/FAI E
1HP VA0417 CLOSED E
1HP VA0417 CLOSED NC/FAI E
1HP VA0405 CLOSED NC/FAI E
1HP VA0405 CLOSED E
1HP VA0405 CLOSED NC/FAI E
1HP VA0398 OPEN NC/FAI E
1HP VA0398 OPEN E
1HP VA0398 OPEN NC/FAI BWST Water Available Via LPI System LOGIC-U1-LPI-001 (1)
E 1HP VA0426 OPEN NC/FAI E
1HP VA0426 OPEN E
1HP VA0426 OPEN NC/FAI E
1HP VA0428 OPEN NC/FAI E
1HP VA0428 OPEN E
1HP VA0428 OPEN NC/FAI 1SF VA0002 OPEN NO 1SF VA0002 OPEN NO Letdown Path Established RC Inventory Control Established (Transition to Cold Shutdown)
Note 1 Notes To preclude excess boron dilution during Mode 5, one HPI pump is repaired (if required) to inject to the RCS with the suction aligned to the BWST. If additional letdown is needed, the RCS letdown can be provided back to the SFP for a "feed and bleed" method of increasing boron concentration through the RC Makeup System.
1.
LPS System Supply to HPI Pump/Motor Cooling Jackets LPS System Supply to HPI Pump/Motor Cooling Jackets LOGIC-U1-LPS-002 (1) 1HP VA0472 OPEN NC 1HP VA0472 OPEN NC LOGIC-U1-HPI-002 (1)
Seal Injection & RC Makeup Flowpath Established The instrumentation required to be functional is dependent on the HPI flow paths chosen for hot and cold shutdown.
2.
Aux. Pressurizer Spray to RC System Aux. Pressurizer Spray to RC System LOGIC-U1-RC-001 (1)
LOGIC-U1-RC-001 (1)
Valves 1HP VA0405, 0417, 0426 & 0428 are shown on sheets 1 and 2 of this drawing series. Valves 1HP VA0001, 0002, 0003, & 0004 are shown on sheets 2 and 3 of this drawing series.
3.
Note 3 Note 3 Note 3 Note 3 1HP VA0120 OPEN NT/FO P
1HP VA0120 OPEN NT/FO P
1HP VA0023 OPEN NO/FAI E
1HP VA0023 OPEN NO/FAI E
LOGIC-U1-HPI-003 (1)
SSF Letdown Path Established Instruments 1HPIPT0016 and 1HPIP0029 are currently credited for postulated fires in West Penetration Room, Cable Trench and SSF. Since fires in these areas will not affect instrument air, assuming the power supply to the IA compressors are available, the devices can be credited for postulated fires in these areas. If Pressurizer Level indication is available then 1HPIPT0016 and 1HPIP0029 are not required. If these instruments are required for other fire scenarios, additional analysis will be required.
4.
Note 5 Note 5, 6 Note 5, 6 1HP VA0355 OPEN NC/FC LOGIC-U1-HPI-002 (3)
LOGIC-U1-HPI-002 (3)
LOGIC-U1-HPI-002 (2)
LOGIC-U1-HPI-002 (2)
E 1HP VA0409 OPEN NC/FAI E
1HP VA0409 OPEN NC/FAI E
1HP VA0410 OPEN NC/FAI E
1HP VA0410 OPEN NC/FAI Note 7 1
James L McGraw Leonard J. LaCrosse Joseph G. Redmond 12/20/01 12/20/01 12/20/01 1
James L McGraw Leonard J. LaCrosse Joseph G. Redmond 12/20/01 12/20/01 12/20/01 2
Ronald J. Cichon William M. McDevitt Joseph G. Redmond 12/23/02 12/23/02 12/30/02 2
Ronald J. Cichon William M. McDevitt Joseph G. Redmond 12/23/02 12/23/02 12/30/02 OFF LOGIC-U1-RC-002 (2)
LOGIC-U1-RC-002 (2)
LOGIC-U1-RC-002 (1)
LOGIC-U1-RC-002 (1)
Note 1 1HP VA0140 THROTTLED NC 1HP VA0140 THROTTLED NC 1HP VA0122 THROTTLED NC 1HP VA0122 THROTTLED NC (Notes are continued on sheet 2.)
Note 10 Example Component Logic Diagram - HPI System
7 Example Safe Shutdown Equipment List Page
8
Phase II
Identify cables for each component
Identify routing for each cable
Routing through each Fire Area documented
Fire Area damage assessments performed
Results of damage assessments used with Logic Diagrams to determine impact on Safe Shutdown Functions
Loss of Safe Shutdown Functions addressed through Appendix R Issue Resolution Process for spurious actuations within Design Basis Appendix R Reconstitution Safe Shutdown Methodology -
continued
9 Example Circuit - HPI Pump
10 Example Safe Shutdown Cable Selection Worksheet Page
11 Example Cable Block Diagram
12 Example Cable Routing Worksheet Page
13 Example Simplified Cable Layout Turbine Bldg Main Control Room Cable Room Equipment Room Pump Room Electrical Switchgear Pump DC Control Power Cabinet 3/
Power Cable DC Control Power Main Control Board Control Cables
14 Example Fire Area Compliance Assessment Page
15
Phase III
As Dennis will be explaining in more detail, results of Phase II are combined with an extensive Multiple Spurious Review to address completeness of multiple spurious population
Deterministic Analysis Output (Phase II)
PRA Cut Set Review
Expert Panel Review Appendix R Reconstitution Safe Shutdown Methodology -
continued
16 SSDA/Fire PRA
All critical data originally entered into the Safe Shutdown Database (ARTRAK) forms the basis for the Fire PRA
Components
Cables
Cable Routes
Fire Areas/Zones
Intent is to make the SSDA and Fire PRA databases match, one-for-one
17 NFPA-805 Deterministic Methodology Transition
In order to determine the need for Change Evaluations, each fire area must be evaluated to determine if it successfully meets one of the deterministic criteria in NFPA-805
One train maintained free of fire damage (old III.G.1)
Two trains in same area with deterministic solution (Old III.G.2)
3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> barrier between trains
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> barrier with suppression and detection
20 foot of separation with suppression and detection and no intervening combustibles
Alternate Shutdown (old III.G.3)
18 Deterministic Category Impacts
Fire Areas/Zones where redundant trains are located in separate fire areas crediting III.G.1 with operator manual actions on the fire affected train may be transitioned as deterministic; prior approval not required (note that the manual action will be treated as performance based with respect to feasibility)
Fire Areas/Zones crediting III.G.2 that have manual actions will need to be transitioned as risk informed/performance based (under the current rules, they require prior NRC approval; under NFPA-805 rules, they will require a Change Evaluation)
Fire Areas/Zones crediting III.G.3 that have manual actions may be transitioned as deterministic; prior approval not required (but performance based with respect to feasibility)
19 Deterministic Category Impacts Main Control Room Cable Room Equipment Room Pump Room Electrical Switchgear B
Pump B
DC Control Power Cabinet B
3/
Power Cable DC Control Power Main Control Board Pump Room Pump A
Electrical Switchgear A:
DC Control Power Cabinet A:
3/
Power Cable DC Control Power Control Cables
20 Potential Impact of Recent Staff Interpretations
Requirement to protect all associated circuit cables that could negatively impact safe shutdown may be impossible to achieve
Consider a simple example: (See next page)
A hypothetical plant has a switchgear room arrangement that requires one of the switchgear rooms to credit III.G.2 for safe shutdown (20 foot of separationetc.)
21 Potential Impact of Recent Staff Interpretations Main Control Room Cable Room Equipment Room Pump Room Electrical Switchgear A
Pump A
DC Control Power Cabinet A
3/
Power Cable DC Control Power Main Control Board Pump Room Pump B
Electrical Switchgear B
DC Control Power Cabinet B
3/
Power Cable DC Control Power Control Cables
22
Consider a fire in Switchgear Room A
Causes a spurious injection into RCS as a direct result of a single hot short that starts HPI Pump A
Start of HPI Pump A can have a direct impact on success of safe shutdown due to possible increase in Pressurizer level to the point where passing solid water through the Pressurizer Safety Valve fails the valve open
This negative impact results in consideration of spurious HPI pump start as Associated Circuit Potential Impact of Recent Staff Interpretations
23 Potential Impact of Recent Staff Interpretations
24 Potential Impact of Recent Staff Interpretations
25
Consider a fire in Switchgear Room A -
continued
New interpretation that no manual actions are allowed prevents the ability to terminate the fire affected train
Normal controls could be damaged by fire
Design of injection systems normally means there is no redundant isolation valves in series (uses check valves)
Combination of Associated Circuit definition and III.G.2 manual action position would require that the circuit be protected Potential Impact of Recent Staff Interpretations
26 Recommendations
Consider revising policy to allow local operator manual actions to terminate undesirable impacts of spurious actuation of the fire affected train
This is not unlike the existing allowance for local operator manual actions in areas crediting III.G.1
Continuation of the current policy to require protection of associated circuits that are part of the fire affected train is impossible to meet
Would require fire wrap/protection in addition to 3-hour barriers separating trains
27 How This Affects NFPA-805 Transition
Inability to deterministically treat local operator manual actions to terminate injection/impacts on fire affected trains adds unnecessary change evaluations now and in the future (continuing configuration management)
28 Summary
Appendix R Reconstitution Data forms the foundation of the Fire PRA
Recent Staff Interpretations could have a substantial impact on transition scope, cost and schedule