ML091170390
| ML091170390 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 04/03/2009 |
| From: | Ryan Lantz Operations Branch IV |
| To: | Blevins M Luminant Generation Co |
| References | |
| 50-445/09-301, 50-446/09-301 | |
| Download: ML091170390 (6) | |
Text
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc Facility:
CPNPP 1 & 2 Scenario No.:
1 Op Test No.:
March 2009 NRC Examiners:
Operators:
Initial Conditions:
67% power MOC - RCS Boron is 922 ppm (by sample).
Motor Driven Auxiliary Feedwater Pump 1-02 OOS for coupling repair. RTS in 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
Turnover:
Maintain steady-state power conditions while Heater Drain Pump repairs are made.
Critical Tasks:
Emergency borate due to two (2) stuck Control Rods.
Perform actions to identify and isolate the ruptured Steam Generator.
Perform actions to cooldown and depressurize the Reactor Coolant System.
Event No.
Malf. No.
Event Type*
Event Description 1
+ min TC09D FW03B C (BOP, SRO)
Main Feedwater Pump B trip with Auto Turbine Runback failure.
2
Letdown Isolation Valve (HV-8160) fails closed.
Place Excess Letdown in service.
3
TS (SRO)
Station Service Water Pump (1-02) trip.
4
TS SRO Steam Generator #1 Tube Leak at 175 gpd.
5
+ min SG01A M (ALL)
Steam Generator #1 Tube Rupture at 650 gpm.
6
+ min RD04M14 RD04P8 C (RO)
Two (2) Control Rods fail to insert on Reactor trip. Emergency boration required.
7
+ min RH01C C (BOP)
Residual Heat Removal Pump 1-01 fails to auto start on Safety Injection signal.
(N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor, (TS)Technical Specifications
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc SCENARIO
SUMMARY
NRC #1 The crew will assume the watch with power reduced due to a Heater Drain Pump Seal failure. Power is maintained per IPO-003A, Power Operations until repairs are made.
The first event is a trip of Main Feedwater Pump B with an automatic Turbine Runback failure. The crew responds per ABN-302, Feedwater, Condensate, Heater Drain System Malfunction. When it is determined that automatic plant response has not activated, a manual Turbine Runback will be initiated. The crew will stabilize load at 700 MWe.
When ABN-302 actions are complete, a loss of Letdown occurs due to a Letdown Isolation Valve failing closed. Actions are per ABN-105, Chemical and Volume Control System Malfunction, and require controlling Charging and Seal Injection flows until Letdown can be restored. The RO will be directed to place Excess Letdown in service.
This is followed by a trip of Station Service Water Pump 1-02. The crew will enter ABN-501, Station Service Water System Malfunction. Initial operator actions include placing the Train B Emergency Diesel Generator in PULL-OUT. The SRO will refer to Technical Specifications.
The next event is a Steam Generator #1 tube leak of 175 gpd. Crew actions are per ABN-106, High Secondary Activity. The SRO will refer to Technical Specifications.
When Technical Specifications are referenced, a Steam Generator #1 tube rupture occurs and leakage rises to 650 gpm. An uncontrolled loss of Pressurizer level will require a Reactor trip, initiation of Safety Injection and entry into EOP-0.0A, Reactor Trip or Safety Injection. At Step 13, a transition to EOP-3.0A, Steam Generator Tube Rupture will occur to isolate the ruptured Steam Generator. The event is complicated when two Control Rods fail to insert. Additionally, Residual Heat Removal Pump 1-01 fails to auto start on the Safety Injection signal.
The scenario is terminated when the ruptured Steam Generator is isolated, feedwater flow is properly aligned and the Reactor Coolant System cooldown and depressurization is commenced.
Risk Significance:
Risk important components out of service:
Auxiliary Feedwater Pump 1-02 Failure of risk important system prior to trip:
Station Service Water Pump 1-01 Risk significant core damage sequence:
Steam Generator Tube Rupture Risk significant operator actions:
Emergency borate due to 2 stuck rods Start Residual Heat Removal Pump 1-01 Identify and isolate the ruptured SG Cooldown and depressurize the RCS
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc Facility:
CPNPP 1 & 2 Scenario No.:
2 Op Test No.:
March 2009 NRC Examiners:
Operators:
Initial Conditions:
~1X10-8 amps BOC - RCS Boron is 1545 ppm (by sample).
Steam Dump System in service for RCS Temperature Control.
Turnover:
Raise Power to 2% in preparation for plant startup to 100% power.
Critical Tasks:
Restore feedwater flow from the Turbine Driven Auxiliary Feedwater Pump.
Restore power to at least one 6900 VAC Safeguards Bus.
Initiate emergency boration due to loss of Digital Rod Position Indication.
Event No.
Malf. No.
Event Type*
Event Description 1
+ min R (RO)
Raise Reactor power to 2%.
2
TS (SRO)
Motor Driven Auxiliary Feedwater Pump (1-01) trip.
3
Volume Control Tank Level Transmitter (LT-112) fails low.
4
TS (SRO)
Pressurizer Pressure Channel (PT-455) fails low.
5
+ min Tornado Warning from the National Weather Service.
6
+ min ED01 M (ALL)
Loss of All AC Power due to Loss of Offsite Power.
7
+ min EG06A C (BOP)
Emergency Diesel Generator (1-01) fails to start.
8
+ min EG15B C (BOP)
Emergency Diesel Generator (1-02) fails to auto and emergency start; EDG (1-02) starts upon Normal Start Switch actuation.
(N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor, (TS)Technical Specifications
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc SCENARIO
SUMMARY
NRC #2 The crew takes the shift with a Plant Startup in progress and will continue raising power to approximately 2% per IPO-002A, Plant Startup from Hot Standby.
When conditions are stable, Motor Driven Auxiliary Feedwater Pump 1-01 will trip. The crew will refer to ABN-305, Auxiliary Feedwater System Malfunction and determine that Steam Generator levels are slowly decreasing and start the Turbine Driven Auxiliary Feedwater Pump. The SRO will refer to Technical Specifications.
The next event is the failure of Volume Control Tank level transmitter LT-112. Actions per ABN-105, Chemical and Volume Control System Malfunction will be performed. This event will disable automatic makeup flow to the Volume Control Tank.
When ABN-105 actions are complete, Pressurizer Pressure Channel PT-455 will fail low. The crew will respond per ABN-705, Pressurizer Pressure Malfunction, and ensure Pressurizer Heaters are controlled and Power Operated Relief Valves remain closed. The SRO will refer to Technical Specifications.
When plant conditions are stable, a tornado warning from the National Weather Service will require entry into ABN-907, Acts of Nature. This is the precursor event to a Loss of Offsite Power.
The next event is a Loss of Offsite Power with a failure on each Emergency Diesel Generator resulting in a Total Loss of All AC. The crew enters EOP-0.0A, Reactor Trip or Safety Injection and then exits to ECA-0.0A, Loss of All AC Power, at Step 3. As an alternative the Unit Supervisor may directly enter ECA-0.0A. While in ECA-0.0A, the crew will take actions that start Emergency Diesel Generator 1-02.
The RO may initiate an emergency boration due to loss of Digital Rod Position Indication (DRPI) while in ECA-0.0A if rod position is not observed prior to loss of DRPI.
Once Emergency Diesel Generator 1-02 is started and the breaker is closed in ECA-0.0A, a return to the procedure and step in effect is required. The crew will return to EOP-0.0A and then transition to EOS-0.1A, Reactor Trip Response when it is determined that Safety Injection is not required.
The scenario is terminated after EOS-0.1A, Reactor Trip Response is entered and the actions to stabilize the Unit are performed.
Risk Significance:
Risk important components out of service:
None Failure of risk important system prior to trip:
Loss of MDAFW Pump 1-01 Risk significant core damage sequence:
Loss of all AC Power Risk significant operator actions:
Restore Auxiliary Feedwater flow Restore power to 6.9 KV Safeguards Bus Initiate emergency boration
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc Facility:
CPNPP 1 & 2 Scenario No.:
3 Op Test No.:
March 2009 NRC Examiners:
Operators:
Initial Conditions:
100% power MOC - RCS Boron is 910 ppm (by sample).
Motor Driven Auxiliary Feedwater Pump 1-02 OOS for coupling repair. RTS in 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
Turnover:
Maintain steady-state power conditions.
Critical Tasks:
Perform actions to identify and isolate faulted Steam Generators.
Manually actuate both trains of Phase A Containment Isolation.
Secure Reactor Coolant Pumps due to a loss of subcooling.
Event No.
Malf. No.
Event Type*
Event Description 1
TS (SRO)
Reactor Coolant System Loop 2 Tcold Transmitter (TI-421B) fails high.
2
TS (SRO)
Steam Generator #4 Level Transmitter (LT-554) fails low.
3
- 1 Seal failure on Reactor Coolant Pump #2 between 6 and 8 gpm.
4
+ min R (RO)
Unit Power reduction.
5
- 2 Seal failure on Reactor Coolant Pump #2 requiring manual trip.
6
+ min MS02 M (ALL)
Main Steam header leak.
Small Break Loss of Coolant Accident.
7
+ min MS08 A/B/C/D C (RO)
Main Steam Isolation Valves fail to automatically close.
8
+ min RP09A RP09B C (BOP)
Train A Containment Isolation Phase A actuation failure.
Train B Containment Isolation Phase A actuation failure.
(N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor, (TS)Technical Specifications
Appendix D Scenario Outline Form ES-D-1 CPNPP March 2009 NRC Sim Scenario ES-D-1 Rev f.doc SCENARIO
SUMMARY
NRC #3 The crew initially takes the shift at 100% power with no scheduled activities per IPO-003A, Power Operations. Auxiliary Feedwater Pump 1-02 is out-of-service for coupling repair.
The first event it is a failure of Tcold instrument, TI-421B. Operator actions are per ABN-704, TC/N-16 Instrumentation Malfunction and require stopping Control Rod motion and stabilizing RCS temperature and Pressurizer level. The SRO will refer to Technical Specifications.
Once systems are stable, a Feedwater Flow instrument fails low. Operator response is per ABN-708, Feedwater Flow Instrument Malfunction. The operator must take manual control of the affected Feed Control Valve to prevent a Unit trip on high Steam Generator water level. After manual control is established, an alternate channel is selected and automatic control restored.
The next event is a failure of #1 Seal on Reactor Coolant Pump #2. Crew actions are per ABN-101, Reactor Coolant Pump Trip/Malfunction. The crew should determine that based on leakoff flow and stable seal temperatures an orderly Unit shutdown to have the RCP secured within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is required.
At this point the crew will commence a power reduction per IPO-003A, Power Operations. When a sufficient down power has been achieved, the #2 Seal on Reactor Coolant Pump #2 will fail requiring a Reactor trip, stopping of the RCP and isolation of seal return from the affected pump per ABN-101, Reactor Coolant Pump Trip/Malfunction.
On the Unit trip, a Main Steam header leak will occur downstream of the Main Steam Isolation Valves.
Additionally, the Main Steam Isolation Valves (MSIV) fail to automatically or manually close along with a Train A and Train B Containment Isolation Phase A failure.
The crew enters EOP-0.0A, Reactor Trip or Safety Injection and then transitions to EOP-2.0A, Faulted Steam Generator Isolation. Once entry into EOP-2.0A is made, a transition to ECA-2.1A, Uncontrolled Depressurization of All Steam Generators is required. When Auxiliary Feedwater flow is throttled in ECA-2.1A, the MSIVs on all Steam Generators will be closed. FRH-0.1A, Response to Loss of Secondary Heat Sink will be entered and exited due to an operator induced reduction in feedwater flow.
The crew will transition from ECA-2.1A, Uncontrolled Depressurization of All Steam Generators back to EOP-2.0A, Faulted Steam Generator Isolation and then to EOP-1.0A, Loss of Reactor or Secondary Coolant.
This scenario is terminated when a Reactor Coolant System cooldown and depressurization is commenced.
Risk Significance:
Risk important components out of service:
Auxiliary Feedwater Pump 1-02 Risk significant core damage sequence:
Faulted SG with SBLOCA Risk significant operator actions:
Initiate Phase A Containment Isolation Manually Initiate MSIV Closure Isolate all Faulted SGs