ML070800586
| ML070800586 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 01/31/2007 |
| From: | Gody A Operations Branch IV |
| To: | Minahan S Nebraska Public Power District (NPPD) |
| References | |
| 50-298/07-301 50-298/07-301 | |
| Download: ML070800586 (17) | |
Text
Appendix D Scenario Outline Form ES D-1 Facility: _CNS___________ Scenario No.: _1__ Op-Test No.: _______
Examiners: ________________________ Operators: ___________________________
Initial Conditions: __The plant is operating at 85% power near the end of the current fuel cycle when the crew takes the shift. The plant is in a normal configuration with A Core Spray pump OOS for drawing excessive amps during a surveillance. .
Turnover: The plant is operating at 85% power near the end of the current fuel cycle with A CS pump OOS. OWC has been secured for planned maintenance on SOVs. Load schedule has CNS raising power to 90% with Reactor Recirc flow.
Event Malf. Event Event No. No. Type* Description 1 N/A N Raise power to 90% with reactor recirc flow.
2 2 C RWCU pump seal leak with failure of Group 3 isolation.
3 3 I C Main Steam Flow Instrument fails downscale RRMG drive motor high temperature. Reduce power with 4 4 C,R affected RR pump.
5 5 M Containment leak causes a Scram RPS fails to insert control rods, ARI will be required to insert 6 N/A C control rods.
HPCI fails to start on initiation signal, but can be manually 7 N/A C started.
8 N/A C Startup Valves are failed closed Utilize ECCS and RCIC to maintain containment pressure and 9 N/A N RPV level
- (N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor
Appendix D Scenario Outline Form ES D-1 SCENARIO
SUMMARY
The plant is operating at 85% power near the end of the current fuel cycle when the crew takes the shift. The plant is in a normal configuration with A Core Spray pump, and OWC out of service. The load schedule requires power to be raised to 90% with reactor recirc flow after the crew takes the watch. The running RWCU pump seal fails, causing rising temperatures in the RWCU pump room. The Group 3 isolation signal fails, requiring the operator to close RWCU isolation valves from the control room to stop the leak. The C Main Steam Flow instrument slowly fails downscale, causing reactor level to lower. The crew should respond per abnormal procedure to take manual control of level, and then restore level to the normal operating band in single element control per normal operating procedure. B RRMG set experiences motor bearing high temperature, requiring the crew to lower B RRMG set speed to clear the alarm. The crew should lower Recirc pump speeds together to maintain flow balanced. Then a leak in containment will cause a Scram but a failure of RPS will require the Operator to Initiate ARI to insert control rods. High drywell pressure and low RPV water level are the entry conditions for EOPs. The crew will need to spray the drywell to control containment pressure and temperature. HPCI will fail to auto start, requiring operator action to manually start and control injection to keep level above TAF. The exercise ends when containment pressure has been stabilized, RPV water level has been restored +3 to +54".
CRITICAL TASK
- 1. Insert control rods by ARI
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _1____ Event No.: _1____ Page _1_ of _6_
Event
Description:
_Normal - Raise power to 90% with Reactor Recirc flow..
Time Position Applicants Actions or Behavior 0000 CRS Ensure reactivity brief has been completed with involved Control Room personnel per procedure 2.1.10.
ATC Ensure RR Subsystem flows are balanced ATC Per procedure 2.1.10, Raise power by raising RR pump flow.
Maintain rate of power change consistent with system capabilities as determined by Load Dispatcher and TG limits.
ATC Maintain load change rates to 10 MWe/min.
ATC Monitor various parameters and power indications during all power changes for proper plant response.
ATC Monitor core thermal limits (MFLCPR, MFLPD, and MAPRAT), per Procedure 6.LOG.601, to ensure compliance with Technical Specifications Section 3.2.
ATC Inform CRS when power change is complete Event ends when power has been raised to 90%.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _1____ Event No.: _2____ Page _2_ of _6_
Event
Description:
_Component - RWCU Pump Seal Leakage.
Time Position Applicants Actions or Behavior Respond to 9-3-1/E-10, AREA HIGH TEMP alarm, dispatch station ATC operator to investigate.
Notes 9-4-2/A-5 RWCU HI SPACE TEMP Alarm, and reports this to ATC CRS. Consults ARP 2.3_9-4-2 Determines RWCU isolation valves should have closed due to ATC Group 3 isolation signal Respond to 9-4-2/A-2, REACTOR BLDG EQUIP SUMP E HIGH BOP TEMP. Verify valves swap and sump pump starts to recirc sump CRS Enter EOP 5A due to high space temperature.
CRS Direct ATC to isolate RWCU.
ATC Takes manual action to close RWCU-MO-15 and 18 from panel 9-4.
ATC/CRS Notes that valves close, and reports to CRS Operator may follow up with procedure 2.1.22 as directed from 9 2/A-5 alarm card and follow up with procedure 2.2.66, section 18, ATC/BOP Rapid Removal From Service to isolate RWCU system from guidance in 9-3-1/E-10.
ATC Monitor reactor building temperatures and note they are lowering.
CRS Exit EOP 5A when temperatures lower and RWCU is isolated CRS Consult TS 3.6.1.3 for PCIV function.
The Event ends when Tech Specs have been reviewed and RWCU system is isolated. Area temperatures are lowering.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _1____ Event No.: _3____ Page _3_ of _6_
Event
Description:
Instrument - C Main Steam Line Flow Instrument Failure.
Time Position Applicants Actions or Behavior Note C Steam Flow Instrument lowering and RPV level is lowering.
Report to the CRS. Operator may lower Recirc pump speed to ATC lower power if he does not recognize the steam flow instrument is failing Verifies by other indications that RPV power, pressure, and level ATC are responding as expected for a steam flow instrument failure.
Monitor RFP response and RFP controllers to manual to stop level ATC lowering.
Enters procedure 2.4RXLVL for failure of steam flow instrument.
CRS Assigns critical parameters and scram action point.
ATC Place RFC-LC-83 to Manual. Place control in single element Restore RPV level to 35 inches per procedure 2.2.28.1 after taking ATC actions per 2.4RXLVL Null RFC-LC-83, then place in BAL. Restore level to 35 inches with ATC set tape ATC Report to CRS that RVLC is in Automatic single element control The event ends when RVLC has been restored to automatic in single element control.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _1____ Event No.: _4____ Page _4_ of _6_
Event
Description:
Component - RRMG drive motor bearing high temperature.
Time Position Applicants Actions or Behavior Announces that B RRMG 9-4-3/D-4 , RRMG A/B BRG or OIL ATC TEMP alarm is in.
Verify temperature on recorder RRMG-TR-25 point 15 is high ATC/BOP indicating high drive motor bearing temperature on B RRMG Set CRS Orders that speed of B RRMG be reduced to clear alarm.
Lowers recirc speed per procedure 2.1.10. Monitors reactor power ATC and power to flow map.
ATC/BOP Direct station operator to investigate B RRMG set locally.
ATC Discontinues lowering B RRMG set speed when alarm clears.
B RRMG set is powered from the startup transformer. May discuss CRS/ATC changing power supply to Normal transformer and A RRMG to Startup transformer so that in event of a scram, B would trip.
Event ends when B RRMG speed has been lowered to clear the alarm condition.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _1____ Event No.: _5,6,7,8,9____ Page _5_ of _6_
Event
Description:
Major - Containment Leak causes a Scram. RPS does not insert control rods Time Position Applicants Actions or Behavior ATC/BOP Reports Drywell Pressure and Temp rising Enters 2.4 PC, Directs containment venting. Directs Reactor Scram CRS at 1.5 PSIG DW pressure, direct rapid power reduction at .75 PSIG DW pressure Enters EOPs 1A and transitions to 6A and 7A due to ATWS.
CRS (Condition which requires reactor scram, and reactor power above 3%)
ATC Perform rapid power reduction per 2.1.10, if time permits ATC When DW pressure 1.5PSIG, depress both RX scram pushbuttons.
ATC Place mode switch in Shutdown.
CRS Directs the initiation of ARI.
ATC Initiates ARI and announces control rods are inserted.
Before torus pressure reaches10 psig, direct torus sprays be placed in service.
CRS When drywell temperature exceeds 150 °F, direct drywell FCUs be placed in override .
ATC/BOP Initiate Torus spray and place DWFCUs to override When torus pressure exceeds 10 psig: Ensure PC water level is below 16.5 feet. Ensure drywell temperature and pressure are CRS within DWSIL Direct Recirc pumps be secured. Direct Drywell FCUs be secured. Direct Drywell sprays be placed in service
Appendix D Required Operator Actions Form ES D-2 Page _6_ of _6_
Time Position Applicants Actions or Behavior ATC Trip Recirc Pumps.
BOP Secure Drywell FCUs Place Drywell sprays in service, lower containment pressure as BOP directed.
CRS Direct RPV level be restored and maintained +3 to +54 inches Report HPCI failed to auto start, but can be manually started. Restore ATC/BOP RPV level as directed ATC/BOP Start RCIC to maintain RPV level as required ATC Lower RPV pressure as directed ATC Report the Startup valves failed to open in AUTO and will not open ATC/BOP Verify group isolations with PMIS or hard card May prescribe a wider level band to try to prevent exceeding cooldown CRS limitations Event ends when RPV level is restored and maintained +3 to +54 inches, and drywell pressure has been stabilized below 10 psig.
Appendix D Scenario Outline Form ES D-1 Facility: _CNS___________ Scenario No.: _3__ Op-Test No.: _______
Examiners: ________________________ Operators: ___________________________
Initial Conditions: __The plant is operating at 100% power near the end of the current fuel cycle when the crew takes the shift. The plant is in a normal configuration with A SLC pump tagged out due to failure to achieve adequate discharge flow during SP 6.SLC.101 .
Turnover: The plant is operating at 100% power near the end of the current fuel cycle with A SLC pump OOS. Issues in the Intake Structure due to low river level at 874 feet.
Event Malf. Event Event No. No. Type* Description 1 N/A N Secure C CWP as requested by Work Control.
2 2 C REC pump trip 3 3 C Service Water Zurn Strainer plugs 4 4 C Loss of MCC-S, loose additional 2 REC pumps 5 N/A N Scram due to low REC pressure Loss of 4160V busses A and B due to failure to transfer to 6 N/A C Startup Transformer on the turbine trip Lockout on 4160G prevents it from closing in on Emergency 7 7 C transformer or DG#2 Main Steam Line rupture in the Drywell causing containment 8 8 M temperature to exceed 280 degrees F requiring Emergency Depressurization Core Spray A pump fails to Auto start, but can be started 9 N/A C manually RHR-MO-25A and 31A fail to open, preventing RPV injection 10 N/A C and drywell sprays with A RHR loop.
- (N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor
Appendix D Scenario Outline Form ES D-1 SCENARIO
SUMMARY
When the crew takes the watch, the plant is at 100% power. Work Control calls and requests C CWP be secured for planned cleaning of C CW bay. A loss of A REC pump requires crew to start another REC pump and monitor system pressure. Then the A service water zurn strainer plugs, requiring the crew to shift service water pumps and bypass the zurn strainer to restore adequate service water pressure on the A side.
Loss of MCC-S causes 2 additional REC pumps to trip, which will require the crew to scram the reactor due to inadequate REC pressure. When the turbine trips, A and B 4160 V busses fail to transfer to the Startup Transformer. 4160V bus G has a lockout, and cannot be energized from the Emergency Transformer or DG#2. The loss of TEC will cause the MSIVs to close on high space temperature. When the MSIVs close, the A MSL ruptures upstream of the inboard MSIVs and causes drywell temperature and pressure to rise. RHR-MO-31A fails to open when lining up to spray the drywell resulting in drywell temperature continuing to rise till emergency depressurization is required. RHR-MO-25A fails to open on low pressure and cannot be opened from the control room. A Core Spray pump fails to start automatically, but can be manually started. The scenario ends when the reactor is shutdown, emergency depressurization is complete, RPV water level has been restored and maintained +3 to +54" CRITICAL TASK
- 2. Emergency depressurize when Primary containment temperature cannot be maintained < 280 degrees F.
- 3. Restore RPV level above TAF with low pressure ECCS after ED prior to fuel centerline temperature exceeding 1800 degrees F.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _1____ Page _1_ of _7_
Event
Description:
_Normal - Secure a CWP.
Time Position Applicants Actions or Behavior 0000 BOP Maintenance requests C CWP be secured BOP Per procedure 2.2.3 Section 7, secure C CWP .
BOP Monitor main condenser vacuum BOP Inform CRS of CWP status and condenser vacuum.
CRS Ensure condenser vacuum being monitored.
Event ends when CWP secured and condenser vacuum has stabilized .
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _2____ Page _2_ of _7_
Event
Description:
_Component - REC pump trip.
Time Position Applicants Actions or Behavior Respond to alarm M-1/B-1, REC PUMP A FAILURE. Report A BOP REC pump has tripped to CRS BOP Start another REC pump Monitor REC temperatures and pressures, and restore system as BOP necessary.
BOP Dispatch station operator to investigate cause of trip Report to CRS when REC parameters have been restored to BOP normal.
CRS Enter and direct 5.2REC BOP Perform 5.2REC as directed.
The Event ends when an REC pump has been started and REC parameters have been restored to normal.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _3____ Page _3_ of _7_
Event
Description:
Component -Service Water system Zurn strainer plugs.
Time Position Applicants Actions or Behavior Respond to alarm A-4/D-7 SERVICE WATER STRAINERS A BOP HIGH D/P, dispatch station operator to ensure strainer is in backwash Direct SWPs be swapped to place 2 pumps running on DIV 2 side CRS and only 1 pump on DIV 1 side. Enter and direct 5.2SW.
BOP Swap pumps as directed per procedure 2.2.71.
BOP Monitor SW system pressure .
Dispatch a station operator to bypass A sw Zurn strainer per BOP procedure 2.2.71 Section 13.
The event ends when BOP has swapped SWPs to division without alarm and has dispatched operator to bypass the strainer.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _4,5____ Page _4_ of _7_
Event
Description:
Component - Loss of MCC-S.
Time Position Applicants Actions or Behavior Respond to alarms C-3/A-9, 480V BUS 1G MCC-S BKR TRIP, and BOP C-3/G-9, 480V BUS 1G GROUND Perform rapid power reduction with recirc flow to 44 mil/lbm per ATC procedure 2.1.10.
Report that only 1 REC pump is running and cannot restore system BOP pressure after completion of immediate operator actions.
CRS Enter and direct 5.2REC, direct reactor scram.
ATC Scram reactor, perform actions of procedure 2.1.5.
BOP Restore REC and ventilation as directed by alarm card and 5.2REC Event ends when reactor is scrammed and steps of 5.2REC are completed.
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _6,7____ Page _5_ of _7_
Event
Description:
Component - Loss of 4160 Busses A and B Time Position Applicants Actions or Behavior BOP Reports 4160V Busses A and B failed to transfer to Startup Transformer when the Main Turbine Tripped .
BOP Reports that 4160V Bus G is de-energized, and has a lock out.
CRS Enter and direct 5.3EMPWR.
BOP Determine status of electric power and equipment available.
BOP Performs actions of alarm cards and 5.3EMPWR Event ends when crew knows status of electric plant and alarm card and 5.3EMPWR actions are completed
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _8,10____ Page _6_ of _7_
Event
Description:
Major - Main Steam Line rupture in the Drywell Time Position Applicants Actions or Behavior ATC/BOP Report MSIVs closed due to loss of TEC cooling ATC Report that drywell temperature and pressure are rising.
Enter EOP 3A due to rising drywell temperature and pressure.
Direct DWFCUs be taken to Override when DW Temp > 150 CRS degrees F. Direct Torus sprays be placed in service before Torus pressure reaches 10 psig ATC/BOP Place DWFCUs to Override, place Torus sprays in service Before drywell temperature reaches 280 degrees F, direct DWFCUs CRS and RR pumps be secured, Check drywell temperature within DWSIL (GRAP 9), start drywell sprays.
Place drywell sprays in service, report that RHR-MO-31A lost BOP indication when attempted to open.
Determine from trend of drywell temperature and pressure that BOP RHR-MO-31A is not open.
Direct emergency depressurization when drywell temperature CRS cannot be restored and maintained below 280 degrees F.
BOP Open 6 SRVs, report reactor pressure lowering Event ends when emergency depressurization is complete and RPV level has been restored to +3 to +54 inches
Appendix D Required Operator Actions Form ES D-2 Op-Test No.: _____ Scenario No.: _3____ Event No.: _9____ Page _7_ of _7_
Event
Description:
Component - Core Spray pump fails to auto start Time Position Applicants Actions or Behavior BOP Report B Core Spray pump failed to start on 2# DW signal BOP Attempt to start A Core Spray pump with control switch BOP Report A Core Spray pump is running to CRS After emergency depressurization, use A Core Spray to recover BOP RPV level to +3 to +54 inches Event ends when A Core Spray pump has been started and RPV level has been restored to +3 to +54 inches