ML16221A558
ML16221A558 | |
Person / Time | |
---|---|
Site: | Davis Besse |
Issue date: | 08/02/2016 |
From: | Operations Branch III |
To: | FirstEnergy Nuclear Operating Co |
Shared Package | |
ML15274A359 | List: |
References | |
Download: ML16221A558 (48) | |
Text
Facility: Davis-Besse Scenario No.: 2 Op Test No.: DB NRC 2016 Examiners: Operators: SRO ATC BOP Initial Conditions:
- 70% Power
- ULD is in manual (will not go into auto due to issue with 3 RCP operation)
Turnover: Maintain 70% Power Planned: Normal shift routines Critical tasks: 1. ATWS (CT24)
- 2. Isolate overcooling SG (CT-17)
Event Malf. Event Type* Event No. No. Description I-ATC/BOP/SRO 1 Power range (NI5) high failure
( TS) 2 C-ATC/SRO Makeup Filter high differential pressure 3 I-BOP/SRO MFW control valve d/p instrument fails low R-ATC/SRO 4 Dropped rod (TS) 5 N-BOP/SRO Remove MFP from service 6 M-All MFP trip - Loss of Main Feedwater/ATWS 7 C-BOP/SRO Stuck Open Main Steam Safety Valve
- (N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor
DAVIS-BESSE 2016 NRC SCENARIO 2 The Crew will take the watch with power at 70% with 1-1 RCP out of service due to a maintenance issue with the upper bearing. Direction for the crew is to maintain 70%
power. Following turnover the lead evaluator will cue the failure high of Power Range Nuclear Instrument NI-5, which will cause rods to insert due to the ICS system responding to the failed high signal. The crew will take actions to stabilize the plant per abnormal procedure DB-OP-02505, Nuclear Instrument Failures. The Unit Supervisor will direct placing RPS Channel 2 in Manual Bypass and the Power Range Test Module in Test Operate. The Unit Supervisor will enter applicable Technical Specification (T.S.
3.3.1) for RPS Channel 2 in Manual Bypass (TS).
At the Lead Evaluators cue event 2 will be inserted and annunciator 2-4-A, Letdown or MU Filter Differential Pressure Hi, will alarm due to high differential pressure across the #1 Makeup Filter (PDI MU13 greater than 25 psid). The crew will implement alarm procedure actions, validate #1 Makeup Filter differential pressure is high, and swap to #2 Makeup Filter using DB-OP-06006, Makeup and Purification System.
Event 3 will be initiated at the cue from the Lead Evaluator which will fail low PDT SP5A1, MFW control valve d/p instrument. The crew will identify the failure and respond by taking manual control of HIC ICS36A/HIC ICS36B, Main Feed Pump Turbine Hand/Auto Stations, or may take actions per abnormal procedure DB-OP-02526, Primary to Secondary Plant Upset. Once the plant is stabilized the crew will select the Y instrument PDT SP5A2 and restore ICS stations to auto. After ICS is restored to automatic control the scenario will proceed to event 4.
Event 4 will have the crew respond to a dropped rod. Abnormal procedure DB-OP-02516, CRD Malfunctions, will be entered and power reduced to 33% power based on the three RCP configuration. The plant will be stabilized and troubleshooting of the fault will be requested, but it is not the intent of this scenario to recover the rod. The Unit Supervisor will enter applicable technical specifications 3.1.4 and 3.1.5 for the dropped rod (TS).
With power being maintained at approximately 33%, the Lead Evaluator will proceed to event 5 by providing a Shift Manager cue to remove #1 MFP from service. The BOP will remove #1 MFP from service IAW DB-OP-06224, Main Feed Pump and Turbine.
The Lead Evaluator will next cue event 6 and 7 resulting in the loss of #2 MFP and a loss of all Main Feed Water with an Anticipated Transient Without a Scram (ATWS). The ATC will perform immediate actions and trip the reactor by de-energizing simultaneously the E2 and F2 busses, and verify power is lowering in the intermediate range (CT-24).
The crew will continue to perform actions IAW the Emergency Procedure DB-OP-02000.
The crew will identify Overcooling due to a stuck open safety valve and route to section 7 of DB-OP-02000 to isolate the OTSG and terminate the overcooling (CT-17). The scenario will be terminated at the discretion of the Lead Evaluator.
Indications Available:
- Annunciator 14-4-D, ICS FW Limited By Rx Pwr
- Annunciator 14-6-D, ICS In Track
- Annunciator 5-1-H, RPS Ch 2 Trip
- Annunciator 5-2-H, RPS Hi Flux Trip
- Rods inserting Recognize that NI5 has failed high using indications available Crew listed above Direct the implementation of DB-OP-02505, Nuclear Instrumentation Failures SRO NOTE: If not quickly diagnosed the crew may enter DB-OP-02526, Primary to Secondary Heat Transfer Upset Place Rod Control Panel in manual and Reactor Demand Station ATC in hand Reactor power is stabilized and held constant If Tave is > 2°F from setpoint then place both Feedwater Loop BOP Demands to hand and adjust to stabilize RCS Tave Crew Identify NI5 as the instrument failed high Enter TS 3.3.1, Condition A for function 1,7, and 8 SRO Refer to TS 3.3.16 (only 3 ARTS Channels required)
Notify SM to refer to reactivity management, event notifications, SRO and Fleet Update requirements Brief contingency actions for Power Range instrument failure
- RFR will not actuate SRO
- TBV Bias for reactor trip will not function
- Main FW block valves will not auto close
SM If necessary, Role-play Shift Manager and direct placing RPS Channel 2 in manual bypass, Test Module in Test Operate, CUE and restoring ICS controls to auto.
Directs placing RPS 2 in Manual Bypass per DB-OP-06403, SRO Reactor Protective System (RPS) and Nuclear Instrumentation (NI) Operating Procedure
- Obtain RPS Manual Bypass key and Ch2 door key
- Check MANUAL-BYPASS light is BRIGHT
- Check SUB-SYSTEM light is DIM BOP Place the Power Range Test Module for NI5 in TEST OPERATE Directs placing ICS in Auto per DB-OP-06401, Integrated Control SRO System Operating Procedure Crew Briefs returning ICS stations to automatic Depress AUTO on HC NI44, ROD CONTROL PANEL ATC Verify Tave at setpoint Depress AUTO on HIC ICS20, REACTOR DEMAND If necessary place Feedwater Loop Demands in auto
Indications Available:
- PDI MU13 indicates >25 PSID
- 2-4-A LETDOWN OR MU FILT P HI Recognize Makeup Filter high differential pressure for in service Crew Makeup Filter 1 (indications available listed above)
Implement DP-OP-02002 Letdown/Makeup Alarm Panel 2 ATC Annunciators for 2-4-A LETDOWN OR MU FILT P HI Validate Makeup Filter high differential pressure with PDI MU13 ATC indicating >25 psid Direct placing Makeup Filter 2 in service in accordance with DB-SRO OP-06006, Makeup and Purification System Verify Makeup Filter 2 is not aligned as the Purification Demin SRO/ATC Filter (Prerequisite)
SM If necessary, Role-play Shift Manager and inform the SRO that Makeup Filter 2 has been verified to not be aligned as the CUE Purification Demin ATC Swap to Makeup Filter 2 Open MU12B, MAKEUP FILTER 2 INLET ISOLATION, using ATC HISMU12B.
Close MU12A, MAKEUP FILTER 1 INLET ISOLATION, using ATC HISMU12A.
Ensure work request initiated to have filter replaced (alarm Crew procedure guidance)
At Lead Evaluator discretion proceed to Event 3
Indications Available:
- 14-4-E, ICS INPUT MISMATCH
- MFP speed increasing Crew Recognize PDT SP5A1 failing low Place HIC ICS36A/HIC ICS36B, MAIN FEED PUMP TURBINE BOP HAND/AUTO STATIONS, in HAND Lower MAIN FEED PUMP TURBINE speed to restore valve d/p NOTE: Depending on how quickly the crew recognizes the failure, the SRO may implement the Pri/Sec upset procedure and take other ICS station controls to manual in addition to HIC ICS36A/HIC ICS36B and lowering Feed pump speed.
May direct BOP actions per DB-OP-02014, MSR/ICS Alarm Panel 14 Annunciators SRO
- Determine which instrument has caused alarm (at SASS cabinet)
Determine which instrument has caused alarm (at SASS cabinet).
BOP May depress the SASS Annunciator RESET pushbutton for the appropriate module SM If necessary Role-play Shift Manager and direct selecting CUE good instrument and returning ICS controls to Auto SRO Verify good instrument and direct MFW Valve P control transferred to the Y instrument per DB-OP-06407, NNI Operating Procedure, Section 4.1.
BOP Select the Y MFW Valve P instrument SP5A2 BOP Adjust speed as needed and place HIC ICS36A/HIC ICS36B, MAIN FEED PUMP TURBINE HAND/AUTO STATIONS, in Auto On Lead Evaluators discretion, proceed to Event 4 and 5
Indications Available:
- Annunciator 5-1-E, CRD TRBL
- Annunciator 5-2-E, CRD ASYMETRIC ROD
- Control Rod 4-9 Rod Bottom light ON Crew Recognize that a single Control Rod has inserted into the core SRO Implement DB-OP-02516, CRD Malfunctions SRO Direct Power reduction to 33% at 3% RTP per minute (3 RCPs)
- Set ULD MAX LOAD LIMIT to 33% RTP
- Set ULD Rate of Change to 3% RTP per minute ATC NOTE: Annunciator 14-5-C, ICS Hi Load Limit, will alarm when Max Load Limit is below current Unit Load Demand REFER TO DB-OP-02504, Rapid Shutdown (Att.2, Power SRO Reduction using ULD Max Load Limit)
Direct BOP to perform Attachment 6, Balance of Plant Actions for SRO Rapid Shutdown Notify Equipment Operators to commence Attachment 15, Field SRO Actions for Rapid Shutdown Notify the System Control Center (SCC) Load Dispatcher of the SRO unit load reduction IF only 3 RCPs are in service, SRO THEN review Attachment 16, Three Reactor Coolant Pump Operation If directed by US (annunciator 4-2-E, PZR LEVEL LO alarms due ATC to the dropped rod Tave transient) then reduce MU32 (PZR level control) set point to approximately 180 inches Notify SM to review Reactivity Management, Event Notifications, SRO and Fleet Reporting requirements and to Notify Duty Engineering Manager or Reactor Engineering Supervisor to review Att. 5
Monitor Reactor Power to confirm power is being reduced at the Crew expected rate IF Pressurizer Level is greater than 228 inches, then refer to SRO Technical Specification 3.4.9 Condition A Monitor for Regulating Rod Insertion Limits during the Shutdown ATC (Technical Specification 3.2.1)
As directed by SRO, set ULD minimum load limit to 13%
ATC (guidance from Att. 16 for 3 RCP operation)
Perform Attachment 6, Balance of Plant Actions for Rapid Shutdown:
- Stop #1 MFP (performance steps below)
- Stop LPFW Drain Pumps/Direct EO to close HD5/HD6
- Establish one Condensate Pump in operation if <3.5 MPPH flow SRO Direct Shutdown of MFP 1 BOP Place HIC ICS 36B, #1 MFW PUMP SPEED, station in HAND Lower #1 MFPT speed to approximately 3950 RPM using HIC BOP ICS 36B, #1 MAIN FEEDPUMP SPEED Adjust the MDT 20 output to indicate zero amps reading on the BOP XFER METER Depress MANUAL on HIS 805C2 AND check MANUAL BOP illuminates Reduce MFPT 1 speed by turning HS 805D, TURBINE SPEED BOP MDT 20 PISTOL GRIP, to DECREASE until green LSS light IL 805A is LIT BOP Trip MFPT 1 Check the following lights are LIT:
- Red TRIP light
- Green LP STOP VALVE closed
- Green HP STOP VALVE closed Check FW 488, MAIN FEED PMP 1 DISCHARGE NON-RETURN, is seated as indicated by the following:
- Deaerator levels approximately equal Direct an Equipment Operator to Complete MFP Shutdown to BOP Turning Gear Operation Verify S/G Load Ratio H/A station in hand with 0 degree ATC/BOP differential temperature demand Notify Reactor Engineering/Duty Engineering Manager to SRO reference Attachment 5 SRO Request I&C to investigate referring to Attachment 1 Refer to DB-OP-02516 Attachment 3 to determine Tech Spec applicability:
- Enter Tech Spec. 3.1.4 for the dropped rod, Condition A and D
- Enter Tech Spec. 3.1.5 Cond A
- Verify SDM within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> SM If necessary Role-play Shift Manager and inform SRO the CUE Shift Engineer is verifying SDM On Lead Evaluators discretion, proceed to Event 6 and 7
Indications Available:
- Annunciator 8-4-B MFPT 2 TRIP
- Annunciator 5-1-F ARTS CH TRIP
- MFP 2 Control Indications indicate Tripped Crew Recognize Loss of Feedwater/ARTS Channel Trip and the reactor has not tripped ATC Perform DB-OP-02000 immediate actions
- Attempt to manually trip reactor
- Critical Task
- Report failure of manual pushbuttons to trip reactor
- *De-energize E2 and F2 (CT24)
- Re-energize E2 and F2
- Verify power decreasing on the Intermediate Range Complete DB-OP-02000 immediate actions ATC
- Verify Turbine Tripped
- VERIFY all Turbine Stop Valves OR Control Valves are closed SRO Implement DB-OP-02000 SRO/ATC Verify Immediate Actions SRO Implement any necessary Specific Rules Actions BOP Verify SFRCS has Initiated and Isolated (reverse P)
SRO Implement any necessary Symptom Mitigation Sections Crew Recognize Overcooling Symptoms SRO Route to DB-OP-02000, Section 7 for Overcooling Implement Attachment 8, Place MU/HPI/LPI in Service
- Start/Verify running both CCW Pumps
- Start both LPI Pumps
- Open DH 64 and DH 63
- Transfer Makeup Pump suctions, MU6405 & MU3971, to the BWST (depress off)
- Set Pressurizer Level Controller to 100 inches
- Start Standby Makeup Pump 2
- Lock MU Pump suctions, MU6405 & MU3971, on the BWST
- Verify Pressurizer heaters are off (If PZR Level <40 inches)
- Isolate Letdown by closing MU2B
- Open MU6421
- Throttle open MU6419 as needed
- Direct EO to open MU6423B ATC Control MU/HPI/LPI per Specific Rule 3 and Att. 13 Crew Diagnose stuck open safety SG2 Booth If security is called inform that steam continues to issue from Cue aux building roof steam relief exhaust pipe SRO Route to Step 7.11 due to SFRCS Isolation Trip Route to Step 7.20 due to unisolable steam leak (safety valve SRO does not reseat)
Route to Step 7.25 due to Low MS Line Pressure Trip and #2 SG SRO identified as causing the overcooling Verify proper operation of AFW trains feeding OTSG 1. REFER TO Table 1, SFRCS Actuated Equipment
- Identify AF3872 failed open/attempt to close
- Critical BOP Task * *Close AF599, AFW to SG2 Stop Vlv (CT-17) * *Place controller LIC6451 in manual and control flow to #1 SG, or lower AFP 2 speed to control flow (controller monitors #2 SG level with AF3872 open)
NOTE: AF3872 will fail to close As the SG 2 boils dry, THEN check Reactor Coolant System Crew Cooldown rate lowers to less than 100 °F/hr.
Control the AVV on the non-isolated SG (SG 1) to maintain RCS BOP temperature constant OR slightly lowering Begin to depressurize the RCS using Pressurizer Spray AND ATC Heaters to maintain pressure close to the minimum adequate subcooling margin, but above the RCP NPSH limits of Figure 1.
EAL Alert based on SA3 (Automatic actions fail to shutdown the reactor. Manual actions from the control room area are successful.)
At the discretion of the Lead Evaluator the scenario can be terminated
Justification for Critical Tasks A. Shutdown Reactor - ATWS (CT24)
The reactor must be shut down prior to proceeding since the Technical Bases Document accident mitigation is based on having the reactor shut down. De-energize E2 and F2 to remove electrical power from control rod drive system and shut down the reactor.
B. Isolate Overcooling Steam Generator(s) (CT-17)
AF 599, AFW to SG 2, must be closed to isolate flow to #2 SG due to AF3872 failing to close. Controller LIC6451 is placed in manual, or AFP 2 speed lowered to mitigate overcooling caused by AFW Pump 2 flow to SG1 due to the controller receiving level input from #2 SG level with AF3872 open (controller input signal switches to SG1 upon AF3872 leaving the open position indication).
SIMULATOR SETUP INFORMATION
- 1. Simulator Setup a) 70% Power b) RCP 1-1 OOS (Upper bearing issue) c) Makeup Filter 1 in service d) Auto Reactor trip prohibited e) AF3872 failed open f) Steam Safety on #2 OTSG fails to close once lifted
- 2. Procedures Used by the crew a) DB-OP-02505, Nuclear Instrument Failures b) DB-OP-06403, RPS and Nuclear Instrumentation c) DB-OP-06401, Integrated Control System Operating Procedure d) DB-OP-02002, Letdown/Makeup Alarm Panel 2 e) DB-OP-06006, Makeup and Purification System f) DB-OP-02526, Primary to Secondary Plant Upset g) DB-OP-02014, MSR/ICS Alarm Panel 14 h) DB-OP-06407, NNI Operating Procedure i) DB-OP-02516, CRD Malfunctions j) DB-OP-02504, Rapid Shutdown k) DB-OP-02000, RPS, SFAS, SFRCS Trip, or Steam Generator Tube Rupture For Simulator Instructor/Communicator a) DB-OP-06006, Makeup and Purification System, section 3.24 b) DB-OP-02516, CRD Malfunctions, section 4.1 c) DB-OP-02504, Rapid Shutdown, Attachment 6 (BOP actions)
Facility: Davis-Besse Scenario No.: 3 Op Test No.: DB NRC 2016 Examiners: Operators: SRO ATC BOP Initial Conditions:
- 100% Power Turnover: Maintain 100% Power Planned: Shift routines Critical tasks: 1. Establish MU/HPI cooling (CT-14)
- 2. Trip All RCPs (CT-1)
Event Malf. Event Type* Event No. No. Description C-ATC/BOP/SRO 1 RCS pressure NNI input fails low (TS)
C-BOP/SRO 2 HPFW Heater tube leak R-ATC/SRO 3 I-ATC/SRO PZR Level Temp compensating instrument fails low 4 C-BOP/SRO (TS) Isolable steam leak - Loss of AFP 2 5 I-ATC/SRO Loss of ICS DC - trip reactor 6 C-BOP/SRO Loss of AFP 1 - start MDFP 7 M- All Loss of all Feedwater - initiate MU/HPI/PORV cooling
- (N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor
DAVIS-BESSE 2016 NRC SCENARIO 3 The crew will take the watch with power at 100% power and no activities planned. The first event will be triggered resulting in the RCS pressure instrument selected for NNI failing low. The crew will implement DB-OP-02513, Pressurizer System Abnormal Operation, for failure of pressure input to heater. Manual control of heaters will be required due to input pressure signal failed low. The pressure input to NNI will be swapped to the non-faulted signal IAW DB-OP-06403, RPS and NNI Operating Procedure. Heater controls will then be returned to automatic control. The Unit Supervisor will enter applicable Technical Specifications (3.3.1) for the pressure instrument failure and direct tripping or bypassing the RPS channel with failed instrument within one hour (TS). On the Lead Evaluators discretion the scenario will proceed to event 2.
Event 2 will result in a HPFW Heater 1-6 tube leak. The crew will diagnose in response to annunciator 13-5-E, HPFW Htr 1-5 Lvl, using alarm procedure DB-OP-02013, Condensate Feedwater Alarm Panel 13 Annunciators. Power will be lowered to 95%
using DB-OP-02504, Rapid Shutdown. The #1 HPFW Heaters will be bypassed and isolated using DB-OP-06229, High Pressure Feedwater Heater System Operation. Once HPFW Heater Train 1 is bypassed/ isolated the scenario can proceed to the next event.
When event 3 is cued by the Lead Evaluator the Pressurizer Temperature Transmitter TE RC15-1 will fail low resulting in lowering pressurizer level indication (temperature compensated) and increased makeup flow as MU32, Makeup Flow Controller, responds to the failure. The crew will diagnose the failure and enter abnormal procedure DB-OP-02513, Pressurizer System Abnormal Operations, and place MU32 in hand to control pressurizer level. Alternate temperature input to pressurizer temperature (TE RC15-2) will be verified functional and selected, then MU32 can be returned to automatic control.
If pressurizer level exceeds 228 inches compensated (147 inches uncompensated) during the failure then Technical Specification 3.4.9 will be entered for the Pressurizer.
Event 4 will be initiated by the Lead Evaluator resulting in an isolable steam leak and the loss of #2 AFP. The crew will respond to annunciator 12-2-A, SG 1 to AFP 2 Mn Stm Press Lo, and implement abnormal procedure DB-OP-02525, Steam Leaks. The steam leak will be determined to be in AFPT Room 2, and attachment 1 of DB-OP-02525 will be used to isolate the steam leak. The Unit Supervisor will review applicable Technical Specifications and enter 3.7.5 Condition A and B for Inoperable Steam Supply (TS).
At the Lead Evaluator cue event 5 will be initiated which will trigger events 6 and 7. A loss of ICS DC power will occur requiring the crew to implement immediate actions of DB-OP-02532 and trip the reactor and manually initiate and isolate SFRCS. The crew will then implement the Emergency Procedure DB-OP-02000. AFP 1 will not come up to proper speed due to a governor problem and the BOP will start the MDFP per Specific Rule 4 of DB-OP-02000. The MDFP will trip after two minutes resulting in a loss of all feedwater. The ATC will attempt to start the standby makeup pump but it will fail to start.
With only one makeup pump in service the crew will commence aligning for MU/HPI/PORV cooling per attachment 4 (CT-14, Establish MU/HPI Cooling). When the PORV is opened Adequate Subcooling Margin (SCM) will be lost and all Reactor Coolant Pumps will be tripped (CT-1, Trip All RCPs). At the Lead Evaluator discretion the scenario will be terminated.
Indications Available:
- 4-4-C HOT LEG PRESS LO
- 5-3-J RPS RC PRESS-TEMP TRIP
- All Pressurizer Heater Banks are on
- RCS Wide Range (actual) Pressure is rising Crew Recognize failure low of RPS pressure input to PZR heaters with indications available listed above SRO Implement DB-OP-02513, Pressurizer System Abnormal Operation, for failure of pressure input to heaters ATC Manually control Pressurizer Heaters and Spray to maintain required RCS Pressure (2105 to 2205) - Heaters will be ON in auto Place the following Pressurizer Heaters in OFF
- HIS RC2-2, Bank 2
- HIS RC2-3, Bank 3
- HIS RC2-4, Bank 4 ATC
- HIS RC2A, Essen Bank 1
- HIS RC2B, Essen Bank 2 Place PIC RC2 Bank 1 in MANUAL and maintain RCS pressure by adjusting the output. Manually energize other heater banks if needed to maintain pressure band SRO Refer to TS 3.4.1, RCS Pressure, Temperature and Flow DNB Limits - entry into Tech Spec is not required for this failure.
BOP Exchange RCS pressure input to NNI from RPS, REFER TO DB-OP-06403, RPS and NI Operating procedure Obtains Key 33 from SM key locker and Opens RPS Channel 2 cabinet.
BOP Remove the cap on the selection panel for the alternate RC PRESSURE NNI receptacle in RPS Channel 2.
Disconnect the amphenol connector from the RC PRESSURE NNI subassembly and reconnect the amphenol connector to the alternate RC PRESSURE NNI Receptacle.
Cap the open RC PRESSURE NNI receptacle.
Return PZR heaters to Auto Control
- HIS RC2-2, Bank 2, in AUTO + BASE
- HIS RC2-3, Bank 3, in AUTO
- HIS RC2-4, Bank 4, in AUTO ATC
- HIS RC2A, Essen Bank 1, in AUTO
- HIS RC2B, Essen Bank 2, in AUTO Place PIC RC2 Bank 1 in AUTO Circle the RPS Channel now supplying the input signal to the NNI.
BOP RPS Channel 2 is now supplying.
REFER to TS 3.3.1. Declare RPS Channel 1 Inoperable, Functions 3, 4, and 5.
SRO Enter TS 3.3.1 Condition A Trip or Bypass within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> NOTE: RPS Channel 1 is already tripped SM IF necessary, Role-play SM and direct crew to leave RPS channel in the tripped condition while I&C evaluates as found CUE conditions.
On Lead Evaluators discretion, proceed to Event 2
Indications Available:
- L454, HP HEATER 1-4 HIGH LEVEL ALARM (Computer Point)
- 14-5-C, ICS HI LOAD LIMIT
- 14-6 D, ICS IN TRACK Implement DB-OP-02013, Condensate Feedwater Alarm Panel Crew 13 Annunciators for annunciator 13-6-E ATC Maintain Power at or below 100%
NOTE: Crew may enter DB-OP-02526 Primary to Secondary Heat Transfer Upsets to stabilize the plant.
Check the computer point alarm list to determine whether a high or low level exists:
Crew
- L454, HP HEATER 1-4 HIGH LEVEL ALARM Determine level is high.
Direct EO to locally verify HD 291A, FW HEATER 1-4 EMERGENCY DRAIN CONTROL VALVE, is throttled.
BOP Direct EO to locally verify HD 291B, FW HEATER 1-4 NORMAL DRAIN CONTROL VALVE, is open.
After 2 minutes role-play EO and report:
HD 291A, FW HEATER 1-4 EMERGENCY DRAIN CONTROL VALVE, is throttled OPEN BOOTH HD 291B, FW HEATER 1-4 NORMAL DRAIN CONTROL CUE VALVE, is FULL OPEN Level in 1-4 HTR is 11.8 Level in 1-5 HTR is 11.4 Level in 1-6 HTR is 10.5 NOTE: Comparison of normal drain flows may help determine if heater drain flow is abnormal. Normal drain flows at 100% power are approximately 1400 KPPH.
Crew may confirm tube leak in heater by monitoring for Crew abnormally high or excessive heater draining.
- a. Compare normal drain flow computer points.
~1,700 KPPH
~1,400 KPPH Crew Determine HPFW Heater Train 1 has a tube leak Refer to DB-OP-06229, High Pressure Feedwater Heater System SRO Operation. Routes to Section 5.1, HPFW Heater Tube Rupture Train 1 NOTE: Bypassing HPFW Heaters will result in Feedwater Flow and Temperature transients including Deaerator levels. Minimizing plant power levels prior to bypassing will reduce the potential for a plant trip.
Directs a plant power reduction to 95 percent - A single HPFW Train will be removed from service. DB-OP-02504, Rapid SRO Shutdown, may be entered but is not referenced by the alarm procedure Begin plant shutdown using US provided setpoints:
- Set rate of change ATC
- Select target Power
- Monitor Power Crew Monitor plant shutdown to 95%
Isolate feedwater to HPFW Heater Train 1 by simultaneously performing the following:
- Dispatch Equipment Operator to local stop pushbutton for FW448
- Throttle open FW 460, HP HTR TRAINS BYPASS, using HIS 460 to maintain Train 2 flow, as read on FI 581, BOP HPFW HTR GROUP 2 FW FLOW, approximately one half the total Feedwater flow. FI 581 flow equals either 428 or 438 flow MFP 1/MFP 2 flow indicators
Report EO on station at FW448 BOOTH CUE If necessary, role play EO and stop motion of FW448 as directed.
Close ES 2014, EXT STM TO HP HTRS ISO TRAIN 1, using HIS BOP 2014.
Verify ES 252, FEEDWATER HEATER - EXT STM LINE DRAINS BOP TRAIN 1, 1-6, is open, using HIS 252.
Direct EO to locally isolate HPFW Heater Train 1 per DB-OP-BOP 06229, Step 5.1.7.
BOOTH Locally isolate HPFW Heater Train 1 or remove malfunction CUE and isolate the MSRs.
NOTE: The reliefs for the HPFW Heaters relieve to the TPCW Low Level Tank. This may result in elevated TPCW temperatures and levels.
Monitor TPCW System performance. REFER TO DB-OP-06263, Crew Turbine Plant Cooling Water System, as necessary.
BOOTH If necessary, Role-play the SM and report Alignment of the CUE 50# header is NOT required
On Lead Evaluators discretion, proceed to Event 3 Indications Available:
- 2-4-C, MU FLOW HI TRN 2
- 4-2-E, PZR LVL LO Respond to annunciator 4-2-E, identify PZR temperature ATC indication is failed low Implement DB-OP-02513, Pressurizer System Abnormal SRO Operation, Section 4.6, Failure of Selected Pressurizer Level or Temperature Instruments.
ATC Place MU32, RCS Makeup valve, in HAND using LICRC14 ATC Adjust MU32 to obtain desired Makeup flow or PZR level -
Discuss with SRO and determine level band for manual control SRO Set Pressurizer level control band based on uncompensated level
(~135-145 inches).
ATC Compare PZR Temperature Instruments, identify selected TE has failed (TTRC15-1/TTRC15-2)
SRO Refer to DB-OP-06407, Non Nuclear Instrument Operating Procedure, for transferring input ATC Select good input to HSRC15
- Place HIS RC 15 to the TT RC 15-2 position ATC Place MU32 in AUTO SRO Review TS 3.4.9, Pressurizer, Condition A for high level, if Pressurizer level reached 228 inches or uncompensated level greater than 147 inches.
On Lead Evaluators discretion, proceed to Event 4
Indications Available:
- Fire alarms Recognize a steam leak in AFPT Room 2 Crew
- Lower power as needed to maintain 100% (limit of 95% not once HPFW Train 1 is isolated and bypassed, though crew may maintain 95% unless told otherwise)
Direct Shift Manager to refer to RA-EP-01500, Emergency SRO Classification BOP Determine the leak location is in AFPT Room 2 based on annunciator 12-2-A, P012, and/or fire alarms SRO Direct BOP to perform Attachment 1, Isolation of Main Steam Line 1 to AFPT 2 Leak BOP Attempt to isolate the leak as follows:
- Close MS 107A
- Verify MS 107 is closed
- Verify MS 106 is closed BOP Recognize annunciator 12-2-A is extinguished - Notify the US that the leak is isolated and to GO TO Attachment 8 for continued operation SRO Go to Attachment 8, Evaluation for Continued Operation SRO Request Equipment Operator(s) open breakers for MS107 (BF1124) and MS107A (BF1188)
SRO Direct Maintenance/Engineering to investigate the area for extent of damage
Review Technical Specification for AFP 2 inoperable - Declare SRO AFP 2 Inoperable. Enter TS 3.7.5, Condition B and direct energize blue TS Operability light SRO Request Radiation Protection survey the area SRO Direct Shift Manager to review for Notification requirements, and review for Classification per RA-EP-01500, Emergency Classification:
On Lead Evaluators discretion, proceed to Event 5, 6, and 7
Indications Available:
- ICS IN TRACK (14-6-D)
- ICS 24 VDC BUS TRIP (14-1-C)
- ICS H/A Station Lights OFF
- MDFP Trip (10-1-H)
Recognize a loss of ICS DC Power
- ICS IN TRACK (14-6-D)
Crew
- ICS 24 VDC BUS TRIP (14-1-C)
ICS H/A Station Lights OFF Perform immediate actions
- Trip the Reactor ATC
- Verify power decreasing
- Trip the turbine ATC Manually actuate initiate & isolation of SFRCS SRO Implement DB-OP-02000 Verify immediate actions:
- Trip the Reactor SRO/ATC
- Verify power decreasing
- Trip the turbine
- Verify all Turbine Stop Valves OR Control Valves are closed Crew Check for Specific Rule or Symptom Direction Implement Specific Rule 4 for a loss of both AFPs (AFP 1 does BOP not reach sufficient speed/discharge pressure to provide flow)
Enable MDFP Discharge Valves BOP
- HIS 6459
- HIS6460 Close both MDFP discharge valves BOP
- LIC 6459
- LIC 6460 Start the MDFP BOP NOTE: (After 2 minutes the MDFP will trip)
Crew Recognize the MDFP trips ATC Attempt to start the standby Makeup Pump 1 (fails to start)
SRO Go to Attachment 4 for aligning MU/HPI/PORV Cooling BOP Use Attachment 5 to attempt to restore a source of feedwater
Implement Attachment 8, Place MU/HPI/LPI in Service
- *Start/Verify running both CCW Pumps
- *Start both HPI Pumps
- *Open DH 63
- Transfer MU Pump 1 suction to the BWST- MU6405 - not critical since MUP 1 is not running
- *Transfer MU Pump 2 Suction to the BWST- MU3971
- *Set Pressurizer Level Controller to 100 inches ATC *Place all PZR Heaters in OFF ATC Lock MU Pump suctions on the BWST
- MU 6405 - not critical since MUP 1 is not running
ATC Close MU6407 - not critical since MUP 1 is not running ATC *Close MU6406 ATC Verify RC11 is open ATC *Lock open the PORV Specific Rule 6 check for EDGs running on SFAS initiate:
SRO/ATC
- Check for EDGs running and proper cooling When Adequate SCM is lost (<20ºF):
- Critical Task ATC/BOP * *Trip the remaining running RCP (CT-1)
- *RC4608B
- *RC4608A ATC Open Loop 2 High Point Vents
- *RC4610B
- *RC4610A ATC Open PZR High Point Vents
- *RC200
When MU/HPI/PORV cooling is in progress and at Lead Evaluator discretion the scenario can be terminated
Justification for Critical Tasks A. Establish MU/HPI Cooling (CT-14)
MU/HPI cooling is required to be established immediately when only one makeup pump is available during a loss of all feedwater. Establishing MU/HPI cooling will prevent the RCS pressure from exceeding the shut off head of the HPI pump.
B. Trip All Reactor Coolant Pumps (CT-1)
Subcooling Margin will be lost due opening the PORV for MU/HPI cooling. Specific Rule 2 actions will be taken to stop the remaining RCP in service. Continued RCP operation could lead to fuel clad failure.
SIMULATOR SETUP INFORMATION
- 1. Simulator Setup a) 100% Power b) AFP 1 does not obtain proper speed on start (governor problem) c) MDFP trips 2 minutes after starting d) Makeup Pump 1 fails to start
- 2. Procedures Used by the crew a) DB-OP-02513, PZR System Abnormal Operation b) DB-OP-06403, RPS and Nuclear Instrumentation Systems c) DB-OP-02013, Condensate/Feedwater Alarm Panel 13 d) DB-OP-02526, Primary to Secondary Heat Transfer Upset e) DB-OP-06229, High Pressure Feedwater Heater System f) DB-OP-06407, Non Nuclear Instrument Operating Procedure g) DB-OP-02525, Steam Leaks h) DB-OP- 02532, Loss of NNI/ICS Power i) DB-OP-02000, RPS, SFAS, SFRCS Trip, or Steam Generator Tube Rupture For Simulator Instructor/Communicator a) DB-OP-06229, High Pressure Feedwater Heater System, sect. 5.1 b) DB-OP-06229, High Pressure Feedwater Heater System, Att. 10 c) DB-OP-02525, Steam Leaks, Att. 8
Facility: Davis-Besse Scenario No.: 4 Op Test No.: DB NRC 2016 Examiners: Operators: SRO ATC BOP Initial Conditions:
- 100% power
- Makeup Pump 2 in service Turnover:
- Maintain 100% power Planned:
- Shift Routines Critical tasks: 1. Control SG Pressure (CT-11)
- 2. Control HPI (CT-5)
Event Malf. Event Type* Event No. No. Description 1 C-BOP/SRO Condensate Pump high bearing temperature 2 C-ATC/SRO Makeup Pump trip (TS) 3 C-BOP/SRO Rising condenser pressure - Mechanical Hogger failure 4 C-ATC/SRO Purification Demin isolates R-ATC/SRO 5 SG 2 tube leak (TS) 6 M-ALL SG 2 tube rupture/Turbine Trip/Rx Trip 7 C-BOP/SRO MSR 2nd Stage Reheat valves fail to auto close
- (N)ormal, (R)eactivity, (I)nstrument, (C)omponent, (M)ajor
DAVIS-BESSE 2016 NRC SCENARIO 4 The scenario begins with the plant in Mode 1 and the crew maintaining 100% power.
Condensate Pump 1 will develop a high bearing temperature. Condensate Pump 1 will be shut down and reactor power will be reduced as needed until within the capacity of two condensate pumps.
At the Lead Evaluator cue event 2 will be triggered resulting in the trip of the running Makeup Pump. The SRO will implement DB-OP-02512, Loss of RCS Makeup. The ATC will close MU2B, RCS Letdown isolation, close MU19, Seal Injection isolation, and close MU32, PZR level control valve. The SRO will enter the applicable TS for the Inoperable Makeup Pump (TRM8.1.1). The ATC will start the standby Makeup pump, restore MU and Seal Injection flow, and reestablish Letdown.
When Makeup is restored and Letdown reestablished the Lead Evaluator will cue event 3 resulting in rising condenser pressure. The crew will identify rising pressure from trend recorder data or from receipt of annunciator alarms 15-1-F and/or 15-2-F, Hi/Lo Condenser pressure Hi. The Unit Supervisor will enter abnormal procedure DB-OP-02518, High Condenser Pressure. The Mechanical Hogger will fail to auto start and the BOP will manually start the Mechanical Hogger. Condenser pressure will stabilize at less than 5.0 inches HgA and reactor power reduction to maintain less than or equal to 5.0 HgA will not be required. At Lead Evaluator discretion the scenario will proceed to the 4th event.
Event 4 will result in MU10B, Mixed Bed 2 Letdown Inlet, failing closed isolating the Letdown flow path. The crew will diagnose the loss of Letdown using indication of no Letdown flow and annunciator 2-2-A, Letdown Pressure High. The crew will refer to alarm procedure DB-OP-02002 and verify close MU4, Pressure Reducing Valve, and MU6, Letdown Flow Control Valve. Proper lineup will be checked and MU10B identified as being closed. MU10B will fail to open if attempted and Letdown will be reestablished by placing #1 demineralizer in service. The Unit Supervisor may elect to enter abnormal procedure DB-OP-02512, Makeup and Purification System Malfunctions, for the loss of Letdown flow path if not diagnosed and corrected in a timely manner using the alarm procedure.
When Letdown is restored the Lead Evaluator will cue event 5 resulting in indications of a tube leak in #2 Steam Generator (approximately 25 gpm). The crew will respond to annunciator 12-1-B, MN STM LINE 2 RAD HI, in accordance with DB-OP-06012, STM GEN/SFRCS Alarm Panel 12 Annunciator and then enter DB-OP-02531, STEAM GENERATOR TUBE LEAK. The crew will evaluate the SG leakage and determine the leak rate is in excess of T.S. 3.4.13 and start a rapid shutdown (TS).
When a rapid shutdown is in progress event 6 will be triggered which will increase the tube leak to a tube rupture at approximately 300 gpm. The crew will identify with calculations/indications that the tube leak has degraded to a tube rupture at greater than 50 gpm. The Unit Supervisor will implement the Emergency Procedure by routing to section 8 for Steam Generator Tube Rupture. Attachment 8, Place MU/HPI/LPI in Service, will be performed (CT-5, Control HPI). The reactor will trip at approximately 65% power when the turbine will trip due to an electrical fault.
Event 7 will be automatically triggered with the MSR Second Stage Reheat Valves failing to auto close. The crew will identify indications of Overcooling and the Unit Supervisor will route to section 7 for Overcooling. Implementation of attachment 20, Isolate or Control Potential Source of Overcooling, should identify the MSR Second Stage Reheat Valves failing to auto close. MS314 and 199, MSR Second Stage Reheat Valves, will close if attempt to manually close is initiated. The crew may manually initiate and isolate SFRCS to terminate the overcooling. The crew will control steam generator pressure to commence a cooldown and maintain minimize subcooling margin to minimize stresses on the faulted generator tubes (CT-11, Control SG Pressures). At the Lead Evaluator discretion the scenario will be terminated.
Indications Available:
Crew Recognize Condensate Pump 1 has high bearing temperature ATC/BOP Dispatch operator to Condensate Pump 1 Booth After 2 minutes - Role play as operator and report Motor Cue Bearing feels hotter than usual Monitor Condensate Pump 1 bearing temperature (T176) and ATC/BOP refer to Motor Temperature Limit aid SRO may refer to DB-OP-06221, Condensate System - Limit and SRO Precaution 2.2.1- pump trip guidance is also provided on Motor Temperature Limit aid Crew Recognize trip criteria is 212°F- Identify to be above 212°F SRO Direct trip of Condensate Pump 1 BOP Stop Condensate Pump 1 using control switch HIS558 Reduce Reactor Power to within the capacity of two condensate pumps (7.0 MPPH) as necessary
- Input target power into ULD ATC
- Rate of change may be increased NOTE: Slight reduction of power needed to reduce condensate flow to less than 7.0 MPPH. DB-OP-02504, Rapid Shutdown may be used to direct shutdown.
On Lead Evaluators discretion, proceed to Event 2
Indications Available:
- Annunciator 6-5-C SEAL INJ FLOW LO
- Annunciator 6-6-C SEAL INJ TOTAL FLOW
- Makeup Pump red RUN light OFF
- Zero Makeup flow
- MU32, Pressurizer Level Control Opening
- MU19, RCP Seal Injection Flow Control Opening Recognize a loss of running RCS Makeup Pump using indication Crew available listed above Implement DB-OP-02512, Makeup and Purification System SRO Malfunctions, for a loss of RCS Makeup Pump Isolate Letdown using MU 2B ATC
- Depress CLOSE on HISMU2B ATC/BOP Dispatch operators to investigate pump trip Verify CCW is being supplied to the RCPs using Attachment 1, Verification Of CCW Flow To Reactor Coolant Pumps
- Verify a CCW Pump in service
- Verify Open CC5095, Supply
- Verify Open CC5097, CTMT BLDG Return Open
- Verify Open CC1411A
- Verify Open CC1411B
- Verify Open CC1407A ATC/BOP
- Verify Open CC1407B Verify Seal Cooling CCW Return flow path is available
- RCP 1-1 CC4100 Open
- RCP 1-2 CC4200 Open
- RCP 2-1 CC4300 Open
- RCP 2-2 CC4400 Open Check Annunciator Alarm 6-5-B, SEAL CCW FLOW LOW is extinguished Notify SRO CCW flow is available to the Reactor Coolant pumps Monitor Pressurizer level and compare to curve CC 4.3 - Anytime ATC Pressurizer Level is less than 160 inches, trip the reactor and go to DB-OP-02000 ATC Isolate RCP Seal Injection by closing MU19 using FICMU19
Place MU32 in Hand AND close MU32 using LICMU14 to isolate ATC the normal Makeup flowpath Refer to DB-OP-02515, Reactor Coolant Pump and Motor SRO Abnormal Operation Crew Monitor RCP Seal parameters BOP/ATC Maintain Tave constant Refer to TRM 8.1.1, Boration Systems - Operating SRO Enter TRM 8.1.1, Nonconformance A Notify the Shift Manager to perform event notifications and Fleet SRO Reporting updates Booth Role play if asked to investigate Makeup Pump 2 trip - report 50/51 relay target on MUP 2 breaker AD105 Cue Role play if asked no local pump problems observed Verify Makeup Pump did not indicate cavitation
- No erratic amps, No erratic flow ATC
- No erratic discharge pressure
- Makeup pump did not empty Crew Verify operator on station to monitor standby makeup pump start Start Makeup Pump 1 ATC
- Start Makeup Pump 1 oil pumps
- Start Makeup Pump 1 Booth Role play as equipment Operator and report when stationed Cue at MUP and proper operation of MUP 1 Restore Makeup flow using Attachment 4
- Verify MU6421 Closed ATC
- Verify MU6422 Open
- Throttle as needed and place MU32 in Automatic
NOTE: Attachments 4 and 5 can be performed in either order or in parallel Restore Seal Injection flow using Attachment 5
- Verify MU19 closed
- Verify MU66A through D open
- Verify MU6408 Open ATC
- Verify MU6409 Open
- Gradually over 2 minutes open MU19 to establish 12-15 gpm seal inject flow (minimum 3 gpm to any RCP)
Restore letdown - Open MU2B ATC Depress OPEN on HISMU2B When 10 minutes has elapsed raise seal injection flow to 20-25 ATC gpm NOTE: Not necessary to complete to proceed to next event When 10 minutes has elapsed raise seal injection flow to 32-36 ATC gpm and place FICMU19 in Auto NOTE: Not necessary to complete to proceed to next event On Lead Evaluators discretion, proceed to Event 3
Indications Available:
- Annunciator 15-1-F HP CNDSR HI
- Annunciator 15-2-F LP CNDSR HI
- Annunciator 14-2-F ICS ULD TRBL
- HP PR 530 rising (trend recorder)
- LP-PR 541 rising (trend recorder)
- Lowering MW Crew Recognize indications of slowly increasing condenser pressure (available indications listed above)
SRO Implement DB-OP-02518, High Condenser Pressure Reduce Power as needed to maintain less than or equal to 7.0 ATC MPPH condensate flow (limit for two Cond Pumps in service)
Verify the Mechanical Hogger Starts at 4.5 inches HgA LP Condenser (Auto start is failed)
- Position switch HIS1005 to START (Condenser pressure will stop increasing and slowly improve)
Reduce Reactor Power as needed to maintain Condenser ATC pressure less than or equal to 5.0 inches HgA NOTE: Should not be needed unless slow to start hogger BOP Verify proper Circ Water Pump operation BOP Verify Condenser Vacuum Breakers are Closed (HIS634)
BOP Check proper operation of Gland Sealing Steam system SRO Request assistance to determine the cause (Attachment 1)
SRO Notify the Shift Manager to refer to Notification requirements On Lead Evaluators discretion, proceed to Event 4
Indications Available:
- Zero Letdown flow or identification of relief lifting to RCDT
- Annunciator 2-2-A LETDOWN PRESS HI Recognize a loss of the Letdown flowpath:
Crew
- Zero Letdown flow/identify relief lifting to RCDT
- 2-2-A LETDOWN PRESS HI Refer to DB-OP-02002, Letdown/Makeup Alarm Panel 2 ATC Annunciators NOTE: If diagnosis is slow the SRO may implement abnormal procedure DB-OP-02512, Makeup and Purification System Malfunctions, for the loss of Letdown flowpath ATC Verify MU 4, Pressure Reducing Valve, is closed ATC Verify MU 6, Letdown Flow Control Valve, is closed using HCMU6 Check for correct valve lineup in the Letdown line ATC Recognize MU10B is closed SRO Direct attempting to open MU10B ATC Attempt to Open MU10B using HISMU10B (will remain failed)
SRO Direct placing another demin in service or bypassing demins If necessary - Shift Manager directs placing #1 Demin in CUE service and restore Letdown ATC Depress Open on HISMU10A ATC Throttle open MU6 using HCMU6 to restore flow to 70 gpm Verify PSV1890 is not lifting/leaking by observing RCDT level ATC/BOP (LI1721 or trend pen) - Alarm procedure action
If Pressurizer level reaches 228 inches then TS 3.4.9 will need to SRO be entered and restored within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.
When Letdown has been restored proceed to Event 5
Indications Available:
- Annunciator 9-4-A VAC SYS DISCH RAD HI
- Annunciator 12-1-B MN STM LINE 2 RAD HI
- Increasing Makeup flow Crew Recognize indications of a SG tube leak
- Annunciator 9-4-A VAC SYS DISCH RAD HI
- Annunciator 12-1-B MN STM LINE 2 RAD HI
- Increasing Makeup flow SRO Route to DB-OP-02531, Steam Generator Tube Leak Calculate a leak rate (~25 gpm). REFER to Attachment 1, Steam ATC Generator Tube Leak Calculation Determine SG 2 has the tube leak (~25 gpm)
Crew Note: If >50 gpm is calculated the crew will route to OP2000 Notify SM to refer to EP Classification, Offsite Dose assessment, SRO and notification requirements Refer to TS 3.4.13, RCS Operational Leakage. Enter Condition B SRO for primary to secondary leakage SM IF needed, Role-play SM and direct to lower power at 5%/min.
CUE Direct a plant shutdown per DB-OP-02504, Rapid Shutdown, SRO Attachment 1, Power Reduction Actions ICS Full Automatic Begin plant shutdown
- Set rate of change as directed ATC
- Select target Power - 20% RTP for Low level limits
- Monitor Power SRO Direct BOP to perform Attachment 6, BOP Actions BOP Direct an EO to remove AFPT Main Steam minimum flow lines
Direct an EO to coordinate control of Moisture Separator Reheat BOP RSLLVs at ~675 MWe (refer to Attachment 9)
SRO Notify EOs to commence Attachment 15, Field Actions SRO Notify Load Dispatcher Notify Chemistry to monitor polisher operation and sample for SRO isotopic analysis of iodine per TS 3.4.16 SRO Notify SM to complete required notifications At approximately 80% power event 6 and 7 will auto trigger
Indications Available:
- Pressurizer level decreasing
- Increasing Makeup flow Recognize increase in leak rate indicates a SG Tube Rupture, Crew (greater than 50 gpm), using PZR level , Makeup Flow , and/or computer leak rate program.
Go to DB-OP-02000, RPS SFAS, SFRCS Trip, or SG Tube Rupture, Section 8 SRO NOTE: Turbine will trip due to electrical fault resulting in Rx trip at approximately 65% power Crew Recognize Reactor Trip (Turbine trip at approximately 65%)
Perform DB-OP-02000 Immediate Actions
- Manually trip the reactor ATC
- Verify power decreasing in the intermediate range
- Manually trip the turbine Verify immediate actions
- Verify Reactor is tripped SRO/ATC
- Verify power decreasing in the intermediate range
- Manually trip the turbine
- Verify all 4 Stop Valves or Control Valves are closed Crew Check for Specific Rule implementation Check for Symptom Mitigation section implementation Crew
Implement Attachment 8, Place MU/HPI/LPI in Service
- Start/Verify running both CCW Pumps
- Start/Verify running both HPI Pumps
- Start both LPI Pumps ATC/BOP
- Open DH 64 and DH 63
- Transfer MU Pump suctions to the BWST Set Pressurizer level to 100 Inches NOTE: Attachment 8 may be started when Tube Rupture is identified prior to reactor trip (OP2000 section 8)
Two handed operation of HP2A-2D is authorized If Pressurizer Level is less than 40 inches:
- Lock MU Pump suctions on the BWST ATC
- Isolate Letdown Verify Pressurizer heaters are off Implement Attachment 20, Isolate or Control Potential Source of BOP Overcooling Terminate the overcooling:
- *Manually Initiate and Isolate SFRCS (Auto Initiate/Isolate is failed)
If the MSR Second Stage Reheat valves were isolated:
- Check for entry into PTS If SFRCS was actuated:
- Verify proper SFRCS actuation
- Control AVVs to maintain RCS temperature constant or slowly decreasing
- Verify proper SG level control
- Check for entry into PTS SRO Route to Section 4.0 Supplemental Actions SRO Route to Section 8.0 step 8.19
ATC Verify Attachment 8 is complete If Pressurizer Level is less than 40 inches:
- Lock MU Pump suctions on the BWST ATC
- Isolate Letdown using MU2B
- Verify Pressurizer heaters are off ATC Verify Pressurizer level controller set at 100 inches Verify DB-OP-02531 Attachments are in progress
- Direct Chemistry to perform Attachment 2 SRO
- Direct Radiation Protection to perform Attachment 3
- Direct an Equipment Operator/Field Supervisor to perform Attachment 4 If the Aux Boiler is running then direct an Equipment BOP Operator/Field Supervisor to transfer Aux Steam and Gland Steam to the Aux Boiler ATC Turn off all Pressurizer heaters SRO Route to step 8.40 Use Pressurizer Spray to reduce RCS pressure to Minimize ATC Subcooling Margin ATC Throttle High Pressure Injection
- Control Pressurizer level by throttling MU and HPI flows as
- Critical pressure is reduced to prevent overfilling the pressurizer:
Task (CT-5)
- Throttle/close HP 2A, HP 2B, HP 2C and HP 2D as needed to prevent overfilling the pressurizer as RCS pressure is reduced EAL SU7 Unusual event based on leak greater than 10 gpm or FA1 Alert based on greater than 250 gpm leak At Lead Evaluator discretion the scenario can be terminated
Justification for Critical Tasks A. Control SG Pressure (CT-11)
Control of SG Pressure lowering due to overcooling will be accomplished by recognizing the cause to be MSR Reheat Low Load Valves failing to auto close and manually closing, or Initiating and Isolating SFRCS (auto initiate/isolate is failed).
B. Control HPI (CT-5)
Due to the loss of inventory through the Steam Generator tube rupture, High Pressure Injection will be placed in service to inject water to maintain Pressurizer level. When depressurizing the RCS, control per specific rule 3 will be required and HPI 2A-2D throttled and or closed to prevent overfilling the pressurizer.
SIMULATOR SETUP INFORMATION
- 1. Simulator Setup a) 100% Power b) Makeup Pump 2 in service c) Mechanical Hogger failure to auto start d) MU10B fails to open when triggered closed e) Tube leak increases to a rupture (300 gpm) at approximately 80%
f) SFRCS Auto Initiate/Isolate failed g) Reactor Trip due to Turbine Trip (generator fault) at 65% power h) MSR 2nd Stage Reheat Valves fail to auto close
- 2. Procedures Used by the crew a) DB-OP-06221, Condensate System b) DB-OP-02504, Rapid Shutdown c) DB-OP-02512, Makeup and Purification System Malfunctions d) DB-OP-02518, High Condenser Pressure e) DB-OP-02002, Letdown/Makeup Alarm Panel 2 f) DB-OP-02531, Steam Generator Tube Leak g) DB-OP-02504, Rapid Shutdown h) DB-OP-02000, RPS, SFAS, SFRCS Trip, or Steam Generator Tube Rupture For Simulator Instructor/Communicator a) DB-OP-06221, Condensate System, sect. 3.8 b) DB-OP-06006, MU and Purification System, section 3.2 c) DB-OP-02504, Rapid Shutdown, Att. 6 (BOP actions)