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Unit Two is operating at power when the following indications and alarms are noted:
Pump B Seal Staging Flow Hi/Lo (A-07 5-5) alarms
Outer Sear Leakage Flow Detection Hi (A-07 4-5) has not alarmed
Recirc Pump 2B seal #1 pressure indicates 1050 psig
Recirc Pump 2B seal #2 pressure indicates 900 psig
An AO reports that Recirc Pump 2B seal staging flow is 1.8 gpm
What failure has occurred, and when is it recommended that the pump be shutdown?
A. seal #1 failure, immediately.
B. seal #2 failure, immediately.
C. seal #1 failure, within 72 hours.
D. seal #2 failure, within 72 hours.
C. seal #1 failure, within 72 hours.
Seal #1 failure indicated by rise in seal #2 pressure coupled with high seal staging flow alarm. High seal staging alarm setpoint is 1.3 gpm (APP A-07 5-5). Seal #2 failure indicated by drop in #2 sear pressure coupled with outer seal leakage high alarm. OP-02 (3.11) recommends that for a sudden rise in seal pressure above 810 psig, the pump not be operated more than 72 hours and should be shutdown at 980 psig.
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Unit Two was operating at power when a trip of BOP bus 2B required the operator to insert a manual Reactor scram. Shortly following the scram, the following indications are observed:
Recirc pump 2A #1 seal pressure is 1000 psig
Recirc pump 2A #2 seal pressure is 1000 psig
Recirc pump 2B #1 seal pressure is 100 psig
Recirc pump 2B #2 seal pressure is 50 psig
Drywell pressure is 1.2 psig, rising
Average drywell temperature is 145°F, rising
What operator action is required? Vent the drywell per:
A. OP·10 and isolate Recirc pump 2A per OP-02.
B. OP·10 and isolate Recirc pump 2B per OP·02.
C. SEP·10 and isolate Recirc pump 2A per Op·02.
D. SEP·10 and isolate Recirc pump 2B per OP-02.
B. OP·10 and isolate Recirc pump 2B per OP·02.
Indications are of a dual recirc pump seal failure on pump B (pump “A” indications normal for a tripped pump). AOP-14.0 directs venting the drywell per OP-10 and securing and isolating the pump per OP·02 (pump already tripped). SEP-10 would only be used if directed by PCCP. No entry condition exists for PCCP at this time.
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Unit Two is in Mode 1, with Recirculation Pump 2B only in service. Preparations are being made to start Recirculation Pump 2A. Plant conditions:
Reactor pressure 985 psig
Bottom head drain temp 395°F
Recirc loop A temp 476°F
Recirc loop B temp 522°F
Recirc loop B flow 24,000 gpm
May Recirculation Pump 2A be started?
No, the DT between the coolant in the dome and bottom head is excessive.
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Unit 1 is operating at 90% power. RFP “A” just tripped and RPV level lowered to 175 inches before stabilizing.
The RO observes the following indications:
RPV Water level 178 inches rising slowly
TOTAL CORE FLOW lowering
RECIRC FLOW A LIMIT APP A-06 3-2 lit
RECIRC LOOP A FLOW 52% lowering
RECIRC LOOP B FLOW 82% steady
Valid core flow indication is available from the process computer and no other equipment out of service.
What action is required?
A. Lock the scoop tube of the “A” Recirc MG Set.
B. Reduce the “B” Recirc pump speed manually to 28%.
C. Reduce the “B” Recirc pump speed manually to 40%.
D. Reduce the “B” Recirc pump speed manually to 45%.
C. Reduce the “B” Recirc pump speed manually to 40%.
- · 0OI-01.02 section 5.10.7: if auto doesn’t happen, make it happen
- · APP-A-06 3-2: 182”; A or B > 16.4% - limiter #2 (~42%)
- · 0AOP-23: if auto (runback) didn’t happen, manually reduce to 40%
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Unit 2 is operating at 96% power when Recirculation Pump 2A trips resulting in the following conditions:
Total Core Flow (P603) 33.3 Mlbm/hr
Total Core Flow (U2CPWTCF) 33.2 Mlbm/hr
Indicated Core Plate DP (B017) 5.0 psid
APRMs 52%
Indications of THI None
OPRM System INOPERABLE
Determine the region of the Power/Flow Map where the plant is operating AND determine the required operator action.
A. REGION A, inserting a manual reactor scram is required.
B. REGION B, inserting a manual reactor scram is required.
C. REGION A, insert control rods or raise core flow to exit the region.
D. REGION B, insert control rods or raise core flow to exit the region.
D. REGION B, insert control rods or raise core flow to exit the region.
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Unit 1 was initially at 100% power when an unexplained decrease in reactor power occurred. The following conditions have been noted:
Generator electrical output decrease
Indicated core flow increase
Core plate differential pressure decrease
Reactor Recirculation Loop “A” indicated flow increase
Reactor Recirculation Loop “B” indicated flow unchanged
What action is required?
A. Immediately scram the reactor.
B. Lock the “A” Reactor Recirculation Pump scoop tube.
C. Perform PT-13.1, Reactor Recirculation Jet Pump Operability
D. Lower the speed of the “A” reactor Recirculation Pump and raise the speed of the “B” Reactor Recirculation Pump as needed to restore power to 100%.
C. Perform PT-13.1, Reactor Recirculation Jet Pump Operability
AOP-4.4 symptoms and Supplementary Actions
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Unit 2 is at 100% power when the PUMP B SEAL STAGING FLOW HI/LO annunciator is received. NO other annunciators are in the alarm condition. You observe Recirc Pump 2B seal #2 pressure lower towards zero with seal #1 pressure stable at 1000 psig. All other indications are normal.
These conditions are indicative of:
A. a failure of seal #1
B. a failure of seal #2
C. plugging of internal restricting orifice #1. D. plugging of internal restricting orifice #2.
C. plugging of internal restricting orifice #1.
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Unit Two is operating at rated pressure. While placing the 2B Recirculation Pump in
service a complete failure of the #1 seal occurs. #1 seal cavity pressure is 1000 psig.
Which one of the following identifies the expected system indications for this failure?
A. #2 seal cavity pressure is 500 psig; PUMP B SEAL STAGING FLOW HI/LO annunciator in alarm
B. #2 seal cavity pressure is 500 psig; OUTER SEAL LEAKAGE FLOW DETECTION HI annunciator in alarm
C. #2 seal cavity pressure is 1000 psig; PUMP B SEAL STAGING FLOW HI/LO annunciator in alarm
D. #2 seal cavity pressure is 1000 psig; OUTER SEAL LEAKAGE FLOW DETECTION HI annunciator in alarm
C. #2 seal cavity pressure is 1000 psig; PUMP B SEAL STAGING FLOW HI/LO annunciator in alarm
Normal seal pressures at rated conditions are 1000 psig for seal #1 and 500 psig for seal #2. A failure of seal #1 will cause seal pressures to equalize at rated pressure of 1000 psig. Seal Staging Flow Hi alarm will be received on a failure of either seal. Outer Seal Leakage Flow Detection Hi alarm requires the #2 seal failure.
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Unit 2 is raising power from 85 to 100% with recirculation flow. As speed of the recirculation pumps is raised the RO notes the following:
Increase in total core flow
Decrease in core plate differential pressure
Increase in recirculation loop flows
The RO should:
A. Monitor jet pump indications, this is indication of a potential jet pump failure.
B. Check the operation of the feedwater heaters; this is indication of a detreased moderator temperature causing increased subcooling to recirculation pumps.
C. Monitor recirculaton pumps speed closely and lock the scoop tube of the pump that continues to increase. This is an indication of a recirculation pump control system failure.
D. Continue with power ascension these indications are normal at high power due to increase in two phase flow.
A. Monitor jet pump indications, this is indication of a potential jet pump failure.
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Unit Two (2) was operating at 90% power when the “A” recirculation pump experienced a SPEED CONTROL SIGNAL FAILURE. It was verified that the cause was not a recirc pump runback and the scoop tube on the “A” recirc pump was locked.
Plant conditions are:
Power 55%
OPRM inoperable
Recirc flow (WTCF) 30 Mlbm/hr
Recirc A speed 28%
Recirc B speed 80%
What action is required?
A. RAISE core flow to >35 Mlbs/hr using the unaffected pump.
B. LOWER core flow to <25 Mlbs/hr using the unaffected pump.
C. INSERT control rods to exit region B of the THI graph.
D. Insert a manual SCRAM and inter EOP-01.
D. Insert a manual SCRAM and enter EOP-01.
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