EOP Core Concepts Flashcards
What valve position and dp are utilized when feeding with a main feed pump per EOP-2?
10-15% open and 100-300 psid
What is and why do we limit the time the Boric Acid storage tanks are utilized as a charging source?
The time is limited to 30 to 45 minutes to preclude boron precipitation in the PCS.
What are the prioritized sources and pathways for boration?
Through charging pumps and line to PCS.
- Pumped feed to CVCS from BA Tanks provided D-Bus energized.
- Gravity feed to CVCS from BA Tanks provided C-Bus energized. Close Make-up stop, VCT and SIRWT outlets.
- Charging pump suction aligned to SIRWT.
Through HPSI Train 2 if normal charging line not available.
What are the strategies for EOP-3, Station Blackout?
- Minimize PCS inventory losses
- Diagnosis of best option for restoring power
- DG
- Safeguards
- Backfeed (Segreto #1 line best)
- Monitor station battery discharge current & strip loads as necessary
What are the strategies for EOP-6, ESDE?
- Secure AFW to affected SG
- Steam intact SG with witin 50 psid of faulted SG
- Throttle SIAS
- Stabilize PCS temp/press when faulted boils dry
- Secure Containment Spray to preclude RAS
What aux feed pump flow control valves are available to throttle flow in the event of a loss of air?
P-8A & P-8B, CV-0727/CV-0749 are backed up by N2. CV-0736A/CV-0737A fail full open.
Use EOP Supplement 19 for local control of either trains valves if necessary.
What are the benefits of forced circulation?
Due to PTS concerns it is highly desirable to maintain forced circulation. Maintaining forced circulation minimizes the loop delta T, better equalizes loop temperatures, provides Rx head mixing, and provides better pressure control via main sprays.
How do we know conditions in containment are not conducive to H2 formation?
Containment Temp <125F
Containment Pressure < 4 psi
ensure that conditions conducive to hydrogen production are not present.
What is the PCS Tave value of the MSSV lift prevent temperature?
540F
Lift temperature for PCS is 551F.
How much water is used in filling and draining a SG with a tube rupture?
Fill from 30 to 85% uses 13,500 gallons.
When can you reduce containment spray and how do you do it?
If no RAS and Containment Pressure less than 33 psia,
Containment Air Coolers are in Accident Mode, AND
SIS actuated with adequate flow per EOP Supplement 4, THEN:
- With three pumps operating, stop P-54B or P-54C.
- With two pumps operating, close CV-3001 (preferred) by taking HS-3001C to bypass or close CV-3002 by taking HS-3002C to bypass.
- Secure P-54B or P-54C.
What is the criteria for starting a primary coolant pump?
EOP-Supplement 3
- Bus 1A or 1B energized.
- Y01 energized. (Power to bearing temperature and other PCP status indicators.)
- At least one Steam Generator is available for removing heat (feed flow and steam flow) from the PCS.
- Single phase natural circulation has been established for the preceding 20 minutes in the loop selected for the first PCP restart.
- Pressurizer level as corrected in EOP Supplements 9 and 10 is between:
- 42% to 57% and controlled for the first PCP started
- 42% to 85% and controlled for subsequent PCP starts
- Saturation pressure using Pressurizer water phase temperature is greater than the Minimum Pressure for PCP Operation curve for the existing PCS temperature. REFER TO EOP Supplement 1, “Pressure Temperature Limit Curves.”
- Average of Qualified CETs is at least 25F subcooled from EOP Supplement 1, “Pressure Temperature Limit Curves,” “Upper Portion” curve.
- CCW to PCPs has NOT been interrupted longer than ten minutes AND CCW is supplying the selected PCP.
- At least one of the following PCP Controlled Bleedoff paths is OPEN:
- PCP Controlled Bleedoff Stop Valve, CV-2191
- PCP Controlled Bleedoff Isolation Valves:
- CV-2083
- CV-2099
- Technical Specifications LCO 3.4.6 and LCO 3.4.7 limits simultaneous operation of P-50A and P-50B when TC is less than 300F.
- To ensure adequate NPSH for P-50D, the following is recommended:
- P-50D not be the first pump starte and P-50C is operating prior to starting P-50D
- Positive indication of PCP Controlled Bleedoff Flow is evident for the PCP to be started (Panel EC-11 recorders REC-C11-02 and REC-C11-03).
- No more than one seal failed on the selected PCP.
- At least one Oil Lift Pump for the selected PCP is available.
What are the mitigating strategies of EOP-9, Functional Recovery Procedure?
- Reactivity Control
- MVAE
- PCS Inventory Control
- PCS Pressure Control
- PCS/Core Heat Removal
- Containment Isolation
- Maintenance Vital Aux
How do you address containment sump strainer clogging?
If containment floor water level rising with sump level falling then:
IF 3 Containment Spray Pumps are operating, THEN STOP one Containment Spray Pump (P-54B or P-54C preferred.)
THROTTLE HPSI flow to achieve 200 to 250 gpm flow to each
operating train by closing 2 loop isolation valves in each train and throttling the others.
When and how do you secure containment spray?
- Containment Pressure < 3 psia
- Not req’d for ambient cooling
- Not requ’d for HPSI subcooling
- Chemistry determines not needed for Iodine removal or ALL of the following:
- Less than 1 hour since trip
- Less than 1800R/hr on Cont HI Range Gamma
- Cont isolated per Supplement 6
Then Stop spray pumps one at a time and monitor conditions.
If one pump operating, secure pump.
No pumps operating, close valves.
During a LOOP/Station Blackout, what could happen to the low pressure turbine?
No cooling water.
Blowouts could rupture by overpressurizing the condenser.
Close MSIVS, MISIV bypasses and blowdown valves.
What is covered in a GOP-8 Brief?
CRS Covers:
- GOP-8 Precautions and Limitations
- TAVE shall be maintained within 3F of TREF and greater than 525F
- Pressurizer level shall be maintained within 3% of programmed level.
- Pressurizer pressure shall be maintained within 2010 to 2100 psia band.
- Steam Generator levels shall be maintained within 5% of normal level
- Duty Plant Manager Book’s Reactivity Plan
- 24% rate of power reduction
- Group 4 Rods to 127 inches
- Initial 60 gallon boration at 20 GPM. No flush. Additional will be in 20 gallon descrete borations.
NCOR Covers:
- Covers approximate amount of boron and rods for a given power reduction based on contingency reactivity plan in Duty Plant Managers Book.
- SOP-6 Precautions and Limitations (specifically for procedure use and rod deviation limitations)
- Inserting regulating rods does not require procedure to be in hand or place kept
- Rods will be aligned to with 2 inches of others in the group every 33 inches
- VERIFY that 78.5 to 81.5 inches exist between rod groups which are
being inserted simultaneously.
NCOT Covers:
- Blow down flow rates per SOP-7
Within EOP-8, Station Blackout, how long do you have to verify Station Battery discharge rate is within the limits of EOP Supplement 7 or 8? What time frame bounds the load shed test to provide 8 hours of battery?
Within 30 minutes.
Load shedding is expected to occur within 1-2 hours. So 2 hours bounds it.
When is a control rod fully inserted?
EOP-1 Basis. Bottom rod indication is lit/in.
Any full length control rod that is above rod bottom indication should be considered not fully inserted.
How do you maximize upper head heat removal during natural circulation?
Maximizing the PCS cooldown rate and maintaining a high PCS pressure within the bounds of EOP Supplement 1 will maximize the reactor vessel upper head heat removal.
What are the strategies for EOP-5, SGTR?
- Secure AFW to affected SG
- Cooldown < 524F to isolate affected SG
- Lower PCS Pressure <940 psi
- Throttle SIAS
- Commence a controlled cooldown
- Monitor isolated SG Pressure
What is the criteria for Hot Leg Injection?
Hot Leg Injection Criteria
- Elapsed time from event initiation is greater than 5.5 hours & shutdown cooling will NOT be in service by 6.5 hours and ANY of the following:
- Less than 25F subcooled or less than minimum subcooling curve for degraded containment.
- PZR level 20%, 40% for degraded
- RVLMS indicates less than 102 inches above fuel alignment plate.