1. ACADs (08-006) Covered Keywords Components, functions, operation, Auxiliary feedwater, Startup, hot standby, plant cooldown, emergency. Description Supporting Material 4.2.7.15.2.2.15.2.2.10

2. Auxiliary Feedwater System 2

3. Number: AT-1260-PP-Aux Feed Rev: 1 Author: Rob Thomas Date: 05/04/11 Approved: Date: References: 1V-LO-TX-20101 Auxiliary Feed Water System 2. AT-1260-LP-Aux Feed Auxiliary Feedwater System 3

4. OBJECTIVES 1. State the purpose of the Auxiliary Feedwater System. 2. List the major components in the AFW System and state the function of each. 3. Describe the operation of the AFW System during: a. Startup b. Hot standby c. Plant cooldown d. Emergency 4. Describe the normal line-up for the AFW System. 5. List the signals which initiate the automatic starting of the motor-driven and turbine-driven AFW pumps. 4

5. Auxiliary Feedwater System Purpose: Serves as a backup system for feeding steam generators whenever RCS temperature is above 350  F and main feed system is not available. Level must be maintained in SG even during emergency since SG is the reactor's heat sink. 5

6. Components: Two Motor Driven Pumps One Steam Turbine Driven Pump Two Condensate Storage Tanks Associated Piping, Valves, & Controls 6

7. From S/G #1 From S/G #2 To S/G #4 To S/G #1 To S/G #2 To S/G #3 CST #1 CST #2 Pump 001 Pump 002 Pump 003 Auxiliary Feedwater System Motor Driven AFW Pump Turbine Driven AFW Pump 7

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9. MDAFW Pump Each pump is capable of 100% capacity. 630 gpm (including recirculation flow) @1517 psi –Takes suction from one CST –Motors are air cooled Each pump feeds 2 SGs 9

10. MDAFW Pump The pumps may be operated manually or will start automatically upon detected loss of heat sink and loss of power events Automatically started by 1) Low water level in any one SG (2 of 3 coincidence) 2) Both MFPs tripped 3) SI (Safety Injection) 4) Blackout signal 10

11. Motor Driven AFW Pump 11

12. Motor Driven AFW Pump Suction Piping 12

13. TDAFW Pump Power supply is Main Steam pressure upstream of MSIV’s (Loops 1 & 2) Exhaust to atmosphere Apply feedwater to SGs during emergencies when the main feedwater and motor-driven pumps are inoperable Capacity - 1175 gpm (almost twice capacity of MDAFW pump) Aligned to all four SGs Auto started by 2 SGs at low level setpoint (2 of 3 coinc per SG) 13

14. Turbine Driven AFW Pump 14

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17. Condensate Storage Tanks(CST) – Vertical, cylindrical tanks of reinforced concrete with a stainless steel liner – CST #1 normally lined up to provide water to the AFW system (Manual valves) – CST #2 provides an alternate water source 17

18. CST Capacity – Capacity - 480,000 gallons each – All non-safety system consuming CST water take a suction via a standpipe with nozzle level that ensures the minimum water level is maintained available 18

19. CST #1 CST #2 Vacuum Degasifier System Overflow Basin 19

20. AFW Actuation Signal Automatic features - AFW is aligned to be placed in service automatically in the event of an emergency Auxiliary feedwater actuation signal (Motor Driven) SI signal (associated train) Loss of offsite power (blackout) associated train Lo-Lo Level in SG - 38% - 2/4 on 1/4 SG Both SGFPs trip (2/2) 20

21. TDAFW Actuation Signal –Actuating signals Lo-Lo SG water level - 38% - 2/4 on 2/4 steam generators Loss of offsite power (black out on either train) 21

22. Objectives Review 1. State the purpose of the Auxiliary Feedwater System. 2. List the major components in the AFW System and state the function of each. 3. Describe the operation of the AFW System during: a. Startup b. Hot standby c. Plant cooldown d. Emergency 4. Describe the normal line-up for the AFW System. 5. List the signals which initiate the automatic starting of the motor-driven and turbine-driven AFW pumps. 22