Reactor Vessel and Internals

Question 1

LCO 3.3.7 “PAM Instrumentation” requirement

Answer 1

The PAM Instrumentation for each CET quadrant 1, 2, 3, and 4, and reactor vessel water level shall be operable

Question 2

LCO 3.3.7 “PAM Instrumentation” applicability

Answer 2

Modes 1-3

Question 3

What is the purpose/function of the reactor vessel flange inner/outer seals?

Answer 3

Seals the closure head to the vessel interface. Normally the inner seal is pressurized, and the outer seal only sees pressure if the inner seal fails. Seals are hollow with flow passages to allow pressurized fluid to pressurize the seal and assist the sealing force.

Question 4

How does the inner seal leakage detection work?

Answer 4

• At 1500 psig on the inner seal, a control room alarm is received.
• Pressure can be verified locally at a pressure gauge by VHX-4.
• Pressure in this line can be bled off to the PSDT from C-40.

Question 5

How does the outer seal leakage detection work?

Answer 5

• At 120” H2O, a control room alarm is received.

- When the alarm comes in, a solenoid valve auto opens to dump the water to the containment sump.

Question 6

What indications do we have of reactor vessel water level?

Answer 6

• local level glass
• LIA-0105 from loop 1 hot leg has narrow/wide range indication
• LIA-0106 from loop 2 hot leg has only narrow range indication
• RVLMS

Question 7

What are the power supplies to RVLMS?

Answer 7

Y-10/20

Question 8

What does RVLMS indicate?

Answer 8

Water level above the fuel

Question 9

What is required for RVLMS to be operable?

Answer 9

4 of the 8 lights need to be operable (2 upper and 2 lower)

Question 10

How many CETs do we have, and how many are qualified?

Answer 10

43 total CETs, 16 of which are qualified and fed to temperature recorders on C-11A.