FR-H Series

Question 1

What fission product barriers are challenged during a Loss of Heat Sink?

Answer 1

• Fuel Cladding Barrier
• RCS Barrier

Question 2

Define a Dry S/G

Answer 2

• FR-H.1 FOP: A S/G with < 16% WR (21% adverse) and NO feed flow established.
• Loss of sufficient secondary inventory such that the core heat load shifts to heating the primary RCS inventory.

Question 3

How do you feed a DRY S/G after establishing RCS Bleed and Feed and CETC temperature is RISING?
(Assume there are no NON dry S/G’s available)

Answer 3

• Feed only ONE S/G at max rate until CETC’s temps lower.
• When CETC’s temps lower, check the active S/G for a fault or rupture. If faulted or ruptured, then establish feed flow to an INTACT S/G at < 50k lbm/hr.
• When INTACT S/G WR level > 16% (21% adverse), raise feed to maintain CETC’s lowering AND isolate feed to the faulted/rupture S/G.

Question 4

How do you feed a DRY S/G after establishing RCS Bleed and Feed and CETC temperature is Stable or Lowering?
(Assume there are no NON dry S/G’s available)

Answer 4

Feed only ONE S/G at < 50k lbm/hr until WR level is > 17% (26% adverse) then feed as desired.

Question 5

While performing FR-H.1 when is RCS Bleed and Feed required?

Answer 5

At any time when 2/4 S/G WR levels < 16%

Question 6

What are the requirements for RCS Bleed and Feed to be effective?

Answer 6

Preferred:
- At least ONE CCP running (flow through the BIT)
- One SI pump running.
- Two PZR PORV’s available to open.
Alternate:
- All S/G WR levels > 31%
- One SI pump running.
- Two PZR PORV’s available to open.

Question 7

What are the major action categories for FR-H.1? (Response to Loss of Heat Sink)

Answer 7

• Attempt restoration of feed flow to S/G’s
• Initiate RCS bleed and feed.
• Restore and verify secondary heat sink.
• Terminate RCS bleed and feed.

Question 8

What are the major action categories for FR-H.2? (Response to S/G Overpressure)

Answer 8

• Isolate affected S/G
• Check affected S/G radiation
• Establish blowdown from the affected S/G.

Question 9

For the Heat Sink CSFST, what is the basis for checking NR level in at least one S/G > 13% (28% adverse)?

Answer 9

Determines if level in any S/G is enough to ensure adequate heat sink. If not, heat sink will need to be determined by feed flow.

Question 10

For the Heat Sink CSFST, what is the basis for checking total feedwater flow to S/G’s > 240k lbm/hr?

Answer 10

This is the minimum feed flow to restore level and maintain heat sink. Failure to meet this flow requirement at this point will create a RED path to FR-H.1.

Question 11

For the Heat Sink CSFST, what is the basis for checking # in all S/G’s < 1090#?

Answer 11

If S/G # > 1090# (> highest safety setpoint), then S/G design limit would be exceeded and integrity would be challenged.

Question 12

For the Heat Sink CSFST, what is the basis for checking NR level in a S/G’s < 67%?

Answer 12

Overfeeding (or SGTR) may cause level to go high, which may cause unwanted atmospheric releases OR challenge integrity. Remember, the PORV’s are meant to pass ONLY steam.

Question 13

For the Heat Sink CSFST, what is the basis for checking all S/G’s < 1070#?

Answer 13

If a S/G safety is open, then an un-isolable heat removal path exists. The preferred method would be through the dumps then the PORV’s.

Question 14

What are the FOP criteria for FR-H.1?

Answer 14

1. Cold Leg Recirc: If RWST level < 30%, go to ES-1.3.
2. SI Actuation following block of Auto SI: If either condition occurs prior to step 20, then manually actuate SI based on operator judgement:
   
   • Subcooling < 40F, -OR-
   • PZR level cannot be maintained > 16% (28% adverse)
3. Control Room Pressurization: If an SI signal is actuated, then maintain one pressurization fan running during subsequent recovery actions.
4. S/G Feed Restrictions following RCS Bleed and Feed.

Question 15

What condition would create a RED path for FR-H.1, but would NOT require the procedure to be performed?

Answer 15

If total feed flow is < 240k lbm/hr due to operator action. This is the first caution in the procedure.

Question 16

In FR-H.1, what are the methods for feeding S/G’s in order of preference?

Answer 16

• AFW
• AFW from other unit
• MFP
• Condensate (Hotwell pump/Condensate Booster Pump)

Question 17

In FR-H.1, what is the purpose for securing RCP’s prior to establishing feed from a MFP?

Answer 17

They are secured to remove heat addition into the RCS from the RCP which will extend the S/G inventory.

Question 18

What conditions would require transition to E-1 (Loss of Primary or Secondary Coolant) from FR-H.1?

Answer 18

• If NO bleed path through the PORV’s exists and subcooling requirements are NOT met. (There is a LOCA)
• If the operator has reached to point where PORV(s) are to be closed and a bleed path cannot be closed. (PORV and block valve are stuck open)

Question 19

While performing FR-H.1, why is steam flow to the MSR’s isolated and what valves are closed?

Answer 19

• This prevents losing S/G inventory through the MSR’s. The only steam load the operator wants is the MFP’s.
• The operator closes the isolation valves to the MSR’s.
  
  • Unit 1: MMO-401, 402. MRV-411, 412.
  • Unit 2: MMO-431, 432, MRV-411, 412.

Question 20

While performing FR-H.1, what trips must be defeated to start a MFP?

Answer 20

• Rx Trip to MFP’s
• SI to MFP’s
• S/G Hi-Hi trip to MFP’s

Question 21

While performing FR-H.1, what must S/G pressure be in order for the condensate (hotwell and condensate booster pump) to feed the S/G?

Answer 21

< 370#

Question 22

While performing FR-H.1, why must SI be actuated and reset prior to establishing feed flow from Condensate?

Answer 22

• One S/G will be depressurized to < 370# in order for condensate to feed the S/G.
• AUTO SI from steam line D/P needs to be defeated prior to depressurization.

Question 23

While performing FR-H.1, what actions must be taken if only one PZR PORV can be opened when establishing RCS Bleed and Feed?

Answer 23

Establish alternate bleed paths via high point vents.
- PZR vents: NSO-61 thru 64
- Rx Head Vents: NSO-21 thru 24

Question 24

How is ESW aligned to the AFW pump suctions?

Answer 24

WMO-753, 754, and 744 from the control room.

Question 25

While performing FR-H.1, when must RCS bleed and feed be initiated if no CCP’s are running? (Assume all S/G’s are > 31% WR level)

Answer 25

Immediately to ensure sufficient SI flow.

Question 26

Referring to FR-H.2 (Response to S/G Overpressure) what is meant by the “Affected” S/G?

Answer 26

Refers to any S/G in which pressure is > 1090#

Question 27

What conditions would require transition to FR-H.3 (Response to S/G High Level) from FR-H.2?

Answer 27

• Affected S/G Level > 91% (89% adverse)
• At this level the upper tap could be covered and could be causing the overpressure condition.

Question 28

While performing FR-H.2, what are the methods for depressurizing the affected S/G?

Answer 28

• S/G PORV’s
• Steam supply to the TDAFP
• Basis also says any other available means.

Question 29

When performing FR-H.3, why is SG NR level >91% (89% adverse) such a concern?

Answer 29

Above this NR level, the operator cannot be sure that S/G level has remained below the steamline.

Question 30

What are the negative effects of overfilling a S/G?

Answer 30

• Valve inoperability due to two-phase flow.
• Water hammer.
• Added weight on the main steam piping and piping supports.

Question 31

At what S/G NR level is water considered to be above the upper tap?

Answer 31

91% (89% adverse)

Question 32

While performing FR-H.3 how is water level lowered in the affected S/G when feed flow has been isolated AND entry to E-3 series procedures is NOT required?

Answer 32

S/G Blowdown