AP-3 (SGTL)

Question 1

AP-3

What are the Rx trip criteria for SGTL procedure?

Are there any differences between the separate criteria?

Answer 1

• If L_pzr cannot be maintained (w/2 CCP and ltdn isolated)
• If L_vct cannot be maintained (also line up RWST to VCT)
• L_pzr, SI plant and leave AP procedure
• L_vct, L/U RWST to VCT and continue with step 5 of AP (while performing E-0)

Question 2

AP-3

Upon completing AP-3 (SGTL) what are the three procedures you can transition to and preference among them?

Include a negative impact for each choice

Answer 2

• Priority 1 - AP-3.1 (c/d using backfill), causes dilution of RCS
• Priority 2 - AP-3.2 (c/d using blowdown), craps up secondary plant
• Priority 3 - AP-3.3 (c/d using steam dumps), potential release to public

Question 3

AP-3/ OP O-4

What are the different action levels for various SGTL rates?

What are the different actions to take for each “Action Level”?

Answer 3

• 5-30 gpd ( Increased monitoring )
  
  • smpl more, brief AP-3
• 30-75 gpd ( Action lvl 1 )
  
  • smple more, brief AP-3
  • ODM
• 75-100 gpd ( Action lvl 2 )( LR > 1 hr )
  
  • smple more
  • MODE 3 w/in 24 hrs
    
    • once start s/d comply Actn lvl 3
• >100 gpd ( Action lvl 3 )
  
  • smple more
  • reduce pwr < 50% in 1 hr
  • MODE 3 next 2 hrs

Question 4

AP-3

When performing an RCS c/d and depressurization to stop the breakflow for SGTL, what factors will limit the cooldown?

Answer 4

• T.S. (do not exceed 100 deg in one hr)
• VCT L/U
  • manual m/u (60 deg/ hr)
  • auto m/u (40 deg/ hr)

Question 5

AP-3

When isolating the affected S/G for SGTL, what do you do if affected MSIV will not shut?

When commencing RCS depressurization to stop break flow, what are you limited by (when stop)?

Answer 5

• close remaining MSIVs
• isolate downstream isolation valves to minimize contamination of secondary system
• use 10%’s for unaffected S/G’s for subsequent c/d
• RCS subcoolng 20-30 deg