Containment De-inerting

Question 1

What is normal Containment Vent pathway and what sample results are required?

Answer 1

RB Vent system:
Iodine 131 <7.2 E-9 uCi/cc
Beta/Gamma <7.9E-9 uCi/cc

Question 2

What is pathway for Containment de-inert if higher than normal? what are limtis?

Answer 2

SBGT IF less than
I 131 < 3.5E-7 uCi/cc
Beta/Gamma <3.9E-6 uCi/cc

Question 3

What are required actions if drywell/torus conditions change while venting containment?

Answer 3

Terminate venting and resample to verify conditions prior to restarting

Question 4

Why should drywell pressure remain greater than or equal to torus pressure while venting?

Answer 4

To prevent cycling of torus to drywell vacuum breakers

Considered ESF actuation and potential 50.72 notification

Question 5

What are potential hazards in 2/3 EDG room when inerting containment?

Answer 5

Potential oxygen deficient enviorment due to nitrogen flowpath. Atmosphere sampled every 15 min to prevent

Question 6

During Post Accident conditions, where is containment vented to and what are limits?

Answer 6

Vented only to SBGT if less than:
I 131 < 6.3 E-5 uCi/cc
Beta/Gamma <2.1E-5 uCi/cc

Post accident containment samples valide for 7 hours for venting purposes

Question 7

When can CAM H2/O2 system be relied upon?

Answer 7

If heat trace/hot were on, then data valide after 15 minutes; otherwise wait 7 hours

Question 8

What is effect of starting/stopping DW coolers on PC temp and pressure

Answer 8

Can lead to violating containment Tech Spec limits for containment pressure and damage to MSIV pilot valves

When de-inerting, do not open vent valve unless DW/Torus pressure <0# to prevent uncontrolled release