AOP-39 Internal Plant Flooding Flashcards
What is Internal Plant Flooding?
Internal flooding is defined as uncontrolled leakage from breaches of water systems located inside Plant buildings that are connected to large water sources (eg, Service Water, Component Cooling Water, Fire Protection Systems, etc) which overwhelms removal capability and has the potential to submerge Plant equipment and/or areas identified in this procedure.
What are the entry conditions of AOP-39, Internal Plant Flooding?
Receipt of any of the following alarms with verification of flooding
- EK-28, “(EC-47) FIRE SYSTEM FLOW SCHEME ALARMS”
- EK-0171, “CONDENSATE PUMP ROOM FLOODING” (572’ elevation)
- EK-1352, “EAST SFGRDS ROOM SUMP HI/PANEL UV” (14.2% on LI-1108)
- EK-1353, “WEST SFGRDS ROOM SUMP HI/PANEL UV” (14.2% on LI-1107)
- EK-1354, “TURBINE FLR SUMP HI LEVEL” (50” above bottom of sump)
Flooding observed in any of the following areas:
- East Engineered Safeguards Room
- West Engineered Safeguards Room
- Auxiliary Feedwater Pump Room
- Condensate Pump Room
- Component Cooling Water Pump Room
- Auxiliary Building
- Bus 1C Switchgear Room
- Bus 1D Switchgear, Electrical Equipment, North Cable Penetration Room
- Cable Spreading Room
- EDG 1-1 Room
- EDG 1-2 Room
- Screen House
- Turbine Building
What are the automatic actions of AOP-39, Internal Plant Flooding?
- P-72A, P-72B, East ESG Room Sump Pumps start (first pump starts at 14.2 %,
- second pump starts at 15%, pump auto start blocked if CHR present)
- P-73A, P-73B, West ESG Room Sump Pumps start (first pump starts at 14.2 %, second pump starts at 15%, pump auto start blocked if CHR present)
- P-45A, P-45B, Turbine Building Sump Pumps start (first pump starts at 32”, second pump starts at 44”)
What are the reactor trip criterial of AOP-39, Internal Plant Flooding?
- Water depth approaches either operating Condensate Pump thrust bearings (height of security switch on AFW Pump Rm door)
- Water depth exceeds 5 inches in Bus 1C area
- Erratic equipment operation during Bus 1C area flooding
- Water depth exceeds 5 inches in Bus 1D area
- Erratic equipment operation during Bus 1D area flooding
- Erratic equipment operation during Cable Spreading area flooding
- Water depth greater than or equal to 9 inches in area of Buses 1A, 1B, 1E
What is the equipment trip criterial of AOP-39, Internal Plant Flooding?
Condensate Pump
- Water level at Condensate Pump thrust bearing (height of security switch on AFW Pump Rm door)
Electrical Buses 1A, 1B, 1E
- Water depth greater than or equal to 9 inches in area of Buses 1A, 1B, 1E
What is the mitigation strategy of AOP-39, Internal Plant Flooding?
- Determine the affected area and refer to applicable attachment.
- Open doors to release accumulated water and prevent/minimize component failures.
- Identify and isolate the flooding source.
- Considerations during flooding:
- In the event a fire is in progress, doors should only be opened and fire headers isolated with concurrence of the Fire Brigade Leader
- Due to multiple floor drains from different areas being routed to the Turbine Building Sump, it is necessary to immediately dispatch personnel to positively identify the affected area of excess water
- Unpredictable component failures may occur when flooded (eg, breakers may fail as-is, or open or close spuriously)
- Opening breakers prior to associated equipment becoming flooded precludes challenging supply buses
- Removing breakers from service (control power fuse removal) prior to their being flooded precludes spurious operation and operation in response to automatic signals
- Electrical safety procedure requirements (FP-EN-IS-123) must be met when performing breaker operations
- Hazards may exist due to flooded electrical components.
- Maintain plant in Mode 3, or stable condition unless cooldown directed by Shift Manager.
At what Engineered Safeguards Room sump level do you breach the floor?
27.1% is the floor level of 570 feet.
Use 5% per foot after that.
