Circulating Water & Screen Wash (RQ-I-4721)

Question 1

U1 & U2 are 100% Power. Given the following:

• A terrorist organization sucessflly detonated explosives on all three intake structures rendering them incapable of supplying Circ water
• Both Units are being shut down
• Forebay level is lowering

What are the implications and options available with respect to ESW suction supply

A) If the forebay continues to lower, the ESW suction from the forebay may be re-established by opening WMO-30, Center Intake isolation valve.
B) In order to maintain a suction water source to the ESW pumps, the Emergency Forebay Valves (1-WMO-17 and 2-WMO-27) must be manually opened.
C) The Emergency Forebay Valves (1-WMO-17 and 2-WMO-27) will receive an AUTO open signal on low forebay level to maintain suction to the ESW Pumps.
D) Suction to the ESW pumps will be maintained as long as the Circ Water system discharge tunnel valves remain open.

Answer 1

B) In order to maintain a suction water source to the ESW pumps, the Emergency Forebay Valves (1-WMO-17 and 2-WMO-27) must be manually opened.