EDG Fuel Oil System

Question 1

EDG Fuel oil system consists of:

Answer 1

• A single Diesel Fuel Oil Storage Tank (DFOST) 25000G
• Transfer Pumps (By DFOST)
• Four (two each) Fuel oil pumps (Manual pump and engine driven)
• Two EDG Day Tanks (EDG room) 275G
• Two AFOST (3rd level of Radwaste)

Question 2

Diesel Fuel Oil Storage Tank (DFOST)

Capacity
Minimum Level, lo level alarm

Answer 2

• Filled from Unit 1 Vertical Fuel Oil Storage Tank
• Capacity is 25,000 Gallons
• ITS Minimum Level is 19,000 gallons available to the EDG’s (ITS)
• DFOST Lo Level Alarm at 85% (= to 19039 gallons)

Question 3

EDG Fuel Oil Day Tanks:

Capacity
Minimum level and why

Answer 3

• Capacity: 275 gallons each

- ITS minimum level is 140 gallons, or 12’’ in tank (Based on operating its respective EDG for 35 minutes at 110% load)

Question 4

DFO (Diesel Fuel oil) Pumps powered by?

Answer 4

MCC-5 and 6

Question 5

ITS Fuel Oil Requirments

DFOST
DFOST and U1

Based off of?

Answer 5

• 19,000 gal available to the EDGs in the DFOST
• 34,000 gal total available from both the DFOST and Unit 1.
• Based on having sufficient quantity so that ONE EDG in the event of total loss of normal and auxiliary power, can operate for a period of SEVEN days while carrying maximum load required for a LOCA

Question 6

EDG auxiliary Fuel Oil System

AFOST

Answer 6

• Provides additional run-time for the EDGs upon a loss of the DFOST.
• Consist of 2 alternate fuel oil storage tanks (AFOST)
• Tanks are manually aligned for service and provide a minimum of 4gpm by gravity feed.
• Can only be used for a DBT, design basis treat, or BDB, any other use could constitute a violation.

Question 7

Transfer pumps

Answer 7

• Normally 1 for each EDG
• Can be cross connected to either day tank
• Controlled from lvl switches on Day tanks
• Activation of fire suppression trips pump