Please check my calculations:
Volume = Area x Height
= (Pi x radius x radius) x height
= 3.14 x 330ft x 330ft x 220ft
= 75228120 cubic ft
Barrels of oil = (Volume / 5.61458) x 20% recoverable
= (75228120 / 5.61458) x 0.2
= 2.68 Million Barrels
I think that is only for 1 interval, right???