if you mean a 30 foot diameter circle, then pi x 152 x 3 = 2119.5 cubic feet of dirt
There is none. Because there is a hole! If you are asking how much dirt can fill the hole, then your answer is 27 cubic feet.
A cubic foot of dirt is about 100 pounds. To fill a ton, 20 would be needed, but to fill a cubic yard, 27 would be needed. As such, a ton of dirt would only fill about .74 cubic yards.
1 foot by 36 sq feet = 36 cubic feet of dirt is needed
8ft*6ft*10in 96in*72in*10in 960sqin*72in 69120 cubic inches of dirt or 5760 cubic feet of dirt.
I think 17 or maybe 38
Fourteen Foot Shoal Light was created in 1929.
33.5 cubic feet.
As you did not specify a depth, I can not provide an answer.
2.37 cubic yards.
There is no dirt...it is a hole