Dudley,
Max depth would be 7 feet. When you say "square of" do you mean square root of or squared?
40 feet X 80 feet X 7 feet = 22,400 cubic feet divided by 27 = 829 cubic yds. Of course it would be less than that due to the slope.
I was assuming 1:1 or 2:1 because the slope will be as steep as possible.
How do I proceed again?
