Offizieller Kommentar
We can't actually see any measured areas in the public version of your link. You have to make the annotations public for us to see it. That being said, it certainly doesn't look there are any pits on that site that would require 46K cubic yards to fill.
Measuring random areas will give strange results. When you are drawing your polygon, imagine a stretched surface that goes between all those surface points. This is our dynamic base calculation. The volume that is present above this imaginary surface is counted as the volume. For the purposes of calculating the void volume, or volume of a pit, we use an imaginary plane at the highest selected polygon point and calculate the volume of air down to the ground surface. This is intended for drawing around the perimeter of a level surfaced pit.
