Well by my best Judgement the holding areas appears to be 7 Acres
So your dirt is approximately the same volume as 3 Capitol towers. , According to Wikipedia, acre is 43,560 square feet. So, if you dig 1 foot deep over an acre, you get 43,560 cubic feet of dirt.
So if we reverse that and go by what a tip truck would dump would be 8 foot high so lets just say 6 foot high so that 6 x 43560 cubic feet per acre = 261360 cubic feet then x7 for the acre
= 1829520 cubic feet of material ready to process
The 7 acre paddock was cleared and compacted then a skim of gravel over it with the intention of using it for the stockpile
We already know what the Processing plant looks like
Will make interesting pics