The land size of 200 Hectare = ruffly 500 acres. On average there are 1,300 tons per acre. 437.5 Grains = 1 ounce
So, 1,300 x 500 = 650,000 tons
253 Grains x 650,000 = 164,450,000 devided by 437.5 =
375,885.71 ounces IMO
The pits were dug by hand (cost savings). The report is stating they need to go deeper thats all, still a good stock to have.