Ok, need help here, I have a new raised garden bed I just finished building, a real beauty... and a necessity in this hard clay soil earth of Arizona... problem is this, I now need to order soil to fill the garden beds, and I need to know how much to have delivered. (sad I need to buy dirt sigh) Is there a formula, problem is they want to know how many tons of soil I need, my bed is 16"deep, 80' long and 3' wide, any help would be appreciated! Thanks

Judy