I think the sawdust yard might just cover a 4x8 sheet of pywood, with a double row of lumber stacks along the road in.
Oh, I just remembered they had an icehouse (or the remains of one) down at the river end. Probably what they were keeping the sawdust for. Ice was cut from the river in winter and stored for use in summer. I think they used sawdust to insulate it.
(This was in the fifties. There was still ice delivery in town. House across the street had an ice-box, not a refrigerator. Ice cart was horse drawn. We lived in an apartment building and we had a refrigerator, hooked up to a mechanism in the basement!)