re: I wondered about that sort of thing... - I understand that they will deduct anything that was deposited by us.
They will do subjective diggings... studying the soil at different depths as they go along.
I know this was a prelimiary and low cost mission so they did what they had to, but in the future, it would be grand if a second generation MER fleet could do such diggings and even drill up some skinny core samples. Maybe they could attach a micro LEM somewhere so they could bring it back.
Ahh, sorry!