Stump Job, Tree cut down in 2006

Lady wants a underwater scene cut into a tree stump. The tree was cut in 2006 and has been underwater once in a flood in 2008, under for about a week. The lady did not know what kind of tree it was.

My questions, A tree from 2006 to old to safely and easily carve?
A tree that was underwater for a week, would that fill full of sand?

I know it is not much information, but I don't have the experience and thought maybe you all had some input.

Thanks
Travis