Grinding/removing stump and putting in pond. Is this ok?

I had a stump from a large, mature Maple (that was severely diseased and in bad shape) that I cut down in June '04
http://davesgarden.com/journal/d/i/1925/ It's the stump closest to the house.

I was able to finally grind (what I could) of the stump around the beginning of June '05. I wasn't able to grind much as it was still *very* hard and the grinder wasn't the best in the world.

So if I can, I'm going to grind again this year and take it down as far as I possibly can, along with any large roots.

My question is, can I put on pond over this whole area or is that something that's not recommended? I thought I could, but now I'm starting to question if this is a wise choice.
Also, can I use some of the ground wood materials as a "liner" of sorts to receive that actual pond liner? Or no?

Thanks for any suggestions and knowledge you can offer.
Annie

When those wood chips and roots, and any remaining portion of the stump finally rot they will reduce in volume, form a depression, and you will have the liner sinking. Not a good idea. Invest in and install the underlayment sold for pond liners wherever you put the pond. This underlayment will protect the liner from any object trying to surface from below and poking at the liner. Make sure you have removed any stones and removed or trimmed all tree roots before placing the underlayment. If the tree root is over an inch in diameter and from a tree you want to keep you risk harming the tree. Putting in a pond is hard work, hate to see you have a problem down the road that can be avoided now.

Mary