I'm a bit worried about the clay at my site.

I read up on the ball & pencil test, as well as the bucket test.

I have yet to try them.

You can see my pond plan here:
http://www.flickr.com/photos/etd66ss/

I plan to buy a 10-15 ton Dozer this spring to build the pond in conjunction with my Ford 575D Backhoe.

You can see the layers of soil I found while digging my test hole.

The clay I hit seemed sandy-clay at first, and then silty-clay when it turned gray.

When dry, the clay crumbles very easily.

The gray clay was moist when I dug into it, but was had fine layers that sheared apart really easily.

I plan to go 20-25ft deep with this pond. I was assured by the county civil engineer I will have absolutely no problems with the pond holding water.

My lot used to be at the bottom of Lake Ontario 30,000 years ago...

I'm new to pond building, and new to soil analysis.

Any and all advice on my project is welcome.

Thanks!