Ok, I took a couple of pictures of it. I don't know what it is, but I
believe it is about as heavy duty as it gets for water retention. I
remember them saying something about there being laws for containing pig
waste that were really strict and this stuff is made to do the trick. You
can see the seam that has been melted between the two sheets. Once it had
been joined they could pull large sections of this stuff around without
worrying about any of it tearing.

http://www.geocities.com/fastfwd01/DSC00003.JPG

http://www.geocities.com/fastfwd01/DSC00004.JPG

This stuff was installed in a pretty big yard pond:


http://www.geocities.com/fastfwd01/DSC00006.JPG

http://www.geocities.com/fastfwd01/DSC00013.JPG

it's pretty ugly exposed too!

--
A sickened mind and spirit
The mirror tells me lies
Could I mistake myself for someone
Who lives behind my eyes
Will he escape my soul
Or will he live in me
Is he tryin' to get out or tryin' to enter me