I should be an expert on this, but i'm not.
Pigs pack ponds, but you gotta keep em in and you could end up like me and not
be able to kill one when the job was done. But you must make sure that
there is no debris (rock, roots, trees etc.) in the core or sides. Pack it
with clay and i just found out about a product that is not that expensive called
Benseal (bentonite) that goes in at 2' layers. If its a small pond use a
rubber liner (expensive but it works). Good Luck.
ts