6/17/2015 9:06 AM
We also used Bentonite Clay to seal a pond. During a renovation before I came to this property they enlarged a fairway and made a pond (for residential irrigation) above the elevation of the fairway. It was lined with clay and the owners were told it would not leak. Wrong! It had a slow weep which caused an extensive water bed on the fairway.
I researched different solutions that were also cost effective. The pond is not large (150'x50') but the quotes for a PVC liner were close to $50K. I spoke with some members from the oil drilling business and they recommended Bentonite which they use extensively in the drilling process. Cost of this was about $2800.
We figured at that price it was worth a try.
[u">The Process (Learning)[/u">
Pond had approximately 2' of water in it when we were informed of delivery. Pumped it out completely on a Thursday, product delivered on Friday and started applying on Monday. Product came in 1000 lb totes.
We used sheets of plywood to act as ramps from rim of pond where we could drive skidsteer to desired application area. We then opened the bottom of the tote and the material flowed like water down the plywood to the slopes and bottom of the pond. Using rakes and shovels we applied approximately 4" on the bottom and sides. We then used a rototiller to lightly till it into the top couple inches of the clay. Initially we then tried a plate compactor but that jut got clogged with clay and bentonite. We then tried driving our tractor with turf tires down into the bottom to wheel pack and that worked great. We had 2 areas we could not get to by dumping the product over the edge, so on Tuesday I thought I would try taking the skidsteer with a 1000 lb tote into the empty pond and then dump. I was a little nervous I would sink out of sight considering just 4 days earlier there was 2' of water in the bottom but the skidsteer barely left tire marks in the area we had done the day before.
It has now been 2 years since the application and we have yet to see and weepage from the pond onto the fairway or anywhere else.
If using this product, hazmat suits, good respirators, ear plugs and eye goggles are a must. It comes in a powder form that has the viscosity of water and is quite dusty. It gets in every crack and crevice you can think of and its intention is to seal so you do not want to be inhaling or absorbing it.
Been a great product for us and very happy with results. Results may vary with different soils but with clay or a loamy structure it works great. Feel free to contact me for more info.