I do not have any personal experience with the product. But I have said in the past, and continue to do so, that these soil amendments are questionable at best and a waste of money at the worst. To get them to work, typically you need many more times the amount/area application then recommended by the product directions. Also, the primary area of the leak MIGHT NOT be the area manifested on the backside of your dam. Too bad on the money, but as I said, these products take a lot more and a lot more $$$ if they MIGHT work for you.  Not much else I can say.