esshup, If you had a small test pond, say 10x10 or 20x20, why not put a foot of water in the bottom so at least the powder can land in water or 'very wet sand' and float down to simulate what a 'on the water' application would be like. Then apply part B, then slowly add more water, as water level slowly comes up, reapply?
Does it have to be applied to dry sand and tilled under? You have the option to at least wet the sand or have temporary standing water and treat that right?
