Pond Boss Forums POND CONSTRUCTION Soil questions Packing clay bottom

I would treat the sand/gravel with quality, high expansion rate bentonite or polymer first then compact 4-6" lifts of high plasticity clay over those areas. One can even treat the sand areas with additive, clay, additive, clay, etc. Lasagna style. I sealed my gravel veins using polymer and compacted clay in this manner. Here to help anytime - tj@hudlandmgmt.com