Pond Boss Forums POND CONSTRUCTION Soil questions moisture content for compaction

My primary question here is how to get the clay to the right moisture content/consistency to successfully compact. There have got to be some tricks to increasing my odds of success. I don't have easy access to a sheep's foot and it's only about 2000sq ft needing to be done so I really need to make it happen with a 4wd tractor.

I have a few hundred lbs of sodium bentonite left in case I need to redo or add more to some areas and I have a way to pump water in to fill and test pretty quickly. The picture was prior to mixing it in.

The bigger equipment rental companies in Waco should have some appropriate vibratory soil compaction equipment.

A Cat CP-74 padfoot roller is 34,000 lbs and has an 84" drum. It rents for $814/day up in my neck of the woods (Kansas). You will also pay several hundred dollars each way for trucking, but it will quickly knock out that job.

The CP-34 is a much smaller machine, but is still $580/day (for comparison).

The padfoot compaction machines will mix in the bentonite (a little) while compacting.

If you have disked in the bentonite, then wheel compaction (and proper moisture) might be sufficient. Do you have a neighbor that has a tractor with a lot of ballast weights or weighted tires? You might hire him to make a few passes.

It is difficult to judge slopes in photos. However, the slope in the foreground looks like it might be gentle enough to compact while driving across the slope.

OTOH, the slope in the back of the photo looks too steep to safely compact while driving perpendicular to the dip of the slope. BASED ONLY ON A VIEW OF THE PHOTO, you might need to drain the pond and compact that slope by driving up the dip from the bottom of the pond, and then backing straight back down.

What method did you use to incorporate the sodium bentonite?

I have a 3pt tiller so I tilled up the first couple of inches of soil, spread the bentonite, then dragged the soil back towards the top of the banks by floating my front end loader because the forward spinning tiller had pushed a lot of it down towards the water. I used a laser level to mark a line for the water level so I wasn't wasting much. It looked really good afterwards so I haven't messed with it since. I got on an off-road forum to see what I could put on my tires to keep the mud from sticking and I think I'm going to try either Pam or tire black, also found a post here saying just get the clay wet enough to where you can mold it with your hands. I did find a sheepsfoot for like $700 delivered and picked up, I know that is best but my wife is already giving me heck for spending so much time and money on this. I plan to take half a day to finish this tomorrow when a cold front hits and highs are 80 vs 100.. I'll try to upload a few pictures, if anyone else has any suggestions I'm curious. Thanks

Are you positive that 100% of the leaks are above the existing water line? For example, your pond could be tied to the ground water level. No amount of compaction and sealing above the water line will "fix" the problem if your pond is still connected to the ground-water table.

If you are sure you are correctly addressing the problem, then I think you should probably just "go for it" with the best available means of compaction at your disposal.

One of my most common "errors" on projects is to suffer from "the perfect is the enemy of the good" syndrome. I over-plan, rather than just performing the work, figuring out what went right (and wrong) and then better fixing the problem on a minor second step.

I usually determine that there was no way to get it perfect on the first try, especially for a new project that is NOT in my everyday job expertise.

That being said, yes you do need water on your soil to optimize your compaction - regardless of your method.

If your soil is still "fluffy" from the tiller, then I would water it lightly (like misting) to set your bentonite in place, rather than have it run down the slope. I would then keep watering to try and get your soil wet below the level where you have tilled. You will probably have to do that in small steps.

Without deep disking, or compacting in lifts, you are probably not going to get any significant compaction below the 3"-4"(?) that was well tilled. However, if you compact that layer very well AND your bentonite performs well, then that may be enough to fix your leaks.

Good luck on your project!