+1 FWIW when I first dug mine, we used a 3 inch and got by. We were still not able to load directly into trucks as the soil (sand, gravel and some clay mix) was still super staturated with water and it was like digging thick soup. We had to pile it on the side and let it drain. I did recently do an expansion without pumping down. As Esshup points out, you can't see what you're doing and the bucket is half water and half soil. The excavator had to be greased twice a day.


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