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If you owned it, and had lots of time on your hands, it would work for getting the dirt out of the hole. But, I think it'd take a lot of time. You'd need other equipment to compact the pond basin, and something to help contour the bottom.

The mini excavators don't have a large bucket, so it'd take a while to fill even the 5 yd dump truck.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).