Another thing is that if you are trying to compact frozen ground, you cannot. SO, a pond cannot be properly compacted when ground temp or ambient air temp is much below freezing. It can be dug when it's that cold out, but not finished.

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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).