How much depth will come from the existing slope, and how much will have to be excavated deeper than that? The amount of dirt to be moved/removed makes a big difference in cost.

Other info dirt types will need:
Is there good clay in the basin area? If not, nearby? How far?
Any bedrock issues likely (porous limestone that will need sealed off/ bedrock needing removed)?

Last edited by Theo Gallus; 11/04/20 06:58 AM. Reason: wanted more intital conditions
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