if you read the conditions it first states a septic thank, at the end it states a propertrierty treatment unit if the percolation test for a septic tank fails. The type of unit wasn't specified in the planning, when i was talking to the engineer he said it was unusual to grant planning on the basis of doing a test later nor is there any service agreement in place, I been quaoted 3800 for the Bio cycle unit and 4000 for the raised percolation bed, i don't have a problem with spending the money if required but what i'm saying that if i redo the percolation test and it passes for a septic tank, should i not install one? The house next to me has planning since august