I guess it will need emptying in a few years. Its supposed to be the
sort of 80 quid a year call out and pump thing, but I suspect I may
simply get in with a spade and wheelbarrow and dig out most of it and
stick it on the compost heap one day...

is there any reason why this shouldnt be done?


You have obviously never opened a septic tank! The liquid needs to be
removed as well as the solids. The method suggetsed is a non starter.

Peter Crosland