First of all, you should ask the local authority for planning permission for a solution that is compatible with your property.
As a rule, there are three solutions to choose from,… either a closed holding tank, a septic tank or a bio-treatment tank or self-cleaning tank.
In general, a holding tank can be installed anywhere, as a closed tank does not pose a risk to groundwater, but some self-blasting and septic tanks are not allowed in areas with poorly protected groundwater or areas with unprotected groundwater.