England. Environment Agency Building Regulations (Part H-H2 Package Sewage Treatment Works) state that all wastewater (sewage) treatment plants should be sited 7m-10m from any inhabited part of the property. The building control officer for the site will make the final decision on exactly how far the plant should be sited. If the discharge is to a soakaway a sampling chamber must be provided before the soakaway. Soakaway drains must be constructed in the aerobic soil layer, i.e. within 700mm of ground level. Please visit the Planning Portal website for further information.