Access matters
Risers, lids, inlet/outlet components, and the tank itself must remain accessible. A structure can also create unsafe confined-space or structural conditions during service.
Check the approved plan
If an existing building already overlaps suspected septic components, locate the system and contact the local authority or qualified septic professional before disturbing the area.
What to verify locally
Permitting, inspection, setbacks, acceptable system types, professional licensing, and design requirements are controlled by state and local authorities. If your question affects construction, a property purchase, a repair, or drinking-water safety, confirm the answer with the local health/environmental department.
Primary reference
U.S. EPA — Frequent Questions on Septic Systems ↗
U.S. EPA — How to Care for Your Septic System ↗
Reviewed August 26, 2026.