Why is proper filling necessary when abandoning a septic system?

Proper filling is crucial when abandoning a septic system primarily to ensure public safety and environmental protection. When a septic system is no longer in use, it's essential to fill the system adequately to prevent any potential hazards associated with its abandonment. An improperly filled septic system can lead to the release of harmful pathogens and contaminants into the soil and groundwater, posing health risks to nearby residents and wildlife. This filling process can also prevent surface instability or sinkholes, which could occur if voids are left unfilled. Therefore, adhering to these practices safeguards public health and maintains environmental integrity, making it a vital step in the process of abandoning a septic system.