Which of the following can negatively impact the operation of a septic system?

Disposing of non-biodegradable items in a septic system can have a detrimental effect on its operation. When such items, which include plastics, certain types of wipes, and other materials not designed to break down naturally, are introduced into the septic tank, they can lead to blockages and prevent the system from functioning properly. These items can accumulate in the tank, obstructing the flow of wastewater and disrupting the biological processes crucial for breaking down organic matter. Furthermore, if these materials reach the drain field, they can clog the soil and impede the absorption of effluent, leading to backups or failures in the septic system.

In contrast, regular pumping and maintenance help ensure that the system functions efficiently by removing sludge and scum buildup. Adequate soil drainage is essential for the proper absorption of wastewater, supporting the septic system's operation. Proper sizing of the tank ensures that it can handle the volume of wastewater produced, which is crucial for maintaining the overall health and efficiency of the system. Therefore, the introduction of non-biodegradable items stands out as a key factor that can disrupt the effectiveness of a septic system.