What is the main function of the drainfield trenches in a septic system?

Study for the North Carolina Septic Inspector Exam. Use detailed flashcards and multiple choice questions with hints and explanations. Get exam-ready today!

The drainfield trenches are where the liquid effluent from the septic tank is distributed into the soil. Through perforated pipes in gravel-filled trenches, the liquid enters the surrounding soil and gradually infiltrates. The soil then provides filtration and microbial treatment, breaking down organic matter and reducing pollutants as the water disperses slowly, helping protect groundwater. Solids have already been separated in the tank, so the trench system’s job is not to filter solids or store treated wastewater, and monitoring groundwater is handled by separate measures rather than the trenches themselves.