<human>: What is the difference between a septic and a leach field?
<bot>: A septic system is designed to treat wastewater from a building. It uses bacteria to break down organic matter in the wastewater, which produces methane gas that can be used as an energy source. A leach field is designed to treat wastewater from a landfill or industrial facility. It uses soil to absorb the waste, which then filters it into groundwater.