<human>: What are the most common types of septic systems?
<bot>: The three most common types of septic systems are drainfield, leach field, and mound systems. Drainfield systems use a series of perforated pipes to remove waste from the home’s plumbing system and deposit it into a septic tank. Leach field systems use a similar setup but instead of a septic tank, they use a series of trenches filled with gravel or stone to filter out solids and allow liquids to pass through. Mound systems involve burying a large underground tank that is designed to hold the wastewater until it can be properly treated by the soil.