septic system concept - septic drain fields, also called leach fields or leach drains

septic system sewage tank water treatment waste leach fields drains drain wastewater sewerage sewer liquid pollution field piping effluent drainage pipe underground filter plumbing trench bacterium organic compound pipeline tube management contaminants trenches perforated pipes gravel disposal agricultural percolate pathogenic bacteria pathogens soil compounds digestive anaerobic pathogen concept illustration also called are subsurface facilities