Occasionally property owners complain about odors from their onsite sewage treatment system. There are several locations within an onsite system where odor can be an issue.Septic tanks, through the anaerobic treatment process, create gases — primarily hydrogen sulfide, ammonia, methane and carbon monoxide.Hydrogen sulfide is a colorless, flammable gas that smells like rotten eggs at low concentration levels in the air. Hydrogen sulfide is both an irritant and a chemical asphyxiant (it will take the place of oxygen so there is not enough for someone to breathe). Low concentrations may irritate the eyes, nose, throat and respiratory system. Asthmatics may
