Traer's wastewater treatment uses an aerated lagoon, a simple wastewater treatment system consisting of holding cells, or ponds, and artificial aeration which introduces large quantities of oxygen into the wastewater. Oxygen is used by the bacteria that are present in the wastewater stream to breakdown and remove, or digest the solids in the wastewater. Adequate aeration is also an important element in keeping the lagoons content mixed and in suspension. With adequate mixing, incoming pollutants and wastewater are better distributed throughout the entire lagoon volume. This results in more uniform and efficient treatment. Generally an area is provided at the end of the treatment process where aeration is not present. This is called the quiescent zone. In this zone any remaining solids are allowed to settle out before the water leaves the treatment plant.