What is the KSD? Plant tour Rates News & announcements Agenda Specifications Year end report & audit Home Town of Kennebunk		Final treatment After leaving the RBCs, the wastewater enters another pair of 140,000-gallon clarifying tanks called the final clarifiers. These allow any remaining biosolids to settle out of the wastewater. As with the primary clarifiers, these solids are pumped out and stored for later treatment. At the same time, the wastewater is treated with chlorine to kill any microorganisms. As the wastewater leaves the secondary clarifier, the chlorine is removed before the final effluent is discharged into the Mousam River.