I am going to buck the trend and recommend a lagoon system for POME wastewater. This recommendation is based on the following assumptions:
- Sufficient land exists to install lagoons
- Lagoons can be constructed that only discharge water at the designed effluent point
- Periodic dredging can be done to deal with accumulated solids - inorganic and biological solids can buildup no matter how much mixing is provided
- Advanced systems require more attention, maintenance, and experienced operators. Lagoons once constructed are much more forgiving
- Prior to discharge, the water is aerated to prevent dissolved oxygen depression near the lagoon effluent