Final treatment and dispersal components provide the final removal of contaminants and distribute the effluent for dispersal back into the environment.  Several options are available for distributing wastewater in soil.  Gravity flow systems are the most widely used dispersal systems.  These systems will continue to be used in areas where the soil separation distances can be met, primarily because they are the least expensive alternative and require the least amount of operation and maintenance.

Pressurized distribution methods overcome a variety of site limitations.  Low pressure, subsurface drip, and spray distribution systems are designed to function in difficult areas.  These systems are pressurized, which assists in providing even distribution of wastewater.  These technologies also facilitate reuse of wastewater in the landscape.  These advantages, however, increase the operation and maintenance requirements.

Methods:

•      Soil Adsorption Field
•      Conventional Drainfield System
•      Gravel-less Pipe
•      Leaching Chamber
•      Mound System
•      Low-Pressure Drainfield (LPD)
•      Low-Pressure Pipe (LPP)
•      Shallow Narrow Drainfield
•      Spray Distribution
•      Drip Distribution
•      Evapotranspiration Bed (ET)
•      Media Filter as Drainfield Option
•      Bottomless Sand Filter
•      Bottomless Peat Filter