The pumping frequency for septic tanks receiving greywater should be less than for those receiving combined wastes. Ashes must be removed from incinerating toilet units approximately every week. Emission control devices must be maintained. Paper bowl liners must be replaced before or after every use. A thorough site evaluation must be conducted in order to determine the appropriate level of pretreatment prior to final onsite subsurface disposal of the greywater portion of the wastestream.
Septic tanks can provide for only primary levels of treatment.
Odors may be emitted from incinerating toilet units. The ash product from these units must be properly disposed. Energy Consumption Septic tanks do not require power consumption. Wastewater drains by gravity from the house to the tank. Aesthetic Considerations Septic tanks are buried below grade, and usually do not have significant visual impacts on the site.