ABSORBS™ Naturally Aerobic Bottomless Sand Filters

ABSORBSABSORBS filters are advanced natural treatment and dispersal system designed specifically for difficult sites in category 1-3 soils. The system requires site-specific engineering and design. They occupy the smallest footprint of any system and can achieve higher treatment quality than the AWTS. Indeed, sandfilters are reported in AS/NZS 1547:2000 (4.2C5.1) as capable of treatment to 10mg/BOD5 and 10mg/SS against the recognised performance of proprietary AWTS’s of 20mg/BOD5 and 30mg SS.

The ABSORB aerobic bottomless sandfilter discharge control bed operates on a natural aeration dynamic from mass exchange of atmospheric oxygen into the soil/filter. The entire system is effectively passive once discharged through the pump. If there is no waste produced the system does operate but remains ready for service at any time of the year and are therefore suitable for holiday homes. No chemicals are used in the system as both the secondary treatment and dispersal train are completely sub-surface. There is no need for an external service contract however the system must be operated in accordance with the existing approval conditions for the septic tank system and the provisions set out in the Standard for the Construction, Installation and Operation of Septic Tank Systems in South Australia, Supplement A, Aerobic Sand Filters.

Another significant benefit is that turf can be planted over the filter and therefore can serve to represent part of the required open space provision. Moreover there are no root intrusion chemicals required and therefore RPZ (reduced pressure zone) valve required on the SA Water meter to prevent cross connection into potable water supply. (Note RPZ valves are required on any sub-surface drip system within a property connected to SA Water main supply)