Site and Soil Evaluation · MCU18/0084

benefit from such watering which also assists in disposal of the effluent via evapo-transpiration. Points to consider
in the construction of the area include the following:


            To avoid runoff from the area it should be as level as possible. Any steep sloping areas should be
             terraced or retained and filled.
            Rainwater shall be diverted around the perimeter of the area by use of open catch drains or bunding.
             Similarly a retention bund should be constructed around the low side of the area to retain any effluent
             overflow.
            Sprinklers with a throw of not more than one meter shall be used and produce coarse droplets
             (instead of a fine mist) to minimise the risk of aerosol dispersion and wind drift of effluent. The plume
             height shall not be more than 300 mm above the finished surface of the irrigation area.
            The treated effluent must not be used for the irrigation of fruit or vegetables.
            Siting of surface irrigation shall be in a location away from regular pedestrian traffic and recreational
             areas, so there is no risk of direct spray or wind driven spray onto such areas.
            The area should not be within vehicle paths or be near children’s play areas.
            Treated effluent quality must conform to AS 1547-2000 and the Queensland Plumbing and Wastewater
             Code.

We have attached a site plan showing the proposed position of the Land Application Area and also some details
highlighting the construction techniques required for surface irrigation.

Preparation of irrigation area:

When a proposed irrigation area has a low permeability, it is particularly important to ensure that the permeability
of the soil in the irrigation area is improved and maintained and that there is an adequate cover of porous and
fertile topsoil to act as immediate storage of effluent applied to it, and to support rapid growth of vegetation on the
area to maximise evapo-transpiration.

Requirements of irrigation system:

All irrigation pipe work and fittings shall comply with all parts of AS 1477 or AS 2698.2. The distribution irrigation
lines should be buried to a minimum depth of 100mm. There shall be no cross connection between any irrigation
pipe work and the potable water supply. Any pipe work used for the transport of effluent included treated effluent
must be lilac in colour.

Along the boundary of the surface irrigation area there shall be at least two warning signs clearly visible to inform
the occupants of the premises that recycled water is used for irrigation. Each sign shall comply with AS 1319 and
have:

      (a)    lettering visible at 3m and
      (b)    wording:              Recycled Water
                                   Avoid Contact
                                   DO NOT DRINK

Prior to the use of the system, the warning signs and the landscaping and surface preparation must be completed.

Sighting of the Land Application Area:

The current Code of Practice for On-site Sewerage Facilities provides minimum horizontal/vertical separation
distances for Land Application Areas. They are as follows;

             Surface Land Application Areas (ADVANCED SECONDARY)
             Property Boundaries Upslope from the Area     -      2.0m
             Property Boundaries Downslope from the Area   -      4.0m
             Dwellings or buildings                        -     15.0m
             In ground swimming Pools                      -      6.0m
             In-ground potable Water Tanks                 -     15.0m
             Dams, Watercourses or Bores                   -     10.0m


   AUSTRALIAN SOIL INVESTIGATIONS                              5                                ASI Ref: 180061(A)