Effluent Disposal Report

6.      RECOMMENDATIONS

            The Design Irrigation Rate of 20mm/week be adopted.
            The site be provided with an “Aerated wastewater-treatment system” capable of
             producing secondary effluent (with a thermotolerant coliform level equal to or less
             than 10), or an equivalent system (e.g Eco-Safe Sand Filter), to council’s approval in
             lieu of a septic tank.
            The disposal system be by, # A Fixed Surface Spray Irrigation System, as per AS/NZS
             1547:2000. Purple line is to be used from the ASTP to the irrigation area.
            An in-line Filter is to be installed between the Treatment Plant and the Irrigation System.
             Regular maintenance of the Filter shall be undertaken, according to the manufacturer’s
             requirements.
            The area shall be surrounded by a 150mm high earth mound or similar.
            The spray irrigation system shall distribute the effluent evenly (via a K-Rain Valve)
             within the designated area through coarse spray heads suitable for use with effluent, and
             shall not produce aerosols. All ‘plumes’ shall be evenly distributed and fixed in place
             with a height of approx. 0.3m and have a throw of no greater than 2.0m. It is estimated
             that approximately 28 plumes would be required.
            Non-return valves and flush-out valves should be installed on irrigation lines.
            The disposal area should be mulched to a depth of 100mm.
            Evergreen plants (approx. 30 plants) shall be planted to maximize evapo-transpiration.
            The disposal area required is 242m2.
             A daily flow rate of 690 litres/day (6 persons @ 115 litres per person/per day) has been
             adopted with a Design Irrigation Rate of 20mm/week, using Standard Water-reduction
             fixtures (Standard water-reduction fixtures include a dual flush 6/3 litre (minimum)
             water closet, shower-flow restrictors, aerator faucets, and a water-conserving washing
             machine). These fixtures must be installed. This flow rate will accommodate the
             proposed 4 bedroom residence using standard water-reduction fixtures only. A 100%
             reserve area (as per site plan) is to be kept free of buildings and traffic.
            The disposal area should be located in the vicinity of PT 1, PT 2 and PT 3 as per attached
             site plan.
            All set-back distances as required by the local authority shall be met;
             At least two signs stating “Recycled water- Do not drink” are to be erected on boundaries

        . Stormwater run-off including roofwater from buildings shall be diverted around and away
            from the disposal area. Imported fill may be required should there be insufficient soil available
            for the design of the disposal system.
            Please note: Personal Hygiene Products, Bleaches and detergents high in phosphorous will
            damage the capabilities of the Treatment System’s performance. Information should be
            sought by the Treatment System’s manufacturer for a guide of suitable products acceptable
            for the system.(some examples attached to this report).
Certification
The local authority may request that an inspection and certification is undertaken on the installation of the
system when nearing completion. The installer must contact Noosa Council prior to ‘burying’ the system,
if certification is required.

Yours Sincerely,




Michael S. Pinkney (Laboratory Manager) Report 19/0161 EDR-page3