Appendix O - Quality of Effluent Suitable for Application to Surface Irrigation Appendix O Quality of Effluent Suitable for Application to Surface Irrigation Scope This appendix sets out methodology for determining whether the effluents discharged from small septic tanks or aeration systems are suitable for application to surface irrigation systems. Procedure The procedure shall be as follows: • The system shall be commissioned in accordance with the manufacturer's instructions and operated under stable conditions for not less than two months with an average daily load per bedroom of: - Volume, 300 L; - Five-day biochemical oxygen demand (BOD), 120 g;5 - Suspended solids, 120 g; - Total nitrogen, 30 g; and - Total phosphorous, 5 g. • The effluent samples shall be taken from the outlet ofthe disinfection chamber, or other location approved by the Council. • The effluent storage chamber shallbe emptied and allowed to refill before taking the first sample each day. • Testing shall be undertaken on four consecutive days. • Five samples shall be taken at 30 minute intervals during the test period when the plant is under a maximum flow of 120 L/bedroom for any 2 hour period. • At the completion of this 2 hour period on each day, the flow shall be increased to the maximum flow for a 30 minute period of 300 L and the effluent from the disinfection chamber shall be tested for free residual chlorine. At the completion of testing on each day, the flow shall be adjusted so that the flow to the plant during each 24 hour period is 300 L/bedroom. • Samples shall be taken in the presence of a representative of the Council or the approved testing agency accredited by the JointAccreditation System of Australia and New Zealand (JAS - ANZ). • The samples shall be tested by a registered laboratory for the parameters set out in Quality of Effluent below: App O - 1