GUIDELINES FOR ENVIRONMENTAL MANAGEMENT DRAFT EPA CODE OF PRACTICE – ONSITE WASTEWATER MANAGEMENT Publication 1364 December 2010 1 DRAFT EPA CODE OF PRACTICE — ONSITE WASTEWATER MANAGEMENT CONTENTS CHAPTER 1 — OVERVIEW OF THE ONSITE WASTEWATER FRAMEWORK ........................ 5 1.1 Purpose ...........................................................................................................................5 1.2 Stakeholders .................................................................................................................... 5 1.3 Wastewater definitions .....................................................................................................5 1.4 Scope ..............................................................................................................................6 1.4.1 Exclusions ....................................................................................................................................6 1.4.2 Sewered and unsewered areas ...................................................................................................6 1.5 Cumulative impacts ..........................................................................................................7 1.6 Legal framework ..............................................................................................................7 1.6.1 Environment Protection Act 1970.................................................................................................7 1.6.2 State environment protection policies ..........................................................................................8 1.6.3 Planning legislation and policies ..................................................................................................8 1.6.4 Australian Standards ....................................................................................................................9 1.7 Roles and responsibilities ................................................................................................9 1.7.1 EPA Victoria .............................................................................................................................. 10 1.7.2 Local government ...................................................................................................................... 10 1.7.3 Land capability assessors ......................................................................................................... 11 1.7.4 Building surveyors ..................................................................................................................... 12 1.7.5 Onsite wastewater system installers ......................................................................................... 12 1.7.6 Service agents ........................................................................................................................... 13 1.7.7 Property owners and occupiers ................................................................................................. 13 1.7.8 Water corporations .................................................................................................................... 14 1.8 Onsite wastewater treatment system approval processes .............................................. 14 1.8.1 Manufacturers’ certificate of approval process ......................................................................... 15 1.8.2 Property owners’ permit process ............................................................................................... 15 CHAPTER 2 — INTRODUCTION TO ONSITE WASTEWATER MANAGEMENT .................... 16 2.1 Sewage Management Options ............................................................................................ 16 2.1.1 Unsewered areas ...................................................................................................................... 16 2.1.2 Sewered areas .......................................................................................................................... 16 2.1.3 Onsite and cluster scale options ............................................................................................... 17 2.2 Effluent quality standards ............................................................................................... 18 2.2.1 Primary effluent standard .......................................................................................................... 18 2.2.2 Secondary effluent standard (20/30/10 and 20/30) ................................................................... 18 2.2.3 Advanced secondary effluent standard (10/10/10) ................................................................... 19 2.2.4 Secondary effluent standard with nutrient reduction ................................................................. 19 2.3 Principles of sustainable water resource management ................................................... 22 2.3.1 Waste hierarchy ........................................................................................................................ 22 2.3.2 Environmental sustainability ...................................................................................................... 22 2.3.3 Organic matter and nutrients ..................................................................................................... 22 2.3.4 Salts .......................................................................................................................................... 22 2.3.5 Small blocks .............................................................................................................................. 23 2.3.6 No offsite discharge of wastewater ........................................................................................... 24 2.4 Approved effluent dispersal and recycling systems ........................................................ 24 CHAPTER 3 — ONSITE WASTEWATER MANAGEMENT IN UNSEWERED AREAS ............ 26 2 DRAFT EPA CODE OF PRACTICE — ONSITE WASTEWATER MANAGEMENT 3.1 Onsite wastewater planning process .............................................................................. 26 3.2 Onsite treatment system options .................................................................................... 27 3.3 Wastewater generation .................................................................................................. 27 3.3.1 Minimum flow rates ................................................................................................................... 27 3.3.2 Increased flow rates .................................................................................................................. 27 3.3.3 High flow rates ........................................................................................................................... 28 3.3.4 Irregular and surge flows ........................................................................................................... 28 3.3.5 Intermittent flows ....................................................................................................................... 28 3.3.6 Reduced water flows ................................................................................................................. 29 3.3.7 Organic loads ............................................................................................................................ 29 3.4 Daily wastewater flow rates ............................................................................................ 29 3.4.1 Calculations for minimum daily domestic flow rates ................................................................. 29 3.5 Commercial premises .................................................................................................... 30 3.5.1 Organic loads from commercial premises ................................................................................. 30 3.5.2 Daily flow rates for community and commercial premises ........................................................ 31 3.6 Land capability assessment ........................................................................................... 33 3.6.1 LCA procedure .......................................................................................................................... 33 3.6.2 LCA independent review ........................................................................................................... 36 3.7 Onsite recycling and land dispersal options ................................................................... 36 3.7.1 Primary treated effluent land application systems .................................................................... 36 3.7.2 Secondary treated effluent land application systems ................................................................ 37 3.8 Advanced secondary treated greywater effluent (10/10/10) for indoor uses ................... 38 3.9 Setback distances .......................................................................................................... 39 3.10 Reserve areas ................................................................................................................ 41 3.11 System installation, use and maintenance ..................................................................... 41 3.12 Connection to sewer ...................................................................................................... 42 3.12.1 Split systems ............................................................................................................................