8.7 Green Wastes
Green waste includes grass clippings, tree, bush and shrub trimmings, branches and
other similar material resulting from domestic or commercial gardening, landscaping
or maintenance activities. In practice, the green waste data referred to in this report
relates to separated material delivered directly to local government facilities and
organic processors and does not include garden waste mixed with other materials in
household waste bins. Green waste is sourced from both domestic and commercial
sources of waste. Queensland’s local governments played an important role in the
collection and management of green waste, handling 91% of the total reported in
2016–2017 – of which over 500,000 tonnes was domestic waste self-hauled by
residents to local council facilities (Queensland Government 2018b). In 2016–2017,
a small number of Queensland’s local governments provided kerbside bin collection
services for recovering green waste (green bin lid) totalling 191,000 households
(representing 10.3% of Queensland households) (Queensland Government 2018b).
There are potential benefits to aerobically (and anaerobically) processing organic
wastes to produce quality soil amendment products, including, but not limited to:
• Aligning with industrial ecology principles and the ‘plate to paddock’ philosophy
• Utilising a wide range of waste/secondary-resource streams to make particular
products for a range of applications based on agricultural, nutrient or market
assessments
• Recycling of nutrients, in particular, carbon, nitrogen, phosphorous, potassium
and trace elements
• Replacement of synthetic fertilisers, which are often manufactured from
non-renewable sources and the global cost of which has significantly risen over
recent years
• Improvements to soil and plant health, including improvements to physical
properties such as increasing humus levels and soil moisture control
• Addition of value to the Queensland economy through the manufacture of valueadded products
There are also a range of benefits for local councils and, more broadly, for
diverting organic waste from landfill including:
• Extending the useful lives of the existing landfill and in doing so deferring
significant capital expenditure required for a replacement landfill
• Reducing greenhouse gas (GHG) emissions caused by the anaerobic breakdown
of organic waste in landfills, which may include considerations for minimising
any future carbon liability should a direct carbon tax for the sector be reintroduced
• Avoidance of the landfill levy
The quality of any final compost, mulch, soil conditioner product, etc., is heavily
influenced by the input feedstock as well as the compost processing process (including pretreatment and post-treatment technologies). These considerations also influence costs in terms of opportunities for gate fees, costs of treatment per tonne and
8 Sustaining Queensland’s Agricultural Sector: Challenges and. . .
127
Green waste includes grass clippings, tree, bush and shrub trimmings, branches and
other similar material resulting from domestic or commercial gardening, landscaping
or maintenance activities. In practice, the green waste data referred to in this report
relates to separated material delivered directly to local government facilities and
organic processors and does not include garden waste mixed with other materials in
household waste bins. Green waste is sourced from both domestic and commercial
sources of waste. Queensland’s local governments played an important role in the
collection and management of green waste, handling 91% of the total reported in
2016–2017 – of which over 500,000 tonnes was domestic waste self-hauled by
residents to local council facilities (Queensland Government 2018b). In 2016–2017,
a small number of Queensland’s local governments provided kerbside bin collection
services for recovering green waste (green bin lid) totalling 191,000 households
(representing 10.3% of Queensland households) (Queensland Government 2018b).
There are potential benefits to aerobically (and anaerobically) processing organic
wastes to produce quality soil amendment products, including, but not limited to:
• Aligning with industrial ecology principles and the ‘plate to paddock’ philosophy
• Utilising a wide range of waste/secondary-resource streams to make particular
products for a range of applications based on agricultural, nutrient or market
assessments
• Recycling of nutrients, in particular, carbon, nitrogen, phosphorous, potassium
and trace elements
• Replacement of synthetic fertilisers, which are often manufactured from
non-renewable sources and the global cost of which has significantly risen over
recent years
• Improvements to soil and plant health, including improvements to physical
properties such as increasing humus levels and soil moisture control
• Addition of value to the Queensland economy through the manufacture of valueadded products
There are also a range of benefits for local councils and, more broadly, for
diverting organic waste from landfill including:
• Extending the useful lives of the existing landfill and in doing so deferring
significant capital expenditure required for a replacement landfill
• Reducing greenhouse gas (GHG) emissions caused by the anaerobic breakdown
of organic waste in landfills, which may include considerations for minimising
any future carbon liability should a direct carbon tax for the sector be reintroduced
• Avoidance of the landfill levy
The quality of any final compost, mulch, soil conditioner product, etc., is heavily
influenced by the input feedstock as well as the compost processing process (including pretreatment and post-treatment technologies). These considerations also influence costs in terms of opportunities for gate fees, costs of treatment per tonne and
8 Sustaining Queensland’s Agricultural Sector: Challenges and. . .
127