Environmental Science
articles by Will Kemp

Waste services in a small community

Wagait Shire council doesn’t provide a waste collection service – residents must take their own waste to the local dump (see earlier post). There are separate areas at the dump for different types of waste: a trench for putrescible and other general household waste, an area for green waste, some bins for recyclables, and an area for large, non-putrescible items like cars, furniture, building materials, etc.

The council has had bins for glass, plastic, and aluminium drink cans for about a year, because local residents wanted to be able to recycle. However, they have had no success in finding a way to dispose of the collected recyclables. Wagait Shire is 130km from Darwin and Darwin’s a very long way from anywhere where recyclable materials are processed, which means recycling is not really economically viable.

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Regional approaches to waste management

As outlined in the previous post, Wagait Shire is very small and has an extremely limited budget for waste disposal solutions. The council is effectively incapable of dealing with the community’s waste in an environmentally friendly manner.

The nearby Indigenous community of Belyuen (about 10km away) is a separate shire, with its own council and its own landfill site. Belyuen Shire’s population is even smaller than Wagait Shire’s, at around 250.

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Landfill gas and leachate control

Wagait Shire in the Northern Territory covers a small area, comprising a single community of approximately 350 residents on the north east coast of the Cox Peninsula, across the harbour from Darwin. As the population is so small, the shire council’s budget is severely restricted, limiting its options for managing waste disposal. The council provides no garbage collection and residents take their own garbage to the local dump, which is unsupervised apart from a low fence restricting dumping to the active part of the cell.

The community has no sewerage or reticulated water supply, but treated water is available from two large tanks which are operated by the NT Power and Water Authority and fed from bores situated a few kilometers away from the community and the dump.

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Mixed plastics recycling

There are three types of process that can be used for recycling mixed plastic waste: mechanical, chemical, and energy recovery (Al-Salem, et al., 2009).

Mechanical recycling generally involves cutting, shredding, or milling and some form of cleaning, before forming it into a new product (Al-Salem, et al., 2009). For most purposes, mechanical recycling requires single polymer plastics, but there are processes which can deal with mixed plastic – for example, forming it into construction materials.

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High temperature incineration of hazardous waste


The aim of this report is to explain the processes of high temperature incineration of hazardous waste, as well as its environmental risks and benefits and its advantages and disadvantages. Modern industrial processes generate a certain amount of hazardous waste that must be dealt with somehow. High temperature incineration aims to dispose of this waste as completely and safely as possible. However, even state of the art incinerators produce emissions and residues which are themselves hazardous. Modern incineration operations aim to minimize the environmental impacts of these emissions and residues and must abide by environmental legislation. Research completed in 2011 showed that continuous monitoring of dioxins in incinerator stack emissions is viable. Due to a lack of high temperature incineration facilities in Australia, considerable effort has been put into developing processes to recycle hazardous waste. The availability of incineration is a disincentive to such research and development, however it may reduce the risks of accidental pollution from stockpiles and the incidence of illegal dumping.

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