DEFINITION OF WASTE
Waste, or rubbish, trash, junk, garbage, depending on the type of material or the regional terminology, is an unwanted or undesired material or substance. It may consist of the unwanted materials left over from a manufacturing process (industrial, commercial, mining or agricultural operations,) or from community and household activities. The material may be discarded or accumulated, stored, or treated (physically, chemically, or biologically), prior to being discarded or recycled. It is also used to describe something we use inefficiently or inappropriately.
THE PROBLEM
Waste can be regarded as a human concept as there appears to be no such thing as waste in nature. The waste products created by a natural process or organism quickly become the raw products used by other processes and organisms. Recycling is predominant, therefore production and decomposition are well balanced and nutrient cycles continuously support the next cycles of production. This is the so-called circle of life and is a strategy clearly related to ensuring stability and sustainability in natural systems. On the other hand there are man-made systems which emphasize the economic value of materials and energy, and where production and consumption are the dominant economic activities. Such systems tend to be highly destructive of the environment as they require massive consumption of natural capital and energy, return the end product (waste) to the environment in a form that damages the environment and require more natural capital be consumed in order to feed the system. Where resources and space are finite (the Earth isn’t getting any bigger) this is ultimately not sustainable.Â
The presence of waste is an indication of overconsumption and that materials are not being used efficiently. This is carelessly reducing the Earths capacity to supply new raw materials in the future. The capacity of the natural environment to absorb and process these materials is also under stress. Valuable resources in the form of matter and energy are lost during waste disposal, requiring that a greater burden be placed on ecosystems to provide these. The main problem is the sheer volume of waste being produced and how we deal with it.
HOW IS WASTE DEALT WITH?
Most contemporary waste management efforts are focused at local government level and based on high tech / high energy waste disposal by methods such as landfill and incineration. However these methods are becoming increasingly expensive and energy inefficient. The financial costs of managing the long-term environmental impacts of waste disposal are many times what is actually charged for this service and in many cases corrective action is not remotely feasible. The purely environmental costs such as negative effects on habitat, wildlife and biodiversity are also recognised. In other words waste disposal is not sustainable and will have negative implications for future generations.
Landfill
IS ORGANIC WASTE A PROBLEM?
Between 21% and 40% (by weight) of municipal solid waste in South African cities is organic, increasing to up to 45% if you include paper and cardboard. If the soil component of this waste is included, more than half the waste sent to landfill can be used as a growing media for plants. Considering the investment that went into creating the organic waste (and the nutrients and energy contained in it) this is too valuable a resource to simply throw away. However, organic waste sent to a landfill rots under anaerobic (without oxygen) conditions, giving off methane gas. Methane is one of the 'greenhouse gases' that trap heat in the atmosphere, contributing to climate change. Methane is particularly bad in that weight for weight it traps 21 times more heat than carbon dioxide.Â
While garden waste can be shredded or chipped for use as mulch and compost, food waste is putrescible (it becomes putrid, smelly) and attracts pests like rats and flies if it is left to rot. In order to prevent potential health and environmental problems, food waste is generally taken to landfills and buried or to fed to pigs. Feeding kitchen waste to pigs is not an ideal solution to food waste as this practice can promote the spread of swine fever, parasites and pathogens.
WHAT CAN WE DO?
Clearly, more appropriate and sustainable approaches to waste need to be adopted. To be sustainable we need to move the emphasis toward a system that is local, community based, makes use of low tech / low energy systems and is focused on waste minimisation. This is an approach which we at FullCycle advocate.
Other methods of managing waste include:
Waste minimization is an approach that aims to reduce the production of waste through education and the adoption of improved production processes and less wasteful practices.
Recycling, by separating certain materials within the waste stream and reprocessing them. The recycling of many materials is currently not financial