Clay - compost project

Of all solid municipal domestic waste produced in Australia approximately 50-55% consists of food and garden waste. Other components are paper (20%), plastics (6%), glass (10%), metal (5-7%) and other inorganics (10-15%). The organic fraction is by far the most environmentally polluting and can be hazardous. The reasons for this are 1) the enormous volume occupying 75% of landfill space, 2) its putrescible nature, causing it to be a source of pathogenic organisms, 3) the large volume of polluting gases released during the uncontrolled decomposition such as ammonia and methane, and 4) the decomposing organic matter is a major contributor to groundwater pollution through dissolution and its function as a carrier for inorganic pollutants (e.g. heavy metals). Furthermore it creates odour, attracts seagulls and is a breeding ground for rodents and insects. The major challenge in any integrated waste management strategy is to solve the problem of how to deal with organic waste. The current practice of land filling organic waste whether it includes compaction or other more advanced land filling techniques is becoming an inappropriate waste treatment practice and unsustainable in the long term. Because of the previously mentioned reasons and also the fact that it consumes large amounts of land, it results in low land value and generally strongly objected by residents, land filling is fast disappearing in major cities as a single waste treatment strategy. In low-density cities transport costs become prohibitive as suitable landfill space is only available well away from waste generation centres