Due to the large collections of organic matter and availability of anaerobic conditions, accounting for roughly 18.2% of methane emissions globally in 2014. When waste is first added to a landfill, oxygen is abundant and thus undergoes aerobic decomposition; during which time very little methane is produced. However, generally within a year oxygen levels are depleted and anaerobic conditions dominate the landfill allowing to takeover the decomposition process. These methanogens emit methane into the atmosphere and even after the landfill is closed, the mass amount of decaying matter allows the methanogens to continue producing methane for years.
“South Africa is running low on landfill space. … “When organic waste is landfilled, it rots and produces methane. This methane is 22 times more damaging to the environment as a greenhouse gas than carbon dioxide”
“There are those proactive individuals who see the benefit of composting their food waste, but the sad reality is that most organic waste ends up in landfills”
A recent audit conducted by the Council for Scientific and Industrial Research (CSIR) showed that almost 40% of all waste that ends up in South African landfills is organic and biodegradable. This represents a significant loss of nutrients that could be used for compost and soil fertilization.
The CSIR research also estimates that food waste costs South Africa R10 billion every year. To cut this cost, on-site composting is one of the best solutions. Home kitchens, university dining halls, restaurants and business canteens can implement compost solutions to avoid sending organic waste to landfills.
Over 43 million cubic meters of Methane gas are released from South African landfills every year
One of the key advantages of on-site composting is that it produces a natural, valuable and useful product in the form of fertile compost for gardens. It also saves money. We measured that food waste composting activities reduced food costs by 4.2% and kitchen consumables by 11.8%
Although it is possible to build new landfills, it is a costly solution to the problem of decreasing landfill space. Constructing new landfills is expensive and these will no doubt be built further away from our expanding cities, which will further drive up the cost of waste disposal.
As the city moves to implement programmes to reduce the volume of waste going to municipal landfills, Johannesburg residents need to realize that the landfill airspace crisis is their problem and not something they should just push on to the municipality.