Although I was aware that the pollution caused by landfill couldn't be doing the environment much good, I hadn't realised quite how much the methane from such dumps contribute to global warming.
According to Innocent Sibeko, managing director of waste management company, Exergy Enviro Group, and one of the African Climate Leaders trained by Al Gore's Climate Reality Project, landfill accounts for a shocking 13% of all global methane gas emissions – and worryingly, methane is second only to carbon dioxide in terms of contributing to global warming.
Sibeko dropped his little bombshell during a presentation on possible African solutions to climate change at a recent 'Green Drinks' event in Johannesburg. Hosted by the South African branch of the former US vice president and Nobel Peace Prize winner's green charity, it – rather appropriately - took place in the garden of social and environmental enterprise, Food & Trees for Africa.
But it seems the whole issue of rubbish is an important and apparently underestimated one. The most recent (2012) National Waste Information Baseline Report indicated that, while South Africa generated approximately 108 million tonnes of waste in 2011, a shocking 98 million tonnes went into landfill, with a mere 10% being recycled.
To make matters worse, the Greenhouse Gas Inventory for South Africa, which was published earlier this year, found that total greenhouse gas emissions from landfill had increased by 72% from 2000 to 2010.
As a result, municipalities up and down the country are now being tasked with trying to find solutions, not least because many of their 1,327 documented sites are starting to hit capacity.
Two of Johannesburg's five landfill facilities, for example, currently extract, combust and flare methane in order to burn it off and get rid of it.
But towards the end of this month, there are plans to install four 1MW generators at ZAR 10 million (£555,835) a pop at the city's Robinson Deep site near Turffontein in a bid to harness the gas and generate electricity. The scheme will be the biggest landfill gas-to-energy project in South Africa.
Once the generators become operational early next year, Ener-G Systems Joburg, a consortium that won the 20-year build-own-operate contract, is expected to sell 5MW of power to state-owned monopoly power provider, Eskom.
This new energy source will provide electricity for 4,000-5,000 homes and cut greenhouse gas emissions by about 149,000 tonnes per annum.
But when all five landfill sites come online in future, the amount of power produced should rise to 19MW, providing enough electricity to supply a significant 12,500 middle-income households.
This situation will no doubt prove a welcome respite for Eskom, which is struggling to keep the country's lights on, a situation that led to rolling power blackouts in Gauteng earlier this year.
In a bid to stop rubbish being dumped in landfill in the first place though, the government is also keen to kick-start the recycling collection schemes now so familiar to everyone in the UK.
To this end, the goal of the Department of Environmental Affairs' National Waste Management Strategy is to ensure that all large towns and metropolitan areas have recycling-friendly separation-at-source schemes in place by 2016.
In the case of South Africa's biggest metropolis, Joburg, the objective is to save 20,000 tonnes of rubbish from going into landfill each year by rolling out a pavement collection service by the end of 2015.
But 20,000 tonnes would appear to be a drop in the ocean compared with the 1.6 million or so tonnes that end up in City dumps. It is also a far cry from the country's pledge to divert three quarters of its recyclable materials from landfill by 2022, a promise made on signing up to the Polokwane Declaration in 2001.
While the whole municipal recycling situation is obviously still a work in progress, the City has nonetheless set up 10 "buy-back" centres to deal with what material is reclaimed.
The centres house 25 co-operatives, small, medium and micro enterprises (SMMEs), which together employ about 500 people, while a further 42 garden refuse sites, about half of which are also operated by SMMEs, accept recycled waste too.
And it is on this kind of model that Sibeko's Exergy Enviro Group operates. Based in the Vaal Triangle, an urban area about 60km south of Johannesburg, Exergy employs 27 "waste pickers" to reclaim recyclable material from landfill sites or people's rubbish bins in order to sell it on to bigger recycling companies.
Workers are provided with training to help them identify waste suitable for the market and are encouraged to form cooperatives in order to work more effectively together.
In fact, the South African Waste Pickers Association, which is in the process of being registered as a trade union, estimates that there are about 60,000 such informal workers employed across the country, each earning on average about ZAR 120 per day (£6.66).
And certainly they are a common sight around the suburbs of towns and cities in South Africa, emerging out of nowhere with their huge bags and shopping trolleys before the bin-men can arrive to see what they can find of value.
But there is growing concern among this community that, as municipalities increasingly hand out contracts to more formal waste management companies, they will be the ones to lose out – a situation that obviously threatens their livelihood and their ability to feed their families.
While former Minister of Energy Dikobe Ben Martins promised that waste pickers would be considered as part of all government waste-to-energy projects, apparently no reference has been made to them in the National Waste Management Strategy.
But there are already reports of worker numbers being cut at landfill sites – and that is even before pavement collection kicks in properly.
So it appears that the old Yorkshire adage of "where there's muck, there's brass" could definitely be under threat for these waste entrepreneurs who, when all is said and done, are simply trying to make a living in a country where unemployment levels remain desperate.