In conclusion, let’s examine a case-study that will put together all information given previously in this module.
Every year, millions of Muslims gather in the Kingdom of Saudi Arabia (KSA) for worship. The Makkah city landfills receive about 2.4 thousand tons of municipal solid waste (MSW) every day. But these quantities become 3.1 and 4.6 thousand tons per day during the Ramadan and Hajj respectively. A huge increase.
In 2016, all the collected MSW was disposed to landfill sites untreated, which resulted in greenhouse gas (GHG) emissions as well as water and soil contamination. The government decided to consider reuse and recycling as optimum techniques for waste management following source reduction.
Finally, the project has been implemented, and projected results are very good. It is estimated that only by recycling glass, metals, aluminium and cardboard, climate will be saved from 5.6 thousand tons emission of methane (CH4) per year (a major source of GHG emissions), and from many more thousand tons of CO2 of global warming potential (GWP). A very important positive impact on environment and sustainability will be obtained. But there will be an important economic result too: about 15 million Euros per year! Similarly, by recycling other above-mentioned recyclables, a net revenue of about 25 million Euros will be added to the national economy every year only from Makkah city. Moreover, technically, the waste recycling does not require high-skill labour or complex technology and thus can be easily carried out in any urban areas like Makkah city. So, this case teach us that with a good waste management we can both save the environment, improve sustainability, implement circular economy, and gain “green” money.
The key message
Through this module, you have understood at first what is waste and how it should be prevented, collected and treated according to a circular economy approach and the modern idea of sustainability. Then, you have learned to identify eight main types of pollution: atmospheric pollution, soil pollution, water pollution, thermal pollution, light pollution, electromagnetic pollution, radioactive pollution and noise pollution. Finally, you have discovered the relationships among circularity, sustainability and an appropriate management of waste. The crucial point is changing our way of thinking. So, we suggest you to reflect over this quote from Albert Einstein: «The world we have created today, as a result of our thinking, has problems that cannot be solved by thinking in the same way we thought when we created them…»