Answer the following questions
What do you mean by segregation of waste? How does it ensure safe waste disposal?
Segregation of waste means dividing the waste into different categories like dry and wet or biodegradable and non-biodegradable.
When waste is segregated, there occurs a reduction in the volume of waste that reaches the landfills. Air and water pollution is considerably reduced and it becomes easier to apply different processes of waste disposal like composting, recycling and incineration.
What is meant by open dumping of waste? Why is open dumping not considered as an environment friendly method?
In open dumping, waste materials are dumped in open low lands far away from the city.
This method is not environment friendly as the open pits spoil the sight of the area and become a breeding ground for mosquitoes, flies, insects, etc., that are the carriers of harmful diseases. They give out foul odour. The burning of waste material in the open dumps pollutes the air.
Another danger of open dumping is that rainwater could carry the harmful substances to the nearby streams, ponds or lakes and if the water seeps down it could pollute the groundwater.
(i) What is a sanitary landfill?
(ii) How is waste disposed of in a sanitary landfill?
(i) Sanitary landfill is a way of disposing refuse on land without creating nuisances or hazards to public health and safety. The waste disposal is carried out with minimal environmental damage and in areas already spoiled or in need of restoration.
(ii) In sanitary landfill, the waste undergoes the following five phases for safe disposal-
- In the first phase of operation, aerobic bacteria depletes the available oxygen and causes the temperature to rise.
- In the second phase, anaerobic conditions get established and lead to the evolution of hydrogen and carbon dioxide.
- Phase three establishes population of bacteria and the beginning of methanogenic activity, i.e., production of methane from the decomposition of organic matter.
- In the fourth phase, the methanogenic activity becomes stabilised.
- The fifth phase depletes the organic matter, and the system returns to aerobic state.
Give a reason for each of the following:
(i) Vehicles used for transporting waste should be covered.
(ii) Waste segregation is key to waste management.
(iii) Roads from plastic waste are environment friendly.
(i) Vehicles used for transporting waste should be covered as this prevents the wastes from being scattered. Waste should not be visible to public, nor exposed to open environment.
(ii) Waste segregation is key to waste management as when waste is segregated, there occurs a reduction in the volume of waste that reaches the landfills. Air and water pollution is considerable reduced and it becomes easier to apply different processes of waste disposal like composting, recycling and incineration.
(iii) Roads from plastic waste are environment friendly because of the following reasons-
- It overcomes the growing problem of plastic waste disposal in the country. Since a large amount of plastic waste is required for a small stretch of road, the amount of waste plastic strewn around gets tremendously reduced.
- This road construction process is eco-friendly with no toxic gases being released.
What is biodegradable waste? Name two useful products which can be made from biodegradable domestic waste.
Waste which is organic in nature and can be decomposed or broken down by living organisms is called biodegradable waste. For example- stale food, rotten fruits and vegetables etc.
Two useful products which can be made from biodegradable domestic waste are compost and biogas.
What service is indirectly done by the rag-pickers for the disposal of waste?
The poor rag pickers make a living by sorting out reusable and recyclable items from discarded solids. They do a good job by removing much of the waste from the garbage dumps. Pieces of metal, glass, rubber, plastics etc., are removed to be recycled to get finished products. Thus, they segregate the waste and make waste disposal easier.
State three steps that should be taken by the municipal authorities for the safe disposal of solid waste.
The following three steps should be taken by the municipal authorities for the safe disposal of solid waste-
- Organising house to house collection of municipal solid wastes.
- Biomedical waste and industrial waste should not be mixed with municipal solid waste. The waste should be segregated into biodegradable and non-biodegradable.
- Stray animals should not be allowed to move around waste disposal facilities.
What is composting? Give two advantages of using compost.
Composting of waste in an aerobic method of decomposing solid wastes. The organic wastes from households are made to undergo decomposition in such a way that bacteria and other micro-organisms break them down and produce a safe, clean and soil like material called compost.
Two advantages of using compost are-
- It enhances soil nutrients and water retention capacity of soil.
- It suppresses plant diseases.
What are the three R's of waste management?
The three R's of waste management are-
- Reducing the waste
- Reusing the waste
- Recycling the waste
Explain how reusing waste can reduce the burden of waste disposal.
One way to prevent waste generation, improve our communities, and increase the material well-being of our citizens is to take useful products discarded by those who no longer want or need them and provide them to those who do.
Reusing an item means that it continues to be a valuable, useful, productive item, and replaces new items that would utilize more water, energy, timber, petroleum, and other limited natural resources in their manufacture. For example, instead of discarding old or torn shoes, they can be given to under-privileged or poor people for use.
Hence, if we reuse products, we ultimately avoid the generation of waste and reduce the burden of waste disposal.
What is meant by recycling of waste effectively? Give one example.
Recycling is a process by which wastes are converted into reusable products, thereby reducing the usage of raw material and energy and controlling air, water and soil pollution.
Recycling of waste effectively means to recycle an item till it cannot be recycled further and cannot be utilised any more.
For example, in India, we have tonnes of bagasse from sugarcane during a particular season. Bagasse is used in the manufacture of paper pulp and this helps to save trees which are normally used for making paper pulp.
Give a reason for each of the following:
(i) Recycling of waste to produce paper can reduce deforestation.
(ii) Sugarcane waste can be recycled into useful products.
(iii) We should avoid using polythene carry bags.
(i) Recycling of waste to produce paper can reduce deforestation as in India, we have tonnes of bagasse from sugarcane during a particular season. Bagasse is used in the manufacture of paper pulp and this helps to save trees which are normally used for making paper pulp.
(ii) Bagasse is a waste product from the sugar industry. In India, we have tonnes of bagasse from sugarcane during a particular season. Bagasse is used in the manufacture of paper pulp and this helps to save trees which are normally used for making paper pulp. Bagasse is also used for making packaging material for dairy products. Hence, sugarcane waste can be recycled into useful products.
(iii) We should avoid using polythene carry bags because plastic is non-biodegradable. Plastic has to be incinerated, recycled or buried in landfills. The polythene carry bags are made from recycled plastic. They are harmful because the melting of plastic and plastic products breaks some polymer chains into smaller units which are harmful.