Solid waste refers to all non-liquid wastes that include Solid as well as semi-solid wastes, but excluding Human and Animal excreta.
Solid waste can create very serious health problems and an unpleasant living environment if not disposed of in a proper and a safe manner, such waste may then also provide breeding sites for insect-vectors, pests, snakes and vermin that increase the risk of disease transmission. It may also pollute water sources and the environment.
Different categories of solid waste include:
- Organic waste: Food waste, Market associated wastes etc.
- Dead animals: Carcasses of animals (Cows, Buffaloes, Dogs etc.)
- Combustibles: Paper, wood, dried leaves etc. (high organic and low moisture content) Non-combustibles: Metal, tin cans, bottles, etc.
- Ashes: Residue from fires used for cooking.
- Bulky waste: Tree branches, tyres, etc.
- Hazardous waste: Battery acid, medical waste etc.
- Construction waste: Roofing, broken concrete, etc.
Factors behind the generation of Solid Waste
Solid wastes are generated from Rural as well as Urban areas in India.
The main factors affecting these are:
- Geographical Industrially and technologically developed regions like Delhi, Bengaluru generate more solid wastes when compared with less industrialized places like Shimla or Kashmir.
- Socio-cultural practices such as dumping waste in rivers, performing rituals which generate a lot of solid wastes.
- The packaging of food items use of packaged food items, that too more often, leads to generation of solid waste.
- It is seen that the volume of waste generated is likely to be small and degradable where the population is of rural origin while the urban populations are more likely to generate larger volumes of non-degradable waste, especially where packaged food is consumed more.
The Present Scenario
- Most of the dumpsites of megacities have reached way beyond their capacity and permissible height limit of 20 meters. It is estimated that more than 10,000 hectares of urban land are locked in these dumpsites in India.
- The per capita waste generation in Indian cities ranges from 200 grams to 600 grams per day.
- Only about 75-80% of the municipal waste gets collected and only 22-28 % of this waste is processed and treated.
India generates the most waste globally, and by 2050, our waste generation will double:
- Drains and water bodies, emptying out into Indian rivers, also carry with them an unimaginable amount of waste.
- The Ganga is among the top 10 polluted rivers in the world, together accounting for 90% of the total ocean plastic pollution.
- India faces a seemingly insurmountable challenge of treating and getting rid of the legacy waste, with simultaneous and continuous accumulation of fresh everyday waste.
- Central, state, city and municipal governments, over decades, have not been able to prevent this situation, nor deal with its scale.
- For a country the size of India, there are about 92 large WTE plants. Of these, only a small fraction is operational, and the plants that are operational, run at suboptimal capacity.
- State governments have, so far, invested an estimated Rs 10,000 crore in such plants.
- The task now is to be clear on what needs to be done, on what has not been done, or done incorrectly, and to ensure correct execution of a national mission.
- The proliferation of airless open dumps of garbage leads to emissions of methane, which absorbs the sun’s heat, warms the atmosphere and contributes to global warming.
- Leachate, which is a black liquid oozing out from the waste as it slowly decomposes over a period of 25 to 30 years, contaminates soil and groundwater.
- Foul odour from the waste rotting in airless heaps, and smoke from the fires that routinely erupt in them, are other consequences of dumping waste in the open.
- The earlier landfills are without bottom liners and sideliners, which allows the Leachate to seep into the ground causing groundwater and land pollution.
- The dumpsites being open and easily accessible, have become a site for further dumping by the public aggravating the situation.
Some of the major issues concerning solid waste management are:
- Absence of segregationof waste at source
- Lack of fundsfor waste management at ULBs
- Lack of technical expertise and appropriate institutional arrangement
- Unwillingness of ULBsto introduce proper collection, segregation, transportation and treatment/disposal systems
- Indifference of citizens towards waste management due to lack of awareness
- Lack of community participation towards waste management and hygienic conditions
- Lack ofsewage management plan.
- Spread of Diseases: Decomposing solid waste attracts animals, mosquitoes, vermin and flies. They play a major role in the transmission of faecal-oral diseases and the transmission of diseases such as leptospirosis, typhoid, dengue, yellow fevers, microfilariae, gastro-enteritis, dysentery and other illnesses.
Water, Soil and Air Pollution
- Poor management of the collection and disposal of solid waste may lead to Water Pollution (pollution of surface water/groundwater).
- This may also result in deterioration of Soil (Soil Pollution).
- Where large quantities of Solid dry waste are stored in hot climates this may create a fire hazard. Related hazards include Air pollution and fire threat to surrounding buildings and people.
MANAGEMENT OF SOLID WASTE
- Solid waste management can be divided into four key components: Generation Storage and Collection Transportation Disposal
- Generation of solid waste is the stage at which materials become of no use to the owner and they wish to get rid of them.
- Storage and Collection
- Storage takes place after the materials have been discarded. Key here is to not discard items directly into family pits and poorly defined heaps close to dwelling areas, but an effective storage system must be at place, like the Government of India has directed municipal corporations to undertake Door to Door collection of Solid wastes under JawaharLal Nehru National Urban Renewal Mission (JNNURM).
- Whereas under Swacch Bharat Abhiyan, two different dustbins have been provided (Blue and Green Dustbins) which are used to segregate two different kinds of wastes, the green is meant for wet wastes while the blue one is for Solid dry waste.
- This is the stage when solid waste is transported to the final disposal site. There are various modes and methods which may be adopted depending upon availability and the volume of waste to be transported.
- In India, Solid wastes are generally transported first by small municipal vehicles to a dumping site, then big municipal vehicles carry them for final disposal, be it to landfills or to recycling plants.
The final stage of solid waste management is safe disposal where associated risks are minimised. There are six main methods for the disposal of solid waste:
- Land application: Open dumps or landfilling, Open dumps and landfills are uncovered/covered areas that are used to dump solid waste of all kinds. The waste is not treated nor it is segregated and thus it is also a place where a lot of insects and other disease causing organisms breed.They are generally located in urban areas. For landfills, a pit is dug where garbage is dumped and the pit is covered with soil everyday thus preventing the breeding of flies and rats.Open dumps are more harmful than landfills as landfills after they are full can be used as a park/parking lot after covering it, but open dumps cannot be treated as such.
- Composting: Composting is a biological process in which micro-organisms such as fungi or bacteria decompose in the presence of oxygen the degradable organic wastes.The finished product is very rich in carbon and nitrogen thus acting as a great medium for plant cultivation.
- Burning or incineration: The process of burning solid wastes in a large furnace at a very high temperature whereby producing ash is called Incineration. It is only used as a last resort because it also produces a lot of toxic gases resulting in Air Pollution.
- Pyrolysis: The process of burning solid wastes, but in the absence of oxygen in a large furnace at a very high temperature whereby producing charcoal, tar, methyl alcohol, acetic acid, acetone which can be used as fuels is called Pyrolysis.
- Vermiculture:It is also known as Earthworm farming. In this method, Earthworms are added to the compost. These worms break the solid waste and along with the earthworms excreta, the compost becomes rich in nutrients.
- Recycling: Solid wastes are also recycled, where the solid wastes are first taken to compost plants which are either set up by Government or by Private companies (under Corporate Social Responsibility), then they are either converted to fertilizers or they are recycled to produce various other items such as Plastics bottles, electronic instruments, building materials etc.
Legislation in India
- Solid Waste Management Rules 2016:
- These rules replace the Municipal Solid Wastes (Management and Handling) Rules, 2000, are now applicable beyond municipal areas and have included urban agglomerations, census towns, notified industrial townships etc.
- They focus on segregation of waste at source, responsibility on the manufacturer to dispose of sanitary and packaging wastes, user fees for collection, disposal and processing from the bulk generator.
- It has also been advised that the bio-degradable waste should be processed, treated and disposed of through composting or bio-methanation within the premises as far as possible and the residual waste shall be given to the waste collectors or agency as directed by the local authority.
- The rules promote the use of compost, conversion of waste into energy, revision of parameters for landfills location and capacity.
- The government has also constituted a Central Monitoring Committee under the chairmanship of Secretary, MoEF&CC to monitor the overall implementation of the rules.
- The Rules for the Safe Treatment of Legacy Waste prescribe bio-remediation and bio-mining in all open dumpsites and existing operational dumpsites in India.
- Apart from this, Article 51 A (g) of the Constitution of India makes it a fundamental duty of every citizen of India to protect and improve the natural environment including forests, lakes, rivers, and wildlife, and to have compassion for living creatures.
What are the current modes of challenges in waste disposal challenges associated with them?
- Waste-to-energy (WtE) plants which rely on the incineration of mixed waste
- WtE plants in India burn mixed waste. The presence of chlorinated hydrocarbons like PVC results in the release of dioxins and furans when the waste is burnt at less than 850 degree Celsius
- Harmful emissions: Dioxins and furans are known to be carcinogenic and can lead to impairment of immune, endocrine, nervous and reproductive systems.
- Poor compliance: These WtE are not in compliance with guidelines given by the National Green Tribunal.
- Environmentally unsustainable : Even when incineration takes place under optimal conditions, large amounts of flue gases, mercury vapour and lead compounds are released, and there is always about 30 per cent residue from incineration in the form of slag (bottom ash) and fly ash (particulate matter), which are also known to be serious pollutants of air and water.
- Also, WtE plants in India are also inefficient in generating energy.Municipal waste in India has a very high biodegradable (wet) waste content ranging anywhere between 60 to 70 % of the total, compared with 30 % in the Western countries. This gives our waste high moisture content and low calorific value.
- Compactors are expensive machines that squeeze and compress the volume of waste, this enables more waste to be carried per trip and, thus, reduces transportation costs.
- The antithesis of segregation: The use of compactors on mixed waste makes it almost impossible to extract the recyclable dry waste such as plastics, metal, paper and cardboard from the mixture.
- Polluting: The compression of wet waste in the mixture releases leachate (a black foul-smelling liquid) that is difficult to dispose of. Leachate percolates into the soil and contaminates groundwater. When it drains off into the sewer system, it overloads the sewage treatment plants.
- Increases global warming: After the compacted waste is transported and dumped, the lack of aeration at the site results in the decomposing wet waste generating methane, a potent greenhouse gas that causes global warming.
- Waste transport contracts with private parties
- A payment for waste transportation is made on a tonnage basis.
- This provides an incentive to maximize the weight of waste.
- These private players mix whatever the waste is given to them separately.
- Also, the unmixed transportation and processing of wet and dry waste encourage citizens to keep their waste unmixed too.
Cleaning up the mess: the need for a waste management policy
In India, less than 60% of waste is collected from households and only 15% of urban waste is processed.
Hyperconsumption is a curse of our modern times. Humans generate monumental amounts of waste, a sizeable portion of which is disposed in landfills and through waste-to-energy incinerators.
However, billions of tonnes of garbage, including microplastics, never make it to landfills or incinerators and end up in the oceans.
This garbage chokes marine life and disturbs zooplankton, which are vital to the elimination of carbon dioxide from the atmosphere.
To understand the existing scenario of waste management, impact of poor waste management solutions, policies that have been framed to address it and the major systemic changes that need to happen to ensure this important public issue does not turn into a national calamity.
Problems of unscientific MSW disposal:
Only about 75- 80% of the municipal waste gets collected and out of this only 22-28 % is processed and treated and remaining is disposed of indiscriminately at dump yards.
It is projected that by the year 2031 the MSW generation shall increase to 165 million tonnes and to 436 million tons by 2050.
If cities continue to dump the waste at present rate without treatment, it will need 1240 hectares of land per year and with projected generation of 165 million tons of waste by 2031, the requirement of setting up of land fil for 20 years of 10 meters height will require 66,000 hectares of land.
Scientific disposal of solid waste through segregation, collection and treatment and disposal in an environmentally sound manner minimises the adverse impact on the environment.
The local authorities are responsible for the development of infrastructure for collection, storage, segregation, transportation, processing and disposal of MSW.
If municipal solid waste management is done through proper planning and management, it would lead to a business case of income generation and provide financial support to ULBs by generating revenue.
There are several problems in India in how waste is treated:
First, segregation of waste into organic, recyclable and hazardous categories is not enforced at source.
As a result, mixed waste lands up in the landfills, where waste-pickers, in hazardous conditions, try to salvage the recyclables, which are of poor quality and quantity by then.
Second, ideally, waste management should not be offered free of cost to residents.
Only if residents pay will they realise the importance of segregation and recycling.
Third, there is the issue of logistical contractors who are motivated to dump more garbage in landfills as their compensation is proportional to the tonnage of waste.
They are also prone to illegally dump waste at unauthorised sites to reduce transportation costs.
Fourth, and importantly, organic farming and composting are not economically attractive to the Indian farmer, as chemical pesticides are heavily subsidised, and the compost is not efficiently marketed.
There are solutions to the garbage pandemic through the crucial processes of material recycling and composting.
Efficient composting is possible through an optimal combination of microbes and temperature to produce a nutrient-dense soil conditioner.
- There is a need for a comprehensive waste management policy that stresses the need for decentralised garbage disposal practices as this will incentivise private players to participate.
- It is important that Biomining and Bioremediation are made compulsory for areas wherever they can be applied.
- To overhaul the waste management sector and induce the necessary behavioural change, citizen participation and engagement is the key.
- Waste segregation practice can be inculcated in the masses through an awareness-building programme accompanied by a fine if mixed waste is handed out.
- The Ministry of Housing and Urban Affairs should either stop financing compactors or at least offer municipalities similar levels of support for more sustainable methods of waste management. For example, access to bio-composters in residential localities.
- A much smarter alternative for municipalities under the Smart Cities Mission would be to promote decentralised composting of wet waste, tie-up with local “kabadiwalas” or NGOs for recyclable dry waste, and work on safe disposal of the rest.
- The savings from eliminating costly secondary transport can easily fund the construction and operation of decentralised centres for the processing of wet and dry waste.
1) What are various urban wastes? What are the different steps involved in solid waste management in municipal areas? Elaborate upon the major problems faced due to urban waste dumping sites. (250 words)
2) Discuss in detail the issues and challenges involved in India’s waste Management system also explain in what way India’s Smart Cities Mission is creating new opportunities for better management of wastes.(250 words)