Waste evaluation options in India

Waste evaluation options in India

The problem of municipal solid waste management has acquired alarming dimensions in India especially over the last decade, before which waste management was hardly considered an issue of concern as the waste could be easily disposed of in an environmentally safe manner.

The physical and chemical characteristics of Indian city refuse, nonetheless, show that about 80% of it is compostable and ideal for biogas generation due to adequate nutrients (NPK), moisture content of 50-55% and a carbon-to-nitrogen ratio of 25-40:1. Therefore, the development of appropriate technologies for utilisation of wastes is essential to minimize adverse health and environmental consequences. Against this backdrop, let us discuss below the quantum of wastes generated in India,  their  composition,  disposal methods, recycling aspects, and health  and environment impacts:

(i)          Waste  quantum:  The  per  capita  waste  generation  rate  is  about  500 g/day.

This  along  with  increased  population  has  contributed  to  higher  total  waste

generation quantum.

(ii)                       Waste composition: Studies reveal that the percentage  of the organic matter  has

remained almost static at 41% in the past 3 decades, but the recyclables have increased from 9.56% to 17.18%.

Garbage  in  Indian  cities  is  estimated  to  contain  about  45-75%  biodegradable waste

(as against 25% of US city-garbage) with 50-55% moisture; 35-45% being fruits, vegetable and food biomass; and 8-15% non organic materials like plastic, metal, glass, stones, etc. Refuse from Indian cities also contains high organic and low combustible matter, if the studies carried out in six cities are of any indication.

(iii)                    Waste disposal methods: Waste disposal is the final stage of the waste management cycle. About 90% of the municipal waste collected by the civic authorities in India is dumped in low-lying areas outside the city/town limits, which have no provision of leachate collection and treatment, and landfill gas collection and use.

(iv)                    Recycling: This involves collection of recyclables from various sources, which ultimately reach recycling units. It is estimated that about 40-80% of plastic waste gets recycled in India, as compared to 10-15% in the developed nations of the world. However, due to lack of suitable government policies, incentives,

subsidies, regulations, standards, etc., related to recycling, this industry is still far behind itswestern counterparts in terms of technology and quality of manufactured goods. Nevertheless, recycling in India is a highly organised and profit-making venture, though informal in nature.

(v)                       Health impacts: Due to the absence of standards and norms for handling municipal wastes, municipal workers suffer occupational health hazards of waste handling. At

the dumpsites in the city of Mumbai, for example, 95 workers were examined and it was found that about 80% of them had eye problems, 73% respiratory ailments,  51% gastro intestinal ailments  and  27%  skin  lesions. Also, municipal workers and rag  pickers who  operate  informally for  long hours rummaging through waste also suffer from similar occupational health diseases ranging from  respiratory illnesses (from ingesting particulates and bio-aerosols), infections (direct contact with contaminated material), puncture wounds (leading to tetanus, hepatitis and HIV infection) to headaches and nausea, etc. Studies among the 180 rag pickers at open dumps of Kolkata city reveal that average quarterly incidence of diarrhoea was 85%, fever 72% and cough and cold 63%.