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Dumping of solid waste: a threat to environment
Environmental pollution is tangled with the unsustainable anthropogenic activities, resulting in substantial public health problems. Land pollution is one of the major forms of environmental catastrophe our world is facing today.
Enormous amounts of solid waste are being produced by the dwellers of the urban areas owing to population growth and economic development. This municipal solid waste normally termed as “garbage”, “trash” or “refuse” is an inevitable by product of human activity which is disposed through dumping, burning and burial — the three basic methods of garbage disposal used since antiquity. Solid waste land filling is the most common method of solid waste disposal worldwide. Since it is the most prevalent management option, land disposal presents the greatest environmental challenges internationally. Landfills can be classified into three general categories: (1) open dumps; (2) control dumps; and (3) sanitary landfills.
Disposal sites, which are planned, designed and constructed according to good engineering practice, and operated so that they cause the minimum environmental impact, are usually called sanitary landfills.
In developing countries open dumpsites are common, due to the low operating costs and lack of expertise and equipment. Contamination of ground water is the major environmental risk related to unsanitary landfilling of solid waste. Abandoned dumps with no systems for leachate collection have been identified in many countries as a significant threat to groundwater resources. Open dumps are unsightly, unsanitary, and generally smelly; they attract scavenging animals, rats, insects, pigs and other pests. Surface water percolating through the trash can dissolve out or leach, harmful chemicals that are then carried away from the dumpsites in surface or subsurface runoff. Among these chemicals heavy metals are particularly insidious and lead to the phenomenon of bioaccumulation and biomagnification. These heavy metals may constitute an environmental problem, if the leachate migrates into surface water or ground water.
The impact of heavy metal contamination in ecological material is based on their potential for adverse effect on human health and environment. As far as Pakistan is concern solid waste disposal is a crucial problem in most of the cities.
According to the National Conservation Strategy (NCS) Pakistan generates 47,920 tons of solid waste per day. Out of the total waste produced in Pakistan everyday, 19,920 tons is produced in urban and 28,730 tons is produced in the rural areas. Unfortunately there is no proper solid waste management system if any city of Pakistan. Islamabad, though a planned city is also facing a sever problem of municipal solid waste disposal due to lack of sanitary landfills. According to a study conducted by CDA (2002), the present per capita rate of solid waste generation in Islamabad is estimated as 0.662-kg/ capita/day, which works out to be 563 metric tons per day and 194,394 tons per year.
At present solid waste is dumped at sector H-12 where the open dumping is haphazard and without any sanitary considerations. This H-12 open dumpsite is located at a distance of about 10km from zero point owards Golra toll tax on Kashmir Highway. It is about half kilometer off the Kashmir Highway. The garbage is set on fire to control the odor and flies but a nauseating affect and stinking smell even then being generated can be felt while moving on the highway. Scavenging Afghan children used to collect recycleable materials that can be sold out. A number of families live adjacent to the landfill in tents and are indulged in the garbage collection business.
The present solid waste management in Islamabad at H-12 dumpsite is not according the environmental standards. There is a dire need for a sanitary landfill to manage the present alarming situation. The aggravating situation can be improved be taking the following steps:
1. The current system of municipal solid waste management is by no means according to environmental standards and sanitary landfill is inevitable.
2. If sanitary landfill cannot be materialized with in the near future precautionary measures such as ground cover of not less than six inches should be applied on weekly basis. This practice will dilute the noxious effects of open garbage dumping.
3. Regular monitoring of tube wells near the MSW landfill site should be done and inhabitants using that drinking water should be informed about the water quality.
4. The garbage is often put on fire which cause environmental pollution particularly air pollution, this practice should be halted.
5. The encroachment made by Afghan families at the landfill site should be restrained. Fencing of landfill site should be done to control the scavenging livestock, which feed on the hazardous material.
The writer is an M. Phil scholar of Environmental Biology, Department of Biological Sciences, Quaid-i-Azam University, Islamabad
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