WATER POLLUTION CAUSED BY LANDFILLS AND OPEN DUMPS

Water Pollution Caused by Landfills and Open Dumps

Water Pollution Caused by Landfills and Open Dumps

Introduction

The management of solid waste is an area of universal concern for both the developed and developing world. It is imperative that efficient, technically sound, and cost effective solid waste management solutions are developed in the near term - for the benefit of the burgeoning populations in the world's cities and the natural environments that must sustain them. This paper focuses on the Land disposal of solid waste and how current practice of open dumping could be improved to sustainable landfills in a phased manner.

Water Pollution

The present studies indicated that the quality of run off and ground water due to disposal of USW as landfill at Hyderabad indicated that the pH ranged from 8.3 to 8.8 and EC varied from 0.9 to 3.8 dSm-1.

The electrical conductivity of all the well waters including bore well waters was beyond the limits. . The total solids content of well waters ranged from 800-3500 mg l -1 . The total solids in all the wells at both the sites decreased with increase in the distance of wells from the landfill sites. The well waters up to the distance of 150 and 200 m were very much polluted in Golkonda and Amberpet sites respectively. The total dissolved solids concentration of well waters were found to be high as 2800 mg l -1 .The dissolved oxygen in well waters ranged from 4.6 to 7.4 mg l-1...The sodium content of well waters ranged from 100 to 1560 mg l-1 .The chloride contents of well waters ranged from 74 to 935 mg l -1 . The total hardness and alkalinity values were far above the prescribed ISI (1983) and WHO (1984) standards. The BOD and COD also increased beyond the prescribed limits in some wells(Jeevan Rao and shantaram.1995a,1995c).

The land disposal of solid wastes creates an important source of ground-water pollution. Most landfills throughout the world are refuse dumps. Only a few if at all can be regarded as sanitary landfills, indicating that. They were designed and constructed according to engineering specifications.The possible sources of water include precipitation, surface water infiltration, percolating water from adjacent land and ground water in contact with the fill.

Entry of pollutants into shallow aquifers occurs by percolation from ground surface, through wells, from surface waters and by saline water intrusion. The extent of pollution in ground water from a point source decreases due to natural attenuation as pollutants move away from the source until a harmless or very low concentration level is reached. Because attenuation rate varies with the nature of pollutants, the distance to which pollutants travel will vary.

A major concern with ground-water pollution is the fact that it may persist underground for years, decades or even centuries. This is in marked contrast to surface water pollution. Reclaiming polluted ground water is therefore much more difficult, time consuming and expensive compared to remediations polluted surface ...