IMPACT OF SANITARY LANDFILLS TOWARDS SUSTAINABLE DEVELOPMENT IN NIGERIA
CHAPTER ONE
INTRODUCTION
1.1 Background of Study
In terms of Sustainability and environment, the natural elements play important roles for ecological preservation. Water is the most abundant environmental resource on earth but its accessibility is based on quality and quantity, as well as space and time. It may be available in various forms and quantity but its use for various purposes is the subject of quality. About 70% of the human body and about 60-70% of plant cells is made up of water (Smith and Edger, 2006). It is one of the determinants of human settlement, existence and activities on the earth. Its quantity is fixed but dynamic in formation and storage. Of all the environmental concerns that developing countries face, the lack of adequate, good quality water remains the most serious (Markandya, 2004). Once contaminated, groundwater may forever remain polluted without remedy or treatment. Water is one of the determinants of human earth system. Diseases may spring up through water pollution, especially groundwater contamination, and rapidly spread beyond human expectation because of its flow mechanism (Afolayan et al., 2012). One of the major factors that make the earth habitable for humans is the presence of water. Forming the major component of plant and animal cells, it is the basis of life and therefore the development of water resources is an important component in the integrated development of any area.
Water is critical to our daily lives and is an extraordinary compound in nature. It covers 71% of Earth (USGS, 2014). Water is the most important resource of a country, and of the entire society, since no life is possible without water. It has this unique position among other natural resources, because a country can survive in the absence of any other resource, except water (Garg, 2009). According to the National Water Policy (2002), in the planning and operation of systems, water allocation priorities should be broadly as follows: drinking, irrigation, hydropower, ecology, agro-industries and non-agricultural industries, navigation and other uses.
About 68.7% of the fresh water is tied up in polar ice caps and glaciers, and a further 30.1% is underground as groundwater, most of which is not available for use (Gleick, 1996). Rivers and lakes constitute a mere 0.32%, atmospheric moisture 0.03% and soil moisture 0.05%.The major sources of water are surface water (oceans, rivers, streams, seas and brooks), groundwater, snow and ice, and lakes. However their exploration and exploitation varies from place to place based on their state of existence. Groundwater plays a vital role for urban and agricultural water supply. It accounts for about 0.5% of total hydrosphere, approximately 6.73 x10km3 in volume (Ayoade, 2003). It constitutes a major portion of the earth’s water circulatory system known as hydrological cycle and occurs in permeable geologic formation known as aquifers i.e. formations having structure that can store and transmit water at rates fast enough to supply reasonable amounts to wells (Afolayan et al., 2012).
Wastes of different types, mostly solid wastes are the major input of dumpsites/landfills. With respect to the hydrological analysis of groundwater, it flows from areas of higher topography towards areas of lower topography, thereby bringing about the examination of the degradable material which form leachate and contaminate the groundwater of the study area.
Landfill practice is the disposal of solid wastes by infilling depressions on land. The depressions into which solid wastes are often dumped include valleys (abandoned) sites of quarries, excavations, or sometimes a selected portion within the residential and commercial areas in many urban settlements where the capacity to collect, process, dispose of, or re-use solid waste in a cost-efficient, safe manner is often limited. The practice of landfill system as a method of waste disposal in many developing countries is usually far from standard recommendations (Mull, 2005; Adewole, 2009; Eludoyin & Oyeku, 2010). A standardized landfill system involves carefully selected location, and is usually constructed and maintained by means of engineering techniques, ensuring minimized pollution of air, water and soil and risks to man and animals. It involves placing waste in lined pit or a mound (Sanitary landfills) with appropriate means of leachate and landfill gas control (Alloway & Ayres 1997; Eludoyin & Oyeku 2010). Land filling of municipal solid waste is a common waste management practice and one of the cheapest methods for organized waste management in many parts of the world (El-Fadel et al., 1997; Jhamanani et al., 2009; Longe & Balogun, 2010). Increasing urbanization results in an increased generation of waste materials and landfills become the most convenient way of disposal. Most of these landfills are mere ‘holes in the ground” do not qualify as sanitary means of solid waste disposal. Most of the areas around the Solous dumpsites depend either on dug-up wells or bore-holes which may likely be affected by the generated leachate through waste decomposition from the dumpsites despite the provision of pipe-borne water by government. According to Papadopoulou et al. 2007, as the natural environment can no longer digest the produced wastes, the development of solid waste management has contributed to their automated collection, treatment and disposal. One of the most common waste disposal methods is landfilling, a controlled method of disposing solid wastes on land with the dual purpose of eliminating public health and environmental hazards and minimizing nuisances without contaminating surface or subsurface water resource.
There are three major landfills and two temporary landfill sites serving the area of Lagos State. The Olushosun landfill site is the largest, situated in the Northern part of Lagos within Ikeja Local Government Area, and receives approximately 40% of total waste deposits from Lagos (LAWMA, 2011).
