1.0 Introduction
1.1 Background of Study
The sustenance of life depends greatly on water, therefore, the demand for potable water increases continually in line with world populationgrowth. Recently, many African cities have undergone unprecedented growth in population through migration from rural areas which has led to the growth of cities into sprawling “mega-cities” with large areas of unplanned sub-standard housing with few services. The unplanned expansion of such cities leads to a serious pollution threat to the groundwater and uncontrolled industrial and commercial activity add to the pollution threat (UNEP, 2002). This has been a major problem in developing countries; provision of drinking water has become expensive and difficult.
The main source of potable water in many of these cities is groundwater, commonly from shallow hand-dug wells and deeper water supply boreholes. In Nigeria, like many other developing countries, open waste dumping system has been the major management option of solid waste disposal. In previous years, management system has been based on collection and dumping out of the city boundaries in conformity with the concept of “out of sight out of mind” (Arukweet al, 2012). But in recent times, the siting and development of residential quarters near waste sites are common due to shortage of building land to cope with the increasing rate of migration and consequent population explosion (Ikemet al., 2002).
Dumpsites have been identified as one of the major threats to soil and water resources, receiving a mixture of municipal, commercial and mixed industrial wastes. The depressions into which solid wastes are often dumped include valleys and excavations. Studies on the effects of unlined waste dumps on the host soil andunderlying shallow aquifers have shown that soil and groundwater system can be polluted due to poorly designed waste disposal facilities (Amadiet al., 2012). Uncontrolled waste dumpsites threaten the groundwater supply as movement of leachates from dumpsites through the soil and the aquifers pose a risk to the environment and human health. Waste placed in dumpsites or open dumps are subjected to groundwater underflowor infiltration from precipitation (Moret al., 2006). The presence and potential exposuresof the community to groundwater contaminants may contribute to the predilection of human health impacts, from simple poisoning to cancer, heart diseases and teratogenicabnormalities (Su, 2008).
Release of pollutants through leachates from both functional and abandoned dumpsites pose a high risk to nearby soil and groundwater if not adequately managed (Ikemet al., 2002). Leachate percolating into the groundwater is a mixture of highly complex contaminants such as potentially toxic metals(lead, mercury, cadmium, chromium etc) ; persistent organic pollutants (POPs) (dioxins, furans, polycyclic aromatic hydrocarbons (PAHs), polybrominateddiphenyl ethers PBDEs); inorganiccompounds (such as ammonium, sulphates, chlorides) and as well as bacterial contamination — total coliform and feacal coliform (Moret al., 2006; Longe and Balogun, 2010; Oyeku and Eludoyin, 2010; Agrawaetal., 2011 and Galarpe and Parilla, 2012). Therefore considering possible impact to surrounding environment brought by dumpsites is inevitable.
Despite the enormous resources and efforts that have been committed to waste management, refuse collection and disposal remains a major problem in Kaduna metropolis. Kaduna is one of the most populous cities in Nigeria; hence enormous pressure is put on the environment due to huge amounts of solidwaste generated daily.
The residents make a heavy demand on resources and at the same time, generate large quantities of solid waste. Generally, these wastes are not treated; they are transferred to the several dumpsites, where they are openly burnt. The overwhelming environmental significance and impact of leachates on soil and nearby groundwater and surface water has becomea great concern because of its serious threat to the quality of life of human beings that depends largely on water to sustain their livelihood.
Kaduna and its environs is littered with several dumpsites among which are those located atKurminMashi, Kakuri, SabonGari and Tudun Wada. Thisresearch work is to cover that of Tudun Wada as a result of its proximity to the residential houses, the population density of the area and also its old age of waste accumulation. Therefore, soil samples and groundwater from Tudun Wada around a dumpsite are assessed for the level of soil pollution and groundwater contamination through leachates percolation from the dumpsite.
1.2 Statement of the Problem
Environmental impact assessment of potential health hazards facilities on their immediate environment ought to be a routine exercise by appropriate bodies such as KEPA to proactively prevent outbreak of preventable diseases. However, the unprecedented rate of growth of such facilities in Kaduna is so overwhelming, thereby requiring the intervention of unsolicited but enlightened workers such as the academics for this routine monitoring.
1.3 Significance of the Study
Effect of extent of environmental contamination of the groundwater and immediate soil in the area of study will be established by the work. Mitigation and amelioration measures will be suggested, hence negative health issues related to water and soil pollution will be minimized as a result of the work.
1.4 Aim and objectives of the Study
The aim of this research is to assess the impacts of a refuse dumpsite in Tudun Wada, Kaduna on the quality of groundwater and arable soil within the area.
The Objectives are:
- To assess of the level of impact of the dumpsite on the quality of the immediate soil and groundwater.
- To suggest the mitigation and amelioration measures.
1.5 Scope of the study
This research is to cover the assessment of impacts of the refuse dumpsite in Tudun Wada, Kaduna on the quality of its surrounding soil and groundwater and to provide remediation and amelioration measures were the following parameters will be analyze, pH, conductivity, Totao dissolved solid, Dissolved Oxygen, Biological Oxygen Demand, Total alkalinity, Chloride content, Total hardness, Nitrate, Phosphate, Copper, Cadmium, Chromium, Iron, Lead, Zinc, Total coliform count and Hetet.
