A Preliminary Assessment Of The Impact Of Solid Wastes On Soils And Groundwater System In Parts Of Port Harcourt City And Its Environs, Rivers State, Nigeria

Soil and groundwater samples from four refuse dumpsite locations in Port Harcourt city and its environs were studied to assess the impact of solid wastes on soils and groundwater system in the area. The study shows significant abundances of Cu, Pb, Zn in soils, in the following ranges Cu: 0.0055-2.31%, Pb: 0.002-3.08%, and Zn 0.001-1.93%. This shows that the soils are contaminated to hazardous levels when compared with acceptable standards. The concentrations of these metals are found to decrease with depth in the soils. However, groundwater in the area is potable and not polluted by the chemical species studied (pH, Fe, Zn, Cd, Cu, Pb, Mn, Cl and N03). It also shows low levels of BOD, COD, TDS, Hardness and coliforms. The metal enrichments in the soils owe their origin to the refuse dumps as well as other sources like dissolution from parent rocks, buried oil pipes and fuel reservoirs, geochemical processes operating within the groundwater system, and atmospheric precipitation. The tolerable concentrations of the parameters in groundwater can be explained by the geologic control on the movement of chemical species in the soils. KEY WORDS: Solid waste, impact, soil, groundwater, Port Harcourt. Global Journal of Environmental Sciences Vol.4(1) 2005: 23-3

Hydrogeophysics: An overview of general concepts, applications and future perspectives

Hydrogeophysics is an emerging discipline that holds great promise in characterizing hydrogeological parameters and processes. A tight collaboration between hydrogeologists and geophysicists is necessary to achieve the most appropriate use of geophysics in hydrogeology, mainly for planning the geophysical activities in accordance to the hydrogeological target to be investigated and for the interpretation or translation of the geophysical documents into hydrogeological documents. For this collaboration to be meaningful, it is of great importance to share a common language allowing communication feasible: geophysicists have to know the fundamentals of the hydrogeological process, and hydrogeologists have to know the fundamentals of geophysical methods. This is basically the main objective of this paper, where fundamental concepts of both disciplines, their contributions, the methods available, data integration approaches, and future perspectives as well as the hydrogeophysical challenges are presented. Key words: hydrogeophysics, geophysics, hydrogeology, surface geophysics and hydrogeophysical method

Groundwater Protection As Viable Option For Sustainable Water Supply In Nigeria

The threat of contamination of groundwater due to indiscriminate refuse disposal, bad management of sewage and septic tanks, industrial effluent discharges, leakage of underground fuel pipes and storage tanks and non-point pollution sources in major urban and semi- urban locations across the country are real. The argument to start planning for groundwater protection before there is serious contamination is clear and powerful. Such preventive action is the essence of groundwater protection. The logic of preventing groundwater contamination is clear but our problem or concern is in remediation of groundwater contamination. Although there are many well documented examples of groundwater remediation and good sources of information on how to clean up contaminated aquifers, the need to protect our groundwater supplies cannot be over emphasized. The age long aphorism “ prevention is better than cure” applies here. This is because, once polluted, groundwater supplies are difficult and expensive to purify and the aquifer requires a long time to “heal” naturally. It then constitutes a health hazard to the consumers. This paper therefore addresses the question of how we can protect groundwater from becoming polluted. The paper not only concentrates on the problems of protecting groundwater from toxic chemicals but also discusses ways of protecting groundwater from conventional pollutants. Keywords:Groundwater protection, contamination, pollution, sustainable water supply, Nigeria. Global Journal of Geological Sciences Vol. 6 (2) 2008: pp. 153-15

Evaluation of hydrochemical characteristics and flow directions of groundwater quality in Udi Local Government Area Enugu State, Nigeria

A hydrogeological study was conducted at the Udi Local Government Area in south-eastern region of Nigeria to examine the hydrochemical constituent of groundwater and determine the quality for drinking and agricultural purposes. Results show that groundwater in the area is slightly acidic to slightly basic, soft and potable, when compared with the World Health Organisation standards for drinking water, and is suitable for agricultural purposes. The groundwater flow direction was determined to establish the implications of pollution from any water contamination. Twenty-one groundwater samples from existing boreholes were collected and analysed for various physicochemical parameters using standard field and laboratory techniques. Distribution of major ions was plotted on a Trilinear Piper diagram. Ajali Sandstone, known as major aquiferous layer in the area, outcrops predominately in sandy bed with medium to coarse-grained sediments. The aquifers are unconfined, semi-confined and with hydraulic conductivity values ranging from 9.0 x 10(-2) to 8.5 x 10(-2) m/day indicating medium transmissivity of groundwater in some areas and a flow net south to northward groundwater flow towards the coast. This explains why the aquifer does not appear to be very permeable and only provides a medium yield of good quality water in some regions of the study area

Inpatient length of stay: a finite mixture modeling analysis

Finite mixture modeling, Inpatient length of stay, Heterogeneity, C5,