Refuse Dump Sites Research Articles

Microbiological quality of water collected from boreholes sited near refuse dumpsites in Port Harcourt, Nigeria

5cfu/ml for near dumpsite and non-dumpsite borehole water samples, respectively, while the total coliform count ranged from 47 to 1,100 most probable number (MPN)/100 ml and 43 to 210 MPN/100 ml for near dumpsite and non-dumpsite samples, respectively. The borehole water samples from both study areas had high counts of faecal coliforms (Escherichia coli), and pathogens (Salmonella, Shigella and Vibrio spp.) were detected in high numbers in the water samples near dumpsite. Colour, pH, TDS and TSS concentrations in the near dumpsite samples were significantly different when compared to non-dumpsite water samples. Continuous water quality monitoring is encouraged to effectively analyze the impact of dumpsites on the environment and human health.

Modeling Perceived Quality of Life for People Living Near a Nigerian Dumpsite

In response to the rapid and unplanned growth that has led to the colocation of residential communities with refuse dumpsites in Lagos, Nigeria, we conducted a cross-sectional investigation of individuals living within the Olusosun community near a refuse dumpsite. Participants were 479 persons (>18 years of age, 52.6% male) who lived within 1 km of a refuse dumpsite. We examined the relationships between perceived quality of life and predictor variables, self-esteem, learned helplessness, and environmental expectations. Data analysis using structural equation modeling procedures partially supported our hypothesized explanatory model. Specifically, we found self-esteem had direct and indirect effects, through environmental expectations, on perceived quality of life. However, the indirect effect of learned helplessness on perceived quality of life was not supported. A limitation of our study, selective recruitment of participants who could read and write in English, emphasizes the need for future studies to recruit indigenous language speakers.

Integrated Geophysical Survey In A Refuse Dumpsite Of Aarada, Ogbomoso, Southwestern Nigeria.

Surface geophysical survey was conducted around Aarada refuse dumpsite, Ogbomosho, Oyo State, Nigeria to locate leachate plumes migration pathways using the very low frequency electromagnetic and vertical electrical sounding techniques. Eight VLF-EM profiles of length 70 to 150m with 10m interstation spacing and seven Vertical Electrical Soundings with current electrode separation varying from 150 to 200m were established. The analyzed VLF-EM data revealed the presence of conductive pollutants (leachate plumes) at the subsurface while the geoeletric sections generated from the processed VES data showed that the leachate plumes have actually migrated to a depth of 5.4m in the area which confirmed the VLF-EM results

Assessment of heavy metals (lead and cadmium) concentration in Paspalum orbiculare near municipal refuse dumpsites in Lagos State, Nigeria

Lead and cadmium concentrations in Paspalum orbiculare from four different dumpsites and a control site were determined in this study. The Plant samples were analyzed for lead and cadmium concentrations using a flame atomic absorption spectrophotometer (FAAS) Perkins Elmer Model 500. The presence of lead in the plant tissues obtained form the study site where burning was attributed to the high degree of correlation between foliar concentration and burning of refuse. High concentration of heavy metals can be a source of health risk to living organisms including humans in the environment. More needs to be done in the way we dispose our solid wastes to reduce environmental pollution. Key words: Pollution, heavy metals, incineration, dumpsites.

Geoelectrical Imaging at an Abandoned Waste Dump Site in Ibadan, Southwestern Nigeria

Leachate-effluent from refuse dump site is an important source of groundwater pollution. Consequently, assessing the impact of leachate is an active area of groundwater research. Geoelectrical imaging was carried out at an abandoned waste dump site in Ibadan, southwestern Nigeria, with the aim of determining how accurately electrical measurements could delineate the influx of leachate into groundwater and surface water. Eight electricalresistivity profiles were measured. Four of the traverses were conducted on the dump site whereas two traverses were measured towards the lower side to assess possible ingress of the leachate. The other two lines were measured about 300 m from the site to serve as control. Elevation data were collected using Global Positioning System. The resistivity data were inverted using the least-square technique. The inversion delineated regions of low resistivity ( 20 Ωm). The highest resistivity regions (>100 Ωm) were interpreted as regolith derived from chemical weathering of the crystalline bedrock. Resistivity-derived thickness of the leachate zone was consistent with the thickness derived from the elevation data. It could be inferred that there was high concentration of leachate towards the lower elevation hence the adjoining stream is prone to pollution. This study showed that 2D imaging can be effective in imaging pollution plumes around refuse dump sites. The method can be useful to assess opportunity for remediation measures in situations where the leachate has reached the groundwater system.

Effectiveness of 3D geoelectrical resistivity imaging using parallel 2D profiles

Acquisition geometry for 3D geoelectrical resistivity imaging in which apparent resistivity data of a set of parallel 2D profiles are collated to 3D data set was evaluated. A set of parallel 2D apparent resistivity data were generated over two model structures. The models, horst and trough structures, simulates the geological environment of a weathered profile and refuse dump site in a crystalline basement complex, respectively. The apparent resistivity data were generated for Wenner-alpha (WA), Wenner-beta (WB), Wenner-Schlumberger (WSC), dipole-dipole (DDP), pole-dipole (PDP), and pole-pole (PP) arrays with minimum electrode separations (a = 2, 4, 5 and 10 m ) and inter-line spacing (L = a, 2a, 2.5a, 4a, 5a and 10a). The 2D apparent resistivity data for each of the arrays were collated to 3D data set and inverted using a full 3D inversion code. The 3D imaging capability and resolution of the arrays for the set of parallel 2D profiles are presented. Grid orientation effects, which decrease with decreasing inter-line spacing, are observed in the inversion images. Inter-line spacing of not greater than four times the minimum electrode separation gives reasonable inverse models. The resolution of the inverse models can be greatly improved if the 3D data set is built by collating sets of orthogonal 2D profiles. Key words: Acquisition geometry, parallel 2D profiles, 3D surveys, geoelectrical resistivity, 3D imaging, inversion.

Heavy Metals in Soils of auto- mechanic shops and refuse dumpsites in Makurdi Nigeria

Dumpsites soil samples in Apir and North Bank Auto- mechanic workshop locations in Makurdi, the Benue State capital located on latitude 70 44'N and longitude 80 32’E of the Equator situated in a valley in north central Nigeria, 100m above sea level, were collected and analyzed for content of selected heavy metals. These locations were chosen for investigation, being the major mechanic workshops sites in Makurdi; and most mechanic workshop waste are made up of metals. Atomic Absorption Spectrophotometer (UnicamSolaar32 model) was used for analyzing the digested soil samples for heavy metal content. Mean concentrations of the selected heavy metals in the dumpsite soil at Apir were 0.003 mg/Kg, 0.2414 mg/Kg, 0.2552 mg/Kg, 0.1882 mg/Kg and 0.0210 mg/Kg for Cd, Cr, Cu, Pb and Ni respectively while in North bank the mean concentrations were 0.0178 mg/Kg, 0.2688 mg/Kg, 0.1869 mg/Kg, 0.5701 mg/Kg and 0.2431 mg/Kg for Cd, Cr, Cu, Pb and Ni respectively .The results from both locations were higher than their controls indicating a clear case of pollution. Heavy metals from the wastes were suspected to be the feeding source in the soils. Such a situation could be regarded as “unsafe” as these metals are eventually taken up by plants and subsequently get into the food chain. Ground and surface water quality is also threatened as these heavy metals get leached and washed into them, making the water unfit for human consumption. Advocacy of waste disposal and its effects with legislation are recommended. This study is important to the host communities of the auto-mechanic locations as a source of awareness of the environmental effects of refuse dumpsite soils. It will also form a baseline of the environmental effects of indiscriminate dumping of refuse. Previous studies have not recognized auto-mechanic shops dumpsites and it will make for research in this area. @JASEM

Modeling of 1-D nitrate transport in single layer soils

There is increasing concern on environmental pollution especially potential of groundwater contamination by nitrates. The objectives therefore were to investigate the 1-D solute transport equation for single layer soil, calibrate, verify and apply model to field condition. The transport of nitrate in laboratory single soil columns of sand, laterite and clay were investigated after 21 days. The 1-D contaminant transport model by Notodarmojo et al (1991) for single layer soils were calibrated and verified using field data collected from a refuse dump site at avu, owerri, Imo state. The experimental distribution of nitrate along the sandy soil is linear with reduction rate of 0.44 ppm/cm, slightly exponential for laterite and clay with reduction rate of 0.136 ppm/cm and 0.24 ppm/cm respectively. The results show predicted transport was in close agreement with measured values with coefficient of correlation (R) ranging from 0.9 to 0.99. Application of the results in the prediction of possibility of pollution of groundwater was very promising.Keywords: Contaminant transport, Nitrate, 1-D, column experiment

Metal levels in some refuse dump soils and plants in Ghana

Concentrations of Cd, Hg, Pb, Cr, Fe, Co, Ni, Cu, Zn, Mo and As were determined in soils and leaves of plants from refuse dumpsites and background soils in two cities, a municipality and a rural community in Ghana, using a ThermoFinnigan Element 2 high resolution inductively coupled plasma mass spectrometric (HR-ICP-MS) instrument. The refuse dump soils were classified between 'Uncontaminated to Moderate' and 'Strongly Contaminated'. Pollution levels for Cd (Igeo = 2.06–2.40) and Zn (Igeo = 2.95–3.36) were higher than of the other metals. The refuse dump soil from the rural community was the least polluted with the metals. Fe and Ni loads in plants from the refuse dump soils in the cities and the municipality were beyond the normal ranges of 40–500 µg/g (Fe) and 0.02–5.00 µg/g (Ni). Transfer ratios for Cd, Hg, Cu, Zn and Pb and Fe of plants from the background soils were higher than those from the refuse dump soils, which might be due to the higher levels of organic matter, pH, phosphate, Ca and Mg in the refuse dump soils.

English

Soil samples from four public waste dump sites (three samples from each location at 10 m interval) and plant sample (root and leave) from Igbaletere dump site were analyzed for heavy metals such as Cu, Mn, Fe, Cr, Pb, Co, Zn and Ni. On the average, high concentrations of Cu, Mn, Fe, Pb, and Zn were found in the soil samples collected at the centre of the dump sites that is, 231.55, 292.03, 158.55 and 205.40 mg/g respectively. The lower concentration was obtained in the soil samples taken at distance 20 m away from the centre of dumpsites, Mn 64.20, Fe 110.65, Pb 213.00 and Zn 66.86 mg/g respectively. The upland location of these refuse dump sites to the adjoining wells and the potential use of the dump soil for compost could cause environmental hazard. In the plant sample, concentration of Fe (341.94 mg/g) was found to be the highest in the root, while concentrations of Mn (109.69 mg/g) the highest in the leaf. The concentration of heavy metals in the roots of plant from Igbaletere dump site was correlated with the concentration of heavy metals in the soil samples from the dump site. The value of 0.9985 correlations, 0.051 alienation and 94.49% incidence of forecasting established a relationship between the plant and the soil of Igbaletere dump site. Key words : Refuse, dumpsite, heavy metals, plants.

Subsurface Contamination In The Vadose Zone By Leachate At Four Open Refuse Dumps In Maiduguri, North East Nigeria

The paper investigates the behaviour of four parameters namely chloride, sodium, potassium and nitrate underneath open dumps in an arid environment. Four sites were chosen for the study. These are University of Maiduguri (Unimaid), Lamisula, Wulari and the Kasuwa Shanu (Cattle Market) refuse dump sites. The first three are domestic solid waste dumps while the latter is an animal market waste dump. Soil samples were collected from these four dump sites. From each site was taken background sample at depths of 0.01m. All the parameters were detectable at all sites understudied at this depth. Chloride showed the clearest and most consistent behaviour at the four sites for the parameters tested. The consistency of chloride qualified it to be used a base for consideration to establish any other consistent parameter. Chloride and/or sodium can be used as conservative tracers in the vadose zone of the arid region to monitor the movement of leachate to protect the ground water system. The natural soil studied exhibited attenuation properties.

Fractionation of Lead and Cadmium in Refuse Dump Soil Treated With Cassava Mill Effluent

The effect of application of cassava (Manihot esculenta) processing mill effluent (CME) on the chemical fractionation of lead (Pb) and cadmium (Cd) in soil obtained from a refuse dump site was assessed in this study. Selected physiochemical properties of the soil and CME were determined while four different amounts of the CME were applied to the soil. The refuse dump soil had average pH of 6.2, while the cation exchange capacity was dominated by calcium. Similarly, the CME had a mean pH of 4.21 and high mean phosphorus concentration of 3160mg/kg. Chemical fractionation of the soil not containing CME showed 58.65 and 7.90mg/kg of Pb and Cd respectively in the carbonate fraction. Following the application of CME, there was redistribution of Pb and Cd in the different fractions. CME contributed to increase Cd amount in the carbonate fraction, while the residual fraction had almost uniform distribution of Cd with the various treatments of CME. However, the result indicated that depending on the applied amount of the CME there was an overall reduction in the concentration of Pb in the different fraction, while there were corresponding increases for Cd amongst the various fractions in the soil.Key words: Chemical fractionation, lead, cadmium, dump soil, cassava mill-effluent, cation exchange.The Journal of Agriculture and Environment Vol:9, Jun.2008 Page: 10-15

Potential groundwater contamination with toxic metals around refuse dumps in some parts of Lagos metropolis, Nigeria

Industrial evolution in developing countries, most especially Nigeria in the last century, has resulted in geometrical increase in waste generation compared to the arithmetic progress in management methods, thereby creating the problem of effective waste management and disposal. Wastes generated from industries have become a major source of pollution of groundwater when contaminants become leached into the groundwater. Water samples collected from 44 wells within 25 m radius from six refuse dump sites within Lagos metropolis during the months of February and September, 2006 were analyzed for nine heavy metals, namely, Lead (Pb), Chromium (Cr), Zinc (Zn), Cadmium (Cd), Nickel (Ni), Cobalt (Co), Iron (Fe), Manganese (Mn) and Copper (Cu), using AAS according to standard procedures. The results showed elevated concentrations of most heavy metals determined. Pb, Cd, Mn and Fe have their concentrations clearly above the World Health Organization (WHO) and Standard Organization of Nigeria (SON) recommended limit for potable water, showing contamination from the refuse dumps, while the concentrations of Cu and Zn were below toxic levels for drinking water in all the samples. Co was not detected in most of the samples, while the concentration of Ni detected was also quite low except at one of the sites where it was above the recommended level.

Evaluation of physicochemical properties and distribution of Pb, Cd, Cr and Ni in soils and growing plants around refuse dumpsites in Akure, Nigeria.

The physicochemical properties and distribution of Pb, Cd, Cr and Ni in soils and growing plants around refuse dumpsites in Akure, Southwestern Nigeria were evaluated to ascertain the impact of the wastes on these soil quality indices and edible plants. The soils close to the dumpsites were more acidic (pH, 5.50) compared with the soils away (25.0 m) from the sites. Also there were corresponding increases in the organic carbon and cation exchange capacities of the soil indicating measurable levels of biodegradability of the wastes. Pb, Cd, Cr and Ni have maximum concentrations of 23.00, 2.91, 9.00 and 24.00 mg/kg respectively in the soils. The amount of Cd determined in the soils was consistent with the critical level obtained for agricultural soils. Results obtained from the plant tissues analysed showed that 0.84 mg/kg Pb was detected in the root of Zea mays, while 0.25 mg/kg Ni was obtained in the root of Sorghum vulgare. Talinum triangulare and Amaranthus crucantus did not possess detectable levels of these metals. The present study has justified the need to continually assess the quality of soils, and the concentration of certain heavy/toxic metals in growing plants around refuse dumpsites.

Radiation Dose Survey of Refuse Dumpsites in Abeokuta in Ogun State in the Southwestern Zone of Nigeria

Radiation Dose Survey of Refuse Dumpsites in Abeokuta in Ogun State in the Southwestern Zone of Nigeria

Determination of the Level of Contamination of Underground Water (hand- dug well) by Organic Waste: A case Study of Ado-Ekiti, Nigeria.

The recent increase in urbanization has lead to increase in city population, spatial size, and generation of waste. This is a common phenomenon in Nigeria Cities, where Ado-Ekiti is a typical example. With the ever increasing population coupled with increasing waste (contaminant) generation and high demand for potable water, there have been reported cases of water associated health problems in the state specialist hospital. The aim of this study is to determine the level of contamination of hand-dug well which is one of the major source of water supply for the population. Water samples were taken from a total of fifteen wells at the vicinity of three major refuse dumpsite taking measurement of depth of the well, diameter, volume of water, distance to toilet and dumpsite and the physical condition of the wells. The determination of bacteria level was done using, Experimental scientific set standard. The total coliform bacteria count shows that the water is exposed to serious and complex contaminations, which indicates source pollutant of sewage and faecal materials from man and animal. With the findings, location, design and construction of wells should not be determined by only hydro geological facts, but a set standard that will put distance from toilet/dumpsite into consideration should be strictly followed. Also health workers should carry out regular monitoring of the well for contaminations. Ethiopian Journal of Education and Sciences Vol. 3 (1) 2007: pp. 43-50

Seasonal variations in heavy metal concentrations in soil and some selected crops at a landfill in Nigeria

In this study, the seasonal variations in concentrations of the heavy metals - As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn - in soil and crops from a farm near the refuse dump site of Obafemi Awolowo University, Ile-Ife, Nigeria were investigated during the two major seasons of Nigeria. This was done to assess the pollution status of the farm and hence the safety levels of the crops produced. Soil and crop samples collected during the 2005/2006 rainy and dry seasons were treated and digested using standard wet digestion methods. Heavy metals were determined with Atomic Absorption Spectrophotometer (AAS). Analytical results of soil from landfill indicated that in the wet and dry seasons, values for Cd, Cu, Fe, Ni, Cr, Zn, Co and Pb were higher than normal levels of a typical agricultural soil, but As (3.20 and 4.13 mg/kg) was found to be within the acceptable range while Mn values of 597.00 - 828.37 mgkg-1 were slightly above the usual background levels. The study showed highest concentrations of As (8.31 mg/kg), Cr (9.00 mg/kg) and Ni (40.00 mg/kg) inManihot esculenta leaves; Cu (25.0 0 mg/kg) and Fe (176.00 mg/kg) inXantosoma mafaffa tuber; Cd (14.50 mg/kg), Co (22.50 mg/kg), Mn (189.50 mg/kg), Pb (680.00 mg/kg) and Zn (440.59 mg/kg) in Talinum triangulare. In general, the levels of heavy metals in soil and crops were higher in the dry season than in the wet season, but this difference is not statistically significant. Particularly, the levels of As, Cd, Cr, Ni, and Pb were above the critical toxic level in plant leaves in both dry and wet seasons while Zn and Cu occurred at toxic levels only in the dry season. Key words: Contamination, heavy metals, landfill, refuse dump, transfer factor

Gamma spectroscopic assay of soil samples from waste dump sites in Port Harcourt, Nigeria

A lead shielded 7.6 cm×7.6 cm NaI (Tl) detector and a Canberra Multichannel Analyzer were employed for a gamma spectrometric assay of 100 soil samples from refuse dump sites in Port Harcourt city and environs. The massic activities of 40K, 226Ra and 228Ra were determined and found to correspond to natural levels of some 10 Bq/kg. No gamma-emitting anthropogenic radionuclides were detected. The mean radium equivalent is 44.2 Bq/kg giving a dose rate of 24.6 μSv/year.

Heavy Metal Contamination of Foods by Refuse Dump Sites in Awka, Southeastern Nigeria

The impact of heavy metals from refuse dumps on soil, food, and water qualities in Awka, Nigeria was studied. Soil samples (top and 1.35 m deep) were collected from five refuse dumps digested with conc. HNO3 and HClO4. The heavy metals (lead, manganese, arsenic, chromium, cadmium, and nickel) in vegetables (spinach, fluted pumpkin), root crop (cocoyam), and surface and ground water were determined using an atomic absorption spectrophotometer (AAS). Chemical properties of the soil and bacteria were determined. Heavy metals were found to be more concentrated at a depth of 1.35 m. Manganese was high in shallow wells and borehole water samples with the highest levels as 0.538 and 0.325 mg/l, respectively. Nickel levels in the borehole sample ranged from 0.001 to 0.227 mg/l, whereas the highest level of lead was 0.01 mg/l. The Obibia stream had the highest levels of manganese and lead. Linear regression analyses showed that the relationship between soil heavy metals and farm produce heavy metals was strong. Taken together, we may conclude that the consumption of leafy vegetables and crops produced on contaminated soils may pose a health risk to those that reside around the refuse dumps.

Concentration and chemical speciation for the determination of Cu, Zn, Ni, Pb and Cd from refuse dump soils using the optimized BCR sequential extraction procedure

The optimized BCR sequential extraction procedure (proposed by the Standards, Measurements and Testing Programme (SM&T) of the European Union) was applied to seven topsoil samples from refuse dump sites for the determination of Cu, Zn, Ni, Pb and Cd. The metals were partitioned into four operationally defined chemical fractions: acid extractable, reducible, oxidizable and residual, and analysed using flame atomic absorption spectrophotometry, FAAS.