Refuse dumpsite and its associated pollutants: Spatial variations of the impact of leachates on groundwater quality

• Published in: Management of environmental quality 2018-01, Vol.29 (3), p.572-591
• Main Authors: Ojo-Awo, Nicholas Adesina, Agbabiaka, Hafeez Idowu, Ilesanmi, Abiola O.
• Format: Article
• Language: English
• Subjects: Alkalinity; Atomic absorption analysis; Biochemical oxygen demand; Cadmium; Calcium; Calcium ions; Chemical oxygen demand; Chemical properties; Contamination; Copper; Dissolved oxygen; Dissolved solids; Drinking water; Dry season; Dump leaching; Electrical conductivity; Electrical resistivity; Emission measurements; Environmental impact; Environmental quality; Groundwater; Heavy metals; Hydrology; Intestine; Iron; Irritation; Landfill; Leachates; Local government; Mercury; Municipal solid waste; Organic chemicals; Organic matter; Oxygen; Palatability; Particle size; pH effects; Photometry; Pollutants; Pollution; Precipitation; Preservation; Rain; Rainfall; Sampling; Seasons; Sodium; Solid wastes; Spectral analysis; Spectrophotometry; Statistical analysis; Surface water; Transits; Variance analysis; Waste disposal; Waste management; Waste management industry; Wastewater treatment; Water pollution; Water quality; Water resources; Water sampling; Water temperature
• ISSN: 1477-7835; 1758-6119
• DOI: 10.1108/MEQ-08-2017-0077

Purpose The purpose of this paper is to investigate the physico-chemical properties of the groundwater surrounding the Solous (solid waste dumpsite) at Isheri, Lagos, Nigeria. Design/methodology/approach In total, 40 groundwater samples were collected from ten pre-determined sampling stations. Three sample stations were established before the dumpsite; three sample stations were located in the vicinity of the dumpsite in the direction of the leachate plume, while the remaining four sample stations were situated further away and acted as a control. Sampling was carried out four times during the study period (twice each in the rainy and dry seasons). The parameters measured in situ were air and water temperatures (using mercury-in-glass bulb thermometer) and pH (using pH meter). Calcium and magnesium contents were measured using the Ca-Mg indicator; sodium content was measured using the flame emission spectrophotometry and phosphate was measured using the flame photometry. The selected heavy metals (copper, iron, lead, cadmium, zinc and manganese) were measured by using the atomic absorption spectrometer. The oxygen parameters, such as dissolved oxygen, biological oxygen demand, chemical oxygen demand and organic matter, were determined titrimetrically. The data obtained were subjected to descriptive statistics and analysis of variance (ANOVA). Findings The results showed that many parameters had higher values in the dry season than in the rainy season. Temperature (27.75±0.95°C), alkalinity (211.37±82.78 mg/LCaCO3 ), phosphate (0.30±0.07 mg/L) and sulfate (2.78±0.35 mg/L), sodium ion (41.95±18.86 mg/L), dissolved oxygen (2.98±0.57 mg/L) and COD (33.54±4.50 mg/L) had higher mean values in the dry season than in the rainy season. On the other hand, the mean values of electrical conductivity (1,224.85±370.63), nitrate (0.01±0.003 mg/L), chloride (98.76±21.58 mg/L), calcium ion (5.38±0.68 mg/L), magnesium ion (3.05±0.05 mg/L), BOD (22.37±2.20 mg/L) and pH (6.31±0.18) were higher in the rainy season than in the dry season. The heavy metals (iron 1.10±0.05 mg/L, lead 0.12±0.07 mg/L, manganese 0.01±0.004 mg/L, copper 0.15±0.003 mg/L, zinc 0.07±0.004 mg/L and cadmium 0.02±0.02 mg/L) were fairly uniform all year round. There was also a marked decline in the values as one moved away from the dumpsite. Practical implications The implication of the findings is that human health is remarkably dependent upon safe and clean drinking water. Preserving the water resources a