Geosciences and Geophysics

Biography

Biography: Bello Mojeed Adetunji

Abstract

This study characterized the general features of rainwater in the study area. Determined the spatial variation in the physio-chemical properties of rain water and investigated the influence of industrial activities around Ewekoro Cement Industry, Ogun State, Nigeria. This is with the aim to assess the impact of pollution on rain water composition. It also provides information on the air quality (total suspended particles and carbon-monoxide) and vulnerability of ecosystem to pollution in the study area. The study evaluate the chemical composition of composite samples and compare it with standards.

Rainfall was collected using bulk precipitation collector that was made up of 2 mm plastic funnel in a 5litre polythene plastic bottle which was held firmly by an iron rod that prevented it from falling. The funnel was covered with a permeable synthetic mesh that prevented the samples from being contaminated with leaves and bird dungs. The water samples were collected using standard with 2.5 ml of nitric acid (HNO3) and 2.5 ml of perchlorate acid (HCI04) solution. The data collected were subjected to descriptive statistic and the spatial variability was describe with isopleth. The secondary data involve an administrative map of the study area collected from Ogun state ministry of land and housing.

The pH of rain water around Ewekoro Industrial Area ranged 7.20 and 9.00 with a mean±SD of 9.60±0.45, pH was noticeable to have uniform concentration in all sampling locations throughout the period of the study. The range of temperature (25.42-26.82 ⁰C) with a mean±S.D of 26.34±0.72; conductivity (5.72-7.91µScm-¹) with a mean of 6.90±0.96; Acidity (2.00-15.00 mgCaCO₃ /L) with a mean±S.E of 5.33±0.46; Total hardness (0.04-1.23 mgCaCO₃ /L) with a mean±S.E of 0.65±0.04 in rain water of the study area were all fall within the WHO (2010) and Nigeria Industrial Standards (NIS, 2007) permissible limits for drinking water quality. The mean concentration for the major ions of rain water in the study area occurred within the following categories: Mg²⁺ (Ë‚0.1mg/l);N03˃Na+˃S0₄²⁺˃K⁺˃Ca²⁺ (0.1-1mg/L); The concentration of cations are higher at northern direction (point D) while the concentration of sulphate is higher at the production plant (50 m radius) of the cement industry. The mean concentration of heavy metals in the study area are as follow; Cd (0.010±0.002 mg/L), Pb (0.00±0.001mg/L), Mn (0.001±0.00mg/L). They are all fall within the WHO (2010) and the Nigeria Industrial Standard (NIS, 2007) permissible limits for drinking water quality. The study concluded that industrial activities in the study area have an influence on all the physicochemical compositions of rain water in the study area but more significant on major cation of Calcium, Magnesium, potassium and anion of sulphate, nitrate and chloride.