Groundwater Quality Characterisation of Selected Hand-dug Wells and Geological Implications in the Assin North Municipality, Ghana

Main Article Content

G. M. Tetteh
P. Dwamena- Boateng
R. O. Donkor

Abstract

Water from ten hand-dug wells from Assin North Municipality in Ghana were analysed at Ghana Water Company Limited Quality Assurance Laboratory, Ho in Ghana for various physico-chemical parameters. The analyses used standard methods with chemicals of AR grade; pH was measured with the Horiba Compact B-122 and Inolab 7300 Conductivity/TDS portable meter. Colour, turbidity, aluminium, copper, sulphate and total iron were analysed by spectrophotometry using Hach DR/2500 following standard methods. Flame photometer was used for determination of metal ions Na+, K+ and Ca2+. Silver nitrate method was used to estimate chloride, sulphate was determined by turbidimetric method. Total hardness was calculated by complexometric titration using EDTA. The results of the analyses show pH 6.0 to 7.2 with a mean of 6.5, conductivity from 300 to 800 μS/cm, TDS range from 90 to 400 mg/l. Piper Trilinear diagram revealed three main water types - calcium bicarbonate (Ca+Mg-HCO3) possibly sourced from Ca-plagioclase, biotite and amphibole; sodium chloride (Na-Cl) from Na-plagioclase, muscovite and chlorite; and mixed water types which may be due to the combined effect of Birimian metasedimentary rocks, Belt granitoid and pegmatites that released into the water through cation exchange and accounted for Na+ in the Na-Cl water type. Chloride in a few hand-dug wells may be linked to mineralogy crystallised from marine deposited sediments and infiltration of rainwater along fractures in the rocks. Hence most of the water samples have Na/Cl ratios<0.86. The rainwater in the area with weak acidity possibly infiltrated into the soil to cause appreciable concentration of HCO3- in the studied water. The total coliform values in water were less harmful as there was no faecal coliforms, though total microbial values in hand-dug wells X4 and X10 with total coliform values of 2.2 and 5.1 MPN/100ml respectively exceed the WHO guidelines. Hand-dug wells X4 and X6 in the study probably ended in aquifers in the weathered zone with the rest of the wells in fresh fractured horizons of the granitoids. Na/Cl ratios>1 (for water samples X1, X7 and X8) might have been due to contamination from anthropogenic sources. Pearson correlation indicates strong and positive correlation of TDS<Mg< Na with conductivity. All the water samples were safe for human consumption.

Keywords:
Groundwater, physico-chemical parameters, water types;, birimian rocks, mineralogy.

Article Details

How to Cite
Tetteh, G. M., Boateng, P. D.-, & Donkor, R. O. (2020). Groundwater Quality Characterisation of Selected Hand-dug Wells and Geological Implications in the Assin North Municipality, Ghana. Journal of Geography, Environment and Earth Science International, 24(9), 13-24. https://doi.org/10.9734/jgeesi/2020/v24i930250
Section
Original Research Article

References

Yidana SM, Ophori D, Banoeng-Yakubo B. Hydrogeo logical and hydrochemical characterisation of the Voltaian Basin: theAfram Plains area. Environmental Geology. 2008a;53:1213-1223.

World Health Organisation. Guidelines for drinking water quality. Recommendations. Geneva, Switzerland. 1984;(1).

Waller RM. Groundwater Wells. Accessed: 14 November 2020. Available:https://www.usgs.gov/special-topic/water-science-school/science/groundwater-wells?qt-science_center_objects=0#qt-science_center_objects.

Anonymous. Assin North Municipal District; 2013. Accessed: 14 November 2020. Available:http://en.wikipedia.org/wiki/Assin_North_Municipal_District.

Oduro-Denkyira A, Quanning AK. Population & housing census. district analytical report Assin North Municipal. Ghana Statistical Service; 2014. Accessed: 14November 2020. Available:https://www2.statsghana.gov.gh/docfiles/2010_District_Report/Central/Assin%20North.pdf

Kesse GO. The mineral and rock resources of Ghana, AA Balkema Publishers, Rotterdam; 1985.

Meta KV. Physicochemical characteristics and statistical study of groundwater of some places of vadgam taluka in Banaskantha District of Gujarat State (India). Journal of Chemical and Pharmaceutical Research. 2010.4: 663­670.

Saleem A, Dandigi MN, Kumar KV. Correlation-regression model for physico-chemical quality of groundwater in the South Indian City of Gulbarga. African Journal of Environmental Science and Technology. 2012;6(9):353-364.

APHA. Standard methods for the examination of water and wastewater, part 3, determination of metals. 17th, American Public Health Association, Washington DC. 1989;164.

APHA. Compendium methods for the microbiological examination of foods. 16th Edition, American Public Health Association, Washington DC; 1992.

Morais IPA, Rangel AOSS, Renata M, Souto S. Determination of sulphate in natural and residual waters by turbidimetric flow-injection analysis. Journal of AOAC International, 2001;84(1):59-64. Available:https://Doi.Org/10.1093/Jaoac/84.1.59

Naily W. February. Ratio of major ions in groundwater to determine salt water intrusion in coastal areas. In: IOP Conference Series: Earth and environmental science. IOP Publishing. 2018;118(1):012-021.

Ewusi A, Appiah Otoo I, Ahenkorah I, Seidu J, Akiti TT, Osae S et al. Origin of salinity in groundwater at ekumfi akwakrom and ekumfi asokwa in the mankessim municipality of the central region of Ghana. International Journal of Water Research. 2017;7(1):8-16.

Oberg G. Chloride and organic chlorine in soil. Ada Hydrochimica et Hydrobiologica.1998;26:137-144.

Zreda MG, Phillips FM, Elmore D, Kubik PW, Sharma P, Dorn RI.Cosmogenic 36C1 production rates in terrestrial rocks. Earth and Planetary Science Letters. 1991;105: 94-109.

Ganyaglo SY, Banoeng-Yakubo B, Osae, S, Dampare SB, Fianko, JRH, Bhuiyan, MA. Hydrochemical and isotopic characterisation of groundwaters in the eastern region of Ghana; 2010. Accessed: 17 November 2020. Available:http://www.scrip.org/journal/jwarp

Faure G. Principles and Applications of Inorganic Geochemistry, Prentice Hall; 1991.

Aydin A. The microbiological and physico-chemical quality of groundwater in West Thrace, Turkey. Polish Journal of Environmental Studies. 2007;16:377-383.

Anonymous. Guidelines for drinking-water quality. Health criteria and other supporting information and addendum, 2nd ed. world health organisation, Geneva. 1996;2.

Leube A, Hirdes W, Mauer R, Kesse GO. The early proterozoic birimian supergroup of Ghana and some aspects of its associated gold Mineralisation, Precambrian Research. 1990;46:136-165.

Bello O, Osho A, Bello T. Microbial quality and antibiotic susceptibility profiles of bacterial isolates from borehole water used by some schools in Ijebu-Ode, Southwestern Nigeria. Scholars Academic Journal of Biosciences. 2013;1:4-13.

Champ DR, Schroeter J. Bacterial transport in fractured rock - A field-scale tracer test at the Chalk River Nuclear Laboratories. Water Science and Technology. 1988;20(11112): 81-87.

Anonymous. Coliform bacteria in Drinking Water. New York State Department of Health Supplies; 2004. Accessed:14 November 2020. Available:https://www.health.ny.gov/environmental/water/drinking/docs/coliform_bacteria.pdf

Anonymous. Difference between coliform and faecal coliform; 2017. Accessed:14 November 2020. Available:http://www.differencebetween.com/difference-between-coliform-and-vs-faecal-coliform/

Ewusi A, Seidu J. Hydrogeology of the granitic rocks in the sekyere south district of Ashanti Region, Ghana. Journal of Geoscience and Environment Protection. 2018;6:252-263.