International Journal of Emerging Research in Engineering, Science, and Management
Vol. 5, Issue 3, pp. 129-144, Jul-Sep 2026.
https://doi.org/10.58482/ijeresm.v5i3.9

Received: 10 Mar 2026 | Revised: 13 Jul 2026 | Accepted: 29 Jul 2026 | Published: 24 Sep 2026

Hydraulic Performance Evaluation of Clay, Laterite, and Bentonite-Modified Laterite Soils for Use as Liner Materials

1Daniel Ackah Brobbey

2Charles Kahanji

3Mususu Kosta Mpongo Kaonda

1,2Department of Civil and Environmental Engineering, The University of Zambia, Lusaka, Zambia.
1Department of Civil Engineering, Cape Coast Technical University, Cape Coast, Ghana.
3Department of Metallurgical Engineering, The University of Zambia, Lusaka, Zambia.

Abstract: Artisanal and small-scale gold mining (ASGM) generates large volumes of tailings that pose serious risks to soil and groundwater due to inadequate containment systems. Developing cost-effective, locally available liner materials is therefore critical to improving environmental protection in resource-constrained settings. This study evaluates the hydraulic conductivity of clays, laterite soils, and bentonite-modified laterites as potential liner materials for tailings storage facilities. Three clay soils (CL1–CL3), three lateritic soils (LS1–LS3), and calcium bentonite were characterised through particle size distribution, Atterberg limits, compaction, free swell index, X-ray diffraction (XRD), chemical analysis, and hydraulic conductivity testing. Untreated clays exhibited moderate to high plasticity (LL = 41–71%; PI = 25–44%) and low hydraulic conductivity (10⁻¹⁰ – 10⁻¹¹ m/s), satisfying international liner hydraulic conductivity criteria. In contrast, untreated laterites showed low plasticity (PI = 9–17%) and higher hydraulic conductivity (10⁻⁸–10⁻⁹ m/s), making them unsuitable as standalone liners. Mineralogical analysis revealed kaolinite and vermiculite dominance in clays; laterites contained quartz, hematite, and kaolinite, while bentonite is montmorillonite-rich. Incremental bentonite contents (1–10%) increased linear shrinkage, liquid limit, plasticity index, and free swell index, while decreasing maximum dry density and increasing optimum moisture content. Hydraulic conductivity decreased by 1–2 orders of magnitude with increased bentonite addition, meeting the adopted hydraulic conductivity criterion of 1 x 10⁻⁹ m/s. Depending on the initial gradation, baseline hydraulic conductivity of the laterite soil, and the hydraulic gradients under which the samples were tested, 2–4% bentonite addition resulted in a hydraulic conductivity of <1 × 10⁻⁹ m/s. The results indicate that bentonite-modified laterite is promising for liner applications under the tested laboratory conditions.

Keywords: Bentonite-modified laterite, hydraulic conductivity, soil liners, tailings containment, artisanal and small-scale gold mining.

References
  1. G. Hilson, S. Mondlane, A. Hilson, A. Arnall, and T. Laing, “Formalizing artisanal and small-scale mining in Mozambique: Concerns, priorities and challenges,” Resources Policy, vol. 71, p. 102001, Feb. 2021. https://doi.org/10.1016/j.resourpol.2021.102001
  2. A. Benshaul-Tolonen, P. Chuhan-Pole, A. Dabalen, A. Kotsadam, and A. Sanoh, “The local socioeconomic effects of gold mining: Evidence from Ghana,” The Extractive Industries and Society, vol. 6, no. 4, pp. 1234–1255, Sep. 2019. https://doi.org/10.1016/j.exis.2019.07.008
  3. G. Hilson, “Farming, small-scale mining and rural livelihoods in Sub-Saharan Africa: A critical overview,” The Extractive Industries and Society, vol. 3, no. 2, pp. 547–563, Mar. 2016. https://doi.org/10.1016/j.exis.2016.02.003
  4. A. E. Duncan, “The dangerous couple: Illegal mining and water pollution—A case study in Fena River in the Ashanti Region of Ghana,” Journal of Chemistry, vol. 2020, Art. no. 2378560, 2020. https://doi.org/10.1155/2020/2378560
  5. B. N. A. Aryee, B. K. Ntibery, and E. Atorkui, “Trends in the small-scale mining of precious minerals in Ghana: a perspective on its environmental impact,” Journal of Cleaner Production, vol. 11, no. 2, pp. 131–140, Nov. 2002. https://doi.org/10.1016/S0959-6526(02)00043-4
  6. L. J. Esdaile and J. M. Chalker, “The mercury problem in artisanal and Small‐Scale gold mining,” Chemistry - a European Journal, vol. 24, no. 27, pp. 6905–6916, Jan. 2018. https://doi.org/10.1002/chem.201704840
  7. C. G. Amedjoe and S. K. Y. Gawu, “A survey of mining and tailings disposal practices of selected artisanal and small scale mining companies in Ghana,” Research Journal of Environmental and Earth Sciences, vol. 5, no. 12, pp. 744–750, Dec. 2013. https://doi.org/10.19026/rjees.5.5731
  8. M. Rajaee, R. Long, E. Renne, and N. Basu, “Mercury exposure assessment and spatial distribution in a Ghanaian Small-Scale gold mining community,” International Journal of Environmental Research and Public Health, vol. 12, no. 9, pp. 10755–10782, Sep. 2015. https://doi.org/10.3390/ijerph120910755
  9. H. Gibb and K. G. O’Leary, “Mercury Exposure and Health Impacts among Individuals in the Artisanal and Small-Scale Gold Mining Community: A Comprehensive Review,” Environmental Health Perspectives, vol. 122, no. 7, pp. 667–672, Mar. 2014. https://doi.org/10.1289/ehp.1307864
  10. R. K. Rowe, “Environmental geotechnics: Looking back, looking forward,” Rivista Italiana di Geotecnica, vol. 52, no. 4, pp. 8–40, 2018. https://doi.org/10.19199/2018.4.0557-1405.008
  11. D. Kossoff, W. E. Dubbin, M. Alfredsson, S. J. Edwards, M. G. Macklin, and K. A. Hudson-Edwards, “Mine tailings dams: Characteristics, failure, environmental impacts, and remediation,” Applied Geochemistry, vol. 51, pp. 229–245, Oct. 2014. https://doi.org/10.1016/j.apgeochem.2014.09.010
  12. Environment Agency, “Earthworks in landfill engineering: LFE4,” GOV.UK, Jun. 23, 2014. https://www.gov.uk/government/publications/earthworks-in-landfill-engineering-lfe4
  13. W. G. Holtz and H. J. Gibbs, “Engineering properties of expansive clays,” Transactions of the American Society of Civil Engineers, vol. 121, no. 1, pp. 641–663, Jan. 1956. https://doi.org/10.1061/taceat.0007325
  14. ASTM International, ASTM D420-18: Standard Guide for Site Characterization for Engineering Design and Construction Purposes. West Conshohocken, PA, USA: ASTM International, 2018. https://store.astm.org/d0420-18.html
  15. H. Nath, M. H. Kabir, A.-A. Kafy, Z. A. Rahaman, and M. T. Rahman, “Geotechnical properties and applicability of bentonite-modified local soil as landfill and environmental sustainability liners,” Environmental and Sustainability Indicators, vol. 18, Art. no. 100241, Feb. 2023. https://doi.org/10.1016/j.indic.2023.100241
  16. British Standards Institution, BS 1377-2:2022, Methods of Test for Soils for Civil Engineering Purposes—Classification Tests and Determination of Geotechnical Properties. London, U.K.: BSI, 2022.
  17. Bureau of Indian Standards, IS 2720 (Part 40):1977, Methods of Test for Soils—Part 40: Determination of Free Swell Index of Soils. New Delhi, India: BIS, 1977.
  18. British Standards Institution, BS 1377-4:1990, Methods of Test for Soils for Civil Engineering Purposes—Compaction-Related Tests. London, U.K.: BSI, 1990.
  19. ASTM International, ASTM D5856-15, Standard Test Method for Measurement of Hydraulic Conductivity of Porous Material Using a Rigid-Wall, Compaction-Mold Permeameter. West Conshohocken, PA, USA: ASTM International, 2015. [Withdrawn 2024].
  20. Food and Agriculture Organization of the United Nations (FAO), Standard Operating Procedure for Cation Exchange Capacity and Exchangeable Bases: 1N Ammonium Acetate, pH 7.0 Method. Rome, Italy: FAO, 2022. https://www.fao.org/3/cc1200en/cc1200en.pdf
  21. M. D. Gidigasu, Laterite Soil Engineering: Pedogenesis and Engineering Principles. Amsterdam, Netherlands: Elsevier Scientific Publishing Company, 1976.
  22. J. K. Mitchell, K. Soga, and C. O'Sullivan, Fundamentals of Soil Behavior, 4th ed. Hoboken, NJ, USA: John Wiley & Sons, 2025.
  23. F. K. Boadu, “Hydraulic Conductivity of Soils from Grain-Size Distribution: New Models,” Journal of Geotechnical and Geoenvironmental Engineering, vol. 126, no. 8, pp. 739–746, Aug. 2000. https://doi.org/10.1061/(ASCE)1090-0241(2000)126:8(739)
  24. E. Eyo, S. Abbey, J. Oti, S. Ng’ambi, E. Ganjian, and E. Coakley, “Microstructure and Physical-Mechanical characteristics of treated Kaolin-Bentonite mixture for application in compacted liner systems,” Sustainability, vol. 13, no. 4, p. 1617, Feb. 2021. https://doi.org/10.3390/su13041617
  25. Z. Zeng, Y.-J. Cui, and J. Talandier, “Evaluating the influence of soil plasticity on hydraulic conductivity based on a general capillary model,” Engineering Geology, vol. 278, Art. no. 105826, Sep. 2020. https://doi.org/10.1016/j.enggeo.2020.105826
  26. D. M. Moore and R. C. Reynolds Jr., X-Ray Diffraction and the Identification and Analysis of Clay Minerals. Oxford, U.K.: Oxford University Press, 1989.
  27. C. H. Benson and J. M. Trast, “Hydraulic conductivity of thirteen compacted clays,” Clays and Clay Minerals, vol. 43, no. 6, pp. 669–681, Dec. 1995. https://doi.org/10.1346/ccmn.1995.0430603
×

© 2026 The Author(s). Published by IJERESM. This work is licensed under the Creative Commons Attribution 4.0 International License.

Archiving: All articles are permanently archived in Zenodo IJERESM Community.