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The leachate from municipal solid waste, during or after rainfall, through desiccation cracks may contaminate underground aquifers in arid and semiarid regions. This experimental study proposes modified clay liners to control leachate contamination from waste. The test specimens of clay liners were prepared using a mixture of locally available clay, sand, cement and polyethylene chips to reduce the shrinkage potential. Microstructural analysis was also conducted by using Energy Dispersive X-Ray and X-Ray Diffraction. Scanning Electronic Microscopy tests were conducted to find chemical composition and microstructure of unmodified and modified soil specimens. These tests confirmed the presence of montmorillonite clay minerals that have high potential for swelling and thus volumetric shrinkage. The study proposes a combination of 15% sand, 4% cement and 0.5% polyethylene chips to reduce shrinkage potential from 17% to less than 4%. However, the effect of modification on hydraulic conductivity with water and leachate was not very significant. Based on statistical analysis, fair correlations were found between mixture composition and volumetric shrinkage.