Soil that is contaminated with heavy metals has become a major issue worldwide.
However, proper remediation techniques such as stabilisation/solidification (S/S)
method can be employed and is capable of controlling these heavy metals.
Conventionally, the common S/S method used cement as binder on remediating the
contaminated soil particularly heavy metals. This research is to investigate the effect
of physical and leachability of contaminated soil in S/S method when Sugarcane
Bagasse Ash (SCBA) is added to remedy contaminated soil. Landfill contaminated
soil was used to test the effectiveness of those binder. Cement was added at a
proportion of 5%, 10%, 15% and 20% in sample weights without SCBA while in
another sample; the cement was replaced by SCBA at a proportion of 2.5%, 5%,
7.5% and 10%. All samples are to be allowed to harden and cured at room
temperature for 7, 14 and 28 days. The effectiveness of the treatment was assessing
by conducting physical testing such as Unconfined Compression Strength, Water
Absorption and Permeability test. In addition, leaching tests were performed to
identify the leachate behavior of heavy metals during treatment. Three leaching tests
were conducted and they were the Toxicity Characteristic Leaching Procedure
(TCLP), Synthetic Precipitation Leaching Procedure (SPLP) and Dynamic Leaching
Test (DLT). Through the physical testing, samples containing 10% OPC mixed with
10% SCBA were found to improve the compressive strength, reduced the water
absorption and water permeability measuring 1550 MPa, 17.94% and 4.41 x 10
-10
m/s respectively. In the same way, through the statistical analysis, the R-squared for
UCS with respect to mixed design is high at 98%. However, the value for both water
absorption and permeability recorded to be marginally low, compared to the value
for strength at 89% and 88% respectively. Through the TCLP and SPLP test, results
indicated that when SCBA added to OPC content in soil samples, less heavy metal
been leached out from the S/S sample. In average, the satisfying result was shown by
samples containing 10% OPC + 10% SCBA where reduction of heavy metals in final
leachate is more than 90% for As, Cd, Cr, Pb and Zn. Through the Dynamic
Leaching Test, sample containing 10% OPC +10% SCBA showed the satisfactory
leachability index (Lx) at 9.17, 9.17, 8.81, 8.17 and 6.97 for As, Cd, Cr, Pb and Zn
respectively. This indicates that the use of cement and SCBA as a binder was
successful in remediating the contaminated soils through the S/S method
