Abstract: The advection-dispersion-adsorption parameters of heavy metals are crucial for evaluating the service performance of barrier systems. Efficient and reliable method to test these parameters systematically is still in lack at present. In order to obtain the advection-dispersion-adsorption parameters of heavy metal ions with less experimental quantities in a shorter test time, the soil column test using Pb²⁺ as a representative heavy metal ion was carried out in soil-bentonite. Results showed that the retardation factor of Pb²⁺ decreased from 13 to 11 when the flow rate increased from 0 m/s to 1.59×10^-7 m/s, which was consistent with the law that the larger the flow rate, the smaller the retardation factor. The advection-dispersion-adsorption parameters of Pb²⁺ obtained by this method were in good agreement with the typical values reported in previous literature, which proved the validity of this method. This method reduced the number of tests, improved the efficiency of parameter acquisition by which the test results were also more reliable by means of single parameter decoupling.

Key words: heavy metal, advection-dispersion-adsorption parameters, soil column test, soil-bentonite, barrier systems, single parameter