An integrated approach for simultaneous immobilization of lead in both contaminated soil and groundwater: Laboratory test and numerical modeling.

•Integrated approach for remediation of Pb-contaminated soil and groundwater.•High removal of Pb from groundwater in pre-amended contaminated surface soil.•High retention capacity and immobilization ability of Pb in phosphate-amended soil.•Deriving the profile distribution and treatment capacity of Pb via HYDRUS simulation.