Abstract
The efficiencies of different particle sizes (< 63, 63-93, 93-106 and 106-125 um) of mined phosphate rock (PR), as well as other phosphate sources (processed and biogenic) as a chemical stabilization remediation technology and stability (in terms of heavy metals) were assessed in contaminated urban soils. The results demonstrate that the application of PR substrate with smaller particle size (< 63 urn) was sipificantly more effective than larger particle size for Cu, Co, Cd and Ph immobilization. Depending on phosphate solubility, the decrease in of metal availability was highest in biogenic ground fish hones) (0.02; 0.0; 0.005 and 0.017 mg kg(-1) for Ph, Cd, Co and Cu, respectively) and processed phosphates (0.05; 0.02; 0.22 and 2.01 mg kg(-1) for Pb, Cd, Co and Cu, respectively) than mined phosphate rock (0.03; 0.011; 1.11 and 0.005 mg kg(-1) for Pb, Cd, Co and Cu, respectively). It is noted that lower dissolution of phosphate rock may he advantageous for long term maintenance.