Abstract

The application of orthophosphate and silicachemical treatments to contaminated land in cold regionsremains understudied. The potential of mixedsilica-orthophosphate treatments for the management of metalcontaminated sites has not been examined. Investigation andcharacterization of the mineral products which form duringtreatment, to ensure their suitability and stability forremediation and contaminant migration prevention is essential.This should be achieved prior to in-situ implementation. Thispaper observes the mineral products formed by reactionbetween orthophosphate, silica and orthophosphate-silica mixtreatment(s) and lead sulfate, copper oxide and zinc oxidesystems over 114 days using X-ray diffractometry. Detectablechanges to the mineral composition of analyzed specimensoccurred in all systems. Immobilization was most effective forlead and least effective for zinc. This study demonstrates thepotential of chemical treatments for the management of metalcontaminated sites in cold regions. However, the results of thisstudy demonstrate that treatments must be designed withconsideration of factors such as environmental risk, the variousstabilities of mineral products formed, temperature and thesolubility of contaminant phases requiring treatment.