Treatment of arsenic, heavy metals, and acidity using a mixed ZVI-compost PRB.

A 30-month performance evaluation of a pilot permeable reactive barrier (PRB) consisting of a mixture of leaf compost, zerovalent iron (ZVI), limestone, and pea gravel was conducted at a former phosphate fertilizer manufacturing facility in Charleston, SC. The PRB is designed to remove heavy metals and arsenic from groundwater by promoting microbially mediated sulfate reduction and sulfide-mineral precipitation and arsenic and heavy metal sorption. Performance monitoring showed effective treatment of As, Pb, Cd, Zn, and Ni from concentrations as high as 206 mg L(-1), 2.

Field column study using zerovalent iron for mercury removal from contaminated groundwater.

Passive in situ remediation technologies, for example, permeable reactive barriers, PRBs, are an attractive and less expensive alternative compared to conventional pump and treat systems for groundwater remediation. Field column experiments were conducted to evaluate the removal of dissolved mercury from groundwater using zerovalent iron as the reactive media. Two column tests were conducted over a 6-week period, which simulated 2 and 10 years of groundwater flow through a potential full-scale treatment system.