The mining of natural resources always causes environmental impacts such as land use, large quantities of waste, destruction of habitat, impairment of groundwater regime, and quite possibly contamination of soil, water, or air. Soil and groundwater remediation projects often cause high costs due to their large extent and long duration. This is the reason why a number of contaminated sites are not remediated at all. Passive in situ groundwater remediation using permeable reactive barriers (PRBs) is a relatively new and innovative technology with a high potential to significantly reduce the cost of treating contaminated shallow aquifers and therefore, contribute to the preservation of groundwater resources. The use of PRBs for groundwater protection or remediation has also been studied in other fields, for example, the treatment of metals-containing mine waters. Cationic metals usually have limited mobility in soil and groundwater with high clay and organic content, high alkalinity, and low permeability.