Heavy metals such as arsenic, chromium, copper, lead, zink etc. are frequent and hazardous pollutants of groundwater. However, there are no sustainable and economically feasible technologies available to remove heavy metals from aquifers. Pumping groundwater and treating above ground by adsorption to iron oxides is an option which, however, is very costly and needs operation for very long time. Thus, we developed an in situ technology for heavy metal removal by adsorption barriers. In contrast to other proposed nanoparticle technologies our new iron-oxide particles are true colloids which can be injected into sediments like liquids over several meter distances where they precipitate and cover the sediment matrix. Polluted groundwater can then flow through the barrier and heavy metals adsorb to the iron oxide releasing purified water. The new technology will be tested and developed to market readiness level.

Within the reground-project we will remediate two industrial sites in Portugal and Spain. In parallel, we further develop the iron-oxide particles to improve the adsorption capacity and injection properties. Thus, we provide an economic and sustainable technology for the international remediation business.

Advantages of our new technology are the cost-effective in situ treatment of heavy metal contaminated sites by implementing adsorption barriers through:

• Using existing or newly implemented wells or direct push technology
• Application even in difficult areas (industrial sites)
• Single and quick injection of colloidal iron oxides
• Migration of the particles in the conductive zones
• Efficient removal of heavy metals
• Long lasting adsorption and operation of the barrier