According to the EU methodology Environmental Technology Verification, a Quick scan of the MetalRem GW technology was performed. This technology is based on the principle of applying waste material from ductile iron machining to remove Ni and Zn from groundwater in situ. Here, cast iron filings and chips are injected into an aquifer where they form a so-called permeable reactive barrier oriented perpendicular to the direction of groundwater flow. Contaminated groundwater subsequently flows through the barrier, where Ni and Zn (but also other metal(loid)s) are trapped and the water leaves the barrier with significantly lower concentrations of the target metals.
The certificate and detailed information on the technology can be found at: MetalRem GW "Technologie aplikace odpadního materiálu z obrábění tvárné litiny pro odstranění niklu a zinku z podzemních vod in situ" (zenodo.org).