In the northern part of the Netherlands, natural gas is being processed, removing traces of water vapour and contaminations. This has caused groundwater pollution that became an environmental burden due to the high levels of benzene and chlorinated hydrocarbons.

Wetlantec designed a pilot plant for the remediation of the groundwater situation, using a vertical flow constructed wetland filter. This installation has been working since 1999 and shows impressive results: benzene levels were reduced from 300 μg/l to less then 1 μg/l ! Currently the installation is processing roughly 40 m3 polluted groundwater per day.