Purification of PFAS-containing well drainage water

The observation of increased PFAS levels in soil and groundwater in Antwerp and the Antwerp port area has major consequences. Construction projects are delayed because the sale of soil or spring water has become more difficult.

Hoelscher Wasserbau, of which Tjaden well drainage is part, has already had to purify the well drainage water on various construction projects in the Antwerp port area before this water could be discharged to the surface water. Not an unwise choice, given the large withdrawal flows that one has to deal with.

This is also the case with the Europa Terminal project in Antwerp. The quay of the Europa Terminal is being relocated and a large amount of groundwater has to be extracted to make the enormous earthmoving possible. The earthmoving is carried out by PCTS partner Boskalis, PCTS partner Hoelscher Wasserbau is at the bar for the well drainage.

For the duration of 8 years (!), 3 million m3 of land must be moved and almost 34 million m3 of groundwater must be extracted. A maximum of 480,000 L of groundwater is extracted and purified per hour. A treatment plant with activated carbon has been installed at the location and it has been running for 6 months now. The strict Flemish discharge standards for surface water (also for problem substances such as PFBA and Gen-X) make the treatment complex and expensive. The residence time in activated carbon is longer than normal and the use of alternative adsorbents (such as resins) is currently being studied.

The first change of activated carbon has already taken place. The loaded carbon has been disposed of for processing in a highly thermal combustion plant, so far the only common technique for the destruction of PFAS compounds. 

Contactpersoon: Arcadis, Wim Plaisier (wim.plaisier@arcadis.com)