PhD in Nature-based systems against organic micropollutants

Engineered nature-based systems to protect drinking water aquifers against organic micropollutants

To mitigate seasonal water stress, drinking water companies at the high sandy soils in eastern Netherlands intend to increase aquifer recharge. However, infiltration is limited by the availability of clean surface water. Most surface waters contain pesticides and other organic micropollutants (OMP) at concentrations above 0.1 µg/L (the standard set by the European groundwater directive). To protect the groundwater quality, and to prevent the need for advanced treatment upon abstraction, there is a need for treatment prior to infiltration, preferably a nature based treatment that can be applied at water abstraction sites, which typically also have a nature and recreation function. Microorganisms in nature-based treatment systems are capable of biodegrading OMPs, however their growth and activity depends on a wide range of environmental factors. Those environmental factors can, to some extent, be controlled by the design and operation of nature-based treatment systems. In addition, nature-based systems can also be engineered to enhance the sorption of OMPs.

Research challenges

To understand how the design and operation of nature-based wetland-type systems, fed with surface water, effect the effluent quality with regard to infiltration. As part of this challenge, different wetland substrates will be evaluated including organic substrates, such as peat or wood chips. Organic materials act as absorbent and will thus increase the retention time of OMP in the system. Furthermore, organic substrates form growth substrate for certain species that might indirectly contribute to OMP biodegradation. A second element of the research challenge, is to evaluate options to control the water flow through, and oxygen supply to, the different compartments of the nature-based system.

Your assignment

You will study the processes in nature-based systems using batch, column or pot experiments under well-controlled conditions in the laboratory. You will use a broad range of analytical techniques to assess OMP degradation, organic matter fractionation, the bacterial (and possibly fungal) community development, and the role of adsorption, extracellular enzymes, Fenton (like) reactions, and reactive oxygen species.

The companies in the Groundwater technology theme aim to construct and study a 100m2 nature-based system at a drinking water abstraction site in the Netherlands. This study will be done in parallel to the PhD research, however, you will cooperate with the people doing the field work.

Your Profile

We are looking for a motivated PhD candidate with a MSc degree in Environmental Technology, Applied Biology, Soil Chemistry, or similar. You should have an affinity for collaboration with partners from the drinking water sector. Preference is given to candidates with knowledge of biological laboratory experiments, chemical oxidation, and sorption phenomena, organic matter characterization, OMP analysis by LC-MS and biomolecular tools.

Keywords: Organic micropollutants, biodegradation, nature-based, groundwater quality

Supervisory Team: University promotor and co-promotor: Assoc. Prof. Dr. Nora B. Sutton (Wageningen University, Environmental Technology), Dr. Thomas V. Wagner (Wageningen University, Environmental Technology)

Wetsus supervisor:  Dr. Roel J.W. Meulepas (Coordinator of the Groundwater technology theme)

Project partners: Groundwater Technology 

Only applications that are complete, in English, and submitted via the application webpage before the deadline will be considered eligible.

Guidelines for applicants:  https://phdpositionswetsus.eu/guide-for-applicants/