Comparison of quantitative and qualitative data during MAR

This report assesses the impact of MAR on ambient groundwater, from the hydraulic and water quality perspective. Impact zones of MAR structures were divided into a) hydraulic impact zones and b) attenuation zones. Different transport processes of compounds during e.g. pond infiltration are schematically shown and explained (see figure).

Within this report, water quality data from one MAR site in Berlin-Tegel are compared to natural and anthropogenically influenced background values in the aquifer. Common approaches to determine background values in groundwater are introduced and described. At the MAR site in Berlin-Tegel, water quality parameters were observed in the infiltration pond (source water), in observation wells between the ponds and the production wells (impacted groundwater) and beyond the recovery wells (ambient groundwater). After hydraulic characterisation of the MAR site, observed concentrations of major ions, physico-chemical parameters, inorganic trace compounds, nutrients and organic trace compounds were compared with natural and anthropogenic background values (if any) by statistical plots.

 

 

 

 

 

 

Some tasks within DEMEAU outline supplementary field test in order to gain an improved understanding of the hydraulic behaviour and to perform new analytical techniques (i.e. bioassays) for selected MAR sites. To this end, Sant Vicenç dels Horts test site has been selected because it is an existing infiltration system (settling and infiltration pond) where some additional information could be gathered to improve the knowledge of processes, and thus the operation of the MAR site.

This report summarizes the field work which was carried out on site. It decribes the usage of temperature measurements to characterise the temporal hydraulic performance of subsurface passage. The report also includes all results from sampling campaigns for a wide range of inorganic and organic substances and decribes the usage of different bioassays for MAR. The following topics are covered:

  • Bulk chemistry: characterisation of infiltration and groundwater
  • Assessment of emerging pollutants and their behaviour during MAR
  • Using temperature of groundwater as a tracer to determine arrival time of recharged water
  • Leaching test to assess the reactivity of organic layer (laboratory test)
  • Bioassays of MAR samples

In Vall d’Uixó near Castellón (Spain) a new Managed Aquifer Recharge (MAR) site based on Aquifer Storage Transfer and Recovery (ASTR) is currently under development. The framework of the work is the collaboration between the DEMEAU project, looking for demonstrating the feasibility of MAR to eliminate emerging micropollutants and the Water Recovery project, carried out in the area to promote the implementation of a new MAR site in the Mediterranean Spanish coast. DEMEAU has contributed to the Water Recovery project by doing additional sampling campaigns to assess the potential impact of the use of reclaimed water in the system. This report presents the results obtained in La Vall d’Uixó consisting mainly in the following investigations:

  • Bulk chemistry: characterisation of source- and groundwater
  • Assessment of emerging pollutants and their qualitative behaviour during MAR
  • Entry level assessment (based on Australian Guidelines)
  • Maximal risk assessment (based on Australian Guidelines)
  • Bioassays of MAR samples

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