WP leader: Dr. Marie Pettenati (BRGM)

Outcomes from WP1 and WP2 regarding the efficacy of select treatment processes to attenuate known and unknown CECs (target and non-target analysis), the formation of TPs, the inactivation of pathogens and the removal of antibiotic-resistant bacteria/genes, as well as the reduction of ecotoxicological and human health risks will be integrated within WP3. The experimental results will be used to develop treatment process models and contaminant transport models to describe the fate and transport of CECs for above-ground engineered processes and soil-based treatment processes (i.e. SAT), respectively. Based on all information gathered, an overall evaluation procedure will be developed, tested and further refined for INPR practices in close concert with WP2 activities. The assessment and mitigation strategies will be further vetted through a facilitated dialogue with stakeholders (WP4). This iterative process enables predictions regarding the efficiency of various INPR applications independent of the selected sites.

Objectives:

• Establishment of treatment process and contaminant transport models to describe removal efficacy of viable processes applied in Indirect Potable Reuse (INPR)
• Model validation and iterative improvement (addressing the fate of indicator CECs, TP formation, pathogens, antibiotic-resistant bacteria/genes and ecological & human health)
• Overall assessment of the efficacy of various control/abatement strategies leading to INPR

Task 3.1: Modeling of CEC & TP attenuation
In Task 3.1, models for chemical oxidation processes (e.g., ozone, UV/H2O2), biological processes (e.g. biofiltration) and contaminant Transport (e.g., SAT) will be established utilizing attenuation rate constants (i.e., sorption, biotransformation, TPs) and pathogen inactivation rates derived during WP2. Process models will consider flow, water chemistry and key operating conditions specific to each process.

Task 3.2. CEC transport modeling of INPR strategies
Commonly applied INPR strategies (i.e. groundwater recharge, streamflow augmentation) at the field-scale will be simulated during Task 3.2 using combined treatment process models coupled with hydrodynamic models. Effects of a variety of risk reduction/abatement strategies will be simulated and the subsequent analysis will allow for determination of the appropriate level of spatial resolution to properly describe contaminant attenuation at the system-scale. It will also provide an assessment of which ecological status could be reached regarding chemicals in European water bodies.

Task 3.3. Evaluation of treatment processes and INPR management practices
In Task 3.3, an evaluation strategy will be developed and used to assess the effectiveness of Treatment processes via a Decision Support Framework (DSF). This considers CEC removal based on individual CEC analysis (including TPs) and non-target analysis, removal of pathogens and antibiotic resistances, reduction of ecotoxicological effects as well as feasibility, costs and energy demands of INPR processes for the pilot- and full-scale plants. Combining results from pilot-scale and field-scale sites with adapted models will enable an evaluation of INPR practices as well as the estimation of costs and drawbacks of various management (treatment) strategies. Comparison of treatment processes with regard to the changes of matrix compositions will serve as a criterion for process evaluation. To protect public health, this assessment will include toxicological evaluations and the identification of threshold values. A Centralized Knowledge Platform (CKP) will be established gathering all relevant data regarding INPR to facilitate the overall evaluation via the DSF.