IWRA Proceedings

GROUNDWATER STATUS

• Groundwater at risk: Groundwater resources are threatened globally
• Increasing demand: Public water supply, industry, and agriculture expected to increase and,consequently, also water demand
• Pollution: Depending on the source water used for aquifer recharge (e.g. river water, urban stormwater, or treated wastewater) a large variety of contaminants may be present.
• Cost: Wastewater treatment and reclamation technologies
• Monitoring: There is an urgent need to strengthen data collection protocols to know the current real state of groundwater bodies.

RESULTS

Sand in continuous removes CECs in 37%, but under pulses does not reduce them.
Selective removal:
◦ 1H-benzotriazole, 4-Methyl-1H-benzotriazole, Dimethyl-benzotriazole, Imiodacloprid...: Increased in
sand, but decreased in both compost and woodchips (higher extent) reactive barriers.
◦ Hydroxycarbamazepine, 10,11-dihydroxycarbamazepine, Carbamazepine-10,11-epoxy, Carbamazepine ..:
Only reduced in both compost and woodchips (higher extent) reactive barriers.
◦ Lorazepam, Diclofenac, Diuron,... : only reduced in woodchips reactive barrier.
◦ Valsartan acid, Clarithromycin, PPG n10,...: only reduced in compost reactive barrier.

CONCLUSIONS

The reduction of CECs, demonstrates that the implementation of SAT holds a great potential to attenuate the toxic effects-risk associated to WWTP effluents, allowing their safer potential use in aquifer recharge schemes.

The degradation observed suggests that reactive barriers composed of a mixture of diverse materials would be effective in degrading pollutants with a wide range of physicochemical properties in one treatment.

A functional SAT system with the capacity to reduce CECs from recharge water would be perceived as a natural-based cost-effective approach to face current issues related to aquifer recharge, in connection with the circular  economy, groundwater and water reuse policies.

18 January 2023 - 11:00h CET