Mutual interactions between aquifer thermal energy storage and groundwater extraction: global sensitivity insights

Aquifer Thermal Energy Storage (ATES) is increasingly deployed in groundwater protection zones, motivating a quantitative assessment of thermal impacts on public-supply wells and the influence of supply-well pumping on ATES performance. In the Campine Basin (Belgium), we simulate three settings: balanced operation, seasonal imbalance, and multi-system deployment. Using a groundwater flow and heat-transport model. Uncertainty in hydrogeological properties and operational settings is represented with Latin Hypercube sampling, and distance-based Generalized Sensitivity Analysis (DGSA) ranks parameter sensitivity for both supply-well temperature disturbance (ΔTsupply) and ATES recovery efficiency. Supply-well ΔTsupply decreases with distance but can exceed natural seasonal variability at close spacing, particularly under imbalance and dense layouts. In the near field (≤75 m), range ΔTsupply is mainly controlled by ATES throughput and seasonal imbalance under pumping-induced convection from ATES cycling superimposed on continuous supply-well abstraction. At larger distances (≥200 m), variability is governed primarily by conductivity contrasts, porosity, and dispersivity, together with regional flow and the supply-well induced hydraulic gradient. Strong background flow and short spacing reduce recovery efficiency, and multi-system cases show cumulative plume interference. For the Campine Basin and similar hydrogeological settings, the results support site-specific setback design, operational constraints, and monitoring requirements, and the same workflow can be applied to other aquifers to derive locally appropriate permitting guidance.