Relevance of charge interactions for contaminant transport in heterogeneous formations: a stochastic analysis

Abstract The electrostatic properties of clay (or other charged) mineral surfaces play a significant role in the fate, transport, persistence, and remediation subsurface contaminant plumes. This study presents stochastic assessment impact relevance microscale effects on macroscopic, field-scale transport heterogeneous groundwater systems involving spatially distributed zones. We present Monte Carlo simulations two-dimensional fields, comprising distributions physical (i.e., hydraulic conductivity, porosity, tortuosity) surface charge) properties, compare scenarios with different combination extent processes. were performed multi-continua based reactive code, MMIT-Clay, considering an explicit treatment diffuse layer results reveal that microscopic mechanisms within clay’s can significantly accelerate or retard particular depending its charge, leading to considerably solute breakthroughs mass loading/release behaviors low permeability inclusions. Furthermore, we show such variations macroscale behavior, solely driven by charge interactions, are statistically over ensembles realizations. also demonstrate omission processes, which is still common practice hydrology, lead substantial over- underestimation migration.