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Core Ideas

• “Wicking” salts from brine-impacted soils may be an effective means of remediation.
• Wicking materials reduced the mass of Na in brine-impacted soil columns up to 88%.
• This method may expedite remediation of brine-impacted soils with shallow water tables.

Accidental releases of brine, derived from oil and gas development, in the Williston Basin in North America have become frequent in recent years. Oil-field brines are primarily composed of sodium chloride and exhibit electrical conductivities exceeding 200 dS m^-1 and total dissolved solids exceeding 250 g L^-1. Current in situ remediation strategies involve the incorporation of divalent-cation rich amendments to displace and then rain and irrigation to leach sodium out of the soil profile. These methods in semiarid climates, where the evaporative demand exceeds precipitation, often achieves limited results. This study assessed the effectiveness of remediating brine-contamination by “wicking” salts from the soil surface when a shallow water table is present. During a 5-wk period, two engineered paper-based humidifier wicks and two nonengineered wicks (wheat straw and hydraulic mulch) placed on the surface of brine-contaminated soils reduced the total soil Na concentrations by 65 to 88% and 5 to 80%, respectively. Our results indicate that deployment of engineered wicks or similar, more cost effective materials may be an effective in situ remediation strategy that merits further field-scale investigation.