Rheological Properties of Aqueous Colloidal Silica Suspensions Related to Amendment Delivery for Subsurface Remediation

Abstract

Abstract Colloidal silica (fumed silica) suspensions tested as carriers for remedial amendment delivery in subsurface contaminant remediation and as media for underground contamination containment. Rheological behavior of the silica suspensions under subsurface environment is not well documented while this knowledge is essential for the preparation and field injection of the suspensions. This contribution is focused on rheological characteristics of colloidal silica suspensions under various environmental conditions relevant to remedial amendment delivery for subsurface remediation. Influence of silica particle concentration, water source, ionic strength, pH, aging, amendment type and concentration, and subsurface sediment on rheological behavior of silica suspensions was evaluated. This work is the first attempt to relate the rheology of aqueous silica suspension to subsurface injection and amendment emplacement. Impact of remedial amendment and subsurface sediment is reported for the first time. Additio...