An improved zero-tension lysimeter to monitor colloid transport in soils

• Published in: Journal of environmental quality Vol. 23; no. 2; pp. 378 - 383
• Main Authors: Thompson, M.L, Scharf, R.L
• Format: Journal Article
• Language: English
• Published: Madison, WI American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America 01.03.1994; Crop Science Society of America; American Society of Agronomy
• Subjects: Applied sciences; CHIMIE DU SOL; COLLOIDE; COLOIDES; CONTAMINANTES; CONTROLE CONTINU; Decontamination. Miscellaneous; Exact sciences and technology; LISIMETROS; LYSIMETRE; MOUVEMENT; MOVIMIENTO; POLLUANT; Pollution; PROCESOS DE TRANSPORTE EN EL SUELO; QUIMICA DEL SUELO; Soil and sediments pollution; TRANSPORT DANS LE SOL; VIGILANCIA; Control instrumentation; Soil pollution; Transport; Pollutant behavior; Colloid; Lysimeter
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq1994.00472425002300020025x

Mobile colloids may facilitate the long transport of actinides, organic contaminants, and heavy metals in soil, surface water, and groundwater. Detection of colloid-facilitated contaminant transport in sods requires adequate monitoring before, during and after in-situ remediation treatments. Zero-tension lysimeters (ZTLs) are devices designed collect water that moves through the sod under the influence of gravity; they can also be used to collect mobile colloids. A ZTL that is suitable for monitoring colloid-facilitated contaminant migration consists of a specially designed collection cup placed below an undisturbed core of soil that has been initially withdrawn with a hydraulically powered tube. Field tests of the lysimeter were conducted at a site near Ames, IA, where three levels of municipal sewage sludge were applied to the soil in 1992. Each ZTL required about 45 min for a two-person crew to install at 50-cm depth. Turbidity measurements of leachate following summer storms revealed considerable spatial variability colloid migration supporting the use of ZTLs that can be installed quickly and cheaply in large number at a study site. The ZTL described has significantly advantages over conventional designs with respect to simplicity and speed of installation. Therefore, it allows colloid transport to be monitored at more locations at a given site. In addition, because of the improved spatial resolution in sampling and monitoring if contaminants are mobilized, their source can be more easily identified than with piezometer-based monitoring methods