The performance of natural clay as a barrier to the diffusion of municipal solid waste landfill leachates

Abstract

In this paper, the diffusion of solutes in natural clay from a concentrated solution consisting primarily of ammonium, sodium and chloride ions at a pH level of 8 was studied and was based on an existing 20-year-old landfill. Contaminant transport through clay liners was predicted using transport and reaction geochemical codes to help explain the experimental data. The model predicted the chloride anion diffusion and cation exchange processes for three different experiments: (1) small-scale interactions in compacted clay, (2) 1:1 European Union (EU) Directive demonstration experiments (0.5-m-thick clay barrier), and (3) analysis of a bore hole with core recovery drilled in an old landfill located above a similar type of clay as that studied in (1) and (2). Orders of magnitude between 10(-10) and 10(-9) m(2) s(-1) were used for the apparent diffusion coefficient to fit the chloride profiles at the different scales; however, at larger space and time scales, diffusion was retarded due to the presence of more consolidated, non-mechanically disturbed clay materials at large depths in a natural clay-rock emplacement.

Twenty years of global groundwater research: A Science Citation Index Expanded-based bibliometric survey (1993–2012)

“…Because of it being an essential media of groundwater interacting with the surface environment, a large number of studies focusing on soil properties, the movement of contaminants through soil, and the mutual influence of soil and groundwater (Beldring et al, 1999;Seeboonruang, 2012;Cuevas et al, 2012). Groundwater serves as a vital source of ''drinking water'' in most countries worldwide (especially in arid and rural areas).…”

Evaluation of clay soils’ permeability: A comparative study between the natural, compacted, and consolidated clay soils

“…Removal of metals is achieved by adsorption with ilter materials [11,12]. It is generally used as clay liners barrier to obstruct leachate transport and water source contamination [11,13,14]. The bottom liner can adsorb metal ions [11].…”

A Review on Bioremediation of Heavy Metals in Contaminated Water

“…Heavy metal poisoning can result from drinking water contamination (e.g., lead pipes, industrial and consumer wastes), intake via the food chain or high ambient air concentrations near emission sources 15 . The diffusion phenomenon of contaminants through soil layers and the change in mobility of heavy metals in aquifer with intrusion of organic pollutants are being studied in more details in recent years 16 . With rapid industrialization pollution is in rapid increase.…”