The influence of amendments on the volumetric shrinkage and integrity of compacted clay soils used in landfill liners

1996 ◽  
Vol 86 (1-4) ◽  
pp. 263-274 ◽  
Author(s):  
G. H. Omidi ◽  
T. V. Prasad ◽  
J. C. Thomas ◽  
K. W. Brown
Keyword(s):  
Clay Soils ◽  
Volumetric Shrinkage ◽  
Compacted Clay ◽  
Landfill Liners

scholarly journals Hydraulic and Swell–Shrink Characteristics of Clay and Recycled Zeolite Mixtures for Liner Construction in Sustainable Waste Landfill

2021 ◽  
Vol 13 (13) ◽  
pp. 7301
Author(s):  
Marcin K. Widomski ◽  
Anna Musz-Pomorska ◽  
Wojciech Franus
Keyword(s):  
Hydraulic Conductivity ◽  
Exchange Capacity ◽  
Saturated Hydraulic Conductivity ◽  
Clay Soils ◽  
Compacted Clay ◽  
Clay Liner ◽  
Compacted Clay Liner ◽  
Drying And Rewetting ◽  
Swelling Characteristics ◽  
Shrinkage And Swelling

This paper presents research considering hydraulic as well as swelling and shrinkage characteristics of potential recycled fine particle materials for compacted clay liner for sustainable landfills. Five locally available clay soils mixed with 10% (by mass) of NaP1 recycled zeolite were tested. The performed analysis was based on determined plasticity, cation exchange capacity, coefficient of saturated hydraulic conductivity after compaction, several shrinkage and swelling characteristics as well as, finally, saturated hydraulic conductivity after three cycles of drying and rewetting of tested specimens and the reference samples. The obtained results showed that addition of zeolite to clay soils allowed reduction in their saturated hydraulic conductivity to meet the required threshold (≤1 × 10−9 m/s) of sealing capabilities for compacted clay liner. On the other hand, an increase in plasticity, swelling, and in several cases in shrinkage, of the clay–zeolite mixture was observed. Finally, none of the tested mixtures was able to sustain its sealing capabilities after three cycles of drying and rewetting. Thus, the studied clayey soils mixed with sustainable recycled zeolite were assessed as promising materials for compacted liner construction. However, the liner should be operated carefully to avoid extensive dissication and cracking.

Elastic Properties of Compacted Clay Soils by Laser Ultrasonics

2013 ◽  
Vol 34 (8-9) ◽  
pp. 1810-1816 ◽  
Author(s):  
M. Navarrete ◽  
F. A. Godínez ◽  
M. Villagrán-Muniz
Keyword(s):  
Elastic Properties ◽  
Laser Ultrasonics ◽  
Clay Soils ◽  
Compacted Clay

scholarly journals Interactions of Per- and Polyfluoralkyl Substances (PFAS) with Landfill Liners

2020 ◽  
Vol 1 (4) ◽  
Author(s):  
Will P Gates ◽  
◽  
Alastair JN MacLeod ◽  
Andras Fehervari ◽  
Abdelmalek Bouazza ◽  
...  
Keyword(s):  
Environmental Pollutants ◽  
Water Soluble ◽  
Compacted Clay ◽  
Geosynthetic Clay Liners ◽  
Clay Liners ◽  
Landfill Liner ◽  
Landfill Liners ◽  
Polyfluoroalkyl Substances ◽  
Published Research ◽  
Persistent Environmental Pollutants

This review synthesises the available published research on interactions of per- and polyfluoroalkyl substances (PFAS) with landfill liners, with the view to inform on the expected behaviour of these persistent environmental pollutants in landfills. The review addresses the nature and significant types of PFAS compounds that are destined for landfills, as well as their by-product. It discusses the known and anticipated interactions with separate landfill liner components, namely geomembranes, geosynthetic clay liners and compacted clay liners. Various water-soluble PFAS are shown to advectively transport through geosynthetic clay liners (GCL) and showcase the limitations of relying on mineral liners alone to retain PFAS. Addition of activated carbon, while increasing saturated hydraulic conductivity, significantly increases PFAS retention by the GCL and reduced PFAS flux to manageable concentrations. An assessment of the relative risk for environmental exposure of different types of PFAS from landfills through interaction with those liner components is achieved with reference to published case studies of PFAS detection in and around landfills from Australia and around the World.

The role of organic attenuation in saturated clay barrier system

1996 ◽  
Vol 33 (8) ◽  
pp. 145-151 ◽  
Author(s):  
Irene M. C. Lo
Keyword(s):  
Hydraulic Conductivity ◽  
Concentration Gradient ◽  
Organic Contaminants ◽  
Molecular Diffusion ◽  
Pollution Prevention ◽  
Fickian Diffusion ◽  
Compacted Clay ◽  
Landfill Liner ◽  
Landfill Liners ◽  
Saturated Clay

A review of literature finds that advection, diffusion, and retardation are the main processes that govern the migration of organic contaminants through compacted clay landfill liners. However, much emphasis is placed on the hydraulic conductivity in the specification for landfill liner design. It is misunderstood that if the hydraulic conductivity of the clay is low, then the liner must provide an adequate barrier for groundwater pollution prevention. Unfortunately, even the advection is minimal, contaminants can migrate through clay by simple Fickian diffusion at a rate that can be significant. The process of diffusion is mainly dependent on the concentration gradient between the leachate and the groundwater. If a clay lining system is installed, the only way to reduce the effect of diffusion is to reduce the concentration gradient by pollutant retardation. In this paper, the relative importance of molecular diffusion and advection, and the effect of pollutant retardation on the advective and diffusive transport are discussed using a conceptual-mathematical model. Based on a review of organic contaminant attenuation by clay liners, a guideline on the development of a high organic attenuation engineered barrier as a second line of defence for containment sites is proposed.

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