Bentonite cut-off walls: solution for landfill remedial works

Abstract

2The application of landfill containment systems such as cut-off walls could be used effectively as one of the remedial solutions limiting environmental hazards caused by such sites. The complexity and weight of problems concerning remediation works of old sanitary landfills having been considered and interdisciplinary engineering and ecological solutions are recommended. This paper discusses threats to the environment emerging from old landfills and polluted areas and presents examples of engineering solutions used for the remediation of the old, large embankment-type Radiowo landfill located in Warsaw, Poland. The principal remediation problem for the Radiowo landfill was protection systems against leachate migration and groundwater pollution. The research included bentonite vertical barrier quality tests involving both laboratory and on-site hydraulic conductivity tests.Furthermore, a quality assessment based on the groundwater flow and transport modelling and an analysis of monitoring records are presented. The output of the research is the proposal of a dual device employing monitoring and numerical modelling processes for the purpose of controlling the self-purification of soil-water environments after the implementation of containment systems on contaminated sites.

An Experimental Assessment of the Water Permeability of Concrete with a Superplasticizer and Admixtures

“…One method that can be adapted to test the permeability of concrete is the flow pump technique used in the study of low-permeability materials [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. The idea of this method invented and developed by Olsen [ 20 , 21 ] is to ensure a constant flow rate through the sample and control of the hydraulic head difference, which stabilizes when the flow becomes steady.…”

Editorial

“…These barriers often obviate the need for the unsustainable option of last resort in environmental remediation; excavation and removal, also known as 'dig and haul'. Koda and Osinski (2017) write about the use of cement, bentonite and a special additive to create lowpermeability cut-off walls to isolate an old, unlined landfill from the prevailing groundwater. Adams et al (2017) provides a case study to illustrate key processes of an in situ method for creating trench barriers (i.e., trench mixing of soil with wet or dry binders to achieve a homogeneous barrier within a variety of geometries).…”

Application of a Bentonite Slurry Modified by Polyvinyl Alcohol in the Cutoff of a Landfill

“…Vertical cutoff walls are usually used to impede the horizontal migration of the leachate [11][12][13][14]. Backfills with low permeability (e.g., soil-bentonite slurry and cement-bentonite slurry) are usually used to fill preexcavated trenches to form continuous barriers.…”