Guillaume Stoltz

• Ph.D.
• Engineer at French National Institute for Agriculture, Food, and Environment (INRAE)

In France, sediments from river dredging are considered as waste. Without any special treatment, they must be stored in landfills. The dredged sediments of our area of study (North of France) are polluted with trace metals (antimony and zinc are above the French regulation threshold). The main objective of this study is to develop a new method of a...

The objective of the paper is to give an update in key topics related to performance issues of barrier systems for landfills. The objective of using barrier systems is to minimize the impact of contaminants on the surrounding environment. To achieve this goal puncture protection of the geomembrane must be ensured. An update is first given with resp...

This paper explores the use of geotextiles as insulation material for energy geostructures made of compacted soil. This work is based on measurements of the thermal conductivity of four nonwoven needle-punched geotextiles of varying thicknesses made from virgin or recycled fibres. These values were measured using the hot-plate method. Then, to asse...

This paper presents an experimental and numerical investigation of the electrokinetic propagation of acid or base fronts through clayey soil. The experimental study included measuring the electric current, the mass of water extracted, and the advance of the acid and base fronts in synthetic sediment composed of 25% kaolinite and 75% silt. The resul...

This study investigates how the shear rate can affect the geomembrane - protective geotextile friction angle. Four types of geomembranes (GMB) were considered (EPDM, HPDE, PP, and PVC) and a single nonwoven needle-punched geotextile (GTXnw) was used to make the interfaces with the geomembrane. Three shear devices were used: a large-scale inclined p...

This paper presents the results of an experimental study of various geotextiles used to filter clayey sludge. The use of geotextiles to filter clayey sludge or suspensions of fine particles in water is more complex than that for filtering suspensions of granular soils. In practice, such applications generally use flocculants to postpone the formati...

The objective of the paper is to give an update in key topics related to performance issues of barrier systems for landfills. The objective of using barrier systems is to minimize the impact of contaminants on the surrounding environment. To achieve this goal puncture protection of the geomembrane must be ensured. An update is first given is this m...

Domestic waste (MSW) can be considered as a gradually changing porous medium. This paper reports tests of a new type on a waste sample in order to get correlations between mechanical and hydraulic properties. Compression tests coupled with gas permeability tests have been made on waste sample taken from a hole drilled in a French landfill. The appa...

Municipal solid waste (MSW) in landfill bioreactors is subjected to mechanical, biological, and hydrological processes. To understand these processes, four large-scale bioreactor pilots were specifically designed to simulate the behavior of waste in the core of a landfill. Here, the results of two long-term tests that were performed in two compress...

The objective of the paper is to give an update in key topics related to performance issues of barrier systems for landfills. The objective of using barrier systems is to minimize the impact of contaminants on the surrounding environment. To achieve this goal puncture protection of the geomembrane must be ensured. An update is first given is this m...

This report presents a new large-scale test apparatus (LSTA) developed to assess the efficiency of a geosynthetic reinforcement for the limitation of deformations of a geosynthetic lining system (GLS) over a 0.5 m wide cavity. Two experiments were conducted. The first one involved a geosynthetic clay liner, a nonwoven needle-punched geotextile and...

Numerical modelling approaches can aid in designing geotechnical constructions involving geosynthetics. However, the reliability of numerical results depends on how the model is developed, the constitutive model, and the set of parameters used. By comparing the numerical results with experiment, the present work verifies a numerical modelling techn...

Numerical modelling approaches can aid in designing geotechnical constructions involving geosynthetics. However, the reliability of numerical results depends on how the model is developed, the constitutive model, and the set of parameters used. By comparing the numerical results with experiment, the present work verifies a numerical modelling techn...

Geosynthetics have been extensively used in landfills as a lining system to prevent leachate infiltration into groundwater. In piggy-back landfill expansion (PBLE), consisting of building a new landfill over an existing one, a lining system is implemented between the old and new waste. In this context, interface failure (stability) and deformation...

Geosynthetics (GSY) have been used extensively in geotechnical structures in addition and as an alternative to natural materials over the last five decades. In landfills, GSY are implemented on the bottom and side slopes of the waste cells to prevent the leachate infiltration into groundwater, as a lining system. In piggy-back landfill expansions (...

During the last decades, considerable efforts have been devoted to the reduction of ultimate municipal solid waste (MSW), but landfills are still a major step in the MSW treatment process since a great part of MSW are not recyclable with the current techniques. However, it is becoming fairly difficult to find new sites to build new landfills becaus...

This paper, which is based on an Invited Lecture for the 7th International Conference on Environmental Geotechnics, gives an updated overview of the properties of transfer of geosynthetic liner materials used in environmental applications. To begin, the water-retention curves of geosynthetic clay liners (GCLs) are discussed, with the focus being on...

The mining industry produces huge amounts of waste under the form of mineral sludge, like mature fine tailings issues from the production of bituminous sands. These residues are hard to dry, in relation with their large clay content. This paper gives the result of a study of filtration under pressure of a sludge containing silt and clay by nonwoven...

Geosynthetics are manufactured products in the form of a sheet that can be constituted by several specific layers binded to each other by various means (bonding, seam, etc.). When they are integrated on a slope, the links between the different layers are subjected to shearing stresses, which suppose sufficient resistance to ensure the overall stabi...

Geosynthetic clay liners (GCLs) are placed at the bottom of waste disposal facilities where they hydrate from the subsoil and eventually from a hydraulic head on geomembranes (GMs) defects. Predicting hydration behavior of GCLs requires knowledge of the water-retention properties of the GCL along wetting paths. Given that GCLs could be subjected to...

The oil sands industry usually leads to the production of large quantities of mineral waste, such as fluid fine tailings (FFT), whose disposal is often challenging. Electrokinetic geocomposites (eGCPs) installed into the FFT disposal area may improve in situ dewatering, as eGCPs can drain water expulsed during FFT consolidation as well as impose a...

A host of mining practices produce fine-grained mineral sludge, such as mature fine tailing from oil-sand extraction. These sludges are hard to dewater because of their high clay content and their low hydraulic conductivity. This paper describes pressure filtration tests in which eight different nonwoven geotextiles (GTXs) were used to filter high-...

The positive effects of lime treatment are likely to be altered by weathering, and the sustainability of lime-treatment positive effects is in question. In this study, the effects of successive drying/wetting cycles on the hydromechanical properties of a lime-treated clayey soil are assessed. Osmotic suction-controlled oedometers were used to deter...

Standard EN ISO 12957-2 involving an inclined plane device can be used to measure the interface friction angle between two layers of geosynthetics at low normal stresses. The principle of this standard increases shear stress until the interface slides. The main objective of this study was to compare this loading method with that of the shear box wh...

This study is based on previous results of Garcin et al. (2011) and Auray et al. (2012) which presented some sand/geogrid interface friction angles obtained following two testing methods: tests using a direct shear box following the standard EN ISO 12957-1 (AFNOR, 2005) and in-situ tests. In the present work, the same soil/geogrid interfaces were t...

Municipal solid waste (MSW) in landfill bioreactors is subjected to mechanical, biological, and hydrological processes. To understand these processes, four large-scale bioreactor pilots were specifically designed to simulate the behavior of waste in the core of a landfill. Here, the results of two long-term tests that were performed in two compress...

Geotextiles are used in the constitution of landfill lining systems in order to protect the geomembrane against puncturing effects during installation of the granular drainage layer, then during the life of the landfill site, in relation with the weight of waste. The objective of this paper is to evaluate the performance of nonwoven needlepunched g...

This study concerns the feedback of a synthetic rubber geomembrane EPDM that was installed 12 years ago for the landfill cell cover of Lann Hir. An inspection visit has been organized to assess the condition of the geomembrane and sealing details. Part of the covering soil has been removed to allow visual inspection and take samples of the geomembr...

L'invention concerne un procédé de détermination d'une force de frottement à l'interface entre deux surfaces en contact l'une avec l'autre. Le procédé fait intervenir un organe élastique initialement prédéformé pour retenir un élément mobile qui repose sur un support inclinable et qui permet d'exercer une charge sur les deux surfaces en contact dis...

The main purpose of this study is to examine both at micro-and macro scales the effects of wetting / drying on swelling / shrinkage behaviour of a com-pacted expansive clayey soil treated with lime. The results showed that lime treatment was efficient to prevent the swelling, but the shrinkage remained un-changed, regardless of the added lime conte...

The main purpose of this paper is to examine the impact of a wetting and drying path on the swelling/shrinkage of a compacted lime-treated expansive clayey soil both at the macro- and micro-scales. At the macro-scale, the soil water characteristic curves (SWRCs) of the compacted lime-treated materials (0%, 2% and 5% of lime content) were determined...

Original laboratory setups are used to study the moisture retention properties of municipal solid waste taking into account the porous medium's structural evolution from compression. A controlled suction oedometer allowed the moisture retention curves (MRCs) of compacted samples to be determined for both wetting and drainage with a matric suction r...

The optimisation of landfill operation is a key challenge for the upcoming years. A promising solution to improve municipal solid waste (MSW) management is the bioreactor technology. A meso-scale (around 1m(3)) experimental set-up was performed to study the effect of moisture control in low density conditions with different leachate injection opera...

In this paper, an original large-scale experimental setup is presented to perform a complete hydro-bio-mechanical study of MSW and its biodegradation. This setup, still in an experimental phase, is intended to validate a specific metrology used to monitor long-term MSW characterization tests, and enable to identify the correlation between the bio-m...

A novel set of experimental apparatus was designed and constructed to study the changes in the fluid-flow properties of municipal solid waste (MSW) related to the physical evolution of its structure under compression. The vertical liquid and gas permeabilities of MSW samples were measured in a laboratory-constructed cell termed an oedopermeameter....

Following the basics of soil mechanics, the physico-mechanical behaviour of municipal solid waste (MSW) can be defined through constitutive relationships which are expressed with respect to three physical parameters: the dry density, the porosity and the gravimetric liquid content. In order to take into account the complexity of MSW (grain size dis...

Landfilled Municipal Solid Waste (MSW) is subject to mechanical, biological and hydrological processes. An experimental setup was developed to assess the impact of these processes under controlled conditions in large-scale compression cells that simulate site-like disposal conditions. This paper presents the results of two long-term tests performed...

An important excavation campaign of six drill holes was performed on a French landfill. The excavated waste was landfilled from 2001 to 2005 and the drilling operation reached up to 40 meters of depth. The landfill is operated by Veolia Environmental Services. Actually, this drilling campaign was carried out keeping in view the following two object...

This thesis, supported by The French Environmental Agency and VEOLIA, is related to the study of the hydro-mechanical behaviour of waste, stored in a landfill. The settlement of the different layers of a landfill, due to the compression stress, induced by the upper column of waste, conducts a decrease of the intrinsic permeability of the medium. Th...

Cette thèse, cofinancée par l'ADEME et VEOLIA, porte sur l'étude du comportement hydro-mécanique d'un déchet biodégradable déposé en Installation de Stockage de Déchets Non Dangereux (ISDND). La biodégradation induit des biogaz et le concept de bioréacteur suppose une circulation de lixiviat, d'où l'importance de l'étude des transferts des effluent...

Domestic waste (MSW) can be considered as a gradually changing porous medium. This paper reports tests of a new type on a waste sample in order to get correlations between mechanical and hydraulic properties. Compression tests coupled with gas permeability tests have been made on waste sample taken from a hole drilled in a French landfill. The appa...

Calibration of Time-Domain Reflectometry Probes to Measure Moisture Content in Municipal Solid Waste in Laboratory-Scale Cells

Les déchets biodégradables (OM) sont considérés ici comme un milieu poreux évolutif. Ce document présente des essais réalisés sur des déchets de ce type visant à corréler ses propriétés mécaniques et hydrauliques. Des essais de compression couplés à des mesures de perméabilité au gaz ont été réalisés sur un déchet provenant d'un forage dans un casi...