Workshop 1: Remediation (1) Chairman: Professor Luiz Guilherme de Mello, Vecttor Projetos São Paulo, Brazil Discussion leader: Mario Manassero, Land, Environment and Geo-Engineering Department, Engineering Faculty, Politecnico di Torino, Torino, Italy This workshop is devoted to an overview of research activities and new technologies for polluted subsoil remediation. Panellists' papers will cover most new remediation technologies, while the introductory lecture will deal with the extraction of multiphase pollutants under high vacuum pressure and the related governing phenomena. It will focus on a new vacuum extraction system, the integrated geotechnical system for insitu remediation of polluted soils, which is being investigated by a group of Italian universities.
Panellists and presentations:
Professor Akram N Alshawabkeh, Northeastern University, Boston:
Electrochemical soil and groundwater remediation.
Jeremy Birnstingl, managing director, Regenesis, UK: Chemical oxidation - the new bioremediation- Myths and realities.
Professor Albert Yeung, the University of Hong Kong: Electrokinetic remediation: past, present and future.
Professor Mark Dyer, University of Strathclyde, Glasgow:
Bioremediation: concepts and case studies.
Workshop 2: Testing and monitoring (1) Discussion leader: Professor Ademalek Bouazza, Monash University, Melbourne The introductory presentation will provide an overview of the papers submitted to the session: 21 were received from 12 nations on six continents. The papers cover three main topics: barrier materials, mechanics of waste and site investigation. They address chemical compatibility, geosynthetics, desiccation cracking, gas ow, LNAPL movements in unsaturated soils and the geotechnical properties of waste materials.
Panellists and presentations Marina Pantazidou, National Technical University of Athens:
What kind of restoration actions are (a) possible and (b) desirable on the basis of landfill monitoring data- .
Professor Hangseok Choi, Korea University, Seoul: Slug test analysis to evaluate hydraulic conductivity in vertical cut-off walls.
Francesco Mazzieri, Università Politecnica delle Marche, Ancona, Italy:
Chemically enhanced bentonites: addressing the impact of strong electrolyte solutions and dry-wet cycles on the hydraulic performance.
Professor Pierre Delage, CERMES, Ecole Nationale des Ponts et Chausees, Paris: Retention and transport of a hydrocarbon in a silt.
Workshop 3: Barrier design including nuclear waste disposal Discussion leader: Professor Maria Eugenia Boscov, University of Sao Paulo, Brazil The - rst presentation in this session will introduce discussion issues concerning the hydraulic performance and efficiency of vertical barriers. Attention will be focused on the self-hardening cut-off wall, a technology that, if properly designed and constructed, can give a good performance in terms of confinement of pollutants (abandoned land-lls, polluted soils).
The second speaker will discuss the system of barriers in a deep geological repository for high-level radioactive waste to prevent possible escape paths for radionuclides to the environment, the most important of which is the circulation of groundwater.
Panellists and presentations Professor Evelina Fratalocchi, Technical University of Marche, Ancona, Italy: Hydraulic performance of vertical barriers.
María Victoria Villar, CIEMAT, Madrid: Engineered barriers in high-level radioactive Workshop 4: Mine sites, tailing dams, sludge ponds and underwater geoenvironmental issues Discussion leader: W David Carrier, III, Argila Enterprises, Lakeland, Florida A wide range of topics is covered in the papers of this session under four major themes: acid mine drainage; capping and stabilisation; coal; and geotechnical properties of fine-grained slurry materials.
Acid mine drainage includes design of covers to shed rainfall, covers to reduce oxygen inow, bioremediation with sulfate-reducing permeable reactive barriers, and a two-step neutralisation process to reduce the volume of precipitates.
Capping and stabilisation includes geotextile dewatering of slurry, electrokinetic geosynthetics and geogrids/geosynthetics for construction on very soft to extremely soft soils.
Coal is the primary mineral in many of the papers. But the geotechnical properties of other mineral slurries are also described, including the - ne wastes from sand and gravel, iron, gold, peat, uorspar, y ash and nickel.
Panellists and presentations Professor Luiz Guilherme de Mello' Vecttor Projetos São Paulo, Brazil: Discussion of important topics related to Brazilian tailings.
Gijs D Breedveld, Norwegian Geotechnical Institute, University of Oslo: Capping of contaminated sediment - a sustainable solution.
Professor David Williams, University of Queensland, Brisbane: Potentially contaminated seepage from stored mine wastes during operation and post-closure.
Workshop 5: Sustainability, regulation and risk management Discussion leader: Professor Stephan Jefferis, Environmental Geotechnics, UK A key issue for industry is: fiHow do we as a geoenvironmental community measure success in addressing the challenges presented by sustainability- fl Sustainability is not an absolute scale; one project is not necessarily sustainable compared with another;
however after examining certain indicators it is possible to say one is more sustainable than another.
Similarly, risk cannot be judged on an absolute scale but risk assessment can help engineers make difficult choices. Sustainability assessments are largely unconstrained, but inaction now will lead to government imposition later.
Papers will address assessment of contaminated soil and groundwater and subsidence from underground mining. Sustainability brings discussions on materials for geotechnical work; e-business and the geoenvironment; durability of natural geotextiles; predicting the ecological environment for a residential community;
and lessons from Chernobyl. What goes on after figeofl work is - nished will have much greater impact on sustainability. A little more money spent at the high impact figeofl stage may bring long-term benefits.
Panellists and presentations Professor RK Srivastava, Civil Engineering Department, MNNIT Allahabad: Sustainable development - the Indian experience.
Professor Márcio de Souza Soares de Almeida, COPPE/UFRJ, Rio De Janeiro: Electrokinetic injection of nutrients: a laboratory case study.
Professor William Powrie, School of Civil Engineering and the Environment, University of Southampton: In-ground disposal of waste.
Professor Rolf Katzenbach, Institute and Laboratory of Geotechnics, Technische Universität Darmstadt:
Recent German experiences with sustainability in the context of geoenvironmental issues.
Workshop 6: Fate and transport of pollutants Discussion leader: Professor Antonio Gens, Technical University of Catalunya, Barcelona The introductory presentation describes analysis of the potential transport of contaminants in a storage facility for low and medium level radioactive waste. The waste is enclosed in concrete containers which are put in storage units placed on the surface with the spaces between filled with gravel. The storage unit is subsequently covered by soil. The modelling seeks to determine the amount and rate of waste migration out of the facility as a consequence of water infiltration from the surface.
From the results of the numerical analyses, the effect of the position of the water table, concrete and soil permeability, and infiltration rate are evaluated. Particular attention is given to the potential usefulness of providing a drain under the base of the storage unit.
Panellists and presentations Professor Arnold Verruijt, Delft University of Technology, the Netherlands: Three-dimensional transport in a layered porous medium.
Andrea Dominijanni, Studio Geotecnico Italiano, Milano:
Transport properties of electrolyte solutions in bentonite.
Peter Van Impe, Laboratory of Geotechnics, Ghent University, Belgium: Use of low-volume continuous EC probes to increase the accuracy of column testing.
Professor Hywel Thomas, Geoenvironmental Research Centre, Cardiff University: Coupled modelling processes.
Workshop 7: Waste reuse and waste management Discussion leader: Professor Takeshi Katsumi, Graduate School of Global Environmental Studies, Kyoto University Waste reuse and management is one of the most important subjects in environmental geotechnics, covering containment, engineering properties of landfi lled wastes, reuse of waste materials in geotechnical applications and waste stabilisation and reduction.
The introduction to the session will look at site selection and site suitability assessment using GIS and geophysical methods. It will also examine the geotechnics of paste tailing and slurry-pond embankments to maximise the efficiency of mine waste disposal.
Papers on the engineering properties of landfi lled wastes focus on compressibility, effect of aging, seismic response and stability.
Some of the waste materials exhibit excellent engineering properties, and thus have been used in geotechnical applications such as embankments, pavement bases, filling, reclamation and ground improvement.
Recent research has attempted to promote their use, which is reflected in many of the papers. Waste materials covered range from the traditional to those new to geotechnics.
Many studies focus on constructability and engineering properties, including strength developments and deformability. Environmental suitability and landscape are also discussed. And, since regulatory aspects are very important in promoting geotechnical recycling, Japanese case histories are examined.
The papers covering waste stabilisation and reduction examine waste sludge and stabilisation of residue ground from heaving.
Finally, the presentation will provide a brief review of waste reuse and management, in particular in terms of engineering properties, innovative applications, environmental suitability and regulatory issues.
Panellists and presentations Russell Jones, principal and technical director, Golder Associates (UK): Engineering properties of waste:
what we know and what we need to know.
Professor Sudhakar M Rao, Indian Institute of Science, Bangalore:
Reuse of toxic sludge in civil engineering applications.
John McDougall, Napier University, Edinburgh: Hydrobiomechanical modelling of landfilled waste.
Professor Tuncer B Edil, University of Wisconsin-Madison, US: Beneficial use of industrial by-products.
Workshop 8: Remediation (2) Discussion leader: Professor Jorge Zornberg, University of Texas, Austin Contributions to this session cover a wide range of important topics with four main themes: biodegradation processes, electrokinetic technologies, insitu containment and stabilisation.
These technical areas are complemented with economic assessment evaluations.
Advances in bioremediation techno ogies include their use in cyanide-contaminated soils, the assessment of transformation and transport rates of a biodegradable additive, the efficacy of electrolytic generation of oxygen for biodegradation and biological denitrification using permeable reactive barriers.
Reported advances in electrokinetic technologies include remediation of soils contaminated with heavy metals, lead and a mixture of contaminants (when combined with chemical oxidation).
Signifi cant breakthroughs in insitu containment include the use of cement-bentonite cut-off walls in acidic sulphate environments, the compatibility of slag-cement-bentonite not only with sulphates but also with organic contaminants, as well as the use of glacial deposits to isolate heavily polluted soft marine sediments.
Advances involving stabilisation include the remediation of lead-contaminated residual soils achieved by solidification as well as the use of zeolite-sand mixtures for permeable reactive barriers.
Papers addressing the economic impact of remediation include the characterisation of large deposits of fl y ash for reclamation areas, the assessment of remediation effi ciency for old landfills and a report on European remediation technology costs.
As the rate of our ability to pollute continues to increase, it is at least encouraging that the rate of advances in remediation technologies also continues to expand.
Panellists and presentations Roger Clark, director, CL Associates, UK: The changing face of remediation in the UK.
Dimitris Dermatas, Stevens Institute of Technology, New Jersey: Phosphate application to firing range soils for Pb immobilisation: the unclear role of phosphate.
Krishna R Reddy, University of Illinois at Chicago:
Remediation of contaminated sediments.
Stefano Veggi, Studio Geotecnico Italiano, Italy: Construction techniques and efficiency assessment of cementbentonite slurry cut-off wall for pollutant containment.
Workshop 9: Testing and monitoring (2) Discussion leader: Kenichi Soga, University of Cambridge Understanding and prediction of long-term performance of geo nvironmental infrastructure are becoming increasingly important because of the social demand for life cycle costing and environmental impact analysis of construction.
Although geotechnical engineers appreciate the time-dependent nature of soils as well as environmental effects, engineering analysis of long-term performance of geoenvironmental infrastructure is often not performed because of limited understanding of its long-term behaviour.
Innovative testing and monitoring technologies are needed to increase understanding of this behaviour.
This session will discuss case studies of landfi ll performance in the field; longterm deformation of landfi lls; use of geophysics to assess the performance of geoenvironmental infrastructure; long-term and environmental effects on engineering properties of geomaterials; and testing methods to evaluate long-term performance.
The introductory talk will provide a few examples of long-term effects of geoenvironmental processes and address the need for understanding the mechanisms of these effects and for implementing innovative techniques for long-term monitoring.
Panellists and presentations Craig Lake, Dalhousie University, Canada: Testing and monitoring of geosynthetic clay liners for basal liner applications.
Professor Jean-Pierre Gourc, University Joseph Fourier, France: Overview of landfill instrumentation techniques for the monitoring of waste settlements.
Guido Musso, Politecnico di Torino, Italy: Geoenvironmental laboratory characterisation by means of electrical impedance tomography.
Douglas I Stewart, University of Leeds: Characterising the microbial communities in soils from contaminated sites.