ABSTRACT
Increasing amounts of waste and the growing need for public awareness of possible pollution caused by landfills make it necessary to develop strategies to protect the environment from waste and its components. Several techniques and systems have been developed, which use either natural substances or technical material (fibre), or both, to achieve a high degree of security. The two main factors which must be considered when using these materials for lining landfills are the limitations of mechanical stability and the hydrological conductivity of fluids. Despite strict regulations regarding these materials, a number of cases have been repor ted which describe the problem of environmental pollution despite compl iance within certain limits. Furthermore, the costs of planning and cons truction are often a point of discussion which may influence the standard of security. A major question that has to be dealt with is, therefore, not only the properties of capping systems but also their sustainability. This chapter summarizes the various aspects which must be considered when using natural substances or fibres for securing landfills, and proposes the capillary capping system as a possible design for long-term efficiency.
