Landfill Closures

It is toward investigating, discussing and presenting the various issues involved in solid waste closure that this book is focused. It consists of invited papers presented at the 4th Annual Geosynthetic Research Institute Seminar. The closure [capping] of completed or abandoned solid waste facilities present particular challenges, for example: ★ there usually exists a very uncertain and random subsidence behaviour of the existing waste beneath the closure, ★ the friction behaviour of the various interfaces that are involved in solid waste facilities is not established, ★ there are numerous long term geosynthetic stability and durability issues that must be addressed, and ★ there are an extremely large number of sites that require proper closure. These topics are addressed in the three sessions Geosynthetics in Landfill Closures, Interface Friction Considerations and Geocomposites Systems and New Materials. Current materials and basic techniques are reviewed and innovations discussed. Owners' perspectives and design considerations raised and specific problems such as liquid intrusion are addressed. The area of landfill closure simply begs innovation and the manufacturing sector is meeting the challenge. This gathering of expert opinions is an important document of the proper use of geosynthetics in landfill closure systems.

FROM THE PREFACE Sanitary landfills are the most widely utilized method of solid waste disposal around the world. With increased use and public awareness of this method of disposal, there is much concern with respect to the pollution potential of the landfill leachate. Depending on the composition and extent of decomposition of the refuse and hydrological factors, the leachate may become highly contaminated. As leachate migrates away from a landfill, it may cause serious pollution to the groundwater aquifer as well as adjacent surface waters. There is growing concern about surface and groundwater pollution from leachate. Better understanding and prediction of leachate generation, containment, and treatment are needed. This book contains a literature review of various methodologies that have been developed for prediction, generation, characterization, containment, control, and treatment of leachate from sanitary landfills. The contents of this book are divided into nine chapters. Each chapter contains theory and definition of the important design parameters, literature review, example calculations, and references. Chapter 1 is devoted to basic facts of solid waste problems current status and future trends towards waste reduction and recycling. Chapter 2 provides a general overview of municipal solid waste generation, collection, transport, resource recovery and reuse, and disposal options. The current status of sanitary landfill design and operation, problems associated with the landfilling, and future trends are presented in Chapter 3. Methods of enhanced stabilization, recycling landfill space, methane recovery, and above grade landfilling, and closure and post closure care of completed landfills are also discussed in detail. Chapter 4 provides a general overview of Subtitle D regulations and its impact upon sanitary landfilling practices. Chapter 5 is devoted entirely to moisture routing and leachate generation mechanisms. Examples of calculation pr