Waste Containment: Strategies & Performance

This paper reviews strategies for lining and covering waste containment systems, as well as systems used to remove leachate. Emphasis is placed on factors influencing field performance. Field performance data indicate that compacted clay liners and composite liners are performing as intended, and that their performance can be predicted with standard calculation methods. Resistive covers employing a soil barrier with low saturated hydraulic conductivity as the primary impedance to flow have been shown to perform poorly due to the effects of desiccation and frost action. Covers with a composite barrier layer or water balance covers have a much better performance record, and can effectively eliminate percolation into waste. The performance of leachate collections systems ranges from poor to excellent depending on the design and materials of construction. Successful leachate collection systems are constructed with coarse uniformly graded gravel with little fines and are overlain by a non-woven geotextile filter.