Testing of Materials for Use in the Lining of Waste Disposal Facilities

Abstract

The lining of waste disposal facilities with materials of low permeability is a feasible means of preventing potentially polluting constituents in wastes impounded on the land from seeping out of the impoundment and entering the groundwater. A great array of materials, including fine-grain soils and clays, asphaltic compositions, concretes, and polymeric membranes, are potential candidates for use as liners. The use of materials for lining waste impoundments and disposal facilities is comparatively new, and experience in their field performance is limited. Considering the variety of lining materials that are available and the vast number of compositions of the waste streams that must be impounded, a body of test methods is needed to: (1) guide the selection of liners for specific applications, (2) assure that the quality of the liner that has been selected is placed on the site, and (3) monitor the condition of the liner during service. This paper discusses the test methods that are currently available for use in liner technology, and describes an overall approach to the testing of liners, principally membrane liners. Emphasis is placed on tests needed for liner selection and impoundment design. Of particular interest are the descriptions of several tests designed to simulate the conditions of service of liners in actual waste impoundments. Data from two ongoing Environmental Protection Agency (EPA) liner research projects are presented to illustrate the tests that are described.