Geosynthetic clay liners in alkaline environments

Conference · Sat Nov 01 04:00:00 EST 1997

OSTI ID:543568

McKelvey, III, J A ^[1]

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1. Roy F. Weston, Inc., West Chester, PA (United States)

The use of geosynthetic clay liners (GCLs) as secondary barrier layers in environmental applications such as landfills and other impoundment facilities is becoming increasingly more popular among the engineering community, particularly at project sites where earthen materials suitable for barrier layers may not be locally available. Design engineers for these environmental applications are becoming well versed at performing equivalency calculations comparing the performance of geosynthetic materials to their earthen counterparts. For barrier layers, these equivalency calculations would normally compare the mechanical and hydraulic properties of the GCL to a compacted clay liner. Of these properties, the ability of the hydraulic properties to withstand degradation due to permeation of contained leachates is of prominent concern. Such is the case in alkaline environments. The leachate may adversely affect the GCL by minimizing swelling, decreasing adsorption capacity and increasing the permeability of the material. If the effect on the material is significant, the usefulness of this product is diminished, possibly voiding any equivalency comparison to compacted clay liner performance. The design engineer must fully understand what effect, if any, specific leachates will have on the GCL being considered. Accordingly, appropriate performance testing with the leachate in question must be performed during the design phase and confirmed during construction through quality assurance testing. This paper will present the design considerations, required laboratory testing and conformance tests for a recent project that contained an alkaline leachate. Through appropriate testing, a contaminant resistant GCL was shown to possess desired hydraulic properties in the presence of the alkaline leachate.

• OSTI ID: 543568
• Report Number(s): CONF-9601137--; ISBN 0-8031-2471-6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
ACID MINE DRAINAGE
CORROSION RESISTANCE
HYDRAULIC CONDUCTIVITY
LEACHATES
LINERS
PERFORMANCE
PH VALUE
REMEDIAL ACTION
SANITARY LANDFILLS
SLUDGES
WATER TREATMENT