For large landfills, secondary liner systems are required to provide the subsurface additional protection from the contaminants. In this case, usually gravel is used as the secondary leachate collection system. This research studies different types of geotextiles forming part of geocomposite drains (GCD) sometimes used as a replacement for gravel in a leak detection system between two liners. The GCD is often promoted as having the advantage of potentially reducing strain on the underlying layers, but clogging and long-term performance of these geosynthetics are still two factors to be studied in a serious manner. The geotextile forming part of the GCD is crucial in this regard. The objective of this study is to investigate the service life of three geotextiles, all elements of GCDs intended for use in landfill applications. The geotextiles examined are gray, nonwoven, and have needle-punched polypropylene staple fibers. Produced by different manufacturers, they have different mass per unit area. The geotextiles are immersed in simulated municipal solid waste leachate and incubated in ovens at four temperatures. Samples are taken at regular intervals and tests conducted on the aged and unaged samples. Tensile and puncture tests are performed to assess changes in physical properties with aging. Changes in the performance are measured by comparing the aged values with the unaged values. The initial evaluation of the apparent rate of degradation in tensile and puncture tests are reported.
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