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A composite liner comprised of a fluorinated high-density polyethylene (f-HDPE) geomembrane and geosynthetic clay liner (GCL) was used to contain a hydrocarbon spill in the Canadian Arctic. Results of laboratory tests conducted to assess the effect of exposure to cold climates and hydrocarbons on the performance of the GCL and f-HDPE geomembrane with time are reported herein. The effect of freeze–thaw conditions on the short-term low-gradient and the long-term high-gradient hydraulic conductivity of unfrozen GCL specimens is examined with respect to permeation by Arctic diesel (jet fuel). The hydraulic conductivity of frozen GCL specimens is also discussed. The effect of contact with jet fuel on the chemical and mechanical properties of the geomembrane is reported. Finally, the implications of these extreme conditions on the likely performance of the composite liner are discussed. [Copyright &y& Elsevier]

Abstract: A series of fluorinated high density polyethylene (f-HDPE) geomembrane (GM) samples of different thickness (1, 1.5 and 2.5mm) was exhumed from the backfill immediately upstream of a barrier system constructed to contain a hydrocarbon spill in the Canadian Arctic. The samples were tested for oxidation induction time (OIT), crystallinity, melt index (MI) and tensile properties. The results of these tests are reported and it is shown that the durability of the GM was maintained well beyond the initial 3-year design life of the barrier system. Based on 7 years of field data, the std-OIT depletion time for the 1.5mm thick GM used in the barrier system was inferred to be over 140 years while the antioxidant depletion time based on the HP-OIT is estimated to be about 200 years. No significant temporal changes in the crystallinity, MI or tensile properties of the exhumed GM samples were detected. [Copyright &y& Elsevier]