Evaluation of Geomembrane Destructive Seam Testing Frequencies and Risk Management

An increasing demand for construction quality assurance (CQA) for large landfill liner and final cover projects is being driven by three key recent trends: (1) the consolidation and closure of large municipal solid waste (MSW) landfills; (2) the expansion and/or closure of large coal combustion residual (CCR) landfills, and (3) the closure of large CCR surface impoundments. The unprecedented size of these emerging construction projects is cause to examine existing CQA practices and evaluate their projected efficacy for upcoming construction. Destructive seam testing for geomembranes deployed in the field is an area of particular interest because this kind of CQA testing has a direct impact on the quality, schedule, and cost of installations. This paper examines available probability-based quality assurance methods and considers their impact on risk of poor performance for large liner and final cover systems. Data from completed projects are used to illustrate the implementation of these methods and to simulate how a CQA program can manage risk.