Grant: Discovery Grants Program - Individual

Despite our best intentions and efforts to reduce and divert waste, the most recent data from Environment and Climate Change Canada shows that Canadians disposed of nearly 2 kg of solid waste per person per day in 2018. Containment in landfills will continue to be essential for the foreseeable future to manage this enormous amount of waste in an environmentally acceptable manner. If anything, better performing and longer lasting landfills will be needed to protect the health of humans and the environment from a harmful group of man-made `forever' chemicals (PFAS) because of their persistency and high concentrations relative to water standards. An engineered cover on top of historical and future waste is essential to limit infiltration of water into the waste. This minimizes the leachable contaminants made available for transport to the surrounding environment. We know that geosynthetic liners (man-made out of plastic and clay) can be very effective at limiting infiltration through waste covers; however, we do not know for how long they last. This is because differential settlement of the cover, caused by uneven movements of the underlying waste, leads to physical demand on the geosynthetic liner (tension) that can cause it to rupture and leak.      The overarching vision of the proposed research program is to create new fundamental engineering science knowledge, train 12 highly qualified personnel, and develop rational and practical tools to establish at what level of physical demand from differential settlement will geosynthetic cover liners start to leak. The research team will devise, conduct, and interpret results from: i) full-scale laboratory experiments (physical models) to establish modes and magnitudes of deformation; ii) element tests to measure impact of tension on material response and performance; iii) numerical models to provide new insight into the measured physical response, and to prepare parametric studies for practical waste containment scenarios; and iv) field experiments to investigate the effectiveness of remediation techniques. The research is needed by designers, regulators, and community stakeholders to identify when failure occurs, what can be done to extend performance, and how failure can be detected and mitigated. The findings are expected to improve material selection and construction details for new covers. The results will be used to develop monitoring programs for existing covers and establish remediation plans for covers with unacceptable performance.      This research program will also provide exceptional training opportunities for 12 highly-qualified personnel (4 PhD, 3 MASc, 5 BASc) with specialized geosynthetic liner and waste containment expertise that is in very high demand by geotechnical engineering consultants.