Published Online: 17 May 2013
Page Count: 9
Chapuis, Robert P.
Dept. of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, Montreal, PQ
(Received 22 October 2012; accepted 22 March 2013)
This paper examines the performance of three compacted clay liners for holding and treating municipal wastewater in three lagoons. The quality controls for the liners included verification of compaction conditions (dry density and water content) and full-scale leakage tests. These were made by filling each lagoon with clear water and monitoring the leakage rate versus water level in the lagoon. This paper presents the quality control data, the predicted local values of the hydraulic conductivity k versus void ratio e, and degree of saturation Sr as achieved by compaction, and a statistical prediction of the large-scale k value for each liner. For this case history, one full-scale test was performed before winter and the measured large-scale k value agreed with the predicted value. Two full-scale tests were performed the following spring, and revealed that frost had seriously damaged the liners of the two lagoons, which had been left empty during winter. The paper thus validates a previously proposed model for predicting hydraulic conductivity, and it also provides a statistical approach to predict the large-scale k value of undamaged clay liners.
Paper ID: GTJ20120198