A multiphase experimental research program involving large diameter (525 mm) test columns is currently being conducted at SNC's Advanced Materials Testing laboratory in Saskatoon. The objective of this study is to investigate the effectiveness of vertical strip drains (VSD) in enhancing dewatering of mature fine tailings (MFT). The two phases of this test program and preliminary (approximately 65 day) results are described in this paper. The Phase I part of this program involves self-weight consolidation of the MFT in a large diameter test column containing a central VSD. Self-weight consolidation is the process where the slurried tailings are deposited into a pond or holding facility and allowed to settle under their own weight. Settlement under these conditions takes place through a combination of sedimentation and consolidation. This is a slow process which may take many years. In order to speed settlement, the tailings are frequently subjected to loading by covering them with a cap or through the use of dewatering techniques The Phase II part of this test program involves application of surcharge load on a similar MFT tailings filled test column containing a central VSD. This surcharge load is used to simulate the effects of capping an MFT tailings facility. It also enables the simulation of the stress condition of the tailings at lower depths within the tailings pond. The MFT used in this test program was obtained from Suncor's Pond 5 at Fort McMurray. This MFT has a sand-to-fines ratio of 0.18 and an initial solids content of 46.7%. Design and layout of columns in Phase I and Phase II, and preliminary results are presented in this paper.
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