NEWS 2013

Posted January 17, 2013

Event: January 24, 2013

GSE: Dr. David C Sego, P.Eng., Professor Emeritus, University of Alberta - Thermal Behavior of Waste Rock Pile(s) Located in a Continuous Permafrost Region at Diavik Diamond Mine

Location: Faculty Club, University of Alberta

Time: 11:45am - 1:30pm

Cost: $30 Members, $40 Non-Members, $10 for Students

An on-going field study at the Diavik Diamond Mine, NT, Canada, is examining the hydrology, geochemistry, microbiology, gas transport, and heat transport mechanisms controlling acid rock drainage (ARD) in low sulphide waste rock the Canadian Arctic. The mine is located in the continuous permafrost zone. This presentation will provide background to the overall study with a major focus on the thermal behavior within the test piles and a large-scale waste rock pile. Three test piles are used to provide detailed measurements to study the evolution of the gas transport, hydrology, thermal and geochemistry. These piles are highly instrumented and data has been collected since 2006. Three drill holes to 40 m depth are used to monitor temperature inside the full-scale waste rock pile, beginning in July 2010. Temperatures measured at 5 m spacing indicate that the 0-degree Celcius isotherm is currently at 10-11 m below the top of the pile, reflecting thermal conditions following pile construction. The evolution of temperatures in the various piles will be discussed to enhance our understanding of the closure options and the potential impact of climate change on these options will be reviewed.

Dr. Sego, P.Eng. is a Professor Emeritus, Civil & Environmental Engineering at the University of Alberta. He holds a BSc and PhD in Civil Engineering from the University of Alberta. He held an academic appointment between 1977 and 2010.

Dr. Sego has over 40 years of experience in Cold Regions Engineering with a focus on the behavior of permafrost and design of foundations in cold regions. Ongoing studies on the fundamentals of soil freezing have been undertaken to better understand the mechanics of frost heave in soil and the development of unfrozen water within both freezing and frozen soils. He also has carried extensive experience in behaviour and management of mine wastes in Cold Regions.