Frozen Core Tailings Dam: Part 1, Long-Term Thermal Performance

Author(s): 
Maritz Rykaart, Peter Luedke, Christopher Stevens
Date: 
Tuesday, October 2, 2018
First presented: 
Tailings and Mine Waste Conference 2018
Type: 
Published paper
Category: 
Geotechnical
 

Tailings management at the Hope Bay Project in Nunavut, Canada, includes reliance on an innovative frozen core dam. This dam does not have a tailings beach against it and has been designed as a water retaining dam with a 30-year design life. Successful performance of the dam relies on both the core and the underlying foundation maintaining specific target temperatures throughout its service life. This paper, which is the first in a two-part series, describes the dam performance six years post construction, and compares modelled thermal response with field performance data collected from multiple ground temperature cables. The data and modelling confirm that the dam has performed in accordance with expectations and that it is on track to meet long-term performance targets, including for conservative climate change scenarios. The second paper in this series describes creep deformation of the dam, which uses the thermal response as a key parameter.

Feature Author

Dr. Maritz Rykaart

Maritz has undergraduate and Masters degrees in Civil Engineering, a PhD in Geotechnical engineering and 21 years of experience in mine management and applied research. His experience includes geotechnical field investigations; geotechnical analysis; environmental audits; landfill siting and design; siting design, construction, operation and monitoring of pollution control systems, water supply dams, tailings impoundments and river diversions; optimization of mine water balances; permafrost engineering; and mine closure planning, design and cost estimating; construction management, quality assurance and quality control, including managing EPCM contacts.

 

Geotechnical Engineering Specialist
PhD, PEng
SRK Vancouver
Dr. Christopher Stevens
Christopher Stevens, PhD., is a geocryologist who specializes in permafrost and cold regions work. He has 8 years of project and research experience in both terrestrial and subsea permafrost, for mining, highway infrastructure, utility corridors, and oil and gas projects in USA and Canada. His experience includes thermal analysis, terrain and climate analysis, permafrost and ground ice characterization, talik delineation, permafrost-groundwater interactions, design and implementation of permafrost monitoring programs, and numerical thermal modeling to assess thermal performance of infrastructure and potential impacts to the environment. His experience also extends to the design and evaluation of permafrost mitigation techniques used to achieve infrastructure and site stabilization in areas with ice-rich permafrost, including passive thermosyphons, active ground freezing, air convection, and thermal covers. Christopher has developed several novel satellite and ground-based geophysical applications for mapping degrading permafrost conditions and characterizing related environmental changes.
Geocryology and Cold Regions Specialist
PhD. Geology and Geophysics
SRK Alaska
SRK Africa