Oil sands geotechnique

Oil sands mining

The oil sands surface mining region (Google Earth, January 2017)

 

Surface mining of the oil sands requires a very broad range of geotechnical skills employing 100 to 200 geotechnical specialists (staff and consultants) at the major mines;

  • CNRL Horizon Mine
  • Imperial Kearl Lake Mine
  • Shell Muskeg River Mine and Jackpine Mine
  • Suncor Base Mine, Steepbank Mine,¬†Millenium Mine, and Fort Hills Mine
  • Syncrude Mildred Lake Mine and Aurora North Mine

 

A list of the geotechnical challenges for oil sands mining is provided by McKenna (1998):

  • dam construction on muskeg foundations
  • spillway design and maintenance on weak valley slopes
  • heavy foundations on gassy and temperature-sensitive soils
  • coring and testing of gassy/expansive oil sands and haul roads
  • trafficability for large mining equipment on oil sands
  • depressurization of watersand aquifers
  • failure of starter dykes and movement of tailings dykes on clay shale foundations
  • highwall design utilizing locked sands
  • winter construction of large fluid retaining embankments
  • design of landfills and sewage treatment plants
  • frost effects on foundations and stockpiles
  • short and long-term excavations into clay shale slopes
  • cold-weather construction of tailings
  • blockslides along inclined clay layers
  • progressive failure in sands and clays
  • empirical highwall monitoring for draglines
  • highwall failures due to gas-exsolution and bulging
  • pit-floor heave
  • concerns of static liquefaction of loose tailings sands
  • use of lean oil sand as a construction material
  • ore stockpile failures on weak clay layers
  • characterization and management of fluid fine tailings
  • failure of in-pit dumps due to collapse of clay shale fills
  • movement and failure of out-of-pit dumps on clay shale
  • long-term physical stability of reclaimed landscapes

 

The mines each have a geotechnical review board. I presently sit on the Shell review board (the Shell Tailings and Geotechnical Advisory Panel along with Drs Norbert Morgenstern and Leslie Smith). My article on one review board¬†(Celebrating 25 years: Syncrude’s Geotechnical Review Board) from 1998 is a bit dated now, but still a good read).

 

oil sands mining geotechnique

Oil sands overburden waste storage area with a external tailings facility in the background (2014)

 

 

Most of my career has been focussed on oil sands geotechnique — from pit wall stability, to foundations, to tailings R&D, closure planning, and reclamation operations. I try to bring learnings from my other mines to oil sands and disseminate learnings back out to the world.