Steam Injection Fractures Caprock in Big Alberta Spill, Regulator Says

"Three years after an eruption of 10,000 barrels of melted bitumen contaminated the boreal forest and groundwater near Cold Lake, Alberta, the provincial energy regulator has now officially blamed hydraulic fracturing, or the pressurized injection of steam into the ground for fracturing nearby rock.

The bitumen blowout occurred sometime between May and June 2013 at Canadian Natural Resources Ltd.'s Cold Lake project, an operation that uses steam injection to melt bitumen and bring it to the surface.

In this case, the pressure from the steam cracked rock between different formations, allowing melted bitumen to find natural fractures and flow to the surface at five different locations, including under a lake.

In some places, the bitumen erupted through fissures in the ground as long as 159 metres deep."

Andrew Nikiforuk reports for The Tyee March 23, 2016.