"EDMONTON -- Geotechnical engineers remained at the Obed Mountain coal mine Sunday trying to determine how one billion litres of murky water leaked from a containment pond into the Athabasca River."

"A barrier gave way on Halloween, allowing liquid containing coal dust, sand and dirt to flow through two creeks into the Athabasca, said Darin Barter, a spokesman for the Alberta Energy Regulator.

'I haven’t seen this happen. Coal mine incidents and pit leak incidents are really rare,' he said. 'I was surprised this could happen.'"

Gordon Kent reports for the Edmonton Journal November 4, 2013. [2]

SEE ALSO:

"Critics Lash Out at Government Response To Coal Mine Spill Into Athabasca" (Edmonton Journal) [3]

"Hinton Coal Mine Leak: Alberta Pit Failure Dumps Plume Of Refuse Into Athabasca River" (Huffington Post) [4]

"‘Major Failure’ of Coal Mine Pit Releases Waste Water Into Athabasca River" (Global News) [5]