National Public Radio: Government regulators in Canada are investigating a series of mysterious oil spills around tar sands operations in Alberta. Thick oil is gurgling up unexpectedly from the ground instead of flowing through the wells that were built to collect it.
The spills are raising questions about a technology that's rapidly expanding to extract fossil fuels that could ultimately end up in the controversial Keystone XL pipeline.
The extent of the spills is small, compared with the huge open pits and slag...