Two pipeline oil spills have raised safety concerns over Canadian and US oil distribution at a crucial time for the tar sands pipeline.
The larger of the two spills occurred on 29 April in the Rainbow Pipeline system managed by Plains Midstream Canada which carries oil from North Alberta to Edmonton. Described as the largest spill in the Alberta Province since 1975, around 28,000 barrels (4.5m litres) of light sweet crude spilled from a damaged pipe caused, according to the company, by stress on the pipe after maintenance was not completed properly.
Response teams worked round the clock to contain the spill and prevent it from reaching the nearby Peace River and by 11 May around 36% of the spilt oil had been collected by vacuum vehicles and skimmers, although operations were halted by an emergency distress call which later proved to be a false alarm.
In an entirely unrelated incident, around 500 barrels spilled from TransCanada Corp's Keystone pipeline in North Dakota after a valve failed at a pumping station on 7 May. The spill, in US North Dakota, was mainly contained around the plant, but delays have extended in re-opening the pipeline which was carrying about 20% of Canada's oil exports to the US at the time of the incident.
Most importantly, the two spills have raised concerns with environmentalists including Greenpeace over the safety of Canada's oil pipeline network. The timing is also particularly bad for TransCanada which is looking for US approval for the Alberta-to-Texas Keystone XL pipeline.
The $7bn project is the final stage of the larger 3,800 mile Keystone system, planned to carry heavy crude from Alberta's oil sands patch via six US states to Gulf Coast refineries. The pipeline would cross the Ogallala Aquifer, the largest underground water source in the US and the latest spills are being used as examples in a long-runnng campaign against the pipeline.