Alberta floods blamed for ruptured pipelines

25 June 2013

Enbridge Inc., Canada's largest pipeline company, said on June 22 that 750 barrels of synthetic oil had spilled from a pipeline serving CNOOC's Long Lake oil sands project. Enbridge said it was still investigating the cause of the spill near its Cheecham terminal, about 70 km (43 miles) southeast of Fort McMurray, Alberta.

The company said that it had also shut down two major oil pipelines serving Canada's oil sands region as a precaution. Shipment on the 345,000 barrels per day Athabasca pipeline and the 350,000 bpd Waupisoo line have been suspended while the company investigates the cause of the Line 37 spill. It gave no estimate for when the lines would re-open.

Enbridge said recent heavy rains in the region may have resulted in ground movements that affected the pipeline. It is working with regulators to assess the cause.

Earlier, a pipeline carrying deadly sour natural gas ruptured in southern Alberta, causing the evacuation of some of the town of Turner Valley's 2,100 residents, the Alberta energy regulator said.

The regulator said it is working with pipeline owner Legacy Oil and Gas Inc and the authorities in Turner Valley, about 60 kilometers (37 miles) southwest of Calgary, to respond to the June 20 leak. The gas contains 1% hydrogen sulfide.

While no injuries have been reported, hydrogen sulfide can cause serious injury or even death at levels as small as 100 parts per million. In smaller doses, it will cause irritation to eyes, nose and throat.

Turner Valley and many other municipalities in southern Alberta, including the city of Calgary, had already declared states of emergency as heavy rains swelled rivers and streams and forced the closure of the TransCanada Highway, the country's main east-west route, near Canmore, 100 kilometers west of Calgary.

Legacy Oil and Gas said in a statement the leak had been caused by impacts from trees and other debris on a flow line in rising floodwater. The line is attached to its natural gas well, Royalite 19, in the Turner Valley.

The company said it was in the process of shutting down the line at the time due to the flooding.

According to Reuters, Legacy said its own air quality monitoring had not detected levels of hydrogen sulfide that would "exceed regulated levels for public health."

At least three people have been killed and more than a 100,000 forced to evacuate their homes in western Canada as a result of the floods.