Nexen pleaded guilty to one count under Alberta’s Environmental Protection and Enhancement Act for a July 2015 oil spill at its Long Lake facility.
The company has been ordered to pay $460,000.
READ MORE: Nexen’s Fort McMurray pipeline spill one of Canada’s biggest ever
“This spill was one of the largest in Alberta’s history,” said Jim Ellis, president and CEO of the Alberta Energy Regulator (AER).
“Over the last three years, we’ve kept a close eye on Nexen’s operations to bring the company back into compliance.
“The pipeline responsible for this spill will remain suspended until Nexen can demonstrate to us that the company can operate it safely.”
Nexen will have to get written approval from the AER to operate this particular pipeline again.
The spill happened about 45 kilometres southeast of Fort McMurray.
It leaked an estimated 5,000 cubic metres of emulsion – about five-million litres of bitumen, sand and wastewater – over a 21,900-square-metre area.
READ MORE: 5 charges laid against Nexen for massive July 2015 Long Lake pipeline spill
In July of last year, the AER laid five charges against Nexen for the spill.
The charges relate to releasing a substance that may have caused an adverse effect and disturbance to public lands, failing to report the release as soon as possible and failing to take all reasonable measures to remediate, and manage the spill.
READ MORE: What is bitumen emulsion?
Nexen conducted its own investigation into the pipeline rupture, concluding that the design was incompatible with the ground conditions and buckled as the temperature fluctuated.
Nexen’s automatic detection system didn’t detect a ruptured pipeline and a contractor walking the pipeline discovered the leak.
Out of the $460,000 penalty, $19,983 is a fine and the rest is considered “creative sentencing,” AER said. It will help pay for a learning centre focused on pipeline best practices. In addition, $220,000 will expand an environmental sciences degree program for Indigenous youth.
In addition to the provincial penalty, Nexen pleaded guilty to charges under the federal Fisheries Act.