TransCanada conducting internal probe after crew damaged Enbridge pipeline that leaked

Federal officials and Canada's two largest pipeline companies are investigating a spill of 200,000 litres of oil condensate that was reported on Friday after a construction crew working for one of the companies, TransCanada Corp., appeared to cause damage to an Alberta pipeline that belonged to the other.

The federal energy regulator, the National Energy Board, has also deployed investigators to the scene at Strathcona County, east of Edmonton, as workers attempt to clean up the spill.

The spill, which occurred in an excavation pit on privately-owned industrial land near Enbridge's Edmonton Terminal, is the latest in a series of accidents that are exacerbating public concerns about whether government inspectors are providing adequate oversight of industry.

The incident also comes as both of the Calgary-based pipeline companies involved, TransCanada Corp. and Enbridge, are pursuing proposals to build major pipeline expansion projects such as TransCanada's Keystone XL and Energy East pipelines and Enbridge's Line 3 expansion project.

Pipeline industry officials say that incidents such as these are rare and that most oil and gas products get delivered safely, without spills.

Who was the first to detect the leak?

It was not immediately clear whether TransCanada's construction workers reported the leak before Enbridge's safety systems detected the problem, but both companies told National Observer in separate statements they had responded immediately.

In a note posted on its website, Enbridge said its leak detection systems allowed it to shut down its Line 2A pipeline. Enbridge also said in that statement that the incident occurred during construction work by TransCanada Pipelines and its contractor, Ledcor. TransCanada told National Observer in a statement that its construction crews detected the leak and immediately reported the incident to Enbridge.

"Crews were working on the construction of the Grand Rapids pipeline project when a release was detected," TransCanada spokesman Terry Cunha told National Observer. "TransCanada immediately notified Enbridge who responded to the incident. Currently an internal investigation is being conducted to determine what occurred. TransCanada continues to cooperate with all parties involved."

When asked to clarify whether TransCanada's report came before the alarm indications, Enbridge spokeswoman Suzanne Wilton said: "I can’t speak to what TransCanada did or didn’t do. What I can say, is that Enbridge acted immediately on alarm indications and initiated shutdown of multiple lines as a precaution. The release was confirmed almost immediately and our emergency response also initiated. As I said, Enbridge’s safety procedures worked exactly as they should."

When asked to respond to Wilton's comments, TransCanada's Cunha also reiterated his earlier statement that his company had immediately notified Enbridge about the release when it was detected.

Ledcor didn't immediately respond to requests for comment from National Observer on Monday.

The NEB told National Observer that it would publish a new update about the situation on Tuesday. In a previous statement posted on a federal government website, the NEB, the federal regulator, said that it remains on site to supervise clean-up operations and monitor remediation of any environmental effects caused by the accident.

"There were no injuries, no fire, no evacuations and no risk to public safety," the NEB said in the statement.

Enbridge has also said it is monitoring air quality in the wake of the accident and that after temporarily shutting down some nearby pipelines as a safety precaution, it has restarted all of the lines, except for the one that was damaged, Line 2A.

Whistleblower allegations about TransCanada dismissed by NEB in 2015

Construction damage to pipelines was part of a series of serious safety allegations raised by a TransCanada whistleblower in 2015. But following a probe that was led by NEB chief executive Peter Watson, the regulator dismissed most of these allegations a few months later, concluding that they were mostly unfounded and that TransCanada had addressed all of the safety concerns.

TransCanada, at that time, said in a blog post that the NEB investigation report concluded that the allegations had "no basis in fact whatsoever". The whistleblower said he didn't believe the NEB had adequately investigated his allegations.

In recent months, anti-pipeline activists have criticized the industry in the wake of incidents that caused serious environmental damage and raised questions about the quality of existing leak detection technology. Engineers from industry have said that the current technologies cannot always detect releases of less than two per cent of the volume of oil or gas being transported on pipelines. This means that some spills or leaks might not be detected at all, unless someone spots them on the ground.

A July oil spill on a pipeline operated by Husky Energy in Saskatchewan that affected drinking water supplies for more than 70,000 residents. About 220,000 litres of oil was released from that incident, contaminating the North Saskatchewan River. The company initially gave conflicting reports to the government about when it first discovered the possibility of the leak.

In April 2016, TransCanada was forced to temporarily shut down its Keystone pipeline and clean up after a landowner spotted a spill in South Dakota that released about 64,000 litres of oil into the environment.