Report on Irving Oil butane leak that forced evacuation kept under wraps

Nearly one month after an Irving Oil butane leak in east Saint John forced the evacuation of several homes and businesses, no new information has been released about what caused the leak, when it started or how much butane leaked.

Irving Oil hired a consultant to "assess impacts" and submitted a proposed remedial action plan to the Department of Environment earlier this week, as required, said department spokeswoman Sheila Legacé.

She refused to release the approximately 10-page report, saying "it would be up to the company to release it."

But the document does not contain any details about how long the four-inch diameter pipeline had been leaking liquid butane into the ground and vapours into the air before it was discovered on Jan. 8 by workers who were preparing to do some maintenance in the area, Legacé said.

Some residents who live near Irving's Saint John East terminal on Bayside Drive told CBC News they detected an odour for about three days before the leak was discovered.

An estimate of the amount leaked "is currently being calculated," according to the consultant's report, said Legacé.

Butane is a colourless, highly flammable gas that can cause nausea, asphyxia and arrhythmia if inhaled.

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The leak forced about 84 area residents from their homes, closed the Saint John SPCA Animal Rescue shelter and rerouted traffic around a blocked section of Bayside Drive as emergency responders purged the line and tested for residual vapours. Crews cleared the scene on Jan. 13.

A preliminary investigation suggested the above-ground pipeline, which carries butane from the terminal to the refinery, sustained a "small freeze split" due to extreme cold weather.

"Since liquid butane has a boiling point of 0 C, any liquid butane released during the leak has evaporated, which is why it is hard to determine the quantity of butane leaked," Legacé said in an email to CBC News.

"This is also why the situation was being considered as a fire hazard when the incident occurred and was ongoing."

Pipeline holds 17,000 litres

The pipeline itself holds an estimated 108 barrels, Irving Oil vice-president and chief operating officer Mark Sherman has said.

Each barrel holds about 159 litres, for a total of more than 17,000 litres.

"It looks like a very small amount has come out," Sherman told reporters on Jan. 9, referring to a "small pool" of liquid butane on the ground at River Avenue.

The consultant's report "outlines a plan to do confirmation testing in the soil, air and wastewater systems in the area of the leak to confirm the absence or presence of butane," said Legacé.

"It is anticipated that the testing will show non detect levels of butane. If there is butane detected a plan to address this will be developed on a case by case basis."

The department expects to respond to the company's plan next week, said Legacé.

She did not say whether any information will be made public at that time.

An inspector from the department was dispatched to the site on Jan. 8, met with emergency crews on an ongoing basis during the mitigation phase and "when threats to public safety had been mitigated, impacts to the environment were further evaluated on-site," said Legacé.

But none of the inspector's findings have been released.

EUB probe could take 'months'

The Energy and Utilities Board, which is responsible for licensing pipelines carrying hazardous materials and has the authority to recommend charges to the Crown's office, is still investigating, said spokesman Dave Young.

The EUB has not said what, if any, leak detection or alarm systems the company was required to have or whether those were in place and operational at the time the leak was discovered.

"Unfortunately the board won't be making any more comments while the investigation is ongoing," Young said in an email to CBC News on Friday.

"I am told that this could take a few months."

The EUB wants to determine the cause of the leak, whether procedures were followed, and "what, if any procedures need to be implemented to prevent it from happening again," Young said previously.

The pipeline was approved to resume operations on Jan. 19 after it was repaired, tested for thickness and corrosion and raised to make it less susceptible to constraints during the natural expansion and contraction with temperature changes.

The EUB also ordered a network of continuous leak detection monitors be installed along the length of the pipeline system, which will immediately notify the company's control centre of any issues.

Irving Oil officials have not responded to repeated requests for information.

The refinery uses liquid butane as an additive to pressurize gasoline in the winter, Sherman has said. Without it, vehicles would be very difficult to start and wouldn't run very efficiently, he said.