The Pine River Gas Plant, located about 45 kilometres west of Chetwynd, has temporarily halted operations after an unknown amount of amine was released in the vicinity of the plant Nov. 26.
The amine release occurred a little over a week after the plant accidentally released small amounts of hydrogen sulfide (H2S).
About 55 employees were on site at the time of the incident, and none were harmed. According to spokesperson Jenn Thomlinson, the amine release came form one of the plant's process tanks which removes any impurities from the natural gas before it makes it's way to the market.
It is not clear when the plant will reopen. The National Energy Board (NEB) plans to inspect the plant early next week.
"Clearly, under this new world of transparency and reporting, we all want to make sure that the plant is safe before we start up again," Spectra Energy's Vice President of External Affairs, Gary Weilinger told the Alaska Highway News.
The company immediately shut down the plant at the time of the incident. An inspection order issued Nov. 27 by the NEB ensures that it will not restart without its approval.
"We mustered the team on site, shut down the facility and took the appropriate measures to make sure that people were safe," Weilinger added.
At the time of the shutdown, the plant was producing about 150 million cubic feet per day of natural gas, well below its capacity of 560 million cubic feet per day because of a general downturn in the industry.
Spectra Energy's facilities in B.C. have a combined natural gas processing capacity of about 3 billion cubic feet per day.
Amine, the vapour that was released, is used to remove impurities in the processing of natural gas and is not toxic like hydrogen sulfide (H2S). However, it is a corrosive and can irritate skin, eyes and lungs.
H2S was released from the same plant on Nov. 17.
On the day of the amine release which prompted the shutdown, ambient air monitors at the plant picked up a large spike in H2S gas that neither the company, nor the NEB could explain.
Readings from the plant's air monitor showed up to 14.2 parts per billion (PPB) of H2S in the air.
Spectra could not confirm a connection between the amine release and the spike of H2S in the ambient air picked up by the plant's monitor. The government website which published the data warns that it is preliminary and has not been reviewed.
Weilinger said that the amine came from the plant itself, after an uncontrolled substance "came in from production facilities downstream from the plant," causing it to shutdown.
"We are currently undertaking an investigation to better understand the factors that led to the incident," Spectra said in an emailed statement. "At this time, we do not have any reason to believe that the Nov. 17 and Nov. 26 incidents are related."
Spectra Energy crews from Charlie Lake and other parts of the province have been dispatched to the plant to investigate.
"We've been in contact continually with the NEB inspector," Weilinger said. "We will be working to access the root cause of that release."
Weilinger said he learned Friday morning that the National Energy Board "did not intend to send someone physically to the site."
However, it was later confirmed that three inspection staff including the NEB's Chief Safety Officer will be performing inspections early next week to gather "information on the causes that led to the incident," Director of Public Affairs and Media Relations Craig Loewen said in an email.
"Presumably they are as interested as we are in ensuring that we've addressed the root cause," Weilinger added.
Spectra Energy is required to send an event summary to the NEB that details the causes and the actions it has taken to correct the issue.
The amine release is considered a low level threat by the company, not enough to set off the emergency horns in the surrounding communities of Hasler and Stone Creek.
However, it occurred on the same day that the plant tests its alarm horns—the last Thursday of every month.
Editors note: A previous version of this article stated: "Weilinger said that the amine did not come from the plant itself, but from a production facility downstream to the plant." This has been changed to show Weilinger was referring to a substance which came in from a production facility downstream from the plant which cause it to shut down. Additional information about where the amine release happened was also added to the story. The sentence "Anything over 10 PPB is considered harmful" was also removed for accuracy. The WorkSafe BC occupational exposure limit for H2S is 10 parts per million (ppm).