A third leak recently discovered on Apache Canada’s property near Zama City in northwestern Alberta has released an estimated 1.8 million litres of wastewater onto 5 hectares of land, according to the Alberta Energy Regulator (AER).
The spill was discovered on Friday, October 25th after an operator investigated a volume discrepancy at Apache’s Shekilie site, reports the Northern Journal. The leak is believed to have begun on October 3rd, according to Apache.
The released water is a waste product of Apache’s oil and gas operations in the area. Apache characterizes its operations near Zama as using “a novel enhanced oil recovery method to produce oil from what were once thought to be exhausted wells.”
Reports of the release came just one week after Apache announced it had discerned the cause of a much larger incident that occurred in June, spilling 15.4 million litres of produced water in a 42-hectare area.
Images of the June spill, released by the Dene Tha to Nathan Vanderklippe, show the high-oil content of the release. According to the AER (formerly the ERCB) roughly 2000 litres of oil were released in the originally estimated 9.5 million gallon spill.
The spill, caused by a pipeline failure, released produced water into the surrounding forest for nearly one month – May 5th to June 1st – before it was detected. According to Apache, “the failure of the less than five-year-old pipeline was caused by stress corrosion cracking.”
“Apache believes a pinhole in the exterior plastic liner allowed water to leak into the pipe, which mixed with sulphur gas, causing stress corrosion cracking and the sudden failure of the pipe.”
Apache initially reported only 9.5 million litres were spilled, due to “volumes…incorrectly allocated to another injection well.”
A third and much smaller spill was also detected earlier this year.
According to the AER, the cause of the most recent spill remains unknown, although the pipeline “is shut in a depressurized.” Both the AER and Alberta’s Environment and Sustainable Resource Development are present at the site.
The AER reports there are impacts to vegetation although no impacts to water bodies or wildlife have been reported. As of October 31st more than 600,000 litres of the spilled waste water had been recovered, reports the AER.