Calgary-based electricity producer TransAlta Corp. is suing the Alberta government and the Alberta Energy Regulator to prevent oil and gas companies from fracking near the largest hydroelectric power plant in the province, because the technique could cause earthquakes.
The lawsuit, which was filed in Alberta’s King’s Bench District Court in September, comes as two oil and gas companies filed for fracking within three miles of the dam.
TransAlta is concerned about possible seismicity causing damage to the Brazeau power plant, near Drayton Valley in central Alberta, as well as loss of wildlife, habitats and life.
The company points to an agreement from the 1960s, when the Brazeau Hydroelectric Dam was built, which states that TransAlta must “peacefully enjoy and own the property” without any “interruption or disruption to the province or any other person.” “.
TransAlta also references a section of the Brazeau agreement, which states that the provincial government had agreed not to allow oil patching activities that would restrict or hinder the power plant.
In court documents, the company said the province “has not developed, implemented or issued clear policies that will protect Brazeau Storage and Power Development from “unacceptable” risks of hydraulic fracturing in close proximity.”
The case highlights a growing debate in the scientific community about the risk of earthquakes due to fracking.
Fracking is a commonly used technique in the oil patch. When drilling an oil or natural gas well, a high-pressure mixture of water, sand and chemicals is injected into an underground rock formation to create cracks and access the hydrocarbons. The injection of those liquids can cause earthquakes.
There are thousands of documented cases of fracking activity causing earthquakes in North America, including Alberta and British Columbia.
Restrictions near Brazeau Dam
The Brazeau power plant is located about 200 kilometers southwest of Edmonton.
Fracking is currently not allowed within a three-kilometer radius of the plant. However, the Alberta Energy Regulator (AER) permits fracking between two and three miles in certain cases based on several factors, such as an assessment of risk, the potential for seismic events and mitigation measures.
West Brick Energy Ltd. and Ridgeback Resources Inc. both want to fracking in the three to five kilometer zone. A 10-day hearing is scheduled for the first half of 2023.
A 2016 technical report from a government commission stated that there was “an unacceptable risk associated with hydraulic fracture-induced seismicity to the … Brazeau infrastructure within the five-kilometer buffer zone.”
However, a follow-up report in 2021 stated that “action to reduce risk is clearly necessary if the risk is unacceptable, which does not appear to be the case.”
TransAlta wants the court to intervene and, among other things, prohibit fracking at the dam.
“As we prioritize the safety of all our facilities, TransAlta is taking this cautious step to reaffirm the government’s contractual obligations not to limit or disrupt the safe operation of the facility,” the company said in an email. .
In its defence, filed in September, the provincial government argues that the court should dismiss the case, including to avoid encroaching on AER’s jurisdiction as regulator of all oil and gas activities in the province.
In court documents, government attorneys say that “there is a lot of discussion among interested stakeholders about the risks of hydraulic fracturing in the three-mile area,” including some saying fracking is “dangerous,” while others saying fracking is “zero, or nearly zero.” risk if performed within specific shallow geological formations.”
The government made no comment to News. Westbrick Energy and Ridgeback Resources did not respond to interview requests.
Ongoing scientific research
There is no doubt in the scientific community that fracking can trigger earthquakes, but researchers cannot accurately predict when a major earthquake will occur.
Statistics show that only a small amount of fracking activity will actually trigger a noticeable earthquake, so researchers are focusing on trying to figure out why, said Honn Kao, a senior seismology researcher with the Geological Survey of Canada.
Without knowing whether an earthquake will occur, experts will instead create a risk model to calculate its probability.
“Then the debate starts. The probability is a lot like the weather, right? You say there is a 50 percent chance of rain. What do you mean? For an operator and the local community, if there is an earthquake, it is 100 per cent . If there is no earthquake, it will be zero,” Kao said in an interview.
“But from a scientific point of view, we say, well, there’s a 50 percent chance. That’s actually subject to interpretation, and I think a lot of discussion comes out of that.”
Induced earthquakes are felt most strongly at the oil well drilling site and then slowly decrease in strength as the distance is further away.
The earthquakes are caused by a buildup of stress on tectonic plates from fracking activity, although scientists can’t measure how much tectonic energy has accumulated and how close the plates are to failure. Fracking also acts as a trigger for the earthquake.
At some point, regulators have to make a decision about safety standards and determine their level of risk tolerance, but others in the community will disagree. This disagreement is central to TransAlta’s legal action over how close fracking can occur to the hydroelectric plant.
“To what extent do you want to set up that exclusive zone? That’s actually up for discussion,” Kao said. “How high or how low of a risk tolerance level can you accept?
“We know a lot more about injection-induced earthquakes in the past decade, but I definitely think we still have a lot to learn,” he said.
AER subject to separate legal proceedings
In a separate case, TransAlta is also filing a lawsuit against the AER for approving an oil and gas company’s request to “immediately” break between three and ten kilometers of the dam, “depriving TransAlta of the opportunity to build a to submit a statement of concern to the AER.”
The company is asking the courts to express its security concerns over the proposed fracking activity to the regulator.
The AER said it would not comment on an active legal matter, but it did refer to information about its rules for fracking near the Brazeau dam. The regulator has 50 seismic monitoring systems across the province.
Some of the largest earthquakes caused by fracking in western Canada are a 4.5 event on the Richter scale near Fort St. John in northeastern British Columbia. In the Fox Creek area of Alberta, there are two magnitude 4.4 earthquakes and one magnitude 4.8 event.
An earthquake of more than 4.0 magnitude occurred in the Brazeau dam area in 2019. The epicenter was about 75 kilometers south of the power plant.
The number of earthquakes has rose quickly in Texas, Oklahoma and other parts of the United States with oil and gas production. As a result, the number of lawsuits against the industry has also increased significantly.