It’s been blamed for contaminated well water, unsightly well pads and even earthquakes. But hydraulic fracturing, or fracking, is a safe and well-regulated process that’s been used for decades, says the president of the Canadian Society for Unconventional Resources.
Mike Dawson shared his perspective on Tuesday during the 2011 Synergy Alberta conference in Red Deer. He said fracking — the process of fracturing rock formations with high-pressure fluids to allow natural gas and oil molecules to flow out — jumped into the public eye in recent years and is often referred to as a “new” technique.
“Hydraulic fracturing is not a new process,” he said, pointing out that it’s been utilized for nearly 60 years.
What’s changed, he said, is the way it’s now incorporated with drilling. This includes long horizontal wellbores along which dozens of fracs can occur.
As a result, said Dawson, oil and gas reserves in tight rock formations that could not previously be extracted economically are now accessible.
A common concern expressed about fracking is the potential for oil and gas to subsequently leak into groundwater.
“There have been some unfortunate incidents, no question about it, where companies have done poor well construction to isolate those shallow groundwater horizons from what they’re doing deeper down,” said Dawson.
“It is not a hydraulic fracturing issue. It’s proper well construction.”
If the wellbore is sealed properly, oil and gas molecules cannot reach groundwater supplies, he insisted.
“There are enough impermeable barriers through that 2,000, 3,000 metres of strata that are not going to allow the migration of hydrocarbons vertically.”
The surface footprint at a production site can be significant, with pumper trucks, storage tanks and a variety of other equipment, said Dawson. But the typical practice is to drill multiple horizontal wellbores from a single pad, resulting in a much smaller disruption than would be the case with the dozens of vertical wells required to access the same area.
He also argued that regulators like the Energy Resources Conservation Board have kept pace with the technology.
Asked about the volume of water required for the fracking process, Dawson said the number varies with the situation. A shale gas well with 18 to 20 fracking stages might require one million to two million gallons (4.5 million to nine million litres), he said, with about 40 per cent of this recoverable.
As for the risk of fracking-induced tremors, Dawson said drilling companies have detailed seismic maps that allow them to avoid geological faults.
hrichards@www.reddeeradvocate.com