Satellite data sound alarm on safety of bitumen extraction by Jason Fekete, PostMedia News, February 3, 2014, Calgary Herald
Satellite imagery used by the federal government to review a major bitumen leak last year in Alberta has found the project’s steam-based extraction caused “measurable levels of ground deformation in the area of the leak” at a rate 10 times faster than other oilsands operations. The data obtained from satellite observations — and presented to senior officials at Natural Resources Canada last fall — are sparking new questions about the incident at a Canadian Natural Resources Limited (CNRL) operation in northeast Alberta and the safety of bitumen extraction.
The information is also sounding more alarm bells for the nearby Cold Lake First Nations, who are worried various oilsands operations in the area are contaminating local groundwater and damaging their traditional lands. Briefing materials prepared for the deputy minister of Natural Resources Canada, and obtained by Postmedia News under access-to-information legislation, show the federal government used satellite imagery from RADARSAT-2 to study the extent of ground deformation — caused by steam-based extraction — in the vicinity of a major bitumen leak in June 2013 at CNRL’s Primrose operation approximately 45 kilometres northwest of Cold Lake, Alta.
The CNRL project is a thermal in situ operation that sees high-pressure steam injected into the ground down a wellbore to reduce the viscosity of the oilsands product and allow the bitumen to be pumped to the surface (in what’s called cyclic steam stimulation). After the bitumen emulsion leak was reported by the Alberta Energy Regulator on June 24, 2013, the Canada Centre for Mapping and Earth Observation (CCMEO, which is located within Natural Resources Canada) used what are called earth observation techniques to assess the bitumen leak, and discovered subsidence and uplift of the land over several years.
“Results obtained using imagery from Canada’s RADARSAT-2 (satellite) indicate that steam-based extraction caused measurable levels of ground deformation in the area of the leak, within the 2009-2013 period,” say September 2013 briefing notes prepared for NRCan’s deputy minister, who reports to federal Natural Resources Minister Joe Oliver. The satellite data found that between 2009 and 2013, the values of ground deformation (both subsidence and uplift) at the CNRL operation were often in the range of 10-30 centimetres over various sampled 24-day periods. “Preliminary analysis also shows that the rate of ground deformation is approximately 10 times faster than changes observed by CCMEO in the Fort McMurray area, which uses the lower-pressure steam-assisted gravity drainage (SAGD) method,” say the briefing notes. “While the deformation rates observed here are high relative to the SAGD steam-based operations, we cannot at this point indicate that these are atypical of this process in this region and/or are related to the bitumen leak.”
More than one million litres of bitumen has seeped to the surface from the major leak, which still continues several months later, albeit very slowly during the winter months. There have been at least three other separate, much smaller, leaks to the surface reported at different locations in CNRL’s Primrose operations. As of Jan. 10, 69,700 tons of impacted soil and vegetation had been removed from all the leak sites. The Alberta Energy Regulator, which was informed of the satellite data and associated findings last fall, is still conducting its investigation into the major leak. The regulator is trying to determine whether the bitumen leaked through cracks in the rock above the deposit and was driven to the surface by the high-pressure steam pumped underground in the extraction process.
CNRL has since been ordered to halt its steaming operations at the site of the leaks. The company blames the major leak on a well failure and is spending $40 million to clean it up. It was ordered to drain a small lake on the Cold Lake Air Weapons Range to find a way to contain bitumen that was seeping into the water. The Alberta Energy Regulator, however, said earlier this month it doesn’t necessarily share CNRL’s view that a well failure is solely to blame, although its investigation continues. The regulator’s data show there are at least eight different cyclic steam stimulation bitumen operations throughout the Cold Lake, Athabasca and Peace River oilsands formations in northern Alberta.
The nearby Cold Lake First Nations says details about the land deformation — and it occurring at a much faster rate than other oilsands operations — have not been shared with them. Cold Lake First Nations Councillor Sally Scanie said council members have done a fly-over of the major leak but have not been allowed on the land to see it up-close. They remain worried the oilsands operations could be contaminating their ground water, and irrevocably damaging the land and future hunting. “It has always been a concern for Cold Lake First Nations,” Scanie said. “Continuous abuse of the Mother Earth is just coming to the surface now, and it could get worse. Do we anticipate it to get worse? Of course we do, and that’s why we’re raising concerns.”
A spokesperson for CNRL said the cyclic steam stimulation extraction technique has been used in the Cold Lake area for more than 30 years, with the surface deformation having been measured since the 1980s and satellite data used since the 1990s. “Canadian Natural is committed to continuous improvement. We have been using this valuable (satellite) data to effectively calibrate our models and optimize our steaming operation since 2002,” CNRL spokesperson Zoe Addington said in an email. The company is undertaking a comprehensive review to determine the cause of the bitumen flowing to the surface, she said.
To date, “all the evidence and data collected” suggest the bitumen can only leak to the surface by a failed or partially failed wellbore, she said.
Darin Barter, spokesman for the Alberta Energy Regulator, said it’s “premature” to discuss the AER’s scientific assessments of the satellite data and other information because the investigation continues. He notes, though, the AER has not deemed the incident ‘over.’ “Until the investigation is complete, we cannot speculate on regulatory changes that may or may not occur,” Barter said in an email. [Emphasis added]
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