Imperial Oil is working on the best way to reclaim well sites that are on sensitive wetlands at Cold Lake.
Over the last decade, more than 800,000 native trees and shrubs — white spruce, aspen, Jack pine, birch, willow, alder, dogwood and pin cherry — have been planted at Imperial Oil’s Cold Lake operation, the world’s largest in situ oil sands operation.
So far, the company has reclaimed nearly 70 per cent of the lands that have been disturbed at the operation — mainly roadways, pipelines and utility corridors.
Restoring wetlands is an important focus of
conservation efforts at Imperial's Cold Lake operation.
Now, Imperial Oil is working on the best way to reclaim well sites that are on sensitive wetlands at Cold Lake. To recover underground oil sands deposits, the in situ operation has more than 4,000 active wells drilled from 200 multi-well pads, many of which are on wetlands with diverse vegetation and wildlife.
The company has been monitoring the wetlands for years, evaluating different plant species and using shallow wells to measure water levels. Starting in 2008, Imperial Oil and Ducks Unlimited Canada (DUC) teamed up on a pilot project to explore the best way to restore a wetland.
The project — conducted at a well pad on a wetland — could lead to a new industry standard for reclamation. Rick Shewchuk, development manager and former head of wetland protection and restoration for DUC’s Western Boreal Program, says the wetlands in and around the Cold Lake area consist mainly of bogs, fens and water-saturated peat, as opposed to open bodies of water. “In this highly interconnected watershed, these wetlands are key to maintaining water quantity and quality throughout for all waterfowl, wildlife and fish species in the system,” says Shewchuk.
“A well pad is akin to constructing an island on the wetland,” says Jennifer Haverhals, Imperial’s environmental team leader at Cold Lake. A clay cap and geotextile liner are laid over the wetland to protect its seeds before the well pad is built. “We want to see if we can remove or partially remove these clay islands in a way that maintains the proper drainage across the site and allows natural vegetation and wildlife habitat to return,” Haverhals says.
So far, so good. The liner was removed over the winter and natural revegetation was observed over the following summer. That observation will continue for several years.
“When you remove a bog or a fen that’s developed over thousands of years, you cannot expect it to come back quickly,” says Shewchuk. “So you are probably looking at changing the matrix and functions of wetlands, and there’s a lot left to be learned about how to do that.”
Restoring wetlands is a complex, long-term challenge for energy companies. The oil sands lie within the western boreal forest, which contains one of the highest density of wetlands in Canada.
Shewchuk says the pilot project with Imperial Oil could have big implications for reclamation efforts. “Companies are being more proactive about looking for science-based solutions to make their operations more acceptable,” he says. “There seems to be a higher level of interest and spirit of co-operation to find reasonable solutions for all interests.”