Transforming an Oilfield Waste Land Into a Boreal Forest

Transforming a former oilfield land treatment facility into a boreal forest for the benefit of the community
Apr 20, 2018 9:00 AM ET

Tetra Tech News

Consulting Engineers of Alberta (CEA) presented Tetra Tech (EBA) with an Environmental Award of Merit at the CEA Showcase Awards Gala, an event attended by more than 500 industry leaders in February 2017. The Showcase Awards recognize excellence in consulting engineering in Alberta and throughout the world. Tetra Tech received the Environmental Award of Merit for its work with Newalta Corporation to design a closure approach for a former oilfield waste land treatment facility south of Drayton Valley, Alberta.

Tetra Tech began working with Newalta in 2009 to design a safe and cost-effective closure approach for the site where oilfield wastes were treated for more than 20 years. Initial estimates to remediate the site using traditional methods exceeded $100 million, which was unrealistic, unrepresentative of the best use of resources, and did not offer an overall benefit to society.

Tetra Tech conducted quantitative risk assessments to evaluate potential human and ecological health risks due to exposure from site residual contamination and identify the most appropriate end land use. Tetra Tech further tailored the ecological risk assessment to site conditions and potential land uses with site-specific ecological toxicity, bioaccumulation, and bioavailability testing for agronomic and boreal forest receptors. Ultimately, a boreal forest conservation area was identified as the most valuable land use, promoting sustainability and returning the land to pre-development conditions.

As part of site reclamation, Tetra Tech implemented an innovative reforestation program, which included applying leaf litter and woody debris to encourage the establishment of ecosystems and reduce weeds. This approach had not previously been used in oilfield reclamation.

The ultimate goal of the boreal forest conservation area was to provide recreational land use and activities that are accessible to area residents. The area now hosts grade five students every year as part of their environmental studies course.

During the closure program, Tetra Tech consulted with land owners, governments, and parks foundations and collaborated with Environment Canada to develop the draft Environment Canada Boreal Forest and Wetland Biological Procedures, which is now used to set site-specific environmental guidelines for future projects.