5 Wing Goose Bay, a Canadian Forces base in Newfoundland and Labrador, Canada, is an important refuelling station for Canadian military planes. Over the years, however, miscellaneous releases of petroleum hydrocarbons have caused serious environmental contamination to the area’s groundwater. It was estimated that as many as 10 million litres of hydrocarbons (enough to fill four Olympic-sized swimming pools) were sitting on the water table some 30 metres underground.
In 2008, SNC-Lavalin was awarded an engineering, procurement and construction management contract to clean up part of a 5.5-hectare area of the base known as Main Gate. SNC-Lavalin’s success on its first assignment at Goose Bay set the stage for new contracts for other areas, including Heavy Bomber Hydrant, one of the most contaminated areas at 5 Wing Goose Bay. All together, SNC-Lavalin is now responsible for remediating close to 50 hectares of the base.
To recover and treat petroleum located at depths of over 30 metres, the project team developed a new and customized multi-phase hydrocarbon extraction technology. The technology creates a vacuum on the surface of the contaminated groundwater and evaporates the hydrocarbons into the vapour stream. Hydrocarbon vapours are pumped into mobile treatment facilities where they are reformed into liquid, treated and stored for disposal. Clean, treated groundwater is then pumped back into the ground. This method is more efficient than the conventional “pump and treat” method, which is more indiscriminate in what it pulls up. Because SNC-Lavalin’s method extracts less groundwater, it allows the company to reduce the scale and cost of its dewatering and treatment processes.
Since 2009, SNC-Lavalin’s extraction systems have recovered more than 1,000,000 litres of hydrocarbons from the area’s groundwater. This will have a positive impact on the local environment and safeguard the health of the people who depend on the local water table. SNC-Lavalin’s success with hydrocarbon extraction recently led the government of Canada to issue a public tender to encourage other businesses to use the same technology.