A new soil reclamation facility is proposing to make Calgary’s construction industry cleaner, and cheaper.
Calgary Aggregate Recycling’s upcoming facility will divert 90 per cent of soil that would otherwise be contained at landfills. The facility is ratcheting up activity after a recent round of provincial funding for environment-related projects.
The reclaimed soil, sand, and aggregate building material can be reused in construction projects in the city.
The company estimates this could potentially lead to big reductions in the environmental impact of Calgary’s construction industry.
“The biggest emissions reductions that come out is you’re doing 90 per cent less trucking outside of the city,” said Travis Powell, president of Calgary Aggregate Recycling.
“It works out to about a 67 per cent reduction in greenhouse gas emissions compared to the conventional truck to landfill disposal method,” he said.
The soil reclamation facility, which will be added on to their current southeast Calgary location, is expected to be fully open by July of next year.
It’s timely given an upcoming notice of motion that would place Calgary on target for a net-zero emissions by 2050.
Making previously cost prohibitive projects possible
The facility will be designed around handling what the province classifies as Tier 2 soil. Examples of places where Tier 2 soil contamination might be found include old gas stations or dry cleaners.
Another example, that most Calgary Flames fans would be familiar with, is the creosote contaminated soil in the West Village, which ultimately ended a new arena deal in that part of the city.
“That whole area is creosote-contaminated soil and this facility will be able to handle creosote-contaminated soil,” said Powell.
At the time, it was estimated that the CalgaryNext arena project would cost upwards of $1.8 billion dollars.
“The amount of soil there is probably one of the biggest reasons why it wasn’t viable. You’re displacing a mountain of soil, and it’ll fill up all of the landfills in the area,” he said.
Powell said that the traditional method of using landfills to dispose of all the soil would have required building new landfills just to store the volumes that would be produced.
Reclaiming previously unusable inner-city land also reduces urban sprawl, and increases the city’s tax base.
“So instead of having a suburb where we have to build new bus lines, and we have to extend LRT lines, this is already within our city, just wasted space right now,” he said.
How it works
The new facility will remove the contaminants off of the surfaces of sand and stone within the soil.
Powell was quick to point out that this process doesn’t eliminate contaminants. The cleaned portion of the soil is safe for reuse.
“We are rinsing off, reusing it, and then concentrating the contaminated (soil) so that it takes up about 10% of the volume that otherwise would have been taken up by the same amount of soil,” he said.
Powell said this concentrated contaminant would then be able to be placed into the same landfills as before. It’s no more dangerous in the smaller concentrated volume of soil than in the original amount.
“It’s the chemical composition which makes up the hazardous part, not the concentration for the most part,” he said.
In turn, that 90 per cent reduction in soil having to be taken to landfills outside the city is also estimated by the company to translate into less air pollution from engine emissions like CO2 and NO2.
Creates sand sustainability for construction projects
One of the unexpected benefits outcomes from doing more soil reclamation in Alberta has to do with making the world’s third-most-used resource more sustainable.
After air and water, sand is next in worldwide use – in everything from construction to electronics.
According to a 2019 report by the United Nations Environment Programme, world-wide extraction of sand is increasing past replenishment rates through natural processes. This has led to threats against marine and river ecosystems, and threatens biodiversity in these regions.
This has also led to unethical and illegal extraction of sand for use in the construction trade.
“Sand is one of the most exploited materials in the world, which I didn’t know until we started really researching this facility,” said Powell.
Among the conclusions reached by the UNEP report, recycling sand was one of the “available solutions” to creating greater sustainability on construction projects that use concrete.
Government funding sped up timeline
On Nov. 1, Emissions Reduction Alberta announced 16 projects funded with $176 million in federal and provincial cash.
“Alberta continues to show leadership by using technology in practical ways to reduce emissions
and combat climate change,” said Premier Jason Kenney in a prepared statement.
Two members of Emissions Reduction Alberta attended Conference of Parties 26. It was held in Glasgow, Scotland this year, as part of the implementation process for the UN Framework Convention on Climate Change.
Of this funding, $8.8 million is being committed by ERA towards the reclamation facility.
Powell said that this funding, out of what is an overall $17.6 million project, sped up the timeline to completion by between two and three years.
“So we would have probably been two to three years before we would have taken this facility on had we solely financed it. By getting this grant it helps us put boots on the ground sooner,” he said.