Every time one more load of asphalt or concrete rubble is trucked away from a City of Edmonton construction site, Blair Buchholtz sees another opportunity for big dollar savings, lower carbon emissions and better future roadway surfaces.
Blair, you see, supervises one of the tightest, most environmentally- and taxpayer-friendly programs that the City runs – Transportation Services’ aggregate and recycling services unit.
As he explains how the service has evolved over the years, it’s hard not to envy him and his team their jobs, because everything they do is just plain smart! To a person, they openly radiate pride in running what’s likely the best program of its kind in Canada.
Construction rubble used to be trucked to a landfill. These days it would cost $60 a metric ton to landfill, plus at least a $5/tonne haul fee – $14.3 million a year given the 220,000 metric tons of rubble we generate annually.
The genesis of the aggregate recycling service was during the years when Edmonton’s landfill was nearing capacity and we were looking afar for a replacement site – which meant high trucking costs. The solution was to recycle!
Aggregate and recycling services has built two large aggregate recycling yards, one in eastern Edmonton and one in the west.
“With two yards, we cut down considerably on the trucking costs and carbon footprint since the trucks are driving shorter distances,” says Blair.
About 90% of what’s received by the program is from City neighbourhood renewal and other projects. The rest is dumped by private contractors at no charge.
Blair’s staff use a crusher to grind the asphalt-concrete mix down to pieces that are 63 mm (about 2.5 inches) in diameter; conveyor belts carry it to stockpiles, ready for reuse in the spring.
“We just turn it around and use it again as road base when we’re building or renewing roads the following year. It’s superb material because it’s angular – it doesn’t settle much after packing – and its asphalt and concrete dust content help to bind it all together.
“That combination means when it’s finally paved over, the road surface is much less susceptible to cracking, which is one of the root causes of pothole-creation,” says Blair.
If the City had to buy new aggregate material commercially, it would pay $26/metric ton for the material and $10 to $15/metric ton to haul it from quarries or pits.
“If we had to buy commercially, we’d also be generating 6,500 long distance truckloads, so just imagine the carbon footprint at 2.5 miles per gallon fully loaded!”
Blair says the tightly integrated recycling operation is designed to operate on a cost-neutral basis.
In the end, it does the environment a huge favour… and it doesn’t cost the taxpayer a cent!
