Silt that washed down mountain creeks throughout the Bow Valley during last year’s spring flood will be composted this spring and turned into a useable soil.
Darcy Edison, chief administrative officer of the Bow Valley Waste Management Commission, said recently silt hauled from communities and other areas throughout the valley following the flood was stockpiled at the Francis Cooke Class III Landfill. Once the pile thaws, the silt will be screened to remove rocks and then composted.
“We’re going to come up with a plan using compost we already have on-site and any other material we may have to add to it in order to make a good product,” Edison said. “We’ll run it into the screening plant in order to clean it up into one size and then we’ll take that one size and if it needs compost we can add that to it. If it needs wood chips, we can add that to it, or if it needs sand.”
Edison said landfill staff will take regular samples to establish what amendments are needed and if it is contaminated or not.
Silt taken from east Exshaw, for example, was contaminated with sewage, but Edison said the composting process would destroy any pathogens.
“We’ll test for contaminates and at the same time we’ll test to find out what nutrients we’ll need,” he said. “As we go through the pile we’ll have to test it continually because the characteristics will change based on where it came from.”
Edison said he isn’t certain of the volume of silt brought to the landfill following the flood.
“In the two months after the flood we took in roughly two years worth of material,” he said. “It came in so fast we just stockpiled it, so we won’t really know how much until after we screen it out. Then we’ll have an actual volume of what was rocks and what was actual soil.”
Once composting is complete, possibly in June depending on the weather, Edison said the landfill would have a sellable product.
“Speaking with landscapers in the past they were saying this is actually a better product to put down if you’re sodding. It retains moisture better. Normally I buy topsoil and bring it, but I won’t have to do that this year.”
Despite the addition of material in the landfill, Edison said he’s still running on a 60-year lifespan.
It has, however, meant that the landfill has moved up excavation of a new cell to accommodate the space that will be used while the silt is being composted.
