The City of Calgary's brand new Green Cart composting facility — the largest of its kind in Canada — is on schedule to open by the summer.
"We have over 200 workers onsite putting the finishing touches on the facility over the past few months," reports senior project engineer Sarah Smith. "Construction is on track and the facility will be ready in time for the city's first Green Cart collection day this summer."
Work began on the composting project in the fall of 2015. Smith notes that Calgary City Council approved a capital budget of $143 million for the three buildings that make up the complex which is located on the Shepard Waste Management Facility south of 114th Avenue S.E.
"City council decided on a P3 (public-private partnership) arrangement for the project," Smith says.
Chinook Resource Management General Partnership (CRMG) was selected to design, build and operate the facility. CRMG is a consortium led jointly by Bird Construction and the Maple Reinders Group and comprised of Maple PPP and Bird Capital as developers, Nason Contracting Group, a wholly owned subsidiary to Bird Construction, Maple Reinders Inc. as design-build contractors, AIM Environmental Group as operations and maintenance provider for a 10-year term, and Stantec as design and permitting liaison.
The complex will consist of a main building, curing building and storage building. Together, the facility is 521,000 square feet. The facility is expected to be able to process up to 145,500 metric tonnes of both residential food and yard waste and dewatered biosolids from the city's wastewater treatment process, in all producing two different compost varieties every year.
"The facility will process food and yard waste year-round and biosolids from our wastewater treatment plant in the winters," Smith says. "That allows us to operate at full capacity year round. We understand how important it is to be a good neighbour to the communities and businesses around us. Traffic will be kept away from residential areas, and enter and exit just as landfill traffic does now. The facility will use and comply with environmental regulations."
Natural design features like trees and embankments will also help the facility blend in with the surrounding area. An extension to the regional pathway system has been built outside the eastern edge of the site. A new stormwater pond, which looks like a natural wetland, is also being built.
The facility will be using the most advanced air filtration technology, Smith notes. A major piece of the project, she says, is the odour control portion.
"We've invested in odour control systems to filter them out. Large biofilters are used to reduce odours before exhausting air from the building. Air from both the active composting and curing phases is directed through the biofilters," she explains.
The waste material is loaded into 18 composting vessels. The material stays in the composting vessels for 21 days. The vessels are monitored for things such as temperature, moisture content and oxygen levels. This keeps the decomposition process running smoothly. The curing requires another 21 days, after which the nutrient-rich finished product is ready.
"The facility will produce high quality compost," Smith says. "The scenario is that it won't be the city itself that is selling the composted material. Arrangements have been made for an independent operator to sell the material."
The majority of the finished compost will be sold in bulk to companies such as landscape soil blenders and compost baggers. The proceeds from the sale of the compost help reduce the processing cost and lower the Green Cart program fee.
A portion of the finished compost will be made available to the community for free. This includes being made available for community gardens and through select giveaway days to the public. Compost will be available beginning in 2018.