Composting: an intricate tale of rot

By Rhiannon Kirkland

It’s lunchtime in MacHall and hundreds of students are eating. When they are done, they will dump their leftover food into the garbage. From there it will go to the dump. As this process repeats itself day after day, meal after meal, thousands of tonnes of organic food waste ends up in landfills, but it doesn’t have to- it could be composted.

The City of Calgary doesn’t offer a curbside organics collection program. It does, however, offer seasonal composting programs for leaves and pumpkins during the fall and for Christmas trees during the winter. This year, Christmas tree collection was offered both by depot and curbside pickup. Christmas trees are brought to composting facilities at city landfills, said Paula Magdich, program development leader with City of Calgary Waste and Recycling Services.

“With the Christmas trees, we did see about an 11 per cent increase over last year, so it’s hard to say, but you can make that assumption that it does make it easier for folks,” said Magdich.

The City of Calgary also subsidizes backyard composters which can be purchased through the Green Calgary Association for about $25. The association offers workshops on how to use a backyard composter for those who want to start but don’t know how, said Magdich.

Backyard composters work throughout the year, even during the winter, said Pat Smith-Allen from Worms at Work, a Calgary-based vermicomposting company.

“If you don’t really know what you’re doing, then you may not get the results you want to see,” said Magdich. “You just have to make sure that you balance the material that you put in, that you turn it regularly and, especially in Calgary where it’s so dry, you have to make sure there’s enough moisture, so you have to add water to it and get it going.”

Interest in composting in Calgary has grown recently. Green Calgary sold 1,000 backyard composters in 2006 and jumped to 2,200 in 2008, said Sarah Begg, Green Calgary Commercial Environmental Services manager.

“Interest has definitely increased since the City of Calgary Blue Cart program started. People are more aware of their waste and organic waste is more obvious than ever, so composting is a great solution,” said Magdich.

Vermicomposting, or composting with worms, is one option available in Calgary. According to Smith-Allen, all you need to get started with vermicomposting is plastic storage bins and worms.

“If you look after the worms, you never have to buy them again,” said Smith-Allen. “The advantage of worm composting is that you can do it all year round. You can do it in an apartment or a condo, you don’t have to have a house to do this.”

Most people start with either a $35 half-pound of worms or a full-pound of worms, depending on how many fruit and vegetables they want to compost. It takes about four to five months for the composting process to be completed, said Smith-Allen.

“In 2004–2005, there was a one year pilot project where we [the City of Calgary] did curbside collection of recyclables and organics from about a thousand or so homes and it was very successful, but at that time after the pilot went to Council, the direction that we received was for now to focus on the recycling component,” said Magdich.

The City of Edmonton began its composting program in 2000 with a large indoor composting facility for both municipal solid waste and sewage bio-solids. Organics and garbage are collected together from residents’ houses and then sorted. Garbage goes to the dump and organics are composted, said Garry Spotowski, who coordinates education programs for City of Edmonton Waste Management.

The Edmonton program currently only serves households. They hope to expand the program to serve businesses soon with the construction of a new composting facility, said Spotowski. Residents pay a monthly fee for all their waste management services.

Toronto employs a similar program where organics and garbage are collected separately, said Pat Barrett, a City of Toronto spokesperson. Toronto started the program to divert waste from landfills.

Most cities use slightly different collection and processing methods, which affects the program cost.

“People want to do the right thing but ultimately it should be easy and it should be convenient,” said Barrett.

Curbside programs tend to be more expensive than depot, backyard or vermicomposting.

“Disadvantages would be the added transportation and associated greenhouse gases produced to drive around and pick up the compost. Also, individuals would not be able to benefit from the finished compost product for their gardens,” said Magdich.

It can also be difficult to locate composting facilities due to odour concerns. The Edmonton facility was designed to have special odour control measures like biofilters and negative air pressure to ensure nearby residential areas wouldn’t be affected, said Spotowski.

“They are contained within buildings. To look at the structure, I’m sure you wouldn’t think that it is any different than any other small business or manufacturing building. The smell is inside the building and the digester tank is fully enclosed,” said Barrett.

One of the advantages of backyard and vermicomposting is that residents get to keep their compost and use it. There is less individual effort involved in curbside programs, but residents have less access to the final product.

“[Composters] feel good about it and it’s kind of ingrained in their routine. They can produce compost when they want it right on their own property, therefore it can be available whenever they want to use it,” said Laurie Lewis, Diversion Planning coordinator with the City of Halifax.

Cities like Edmonton and Toronto that have curbside organics programs sell compost or give it back to residents.

In landfills, all the nutrients in organic waste are lost and can’t be used for soil reclamation or gardening.

“There’s more of a demand for it than we can even fulfill. It’s used for turf management by landscapers, for erosion control in agriculture and some is marketed to residential gardeners,” said Spotowski. “It took a while to build those markets up, but once they’ve been established, they’re very strong.”

Organics make up about 30 per cent of household waste, so composting allows for a great deal of diversion from landfills. Having less material going into landfills

means they last longer.

“Ironically, it’s biodegradable materials that can cause some of the problems in a landfill,” said Spotowski. “When organic waste like grass clipping et cetera are poured into a landfill by the tonne and then covered up with dirt as they are, they decompose in the absence of oxygen and that creates something called landfill gas, which is half methane and half carbon dioxide, both important greenhouse gases.”

The University of Calgary has two sets of organic collections programs. The first is for kitchens and the second is for post-consumer food. The kitchen program has organics placed into separate bins that are taken to East Calgary Composting. Staff and students can place leftover food into organic waste bins located near food services in MacEwan Student Centre, ICT, Education and elsewhere, said Doug Wilson from U of C Facilities Management.

“Right now, in MacEwan Student Centre we’ve got a compost bin set up so if you didn’t eat all of your lunch, you can go to that compost bin and scrape your plate in there and throw your Styrofoam plate or whatever it is in the garbage,” said Wilson.

The post-consumer food is then composted on campus in a sealed vessel composter. The program started near the end of 2009 and will hopefully be expanded outside in the next 18 months, said Wilson.

Spotowski thinks we are in a second wave of waste diversion and environmental consciousness. The first wave took place during the late 1980s and early 1990s due to concerns about acid rain and other environmental issues.

“That’s when recycling programs really began to be introduced throughout North America,” said Spotowski. “People saw the amount of say, newspapers and tin cans they were throwing out that could easily be recycled and that was sort of the start.”

According to Spotowski, the second stage of waste diversion that most cities develop is an organics collection program. Recycling only diverts about 20 per cent of residential waste while organics usually comprise a majority.

“Recycling is a kind of doorway, you might say, towards other waste diversion programs,” said Spotowski. “It’s something that people can relate to very easily and very quickly and once they begin that, they begin to look at other ways they can really deal with their waste.”

Spotowski says that programs exist in hundreds of cities throughout North America and the world and have changed the way people perceive waste.

In school, students are taught about the three Rs- reduce, reuse and recycle- but recycling gets the most attention.

Recycling is often promoted first because people can see the results.

“If you reduce, it’s not generated at all, and then you don’t have to find something to do with it,” said Begg. “We definitely promote reduce and reuse as much as possible, from hav[ing] little to no packaging on the products we sell in our EcoStore to discussing smart shopping habits ­- buy in bulk, buy quality products that won’t break, ask yourself if you really need this item or if you have something at home already that will work just as well.”

Recently there has been a trend towards reusable groceries bags, coffee mugs and other products focused on reducing and reusing. Recycling is still a good idea and for some in Calgary, composting is the next step.

“We’re trying to raise the consciousness, that you think a little bit more about what you generate as a household. You know what your footprint is on this earth beyond, ‘I’m going to put something at the end of my driveway and I don’t care what happens to it, just get it out of my sight,’ ” said Barrett.

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