They say if you hold onto your old clothes long enough, one day they’ll be back in fashion. The same can be said for some concepts in composting.
Recently I was asked to give a mini Master Composter course, in Stratford Ontario, as a kick off to a backyard composting program starting this summer in some apartment buildings. When I started in this industry years ago I helped teach some Master Composter classes, in the course of which I made use of the Recycling Council of Ontario’s 1995 Master Composter Guide.
I came across the document recently and found it to still be quite relevant.
Backyard composting was all the rage 20 years ago as many realized that organic waste is a critical part of the waste diversion solution; it was an inexpensive way to start. However, municipalities hit a “participation wall” and realized to get more off the street it needed to be collected directly from homes. That’s how it’s evolved ever since.
Some municipalities are now hitting a “cost wall.” Curbside collection and processing of organic wastes is expensive; frankly, they can’t afford it. So, after 20 years the humble backyard composter is coming back in fashion.
Considering the past is useful in setting future directions.
In that regard, Environment Canada’s recently released Technical Document on Municipal Solid Waste Organics Processing is useful. (Full disclosure: My company submitted an unsuccessful proposal to complete this work.) The document is well put together, and encapsulates the current state of knowledge for organic waste processing, a kind of one-stop-shopping guide for decision makers, government officials, facility operators and solid waste managers.
The document is a bit like the Old Testament: It starts with the genesis and current context of municipal organic waste processing, including the benefits of organic waste diversion, how the various processes work, an overview of technologies, how to use the end products, and so on.
There are extended proverbs on how to deal with the Achilles heel of odour, as well as other nuisances that take otherwise beneficial processes and make them unappealing.
It’s not that any of this information, particularly as it relates to composting, is “new” — it was just scattered in various places; the possible exception being the info on anaerobic digestion (AD), which will be less familiar to readers (and is important to include side-by-side with composting). AD, which has lurked on the fringes, is making some real in roads with the construction of new public and private sector facilities. (See article, page 18)
The guide is presented in such a way that a person planning an organic waste diversion program in their municipality can, with some time and diligence, learn what they need to know to help with planning and decision making.
This guide adeptly focuses on decision makers faced essentially with source-separated residential waste streams that make up about 14 per cent of Canada’s waste generation. It does not, however, elaborate on how to capture and process more “difficult to extract” multi-residential and IC&I waste streams. (If we ever hope to achieve 50 per cent waste or higher diversion, these waste streams need to be a fuller part of the equation. One quarter to one third of residential organic waste comes from multi-residential buildings. The IC&I waste stream is poorly quantified but makes up at least the same amount as the residential sector.)
If the current guide is the Old Testament, the New Testament will be the next document that looks into the future to determine how best to tackle these waste streams.
While source-separation programs result in the best quality end products (particularly as pertains to compost), there will be a wall where source-separation becomes impractical. As it currently stands, that wall may be single-family residential with snippets of multi-rez and IC&I wastes.
To achieve the lofty waste diversion goals we’ve set for ourselves, we’ll need to consider quantitative measures such as bans and landfill taxes to drive organic wastes to more desirable places. We should also consider more AD with effective pre-treatment, and also mechanical biological treatment (MBT), which may only have a modest hope of generating a marketable product, but which at least minimizes the impact of organics at the time of disposal.
The EC document can be downloaded here: www.compost.org/
Paul van der Werf is President of 2cg Inc. in London, Ontario. Contact Paul at firstname.lastname@example.org