Waste diversion, odour and climate change

Clare Booth Luce, the famous American playwright, journalist, ambassador, and Congresswoman, used to say, “no good deed goes unpunished”. To my regret, this sardonic and rather depressing phrase is, all too often, a good description of environmental laws.

One example is the management of odour issues from waste diversion. Diversion of organics from landfill is an important public policy objective, for many reasons, including:

1. Organics are an important soil fertility resource, at a time when soils are being depleted and impoverished worldwide[1];
2. organics waste scarce landfill space;
3. organics in landfills creates leachate, which can create long-lasting pollution of groundwater and nearby surface waters; and
4. organics in landfills create methane, a greenhouse gas much more powerful than carbon dioxide.
   1. Global methane emissions from landfill are estimated to be between 30 and 70 million tonnes each year. Landfills provide ideal conditions for methanogenesis, with lots of organic material and anaerobic conditions prevalent.

Programs to capture landfill gas, whether to flare or to use as an energy source, are likely inadequate to overcome these problems:

current landfill gas emissions models … significantly overestimate landfill gas control system collection efficiencies, and thus grossly underestimate uncontrolled, fugitive methane releases into the atmosphere. Given methane’s significantly higher short-term global warming potential, the prevention of fugitive methane emissions from landfills should become a near- term policy priority….

Diversion will always produce greater GHG reduction benefits, regardless of the assumptions used…

The “divert organics” philosophy, however, is being undermined by policies and regulations currently in place… The end result is conflicting compliance issues. [2]

One such compliance issue is an excessively punitive approach to odour from composting sites. Municipalities prosecuted for such odours include the cities of Toronto, Orangeville, Sault Ste. Marie, and Guelph, and the regional municipality of Niagara. Private organics management facilities have also been prosecuted. Amaizeingly Green Products GP was fined $300,000, for seven days of odour; Maple Leaf Foods was fined $450,000. Oakridge Terra and Courtice Auto Wreckers were each fined $25,000 for odours from their composting sites.

Odours are notoriously hard to manage, and to regulate. For one thing, there is a huge range of human sensitivity to odours, so that someone may complain bitterly about scents that no one else can detect. For another, the response to odours is very subjective, and is strongly affected by factors outside the control of the odour source, including the weather, and the mental, physical and emotional status of the person smelling the odours.

As Justice Ferguson said in Pyke v. Tri-Gro,[3]

The .. human nose is a very sensitive and a very subjective instrument…. The establishment of effective odour control measures is complicated by the … absence of a direct relationship between the concentration and perceived intensity of odours for humans. … a considerable reduction in concentration of the odour-producing chemical(s) may be required … to provide a recognizable change in perceived odour intensity.

Both regulators and regulated communities would like to have some objective way of measuring how much odour is too much. Thus, we are starting to see limits, such as “one odour unit”, appearing in permits of controversial facilities. This presents compost operators with two huge problems. First, due to the many complexities of collecting, handling and composting organics, “1 odour unit” limits probably cannot be achieved all the time. (One odour unit is often below ambient.)

Second, odour units sound more scientific than they are. According to the British Columbia Environmental Appeal Board, “odour units” are not reliable enough to be legally enforceable.

In West Coast Reduction Ltd. v. Greater Vancouver (Regional District) , the GVRD imposed odour unit limits on a rendering plant. (Rendering plants provide an essential public service, but they inevitably have some odours.) The company appealed, and called expert evidence about the subjectivity and unreliability of odour unit measurements.

The Board agreed:

“… the use of odour units in this [permit] is not reasonable and appropriate. The notion that odour units can be used as an indicator of an environmental “smell” is simply too flawed to be used as a method of determining compliance, and is therefore not suitable for determining whether the environment is adequately protected…

339 [B]ias and subjectivity are present at many stages during the capture and analysis process…

345 Given that there are many steps in the process of attempting to calculate odour units which are problematic, and which contain so many points of bias and subjectivity, the Panel finds that the ultimate number or value coming out of an odour unit measurement cannot be relied upon as meaningful, particularly for the purposes of evaluating compliance with a mandatory term of a permit.

This may be an example of “the perfect being the enemy of the good”. Neighbours need reasonable protection, and everything reasonable should be done to minimize odours. But if organic waste diversion is only permitted when it is odour free, far too much organic waste may end up in landfills, causing lasting damage to the public interest.