By Doug Hallett
While the city’s new composting plant ramps up towards full-capacity testing, city hall is also eyeing the possibility of residents being allowed to line their green bins with compostable plastic bags.
“We need to demonstrate we can deal with 30,000 tonnes (of organic waste) a year without producing odour,” Dean Wyman, the city’s general manager of solid waste resources, said of the testing going on at the organics plant.
To do this, the tonnage of wet waste being processed at the composting plant has been ramped up this summer, using organic waste from Guelph, Waterloo Region and Hamilton, to test how the plant operates at full capacity. This “substantial completion phase” should be finished by the end of August, Wyman said in an interview.
Maple Reinders Constructors Ltd., which built the plant, needs to demonstrate that the facility can be operated as the city originally requested, Wyman said. If the final testing this summer is successful, the city will be able to “sign off” and take ownership of the facility from Maple Reinders.One-third of Guelph households are to go on the new three-bin system this fall, and the city has been fine-tuning preparations.
One question that city hall has been getting is why residents can’t use biodegradable plastic bags to line their green bins, since Peel Region and several other Ontario municipalities on the bin system let their residents do this, Wyman said.
In response, city hall is getting ready to ask the provincial Ministry of the Environment to amend its certificate of approval for Guelph’s composting plant to allow use of compostable bags for lining green bins, he said.
First, though, it is consulting with the composting plant’s public liaison committee, which includes residents living near the plant. The committee discussed the compostable plastic issue at its most recent meeting.
The committee members have asked to “provide their comments or suggestions or concerns to the city by Aug. 24,” Wyman said.
Then, he said, “we will address those concerns to the best of our ability before we apply to the ministry for the amendment . . . probably in the early fall.”
Last year, a provincial tribunal struck down an MOE order banning plastic from a composting facility in Ottawa. However, the Ottawa plant is located in an industrial area, not near homes as Guelph’s plant is, city council was told in December.
The non-compostable bags currently used in Guelph have been linked to odour problems, as “anaerobic” digestion by microbes can happen in the absence of oxygen in plastic bags and cause odours.
However, Wyman said he doesn’t see this as a problem if compostable bags are used to line green bins in Guelph.
For one thing, he said, “we don’t have any odour issues since we modified the plant” earlier this year.
“So I don’t see odour being an issue” if biodegradable plastic bags are allowed to be used as green bin liners, he said.
It stands to reason that people using compostable bags as liners wouldn’t close them up until just before they’re put out to the curb, so there wouldn’t be much time for anaerobic digestion to occur, he said. As well, wet waste is “quickly debagged” after it’s collected at curbside.
An amendment to the plant’s MOE certificate of approval permitting compostable bags might also bring more revenue into the composting plant, Wyman said.
Guelph currently generates only about one-third of the 30,000 tonnes of organic waste the new plant is capable of processing in a year, so wet waste from elsewhere is needed to fully use its capacity.
A deal the city signed in 2010 with the Region of Waterloo to take 20,000 tonnes a year of its wet waste to process in the Guelph plant doesn’t start until October 2013. So there’s time before then to earn revenue by taking wet waste from other municipalities, especially if compostable plastic is allowed, Wyman said.
He said Waterloo Region isn’t generating as much wet waste as was expected, which is why some organic material is coming from Hamilton for the full-capacity testing of the Guelph composting plant this summer.
Aim Environmental Group, which has a contract to process Waterloo Region’s waste, operates similar composting plants in Guelph and Hamilton and is able to shift material around.
Waterloo Region is “contractually obliged” to pay for processing of 20,000 tonnes of wet waste annually in the Guelph facility after October 2013, Wyman said, and “if they don’t send us 20,000 tonnes a year, they still have to pay us as if they did.”
If Waterloo Region sends less than 20,000 tonnes after the contract starts next year, Guelph might even be in a position to process some wet waste from other municipalities and in effect be paid twice for the same processing space, he said.
The deal with Waterloo Region runs from 2013 to 2023, with options of two five-year extensions. It calls for Waterloo Region to pay Guelph $117 a tonne in 2013, with the price adjusted upwards at the rate of inflation for 10 years.
Waterloo Region, which encourages but doesn’t require residents to use their green bins, doesn’t allow plastic of any sort in its green bins.
Up to now, Guelph has insisted it wouldn’t allow plastic in the green carts.
In a recent Tribune story, a city spokesperson said green bins should be lined with “newspapers, shredded paper, flour or sugar bags, or cereal boxes.”