A little while ago, I visited the BFI Canada landfill in Lachenaie (Terrebonne). It’s the biggest active landfill in Quebec, taking in non-hazardous solid waste from the cities of Laval and Montreal, as well as several other municipalities.

As I stared out my bus window at a bulldozer pushing a mound of garbage, I thought: every granola bar wrapper, every piece of Styrofoam packaging, and every item that I throw into my garbage can ends up here, crushed and buried. It sits here, forever.

BFI regularly welcomes school groups and other visitors. They are met by André Chulak, who begins the tour by discussing the importance of waste reduction, reuse, recycling and composting. Because despite some progress in these areas, the garbage just keeps on coming. Laval alone sends about 140,000 tons of garbage to landfill each year.

Most of the site was surprisingly clean, not even smelly. But as our bus rolled across two kilometres of small hills, Chulak reminded us, “Under those hills, that’s all garbage. It can go up to 12 metres deep and 40 metres high.” Between 500 and 700 trucks dump their loads each day. At the current rate, the Lachenaie site will be full in about 15 years.

As soon as a truck dumps a load of garbage, a 50-tonne compacter crushes it; when the garbage reaches 3 metres high, it is covered with a layer of dirt and a fluffy material made from recycled (non metal) car parts. Once it reaches 40 metres high, it’s topped with 3 metres of clay.

What’s leachate?

The garbage sits in cells built like vaults in clay. Beneath these cells, 10 metres of clay serve as an impermeable barrier. At the bottom of each cell, a network of drains and pipes collects the leachate, the garbage soup that leaks through when it rains or snows. The leachate decants in a system of lagoons and undergoes a biological treatment process to break down the organic matter. The water is then tested to ensure that it meets government norms on water quality. Finally, it goes to the local wastewater treatment plant.

Chulak stressed the importance of not throwing household hazardous waste (HHW) such as batteries, compact fluorescent lights, paint or medicine in with your regular garbage. “With the wind and snow and transfer process, some matter inevitably gets into the environment,” he explained. He added that municipal wastewater treatment plants are not equipped to treat such products either. (To find out where you can bring your HHW, visit the city of Laval website: Environment, Collections and Debris Sites, HHW.)

Garbage also produces biogas (resulting from the breakdown of organic matter in the absence of oxygen), composed mainly of methane and carbon dioxide. This is captured through a system of 500 wells. About 20% of the biogas goes to the site’s power plant, where it is transformed into electricity for over 2,000 homes in nearby Terrebonne and Mascouche. The rest is burned. It turns into water vapour and carbon dioxide which, in terms of greenhouse gases, pollutes about 20 times less than methane. BFI also has plans to convert the remaining biogas into natural gas.

Studying alternatives

Watching the bulldozers push the garbage around, it’s easy to make out flattened juice cartons, bits of metal or plastic. “I’d say that 75% of what ends up here could have been composted or recycled,” said Chulak. “Once it’s in the garbage truck, it’s too late.”

Many people think the garbage will eventually disappear, he said. That’s false. Glass, metal and plastic may degrade over time (a very long time), but they never disappear. “Once the hole is full, it’s full forever. All we can do is cover it up and build a park or golf course on top of it.”

Through increased recycling and composting, the city of Laval hopes to reduce the amount of waste it sends to landfill to 100,000 tons by 2017. Laval also intends to study other options, such as mechanical biological treatment or thermal treatment (incineration or gasification). Visit the city of Laval’s website (Environment section) for a report on last fall’s public consultation on its 2012-2017 Residual Materials Management Plan (in French only) and the resulting recommendations.

Yet it’s not just up to the city: it’s up to us. We can each do our part by trying to reduce, reuse, recycle, and compost when possible.