They're our dirty little forgotten secret: the city's 161 closed garbage dumps. Forty one of them are still active, spewing gases and discharging a toxic slurry into sewers and waterways. City staff say we shouldn't be worried, even while reserve funds to maintain the sites have been emptied in Rob Ford's budget juggling. Truth is, our track record isn't very good when it comes to putting these oozing mounds to bed.
Garbage science: the 1-2-3s
We used to burn the contents of most landfill sites closed before the 70s, which released dioxins and who knows what else into the atmosphere but left fewer harmful volatile organics in the ground. Good news (sort of).
Jackpots and surprises
The bad news is that landfills were terribly designed back in the day, and little thought went into their location. Worse, there were no controls on what was put in them, including hazardous waste. The province didn't start regulating landfills until the late 70s. And diversion of recyclables from dumps wasn't undertaken in any meaningful way until the 90s. Stronger environmental regs for landfills weren't passed until 1998.
Down the information hole
The unknowns about closed landfill sites are many - and that's the biggest problem. Most were capped, i.e., covered with a metre or two of dirt and left for dead, before there was even a Ministry of the Environment to regulate them. Databases kept by the ministry are woefully out of date and, until very recently, off limits to the public. The last comprehensive landfill inventory was published by the MoE in 1991.
Until the 90s, there was little in the way of technology to mitigate the leaching of harmful pollutants from closed landfills. None of Toronto's closed landfills, for example, are outfitted with liners to catch contaminants that may be leaking from the sites.
Safeguards in place?
At the 41 closed dumps where control systems are in place, pipes are used to release gases trapped beneath the surface and carry leachate to nearby sewer systems. In some cases, the volume of leachate generated by the dumps is such that pumping stations are used to collect the gunk and then redirect it into the sewer system.
Reason for alarm
The conventional wisdom is that the closed landfills, whatever their volatile mix of pollutants, do not pose an environmental threat. But there's no way of knowing that for sure, because no review has ever been undertaken of the sites. Nor is the city required to report problems to the province.
On the subject of closed landfills, the city auditor uncovered some flimsy oversight: no documentation that supervisory staff followed up on annual inspections, no record that the city implemented the recommendations of consultants hired to review the monitoring of closed landfills.
What the experts say
Peter Crockett, executive director, Technical Services, city of Toronto, on whether there's enough money in the current cash crunch to monitor closed landfills effectively:
"It's not that we're operating on a shoestring. We're doing everything we believe we need to do to keep those sites safe and secure and environmentally responsible."
Gord Miller, Environmental Commissioner of Ontario, on the potential for eco fallout:
"We produced bad waste in the old days. One can reasonably ask why we haven't dealt with these landfills. The answer, of course, is that we don't have the resources to do the job. We had better records in the 80s."
Estimated cost of caring for the city's closed landfills in perpetuity.
Amount currently in the reserve fund for the care of closed landfills.
Total annual revenue from landfill gas projects at three city-owned dumps.
First year routine monitoring of closed landfill sites was undertaken by the city.
161 Number of closed landfills in Toronto
41 Number monitored closely for gas or leachate activity
475 Number of gas probes monitored in and around closed dump sites
430 Number of water wells monitored
28 Number of streams tested for water contamination at or near closed landfill sites
15 Number of city staff overseeing the maintenance of closed dumps
3 Number of sites producing electricity