It's the result of nearly a century of coal mining and steelmaking, which left behind 900,000 tonnes of chemical waste and untreated sewage. About 5 per cent of that waste, or 45,000 tonnes, is contaminated with dangerous concentrations of polychlorinated biphenyls, or PCBs.
First discovered in the late 1800s, PCBs were used throughout much of the 20th century as a fire-resistant ingredient in industrial materials such as inks, paint, caulking compounds, coolants and lubricants in electrical equipment.
By the late 1970s links to cancer, skin diseases, nervous system disorders, birth defects, reproductive problems and other health issues led to a North American ban on the substance in 1977.
Nearly 30 years later decades of PCB use still plague hundreds of communities across Canada. Like Sydney, they are forced to live with negligence of the past and are only now seeing a significant commitment to dealing with the problem.
Last spring, Ottawa and the Nova Scotia government said they would spend $400 million over 10 years to decontaminate the tar ponds, with $120 million in federal money coming from $3.5 billion earmarked in the 2004 federal budget.
'This material will be removed and safely destroyed using a proven technology such as high-temperature incineration,' states the Sydney Tar Ponds Agency on its website. 'Incineration is currently the most commonly used method of destroying PCB waste in North America.'
Most common. Maybe. But is incineration the best way to go?
'I've seen these ponds myself, and it's a nasty mess,' says Adam Sumel, co-founder and chief executive officer of Vancouver-based Sonic Environmental Solutions Inc., who from the opposite side of the country believes he's got a better way to clean up Sydney's contaminated soils.
In essence, Sumel wants to give the soil a good shake, using what he describes as the 'world's biggest vibrator.'
Seriously, Sonic Environmental has developed and patented a system that uses the natural resonance of a 14-foot, 2.8 tonne steel bar to create an effect known as 'sonic agitation,' which removes PCBs from soil and then destroys them completely by altering their chemical composition.Resonance can be a powerful thing when properly harnessed. Ever had an annoying vibration in your car when it's in a certain low gear? Ever used a tuning fork, or slid your finger around the rim of a crystal wine glass only to hear a vibration sound grow louder and more intense? What you're experiencing is the natural resonance of objects.
The Tacoma Narrows Bridge in Washington was destroyed in 1940 after a steady but not particularly strong wind caused the steel structure to reach its natural resonance. Within a few minutes of twisting and swaying, as if it was a rubber structure, the bridge completely collapsed. Memories of seeing the video in a Grade 10 physics class are still fresh in my mind.Sonic Environmental has figured out a way to take advantage of this phenomenon.
'We actually drive this steel bar into its resonance, capture its energy and then apply it,' says Sumel, explaining that each end of the bar is suspended by large magnets, allowing it to vibrate without touching — that is, destroying — anything.At a site such as the Sydney Tar Ponds the contaminated soil would be dug up and mixed with a solvent into slurries. The mixture would then be pumped into the company's sonic generator, where extreme agitation of the steel bar shakes the PCBs from the soil.
Sodium is then dispersed into the PCB-filled solvent. Again, the intense vibration of the steel bar accelerates a chemical reaction, stripping chlorine from the PCBs — in other words, destroying them. When the solvent is recovered from the soil, the end product is salt and low-grade fuel. And, most importantly, clean soil.Sumel says incineration has many problems. First, you've got to relocate the soil to an incineration facility that could be several hundreds of kilometres away. Not only can this become costly, some people don't take kindly to having trucks hauling contaminated loads through their communities, even if they're en route to somewhere else.
Another risk with incineration, which is why many countries have banned it, is that incomplete combustion of the PCBs could lead to the release of even more toxic particulates into the air. That's why when incineration is chosen temperatures need to be consistently above 1,200 degrees C to assure a complete burn.The physical risks involved with incineration have created political risks. Many politicians simply don't want to go down the incineration route, for fear of a constituent backlash.
On the other hand, Sonic Environmental's system is mobile — you can transport all the components by air or train on eight skids and install it onsite within about 10 days, says Sumel, pointing out that a system is already in operation in British Columbia and is processing 3,000 tonnes of soil.And, as described above, it's relatively 'green' in the sense that it doesn't carry the same risks — and risk perceptions — of incineration. Sumel says it also uses less power than a typical incinerator system, meaning it's spewing fewer greenhouse gases into the atmosphere.
Environment Canada said earlier this month that it will begin cleaning up the first 100 of about 4,000 contaminated sites under the responsibility of the federal government, including the Sydney tar ponds.'We know there are a few of those heavily contaminated with PCBs,' says Sumel, who says he's met with Environment Minister Sté,phane Dion to discuss the problem. 'We're moving towards getting a piece of that. One of the first things we need is a demonstration site with the government.'
But he doesn't expect to get any traction from government anytime soon. It could be nearly a year, for example, before there's action on the Sydney tar ponds. As far as Canada goes, Sonic is in talks with a large international company about cleaning up a private site in eastern Canada. Similar partnerships are being discussed on other fronts.'The ones we work well with we'll jump into bed with,' said Sumel. Partnering with bigger names in the industry is essentially Sonic Environmental's strategy, which is heavily focused on creating joint ventures in the United States, the European Union and Japan. The company has signed an agreement that could see it establish a joint venture in Eastern Europe.
And it's not just environmental regulation creating these opportunities. Fact is, land for development in certain high-population cities is becoming scarce, forcing developers to clean up dirty or 'brownfield' properties that in the past have been overlooked.'Brownfield opportunities are becoming increasingly important as urban land development opportunities become limited,' the company said recently.
Japan could offer a unique opportunity. 'Japan is addressing the soil problem right now,' says Paul Austin, vice-president of marketing at Sonic Environmental.'People don't like to talk about their PCB problems, and Japan is very much in that mode. But the government recognizes it, and you're starting to see the big manufacturers looking for innovative technologies they can import to deal with this problem. The fact is, you can't incinerate in Japan.'
Sonic Environmental's technology is not limited to PCB decontamination, and over time the sonic generator will be adapted for many different industrial applications — such as mixing chemicals — but Sumel and his team decided to prove the concept by attacking the PCB problem first.'To do something good for the world and make money is quite honestly a good feeling,' he says.