The eighty-acre greenbelt, called Open Hearth Park, in Sydney, Nova Scotia, is the kind of park where one can spend a lovely afternoon. There are walking trails. Spots to enjoy the Sydney harbourfront or walk along Muggah Creek as it winds its way through the site. Off to one side a big, new soccer pitch. And, of course, a children鈥檚 playground.

One would be forgiven to forget that only a few short years ago it was the site of the most toxic place in Canada. A slough filled with deadly, poisonous chemicals 鈥 the legacy of more than a century of steelmaking in Sydney and the possible cause of terrible illnesses that plagued some neighbours.

鈥淛ust twenty years ago you wouldn't be allowed on this site,鈥 said Gary Campbell, who oversaw a $400-million clean-up funded by the Nova Scotia and Federal governments. 鈥淚t would all be fenced off. The steel plant didn't want people roaming around, you don't want people roaming around a heavy industrial site.鈥

Sydney Steel

That heavy industrial site got its start in 1900 鈥 the perfect place to bring together iron ore and lime from Newfoundland and coal from mines in Cape Breton, fed into giant blast furnaces. A 1956 film for the Dominion Steel Company, the-then owner of the mill trumpets: 鈥淪teel is indispensable to the modern age.鈥

The scenes of workers working around giant crucibles filled with molten iron, smoke belching into the air, flames licking from the ground, invoke comparisons with Dante鈥檚 inferno, a hell on earth. At one time the mill at Sydney was producing half of the steel made in Canada.

In one corner of the industrial site were the coke ovens, where coal was literally cooked to remove unwanted chemicals and impurities 鈥 chemicals like tar, benzene and sulphur were bled off and used when possible in the industrial process. But they also oozed onto the ground and as runoff into nearby Muggah Creek. Over time this toxic sludge built up in the Sydney Tar Ponds.

Gordie Gosse, the local MLA, recalled working in the plant 鈥 just as his father and grandfather before him had been steelmen. It was solid, good-paying work.

鈥淭he sulfur from the blast furnace when they opened the bleeders, the smell of the coke ovens when they quench the coke, you know, open the bleeders of the coke ovens and bled into the atmosphere,鈥 he told W5鈥檚 Todd Battis in an interview.

鈥淵ou didn't have to get have a watch in the community because the whistlers always blew. You knew it was twelve o'clock, four o'clock, eight o'clock, change of shift.鈥

In 1967 changes in technology, foreign competition and changes in ownership threatened closure. W5 was there as thousands protested what would have been an economic disaster.

The Nova Scotia government stepped in and kept the mill operating until economic reality set in and the plant was closed for good in 2000.

鈥淲hen the last shipment of rails left Sydney steel forever, you know and I watched them ship it away,鈥 recalled Gosse. 鈥淵ou remember the guys who died there, who you worked with, remember all of those men. You think about them and their families. All of those things, those memories are still there and very clear for everybody here.鈥

Maritimes musician Lennie Gallant captured that moment and those memories in his song 鈥淢an of Steel鈥 鈥 a lament to a passing industry and a city that suddenly found itself without the industry that was its heart.

He got the news this morning

It came without a warning

They're gonna shut the whole thing down

Seven hundred men out of work

Another paper promise gone down

Oh he's only forty-five but he's still alive

'Cause he's never fought a fight he hasn't won

A man of steel says, 鈥淒on't ever break

Until the job is done.鈥

What remained: the Tar Ponds 鈥 a deep, wide toxic soup. And the daunting task of cleaning it up.

The Sydney Tar Ponds Agency was created to oversee the job. After decades of study the plan was to entomb the goop by mixing it with cement and hardening it into stone, then to cover that with earth and sod and to turn it all into a park.

Walking across the site with Gary Campbell, if you didn鈥檛 know it you鈥檇 have no idea what lies beneath the ground.

鈥淲e would have been standing where we are right now, on about three to four metres of the kind of stuff you'd roll on your driveway, tar product. It's amazing,鈥 he said.

鈥淣ot once in my wildest dreams could I ever imagine that it could be what it is today, growing up less than three hundred feet from the site itself as a kid,鈥 said Gosse.

Frederick Street

There is pride in the new urban jewel in Sydney but pain as well, particularly for some former neighbours whose homes on Frederick Street had abutted the site. For decades they have been fighting for compensation for serious illnesses they claim were caused by the toxic chemicals next door and which seeped onto their properties and into their homes.

鈥淚 think it's beautiful down there. Um, but in fifty years time, twenty years time, is anyone going to know what's underneath it?鈥 asked Juanita McKenzie.

In 1998, McKenzie and several of her neighbours were featured in a W5 report about their fight against government at every level. They were concerned that the hulking mill, coke ovens and tar ponds were responsible for illnesses plaguing their families.

In one scene McKenzie is seen listing the sicknesses they had suffered: 鈥淐ancer, asthma, heart and stroke, skin diseases, kidney infections, headaches, sore throats, ear problems, Alzheimer's, pregnancy problems, breast diseases, eye problems, blood disorders and others.鈥

鈥淚t鈥檚 like Love Canal,鈥 chimed in another neighbour, Debbie McDonald, referring to the Niagara Falls, New York neighbourhood where a chemical company had dumped 21,000 tonnes of toxic waste. By comparison, a century of steel-making in Sydney poured 700,000 tonnes of poisons into the tar ponds.

鈥淲hen we first bought the place I was going down the basement and there was yellow stuff down there and I never really clued in that time what it was,鈥 recalled McDonald in an interview. 鈥淏ut when they started looking at the other side of the road with the brook, I started putting two and two together, and the same colour and it was in our basement so we got our basement tested and it was arsenic in the basement.鈥

When Nova Scotia鈥檚 Chief Medical Officer at the time suggested exposure to the chemicals would not harm health Juanita McKenzie exploded. 鈥淎nd I just got back today from the hospital, from Halifax, with my husband, and he's not well. And then you're telling me that there's NO problem? I can't accept it, and I won't accept it.鈥

Fifteen years later she still shakes her head at the insensitivity. 鈥淭o sit there and to have them tell me there's nothing wrong? Michelle had been in the hospital the day before, she was urinating blood like, I don't know how many times, and they're telling me there's nothing wrong? Like how dare you. I might not be up to your level of education, but I'm dang-well not stupid, you know. And I knew there was a problem, and come hell or high water I was going to find out and prove them wrong.鈥

In the end they won a partial victory. The Federick Street residents were moved and their houses torn down. These days vacant lots and weeds are all that remain.

鈥淚f I had known before we bought that house there, we wouldn't have bought the house there,鈥 said MacDonald. 鈥淟ike, I knew what chemicals were in the coke ovens, my father worked there, he told me of benzene, a by-product of coke, and a couple of other chemicals, I knew the chemicals that were there.鈥

Three years ago cancer claimed one of the neighbours, Louise Deveaux. Debbie MacDonald鈥檚 husband, Ron, also died of the same disease. And Juanita McKenzie has struggled with her health.

鈥淚 had kidney cancer and lost my right kidney to cancer. I've had carcinoma, I've had spots removed, skin cancer. I have a few underlying health problems I'm dealing with.鈥

The former residents鈥 fight continues through a class action lawsuit. It was certified by a Nova Scotia court but the province and the federal government have appealed. The Court of Appeal has reserved judgement.

But for a new generation in Sydney the tar ponds are now a buried memory. On a sunny day in the park it is easy to forget that only a few metres below, in a tomb of toxic cement and soil, lies the city鈥檚 toxic past.