Fire Threatens Disaster in Canada : Environment: Thousands of burning tires could produce tons of oil laden with toxic chemicals.

A fire burning for more than a week in a tire dump the size of 18 football fields is threatening to become a major environmental disaster here in southern Ontario province, officials say.

If just half of the estimated 14 million tires in the dump were to liquefy in the fire’s intense heat, one Canadian expert on tire recycling has said, they could produce more oil than last year’s notorious Exxon Valdez oil spill in Alaska. And such oil, containing toxic chemicals, would be even harder to clean up than the Exxon Valdez disaster, warned the expert, Brian Latto, a mechanical engineering professor at the University of Ontario.

“If (the oil) goes down into the soil, you can’t clean it, whereas on the sea, at least you can clean it with detergents,” Latto said.

Police say they believe an arsonist started the fire. Hundreds of area residents had to be evacuated last week as the top layers of the tires burned and huge clouds of black smoke billowed into the sky. Now, however, the top layer has melted into a lava-like ooze covering the burning tires below, creating a structure resembling an oven.

Less black smoke is evident now, and some of the residents have ventured home. But the fire is still burning, and Latto said there is enough oxygen beneath the pile’s surface to fuel the blaze for weeks or months. In the United States, tire fires have burned for six months or longer.

“The tires are a beautiful rabbit warren for air to get in, like wood in a grate,” he said, adding that temperatures inside the pile could be as high as 4,532 degrees Fahrenheit--hotter than the melting point of steel.

Extreme heat turns rubber into oil, and a single tire can generate about two gallons of oil as it liquefies. Thus, if half the pile at Hagersville were to melt, about 14 million gallons of toxic oil could seep into the farmland and ground water nearby. The Exxon Valdez leaked about 11 million gallons of oil into the sea.

Latto noted that this is a worst-case calculation and that the Hagersville fire could ultimately send much less oil into the ground water, depending on wind, soil conditions and other factors.

Even so, the oil from the burning tires contains cancer-causing benzene and toluene, along with other chemicals.

Firefighters in the region have expressed concern that the water they have been using to fight the blaze is actually helping to leach the oil and chemicals into the ground. Last weekend, they stopped spraying water on the fire and dug ditches for the dirty water to run into.

Then they wrestled huge hoses into place at the ends of the ditches and went to work trying to skim the oil off the water and pump it into tanker trucks. They said they hoped to reuse the dirty water to extinguish the flames, but they added that some of the contaminated liquid will inevitably seep into the ground.

Officials said ground water in the Hagersville area flows toward Lake Erie at about 500 yards per year.

The fire broke out at Edward Straza’s Tyre King Tyre Recycling Ltd., where neighbors said Straza made a living receiving unwanted tires from service stations, charging garage owners 50 cents to $1 apiece to dump the unwanted tires on his land. They said he had a sharp eye for picking still-usable tires out and reselling them.

But most of the tires just sat on his land, heaped in piles at least 30 feet tall. Straza even had tires in his front yard.

Such sites are fairly common in industrialized countries, Latto said.

After a small fire at the dump site several years ago, Ontario officials had ordered Straza to fence off the tires, to arrange them in separate heaps so that firetrucks could drive among them if necessary and to build a 100,000-gallon water reservoir.

However, Straza had argued that the cost of reorganizing the tires in separate piles and digging a reservoir would put him out of business. He appealed the order, the tires stayed put and the authorities had not yet ruled on the appeal when the current blaze broke out.