Sydney Tar Ponds

Over the last century, runoff from the nearby coke ovens site, associated with a now-decommissioned steel mill[1], filled the estuary with a variety of coal-based contaminants and sludge. Efforts to clean up the waterway have been dogged by false starts, delays, and political controversy. After extensive public consultation and technical study, a CDN$400-million cleanup plan, jointly funded by the Government of Canada and Nova Scotia, awaits further environmental assessment.

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Geography

The Tar Ponds are located at (46°08′ 45” N 60°11′ 20” W). The North Pond and the South Pond have a combined area of 31 hectares (77 acres), and contain 700,000 metric tonnes of contaminated sediments. The nearby coke ovens site spans 68 hectares (168 acres) on a hill overlooking the estuary. It is estimated to contain 560,000 tonnes of contaminated soil.

A small stream, the Coke Ovens Brook Connector, connects the coke ovens with Muggah Creek and the Tar Ponds themselves. It served as the main pathway for contaminants migrating from the coke ovens to the Tar Ponds. To the east of the coke ovens, and uphill from them, an abandoned municipal dump served as an additional source of contaminated groundwater, or leachate.

The polluted sites lie in the middle of the former city of Sydney (estimated population 25,000), now joined in municipal amalgamation into the Cape Breton Regional Municipality (CBRM) (2001 population 105,968).

Almost all of the contaminants derive from coal, but the Tar Ponds include two pockets containing an estimated total of 3.8 metric tonnes of polychlorinated biphenyls (PCBs).

Although often described as such, the Tar Ponds are not Canada’s largest or worst contaminated waste site. Hamilton Harbour is larger, as are several sites in the Canadian Arctic. The contaminants in the Tar Ponds and coke ovens are not unusual. Almost all result from coke production, one of the most common industrial processes of the 19th and 20th centuries.

History

In 1901, a major steel works was opened on Sydney Harbour by investors from Boston. Sydney had everything needed for steelmaking, including locally mined coal, nearby iron ore from Bell Island in Newfoundland, a good harbour for shipping along the Eastern Seaboard, and plenty of cooling water. By 1912, the mill was turning out nearly half of Canada’s steel production.

The steel mill at Sydney and the nearby coal mines which fed it operated for almost a century under a variety of owners. In the mid-1960s, the Dominion Steel and Coal Company announced that it was planning to close the steel mill and mines as they were proving to be uneconomic. In response to the threatened loss of thousands of jobs in a region having already poor employment prospects, the provincial and federal governments coordinated a plan to nationalize the operation.

The government of Nova Scotia agreed to take over the operation of the steel mill, which it renamed "Sydney Steel Corporation" (SYSCO). The government of Canada agreed to take over the operation of the coal mines and the Sydney and Louisburg Railway, which it renamed "Cape Breton Development Corporation" (DEVCO). The nationalization was being done as a means to gradually wean the Sydney-Glace Bay area from an industrial-based economy into a more diversified post-industrial economy by the end of the 1970s. One of the properties DEVCO and the federal government also inherited was a coke oven plant, located adjacent to the steel mill, which slowly cooked coal to produce coke as a fuel for the provincially-owned SYSCO blast furnaces.

The plan to diversify the Industrial Cape Breton economy and gradually shut down the coal mines and steel mills was fraught with problems ranging from global economics to local politics. The OPEC oil crisis following the Yom Kippur War in 1973 resulted in the federal government actually expanding DEVCO coal production under a 30 year plan, rather than scale back production. Similarly, steel prices and local protests over the loss of jobs forced the provincial government to implement plans by the late 1970s and early 1980s to upgrade the steel mill from a blast furnace/iron ore process to the electric arc/recycled metal process.

When SYSCO closed its blast furnaces in 1988 to prepare for converting the steel mill to the electric arc process, DEVCO also shut its coke ovens which had supplied the mill with fuel for most of the previous century. The conversion to the electric arc process took almost 2 years and the mill only operated from 1990-2000 when production ceased. The mill is now decommissioned and in the process of being dismantled.

Meanwhile, in 1982 scientists from the Department of Fisheries and Oceans discovered polynuclear aromatic hydrocarbons (PAHs), a family of chemicals commonly produced by incomplete combustion of organic material, in lobster caught in Sydney Harbour off Muggah Creek. They ordered the South Arm of the harbour closed to lobster fishing, and fingered runoff from the federally-owned coke ovens site into the Tar Ponds as the likely source of contamination. This led to the provincial and federal governments arriving at an agreement whereby the Tar Ponds pollution created by the coke ovens site was made a federal responsibility.

In 1986, Canada and Nova Scotia signed a $34-million agreement to dredge the Tar Ponds and pump the sediments through a mile-long pipeline to a temporary incinerator and power plant. After many delays, the incinerator was completed, and passed required air emissions tests, in 1994. However, the pipeline system proved unable to handle the thick, lumpy, Tar Ponds sludge, and the project was abandoned in 1995.

In 1996, the Nova Scotia government proposed a plan to bury the Tar Ponds under slag procured from the steel mill. By this time, the project had attracted local critics, who condemned the plan.

In 1999, the federal, provincial, and municipal governments jointly funded a community organization, the Joint Action Group (JAG), with a mandate to seek community consensus on cleanup options. The three governments also embarked on detailed environmental site assessments, and a variety of preliminary cleanup projects. JAG eventually sponsored more than 950 public meetings. No clear consensus on cleanup technologies emerged. Governments, meanwhile, generated more than 620 technical and scientific reports on the problem, and possible solutions.

Cleanup

At the Tar Ponds, treatment will consist of solidification and stabilization, a process by which contaminated sediments are mixed with Portland cement powder or similar hardening agents. At the coke ovens, contaminated soils will be treated with a form of bioremediation known as land farming, in which hydrocarbon-eating bacteria and nutrients are tilled into the upper surface of the soils. The sites will then be contained within a layered cap and impermeable sidewalls, and then landscaped for as yet undetermined future use.

A special operating agency of the Nova Scotia government, the Sydney Tar Ponds Agency, will manage the cleanup on behalf of the two governments, in partnership with the Department of Public Works and Government Services which is the lead federal agency. Fifteen community groups in such fields as environment, health, business, labour, religion, recreation, municipal government, environment, and higher education, will contribute delegates to a Community Liaison Committee that will serve as a sounding board for project managers during the cleanup.

Controversy

Opinions divide on the best cleanup method. Some residents favour digging up and destroying all of the contaminants. Others prefer not to disturb the contaminated material at all. The Sierra Club of Canada opposes plans to incinerate the PCB materials in favour of novel destruction technologies such as hydrogen reduction and soil washing. Project managers say the community has asked that only proven technologies be used.

Next steps

By law, the main cleanup must undergo a federal environmental assessment, expected to take at least two years. A proposal to have an independent panel conduct the environmental assessment is currently under debate, with a decision expected by May 2005.

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