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Cleaning up the Tar Ponds: Canada's Most Contaminated Site |
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SYDNEY, NOVA SCOTIA, Jul. 25 -/E-Wire/--
The largest contaminated site in Canada moved one step closer to the start of cleanup operations last week with the submission of a Joint Review Panel assessment of the proposed remediation plan. The Sydney Tar Ponds and Coke Ovens remediation plan calls for large volumes of contaminated materials to be either incinerated or stabilized for containment. The assessment report raises many concerns, however, about the technologies and proposed methods of containment planned for the clean up.
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With a stated goal to "reduce risks to people and the environment, and to create social and economic benefits" the remediation project may prove a model for large-scale contaminated site remediation and redevelopment across Canada provided the proper technologies, planning and project economics are employed. The extensive cleanup will require treatment of highly contaminated materials, groundwater and wastewater management, air quality control, and social and economic integration.
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The Joint Review Panel was tasked to review of the remediation plan put forward last year by the Sydney Tar Ponds Agency (STPA). After 17 days of public hearings in Sydney in April and May, the Panel submitted its report to federal Environment Minister Rona Ambrose and Nova Scotia Minister of Environment Mark Parent.
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The remediation plan for the Coke Ovens site and the adjacent Muggah Creek estuary, also known as the Tar Ponds, is designed to clean a massive area heavily contaminated with polycyclic aromatic hydrocarbon (PAH), polychlorinated biphenyl (PCB) and heavy metals from over a hundred years of steel production.
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The cleanup plan proposes using a combination of removal and destruction technologies and containment systems. It is expected to cost $327.5 million. Remediation of the Coke Ovens will be completed by 2011 according to the plan, while the Tar Ponds will require until 2014. However, the public and government must also be prepared to manage the Tar Ponds in perpetuity, says the Panel in its report.
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At the Coke Ovens site, containment structures would be erected to prevent groundwater from entering the site, and some contaminated materials would be excavated and sent by rail to a temporary incinerator for thermal destruction. A further 40 percent of the site with high contamination levels would be capped to limit surface water penetration, while other areas would undergo a form of bioremediation called landfarming to treat hydrocarbons in the soil before capping.
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The Tar Ponds site plan would require excavation of two sediment areas with high PCB concentrations (over 50 parts per million), and transportation by rail for incineration. Remaining sediments would be solidified in place using cement and other materials, and capped. An internal drainage system would be created to manage ground and seawater infiltration.
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Air pollution output and local air quality will require extensive monitoring to address potential environmental and health risks, particularly related to possible release of dioxins and furans.
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The Agency has proposed the use of rotary kiln or fluidized bed technology for the incinerator, with an extensive air pollution control system. A decision on what type of incinerator and pollution control system to be used and suppliers will be made following approval of a final remediation plan.
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The construction and remediation process at both sites will produce extensive wastewater that must be treated. STPA has estimated that the incineration facility will produce 63,100 litres of wastewater per day, to be treated onsite and held in storage tanks before discharge.
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The Agency expects that between 380 and 435 years of full-time employment will be generated during the construction phase, over 65 percent of which will be sourced within Nova Scotia.
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Areas of uncertainty
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Apart from the potential that the Tar Ponds may require long-term management, there are several other areas identified by the Joint Panel as needing further study. The Panel expressed concern at "a lack of demonstrated understanding of the ecological effects of the short- and long-term effects of remediation."
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As the Agency has a stated preference for the use of proven technologies, the Panel submits that solidification / stabilization technology will require further pilot studies in the specific context in which it will be used at the Tar Ponds that is, in an estuary with potential ground and seawater penetration. Although this is a secondary approach for the Tar Ponds, as most waste will be contained, the Panel felt the potential risk warranted further study.
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The most significant aspect of the plan, incineration of contaminated materials at a facility off-site, was found to be possible without
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significant adverse environmental effects, as long as appropriate technology selection and stringent regulation were applied. Although opposed by the Cape Breton Regional Municipality (which prefers total containment), incineration still seems to be the primary remediation option, though the Panels report raises sufficient concern to warrant further review.
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The Panel believes that under the terms of the federal Toxic Substances Management Policy, a complete study must be undertaken to weigh the relative benefits of incineration versus management in place. The Panel also submitted that a more complete assessment of the human health and environmental risks associated with incineration versus on-site treatment should be completed, indicating it may ultimately prove full containment is the preferable option.
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Health was the predominant issue raised during public hearings, with significant concern shown for the ability to monitor incinerator emissions continuously, and the regulatory requirements imposed on incineration. Presenters also questioned the potential effects on local water bodies, particularly those that supply water to nearby communities.
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The Panel also concluded that, despite being outside the immediate scope of the project, ensuring that the sites will have the capacity to support viable and sustainable use must be an integral part of the project design. While the agency acknowledged that the sites may need to be fenced-in if not suitable for use, points raised during the hearings suggested they be prepared for human use as soon as possible.
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Municipal leaders hope to create a new planning corridor from the Sydney harbour to the airport, with an industrial, business and technology park as well as a walking and cycling link to downtown. The Panel has recommended cooperation between the Regional Municipality and the tar ponds agency to develop a future land use plan.
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As it stands, the final remediation plan for the Sydney Tar Ponds and Coke Ovens site may look substantially different from the current strategy. Incineration or no incineration seems to be the big question, but issues of future land use, deployment of pollution-control technologies and water impacts are certainly of great importance as well.
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The federal and provincial governments will now weigh the Panels report and decide on what further actions to take in developing a plan. Likely these will include recommendations to the STPA on how to address Panel concerns regarding incineration and future use, and the results of this could possibly open the door to further private-sector cooperation. With a variety of established remediation solutions available in Canada, there is an opportunity to develop pilot projects to supplement the selected primary treatment option.
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Whatever the final remediation plan, it will be an important step forward in helping other communities in Canada to clean up unwanted remnants of our industrial past. Contact Info: Website : the Globe Foundation of Canada
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