Cleaning up one of Canada’s most polluted sites is estimated to cost taxpayers more than four times what was expected. Finance Canada recently approved a new $4.38 billion cost estimate to rehabilitate the Giant Mine, a former gold mine that operated from 1948 to 2004 within Yellowknife city limits. The federal project was estimated to cost just under $1 billion in 2013, but that didn’t take into account inflation, contingency and project management costs, and the fact that restoration plans have since expanded. “We’ve heard from our rights and stakeholders and have improved the project since the original cost estimate came out,” said Natalie Plato, deputy director of the Giant Mine Remediation Project. “We think this is a very positive initiative for Yellowknife and the surrounding area.” Northwest Territories MLA Kevin O’Reilly, who intervened in the Giant Mine cleanup plan as an environmentalist, said he was not surprised by the new price. “It’s certainly a huge number, but it shouldn’t surprise anyone,” he said. “Travel costs have skyrocketed lately, while in terms of getting contractors and so on.” O’Reilly said he would like to see a breakdown of the cost estimate. He said he had to push to find out the earlier estimate, eventually getting the number by submitting an access to information request. The $4.38 billion cost estimate includes all costs for the restoration project since 2005 and projected future costs during active restoration. While the remediation was originally scheduled to be completed in 2031, that deadline has been pushed back to 2038. However, some aspects of the project, such as the 237,000 tons of highly toxic arsenic trioxide dust stored underground at the site, will require ongoing care and maintenance. O’Reilly said the costs for long-term care will likely be significant. Since the initial cost estimate was released, the project has undergone a water permitting process and an environmental assessment, which resulted in 26 legally binding measures that had to be completed before remediation could proceed. Other changes include the creation of an oversight board, community benefit and contribution agreements, and a health impact monitoring program to measure levels of arsenic and other contaminants in residents in Yellowknife, N’dilo and Dettah through biological sampling. Plato said another change requested by stakeholders was filling eight open pits at the site instead of leaving them open to protect the basement from flooding. The scale of the mine cleanup is huge, with the area spanning more than 900 hectares. It also has 13.5 tonnes of contaminated soil, a landfill, six waste tanks and 100 buildings, including an abandoned town where former workers’ homes contain asbestos. Restoration work over the next decade will include building a new water treatment plant, deconstructing the old city, underground stabilization using a mixture of cement, waste and chemical additives, and freezing underground arsenic chambers using 858 water heaters, which are basically large . tubes filled with pressurized carbon dioxide. This report by The Canadian Press was first published on November 10, 2022. This story was produced with financial assistance from Meta and the Canadian Press News Fellowship.
