Year: 2018
Type: other
Abstract: The mining industry generates millions of tons of tailings in Canada that are a major concern for the environment, commonly inhibiting the regrowth of vegetation and therefore presenting a long-term risk for metals leaching, as well as reducing other environmental services of natural ecosystems. Charcoal used as a soil amendment ("biochar”) has recently been proposed as a mitigation tool for the restoration of these sites as it promotes plants growth and directly sequesters carbon in the soil for hundreds to thousands of years. One critical step in examining operational use of biochar are analyses that examine the economic and environmental costs and the benefits of restoring mine tailings with biochar. In this study, we investigate alternative economic and environmental solutions to restore the native forest with biochar at the Goldcorp Musselwhite mine, located in the Ontario Far North Region, Canada. Based on a discounted cash flow analysis, we reviewed the economic impacts of specific biochar amendment rates coupled with different alternatives for biochar access. These alternatives include the importation of high-carbon wood ash from an external supplier, the local production of biochar, either through the use of a mobile pyrolyzer or a wood gasifier, using various feedstocks, including local forest residues, wood pallets or imported wood-chips/sawdust. The environmental benefits of each alternative were also measured in terms of C sequestration, with an estimation of the potential carbon credit income that could be generated under proposed Ontario cap-and-trade guidelines. Our results indicate that the import of high-carbon wood ash from the Thunder Bay area would be the least costly and easiest solution to implement for the mine. The possible utilization of high-carbon wood ash in the restoration of mine tailings has multiple environmental and economic benefits, as this material is usually sent to landfill at an economic and environmental cost for both the companies and the public. We also conclude that technical, logistical, and cost barriers currently limit the implementation of local biochar production in Ontario, and these limitations are especially pronounced in remote sites such as the Ontario Far North region.
Source: TSpace (University of Toronto)
Author: Annonciade Murat
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2982062166