Existing approaches to reducing environmental impacts along the metal production and consumption chain are focused largely at the plant scale for primary production, rather than considering the whole metal cycle. As such, many opportunities for systemic improvements are overlooked. This paper develops an approach to designing preferred futures for entire metal cycles that deliver reduced carbon footprints. Dynamic material flow models in Visual Basic® are used to provide life-cycle-impact-assessment indicators, which help identify key intervention points along the metal cycle. This analysis also identifies which actors or agents along the value chain are responsible for, or can influence, behaviour which affects environmental performance. With this information, it is possible to evaluate different scenarios for transition paths to achieve reduced impact. These scenarios consider combinations of new technology, increased metal recycling and demand management strategies. A case study for the copper cycle in the USA shows that to meet a CO2 reduction target of 60% by 2050, innovative technologies for primary processing of mined ore will play a limited role, due to their increasing impacts in the future associated with mining ever lower ore grades. To compensate for this whilst meeting demand projections, recycling of old scrap would be required to increase from 18% to 80%, requiring extensive collaboration between primary and secondary producers. An alternate scenario which focuses on demand reduction for copper by 1% per year, meets the CO2 target whilst only requiring an increase in the recycling rate from 18% to 36%. Together, these suggest that there is merit in examining the 'metal-in-use' stage of the metal value chain more closely in order to achieve targeted reductions in CO2. The approach also highlights the inherent trade-offs between different aspects of environmental performance which are required when pursuing CO2 reduction targets.
The Yukon Environmental and Socio-Economic Assessment Board (YESAB) has recommended that the controversial Carmacks copper mine project can go ahead, providing that the Western Copper Corporation (TSX: WRN) complies with 148 conditions to mitigate potential adverse impacts. The tiny community of Carmacks with a year-round population of 500 is still considered an important service center for mining and for transportation, a century after it was a popular rest stop for the Yukon gold rush. However, members of the Little Salmon Carmacks First Nation want Western Copper to negotiate a better environmental engineering solution as part of an Impacts Benefits Agreement with the community. Located 38km northwest of the Village of Carmacks and 192 km north of Whitehorse in the Yukon Territory, the Carmacks copper project is planned to be an open-pit operation that will yield about 14,000 tonnes of copper cathode annually. Western Copper has targeted production to begin during the fourth quarter of 2010. Among the comments and concerns raised with the YESAB were routing of mining-related traffic, the heap leach detoxification process, sludge management, heap leach liner performance, and the estimates of closure costs. Among the comments and concerns raised with the YESAB were routing of mining-related traffic, the heap leach detoxification process, sludge management, heap leach liner performance, and the estimates of closure costs. The YESAB Executive Committee said it was satisfied that: Western Copper adequately consulted with the First Nations in whose territory, and the residents of any community in which the project will be located or might have significant or socio-economic effects; The project proponent provided sufficient information in the project proposal to allow for the assessment of potentially significant effects; Significant adverse environmental or socio-economic project and cumulative effects identified within the scope of the scre
