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Stocks of finite resources in the technosphere continue to grow due to human activity, at the expense of decreasing in-ground deposits. Human activity, in other words, is changing the prerequisites for mineral extraction. For that reason, mining will probably have to adapt accordingly, with more emphasis on exploitation of previously extracted minerals.This study reviews the prevailing concepts for mining the technosphere as well as actual efforts to do so, the objectives for mining, the scale of the initiatives, and what makes them different from other reuse and recycling concepts. Prevailing concepts such as "urban mining," however, are inadequate guides to the complexity of the technosphere, as these concepts are inconsistently defined and disorganized, often overlapping when it comes to which stocks they address. This review of these efforts and their potential is therefore organized around a new taxonomy based on the umbrella concept technospheric mining, defined as the extraction of technospheric stocks of minerals that have been excluded from ongoing anthropogenic material flows.An analysis on the basis of this taxonomy shows that the prevailing mining initiatives are generally scattered and often driven by environmental factors, in which metal recovery is viewed as an additional source of revenue. However, development of technology, specialized actors and new business models and policy instruments, could lead to technospheric mining operations becoming a profit-driven business.

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Studies concerning landfill mining have historically focused on reclamation of land space and landfill remediation. A limited number of studies, however, have evaluated landfill mining combined with resource recovery, most of them being pilot studies or projects with little emphasis on resource extraction. This implies that many uncertainties remain related to landfill mining. With a growing interest in environmental concerns around the globe, the environmental evaluation of large-scale projects has become an increasingly important issue. A common way of conducting such an evaluation is to use Life Cycle Assessment (LCA). However, LCA by itself might not take into account all the inherent uncertainties in landfill mining. This article describes an approach for environmental evaluation of landfill mining that combines the principles of Life Cycle Assessment and Monte Carlo Simulation. In order to demonstrate its usability for planning and evaluation purposes, the approach is also applied to a hypothetical landfill mining case by presenting examples of the types of results it can produce. Results from this approach are presented as cumulative probability distributions, rather than a single result figure. By presenting results in this way, the landfill mining practitioner will get a more complete view of the processes involved and will have a better decision base.

Large technical systems serving the everyday needs of people, such as water supply systems, power grids or communication networks, are rich in accumulated metals. Over time, parts of these systems have been taken out of use without the system infrastructure being removed from its original location. Such metal stocks in hibernation thus constitute potential resource reservoirs accessible for recovery. In this paper, obsolete stocks of copper situated in the local power grids of two Swedish cities are quantified. Emphasis is also on economic conditions for extracting such -hibernating‖ cables. The results show that on a per customer basis, the two power grids contain similar amounts of copper, i.e. 0.04-0.05 tonnes per subscriber. However, the share of the copper stock that is in hibernation differs between the grids. In the larger grid of Gothenburg, almost 20% of the copper accumulated in the grid is no longer in use, while the obsolete share does not exceed 5% in the city of Linköping. For managers of local power grids, recovery of hibernating cables could be beneficial if integrated with other maintenance work on the grid. At the present price of copper, however, separate recovery of obsolete cables is not economically justified.2