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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

Landfill mining has been proposed as an innovative strategy to mitigate environmental risks associated with landfills, to recover secondary raw materials and energy from the deposited waste, and to enable high-valued land uses at the site. The present study quantitatively assesses the importance of specific factors and conditions for the net contribution of landfill mining to global warming using a novel, set-based modeling approach and provides policy recommendations for facilitating the development of projects contributing to global warming mitigation. Building on life-cycle assessment, scenario modeling and sensitivity analysis methods are used to identify critical factors for the climate impact of landfill mining. The net contributions to global warming of the scenarios range from -1550 (saving) to 640 (burden) kg CO2e per Mg of excavated waste. Nearly 90% of the results' total variation can be explained by changes in four factors, namely the landfill gas management in the reference case (i.e., alternative to mining the landfill), the background energy system, the composition of the excavated waste, and the applied waste-to-energy technology. Based on the analyses, circumstances under which landfill mining should be prioritized or not are identified and sensitive parameters for the climate impact assessment of landfill mining are highlighted.

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To prospect an urban mine -assessing the metal recovery potential of infrastructure "cold spots" in Norrkoping, Sweden, 2013, Journal of Cleaner Production, (55) AbstractIn conventional mining, prospecting methods are used to increase the degree of certainty with regard to the stock of metals. Similarly, prospecting in terms of "urban mining" aims to increase the information about metal stocks available for recovery in the built environment. Infrastructure systems, such as for power supply and heating, are rich in copper, aluminum and iron (including steel). For a number of reasons, pipes and cables remain in the ground after being taken out of use or disconnected. This is also true for entire obsolete systems. In this paper, these infrastructures "cold spots" are viewed as hibernating stock with a significant potential for urban mining.The infrastructure systems for AC and DC power, telecommunication, town gas and district heating in the city of Norrköping, Sweden, have been quantified and spatially allocated with a GIS-based approach of Material Flow Analysis (MFA). About 20% of the total stock of aluminum and copper in these systems is found to be in hibernation. The findings also indicate that cables have been disconnected to a larger extent than pipes. As an example, cables for DC power, taken out of use in the late 1930s yet still in the ground, consist of 230 tonnes of copper. The results illustrate a clear tendency for larger stocks of hibernating copper and aluminum to be found in the central rather than the outer parts of the city. A reverse, ring-like pattern is true for iron, mostly because the central parts of the town gas pipes are used for fiber optics.Particular focus has been placed on the industrial area of Södra Butängen, which is slated for redevelopment and re-zoning from industrial to residential. Since the ground will be dug up for sanitation purposes anyway, the entire metal stock can be taken into prospecting consideration. Analysis shows that the chances of finding aluminum here are 28 times higher than in the rest of the city.We argue for an increased MFA focus on the heterogeneous complexity found in the details of the specific locale, rather than striving for generalized assumptions about the broader picture. In doing so, MFA could very well provide a tool for a future business line of urban mining of hibernating metal stocks.