Opportunities for Urban Mining of Rare Earth Elements in Amsterdam

(1)

Opportunities for Urban Mining of Rare

Earth Elements in Amsterdam

Final Report

Interdisciplinary Project Stef Zuidervaart |11290986 Pieter van der Molen |11334886 Gijs Neerincx |11296429 Puck Schoon |11327014 Word count: 7836 Expert: Emily Burdfield Steel Teacher: Anne Uilhoorn Institute for Interdisciplinary Studies (IIS), University of Amsterdam Date: May 31, 2020

(2)

Abstract

This report will contain an interdisciplinary study regarding the opportunities of implementing Urban Mining (UM) in the city of Amsterdam, employing a literature study and ArcGIS mapping. UM is the recycling of Rare Earth Elements and Metals (REE/Ms) which are found in urban waste streams. In Amsterdam it is deemed to be a novel enterprise with untapped potential, due to the lack of mining possibilities in the Netherlands. Therefore, UM provides the possibility to harvest REE/Ms without being dependent on other countries. Using these non-renewable REE/Ms, the growing demand for products containing them will be tackled. The circular economy uses and reuses all elements in a system, aiming to neither discard nor add any products and elements when unnecessary. This can address the problem around growing waste streams, in particular e-waste. In order to discern the possibilities of UM for the city of Amsterdam, this paper employs Life Cycle Assessment, Material Flow Analysis, Multi Criteria Analysis and Extended Producer Responsibility to explore these opportunities for the mining of REE/Ms in the urban city of Amsterdam. The research question therefore is: “What are the Opportunities for the UM of Rare Earth Elements and Metals (REE/Ms) in the city of Amsterdam?”.

The results show that the recycling of metals could have a positive impact on the lowering of emissions and waste products. However, there is still much debate and uncertainty on the financial feasibility of UM for the Amsterdam metropole. Furthermore, a waste treatment facility (WTF) is required to process this waste, which could potentially end up polluting the surrounding environment. These externalities make it impossible to situate a WTF in the densely populated Amsterdam area with current policies. It is concluded that at the moment the possibilities of integrating UM into the Amsterdam metropole are slim. The study is finalized with the recommendation to be more lenient regarding the proximity principle of the WTF, which is regarded as the main roadblock for the integration of UM.

(3)

Introduction

The concept of a circular economy (CE) has recently gained considerable traction within the academic community (Geissdoerfer, 2017). A CE is best described as an economy that is designed to be regenerative/restorative, which is realized by closing the loops of the material flows and thus maintaining the highest utility value of these materials (Geissdoerfer, 2017). The growing popularity of a CE is mainly due the fact that it is regarded as a concept that could address the growing pressure on non-renewable resources (Lieder & Rashid, 2016). The global exponential economic growth since the start of the industrial revolution and the growing human population have been the main drivers of the growing stresses on natural resources (Yuan & Moriguichi 2006). Meadows et al. (1972) predicted in their ‘Limits to growth’ report that the resource needs of society cannot be met by the finite reserves on earth. A CE can alleviate the pressures on the reserves of non-renewable resources by closing the loops of the life cycles of products (Geissdoerfer, 2017). A notion that is associated with a CE is Urban Mining (UM). This research will revolve around the opportunities of UM within the Amsterdam metropole. UM is here defined as: “...the process of reclaiming compounds and elements from any kind of anthropogenic stocks, including buildings, infrastructure, industries and products (in and out of use).” (Mining, 2015). This broad definition includes all anthropogenic stocks found in the urban waste streams; however, the main focus of this study is on 17 elements and metals which are categorized as rare earth elements and metals (REE/Ms) (Humphries, 2010). The REE/Ms will be further contextualized in the theoretical framework.

The scientific community has been aware of the consequences of the depletion of certain elements and metals, and the impact on the supply chain of clean and reliable energy, for some time. This is named as an important challenges that mankind has to face this century (Lewis & Nocera, 2006). As the world population continues to grow, the demand for these resources is likely to follow. Accompanied by rising costs of extraction processes, and increasing the need for more novel recovery techniques (Dodson et al., 2012). Societies increasing exposure of the above-mentioned price fluctuations and resource scarcity illustrates the necessity and relevance of a recycling associated concept such as UM (Arora et al., 2017).

UM is a rather novel approach towards recycling, nonetheless the concept has already been a research topic for stakeholders in a multitude of studies and covered by news outlets, signifying the potential that academics and the public see in it (Krook & Baas, 2013). At the moment various cities and countries have (partly) instituted UM or an associated adaptation into their respective waste management structures. Brazil is an exemplary country that is familiar with the notion of UM for a longer time. The UM structure within Brazil is for the most part made up of a multitude of informal neighbourhood initiatives that systematically scour the urban waste streams for useful resources. India

(5)

and the city of Zurich are just starting the trajectory and are carefully testing its viability. (Simoni et al., 2015 and Arora et al., 2017). The most promising developments are taking place in China where certain UM structures within cities are already more cost-effective than conventional mining (Zeng et al., 2018). These examples illustrate that UM, although gaining increasingly more exposure in different parts of the world, it has not been fully implemented anywhere. Thus the state of the art of UM is still in its infancy and for the majority based on a theoretical basis provided by the considerable scientific literature pool regarding the subject (Krook & Baas, 2013). To advance the state of the art of UM, a careful examination of the knowledge gaps regarding the implementation of UM into the existing the waste management structure is necessary. In the Amsterdam case these knowledge gap are related to the novel character of UM, as the Amsterdam has not been acquainted with the concept. First, It has not yet been established what possible complications could emerge along the way and if UM will eventually be profitable for the city of amsterdam. Moreover, not all materials in the anthropogenic stock are viable for extraction, thus an analysis to discern which materials should be reclaimed is required. To bridge this knowledge gap the following research question has been adopted: “What are the Opportunities for the UM of Rare Earth Elements and Metals (REE/Ms) in the city of Amsterdam?”. The corresponding sub-questions will be explicated within the problem definition section.

The study draws its scientific relevance from three varying aspects. Firstly, the multiple of knowledge gaps within the research area (Krook & Baas, 2013). Moreover, UM is a site-specific concept, as cities differ from each other in their waste content, outlay and waste treatment guidelines. At the moment only handful studies have been conducted on UM regarding Amsterdam, the research can help bridge this knowledge discrepancy. Lastly, despite being a new concept, UM is getting increasingly more traction within academic circles (Graedel, 2011).

Due to a number of traits characterizing UM, the concept can be regarded as a complex system. These characteristics include: Connectivity of subsystems, observer dependence, path dependent and resilient (Boulton & Allen, 2007). This complex nature necessitates an interdisciplinary approach (Menken & Keestra, 2016). The interdisciplinary approach will be justified within the problem definition section.

This report will first present a theoretical framework, where we will explicate the different theories and concepts which function as the foundation for the desired analysis. Secondly, an extensive definition of the problem will layed out and divided in four sub-questions. Thirdly, the integrative framework i.e. the four analysis tools of Kiddee et al. (2013) will be outlined and the methodology will describe how this framework will be applied for the analysis, which will culminate into the results. In this results section we will describe the urgency of a UM for the Amsterdam metropole,

(6)

anticipate possible complications along the way, discern which materials are viable for extraction and outlay the financial viability of UM for Amsterdam.

(7)

Theoretical framework

Rare Earth Elements and Metals

Rare Earth Elements and Metals (REE/Ms) have an important role in current societies and economies. REE/Ms have beneficial properties that make them an essential element in many applications of modern technology. This paragraph will further investigate the concept, applications and future of REE/Ms in the future.

REE/Ms are a relatively new concept in human societies. They were discovered in Sweden around the 1800s. However, the identification of all the REE/Ms took more than 150 years (Chakhmouradian & Wall, 2012), mainly due to the difficulties isolating these elements from their parent material and their similar characteristics.

There are seventeen metals classified as REE/M (Figure 1). Fifteen of these elements are within one group according to the periodic table: the lanthanides. The other REE/Ms are yttrium and scandium. These do not define as lanthanides, although due to their chemical and physical properties these two elements have a similar behavior as lanthanides.

Figure 1: The different REE/Ms, lanthanides, scandium and yttrium. Source: Rare Element Resources, (2020)

(8)

REE/Ms have unique specific electronic, optical and magnetic properties and these properties make that they have excellent characteristics for many applications within modern technologies (figure 2). Without REE/Ms, many technological products, illustrated in figure 2, would not function well; batteries would be less durable and energy efficient, magnets would be less strong and catalyst would be less efficient.

figure 2: Application of REE/Ms within modern technologies. Source: Civilsdaily.com, (2018) The production and inventions of products containing REE/Ms has increased over the last decades, and as a result, the demand for REE/Ms has developed significantly (figure 3). Considering the rapid development of green technologies in regard of the predicted counter measures against climate change (e.g. batteries and electric motors) the demand for REE/Ms will rise even more (Boer & Lammers, 2013).

(9)

Figure 3: Supply and demand of REEs (2005-2015) (ROW = rest of world). Source: Boer and Lammers, 2013

Although most REE/Ms are relatively abundant in the earth crust, they do not often occur in large concentrated exploitable ore deposits (Liu and Bongaerts, 2014). As a result, there are not many locations on earth where REE/Ms are extracted profitably. The main extraction locations are found in China, which extracted more than 75% of the total production in 2017 (figure 4;Haque et al., 2014, King, 2019). The main profitable ores which contain REE/Ms are bastnaesite, monazite, and loparite and the lateritic ion-adsorption clays (Liu and Bongaerts, 2014). The procedure to extract the REE/Ms from the parent material is energy demanding due to multiple complicated (chemical) procedures. With a higher demand for products containing these REE/Ms, the energy consumed and needed to extract these non-renewable metals is rising (Vidal et al, 2013). Therefore, the impact of the production of REE/M containing products on resources and global change is rising.

(10)

figure 4: Extraction of REEs in the last decades. Source: King (2019), Geology.com.

Due to the growing demand and usage of REE/Ms the European Commission already stated the future availability of several REE/Ms is in critical condition (Boer and Lammers, 2013). As the Netherlands does not have the geological environment to extract these REE/Ms itself from natural resources, it will be depended on other REE/Ms extracting countries for the necessary supply.

Nevertheless, one way to retrieve REE/Ms in the Netherlands could be UM. To determine the necessity of UM it is important to know how the future availability of certain elements will develop. If future scarcity will affect Amsterdam, then UM could be a solution in a circular economy.

Circular economy

Reusing REE/Ms in UM is a possibility in a circular economy in the Netherlands. UM has many potential benefits; including the ability to be a both regenerative and lucrative initiative. It is mainly for this reason that UM is a distinct enterprise in circular economy.

This paragraph will explore the concept circular economy by its origin, distinct characteristics and current implementation. Circular economy is a concept widely debated in the scientific field. It is ambiguous mostly not for its meaning, but for its representation. The term has had several pursuances including bioeconomy, green economy and circular economy; used interchangeably depending on the field or situation (D’Amato, 2017). The concept really gained footing in 1970 when the MacArthur Foundation established a platform to promote circular economy and its initiatives (MacArthur, 2013). Their definition distinguished the term from its equivalents by emphasizing the importance of maximising utility value in the recycling and reusing of materials and products. This resulted in a better validated and established representation of the term, allowing researcher to further explore the concept. Murray et al., (2017) stressed the importance of planning in circular economy, while

(11)

Kirchherr et al., (2017) established the importance of business models and different scale levels. To date over 140 definitions of circular economy exist, yet almost all are based on the same 4 principals: 1) Reduction, reusing, recycling and recovering of materials is crucial. 2) This is realised in consumption, production and distribution processes. 3) Accomplishing economic growth, environmental quality and social equity are equal goals. 4) Its ultimate goal is to establish a sustainable economic model for the future. The goals constituting the essences of circular economy are ambitious, sometimes deemed unachievable; therefore, rendering critique from many academics. D’alisa et al. (2015) critiques the idea of continuous economic growth, stating that even with recycling, the deterioration of materials over time will still call for the necessity of the further depletion of REE/Ms; thus, undermining environmental stability.

The goal to make Amsterdam completely circular, is attempted to be realised through the so-called donut model (Raworth, 2013). This model implies that there is a lower and upper limit to welfare. In order for people to live a socially just existence, without crossing planetary boundaries, humanity must aim to bring related variable in between these limits (Gemeente Amsterdam, 2019). Circular economy, although critiqued, does aim for a better tomorrow. It tries to change a dominant system, not just through literature, but also through initiatives. One of these initiatives is UM. It operates in a city, which Savini (2019) describes as “networks of material streams, in which one activity’s waste becomes another's resource”; a perfectly fitting definition for UM to operate in. The challenge for UM is to be able to draw from these waste streams; this has to be made logistically possible by involvement from municipalities, local parties and initiatives and sometimes even national government. However, keeping D’alisa’s critique in mind, Savini (2019) states that cities should focus on limiting the consumption of materials just as much as recycling them. Therefore, policy should be more aggressively addressing consumption if social and environmental quality within circular economy is to be safeguarded (Fitch-Roy, 2019).

(12)

Policy making

There are four methods that can help policy making in managing e-waste, by examining the environmental consequences of UM (Kiddee et al., 2013). First, there is the Life Cycle Assessment (LCA). In this method, a LCA looks at the impact on the environment of a product given a set of factors. Here, the product’s life cycle is being assessed from the material acquisition to the waste management (Finnveden et al., 2009). These results can be taken into account when solving the problem in policy making, because information and environmental aspects of different systems is needed to meet the challenges of environmental threats like climate change (Finnveden et al., 2009). By using this assessment in practice, waste gets reduced in the process of production. This is advantageous for the production process in the circular economy. Moreover, part of the phase of waste management is the disposal and recycling, in which UM falls (Finnveden et al., 2009).

Second, there is the Material Flow Analysis (MFA). This researches the traveled distance from the starting point to the end point of e-waste (Kidee et al., 2013). The informal recycling of many electronics occurs in developing countries, which has been a eyesore for NGOs and governments (Kahhat & Williams, 2012). At the national level, some countries have put restrictions on the import and export of e-waste or scrap electronics. However, enforcing these restrictions has proven to be difficult (Kahhat & Williams, 2012). This analysis looks at primary data from public and business sectors, and secondary data for available recycling and landfill studies. Therefore, doing a MFA can address this challenge of environmental impact and make proper policies in e-waste.

Third, there is the Multi Criteria Analysis (MCA). This analysis determines the trade-offs between environmental and economic benefits (Kiddee et al., 2013). This is a useful approach because social and environmental effects are being taken into account, as well as the hierarchical level of decision making (Nijkamp & van Delft, 1977). A couple of reasons why MCA is a useful approach according to Nijkamp and van Delft (1977) are that societal benefits of implementations are needed to be taken into account, governments and other public decision makers should focus on the complete societal well-being, alternative plans need to be tested to view whose situation gets better or worse with implementing decisions, and evaluation methods needs to agree with planning processes before implementing.

(13)

Lastly, there is the Extended Producer Responsibility (EPR). This approach discerns the actors responsible for taking back used products containing electronic and electrical material. The polluters have to pay, in order to retrieve environmental equality (Kiddee et al., 2013). This approach in which product take-back is based on, is a political approach in treating end-of-life products. There are already existing laws in retrieving products to reduce environmental impacts and avoiding these hazardous materials to end up in waste streams. Nevertheless, the addition of new approaches provides an incentives to design products that are easy to recover, this approach is described in the Waste Electrical and Electronic Equipment Directive (WEEE) by the European Commission (Atasu & Subramanian, 2012).

With these methods, the different stakeholders in the Netherlands and Amsterdam which are partaking in the UM initiative will be analyzed to see the opportunities for implementing UM. The main policy in the Netherlands for the retrieval of e-waste is called ‘Waste Electric and Electronic Equipment LABel of EXcellence’ (WEEELABEX). This is a policy in which implementations for collecting e-waste safely in order to maintain human health are conducted by acknowledged recycling companies (Vereniging NVPM, n.d.). Specifically, for UM, Metabolic, an organization focusing on sustainable challenges and the transition to a circular economy, collaborates with different institutions to implement a project called: ‘Prospecting the Urban Mines of Amsterdam’ (PUMA). They conducted a research regarding UM in Amsterdam and are now in collaboration with New Horizon, a new partner in UM in Amsterdam, to collect e-waste from buildings (Baars, n.d.), with the acknowledgement of WEEELABEX.

Effective siting of waste treatment facilities and landfills

Closing the loop of the life cycles of materials through the recovery of said materials from urban waste streams is the integral component of UM (Mining, 2015). To achieve this, facilities that can process the recovered REE/Ms are required. Furthermore, as not all materials in the anthropogenic stock are viable for recovery, a landfill is needed to safely storage this surplus (Krook & Baas, 2013). Criteria for the siting process of the waste treatment facility (WTF) and landfill are discussed below.

Because of the risks associated with processing waste in the proximity of a populace, adequate siting of the landfill is paramount (Carabain, 2012). There have been multiple case studies that employed different criteria during sitting processes. When reviewing these case studies multiple criteria can be distilled that could prove fruitful when applied to the Amsterdam metropole. These practical criteria include: The sites should be; 200m away from (rail)roads, 500m away from water bodies, 2000m away from populated land, above the water table and on an impermeable layer (de Waele et al., 2004).

(14)

Another important consideration is the siting of a WTF that will be involved in the process of recovering REE/Ms (Scharff et al., 2011). During siting processes there are multiple planning considerations that should be kept in mind. Firstly, during the decision-making process the Best Practical Environmental Option (BPEO) should be chosen. The BPEO can be defined as a procedure that establishes, for a certain objective (in this case the siting of a WTF), the best option that causes the least damage to the environment. (Office of the Deputy Prime Minister, 2004). Secondly, the majority of the waste should be treated in the region where it is generated, the so-called proximity principle (Brunner, 2011). Currently, the EU does not provide specifics on how large this proximity area is, e.g. “Wastes should be disposed of as close to the source as possible.” and “The Proximity Principle highlights a need to treat and/or dispose of wastes in reasonable proximity to their point of generation.” (European Commission, 2014 & Portal Planning (n.d.)) Lastly, externalities that affect nearby communities should be considered, as these communities could adopt a ‘not in my backyard’ demeanor (Hirschhorn, 1984). To avoid this, a social impact assessment should be executed which is defined as: “the systematic advanced appraisal of the impacts on the day-to-day quality of life of persons and communities” (Burdge, 1987). A list of associated variables can be found in appendix 1.

Additionally, to these criteria, Minehart & Neeman (2002) propose an auction-like process, called the Vickrey auction. This entails that all municipal districts in the targeted area are obligated to table a ‘bid’ that represents the disutility that their community would experience due to the construction of a WTF and/or landfill. It is assumed that the construction costs are known. The district with the lowest bid + cost figure is chosen to facilitate the building of the WTF and/or landfill. The other municipal districts pay, proportionally to their size, transfer payments to the losing district.

When combined, the above-mentioned concepts constitute a new siting procedure for Amsterdam. This involves that first viable districts have to be selected that match the criteria, i.e.. proximity principle and BPEO. The remaining districts have to participate in a Vickrey auction. However, this siting procedure will include the costs, discerned by the social impact assessment, into the equation, attempting to represent the costs for communities associated with the construction of a WTF. At the end of the trajectory a district will have been chosen that has to construct the WTF. The same framework can also be applied when siting a landfill, only the initial criteria differ. The location must be:n2000m away from populated land, 500m away from water bodies, 200m away from (rail)roads, on an impermeable layer and above the water table

It must be kept in mind that the siting criteria and concepts are distilled from policy documents and research that was aimed at different cities. During the literature review, the criteria and theories were assessed on their suitability for the case study, however it cannot be guaranteed that the proposed siting process will be effective. The siting process must be critically examined and tested, before it can be employed.

(15)

Problem definition

As mentioned in the introduction the research will focus on the possibilities of integrating an UM structure into the municipality of Amsterdam. Graedel (2011) argues that the concept of UM is still in its infancy. Therefore, the knowledge base is still marginal and can be improved on (Brunner, 2011). A common critique is that the knowledge is almost solely theoretical, illustrating the need for applicable frameworks (Krook & Baas, 2013). The research will attempt to bridge this knowledge-gap by integrating the theories, described in the theoretical framework, into a framework/method to analyze UM in relation to Amsterdam. This leads to the following research question: “What are the opportunities for the Urban Mining of Rare Earth Elements and Metals (REE/M) in the city of Amsterdam?”. To adequately answer this question, it is necessary to establish the urgency of the implementation of UM into the Amsterdam metropole, the question adherent to this is: “What is the urgency of integrating Urban Mining of REE/M in Amsterdam?”. The integration process of such a novel concept is bound to encounter hiccups on the way. Possible complications have to be brought to the table, to have the possibility the prevent them, therefore: “What are the possible complications with integrating Urban Mining in Amsterdam?”. Moreover, it is not economically viable the extract all the different elements and metals from the anthropogenic stock (Liu and Bongaerts, 2014). Discerning which elements and metals are cost-effective when mined is therefore important: “What materials in the urban waste streams are viable for Urban Mining?” lastly, when push comes to the shove the capitalist creed of today’s society commands that a new and promising concept should eventually be profitable. Hence, an analysis on economic optimization and cost estimation is needed to scrutinize this requirement: “What economic theories can be used to increase the monetary viability of Urban Mining in Amsterdam ?”.

Yet, findings may contradict the agenda and approach of the municipality. Amsterdam’s circular strategy for 2020-2025 aims to initiate a shift to a full circular city by 2050 (Amsterdam Circulair, 2020). However, it is aimed to realize this by the purchasing of circular products and resources (Innovatie- en Uitvoeringsprogramma 2020-2021, 2020). Hereby, they shift the burden to the producer, rather than the user. This fundamentally contradicts the intention of Urban Mining, which manages products discarded by users. The complexity of the problem thus exceeds knowledge gaps and implantation predicaments; it is a disagreement with actors on a rudimental basis which calls for an interdisciplinary approach.

(16)

Interdisciplinary integration

When employed separately, the theories and concepts mentioned in the theoretical framework, prove insufficient to comprehensively analyze the possibilities of Urban Mining within the Amsterdam metropole. However, integrating the different theories could potentially yield a fruitful novel framework that does allow for the desired interdisciplinary analysis (Taekema & Klink, 2009). This integrative framework can be interpreted as a process that along the way discerns the possibilities and complications.

Using the four methods of Kiddee et al. (2013) the different disciplines come together in analyzing the opportunities for UM in Amsterdam. First, the LCA will be used for the Earth Science discipline to examine the environmental impact of a product. Alternatives in production can be examined, in this case UM. Second, the MFA is a way in which the negative environmental impacts of REE/Ms can be shown. This method will not extendedly be used in the analysis and results, but it does show the relevance of changing the current trends in waste. Thereby, it is a relevant method to show how UM could have potential in a circular economy. Third, the MCA will be used to find possible locations for UM in Amsterdam by Urban Planning and Earth Science. This will be of geographical relevance that is important in the Social Geography discipline as well. The economic aspects will be outlined here as well, which makes this analysis an interdisciplinary method in this report. Last, the EPR will be used to examine which actors are responsible for the different aspects in the process of UM.

(17)

Methodology

Although UM is a relatively new concept, there are already multiple regions that have, partly, integrated an UM system. A multitude of research has already been conducted and although this research is quite abstract circumstantial, i.e. most studies are focussed on the regions where it already has been integrated in the respective waste management structure, the insights from these studies could be extrapolated and used for this report. As mentioned above, the four methods described by Kiddee et al. (2013), are used to weave the theories and concepts together, which allows for a comprehensive analysis of the possibilities of UM within the Amsterdam metropole. To research the urgency of integrating UM in Amsterdam a LCA will be employed. The corresponding factors on which the LCA is based are:Primary energy, GHG, water consumption, toxicity.When applied, these tools can disclose the routes that waste streams take and discern the different environmental impacts of the anthropogenic stock. The data needed for this analysis will be extracted from commenced studies on the subject. The possible complications with the integration of UM in Amsterdam will be explored by an MCA and an EPR using secondary data. The MCA, which in this particular case is interchangeably with the siting process for a WTF and landfill, the criteria/factors for this siting process are as follows: the site must be 2000m away from populated land, 500m away from water bodies, 200m away from (rail)roads, on an impermeable layer and above the water table. Furthermore, according to the proximity principle both the WTf and landfill must be located within the Amsterdam metropole (Brunner, 2011). During this siting process possible bumps on the roads can occur, e.g. the concrete siting criteria clash with the social impact assessment or according to the economic viability theories the chosen site is financially not feasible. The EPR can discern possible conflicts between concerned and/or affected parties and appoint financial responsibilities for polluting parties. The UM structure has three stages where pollution may occur: Extraction, transportation and storage. Furthermore, an attempt will be made to distinguish locations that satisfy the site criteria, by employing the ArcGIS software. This will however be a rough estimation, as this study does not have access to the required data sets and maps, e.g. water permeability maps/data and railroads maps/data. Consequently, the site locations will be discerned through a close examination of the map within ArcGIS. The uncertainty concerning the site locations must be kept in mind. The MCA will be used to determine which materials are viable for UM. These analyses can determine how waste deteriorates over time and therefore can decide which anthropogenic stock is viable for UM. To establish the costs and benefits for the city of Amsterdam a second EPR and MCA will be employed. The EPR will be based on the costs and benefits of UM in the waste management of, in particular, e-waste. The MCA will be based on the economic viability theories which will attempt to value the cost estimation and

(18)

economic optimization by employing the factor method. The corresponding criteria for this factor method are: Operational costs, accounting costs, gate fee and capital costs.

(19)

Results

The Urgency of Urban Mining in Amsterdam

As shown before, with the growing demand for production and consumption, due to the growing world population, retrieving REE/Ms in alternative ways has become increasingly more important. First of all, REE/Ms are being collected separately from other kinds of waste and recycled because of four reasons according to WEEE. The reasons for treating e-waste differently are: 1) The materials in e-waste are being recycled or stored safe and efficiënt, this are the REE/Ms in this study. 2) By recycling these, usable materials can be used again and decreases the necessity for new production. 3) Harmful substances are being removed safely so that it does not affect the environment. 4) Responsible recycling makes sure the materials do not go to developing countries where there are no rules for health- and environmental circumstances. These reasons are based on the Convention of Basel that many countries have signed in 1989 which stimulates countries to process waste environmental friendly. The legal framework for the collection and recycling of e-waste is the European WEEE; Waste of Electrical and Electronical Equipment (WEEE Nederland, 2015). This policy is set up to recycle the toxic e-waste in a safe and organized manner. In order not to risk human health, a number of organizations and companies are acknowledged to recycle this e-waste, or burn it. This affects UM, because it makes it difficult for companies or organizations to implement UM that are not acknowledged to recycle e-waste.

Under the Vereniging NVMP, an organization specialized in retrieving and recycling of e-waste, the organization Wecycle collects and separates around 40 percent of the discarded devices and lamps which are handed in at stores, municipalities and other collectors. Wecycle contracts different companies to sort, transport and recycle this e-waste. With this, Wecycle saves 449.000 tonne of emissions of CO2. The NVMP association supports efforts to combat exports from the Netherlands to developing countries and offers an alternative to the primitive processing of e-waste (Vereniging NVMP, 2018). Wecycle looks, with the policy of “polluters have to pay”, at the impact of people or companies in order to reduce e-waste at their end. Also, being rewarded when e-waste is handed in, is such a policy where people hand in the e-waste for free with the quote “handing in is getting back”. Wecycle uses the e-waste to make new products. They promote handing in with giving the e-waste a new beginning in the circular economy (Wecycle, 2020). Next, besides the actors in e-waste, there are actors involved especially with UM in the Netherlands and Amsterdam. The biggest actor here is Metabolic with the PUMA plan; Prospecting the Urban Mines of Amsterdam, which aims at increasing the potential of harvesting the REE/Ms residing in the waste streams in the city of

(20)

Amsterdam. This organization did not realize the UM in Amsterdam, but they did, so they say, provide more insights and made a step towards implementation (Blok, 2020).

The general consensus of implementing an UM facility is to compare the benefits of an UM facility to the negative externalities of an UM facility on the environment. An important tool for this is the Life Cycle Assessment (LCA). This tool will measure the overall environmental impact of a certain product. The LCA could help to make a legitimate decision.

The LCA of several REE/Ms is calculated by Haque (2014) (table 1). The amount of energy and water used differs between the analysed REE/Ms. Nevertheless, the energy and water used to produce the REE/Ms is high, considering that the data is calculated for 1 kilogram of REE/M. Furthermore, the production causes toxicity which is measured in disability adjusted life year. This can be seen as a measurement of the gap between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability. The different stages and chemicals used by the extraction of primary mining is the main reason for the high carbon footprint (figure 5).

(21)

Figure 5: Total carbon footprint of different REE at different stages. Source: Haque et al., 2014 Table 2: Benefits of recycling on the LCA of different metals. Source: Xue, 2018

With recycling the LCA of certain metals could be lowered (table 2). From the table of Xue (2018), it becomes apparent that recycling of metals could have a great impact on the lowering of emissions and waste products. Recycling influences the LCA of a metal significantly. Metals are produced in a similar way as REE/Ms and therefore table 1 could give a first impression on the effects of recycling REE/Ms. However, due to higher concentrations of metal in metal ores, the production of metals is more efficient than the production of REE/Ms. As earlier mentioned, the concentration of REE/Ms in ores is very low. The concentration REE/Ms is much higher in the recyclables. Thus, with the same amount of energy and chemicals, one can extract more REE/Ms from the recyclables than from primary mining. However, there is still a lot of disposable waste produced, which need to be handled at a local level. As mentioned earlier, REE/Ms are a relatively new element in many products and as a result, there are not many companies yet that focus on their recycling. Little is known about

(22)

the processes these companies use (Zaimes, 2015) and therefore quantitative data about the impact of recycling REE/Ms is still lacking.

Locally, the environment could be negatively influenced due to the emissions and waste produced by the UM, however, the global impact of an UM will be positive. The decision, about which is more important lies with the stakeholders, and will determine if the UM facility will be installed, despite the potential effects locally.

The Complications for Amsterdam

An integral component of UM is the decision-making process for the site location of a WTF and Landfill (Krook & Baas, 2013). In the theoretical framework and methodology multiple criteria were described for the siting of a WTF and landfill which would safeguard the surrounding area from environmental deterioration. With these criteria in mind an attempt was made to locate sites that meet these rather stringent criteria using ArcGIS software (Figure 6).

(23)

Figure 6: Potential UM locations within the Amsterdam metropole

After a careful examination, multiple potential sites were located (figure 6). Looking at these locations one can already perceive that the sites do not meet all the requirements, which mainly due to the fact Amsterdam metropole is a heavily populated region. If however, some leniency is granted, the siting process could advance to the next step, i.e. the altered Vickrey auction. The city districts that encompass a potential UM site have to participate in the auction, to designate which district has to

(24)

construct the WTF and/or landfill. Again however, a complication arises, when the governing system can not oblige the districts to participate in the Vickrey auction (Minehart & Neeman, 2002).

The EPR method will list the actors involved in UM and in recycling e-waste. According to this method, the polluters have to pay. This method could be used in order to come to a financial agreement when implementing UM. This method is used by OECD, the Organization for Economic Cooperation and Development, which is a joint venture of 37 countries to discuss social and economic policies. Producers get the financial and physical responsibility for the treatment and disposal of used products (Smith, 2005). This method is set up to reduce waste at the source and to promote innovation designs for the environment. An outcome from this evaluation was that the communication with stakeholders and the public could be improved on. This will be elaborated on for the financial feasibility further on.

Looking at the impact of the Urban Mining plant on the environment. An UM plant which deals with certain REE/Ms will have an effect on the environment. This is important to note, to clearly investigate the effect of an UM plant on the environment and if this is acceptable, in comparison with the primary production of REE/Ms. The UM facility has multiple stages where it is possible to generate pollution in various ways. These stages are transportation, storage and extraction:

Transportation of waste could cause extra pollution, mainly in the form of extra energy and CO2emission (Xue, 2018). When applied to Amsterdam, the UM needs to mainly create an input of e-waste from their direct surrounding agglomerates to reduce the amount of energy wasted and lower the amount of CO2emissions. Another solution is to only use vehicles that do not have CO2emission.

Storage of e-waste is a more difficult subject. The input of e-waste created by the municipality of Amsterdam needs to be temporarily stored before it can be processed. Certain REE/Ms are a risk for the environment. By creating landfills with e-waste, some REE/Ms can contaminate the soils or the water, eventually ending in the groundwater. As earlier mentioned, this could affect the health of not only the environment, but also for humans (Chakraborty et al., 2016). Thus, the stock pilling and creation of a landfill is required, according to the siting criteria mentioned in the theoretical framework and methodology.

The extraction of REE/Ms is difficult, as many procedures to extract these REE/Ms are similar as the procedures used in virgin mining (Tunsu, 2015). For many REE/Ms there is a pre-processing part whereby e-waste is being crushed to create a bigger surface. This is done to improve the efficiency of the second part, the hydrometallurgy. This is a process which includes strong acids and the use of large amounts of toxic, corrosive and flammable reagents (Isildar et al, 2018). Furthermore, it generates high volumes of effluents and other solid wastes (Isildar et al, 2018). This imposes further problems and threats to the environment which needs to be considered when implementing an UM facility. Another option is biohydrometallurgy, this method has lower leaching

(25)

rates and is slower. However, this method is better for the environment and more cost-effective (Ilyas and Lee, 2015).

Viable REE/Ms for Urban Mining

To be less dependent of future fluctuations in availability and price, one need to estimate which REE/Ms are viable to extract through UM. The Netherlands does not have the geological structures to be self-sufficient in REE/Ms and therefore is largely depended on other countries for their demand in REE/Ms. Due to a growth in the demand of REE/Ms, which is prospected to growth even further, the availability of REE/Ms to support global demand could be a problem. Furthermore, Amsterdam has the ambition to be a sustainable city with a circular economy. One of the aims is to re-use as much materials as possible. This, to be less dependent and to lower the pressure on the environment, not only locally, but also globally. The question of which REE/Ms are viable for UM is therefore already answered. All REE/Ms are important to extract through UM to achieve the goal of Amsterdam to be a circular economy.

The Financial feasibility of Urban Mining

The city of Amsterdam is currently initiating a transition to a city functioning on circularity (Amsterdam Circulair, 2020). One may expect major investments by the municipality in initiatives realizing the reuse and recycling of products and materials in order to achieve the circularity goals. However, these investments remain marginal, for they are focussed on spreading awareness and knowledge of recycling and reusing products to citizens (Innovatie- en Uitvoeringsprogramma 2020-2021, 2020) instead of implementing it in a broader spectrum. This is a cost-effective approach but may deem to be less successful in the realization of a circular city in the future. Therefore, cost estimation and economic optimization have been looked at to estimate the economic impact of visible and measurable initiatives surrounding circularity. When looking at Urban Mining, both a cost estimation and economic optimization can be estimated. By employing the factor method (Murphy & McKeogh, 2004; Zeng et al., 2018), operational cost, accounting cost, gate fee and capital cost are looked at. This is done in comparison to the current approach of the municipality; which aims to increase circularity by purchasing circular resources and products (Amsterdam Circulair, 2020). Urban Mining is comparatively fundamentally more expensive. However, the purchasing of resources is not a business strategy and has no potential to become a lucrative enterprise. This is different for UM. An economic optimization is dependent on optimization techniques. Satter & Iqbal (2015) formulate 5 aspects: 1) setting an economic objective, 2) formulating a scenario, 3) data collection, 4) an economic analysis, 5) optimization of production or operation. It is expected that UM will use

(26)

techniques regarding the calculation of the input-output of REE/Ms (Ataee-Pour, 2005) to optimize production. This optimization of production will most likely result in a higher output of product, thus increasing revenue. Additionally, Zeng et al., (2018) state that the urban mining of some e-waste metals is more profitable than virgin mining of REE/Ms. Thus, UM has the potential to be a lucrative enterprise. However, Murphy & McKeogh (2004) discuss cost factors in WTF’s and conclude that capital cost (one-time expenses, made to set up a business, such as the purchasing of fundamental equipment) for UM is high, and as gate fees are paid per disposed kg or ton waste, they remain a continuous expense. And thus, a higher input of waste is incapable of generating substantially higher revenue, only an in increase in efficiency of processing these materials is.

The OECD wrote an article in which the costs and benefits were being evaluated in an EPR approach. In the article three designs where given to be applied. These are: 1) “obligations on the producer concerning the collection (“take-back”) of product packaging or end-of-life products.” 2) “producers bearing financial responsibility for the costs of proper waste management of the collected products and materials.” 3) “rules or targets governing the methods of waste management of recovered products, for example specifying minimum required rates of re-use or recycling.” (Smith, 2005). These three designs could be used for UM due to the fact that this EPR method is an approach of waste management, in which UM could be a possibility. The third design is in a way already been implemented in the Netherlands, that is the WEEELABEX. The first two designs are allocating the responsibility towards the producers of the polluting materials. This obligates the producers to recycle retrieve and recycle the products they introduced into the consumer market . In this way, the producers pay for the UM to reduce the waste.

(27)

Conclusion

Regarding the urgency of UM for the city of Amsterdam multiple stakeholders agree that the current production of REE/Ms has a significant negative impact on the environment and therefore support the introduction of UM. This is also supported by the executed LCA, as it is remarked that, the integration of UM can have a positive effect on the environment. However, meeting the siting criteria for a WTF and landfill is complicated, since Amsterdam has a considerable population density. Moreover, the EPR analysis concluded that clear and transparent communication between stakeholders with the public concerning UM, must be a point of attention as well as the importance of placing responsibility; polluters have to pay. Lastly, the potential negative impact of a WTF or landfill on its direct surroundings must be noted, as possible complications could arise. As for the REE/Ms that are viable for extraction, the simple answer can be given that they are all viable. And concerning the last subquestion, the financial feasibility of UM for the city of Amsterdam is rather ambiguous since the introduction of UM is rather expensive in short term, however some studies have indicated that the financial viability of UM could potentially in the long term be optimized, there is still however much uncertainty surrounding this.

Thus, at the moment there are still a multitude of complications and uncertainties regarding the implementation of UM into the Amsterdam metropole. Hence, the careful conclusion can be made that at this point in time the feasibility of integrating UM into the existing waste management structure of Amsterdam are slim. If the municipality wishes to increase the possibilities for UM in Amsterdam, this research recommends an expansion of the search area for possible locations for a WTF and landfill by employing a more lenient interpretation of the proximity principle, as this currently constitutes the biggest roadblock for the implementation of UM.

Discussion

Due to the complex nature of an UM structure, an interdisciplinary approach was chosen to analyze the possibilities of UM for the city of Amsterdam. This research employed four different disciplines: Human geography, economy, geology and urban planning. However, UM is located at the interface of more disciplines, e.g. engineering, political science and chemistry. Thus, further interdisciplinary research employing different and overlapping disciplines, e.g. engineering majors can focus construction of a WTF, from the political science discipline, possible conflicts between different jurisdictions areas regarding the siting of a WTF can be discerned and from a chemistry/biology perspective potential environmental dangers can be distinguished.

Moreover, This study is part of a rather small collection of reports and studies on the possibilities of UM for the Amsterdam metropole and is mainly based on insights from other regions

(28)

where UM is being implemented. Thus, this report must be regarded as a stepping stone for future research in this particular field of study. During the research multiple knowledge gaps became apparent that are related the siting process, the uncertainty of the financial feasibility and the EPR method. Our recommendations for future studies are aimed to bridge these gaps:

- A detailed and thorough examination of possible WTF and landfill sites employing ArcGIS software. This study did not have access to data regarding populations spread, railway stracks and the permeability of the land.

- Currently specifics on the long term financial viability are not known. An analysis regarding this knowledge gap could significantly help new studies.

- Evaluating the effects of the EPR method for UM cannot be done immediately, so time will tell if this approach could be successful. However, when the EPR method is already being used in another country, that assessment can be applied to other countries and other categories of waste. Countries from the OECD have already implemented EPR programmes, so assessing e-waste in the Netherlands, and particularly Amsterdam, should be possible.

Bibliography

Arora, R., Paterok, K., Banerjee, A., & Saluja, M. S. (2017). Potential and relevance of urban mining in the context of sustainable cities. IIMB management review, 29(3), 210-224.

Ataee-Pour, M. (2005). A critical survey of the existing stope layout optimization techniques. Journal of Mining

Science, 41(5), 447-466.

Atasu, A., & Subramanian, R. (2012). Extended producer responsibility for e‐waste: Individual or collective producer responsibility?. Production and Operations Management, 21(6), 1042-1059.

Baars, M. (n.d.). New Horizon. Retrieved April 17, 2020, from https://newhorizon.nl/urban-mining/

Blok, M. (2020). Prospecting the Urban Mines of Amsterdam. Metabolic. Retrieved April 2, 2020, from https://www.metabolic.nl/projects/prospecting-the-urban-mines-of-amsterdam-puma/

Boulton, J., & Allen, P. (2007). The complexity perspective. In V. Ambrosini, M. Jenkins, & N. Mowbray (Eds.), Advanced strategic management: A multi-perspective approach (2 ed.). Palgrave Macmillan

(29)

Brunner, P. H. (2011). Urban mining a contribution to reindustrializing the city. Journal of Industrial Ecology,

15(3), 339-341.

Carabain, C., Spitz, G., & Keulemans, S. (2012). Nederlanders & afval: Jonge en oudere Nederlanders over

afval.

Chakhmouradian, A. R., & Wall, F. (2012). Rare earth elements: minerals, mines, magnets (and more).

Elements, 8(5), 333-340.

Chakraborty, P., Selvaraj, S., Nakamura, M., Prithiviraj, B., Ko, S., & Loganathan, B. G. (2016). E-waste and associated environmental contamination in the Asia/Pacific region (Part 1): an overview. In Persistent Organic Chemicals in the Environment: Status and Trends in the Pacific Basin Countries I Contamination Status (pp. 127-138). American Chemical Society.

Civilsdaily. (2018, 14 december). Rare Earth Elements. Geraadpleegd op 29 mei 2020, van https://www.civilsdaily.com/rare-earth-elements/

Closing the Loop. (n.d.). Closing the Loop. Retrieved May 14, 2020, from https://www.closingtheloop.eu/our-services

D'Amato, D., Droste, N., Allen, B., Kettunen, M., Lähtinen, K., Korhonen, J., ... & Toppinen, A. (2017). Green, circular, bio economy: A comparative analysis of sustainability avenues. Journal of Cleaner Production, 168, 716-734.

De Boer, M. A., & Lammertsma, K. (2013). Scarcity of rare earth elements. ChemSusChem, 6(11), 2045-2055. De Waele, J., Nyambe, I. A., Di Gregorio, A., Di Gregorio, F., Simasiku, S., Follesa, R., & Nkemba, S. (2004). Urban waste landfill planning and karstic groundwater resources in developing countries: the example of Lusaka (Zambia). Journal of African Earth Sciences, 39(3-5), 501-508.

Dodson, J. R., Hunt, A. J., Parker, H. L., Yang, Y., & Clark, J. H. (2012). Elemental sustainability: Towards the total recovery of scarce metals. Chemical Engineering and Processing: Process Intensification, 51, 69-78.

European Commission. (2014). WASTE MANAGEMENT LEGISLATION. Retrieved may 28, 2020, from https://ec.europa.eu/environment/archives/enlarg/pdf/handbook/handbook.htm

(30)

Finnveden, G., Hauschild, M. Z., Ekvall, T., Guinée, J., Heijungs, R., Hellweg, S., ... & Suh, S. (2009). Recent developments in life cycle assessment. Journal of environmental management, 91(1), 1-21.

Fitch-Roy, O., Benson, D., & Monciardini, D. (2019). Going around in circles? Conceptual recycling, patching and policy layering in the EU circular economy package. Environmental Politics, 1-21.

Geissdoerfer, M., Savaget, P., Bocken, N. M., & Hultink, E. J. (2017). The Circular Economy–A new sustainability paradigm?. Journal of cleaner production, 143, 757-768.

Gemeente Amsterdam. (2020). Innovatie- en Uitvoeringsprogramma 2020-2021. Retrieved May 6, 2020, from https://www.amsterdam.nl/bestuur-organisatie/volg-beleid/ambities/gezonde-duurzame-stad/amsterdam-circulair -2020-2025/

Gemeente Amsterdam. (2020). Amsterdam circulair 2020-2025 Strategie. Retrieved May 6, 2020, from

https://www.amsterdam.nl/bestuur-organisatie/volg-beleid/ambities/gezonde-duurzame-stad/amsterdam-circulair -2020-2025/

Graedel, T. E. (2011). The Prospects for Urban Mining. BRIDGE, 43.

Haque, N., Hughes, A., Lim, S., & Vernon, C. (2014). Rare earth elements: Overview of mining, mineralogy, uses, sustainability and environmental impact. Resources, 3(4), 614-635.

Hirschhorn, J. S. (1984). Siting hazardous waste facilities. Hazardous waste, 1(3), 423-429.

Humphries, M. (2010). Rare earth elements: the global supply chain. Diane Publishing..

Ilyas, S., & Lee, J. C. (2015). Bioprocessing of electronic scraps. Microbiology for Minerals, Metals, Materials

and the Environment; Abhilash, Pandey, BD, Natrajan, KA, Eds, 307-328.

Işıldar, A., Rene, E. R., van Hullebusch, E. D., & Lens, P. N. (2018). Electronic waste as a secondary source of critical metals: Management and recovery technologies. Resources, Conservation and Recycling, 135, 296-312. Kahhat, R., & Williams, E. (2012). Materials flow analysis of e-waste: Domestic flows and exports of used computers from the United States. Resources, Conservation and Recycling, 67, 67-74.

Kiddee, P., Naidu, R., & Wong, M. H. (2013). Electronic waste management approaches: An overview. Waste

management, 33(5), 1237-1250.

King, H. M. (2019). Rare Earth Elements and their uses. Retrieved 13 March 13, 2020, from https://geology.com/articles/rare-earth-elements/

(31)

Kirchherr, J., Reike, D., & Hekkert, M. (2017). Conceptualizing the circular economy: An analysis of 114 definitions. Resources, conservation and recycling, 127, 221-232.

Krook, J., & Baas, L. (2013). Getting serious about mining the technosphere: a review of recent landfill mining and urban mining research. Journal of Cleaner Production, 55, 1-9.

Lewis, N. S., & Nocera, D. G. (2006). Powering the planet: Chemical challenges in solar energy utilization.

Proceedings of the National Academy of Sciences, 103(43), 15729-15735.

Lieder, M., & Rashid, A. (2016). Towards circular economy implementation: a comprehensive review in context of manufacturing industry. Journal of cleaner production, 115, 36-51

Liu, J., & Bongaerts, J. C. (2014). Mine planning and equipment selection supply chain of rare earth elements (REEs). In Mine Planning and Equipment Selection (pp. 1419-1426). Springer, Cham

MacArthur, E. (2013). Towards the circular economy. Journal of Industrial Ecology, 2, 23-44.

Meadows, D. H., Meadows, D. L., Randers, J., & Behrens, W. W. (1972). The limits to growth. New York, 102, 27.

Menken, S., & Keestra, M. (Eds.). (2016). An introduction to interdisciplinary research: Theory and practice. Amsterdam University Press.

Minehart, D., & Neeman, Z. (2002). Effective siting of waste treatment facilities. Journal of Environmental

Economics and Management, 43(2), 303-324.

Mining, L. (2015). Urban mining: Concepts, terminology, challenges. Waste Management, 45, 1-3.

Murphy, J.D. & McKeogh, E. (2004) Technical, economic and environmental analysis of energy production from municipal solid waste. Renewable Energy, 29, 1043–1057.

Nijkamp, P., & van Delft, A. (1977). Multi-criteria analysis and regional decision-making (Vol. 8). Springer Science & Business Media.

Office of the Deputy Prime Minister. (2004). Planning for Waste Management Facilities.

Portal planning. (n.d.). Planning Policy Statements and Supplementary Planning Guidance. Retrieved 28 May, 2020, from

https://www.planningni.gov.uk/index/policy/planning_statements_and_supplementary_planning_guidance/pps1 1/pps11_introduction/pps11_waste_management_strategy/pps11_the_proximity_principle.htm

(32)

Rare Element Resources. (z.d.). Rare Earth Elements. Geraadpleegd op 29 mei 2020, van http://www.rareelementresources.com/rare-earth-elements#.XtNwmjozZPY

Satter, A., & Iqbal, G. M. (2015). Reservoir engineering: the fundamentals, simulation, and management of

conventional and unconventional recoveries. Gulf Professional Publishing.

Savini, F. (2019). The economy that runs on waste: accumulation in the circular city. Journal of Environmental

Policy & Planning, 21(6), 675-691.

Scharff, H., van Zomeren, A., & van der Sloot, H. A. (2011). Landfill sustainability and aftercare completion criteria. Waste Management & Research, 29(1), 30-40.

Simoni, M., Kuhn, E. P., Morf, L. S., Kuendig, R., & Adam, F. (2015). Urban mining as a contribution to the Fporesource strategy of the Canton of Zurich. Waste management, 45, 10-21.

Smith, S. (2005). Analytical framework for evaluating the costs and benefits of extended producer responsibility programmes.

Taekema, H. S., & van Klink, B. M. J. (2009). Wetenschap-1993 Dwarsverbanden. Interdisciplinair onderzoek in de rechtswetenschap. Nederlands Juristenblad, 84(39), 2559.

Tunsu, C., Petranikova, M., Gergorić, M., Ekberg, C., & Retegan, T. (2015). Reclaiming rare earth elements from end-of-life products: A review of the perspectives for urban mining using hydrometallurgical unit operations. Hydrometallurgy, 156, 239-258

Vereniging NVMP. (2018). Onderzoek, de wereld van e-waste. Retrieved April 2, 2020, from https://www.nvmp.nl/onderzoek/

Vidal, O., Goffé, B., & Arndt, N. (2013). Metals for a low-carbon society. Nature Geoscience, 6(11), 894. Wecycle. (2020). Wecycle. Retrieved May 6, 2020, from https://www.wecycle.nl/

Weee Nederland BV. (2015). Wat is nu eigenlijk e-waste? Retrieved May 6, 2020, from https://weee.nl/nl/kennisbank/e-waste

Xue, Y. (2018). Sustainable urban mining: the case of China. Enschede: University of Twente. https://doi.org/10.3990/1.9789036546294

Yuan, Z., Bi, J., & Moriguichi, Y. (2006). The circular economy: A new development strategy in China. Journal

of Industrial Ecology, 10(1‐2), 4-8.

Zaimes, G. G., Hubler, B. J., Wang, S., & Khanna, V. (2015). Environmental life cycle perspective on rare earth oxide production. ACS Sustainable Chemistry & Engineering, 3(2), 237-244.

(33)

Zeng, X., Mathews, J. A., & Li, J. (2018). Urban mining of e-waste is becoming more cost-effective than virgin mining. Environmental science & technology, 52(8), 4835-4841

Appendix 1 Social impact assessment variables

(34)

Appendix 2

(35)

Opportunities for Urban Mining of Rare Earth Elements in Amsterdam