European National Road Authorities and Circular Economy: An Insight into Their Approaches

sustainability Review European National Road Authorities and Circular Economy: An Insight into Their Approaches Konstantinos Mantalovas 1,* , Gaetano Di Mino 1, Ana Jimenez Del Barco Carrion 2, Elisabeth Keijzer 3, Björn Kalman 4, Tony Parry 5and Davide Lo Presti 1,5,* 1Department of Engineering, University of Palermo, 90128 Palermo, Italy; [email protected] 2Department of Construction Engineering and Engineering Projects, University of Granada, 18003 Granada, Spain; [email protected] 3Netherlands Organization for Applied Scientific Research (TNO), 3584 CB Utrecht, The Netherlands; [email protected] 4Swedish National Road and Transport Research Institute (VTI), 58330 Linkoping, Sweden; [email protected] 5Nottingham Transportation Engineering Centre (NTEC), University of Nottingham, Nottingham NG7 2RD, UK; tony[email protected] *Correspondence: [email protected] (K.M.); [email protected] or [email protected] (D.L.P.); Tel.: +44-746-0705-153 or +39-391-7494-647 (K.M.); +44-758-7140-422 (D.L.P.) Received: 30 July 2020; Accepted: 1 September 2020; Published: 2 September 2020   Abstract: The pavement engineering industry, having realized the significance of the impacts that it imposes on the environment through the production, construction and management of its products and assets, has been driven towards a more sustainable and circular way of operating. This has partly been through asphalt recycling, which is an area that many road authorities have prioritized. However, not all the National Road Authorities (NRAs) and/or sector stakeholders seem to be adequately familiar with the Circular Economy (CE) concept. This paper attempts to assist the transition of NRAs to a more circular way of doing business, by analyzing the current situation of CE within national/regional authorities and NRAs. To do so, a questionnaire was sent to different NRAs and an online search was conducted to identify the ways that NRAs communicate their CE practices. Findings indicate that, although the majority of the NRAs are familiar with CE as a concept, not many actions have been taken so far towards its holistic implementation. Finally, there is a significant lack of CE expertise and communication within these bodies. Keywords: circular economy; asphalt pavements; National Road Authorities; circular procurement; circular recommendations; circular road maps 1. Introduction The debate about future availability of natural resources remains a center of attention. Growing amounts of natural, non-renewable resources are being exploited to fulfil the needs of industries [ 1 , 2 ]. This leads to severe environmental, social, and of course, economic impacts, that disturb the desirable equilibrium between the three pillars of sustainability, as first proposed by Barbier in 1987[ 3 , 4 ]. AccordingtotheRoadmaptoaResourceEfficientEurope(RERM),betterconstructionanduse of built infrastructure could help in achieving significant resource savings: it could influence 42% of our final energy consumption and about 35% of our total greenhouse gas (GHG) emissions, 50% of extracted materials, and it could save up to 30% of water in some regions, when considering the construction industry [ 5 , 6 ]. Since transportation infrastructures—and road pavements in particular—represent one of the largest parts of the built infrastructure, their contribution to energy and water consumption, Sustainability 2020,12, 7160; doi:10.3390/su12177160 www.mdpi.com/journal/sustainability Sustainability 2020,12, 7160 2 of 19 the extraction of virgin materials and the emission of GHGs is significant. A promising concept that has lately re-emerged and pledges to improve the situation and/or relax the pressures on the environment, society and economy, is the concept of Circular Economy (CE). Although there is not a consensual and definitive definition of CE, one of the most widely accepted definitions is that of the Ellen MacArthur Foundation (EMF): “economy that is restorative and regenerative by design, and which aims to keep products, components, and materials at their highest utility and value at all times, distinguishing between technical and biological cycles” [ 7 – 9 ]. Two different types of products can be identified: products that, after their lifecycle, can either return into the technical cycle (durables), or into the biological cycle (consumables) [ 7 , 8 ]. It could potentially provide an answer to increasing resource consumption because it aims to transform the function of resources in an economy [ 10 – 14 ]. This paper, thus, presents the findings of research to answer questions about the familiarity, knowledge, implementation, and communication of Circular Economy by National Road Authorities: •How do NRAs realize their transition to more circular approaches? •How do NRAs implement and communicate their approaches on CE? Within the paper, firstly, in Chapter 2, a brief background of the CE is presented. It revolves around CE, asphalt production and use under the light of CE, and the implementation of circular economy principles in road construction and maintenance. Secondly, in Chapter 3, the methods used for the research are explained distinguishing between three different approaches. The analysis of national/regional authority roadmaps towards CE that have been published through the European CE Stakeholder Platform, the questionnaire about CE and its implementation and completion by National Road Authorities (NRAs) across Europe, and a web search in the official websites of the investigated NRAs in order to identify aspects of communication concerning CE. In Chapter 4, the results obtained and their analysis are presented and finally, in Chapter 5, a brief discussion along with the conclusions of the research conducted can be found. 2. Literature Review 2.1. Circular Economy One of the first publications that successfully managed to raise awareness about the issue of overloadingtheEarth’snaturalsinks(whereecosystemsreceivepollutantsorwastes)andoverexploiting resources, was the report of Meadows et al. (1972), “The Limits to growth”, for the Club of Rome. The broader public was confronted with the thought that only limited growth is possible on a finite planet with finite resources [ 15 ]. The model proposed by Meadows and colleagues studied the interactions between pollution, population, consumption of non-renewable resources, regeneration rates of renewable resources, food, and industrial output. According to their scenarios, system “failure” occurs due to pollution, even though society would have been able to effectively manage to conserve non-renewable resources [ 15 ]. However, Lomborg questioned the objectivity and accuracy of the Meadows model, arguing that human ingenuity and the strength of innovations were not taken into consideration [ 16 ]. A philosophy or concept that encompasses innovation and innovative business models at its’ core, is the Circular Economy. It is a concept that made its first appearance as a proactive policy goal for numerous businesses and in political agendas in the late 1970s, mainly due to climate change and the acute concern of rising resource prices, raised by Carson and Boulding [8,17–20]. Moreover, following this definition, the EMF supports the norm of thinking in systems and cascades. Adopting systemic thinking and a cascade approach, end-products, components and even materials can be repurposed, reutilized, recycled or have their service life extended while keeping their highest value. These principles and their beneficial implementation are analyzed in several publications of the Ellen MacArthur Foundation. Another aspect that is mentioned and also represents a core pillar of CE, is the utilization of renewable resources [ 21 – 24 ]. Moreover, as discussed in the publication of Mark J. Goedkoop et al. from 1999, that was commissioned by the Dutch ministries of Environment (VROM) and Economic Affairs (EZ), the concept of CE is opting to provide a “marketable Sustainability 2020,12, 7160 3 of 19 set of products and services capable of jointly fulfilling a user’s needs” and not just end products, solely to be sold to consumers [ 25 , 26 ]. This concept encompasses the principles of multiple schools of thought, such as “industrial ecology and symbiosis”, “performance economy”, “biomimicry”, “cradle to cradle”, “blue economy”, “regenerative design”, “cleaner production”, and “natural capitalism” [ 27 , 28 ]. Circular economy is a type of economy that integrates principles and approaches originating from all the different types of philosophies/approaches. Some of these proposals date back to 1970 and the constant evolution of different approaches, with a similar end goal, has developed since. CE was first mentioned in 1990 by Pearce and Turner who also modelled it [ 29 ]. The main schools of thought that have contributed to shaping the current philosophy of CE can be seen in Figure 1. Sustainability 2020, 12, x FOR PEER REVIEW 3 of 19 ministries of Environment (VROM) and Economic Affairs (EZ), the concept of CE is opting to provide a “marketable set of products and services capable of jointly fulfilling a user’s needs” and not just end products, solely to be sold to consumers [25,26]. This concept encompasses the principles of multiple schools of thought, such as “industrial ecology and symbiosis”, “performance economy”, “biomimicry”, “cradle to cradle”, “blue economy”, “regenerative design”, “cleaner production”, and “natural capitalism” [27,28]. Circular economy is a type of economy that integrates principles and approaches originating from all the different types of philosophies/approaches. Some of these proposals date back to 1970 and the constant evolution of different approaches, with a similar end goal, has developed since. CE was first mentioned in 1990 by Pearce and Turner who also modelled it [29]. The main schools of thought that have contributed to shaping the current philosophy of CE can be seen in Figure 1. Figure 1. Schools of thought and economic approaches forming the philosophy of Circular Economy (CE). Service Economy is the type of economy in which retailers and manufacturers can maintain the ownership of their products and become “service providers” [30,31]. The Service Economy supports the transition of procurement patterns from product purchasing to service purchasing. The consumer becomes a user, who pays for using a specific product instead of owning it. The term refers to an economic model where the importance is placed on services and the majority of jobs are in service activities. By changing this economic pattern, the service provider not only has an incentive to cut down the resource expenditure but also to reduce the energy consumption in the production process [14,32]. Collaborative Economy is a type of economy that has been decentralized and contains networks of individuals and communities instead of institutions. This type of economy aims to change the way of current production, consumption, finance and education [14,33]. Different expressions that could describe this type of economy are “sharing economy/peer economy” or “collaborative consumption”. In the context of this type of economy, inventors and investors are brought together in order to compile the full procedure of sharing, selecting, producing and distributing new products. Moreover, the utilization of products through redistribution or shared access is a representative paradigm of this type of economy. Thus, the three main aspects of a collaborative economy can be described as [7,14,33] the shift of power away from institutions towards networks of individual actors, the innovative and efficient product utilization, and technological innovation, shifting values, economic realities and environmental pressure being the main drivers. Restorative Economy or “regenerative economy” represents a type of economy that implies the need for creation of a new type of Figure 1. Schools of thought and economic approaches forming the philosophy of Circular Economy (CE). Service Economy is the type of economy in which retailers and manufacturers can maintain the ownership of their products and become “service providers” [ 30 , 31 ]. The Service Economy supports the transition of procurement patterns from product purchasing to service purchasing. The consumer becomes a user, who pays for using a specific product instead of owning it. The term refers to an economic model where the importance is placed on services and the majority of jobs are in service activities. By changing this economic pattern, the service provider not only has an incentive to cut down the resource expenditure but also to reduce the energy consumption in the production process [ 14 , 32 ]. Collaborative Economy is a type of economy that has been decentralized and contains networks of individuals and communities instead of institutions. This type of economy aims to change the way of current production, consumption, finance and education [ 14 , 33 ]. Different expressions that could describe this type of economy are “sharing economy/peer economy” or “collaborative consumption”. In the context of this type of economy, inventors and investors are brought together in order to compile the full procedure of sharing, selecting, producing and distributing new products. Moreover, the utilization of products through redistribution or shared access is a representative paradigm of this type of economy. Thus, the three main aspects of a collaborative economy can be described as [ 7 , 14 , 33 ] the shift of power away from institutions towards networks of individual actors, the innovative and efficient product utilization, and technological innovation, shifting values, economic realities and environmental pressure being the main drivers. Restorative Economy or “regenerative economy” represents a type of economy that implies the need for creation of a new type of relationship between the industrial systems and the ecosystems. This type of economy is able to copy and integrate Sustainability 2020,12, 7160 4 of 19 the mechanisms of nature within the industrial systems in order to restore the natural environment instead of degrading it. Products in the context of this economy should be designed so as to be able to be reused as material inputs to another system’s lifecycle or to be easily deconstructed and reused or maintained with an ultimate goal of increasing biodiversity and not the opposite [ 14 , 34 ]. Other similar approaches that have also been inspired by nature are: “cradle to cradle”, “biomimicry”, “blue economy”, “industrial ecology” and “natural capitalism” [32,35–43]. The CE contains aspects of all three alternative economic models mentioned above. However, the concept distinguishes itself by focusing on the circularity of resources and the avoidance of waste. 2.2. Circular Economy, Asphalt Production and Use So far, common practices that various stakeholders, companies, asphalt contractors and agencies are implementing in line with the principles of CE are the recycling of reclaimed asphalt (RA), the extension of the service life of their assets (preventive maintenance), and the use of wastes in asphalt pavements. The use of RA for the production of asphalt mixtures can lead to positive overall environmental and economic impacts while maintaining an equivalently acceptable technical performance for the asphalt pavements [ 44 ], as previous studies have shown [ 45 , 46 ]. In detail, a mixture that is asphalt-based and incorporates RA contains less bituminous binder and virgin aggregates in comparison to a conventional asphalt mixture. Hence, the environmental impacts are reduced, and the energy demand can be decreased in certain cases by 23%, in comparison to conventional Hot Mix Asphalt mixtures [ 44 , 47 – 50 ]. Asphalt recycling and preventive maintenance though, are sometimes implemented not because they serve the principles of CE and are beneficial in terms of sustainability, but because they are economically beneficial and by the rule of thumb are considered as best practices. Again, nothing has been published in terms of asphalt pavements when it comes to legislative guidelines towards more ‘circular’ pavements. This has not stopped some individual stakeholders moving in this direction. KRATON for example has moved forward by producing SYLVAROAD TM RP1000, a pine chemical additive derived from Crude Tall Oil (CTO), a renewable raw material characterized as a by-product of the paper industry. Its use can increase the levels of RA that can be incorporated into asphalt mixtures, while avoiding significant environmental burdens associated with CO 2 emissions and virgin material utilization [ 8 , 51 ]. Another noteworthy attempt towards more circular products has been made by Tarpaper Recycling, along with Super Asfalt, that have proposed the production of REC100. This is a mobile asphalt plant that allows 100% utilization of the resources in roofing felt and asphalt waste, in order to produce asphalt mixtures incorporating 100% recycled resources. Unfortunately, though, the effort of the pavement engineering industry towards more circular and sustainable products is not yet thriving. As circular economy has been proven to contribute to sustainability [ 52 ], more circular attempts by the pavement engineering industry should be made in this direction if their intention is to become more circular and sustainable. The extension of the application of the CE principles to an asset, such as road pavement, is a rather recent action, particularly within the development of pavement management systems [ 53 ]. Only in recent years has the world of scientific research begun dealing with the issue of the implementation of the CE in the production and treatment processes of asphalt in the road construction industry [ 9 ]. Under the light of CE and for the pavement engineering sector, the recycling of reclaimed asphalt can be characterized as one of the most circular practices. In other words, asphalt recycling is the most common type of recycling that takes place within the road engineering industry [ 8 , 54 ] and can deliver significant environmental and economic benefits. NRAs also incorporate into asphalt pavements other recyclable materials such as steel slag, concrete, glass, etc., but RA is the most common choice amongst them due to the fact that it can be recycled into pavement that performs as well as, or even better than, pavements made of all-virgin materials [ 55 , 56 ]. Moreover, the same material can be recycled again and again; it never loses its value. The asphalt binder retains its function so that it is reused for its original purpose. The aggregates (rocks, sand, and gravel) in the original pavement are also conserved [57,58]. Sustainability 2020,12, 7160 5 of 19 2.3. Implementation of Circular Economy Principles in Road Construction and Maintenance Policies that encourage the implementation of the principles of CE have already been introduced in some cases. The European Commission, responding to the increasing pressures on natural resources launched the European Resource Efficiency Platform (EREP) in 2012, with a manifesto and policy recommendations that were adopted in Brussels on the 17th of December 2012. The European Resource Efficiency Platform called on business, labor and civil society leaders to support resource efficiency and the move to a circular economy [ 59 ]. The target was to move towards a harmonized and controlled transition from linear economic patterns to circular ones. As described in the published manifesto, the desirable approach would be a transition towards a resource efficient and ultimately restorative CE. After the foundation of the aforementioned platform, which is composed of practitioners and politicians, guidelines have been publicly provided, in order for the implementation of “circular economy(-friendly)” approaches and frameworks to be widely adopted and finally implemented [ 5 , 59 ]. The United Kingdom acting as a pioneer in this context was the first European country to publish standards about the implementation of CE in 2017 [ 28 ]. France followed with the development of voluntary standards called XP X30, published by the French Association for Standardization (ANFOR) in 2018 [ 60 ]. The title is “Circular economy—Circular economy project management system—Requirements and guidelines” and the standards propose a common understanding grid, laying out the terms, principles, and practices relevant to CE. The development of these standards led to the creation of a technical committee within the International Organization for Standardization (ISO TC 323) which is working on enriching and developing international standards in the CE field. The proposed deliverables will apply to any organization or group of organizations wishing to implement CE projects, such as commercial organizations, public services, and not-for-profit organizations. Specifications relevant to already covered and standardized aspects such as eco-design, life cycle assessment, environmental management and sustainable procurement will not be included in the standards. Moreover, in July 2019, Platform CB’23 from The Netherlands published a framework for circular construction, focusing on building works. The requirements for a uniform measurement method of circularity are emphasized and an approach for quantifying circularity is proposed [ 61 ]. Finally, the European Union, understanding the necessity for CE, had officially adopted an action plan in 2015 to help accelerate Europe’s transition towards a CE, boost global competitiveness, promote sustainable economic growth and generate new jobs and in 2019 the Circular Economy Action Plan was completed [62]. The European Commission has invested in CE and sustainability in every sector. For the pavement engineering, and road construction and maintenance sectors, a technical report was published in 2016 [ 63 ], detailing the practices that NRAs and involved stakeholders should be implementing for more sustainable and circular approaches. Moreover, a set of criteria has been developed, that can help stakeholders act immediately even without having a deep knowledge of CE and sustainability. The EU commission has identified some of the most impactful stages and aspects of a road’s lifecycle that when modified accordingly can be significantly beneficial for the environment and the economy, based on the principles of green procurement and CE. The most relevant stages/aspects identified that can be immediately applicable for increased circular performances are: •Resource efficient construction. • Recycled content: high percentages of materials are recycled into asphalt pavements, while complying with the performance requirements for the road pavement. • Excavated materials, soil, and wastes management: excavated materials, soils and wastes that are not hazardous can be reused on site. • Water and habitat conservation: road drainage systems must adequately drain both stormwater from the road surface and sub-surface water from groundwater flows. Moreover, it is suggested that Sustainable Drainage Systems (SUDS) are promoted in an attempt to re-use the drained water. Sustainability 2020,12, 7160 6 of 19 • Maintenance and rehabilitation strategies: a Maintenance & Rehabilitation Plan, that considers all the aforementioned suggestions, should be developed during detailed design. The European Commission has also published a document entitled “Circular Economy: Principles for Buildings Design” [ 64 ] that details the general principles that should be implemented if a more circular approach is to be adopted in the building sector. The document is specifically focused on buildings, but the main principles are presented here because of the similarities that exist between buildings and roads. • Better knowledge is needed about construction techniques to facilitate deconstruction and to enhance durability and adaptability of built assets. • Durability depends on better design, improved performance of construction products and information sharing. •Prevent premature asset demolition by developing a new design culture. •Design products and systems so that they can be easily reused, repaired, recycled, or recovered. While these principles refer to buildings, they can easily and immediately be applied to other built assets such as road pavements, thus assisting the road engineering industry as well. The road engineering industry, by taking under consideration the aforementioned recommendations/suggestions, could potentially improve its environmental performance and sustainability levels while increasing its circularity. 3. Methods Firstly, after presenting a brief background of the CE, the implementation of circular economy principles in the construction and maintenance of roads is presented. Secondly, the national/regional authority roadmaps towards CE that have been published through the European CE Stakeholder Platform are analyzed. Thirdly, a questionnaire about CE and its implementation (NRAs) that was distributed to different NRAs across Europe, is analyzed. In addition, an online research has been conducted via the official websites of the investigated NRAs in order to identify aspects of communication concerning CE. The words “circular economy” and “sustainability” were searched for on the websites and the results were analyzed. When it comes to transport infrastructures and asphalt pavements specifically, it becomes difficult to encompass and conceptualize all these principles in their life cycles. Indeed, there is a plethora of roadmaps towards CE that have been published attempting to pave the way towards achieving circularity at national level but not a lot of effort has been made to specifically address the sector of road engineering. In this study we have identified what has been published by national and/or regional authorities for the road engineering sector that can be implemented towards more circular operational patterns. In Table 1, all the national plans and/or roadmaps published online through the European CE Stakeholder Platform can be found, along with the single roadmap produced by an NRA (Highways England). It is worth mentioning that only the roadmaps published in English were analyzed. Thus, the documents C: Regional plan for the circular economy, Brussels Capital Region, M: Extremadura 2030, N: Strategy of the government of Catalonia: Promoting green and circular economy in Catalonia, O: Circular the Hague: transition to a sustainable economy, were not analyzed. The documents were analyzed according to the criteria of whether or not they present targets, goals, best practices and/or recommendations towards the transition of the road and pavement engineering industry to a more circular way of conducting business. The weight was given to the development of transportation infrastructures and more specifically of asphalt pavements. Moreover, mentions of the building sector that can be immediately applicable to the production of asphalt mixtures, the construction, use, and maintenance of asphalt pavements were taken under consideration. Sustainability 2020,12, 7160 7 of 19 Table 1. National plans and/or roadmaps published online through the European CE Stakeholder Platform (https://circulareconomy.europa.eu/platform/en/strategies?page=1). A. The Danube goes Circular—Transnational Strategy to Accelerate Transition Towards a Circular Economy in the Danube Region (ENGLISH) [65] Austria, Bulgaria, Croatia, Czech Republic, Germany, Hungary, Romania, Slovak Republic, Slovenia, Ukraine, Moldova, Serbia, Montenegro, Bosnia and Herzegovina B. Circular Flanders kick-offstatement (ENGLISH) [66] Belgium C. Regional plan for the circular economy, Brussels Capital Region (DUTCH, FRENCH) [67]Belgium D. Leading the cycle—Finnish road map to a circular economy 2016–2025 (ENGLISH) [68]Finland E. 50 Measures for a 100% Circular Economy (ENGLISH) [69]. France F. German Resource Efficiency Programme II (ENGLISH) [70]. Germany G. National Action Plan on Circular Economy (ENGLISH) [71] Greece H. Towards a Model of Circular Economy for Italy—Overview and Strategic Framework (ENGLISH) [72]Italy A. Luxembourg as a knowledge capital and testing ground for the Circular Economy (ENGLISH) [73]Luxemburg A. Leading the transition: a circular economy action plan for Portugal (ENGLISH) [74]Portugal B. Strategy for the Transition to the Circular Economy in the Municipality of Maribor (ENGLISH) [75]Slovenia C. Roadmap towards the Circular Economy in Slovenia (ENGLISH) [ 76 ] Slovenia D. Extremadura 2030 (SPANISH) [77] Spain E. Strategy of the government of Catalonia: Promoting green and circular economy in Catalonia (SPANISH/CATALAN) [78]Spain F. Circular the Hague: transition to a sustainable economy (DUTCH) [ 79 ] The Netherlands G. A Circular Economy in the Netherlands by 2050 (ENGLISH) [80] The Netherlands H. Kernmethode voor het meten van circulariteit in de bouw (DUTCH/ENGLISH) [61]The Netherlands I. Making Things Last: a circular economy for Scotland (ENGLISH) [ 81 ] United Kingdom J. London’s Circular Economy Route Map (ENGLISH) [82] United Kingdom K. Circular Economy Approach and Routemap * (ENGLISH) [83] United Kingdom * It is worth mentioning that the only National Road Authority (NRA) that has published a publicly available roadmap towards circular economy is Highways England in collaboration with AECOM (Architecture, Engineering, Consulting, Operations, and Maintenance) and Atkins. 3.1. Questionnaire to National Road Authorities Furthermore, in order to focus the research on the field of pavement and road engineering, agencies such as National Road Authorities were under the focal point of the study. The NRAs of different European countries were contacted in order to identify if they are familiar with CE and how they are implementing it. Consequently, a questionnaire was formulated mostly relevant to their sustainability assessment approaches, since they were part of the Pavement LCM project (https://www.pavementlcm.eu/), funded by the Conference of European Directors of Roads (CEDR) and focusing on the life cycle management and sustainability assessment approaches that NRAs could adopt. However, the survey was structured in a manner which was able to provide a qualitative analysis through the questions that can be found in the Appendix A, which are relevant to the CE and were also included to the questionnaire for a more spherical overview. A plethora of European NRAs is Sustainability 2020,12, 7160 8 of 19 in partnership with the funding body, CEDR; thus, most of these NRAs were contacted through email and the ones interested in participating replied. The data and results presented in this paper include all the NRAs that have filled in the questionnaire. It was filled openly by up to 2 persons working within the corresponding NRAs in positions closely related to sustainability and/or sustainability development and assessment. The questionnaire was filled by the NRAs given below. •Austria (ASFiNAG) •Denmark (Danish Road Directorate—Vejdirektoratet) • Germany (Federal Ministry of Transport, Building and Urban Development—Bundesministerium für Verkehr und digitale Infrastruktur) •United Kingdom (Highways England, Transport Scotland, Welsh Government, Roads Service) •Lithuania (Lithuanian Road Administration and family of road engineers) •Norway (Norwegian Public Roads Administration—NPRA) •Slovenia (Slovenian Roads & Infrastructure Agency) •Sweden (Swedish Transport Administration Trafikverket) •Netherlands (Rijkswaterstaat, State advisors for urban development & infrastructure) The questionnaire can be found in Appendix A. 3.2. Web Search: NRAs and CE Communication Having structured the questionnaire to reflect whether or not the NRAs are familiar with the CE and if they are implementing it, the next step was to identify whether or not the NRAs also move towards communicating their circular practices, and in general the ways that they implement or plan to implement the CE; since communication of an organization’s values can often have a significantly positive impact and value. Hence, in order to identify the ways that NRAs communicate CE, an online search was undertaken specified under a textual web search query. The search was conducted online in English and also in the corresponding local language of every investigated NRA, respectively. The official websites of the NRAs that participated in the survey were identified and afterwards, in their “search” function, the words “circular economy” and “sustainability” were searched. The key words were selected in a way that could cover a wide spectrum of CE. Results such as reports and initiatives were reviewed with an end goal to clearly identify how the aforementioned NRAs are trying to communicate to the broader public their commitment to the CE, and what they are doing to integrate circular practices in their operational approaches. The websites of the NRAs that were investigated and the outcomes of the web search, can be found in Section 4.3. 4. Results and Analysis 4.1. Analysis of Roadmaps Produced by National/Regional Authorities towards Circular Economy Analyzing the documents collected from the European Circular Economy Stakeholder Platform, it becomes obvious that the principles of CE within the transportation sector are not well established yet. It is worth mentioning that only one of the analyzed documents has been published by an NRA, i.e., Highways England, while the rest have been published by governmental bodies, ministries, companies and/or groups and platforms formed to promote circular thinking. Not all of them deliver a specific set of strategic actions and indicators, metrics, or desirable targets to be reached. In detail, the most common elements of the aforementioned road maps, which include aspects of the pavement engineering industry can be seen in Table 2. Sustainability 2020,12, 7160 9 of 19 Table 2. Summary of the approaches, strategies, and indicators directly applicable to asphalt pavements originating from the analyzed documents. Highways England (UK) •A detailed plan is deployed until 2025, including the aspects of governance, procurement, monitoring and reporting and the development of tools and guidelines. •Potential indicators: material use/km of road built, material use in schemes, financial performance, savings, and the content of materials purchased, used and recycled. • Significant weight given to communication, monitoring and reporting. Platform CB23 (The Netherlands) • One of the most analytical and comprehensive approaches towards the implementation of CE within the construction sector. •Focuses on the built environment. •Describes “passports for construction”, a digital representation of construction works and the value that than can be created with these data. •Life Cycle Assessment is coupled with the creation of a passport and the metrics of alternative passports are compared. •Approach to quantify the material circularity index of construction materials and processes. •Quantity of materials used, available for next cycle, lost. •Influence on the quality of the environment. • Quantity of existing value used, value available for next cycle, existing value lost. German Resource Efficiency Programme II • Utilization of secondary materials for asphalt and concrete pavements. • Calculation of the reclaimed asphalt percentage that is used in paving activities, and the percentage of recycled aggregate used as concrete aggregate relative to total volume of recycled construction materials. •Minimization of the cumulative raw material consumption and cumulative energy expenditure in roadbuilding by maximizing the recycling rates of asphalt. •Raw material productivity (Economic indicator): Promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all via resource conservation and using resources economically and efficiently (total raw material productivity =(GDP+imports)/raw material input). 50 Measures for a 100% Circular Economy (France) •Key objectives and measures for better production, consumption, waste management, mobilization of all sectors. •Increased use of secondary materials. •Uptake of product-service systems. •Adaptation of waste regulations to support CE. •Allocation of dedicated funding towards the support of CE implementation. Luxembourg as a knowledge capital and testing ground for the Circular Economy •Establishment of a materials within infrastructures inventory. • Innovate designs and usage models with higher material productivity. •Improve residual value of materials and components. •Improve recycling and component harvesting rate. •Material passports and/or material banking. •Modular designs. •Leasing of assets and equipment. The most commonly presented indicators are the percentage of materials reused and/or recycled, resource efficiency, material circularity index and raw material productivity. Some of the most detailed publications provide action plans for each sector to follow and targets that need to be fulfilled under specific timetables, in order for the transition to a CE to be realized. The majority of the documents Sustainability 2020,12, 7160 16 of 19 2. Richard, C.; Amit, P. Exploiting Natural Resources: Growth, Instability, and Conflict in the Middle East and Asia; The Henry L. 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