Coal tar was used in Sweden for the production of asphalt and for the drenching of stabilization gravel until 1973. The tar has high concentrations of polycyclic aromatic hydrocarbons (PAH), some of which may be strongly carcinogenic. Approximately 20 million tonnes of tar‐containing asphalt is present in the public roads in Sweden. Used asphalt from rebuilding can be classified as hazardous waste according to the Swedish Waste Act. The cost of treating the material removed as hazardous waste can be very high due to the large amount that has to be treated, and the total environmental benefit is unclear. The transport of used asphalt to landfill or combustion will affect other environmental targets. The present project, based on three case studies of road projects in Sweden, evaluates the consequences of four scenarios for handling the material: reuse, landfill, biological treatment, and incineration. The results show that reuse of the coal tar‐containing materials in new road construction is the most favorable alternative in terms of cost, material use, land use, energy consumption, and air emissions.
Universities all over the world have developed Massive Online Open Courses (MOOCs) to attract students and explore new ways of learning. The MOOC "Sustainability in Everyday Life" (SiEL) is currently in its design and early development stage at Chalmers University of Technology. It aims at developing the MOOC participant's capacity to appreciate the complexity of sustainable everyday life by developing skills such as systems thinking and critical reflection on the information flow in public media. This paper aims at sharing first experiences regarding the design and early development of the SiEL MOOC and identifying the role(s) of the teachers and its features during the course design and early development based on these first experiences. An action research approach was used to reach these aims, and the teachers' narratives about these first experiences were used as data source. Three distinct processes (pedagogical, production and interaction) and six roles (owners, teachers, learners, designers, developers and negotiators) were identified. The teachers' roles and the processes and activities taking place during the design and early development are closely linked to each other and need to be carefully considered in order to guarantee a successful MOOC design and development process.
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