Abstract Geological disposal provides the safe long-term management solution for higher-activity radioactive waste. The development of a repository (or geological disposal facility) requires a systematic and integrated approach, taking into account the characteristics of the waste to be emplaced, the enclosing engineered barriers, and the host rock and its geological setting. Clays and clayey material are important in the development of many national geological disposal systems. Clays exhibit many interesting properties, and are proposed both as host rocks and as material for engineered barriers. Whatever their use, clays present various characteristics that make them high-quality barriers to the migration of radionuclides and chemical contaminants. As host rocks, clays are, in addition, hydrogeologically, geochemically and mechanically stable over geological timescales (i.e. millions of years).

The particle-size distribution of oil-sands tailings has always figured prominently in the mine planning and overall operations and closure strategy in surface-mined oil sands. In oil-sands applications, the convention is to define the sand as the mineral components >44 μm in size and the fines as the mineral component which is <44 μm. The water-based extraction process uses 2 m 3 of water to extract the bitumen from 1 m 3 of oil sand, and as the bulk of this water is recycled, large containment areas are required to maintain a supply of extraction water. A significant proportion of water that is not recycled is retained in both the sand and fines components of the resulting tailings streams and the essence of tailings management comes down to separating and managing the water that can be recovered from the tailings. As the mining operations have become larger, and ore properties vary over wider ranges, the designation of sand and fines was simply inadequate in explaining the behavior of many of the tailings and a thorough understanding of the entire particle-size distribution became more important. Due in part to the upgrading and refinery operations often associated with bitumen production, the oil sands industry is relatively sophisticated in its approach to tailings characterization and tailings management. As a result, any discussion of clays can, and often does, include both a size and mineralogy component. In any case, there is no doubt about the importance of understanding and quantifying the clay component of any tailings stream when defining a dewatering or management strategy. Historically, it might have been argued that the strong correlation between clay content and fines content would be an adequate characterization and tailings-planning parameter. Although this is still largely true, the clay to fines correlations can sometimes be measurably different from operation to operation, resulting in varying tailings performance. In addition, some tailings-management options such as thickeners and centrifuges can separate the fines fraction and even the clay fraction in a fluid fine tailings stream. These upset operational modes can create what are known colloquially as Franken-Fines, a stream with a very disproportionately high clay content that can create an equally disproportionate tailings problem. The tailings strategies that will be discussed include composite/consolidated/non-segregating tailings, thickening, freeze-thaw processes, rim ditching, thin lift dewatering, and centrifugation. The present chapter outlines the evolution of many of these tailings-management strategies that have been tested extensively or are currently in use in the surface-mined oil-sands industry, with a particular emphasis on the importance of understanding the clay size and clay mineralogy in the evaluation and understanding of tailings dewatering performance.

The long-term success of water projects in water-stressed communities hinges not only on providing access to safe water, but also on equipping communities for sustainable resource management. Coupling research with education facilitates sustainability by growing local hydrogeologic knowledge and supporting prudent management. Adjusting management practices requires time, and it is helped through collaboration and trust between researchers and stakeholders. Research and education were integrated during an evaluation of groundwater resource sustainability and wastewater management practices at Restoration Gateway, an orphanage in northern Uganda. Basic hydrogeologic understanding was established through field work, staff interviews, and literature. An opportunity to collaborate with a visiting surveying and master planning team leveraged time spent on-site for greater results. Hydrologic education occurred formally and informally, through science lessons at the orphanage school and daily interactions with the Restoration Gateway population. Staff were interviewed regarding as-built designs, water usage, and wastewater management practices. Knowledge gained enabled researchers to make recommendations for preserving groundwater quantity and quality. Site-specific information was incorporated into a master plan for future development. Education efforts and trust gained through immersion in the life of Restoration Gateway increased awareness and acceptance regarding groundwater sustainability. In international work, it can be easy to focus on maximizing time for research and associated tasks. This case study presents ideas for spending time in local participation and education. Participation in the local community, involving them in research efforts, and building their hydrogeologic understanding improve the chances of recommendations being adopted and can foster long-term partnerships that enhance groundwater sustainability.

The new high-speed, high-capacity Treviglio-Brescia railway line is an integral part of the Trans-European Transport Network, the “Mediterranean Corridor,” and constitutes a critical stage in the construction of the high-speed, high-capacity Milan-Verona railway line, which extends a total of 140 km, 27 km of which have been in operation between Milan and Treviglio since 2007. The activities currently under way include the construction of a railway line covering a distance of ~52 km between Treviglio and Brescia, and the completion of a series of complementary projects to mitigate the interference with other infrastructures (e.g., canals, underground utilities) and new road systems. Geological investigations have been necessary during the course of the work, to manage excavations and excavated materials, to manage abandoned waste encountered along the line, and for remediation of contaminated sites. In addition to the characterization of the project area, data collected have contributed to the Environmental Monitoring Plan issued by the Consorzio Eni per l’Alta Velocità (CEPAV Due), which will monitor for potential environmental impacts caused by the execution of the project, particularly related to the soil, surface water, and groundwater, and the project measures needed to reduce environmental impact. This paper provides an overview of the activities carried out so far, as illustrated with some case studies.

We reviewed the current state of waste management practices in Nigeria using examples from different parts of the country. Commonly practiced waste disposal methods in Nigeria, such as burial, open-air burning, and open dumping, were found to be ineffective and detrimental to public health and the environment. It was also shown that waste management cannot be successfully operated as a social service. Rather, the generator of waste must be held responsible. Problems confronting efficient waste management in Nigeria include the proliferation of unplanned settlements, traffic congestion, insecurity, and ignorance. An experimental model being used in Lagos State for the management of wastes may be the solution. Given the rate of population growth, industrialization, and urbanization, forward-looking and effective waste management plans need to be set in motion for the protection of public health. Such plans must involve all stakeholders, including the waste generators, the private sector, the informal sector, and regulatory agencies.

Earth systems, when understood and respected, have the intrinsic capability to be instrumental for sustainable international development. If applied wisely without sophisticated technology, natural processes themselves can serve to sustain and prosper life in specific situations. Global initiatives to provide safe surface and groundwater are booming, but a parallel emphasis on sustainable sanitation is lagging, leaving 2.5 billion people without access to improved sanitation. Many technically sophisticated sanitation systems exist but are beyond the means of those same billions. The Water and Sewage Transformation Endeavor (W.A.S.T.E.) is a program at Wheaton College (Wheaton, Illinois) bringing together undergraduate students and faculty from various natural and social sciences to address the global need for improved sanitation. The goal of the program is to develop a low-tech wastewater treatment system for the Global South and beyond. A laboratory-scale waste stabilization pond system was constructed and studied to compare its effectiveness at reducing biological oxygen demand (BOD), as an indicator of pathogen disinfection, by varying light intensity, temperature, and detention time. The system with the highest light intensity and temperature and longest detention time performed the best, achieving 95% total BOD reduction. The project time line includes phase 1 indoor experimentation, phase 2 installation and operation of an outdoor pilot system, and the final phase 3 development of training programs for deployment of the technology into areas of need. The overall program has already proven to be an excellent educational opportunity for undergraduate students. It will ideally benefit many other student practitioners, and local trainees at candidate sites.

The University of Missouri–Kansas City (UMKC) has been offering educational programs in waste management and environmental science for ~25 yr and has recently added a sustainability minor to its bachelor’s degree in environmental science and environmental studies. With collective input from students, faculty, administrators, and staff, the university has established a highly successful sustainability program geared toward attaining zero waste. Students enrolled in the Introduction to Waste Management class are required to work on a term project that involves performing a waste audit. For the past several years, students have been conducting waste audits at various buildings on the campus. The term project not only allows students to gain familiarity with the principles of waste audits, but it also provides valuable hands-on experience with the procedures used for conducting a waste audit, data collection, analyses, interpretation, and preparing a written report followed by an oral Power-Point presentation. These reports have played a key role in designing a successful recycling program at UMKC that led to its earning first place among 523 colleges and universities in the annual RecycleMania competition in 2013, as well as its inclusion in Sierra magazine’s listing of top 100 “green schools” in the country. This paper includes a profile of the university and a detailed discussion of the waste audit project, recycling program, and sustainability efforts, along with suggestions on how to implement successful recycling programs elsewhere.