The coronavirus disease 2019 pandemic has posed severe threats to humans and the geoenvironment. The findings of severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) traces in waste water and the practice of disinfecting outdoor spaces in several cities in the world, which can result into the entry of disinfectants and their by-products into storm drainage systems and their subsequent discharge into rivers and coastal waters, raise the issue of environmental, ecological and public health effects. The aims of the current paper are to investigate the potential of water and waste water to operate as transmission routes for Sars-CoV-2 and the risks of this to public health and the geoenvironment. Additionally, several developing countries are characterised by low water-related disaster resilience and low household water security, with measures for protection of water resources and technologies for clean water and sanitation being substandard or not in place. To mitigate the impact of the pandemic in such cases, practical recommendations are provided herein. The paper calls for the enhancement of research into the migration mechanisms of viruses in various media, as well as in the formation of trihalomethanes and other disinfectant by-products in the geoenvironment, in order to develop robust solutions to combat the effects of the current and future pandemics.

Most of the challenging soil deposits necessitate their stabilization either by adopting mechanical modification, which includes soil replacement, compaction, surcharge loading and piling or chemical alteration by using lime, cement, and chemical additives. These methods of stabilization are oriented towards improving certain defined properties such as plasticity, swell potential, strength, and density of the soil mass. Besides, one of the most crucial challenges that is faced is “stabilization induced cracking of the fine-grained soils,” which turns out to be the basic reason for the failure of the soil mass and subsequent failure of the structures. However, concerns such as non-availability of the ideal soil for replacement of the native soil and even inaccessibility of the site and laborious soil-stabilizer mixing methods necessitate exploring suitable alternatives for stabilization of such soil deposits that adds up to the vows of the practicing engineers. A few other pressing issues which need to be addressed are the adverse effects caused by these additives on the environment (viz., release of greenhouse gases and/or subsequent leaching of chemicals into the ground water). In such a scenario, application of industrial by products (viz., fly ash, cement kiln dust, blast furnace slag, rice husk ash, silica fumes, red mud, and textile waste), which could be defined as “sustainable materials,” find a special place in the modern-day soil stabilization and modification exercise. Keeping this in view, a critical synthesis of the literature has been presented in this paper, which showcases superiority of the sustainable materials over the conventionally used soil stabilizers and the need for conducting further research to make these materials an easy and choicest replacement over the former.

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Desiccation cracking is a phenomenon commonly associated with the fine-grained soils, which initiates at their surface and subsequently propagates deeper inside their matrix. Hence, for safe and durable infrastructure development, stabilization of such soils becomes important. In order to stabilize these soils, cement, chemicals, and fibers have been employed by earlier researchers. However, in recent times, the ill effects of these stabilizers on the ecosystem have been realized, and hence their replacement with sustainable materials that are mostly industrial by-products is becoming necessary. This philosophy would not only conserve natural resources, but would also result in a “marriage” between “two suitable” materials to create a “synergy” within the ecosystem. With this in view, the ground granulated blast furnace slag (GGBS), a by-product from the iron and steel plants, was activated by red mud (RM), a by-product from alumina manufacturing units, with an objective to establish its utility in stabilizing the fine-grained soils against desiccation cracking. To achieve this, the parameter crack intensity factor (CIF), which has been employed by earlier researchers to quantify cracking characteristics of the (virgin) soil mass, has been employed for the soils amended with GGBS and RM. Subsequently, the CIF has been correlated with the soil specific parameters (viz., cation exchange capacity and tensile strength) and the environmental conditions (viz., humidity and temperature), represented by the evaporation rate of the soil mass. Based on these extensive investigations, it has been demonstrated that such correlations would be very useful for selection of the right combination of the soil and sustainable material(s) to achieve a stabilized system of the fine-grained soil. It has been put forth through this study that the by-products chosen exhibit high potential to stabilize the fine-grained soils, which also resulted in alteration of their micro-structure and strength post stabilization. Furthermore, studies have been carried out to establish the effect of addition of industrial by-products to virgin soils, mainly in terms of their micro-structure, which in turn controls their strength.