Introduction to Environmental Disasters
Most large-scale environmental disasters, whether present during an historic time (like the Black Death, or the explosion and fire in 1916 on the munitions ship Mont Blanc, which destroyed Halifax, Nova Scotia) or contemporary in time (e.g., the 1984 Bhopal, 1998 Catarina, 2003 European heat wave, 2005 Hurricane Katrina, 2010 Deepwater Horizon and the 2011 Fukushima), are associated with complex combinations of human and natural factors. It is of interest, indeed, to explore the roots of such disasters.
The 25 largest known environmental and atmospheric disasters related to human causes, ranked by the number of deaths, locations, and causes, are surveyed in this paper. An environmental disaster is almost necessarily anthropogenic, often involving mismanagement or lack of appreciation of potentially dangerous conditions, as well as underlying short-term attempts to increase profit or cut costs. Therefore, to protect lives and long-term environmental health and stability, it is useful to study the planned and unplanned changes that lead to such events. What are the differences between how governments, companies, and research institutions responded to these disasters – such as the tribunals to ensure justice, prevention, reconstruction, rebuilding, monitoring, regulation, and implementation of long-term environmental health? What are the similarities between efforts such as the design of international instruments relating to pollution monitoring and reporting, accounting methods and the implementation of policies and management measures, including the development of linkages between economic, environmental and social information?
Case Studies of the Largest Environmental Disasters
The word “technology” has an array of meanings almost as complex as its prismatic nature. Technology is itself but a derivation or partial manifestation of nature. The properties of technology are twofold, and follow regimes of natural laws. Then why, in man’s conscious state, have results of emerging man-made scientific knowledge turned into an occurrence of copious disasters? How to prevent and minimize damages of the environmental disasters that seem quite inevitable due to the exponential growth of scientific and technical progress? Recovery of the environment needs insight into many aspects: re-evaluation of technology and development, feasible industrial control, and all-embracing legal concepts. The confinement of secret chambers of environmental knowledge should be unlocked, effective powerful countermeasures given an open-air staging for minimizing the adverse ecological consequences of environmental disasters caused by complex technological catastrophes.
The Black Sea – The Black Sea is one of the largest semi-enclosed basins with an area of 5 x 106 km2. The deepwater floor sediments are heavy metal rich, due to both anthropogenic and natural sources. Most of these metals are locked inside the sediment strata and have not been removed by the water-sediment exchange processes associated with redox conditions. Based on the findings of this investigation, large-scale ore extraction needs to be proceeded safely. If not, it could conceivably destroy important biological and microbial systems, increase nutrient fluxes into the water column from the deeper sediments, and redox conditions in the overlying waters leading to the formation of hydrogen sulfide in the hypoxic and anoxic bottom waters. The future path of the Black Sea should be carefully considered. The results may have relevance to the future management of large and/or isolated bodies of seawater throughout the world.
Causes and Contributing Factors
The causes of the largest environmental disasters in history are the subject of numerous studies, debates in the scientific community, and at the international level in various organizations. The causes of man-made environmental disasters differ by type. The causes of nuclear disasters are a number of poorly designed or operated reactors, the use of nuclear power plants for military purposes, regulatory and operational shortcomings, a flawed communication strategy, the cover-up of problems, and the use of incompetent personnel. The causes of technological and industrial disasters are any adverse activity of a person during management, planning, or production that led to weak structures, civil works, and fire protection systems; using poor-quality raw materials and cheap equipment and technology; using equipment for an extended period of time that had served its intended purpose; and ignoring the influence of environmentally extreme factors.
The causes of aviation disasters are numerous faults in aircraft and engine design associated with implementing new materials and advanced technologies aimed at meeting ambitious cost, safety, and environmental targets, as well as design offices that did not manage their product integrity in the presence of market pressures and control from clients. A number of catastrophes from the discovery of oil fields or the transportation of oil with tankers (accidents) led to environmental disasters; the most famous cases are the oil spills of Exxon Valdez and the Deepwater Horizon. The causes of oil spills are a fascination with innovation and the desire to reduce operating costs, increases in transportation capacity, improvement of economic performance, minimizing regulatory constraints, considering the financial aspect in corporate strategy at the expense of safety, and the lack of consideration of ecological factors as a contributor to industrial risks. Factors contributing to different types of man-made environmental disasters and affecting their magnitude were revealed after the study of the causes of accidents and the lessons learned from negative environmental impacts. Former USSR republics and socialist countries provided the largest amount of material for these studies, but examples of economic development of emerging market economies were also noted.
Environmental Impacts
The United Nations and the World Commission on Environment and Development have agreed that the contamination of the environment with heavy metals, oil, hazardous substances, radiation, and microorganisms presents the most visible and serious symptoms of global environmental degradation. The destruction of terrestrial and aquatic ecosystems in the vicinity of the contamination source, which emerged from the environmental disaster, lipid disorders and reduced body mass in ecologically significant species. It should be noted that various biochemical processes occur regularly, including development, growth, reproduction, and mortality of significant biological species. The changing structure and functions of habitats have already been noted in the Chernobyl Exclusion Zone, which is particularly significant for the natural migration of birds. The fact that disturbed lands are more fertile than undisturbed lands, which are a prime condition for the reclamation of the territories.
Lessons Learned and Strategies for Prevention
The understanding of how environmental disasters develop has evolved significantly over time, stemming from specific case studies. In the case of chemical accidents, for example, the Caulum Silo Disaster was a wealth of information for the development of laws, regulations, standards, guidelines, and recommendations for the prevention or reduction of chemical accidents worldwide. Similarly, in the cases of catastrophic accidents, the Bhopal Disaster, the Chernobyl Disaster, and the Fukushima Accident have served as key examples, providing broad knowledge about how to significantly reduce the risk of their recurrence. This knowledge, in some cases, emerged very soon after the accidents since with time, the occurrence of new accidents evolve memories and new generations of professionals and managers are responsible for maintaining a high level of safety. In the case of industrial-related accidents, the impulse of initiatives that were grounded on promoting international cooperation and trust was great. However, given the growing frequency, size and environmental and social impacts of catastrophic events related to changed climatic conditions, the promotion of policies and agreements aimed at reducing greenhouse gas emissions to stop or revert global warming have generated intense debates.
This chapter presents the main lessons learned from various disasters and accidents and the strategies that have been developed to prevent the recurrence of these events. This section is relevant for both undergraduate and graduate “Introduction to Environmental Engineering” courses. Focusing on the case of the Rovuma Valley in Mozambique, several practical applications have been developed, and the results presented and discussed during classes. This experience is extremely interesting as it has contributed to attract the attention of students and to involve them in discussions about prevention strategies in environmental engineering.
