Environmental Risk Assessment by Mhammed Nour

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  • 1. 1- Introduction to ERA. 2- Overview. 3- Definition of ERA. 4- the Basic framework of ERA. 5- ERA in the Context of EIA. 6- Problems with terminology. 7- Legislative and policy background. 8- Key Steps in Performing an ERA. 9- Different Levels Of ERA. 10- Challenges facing the ERA. 11- Risk Communication. 12- Conclusion.
  • 2. Risk Provide an answer to three keys questions: - What can go wrong ? - How likely is it ? - What are the consequences ?
  • 3. -what can be done to manage any risks identified & who should be involved?
  • 4. Mainly on: Environmental Issues Ecological Issues Human Issues Not mentioned “Economical Concerns” as well !
  • 5. There is now a wealth of publications  coming from a guiding principles set by governments for Public Domain Risk Analyses, To handbooks Describe more detailed approaches to a particular aspect of risk assessment. In the last ten years, there have been  several seminal textbooks summarizing a wealth of scientific papers on all aspects of ecological and human risk assessment.
  • 6. EIA practitioners are also increasingly  familiarsing themselves with risk assessment as a complementary and powerful tool for analysis. However, ERA are typically undertaken by a  separate specialists (trained for example in software applications).
  • 7. Despite the government guidance , there  are still some issues related to where the term “Impact” is used , rightly or wrongly In an interchangeable way with “Risk”.
  • 8. this chapter was written with the needs of the EIA practitioners in mind, rather than a Risk Specialist. And it seeks to demonstrate the considerable benefits of following a Risk-Based approach.
  • 9. From an EIA perspective, Risk Assessment  has conventionally been used as a tool for “prediction” & “Evaluation”. But this chapter Also seeks to explore it’s role as a complementary approach in it’s own rights.
  • 10. Risk Assessment is well established in fields  of banking, Insurance, & Engineering as a management tool for dealing with “Uncertainty”. It is also used as a tool for improving  occupational safety & setting priorities for the allocation of resources.
  • 11.  Back several decades, Individuals used risk assessment Consciously or Sub-Consciously, in their everyday lives.  Such as Negotiating a busy road as a pedestrian, or place a bet on a horse race.  However, these days Risk Assessment Techniques have been extended to wider Environmental Considerations.
  • 12. Environmental Risk Assessment (ERA): a generic term for a series of tools and techniques concerned with the structured gathering of available information about Environmental Risks, and then the formation of a judgment about them. Risk Management: Involves reaching decisions on a range of options that balance these risks against the costs and benefits ( Specifically Including the Environmental Costs and Benefits).
  • 13. Communicating the nature and scale of risk and  the options is also a key part of the process. The next sketch shows the basic elements of a framework within which ERA may be carried out. Including the options of generic and tailored Quantitative Risk Assessment. QRA : use of measurable , objective data to determine asset of values , probability of loss , and Associated Risk(s). http://www.businessdictionary.com
  • 14. Risk Screening Risk Prioritisation High Priority Risk Generic QRA Low Priority Risks Complex Risks Tailored QRA Iteration Options Appraisal Social Issues Technical Assessment Economics Environmental Management Risk Management
  • 15. ERA and EIA are often overlap and are mutually supportive for  each other, as they both deal with Uncertainty. Uncertainty: Is an inherent and unavoidable aspect of EIA  and is a characteristic of all natural systems. Uncertainty arise from a variety of sources , Including the  available Data and The Decision making Process it self. Approaches for managing uncertainty have been developed in  parallel with risk assessment techniques.
  • 16.  ERA and EIA are very similar concepts that broadly have the same goals and tools that can inform decision-makers about frequency and magnitude of adverse environmental impacts that arise from certain activities.  A major additional aspect provided by ERA is that it can provide probabilities to predicted impacts.  As a response to that, a manager would like to mitigate or eliminate that particular impact or to reduce it’s potential risk.  Alternative sites or technology options may be desirable when doing risk management as seen in the next example.
  • 17.  Type ( Flood Risk Assessment )  Description ( the procedure set out by the Government aims to avoid inappropriate development in areas at risk from flooding ).  A Flood Risk Assessment ( needs to assess the risk from all forms of flooding , to and from , the development and demonstrate how these flood risks will be managed , taking climatic changes into account ).
  • 18.  ERA Ensuring acceptability of site-specific risks and Hazards.  ERAs are Legal requirement for activates that potentially cause damage to the environment or human Health.  However, the question arises as to when in the planning process ERAs should be carried out? - LPAs have stipulated that ERA should submitted at the same time as an EIA.
  • 19.  As for that, potentially there are considerable Cost-Saving and time advantages by combining approaches such as ERA and EIA.
  • 20. One of the difficulties with the concept of risk is that it has been developed and applied across a broad range of disciplines and activities, leading to different Terminologies.
  • 21. Such as The following definitions that employed in this chapter: Hazard: a property or situation with the potential to cause Harm. Risk: a combination of the probability, or frequency of the occurrence of a particular hazard and the Magnitude of the adverse effects or harm arising to the quality of human health or the environment. Probability: the occurrence of a particular event in a given period of time or among a number of possible events. Risk Management: the process of implementing decisions about accepting or altering risks.
  • 22. When EIA has been evolving for more than two decades in UK, it’s only in the last decades that policies for consistent approaches to risk assessment have been developed for environmental protection. Then many regulations and proposed legislation required for Human Health Risk Assessment. Risk assessment concerned with ecosystem is still not specifically defined in legislation unlike EIA.
  • 23. In the other hand, risk terminology has crept into the ecological chapters of many Environmental Statements in the UK, promoted by the acceptance of Uncertainty about Impacts and effectiveness of it’s Mitigations. And as for Interest groups and source of information , ERA and Management had been undertaken as a commitment to Sustainable Development. For Example : The Environmental Agency, through it’s National Center for Risk Analysis and Options Appraisal.
  • 24. 1- Hazard identification and Analysis. For a hazard to result in harm there must be a way in which it can be affect a “Receptor”. Or as some specialists use the term “Source (Hazard)– pathway–receptor”. For example in Flood Defense Scheme might be: -How likely is it that the scheme will over-topped with flood water? (Hazard) -How might people living on the neighboring floodplain be exposed? (Pathway) -What effects might be experienced by an exposed individual? (Receptor)
  • 25. Event tree analysis: is an accepted means of undertaking hazard analysis. It’s Important not to make them to complicated for the easy of understanding. Example: event tree analysis for accidental spillages and pollution risk (next slide). Hazard analysis also involve Estimating the probability or chance of occurrence of a particular Hazard.
  • 26. Do nothing (severe pollution) significant Monitor Intervene (contain and mitigate) Do Nothing insignificant Do nothing (severe pollution) significant SPILLAGE Monitor Intervene (contain and mitigate) Monitor insignificant Do nothing (severe pollution) Intervene significant Point of uncertainty Final Value Monitor Intervene (contain and mitigate) insignificant
  • 27. 2- Exposure Assessment. Examine the potential consequences associated with exposure to a hazardous event. Ex-(Chemical Spell). By taking account for these considerations: I - A clear definition of the hazard. II - the characteristic of the local environment. III - the behavior of the Hazard. IV - the specific “Dose-Response” relationships that might be known for particular species or environmental feature.
  • 28. Determining the 1st factor is relatively straightforward process , but to determine the other 3 is difficult & complex. (Example of a various levels of consequences) Very High Risk: Ecosystem Irreversibly altered, no recovery, over 100Km2affected. High Risk: Ecosystem altered, but not irreversibly, recover may take long as 50 years, 50-100 Km2 affected. Moderate Risk: only one component of the ecosystem affected, 10 years of recovery period. Low Risk: Temporary alternation, less than 0.5Km2, less than 5 years of recovery period. Very Low Risk: Temporary alternation, very localized, and minor consequences.
  • 29. 3- Risk Estimation. Risk can be determined by combining the result of hazard and consequences analysis. The simplest form of Risk Estimation is “matrix”. Such matrices designed to be simple or complex as appropriate. Approaches to complete these matrices can be qualitative, quantative, or a combination for both. Such approaches that considered more complex or more controversial, the use of “Multi-Criteria Analysis”.
  • 30.  In Risk Estimations , sometimes it is possible to present risk results in Numerical Terms.  Example : that there is a 20% chance that the use of pesticide will lead to the loss of 50% of butterfly in a certain ecosystem.
  • 31.  The important in this step is in the “Judgment of the acceptability of the risk” , By considering it’s effect on Human health and the Environmental Components.  Option appraisal can be useful in authoring “Alternative” Ex : For Each option, what are risks, costs and Benefits?
  • 32. In risk management it is possibly to pinpoint where the improvements could be made. Risk Management uses the ERA’s Results to Mitigate or eliminate unacceptable Risks. But it’s important that to consider where or not a particular risk management measures not to lead to a secondary consequences. Also in risk management, it’s important not to direct a huge fund at a minor Risk.
  • 33. The different levels of risk assessment can be describe as following : 1- Risk Screening : determine the range of risks , and the factors that control whether they will result in environmental changes. 2- Risk Prioritization : Describe the most Important Risks. 3- Generic Quantative Risk Assessment : the use of generally available and tested models to provide a simple quantification of the risks. 4- Tailored Quantative Risk Assessment : the development of a specific models to meet a particular purposes (Usually Complex And Costly).
  • 34. Since ERA deals with Uncertainty measurements , the main challenges that facing ERA are related to some factors that leading to Uncertainty in ERA as described in the next slide.
  • 35. 1- Ecosystems are open, dynamic and complex system with “Built-in” variability and Recoverability. 2- Individuals sub-systems may be interdependent. 3- recovery from a particular impacts may be over a time span longer than human life. 4- it’s sometimes difficult to measure causal relationships. 5- persisted materials may cause Irreversible changes. 6- Synergistic Impacts may arise. 7- perceived risk(s) may be just as important as the real risk (if not more).
  • 36. However, if the best available information at the  time is used, and erroneous data discounted, the gross errors can be Avoided.
  • 37. Risk communication mean : that all decision-making should bring together all relevant social, political, economic, and ethical factors in selecting an appropriate risk management option. Communicating allow people to participate in decisionmaking and management processes, if they where effectively presented. It is important that communication between risk experts and decision-makers is appropriate.
  • 38. A more open approaches in risk communication is to create a dialogue about what the public already knows about risk and to take on board the public’s insight and views on particular risk management option. In communicating risk it is important for risk experts to convey that there is no such thing as “risk-free” world. And there are considerable uncertainties in scientific knowledge.
  • 39. EIA and ERA are Similar forms of impact assessment. While EIA currently remains the predominantly used tool for assessing the potential impacts of projects and proposals. also it is clear that ERA has much to offer both in supportive capacity and as a complementary technique.
  • 40. Risk Assessment Can Avoid Giving Wrong Answers But It Cannot Give Uniquely Right Answers