Wednesday, August 21, 2019
Risk assessment and environmental impact assessment
Risk assessment and environmental impact assessment SECTION 1 1.1 INTRODUCTION This report is on the use of risk assessment (RA) in Environmental impact assessment (EIA). Over the last three decades, there has been a remarkable growth of environmental issues in sustainability and the better management of development in harmony with the environment (Glasson at al 2004). The most popular and widely used environmental management techniques are EIA and RA. EIA is a process to identify and predict the impact on the environment and on mans health and well being of legislative proposals, policies programmes, projects and operational procedures, and to interpret and communicate information about the impacts (Munn 1979). The EIA process includes screening, scoping, impact prediction and evaluation, impact mitigation, decision making (EIA follow up) with public participation and consideration of alternatives potentially incorporated in all the stages of the process (Woods 1995, Canter 1996, Lee and George 2000). The US National Research council (NRC) defines RA as the characterization of the potential adverse effect of human exposure on environmental hazards. A special assessment procedure that aims at tackling certain consequences of human activities is called Risk Assessment (Demidova and Cherp). The stages in risk assessment are as follows: hazard identification, exposure assessment, risk estimation, risk evaluation and risk management (Eduljee 1999). Environmental risk assessment is a generic term for the series of tools and environmental risks and the formation of judgement about them. (DOE 1995, DETR2000) Risk assessment emerged in the mid to late 1970s as an administrative requirement in the form of both statues and executive orders requiring not only more extensive documentation to justify proposed risk regulation, but also the balancing of risk against economic costs and benefits. (Atkisson et al 1985). Environmental Health risk assessment has been defined as the systematic scientific characterization of potential adverse health effect resulting from human exposure to hazardous agents or situations (Faustman and Omenn 2001). In concept, EIA and RA have evolved as parallel and sometimes overlapping procedures for rational reform to policy making (Andrews 1995). The purpose of both concepts is to provide an acceptable basis for making public decisions, not necessarily to generate new scientific knowledge (Andrews 1995). Table 1 below summarizes the similarities and differences of EIA and RA. 1.2 SIMILARITIES AND DIFFERENCES IN RA AND EIA The most important similarity is comparing the stages of RA with those of the EIA process. Thus, hazard identification in RA is equivalent to screening and scoping in EIA, risk estimation is equivalent to impact prediction in EIA, risk evaluation is equivalent to impact prediction in EIA (determining the significance of the impact) while mitigation in EIA can be equated to risk management (specifically risk reduction and control). (Eduljee 1999). SECTION 2 2.1 BRIEF DESCRIPTION OF THE TWO CASE STUDIES Two EIA case studies will be compared from two different industrial sectors and they are the Berkeley nuclear power station where a new building for radioactive waste is to be constructed and the A350 Westbury bypass. The aim of this report is to examine how environmental/health risk has been used in each of these EIAs and the advantage or potential for improving the use of environmental /health risk assessment in these EIAs. 2.11 A350 WESTBURY BYPASS- CASE A The construction scheme will comprise approximately 5.8 kilometres of new single carriage way around the eastern and northern sides of Westbury and it aims to provide traffic relief for Westbury, allowing road space in the town to be reallocated to other modes, improve journey time reliability of the A350 route and improve access to employment areas, particularly the West Wilts Trading Estate, and between the west Wiltshire towns. The construction phase will last between 18 months to 2 years and would involve site preparation, earthworks main road construction and construction of final surfaces. Impacts identified resulting from construction is as follows Generation of noise and dust with earthworks and vehicular movement Pollution risk associated with working in close proximity to surface and groundwater resources. Possible disturbance of ecological and heritage resources Generation and disposal of waste Change of land use pattern Post construction impacts were identified as road traffic and emissions from traffic. (Wiltshire county council, 2007) 2.12 BERKELEY NUCLEAR POWER STATION-CASE B Magnox electrical Limited has proposed to construct an intermediate level radioactive waste (ILW) storage building on Berkeley nuclear licensed site. This building will store packaged ILW wastes that have arisen over time and will store these wastes until an offsite disposal facility is available. The ILW waste will house packaged radioactive waste in one above ground location, rather than storing waste below ground as it currently occurs at the Berkeley nuclear power station. The project will be carried out in three stages, Construction of the building Operation/filling of the building with packages of ILW. Long term storage of ILW during care and maintenance period until a disposal route becomes available. The technical assessment areas covered by the environmental impact statement are as follows- Air quality and dust Archaeology and cultural heritage Ecology Geology, hydrology and soils Noise and vibration Surface waters Traffic and transport. (Gloucestershire country 2007) SECTION 3 3.1 THE USE OF RISK ASSESSMENT IN EACH EIA 3.2 METHODOLOGY USED FOR ASSESSMENT IN EIS The methodology of analysis of impact should be taken into consideration when comparing the two EIS used for this study bearing in mind that the case studies are from different industrial sectors. Berkeley nuclear power plant is a high risk and high profile project and it deals with radioactive waste (although the radioactive waste is solid and there is no emission to air). Westbury bypass on the other hand is low risk low profile project with significant impact on air quality (rise in dust particulate matter and oxides of nitrogen) during the construction phase and emissions from vehicles after construction. Method of analysis of impacts- Case A The following methods were used in the analysis of local effects Qualitative and quantitative assessment used to analyze air quality. Dispersion model selection(air quality strategy) Meteorology Sensitive receptors Short term mean concentrations Method of analysis for case-B Simple qualitative to complex quantitative method was used to analyze air quality The use of scientific criteria Comparison of predicted changes with established national and international air quality standards, objectives and thresholds. Interpretation of planning and other environmental policies for example, the assessment of whether the predicted change will conflict the objectives of an air quality management area. Review of comparable proposals on environment. The NSCA flow chart -Event tree analysis Generic assessment methodology. Though the methodology used for risk assessment is similar, the event tree analysis which was used in case study B was absent in case study A. SECTION 4 4.1 POTENTIAL FOR IMPROVING OR EXTENDING EIA EIA have emphasized possible impact on natural ecosystems and, to some extent, human communities but have paid no attention to health effect of other risks (Beanlands 1984a, Clark 1984a and Giroult 1984a). More precisely, even for impacts whose ultimate significance might involve health, such as air pollution, EIA studies typically predict only the environmental fate of contaminants, rather than the effect on health itself and RA have emphasized human health effects, especially potential mortality due to cancer or technological catastrophes. (Andrews 1995) The stages of RA were incorporated into both case studies, but RA was not carried out extensively especially in the Berkeley nuclear power station case. It is recommended that a separate section concerned with health risk assessment be prepared within the EIS for high risk and high profile projects but it was absent in this case. There was failure to conduct probability assessment (uncertainty analysis) in case of the unforeseen accidents like explosions or unplanned discharge of radioactive solid waste into the environment. Risk =probability (likelihood or chance that harm will occur) ÃÆ'- consequence (nature of the harm that can occur). There was also no mitigation plans in case of an accident, if there was, then it was not included in the EIS. Risk communication was also absent in both case studies. Also the dose response or exposure assessment which measures the intensity, frequency and duration of human exposure to an agent was present for case A, (Extrapolation dose response methodology) but the effects of the dose for air quality pollutants in case B was not analyzed properly. Hazard index calculation for non carcinogens was absent. HAZOP analysis carried out in case A but absent in case B. Source-pathway-receptor identified in case A, but only source and receptor identified in case B. Risk-benefit analysis also absent. Including the omitted RA analyses above would have improved the use of RA in these EIAs SECTION 5 5.1 CONCLUSION/ RECOMMENDATIONS Many actions need both EIA and RA assessment. In these instances, a more useful analysis would be obtained from combining the two. (Andrews 1995) The aim of this report has been to evaluate how environmental/health RA were used in different stages of the two reviewed EISs, and point out how possible ways that RA might have played a greater role. Systematic application of RA in accordance to best practice was not observed. For a better Incorporation of RA into EIA, there should be emphasis on emergency response measures in the event of accidents and associated environmental perturbations. Canter (1993). REFERENCES Wiltshire County Council, (2007) A350 Westbury bypass Environmental Impact Statement 2007. Trowbridge, Wiltshire County Council. Gloucestershire County council (2007) Berkeley ILW Store. Environmental Impact Statement Issue 1 Gloucester. Gloucestershire County Council. Andrews,R.N.C (1995) Environmental Impact Assessment and Risk Assessment: Learning from each other, In P Wathern (Ed)Environmental impact Assessment: Theory and Practice (Routledge/London) Brookes, A. (2001) Environmental Risk Assessment and Risk management, in P. Morris and R Therivel (Eds) Methods of Environmental Impact Assessment, 2nd Edition(Spon Press/London) Eduljee, G (1999), Risk Assessment in Petts, J. (Ed), Handbook of Environmental Impact Assessment, Volume 1, Process, Methods and Potential, Blackwell Science, London Demidova, O and A Cherp (2005), ââ¬Å"Risk assessment for improved treatment of health considerations in EIAâ⬠Environmental Impact Assessment Review 2(4), page 411-429. Canter, L. W (1993) ââ¬Å"Pragmatic Suggestions of Incorporating Risk Assessment Principles in EIA studiesâ⬠. Environmental Professional, 15(1), Page 125-138.
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