The Importance Of Environmental Risk Assessments Environmental Sciences Essay

The Importance Of environmental Risk Assessments Environmental Sciences EssayEnvironmental peril opinion is an integral part of a project. It is important that a project attributes due weight and consideration to the assessments conclusions, although it is just as dictatorial that an assessment identifies the assessment eat uppoints in devote to determine the application and emolument of the assessment. Dep arresting on the item project, an environmental stake assessment loafer be apply to assist a project to assess strategic and or tactical uncertainties, as well as assisting in making the topper informed decision given the circumstances. (Beer Ziolkowski, 1995, p. 6)Environmental danger assessment is the regale (Joint Technical Committee OB/7 Risk Management, 1999) that analyses, considers and then places into a criterion framework the finds to adult male health, welfare and ecosystems that are the result of unfavourable developmental impacts on the natural enviro nment. (Beer Ziolkowski, 1995) The placement of the foreseeable stakes into a contract criteria, level and/or pre heady standard enables a project to consider, in comparability to the same, what environmental hazards have the greatest potential of occurring, as a result of a specific project, to the selected endpoints and what action (if each) is required. (Joint Technical Committee OB/7 Risk Management, 1999), (Beer Ziolkowski, 1995).The usefulness of environmental luck assessment scum bag depend on what criteria, pre-determined standard and/or level is being utilised as an acceptable comparison. What may be important to one specific environment may non be important to an separate, in that respectfore, it is important, prior to the startle of the environmental assessment, that the environmental values to be protected (Stoklosa), the endpoints are agreed.The vastness of environmental risk assessment as a indispensable dower of a project is evidenced in a recent prophet ic case study commissioned by Alcoa, the worlds largest producer of aluminium (Alcoa Inc.), with complaisance to an aspect of the construction of its proposed aluminium smeltery in East Iceland. (Booth, et al., 2009) (referred to as The aluminum Smelter Study).The aluminum Smelter Study is an example of predictive risk assessment. The study was conducted to determine whether there would be a important difference in the level of risk to human and ecological receptors from constituents in impart dismissals from the aluminium smelter (prior to construction), either with or without crocked scrubbers. (Booth, et al., 2009, p. 423) gassy sacks from the aluminium smelting process are minimized by existing controls, although not all emissions are captured by these basic controls. Prior to the commencement of the study, there was no certainty regarding whether the addition of wet scrubbers to the basic controls would provide any(prenominal) additional benefit as these also introduce an environmental cost. It is necessary for Icelands Permitting permit, if they are to approve the Smelter without the indispensability for the wet scrubbers, that an environmental risk assessment is conducted with the harm for both scenarios, with and without the wet scrubbers, explored in advance, in coif that the authorities can make an informed decision.Although wet scrubbers can in some circumstances control gaseous emissions, the contaminants removed by the scour are transferred into the smelters surround piddle ways, potentially causing harm to the contact ecology and humans alike. For the purpose of the assessment, the selection of the emissions/contaminants present in the smelter region, which may be emitted with or without wet scrubbers, were determined on the prat of what the principal constituents of gaseous emissions from primary aluminium production are. (Booth, et al., 2009, p. 429) These include, fluorides, particulates, sulphur dioxide, one C dioxide, carbo n monoxide, perfluorocarbons and polycyclic aromatic hydrocarbons (PAHs). The design of the smelter and the operational controls already in place were considered prior to depicting the contaminants that may pose a potential risk to the pre-determined endpoints.Whether or not the wet scrubber process will micturate substantial harm to the environment requires a risk assessment of bill the environmental risks of word-painting to humans and the environment to the emissions and waste generated with and without the wet scrubbers. .The environmental endpoints for the purpose of this environmental risk assessment were selected on the basis of a number of criteria, including, amongst others, the ecosystems and species that are present in the Hraun industrial tract and surrounding areas in Ewyarfjorour, Fjardabyggd, on the east coast of Iceland (Booth, et al., 2009, p. 425) in close proximity to the aluminium smelter site. In addition, just endpoints were selected by considering terre strial and leatherneck site studies (which) were conducted (Booth, et al., 2009, p. 425) in the early planning phase and using the reading obtained to determine what plants and animals in the surrounding area could be at risk from the wet scrubber emissions.The human environment endpoints were also assessed, utilising studies completed in the planning stage of the smelter site and its surrounding fiord area. The Aluminium Smelters location in East Iceland presents a unique environment, where there is critical development and, due to both the weather and terrain, a relatively inactive creation level, see puzzle out 1 of Appendix A . The studies assessed the population of the surrounding area, noting that the terrain restricts much human population, the potential exposure pathways (i.e the drinking pee for the residents in the villages is the river Delta and those outside the villages use bore water, neither of which there is any indication the smelter will affect.) and whether the populations source of food will be affected and, in turn, could indirectly expose the human population to harm.The Aluminium Smelter Study measured the harm to both human health and the ecology by developing a number of diametric abstract models to assist in identify(ing) the controlling variables that affect exposure and risk, and to focus the risk assessment process on the most important pathways of potential exposure. (Booth, et al., 2009, p. 430) Figure 2, at paginate 431, is an illustration of a conceptual site model, which assists to identify the exposure pathways from the source, its transport, the media, (i.e air, soil, water) and then the exit on humans and the ecology. In particular, care is directed when electing the endpoints to those plants, animals and humans that are potentially sensitive, or will be at greater risk of exposure, to the emission contaminants as identify as potentially being present. Further consideration must also be directed to ecologically i mportant species and those species having special regulatory status (if appropriate) or social importance. (Booth, et al., 2009, p. 430) If, after having conducted all of the above and considered all the contributing grammatical constituents of the models, a pathway was identified as having a potential to be complete, that factor was then assessed as posing a potential risk to the end pointAlcoa engaged state Tech to conduct the air distribution role model, which was required to assess both the human and ecological risk assessments. communicate dispersion moulding was chosen as the best method, considering the difficult Fjord landscape and complex wind conditions, to determine the effects on the receptors from the wet scrubber and no wet scrubber smelting scenarios. A copy of Earth Techs promulgate is annexed at Appendix B.A copy of Earth Techs report is annexed at Appendix B.A number of air modelling scenarios were simulated in tramp to assess exposure to provide the releva nt basis for comparison to standards that are protective of human health and the environment (Booth, et al., 2009, p. 434). These scenarios are illustrated in Table 2 and the time frames were chosen in order that the results could be compared to the corresponding regulatory limits that are protective of human health.The different environmental values to be protected require different measures of assessment. For example, in order to measure the harm of the risk to plant species in the Fjord, the model requires modelling for annual mean sulphur dioxide (SO2) (one of the identified emissions) exposure as toxicology-based cover values for plants are expressed as annual averages.The results of the dispersion models were exhibited on a geographic power grid. For a more detailed explanation of the grid and a copy of the same, see page 437 (Booth, et al., 2009). (Katie, what does this add?)In order to assess the risk of the estimated air dousings and deposition rates, with or without the effect of saltwater scrubbers, the two scenarios were compared on a point-specific basis or were examined statistically or probabilistically to describe the nature of exposure to each constituent by sensitive receptors.The study not only conducted air modelling exposure modelling, the risk assessment process also utilised previously conducted leatherneck dispersion modelling, which assessed the harm to the Fjord marine ecology, including modelling sediment and the concentration in water of elements such as fluoride, another of the identified end point contaminants.The marine dispersion models were then assessed using data from gain previous studies, as well as data collected from other Alcoa facilities, such as those in Canada and Norway as a means of support the reasonableness of the predictions at Fjord. (Booth, et al., 2009)In addition to the air dispersion modelling and marine dispersion modelling, the risk assessment also assessed the potential perverse effects from sedime nt bound substance and dissolved substances (Booth, et al., 2009, p. 438) from the discharge of water into the Fjord in the situation of the seawater scrubber. The constituents, in particular PAHs (emission of which is normally associated with effluent sediment from the wet scrubber), that were hypothesised to be released into the Fjord, were selected to be assessed. The harm of these constituents (see page 438) was measured by comparing modelled concentrations in sediment and water to procurable perniciousness thresholds and screening benchmarks. (Booth, et al., 2009) Similar modelling was utilised to assess the effect of the scrubber discharge to wildlife, including food web modelling for species that forage on items that could potentially accumulate PAHs. (Booth, et al., 2009). Similarly, the harm to plants was measured by comparing the modelled air emission concentrations of SO2 and fluoride to conservative toxicity thresholds for sensitive plant communities. Further, the risk to vertebrates was determined on the basis of predicted concentrations of fluoride and PAHs (sic) in the diet of herbivorous mammals and birds, based on the EarthTech air modelling results and plant uptake models, and comparing those dietary concentrations to toxicity thresholds developed from the scientific literature. (Booth, et al., 2009, p. 438)There were some limitations in the study on the effect of emissions from the two alternate scrubber scenarios, which are discussed in further detail at page 439. The quantitative results to the identified receptors and the concentration estimates of emission constituents in the air from inhalation exposure were measured to be considered in comparison with all relevant standards, and PAHs (sic) were compared with health-protective screening values for air and soil.In addition to the human risk of inhalation of the emissions, the study also assessed the harm from dermal (skin) contact to humans, one of the identified endpoint pathways. The soil concentrations, in accordance with the model (see page 439), were then compared to well-accepted health-protective soil preliminary remediation goals for BaP and HF developed by USEPA.The potential harm on human health from the discharge of constituents in the air and soil were measured by comparison to elected, accepted benchmarks.Each of the different models required different types of methods to measure the predicted harm. In order that the risk assessment provides the most accurate conclusions that can be relied on for decision making, the different end points required different benchmarks for assessment. For a more detailed assessment of the effect of the identified emission contaminants on the endpoints, see page 439.The results of the modelling predictions on the level of risk to human and ecological receptors indicated that both scenarios produce results that are lower that the identified risk thresholds and, by and large, the risk to all end points was lower for a sme lter without wet scrubbers.Alcoa submitted the results of the environmental risk assessment to the Government of Icelands Permitting Authority and, in turn, the Authority approved an operating permit for the facility without the need to install seawater scrubbers. (Booth, et al., 2009, p. 440) It must be noted that some care must be attributed to the risk assessments findings as it was financed by Alcoa, however a disclaimer appears on page 1 of this study, the opinions expressed are the fissiparous scientific views of the authors (Booth, et al., 2009, p. 423) and it would appear that the Iceland Permitting Authority agrees.The benefit for Alcoa was threefold. Firstly, by successfully obtaining the Iceland Governments permit, they were not required to expend the additional cost of constructing the seawater scrubber. Further, the results of the environmental risk assessment were able to be distributed to the local community, assisting Alcoa in continuing to defend its duties to th e people of the area faithfully. (Alcoa Inc.) Finally, Alcoa have utilised the environmental risk assessment to demonstrate the long-term sustainability of operations, as well as environmental protectiveness. (Booth, et al., 2009, p. 440). The training obtained from the environmental risk assessment process was a necessary component part of Alcoas aluminium smelter Iceland project.