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- Environmental impacts on soil and groundwater at airports: origin, contaminants of concern and environmental risksPublication . Nunes, L.; Zhu, Y.-G.; Stigter, T. Y.; Monteiro, José Paulo; Ribau Teixeira, MargaridaEnvironmental impacts of airports are similar to those of many industries, though their operations expand over a very large area. Most international impact assessment studies and environmental management programmes have been giving less focus on the impacts to soil and groundwater than desirable. This may be the result of the large attention given to air and noise pollution, relegating other environmental descriptors to a second role, even when the first are comparatively less relevant. One reason that contributes to such ‘‘biased’’ evaluation is the lack of systematic information about impacts to soil and groundwater from airport activities, something the present study intends to help correct. Results presented here include the review of over seven hundred documents and online databases, with the objective of obtaining the following information to support environmental studies: (i) which operations are responsible for chemical releases?; (ii) where are these releases located?; (iii) which contaminants of concern are released?; (iv) what are the associated environmental risks? Results showed that the main impacts occur as a result of fuel storage, stormwater runoff and drainage systems, fuel hydrant systems, fuel transport and refuelling, atmospheric deposition, rescue and fire fighting training areas, winter operations, electrical substations, storage of chemical products by airport owners or tenants, and maintenance of green areas. A new method for ranking environmental risks of organic substances, based on chemical properties, is proposed and applied. Results show that the contaminants with the highest risks are the perfluorochemicals, benzene, trichloroethylene and CCl4.
- Recursos hídricosPublication . Cunha, Luís V.; Ribeiro, Luís; Oliveira, Ricardo P.; Nascimento, João; Monteiro, José Paulo; Dill, Amélia Maria Mello de Carvalho; Nunes, L.O Projecto "Climate Change in Portugal. Scenarios, Impacts and Adaptation Measures" (SIAM) iniciou-se em meados de 1999, com o financiamento da Fundação Calouste Gulbenkian e da Fundação para a Ciência e a Tecnologia. O Projecto SIAM teve como objectivo a realização da primeira avaliação integrada dos impactos e medidas de adaptação às alterações climáticas em Portugal Continental no século XXI. Os estudos realizados basearam-se em cenários do clima futuro obtidos a partir de modelos de circulação geral da atmosfera e incidiram sobre um conjunto de sectores sócio-económicos e sistemas biofísicos designadamente: recursos hídricos, zonas costeiras, agricultura, saúde humana, energia, florestas e biodiversidade e pescas. Foi também realizada uma análise sociológica sobre a problemática das alterações climáticas em Portugal. As principais conclusões obtidas no Projecto SIAM foram publicadas num Sumário Executivo e Conclusões, lançado em Outubro de 2001, editado em português e em inglês.A segunda fase do Projecto SIAM (SIAM II) iniciou-se em Janeiro de 2002. Esta segunda fase focou-se no estudo de caso do Estuário do Sado, tendo os estudos sido alargados às Regiões Autónomas da Madeira e dos Açores. O SIAM II incluiu ainda uma componente de Outreach que teve como objectivo a divulgação dos resultados obtidos no SIAM I aos diversos agentes interessados, obtendo ainda inputs para o SIAM II, através da organização de reuniões nas quais participaram as equipas dos sectores considerados relevantes para a região escolhida e os respectivos agentes interessados. O SIAM II foi financiado pelo Instituto do Ambiente, do Ministério das Cidades, do Ordenamento do Território e Ambiente.
- OPTEXPLOR – new application for water resources management for private water supply utilitiesPublication . Nunes, L.; Monteiro, José Paulo; Stigter, T. Y.; Ribau Teixeira, Margarida; Nascimento, João; Ribeiro, L.; Lucas, HelenaThis article presents the steps made for the development of a new water management system (WMS) for a private water utility in the south of Portugal, and its main results. The WMS is composed of a set of models representing the water resources, surface and groundwater, water quality models, economic models, and water allocation optimization models. The system was developed at the request of the regional water utility (Águas do Algarve, S.A.), which is responsible for distributing water to the entire Algarve region (most touristic area in Portugal, with about ten million tourists per year, and a local population of about four hundred thousand). Results clearly show that independently of the amount of water available, inter-annual exploration is always the best solution, if possible. When water scarcity is high, as in consecutive dry years, the water utility will need to call municipalities to use their systems to complement supply. The level of supply deficit is higher, in any case, for annual exploration management, and so are exploration costs. These results clearly show that water resources management needs careful inter-annual planning, even for a private water supply utility with very limited control over water exploration by other competing users.
- Screening of sustainable groundwater sources for integration into a regional drought-prone water supply systemPublication . Stigter, T. Y.; Monteiro, José Paulo; Nunes, L.; Vieira, João; Cunha, Maria da Conceição; Ribeiro, Luís; Nascimento, João; Lucas, HelenaThis paper reports on the qualitative and quantitative screening of groundwater sources for integration into the public water supply system of the Algarve, Portugal. The results are employed in a decision support system currently under development for an integrated water resources management scheme in the region. Such a scheme is crucial for several reasons, including the extreme seasonal and annual variations in rainfall, the effect of climate change on more frequent and long-lasting droughts, the continuously increasing water demand and the high risk of a single-source water supply policy. The latter was revealed during the severe drought of 2004 and 2005, when surface reservoirs were depleted and the regional water demand could not be met, despite the drilling of emergency wells. For screening and selection, quantitative criteria are based on aquifer properties and well yields, whereas qualitative criteria are defined by water quality indices. These reflect the well’s degree of violation of drinking water standards for different sets of variables, including toxicity parameters, nitrate and chloride, iron and manganese and microbiological parameters. Results indicate the current availability of at least 1100 l s−1 of high quality groundwater (55% of the regional demand), requiring only disinfection (900 l s−1) or basic treatment, prior to human consumption. These groundwater withdrawals are sustainable when compared to mean annual recharge, considering that at least 40% is preserved for ecological demands. A more accurate and comprehensive analysis of sustainability is performed with the help of steady-state and transient groundwater flow simulations, which account for aquifer geometry, boundary conditions, recharge and discharge rates, pumping activity and season. (tibor.stigter@ist.utl.pt) ality. They permit an advanced analysis of present and future scenarios and show that increasing water demands and decreasing rainfall will make the water supply system extremely vulnerable, with a high risk of groundwater salinization and ecosystem degradation.