976 resultados para environmental cost
Resumo:
On cover: Water quality management.
Resumo:
"December, 1980."
Resumo:
"ILENR/BE-87/01."
Resumo:
There exists a major cost issue as regards termite damage to wooden structures. A factor in this cost has been the increasing trend towards slab-on-ground construction. Current literature has been reviewed in relation to concerns about the possible public/environmental health consequences of the repeated use of termiticides in large quantities. The previous, current and projected future use patterns of termiticides are reviewed in the context of techniques appropriate for termite control and treatment priorities. The phasing out of organochlorine termiticides in Australia was undertaken to minimise impact of these substances on the environment and to a lesser extent on public health. These persistent chemicals were replaced by substances with high activity but relatively low persistence in the soil. There has also been an increase in the use of alternative methods (e.g. physical barriers) for the control of termites. The transition away from organochlorine termiticides has led to a realisation that significant information gaps exist with regard to replacement chemicals and other technologies. Although relatively persistent, the organochlorine chemicals have a limited lifespan in soils. Their concentrations are gradually attenuated by processes such as transport away from the point of application and biodegradation. Wooden structures originally treated with these substances will, with the passing of time, be at risk of termite infestation. The only available option is re-treatment with chemicals currently registered for termite control. Thus, there are likely to be substantial future increases associated with the cost of re-treatment and repairs of older slab-on-ground dwellings. More information is required on Australian termite biology, taxonomy and ecology. The risks of termite infestation need to be evaluated, both locally and nationally so that susceptible or high risk areas, structures and building types can be identified and preventive measures taken in terms of design and construction. Building regulations and designs need to be able to reduce or eliminate high-risk housing; and eliminate or reduce conditions that are attractive to termites and/or facilitate termite infestation.
Resumo:
In wastewater treatment plants with anaerobic sludge digestion, 15-20% of the nitrogen load is recirculated to the main stream with the return liquors from dewatering. Separate treatment of this ammonium-rich digester supernatant significantly reduces the nitrogen load of the activated sludge system. Two biological applications are considered for nitrogen elimination: (i) classical autotrophic nitrification/heterotrophic denitrification and (ii) partial nitritation/autotrophic anaerobic ammonium oxidation (anammox). With both applications 85-90% nitrogen removal can be achieved, but there are considerable differences in terms of sustainability and costs. The final gaseous products for heterotrophic denitrification are generally not measured and are assumed to be nitrogen gas (N-2). However, significant nitrous oxide (N2O) production can occur at elevated nitrite concentrations in the reactor. Denitrification via nitrite instead of nitrate has been promoted in recent years in order to reduce the oxygen and the organic carbon requirements. Obviously this achievement turns out to be rather disadvantageous from an overall environmental point of view. On the other hand no unfavorable intermediates are emitted during anaerobic ammonium oxidation. A cost estimate for both applications demonstrates that partial nitritation/anammox is also more economical than classical nitrification/denitrification. Therefore autotrophic nitrogen elimination should be used in future to treat ammonium-rich sludge liquors.
Resumo:
The paper presents a spreadsheet-based multiple account framework for cost-benefit analysis which incorporates all the usual concerns of cost-benefit analysts such as shadow-pricing to account for market failure. distribution of net benefits. sensitivity and risk analysis, cost of public funds, and environmental effects. The approach is generalizable to a wide range of projects and situations and offers a number of advantages to both analysts and decision-makers, including transparency, a check on internal consistency, and a detailed summary of project net benefits disaggregated by stakeholder group. Of particular importance is the ease with which this framework allows for a project to be evaluated from alternative decision-making perspectives and under alternative policy scenarios where the trade-offs among the project's stakeholders can readily be identified and quantified. (C) 2004 Elsevier Ltd. All rights reserved.
Resumo:
Background: Costs of tobacco-related disease can be useful evidence to support tobacco control. In Hong Kong we now have locally derived data on the risks of smoking, including passive smoking. Aim: To estimate the health-related costs of tobacco from both active and passive smoking. Methods: Using local data, we estimated active and passive smoking-attributable mortality, hospital admissions, outpatient, emergency and general practitioner visits for adults and children, use of nursing homes and domestic help, time lost from work due to illness and premature mortality in the productive years. Morbidity risk data were used where possible but otherwise estimates based on mortality risks were used. Utilisation was valued at unit costs or from survey data. Work time lost was valued at the median wage and an additional costing included a value of US$1.3 million for a life lost. Results: In the Hong Kong population of 6.5 million in 1998, the annual value of direct medical costs, long term care and productivity loss was US$532 million for active smoking and US$156 million for passive smoking; passive smoking accounted for 23% of the total costs. Adding the value of attributable lives lost brought the annual cost to US$9.4 billion. Conclusion: The health costs of tobacco use are high and represent a net loss to society. Passive smoking increases these costs by at least a quarter. This quantification of the costs of tobacco provides strong motivation for legislative action on smoke-free areas in the Asia Pacific Region and elsewhere.
Resumo:
An integrated anaerobic-aerobic treatment system of sulphate-laden wastewater was proposed here to achieve low sludge production, low energy consumption and effective sulphide control. Before integrating the whole system, the feasibility of autotrophic denitrification utilising dissolved sulphide produced during anaerobic treatment of sulphate rich wastewater was studied here. An upflow anaerobic sludge blanket reactor was operated to treat sulphate-rich synthetic wastewater (TOC = 100 mg/L and sulphate = 500 mg/L) and its effluent with dissolved sulphide and external nitrate solution were fed into an anoxic biofilter. The anaerobic reactor was able to remove 77-85% of TOC at HRT of 3 h and produce 70-90 mg S/L sulphide in dissolved form for the subsequent denitrification. The performance of anoxic reactor was stable, and the anoxic reactor could remove 30 mg N/L nitrate at HRT of 2 h through autotrophic denitrification. Furthermore, sulphur balance for the anoxic filter showed that more than 90% of the removed sulphide was actually oxidised into sulphate, thereby there was no accumulation of sulphur particles in the filter bed. The net sludge productions were approximately 0.15 to 0.18 g VSS/g COD in the anaerobic reactor and 0.22 to 0.31 g VSS/g NO3--N in the anoxic reactor. The findings in this study will be helpful in developing the integrated treatment system to achieve low-cost excess sludge minimisation.
Resumo:
After the ten Regional Water Authorities (RWAs) of England and Wales were privatized in November 1989, the successor Water and Sewerage Companies (WASCs) faced a new regulatory regime that was designed to promote economic efficiency while simultaneously improving drinking water and environmental quality. As legally mandated quality improvements necessitated a costly capital investment programme, the industry's economic regulator, the Office of Water Services (Ofwat), implemented a retail price index (RPI)+K pricing system, which was designed to compensate the WASCs for their capital investment programme while also encouraging gains in economic efficiency. In order to analyse jointly the impact of privatization, as well as the impact of increasingly stringent economic and environmental regulation on the WASCs' economic performance, this paper estimates a translog multiple output cost function model for the period 1985–1999. Given the significant costs associated with water quality improvements, the model is augmented to include the impact of drinking water quality and environmental quality on total costs. The model is then employed to determine the extent of scale and scope economies in the water and sewerage industry, as well as the impact of privatization and economic regulation on economic efficiency.
Resumo:
A környezeti kockázatok megfelelő felmérése és kezelése napjaink egyik legfontosabb kérdése, nemcsak a szakmai, hanem a széles értelemben vett közvélemény számára. A szerző cikkében azt vizsgálja, hogy a környezeti kockázatok felmérésének milyen megközelítései vannak. Kulcskérdésként pedig arra koncentrál, hogy a kockázatkezelési döntéseket hogyan befolyásolja a becslések bizonytalansága. Először a környezeti kockázat definícióját adja meg, majd azt mutatja be, hogy a környezeti kockázatok kezelésére vonatkozó megközelítések milyen párhuzamban állnak a pénzügyi rendszerrel, mint komplex rendszerre vonatkozó megközelítésekkel. Végül a jelenleg legnagyobb kockázatoknak tartott környezeti kockázatokat ismerteti röviden. A cikk második részében kockázatkezelési alternatívákat mutat be, és azt, hogy a kockázatkezelési lépések kiválasztását befolyásolja a bizonytalanság. Ezt illusztrálandó Brouwer-Blois (2008) modelljét használva a soklépéses szimulációt és alternatív döntési kritériumot – a kritikus (extrém) költség-hatás mutatót – alkalmazza. _____________ Adequate assessment and management of environmental risks is a key question nowadays also for professional experts and also for the overall public. In this article the author examines the different approaches concerning environmental risks. He concentrates as a key question the influence on risk management decisions of uncertainties raised by our estimations. First he analyses the definition of environmental risks, and he shows the similarities and differences between approaches concerning environmental risks and risks threatening financial system, and finally he gives short overview on the most current environmental risks. In the second part of the paper he presents risk management alternatives and analyses the influential power of uncertainty on risk management decisions. In order to illustrate this phenomenon the author applies the model of Brouwer-Blois (2008) with multistep simulation and an alternative decisive criterion, the ranking based on critical (extreme) cost to effect measure.
Resumo:
Global warming16 has already begun. Climate change has become a self-propelling and self-reinforcing process as a result of the externality associated with greenhouse- gas (GHG) emissions. Although it is an externality related to humankind, according to a number of unique features we should distinguish it from other externalities. Climate change is a global phenomenon in its causes and consequences. The long-term and persistent impacts of climate change will likely continue over centuries without further anthropogenic mechanism. The preindustrial (equilibrium) level of GHG concentration in the atmosphere cannot be restored since it is irreversible, but if we do not stabilise the actual level of atmospheric concentration, the situation will become much worse than it is now. Assessing the impacts of climate change requires careful considerations because of the pervasive uncertainties and risks associated with it.
Resumo:
This paper examines the methodological aspect of climate change, particularly the aggregation of costs and benefits induced by climate change on individuals, societies, economies and on the whole ecosystem. Assessing the total and/or marginal costs of environmental change is difficult because of wide range of factors that have to be involved. The subsequent study tries to capture the complexity of cost assessment on climate change therefore includes several critical factors such as scenarios and modeling, valuation and estimation, equity and discounting.
Resumo:
This dissertation is about the research carried on developing an MPS (Multipurpose Portable System) which consists of an instrument and many accessories. The instrument is portable, hand-held, and rechargeable battery operated, and it measures temperature, absorbance, and concentration of samples by using optical principles. The system also performs auxiliary functions like incubation and mixing. This system can be used in environmental, industrial, and medical applications. ^ Research emphasis is on system modularity, easy configuration, accuracy of measurements, power management schemes, reliability, low cost, computer interface, and networking. The instrument can send the data to a computer for data analysis and presentation, or to a printer. ^ This dissertation includes the presentation of a full working system. This involved integration of hardware and firmware for the micro-controller in assembly language, software in C and other application modules. ^ The instrument contains the Optics, Transimpedance Amplifiers, Voltage-to-Frequency Converters, LCD display, Lamp Driver, Battery Charger, Battery Manager, Timer, Interface Port, and Micro-controller. ^ The accessories are a Printer, Data Acquisition Adapter (to transfer the measurements to a computer via the Printer Port and expand the Analog/Digital conversion capability), Car Plug Adapter, and AC Transformer. This system has been fully evaluated for fault tolerance and the schemes will also be presented. ^
Resumo:
The first essay developed a respondent model of Bayesian updating for a double-bound dichotomous choice (DB-DC) contingent valuation methodology. I demonstrated by way of data simulations that current DB-DC identifications of true willingness-to-pay (WTP) may often fail given this respondent Bayesian updating context. Further simulations demonstrated that a simple extension of current DB-DC identifications derived explicitly from the Bayesian updating behavioral model can correct for much of the WTP bias. Additional results provided caution to viewing respondents as acting strategically toward the second bid. Finally, an empirical application confirmed the simulation outcomes. The second essay applied a hedonic property value model to a unique water quality (WQ) dataset for a year-round, urban, and coastal housing market in South Florida, and found evidence that various WQ measures affect waterfront housing prices in this setting. However, the results indicated that this relationship is not consistent across any of the six particular WQ variables used, and is furthermore dependent upon the specific descriptive statistic employed to represent the WQ measure in the empirical analysis. These results continue to underscore the need to better understand both the WQ measure and its statistical form homebuyers use in making their purchase decision. The third essay addressed a limitation to existing hurricane evacuation modeling aspects by developing a dynamic model of hurricane evacuation behavior. A household's evacuation decision was framed as an optimal stopping problem where every potential evacuation time period prior to the actual hurricane landfall, the household's optimal choice is to either evacuate, or to wait one more time period for a revised hurricane forecast. A hypothetical two-period model of evacuation and a realistic multi-period model of evacuation that incorporates actual forecast and evacuation cost data for my designated Gulf of Mexico region were developed for the dynamic analysis. Results from the multi-period model were calibrated with existing evacuation timing data from a number of hurricanes. Given the calibrated dynamic framework, a number of policy questions that plausibly affect the timing of household evacuations were analyzed, and a deeper understanding of existing empirical outcomes in regard to the timing of the evacuation decision was achieved.