Roebeling, P C; Cunha, M C; Arroja, L; van Grieken, M E
2015-01-01
Marine ecosystems are affected by water pollution originating from coastal catchments. The delivery of water pollutants can be reduced through water pollution abatement as well as water pollution treatment. Hence, sustainable economic development of coastal regions requires balancing of the marginal costs from water pollution abatement and/or treatment and the associated marginal benefits from marine resource appreciation. Water pollution delivery reduction costs are, however, not equal across abatement and treatment options. In this paper, an optimal control approach is developed and applied to explore welfare maximizing rates of water pollution abatement and/or treatment for efficient diffuse source water pollution management in terrestrial-marine systems. For the case of diffuse source dissolved inorganic nitrogen water pollution in the Tully-Murray region, Queensland, Australia, (agricultural) water pollution abatement cost, (wetland) water pollution treatment cost and marine benefit functions are determined to explore welfare maximizing rates of water pollution abatement and/or treatment. Considering partial (wetland) treatment costs and positive water quality improvement benefits, results show that welfare gains can be obtained, primarily, through diffuse source water pollution abatement (improved agricultural management practices) and, to a minor extent, through diffuse source water pollution treatment (wetland restoration).
Peed, Lindsay A; Nietch, Christopher T; Kelty, Catherine A; Meckes, Mark; Mooney, Thomas; Sivaganesan, Mano; Shanks, Orin C
2011-07-01
Diffuse sources of human fecal pollution allow for the direct discharge of waste into receiving waters with minimal or no treatment. Traditional culture-based methods are commonly used to characterize fecal pollution in ambient waters, however these methods do not discern between human and other animal sources of fecal pollution making it difficult to identify diffuse pollution sources. Human-associated quantitative real-time PCR (qPCR) methods in combination with low-order headwatershed sampling, precipitation information, and high-resolution geographic information system land use data can be useful for identifying diffuse source of human fecal pollution in receiving waters. To test this assertion, this study monitored nine headwatersheds over a two-year period potentially impacted by faulty septic systems and leaky sanitary sewer lines. Human fecal pollution was measured using three different human-associated qPCR methods and a positive significant correlation was seen between abundance of human-associated genetic markers and septic systems following wet weather events. In contrast, a negative correlation was observed with sanitary sewer line densities suggesting septic systems are the predominant diffuse source of human fecal pollution in the study area. These results demonstrate the advantages of combining water sampling, climate information, land-use computer-based modeling, and molecular biology disciplines to better characterize diffuse sources of human fecal pollution in environmental waters.
NASA Astrophysics Data System (ADS)
Zhang, Yong; Sun, HongGuang; Lu, Bingqing; Garrard, Rhiannon; Neupauer, Roseanna M.
2017-09-01
Backward models have been applied for four decades by hydrologists to identify the source of pollutants undergoing Fickian diffusion, while analytical tools are not available for source identification of super-diffusive pollutants undergoing decay. This technical note evaluates analytical solutions for the source location and release time of a decaying contaminant undergoing super-diffusion using backward probability density functions (PDFs), where the forward model is the space fractional advection-dispersion equation with decay. Revisit of the well-known MADE-2 tracer test using parameter analysis shows that the peak backward location PDF can predict the tritium source location, while the peak backward travel time PDF underestimates the tracer release time due to the early arrival of tracer particles at the detection well in the maximally skewed, super-diffusive transport. In addition, the first-order decay adds additional skewness toward earlier arrival times in backward travel time PDFs, resulting in a younger release time, although this impact is minimized at the MADE-2 site due to tritium's half-life being relatively longer than the monitoring period. The main conclusion is that, while non-trivial backward techniques are required to identify pollutant source location, the pollutant release time can and should be directly estimated given the speed of the peak resident concentration for super-diffusive pollutants with or without decay.
Diffuse sources of human fecal pollution allow for the direct discharge of waste into receiving waters with minimal or no treatment. Traditional culture-based methods are commonly used to characterize fecal pollution in ambient waters, however these methods do not discern between...
Non-point source pollution is a diffuse source that is difficult to measure and is highly variable due to different rain patterns and other climatic conditions. In many areas, however, non-point source pollution is the greatest source of water quality degradation. Presently, stat...
A stress ecology framework for comprehensive risk assessment of diffuse pollution.
van Straalen, Nico M; van Gestel, Cornelis A M
2008-12-01
Environmental pollution is traditionally classified as either localized or diffuse. Local pollution comes from a point source that emits a well-defined cocktail of chemicals, distributed in the environment in the form of a gradient around the source. Diffuse pollution comes from many sources, small and large, that cause an erratic distribution of chemicals, interacting with those from other sources into a complex mixture of low to moderate concentrations over a large area. There is no good method for ecological risk assessment of such types of pollution. We argue that effects of diffuse contamination in the field must be analysed in the wider framework of stress ecology. A multivariate approach can be applied to filter effects of contaminants from the many interacting factors at the ecosystem level. Four case studies are discussed (1) functional and structural properties of terrestrial model ecosystems, (2) physiological profiles of microbial communities, (3) detritivores in reedfield litter, and (4) benthic invertebrates in canal sediment. In each of these cases the data were analysed by multivariate statistics and associations between ecological variables and the levels of contamination were established. We argue that the stress ecology framework is an appropriate assessment instrument for discriminating effects of pollution from other anthropogenic disturbances and naturally varying factors.
NASA Astrophysics Data System (ADS)
Ulfah, S.; Awalludin, S. A.; Wahidin
2018-01-01
Advection-diffusion model is one of the mathematical models, which can be used to understand the distribution of air pollutant in the atmosphere. It uses the 2D advection-diffusion model with time-dependent to simulate air pollution distribution in order to find out whether the pollutants are more concentrated at ground level or near the source of emission under particular atmospheric conditions such as stable, unstable, and neutral conditions. Wind profile, eddy diffusivity, and temperature are considered in the model as parameters. The model is solved by using explicit finite difference method, which is then visualized by a computer program developed using Lazarus programming software. The results show that the atmospheric conditions alone influencing the level of concentration of pollutants is not conclusive as the parameters in the model have their own effect on each atmospheric condition.
Todorovic, Zorica; Breton, Neil P
2014-01-01
Sustainable drainage systems (SUDS) offer many benefits that traditional solutions do not. Traditional approaches are unable to offer a solution to problems of flood management and water quality. Holistic consideration of the wide range of benefits from SUDS can result in advantages such as improved flood resilience and water quality enhancement through consideration of diffuse pollution sources. Using a geographical information system (GIS) approach, diffuse pollutant sources and opportunities for SUDS are easily identified. Consideration of potential SUDS locations results in source, site and regional controls, leading to improved water quality (to meet Water Framework Directive targets). The paper will discuss two different applications of the tool, the first of which is where the pollutant of interest is known. In this case the outputs of the tool highlight and isolate the areas contributing the pollutants and suggest the adequate SUDS measures to meet the required criteria. The second application is where the tool identifies likely pollutants at a receiving location, and SUDS measures are proposed to reduce pollution with assessed efficiencies.
NASA Technical Reports Server (NTRS)
Burns, R. E.
1973-01-01
The problem with predicting pollutant diffusion from a line source of arbitrary geometry is treated. The concentration at the line source may be arbitrarily varied with time. Special attention is given to the meteorological inputs which act as boundary conditions for the problem, and a mixing layer of arbitrary depth is assumed. Numerical application of the derived theory indicates the combinations of meteorological parameters that may be expected to result in high pollution concentrations.
de Lima Barros, Alessandra Maciel; do Carmo Sobral, Maria; Gunkel, Günter
2013-01-01
Emissions of pollutants and nutrients are causing several problems in aquatic ecosystems, and in general an excess of nutrients, specifically nitrogen and phosphorus, is responsible for the eutrophication process in water bodies. In most developed countries, more attention is given to diffuse pollution because problems with point pollution have already been solved. In many non-developed countries basic data for point and diffuse pollution are not available. The focus of the presented studies is to quantify nutrient emissions from point and diffuse sources in the Ipojuca river basin, Pernambuco State, Brazil, using the Moneris model (Modelling Nutrient Emissions in River Systems). This model has been developed in Germany and has already been implemented in more than 600 river basins. The model is mainly based on river flow, water quality and geographical information system data. According to the Moneris model results, untreated domestic sewage is the major source of nutrients in the Ipojuca river basin. The Moneris model has shown itself to be a useful tool that allows the identification and quantification of point and diffuse nutrient sources, thus enabling the adoption of measures to reduce them. The Moneris model, conducted for the first time in a tropical river basin with intermittent flow, can be used as a reference for implementation in other watersheds.
Xu, Xianghua; Zhao, Yongcun; Zhao, Xiaoyan; Wang, Yudong; Deng, Wenjing
2014-10-01
The rapid industrialization and urbanization in developing countries have increased pollution by heavy metals, which is a concern for human health and the environment. In this study, 230 surface soil samples (0-20cm) were collected from agricultural areas of Jiaxing, a rapidly industrializing area in the Yangtze Delta of China. Sequential Gaussian simulation (SGS) and multivariate factorial kriging analysis (FKA) were used to identify and explore the sources of heavy metal pollution for eight metals (Cu, Zn, Pb, Cr, Ni, Cd, Hg and As). Localized hot-spots of pollution were identified for Cu, Zn, Pb, Cr, Ni and Cd with area percentages of 0.48 percent, 0.58 percent, 2.84 percent, 2.41 percent, 0.74 percent, and 0.68 percent, respectively. The areas with Hg pollution covered approximately 38 percent whereas no potential pollution risk was found for As. The soil parent material and point sources of pollution had significant influences on Cr, Ni, Cu, Zn and Cd levels, except for the influence of agricultural management practices also accounted for micro-scale variations (nugget effect) for Cu and Zn pollution. Short-range (4km) diffusion processes had a significant influence on Cu levels, although they did not appear to be the dominant sources of Zn and Cd variation. The short-range diffusion pollution arising from current and historic industrial emissions and urbanization, and long-range (33km) variations in soil parent materials and/or diffusion jointly determined the current concentrations of soil Pb. The sources of Hg pollution risk may be attributed to the atmosphere deposition of industrial emission and historical use of Hg-containing pesticides. Copyright © 2014 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Buskirk, E. Drannon, Jr.
Nonpoint sources of pollution have diffuse origins and are major contributors to water quality problems in both urban and rural areas. Addressed in this instructor's manual are the identification, assessment, and management of nonpoint source pollutants resulting from mining, agriculture, and forestry. The unit, part of the Working for Clean Water…
Influence of Diffused Sourcers of Water Pollution In The Basin of Volga River
NASA Astrophysics Data System (ADS)
Vasilchenco, O.
The intensive development of industry and agriculture, great growth of cities in the last decades result in an increase of the nature water consumption and deterioration. Different anthropogenic load change characteristics of water objects regime and de- pletion and qualitative degradation of water resources. Sources of pollution are divided on two classes: controlled and uncontrolled. The first includes industrial and domestic wastewater disposal. Their discharge and concentration of pollutants are quite stable. These sources of pollution are identified as "point". Surface run-off from of cities, industrial platforms, agricultural object, navigation, recreation are not controlled have dispersed nature and are identification as diffuse. Pollution from such sources is es- timates by computation. Quantitative assumption of pollution amounts reaches water objects is complicated and independent problem. The significant amount of full-scale observations and information processes of concerning dissolved and fluidized frag- ments movement are required. According to available guidelines the part of the pollu- tant entering water objects, is about 1-10For estimation of pollution mass and transport are mathematical modeling. Preliminary calculations of contaminants transport for different territories under an- thropogenic impact of river-Volga basin were made either for point sources of pol- lution or for non-point. Received data made it possible to analyze the correlation of contaminant volumes, coming from different sources pollution.
Treatability Aspects of Urban Stormwater Stressors
Eleven years into the 21st century, pollution from diffuse sources (pollution from contaminants picked up and carried into surface waters by stormwater runoff) remains the nation's largest source of water quality problems. Scientists and engineers still seek solutions that will ...
Treatability Aspects of Urban Stormwater Stressors - journal
Eleven years into the 21st century, pollution from diffuse sources (pollution from contaminants picked up and carried into surface waters by stormwater runoff) remains the nation's largest source of water quality problems. Scientists and engineers still seek solutions that will a...
Treatability Aspects of Urban Stormwater Stressors - paper
Eleven years into the 21st century, pollution from diffuse sources (pollution from contaminants picked up and carried into surface waters by stormwater runoff) remains the nation's largest source of water quality problems. Scientists and engineers still seek solutions that will a...
NASA Astrophysics Data System (ADS)
Strahm, Ivo; Munz, Nicole; Braun, Christian; Gälli, René; Leu, Christian; Stamm, Christian
2014-05-01
Water quality in the Swiss river network is affected by many micropollutants from a variety of diffuse sources. This study compares, for the first time, in a comprehensive manner the diffuse sources and the substance groups that contribute the most to water contamination in Swiss streams and highlights the major regions for water pollution. For this a simple but comprehensive model was developed to estimate emission from diffuse sources for the entire Swiss river network of 65 000 km. Based on emission factors the model calculates catchment specific losses to streams for more than 15 diffuse sources (such as crop lands, grassland, vineyards, fruit orchards, roads, railways, facades, roofs, green space in urban areas, landfills, etc.) and more than 130 different substances from 5 different substance groups (pesticides, biocides, heavy metals, human drugs, animal drugs). For more than 180 000 stream sections estimates of mean annual pollutant loads and mean annual concentration levels were modeled. This data was validated with a set of monitoring data and evaluated based on annual average environmental quality standards (AA-EQS). Model validation showed that the estimated mean annual concentration levels are within the range of measured data. Therefore simulations were considered as adequately robust for identifying the major sources of diffuse pollution. The analysis depicted that in Switzerland widespread pollution of streams can be expected. Along more than 18 000 km of the river network one or more simulated substances has a concentration exceeding the AA-EQS. In single stream sections it could be more than 50 different substances. Moreover, the simulations showed that in two-thirds of small streams (Strahler order 1 and 2) at least one AA-EQS is always exceeded. The highest number of substances exceeding the AA-EQS are in areas with large fractions of arable cropping, vineyards and fruit orchards. Urban areas are also of concern even without considering wastewater treatment plants. Only a small number of problematic substances are expected from grassland. Landfills and roadways are insignificant within the entire Swiss river network, but may locally lead to considerable water pollution. Considering all substance groups, pesticides and some heavy metals are the main polluters. Many pesticides are expected to exceed AA-EQS and in a substantial percentage of the river network. Modeling a large number of substances from many sources and a huge quantity of stream sections is only possible with a simple model. Nevertheless conclusions are robust and may indicate where and for what kind of substance groups additional efforts for water quality improvements should be undertaken.
COMPARISON OF OZONE INDICATORS MONITORED AT CASTNET AND RURALLY - DESIGNATED SLAMS SITES
Many water-bodies within the United States are contaminated by non-point source (NPS) pollution, which is defined as those materials posing a threat to water quality arising from a number of individual sources and diffused through hydrologic 13romses. One such NPS pollutant is fe...
NASA Technical Reports Server (NTRS)
Smith, G. L.; Green, R. N.; Young, G. R.
1974-01-01
The NIMBUS-G environmental monitoring satellite has an instrument (a gas correlation spectrometer) onboard for measuring the mass of a given pollutant within a gas volume. The present paper treats the problem: How can this type measurement be used to estimate the distribution of pollutant levels in a metropolitan area. Estimation methods are used to develop this distribution. The pollution concentration caused by a point source is modeled as a Gaussian plume. The uncertainty in the measurements is used to determine the accuracy of estimating the source strength, the wind velocity, diffusion coefficients and source location.
A review of methods for predicting air pollution dispersion
NASA Technical Reports Server (NTRS)
Mathis, J. J., Jr.; Grose, W. L.
1973-01-01
Air pollution modeling, and problem areas in air pollution dispersion modeling were surveyed. Emission source inventory, meteorological data, and turbulent diffusion are discussed in terms of developing a dispersion model. Existing mathematical models of urban air pollution, and highway and airport models are discussed along with their limitations. Recommendations for improving modeling capabilities are included.
Study of atmospheric diffusion using LANDSAT
NASA Technical Reports Server (NTRS)
Torsani, J. A.; Viswanadham, Y.
1982-01-01
The parameters of diffusion patterns of atmospheric pollutants under different conditions were investigated for use in the Gaussian model for calculation of pollution concentration. Value for the divergence pattern of concentration distribution along the Y axis were determined using LANDSAT images. Multispectral scanner images of a point source plume having known characteristics, wind and temperature data, and cloud cover and solar elevation data provided by LANDSAT, were analyzed using the 1-100 system for image analysis. These measured values are compared with pollution transport as predicted by the Pasquill-Gifford, Juelich, and Hoegstroem atmospheric models.
NASA Astrophysics Data System (ADS)
Drouin, Ariane; Michaud, Aubert; Thériault, Georges; Beaudin, Isabelle; Rodrigue, Jean-François; Denault, Jean-Thomas; Desjardins, Jacques; Côté, Noémi
2013-04-01
In Quebec / Canada, water quality improvement in rural areas greatly depends on the reduction of diffuse pollution. Indeed, point source pollution has been reduced significantly in Canada in recent years by creating circumscribed pits for manure and removing animals from stream. Diffuse pollution differs from point source pollution because it is spread over large areas. In agricultural areas, sediment loss by soil and riverbank erosion along with loss of nutrients (phosphorus, nitrogen, etc.) and pesticides from fields represent the main source of non-point source pollution. The factor mainly responsible for diffuse pollution in agricultural areas is surface runoff occurring in poorly drained areas in fields. The presence of these poorly drained areas is also one of the most limiting factors in crop productivity. Thus, a reconciliation of objectives at the farm (financial concern for farmers) and off-farm concerns (environmental concern) is possible. In short, drainage, runoff, erosion, water quality and crop production are all interconnected issues that need to be tackled together. Two complementary data sources are mainly used in the diagnosis of drainage, surface runoff and erosion : elevation data and multispectral satellite images. In this study of two watersheds located in Québec (Canada), LiDAR elevation data and satellite imagery (QuickBird, Spot and Landsat) were acquired. The studied territories have been partitioned in hydrologic response units (HRUs) according to sub-basins, soils, elevation (topographic index) and land use. These HRUs are afterwards used in a P index software (P-Edit) that calculates the quantities of sediments and phosphorus exported from each HRUs. These exports of sediments and phosphorus are validated with hydrometric and water quality data obtain in two sub-basins and are also compared to soil brightness index derived from multispectral images. This index is sensitive to soil moisture and thus highlights areas where the soil is more humid. A variety of other indices are used to explain the sediments yields. These indices, such as the average percentage of slope, the distance to the stream, the relative position in landscape, the position to the water table, etc. are mainly derived from high precision elevation data. All these data are used to locate critical source areas that generally correspond to a restraint part of the territory but account for the principal amount of sediments exports. Once the critical source areas are identified, best management practices (BMPs) (per example : contaminant source control practices, conservation cropping practices and surface runoff control structures) can be planned. This way, money and energy are used where it really counts. In this presentation, the complete methodology including LiDAR data processing will be explained. The results and the possibility to reproduce the developed method will be discussed.
NASA Astrophysics Data System (ADS)
Voss, Anja; Bärlund, Ilona; Punzet, Manuel; Williams, Richard; Teichert, Ellen; Malve, Olli; Voß, Frank
2010-05-01
Although catchment scale modelling of water and solute transport and transformations is a widely used technique to study pollution pathways and effects of natural changes, policies and mitigation measures there are only a few examples of global water quality modelling. This work will provide a description of the new continental-scale model of water quality WorldQual and the analysis of model simulations under changed climate and anthropogenic conditions with respect to changes in diffuse and point loading as well as surface water quality. BOD is used as an indicator of the level of organic pollution and its oxygen-depleting potential, and for the overall health of aquatic ecosystems. The first application of this new water quality model is to river systems of Europe. The model itself is being developed as part of the EU-funded SCENES Project which has the principal goal of developing new scenarios of the future of freshwater resources in Europe. The aim of the model is to determine chemical fluxes in different pathways combining analysis of water quantity with water quality. Simple equations, consistent with the availability of data on the continental scale, are used to simulate the response of in-stream BOD concentrations to diffuse and anthropogenic point loadings as well as flow dilution. Point sources are divided into manufacturing, domestic and urban loadings, whereas diffuse loadings come from scattered settlements, agricultural input (for instance livestock farming), and also from natural background sources. The model is tested against measured longitudinal gradients and time series data at specific river locations with different loading characteristics like the Thames that is driven by domestic loading and Ebro with relative high share of diffuse loading. With scenario studies the influence of climate and anthropogenic changes on European water resources shall be investigated with the following questions: 1. What percentage of river systems will have degraded water quality due to different driving forces? 2. How will climate change and changes in wastewater discharges affect water quality? For the analysis these scenario aspects are included: 1. climate with changed runoff (affecting diffuse pollution and loading from sealed areas), river discharge (causing dilution or concentration of point source pollution) and water temperature (affecting BOD degradation). 2. Point sources with changed population (affecting domestic pollution), connectivity to treatment plants (influencing domestic and manufacturing pollution as well as input from sealed areas and scattered settlements).
Smolders, Andrew; Rolls, Robert J; Ryder, Darren; Watkinson, Andrew; Mackenzie, Mark
2015-06-01
The provision of safe drinking water is a global issue, and animal production is recognized as a significant potential origin of human infectious pathogenic microorganisms within source water catchments. On-farm management can be used to mitigate livestock-derived microbial pollution in source water catchments to reduce the risk of contamination to potable water supplies. We applied a modified Before-After Control Impact (BACI) design to test if restricting the access of livestock to direct contact with streams prevented longitudinal increases in the concentrations of faecal indicator bacteria and suspended solids. Significant longitudinal increases in pollutant concentrations were detected between upstream and downstream reaches of the control crossing, whereas such increases were not detected at the treatment crossing. Therefore, while the crossing upgrade was effective in preventing cattle-derived point source pollution by between 112 and 158%, diffuse source pollution to water supplies from livestock is not ameliorated by this intervention alone. Our findings indicate that stream crossings that prevent direct contact between livestock and waterways provide a simple method for reducing pollutant loads in source water catchments, which ultimately minimises the likelihood of pathogenic microorganisms passing through source water catchments and the drinking water supply system. The efficacy of the catchment as a primary barrier to pathogenic risks to drinking water supplies would be improved with the integration of management interventions that minimise direct contact between livestock and waterways, combined with the mitigation of diffuse sources of livestock-derived faecal matter from farmland runoff to the aquatic environment. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed
Schilling, K.E.; Helmers, M.
2008-01-01
The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Lebedeff, S. A.; Hameed, S.
1975-01-01
The problem investigated can be solved exactly in a simple manner if the equations are written in terms of a similarity variable. The exact solution is used to explore two questions of interest in the modelling of urban air pollution, taking into account the distribution of surface concentration downwind of an area source and the distribution of concentration with height.
O'Shea, Francis T; Cundy, Andrew B; Spencer, Kate L
2018-03-01
Prior to modern environmental regulation landfills in low-lying coastal environments were frequently constructed without leachate control, relying on natural attenuation within inter-tidal sediments to dilute and disperse contaminants reducing environmental impact. With sea level rise and coastal erosion these sites may now pose a pollution risk, yet have received little investigation. This work examines the extent of metal contamination in saltmarsh sediments surrounding a historic landfill in the UK. Patterns of sediment metal data suggest typical anthropogenic pollution chronologies for saltmarsh sediments in industrialised nations. However, many metals were also enriched at depth in close proximity to the landfill boundary and are indicative of a historical leachate plume. Though this total metal load is low, e.g., c. 1200 and 1650kg Pb and Zn respectively, with >1000 historic landfills on flood risk or eroding coastlines in the UK this could represent a significant, yet under-investigated, source of diffuse pollution. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Diffuse pollution of soil and water: Long term trends at large scales?
NASA Astrophysics Data System (ADS)
Grathwohl, P.
2012-04-01
Industrialization and urbanization, which consequently increased pressure on the environment to cause degradation of soil and water quality over more than a century, is still ongoing. The number of potential environmental contaminants detected in surface and groundwater is continuously increasing; from classical industrial and agricultural chemicals, to flame retardants, pharmaceuticals, and personal care products. While point sources of pollution can be managed in principle, diffuse pollution is only reversible at very long time scales if at all. Compounds which were phased out many decades ago such as PCBs or DDT are still abundant in soils, sediments and biota. How diffuse pollution is processed at large scales in space (e.g. catchments) and time (centuries) is unknown. The relevance to the field of processes well investigated at the laboratory scale (e.g. sorption/desorption and (bio)degradation kinetics) is not clear. Transport of compounds is often coupled to the water cycle and in order to assess trends in diffuse pollution, detailed knowledge about the hydrology and the solute fluxes at the catchment scale is required (e.g. input/output fluxes, transformation rates at the field scale). This is also a prerequisite in assessing management options for reversal of adverse trends.
SCIMAP: Modelling Diffuse Pollution in Large River Basins
NASA Astrophysics Data System (ADS)
Milledge, D.; Heathwaite, L.; Lane, S. N.; Reaney, S. M.
2009-12-01
Polluted rivers are a problem for the plants and animals that require clean water to survive. Watershed scale processes can influence instream aquatic ecosystems by delivering fine sediment, solutes and organic matter from diffuse sources. To improve our rivers we need to identify the pollution sources. Models can help us to do this but these rarely address the extent to which risky land uses are hydrologically-connected, and hence able to deliver, to the drainage network. Those that do tend to apply a full hydrological scheme, which is unfeasible for large watersheds. Here we develop a risk-based modelling framework, SCIMAP, for diffuse pollution from agriculture (Nitrate, Phosphate and Fine Sediment). In each case the basis of the analysis is the joint consideration of the probability of a unit of land (25 m2 cell) producing a particular environmental risk and then of that risk reaching the river. The components share a common treatment of hydrological connectivity but differ in their treatment of each pollution type. We test and apply SCIMAP using spatially-distributed instream water quality data for some of the UK’s largest catchments to infer the processes and the associated process parameters that matter in defining their concentrations. We use these to identify a series of risky field locations, where this land use is readily connected to the river system by overland flow.
NASA Astrophysics Data System (ADS)
Mockler, Eva; Reaney, Simeon; Mellander, Per-Erik; Wade, Andrew; Collins, Adrian; Arheimer, Berit; Bruen, Michael
2017-04-01
The agricultural sector is the most common suspected source of nutrient pollution in Irish rivers. However, it is also often the most difficult source to characterise due to its predominantly diffuse nature. Particulate phosphorus in surface water and dissolved phosphorus in groundwater are of particular concern in Irish water bodies. Hence the further development of models and indices to assess diffuse sources of contaminants are required for use by the Irish Environmental Protection Agency (EPA) to provide support for river basin planning. Understanding connectivity in the landscape is a vital component of characterising the source-pathway-receptor relationships for water-borne contaminants, and hence is a priority in this research. The DIFFUSE Project will focus on connectivity modelling and incorporation of connectivity into sediment, nutrient and pesticide risk mapping. The Irish approach to understanding and managing natural water bodies has developed substantially in recent years assisted by outputs from multiple research projects, including modelling and analysis tools developed during the Pathways and CatchmentTools projects. These include the Pollution Impact Potential (PIP) maps, which are an example of research output that is used by the EPA to support catchment management. The PIP maps integrate an understanding of the pollution pressures and mobilisation pathways and, using the source-pathways-receptor model, provide a scientific basis for evaluation of mitigation measures. These maps indicate the potential risk posed by nitrate and phosphate from diffuse agricultural sources to surface and groundwater receptors and delineate critical source areas (CSAs) as a means of facilitating the targeting of mitigation measures. Building on this previous research, the DIFFUSE Project will develop revised and new catchment managements tools focused on connectivity, sediment, phosphorus and pesticides. The DIFFUSE project will strive to identify the state-of-the-art methods and models that are most applicable to Irish conditions and management challenges. All styles of modelling considered useful for water resources management are relevant to this project and a balance of technical sophistication, data availability and operational practicalities is the ultimate goal. Achievement of this objective will be measured by comparing the performance of the new models developed in the project with models used in other countries. The models and tools developed in the course of the project will be evaluated by comparison with Irish catchment data and with other state-of-the-art models in a model-inter-comparison workshop which will be open to other models and the wider research community.
The Minnesota River (Minnesota, USA) receives large non-point source pollutant loads. Complex interactions between agricultural, state agency, environmental groups, and issues of scale make watershed management difficult. Subdividing the basin's 12 major water...
Research on sudden environmental pollution public service platform construction based on WebGIS
NASA Astrophysics Data System (ADS)
Bi, T. P.; Gao, D. Y.; Zhong, X. Y.
2016-08-01
In order to actualize the social sharing and service of the emergency-response information for sudden pollution accidents, the public can share the risk source information service, dangerous goods control technology service and so on, The SQL Server and ArcSDE software are used to establish a spatial database to restore all kinds of information including risk sources, hazardous chemicals and handling methods in case of accidents. Combined with Chinese atmospheric environmental assessment standards, the SCREEN3 atmospheric dispersion model and one-dimensional liquid diffusion model are established to realize the query of related information and the display of the diffusion effect under B/S structure. Based on the WebGIS technology, C#.Net language is used to develop the sudden environmental pollution public service platform. As a result, the public service platform can make risk assessments and provide the best emergency processing services.
WET WEATHER FLOW (WWF) MANAGEMENT AND CONTROL
Research emphasizes structural and nonstructural approaches that reduce the impacts of WWF-related stressors on receiving waters. Urban WWF pollution emanates from both point sources and diffuse sources including CSOs, SSOs, and stormwater from sewered and unsewered systems. EPA’...
ERIC Educational Resources Information Center
Larsen, Ralph I.
1973-01-01
Makes recommendations for a single air quality data system (using average time) for interrelating air pollution effects, air quality standards, air quality monitoring, diffusion calculations, source-reduction calculations, and emission standards. (JR)
Denitrifying bioreactor clogging potential during wastewater treatment
USDA-ARS?s Scientific Manuscript database
Chemoheterotrophic denitrification technologies using woodchips as a solid carbon source (i.e., woodchip bioreactors) have been widely trialed for treatment of diffuse-source agricultural nitrogen pollution. There is growing interest in the use of this simple, relatively low-cost biological wastewat...
Alberti, Luca; Colombo, Loris; Formentin, Giovanni
2018-04-15
The Lombardy Region in Italy is one of the most urbanized and industrialized areas in Europe. The presence of countless sources of groundwater pollution is therefore a matter of environmental concern. The sources of groundwater contamination can be classified into two different categories: 1) Point Sources (PS), which correspond to areas releasing plumes of high concentrations (i.e. hot-spots) and 2) Multiple-Point Sources (MPS) consisting in a series of unidentifiable small sources clustered within large areas, generating an anthropogenic diffuse contamination. The latter category frequently predominates in European Functional Urban Areas (FUA) and cannot be managed through standard remediation techniques, mainly because detecting the many different source areas releasing small contaminant mass in groundwater is unfeasible. A specific legislative action has been recently enacted at Regional level (DGR IX/3510-2012), in order to identify areas prone to anthropogenic diffuse pollution and their level of contamination. With a view to defining a management plan, it is necessary to find where MPS are most likely positioned. This paper describes a methodology devised to identify the areas with the highest likelihood to host potential MPS. A groundwater flow model was implemented for a pilot area located in the Milan FUA and through the PEST code, a Null-Space Monte Carlo method was applied in order to generate a suite of several hundred hydraulic conductivity field realizations, each maintaining the model in a calibrated state and each consistent with the modelers' expert-knowledge. Thereafter, the MODPATH code was applied to generate back-traced advective flowpaths for each of the models built using the conductivity field realizations. Maps were then created displaying the number of backtracked particles that crossed each model cell in each stochastic calibrated model. The result is considered to be representative of the FUAs areas with the highest likelihood to host MPS responsible for diffuse contamination. Copyright © 2017 Elsevier B.V. All rights reserved.
C. E., Jr. Murphy; T. R. Sinclair; K. R. Knoerr
1977-01-01
The computer model presented in this paper is designed to estimate the uptake of air pollutants by forests. The model utilizes submodels to describe atmospheric diffusion immediately above and within the canopy, and into the sink areas within or on the trees. The program implementing the model is general and can be used with only minor changes for any gaseous pollutant...
UTILIZATION OF LANDSCAPE INDICATORS TO MODEL WATER QUALITY
Many water-bodies within the United States are contaminated by, non-point source (NFS) pollution, which is defined as those materials posing a threat to water quality arising from a number of individual sources and diffused through hydrologic processes. One such NPS pollu...
Li, Jia; Zhang, Haibo; Chen, Yongshan; Luo, Yongming; Zhang, Hua
2016-07-01
To quantify the extent of antibiotic contamination and to identity the dominant pollutant sources in the Tiaoxi River Watershed, surface water samples were collected at eight locations and analyzed for four tetracyclines and three sulfonamides using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The observed maximum concentrations of tetracycline (623 ng L(-1)), oxytetracycline (19,810 ng L(-1)), and sulfamethoxazole (112 ng L(-1)) exceeded their corresponding Predicted No Effect Concentration (PNEC) values. In particular, high concentrations of antibiotics were observed in wet summer with heavy rainfall. The maximum concentrations of antibiotics appeared in the vicinity of intensive aquaculture areas. High-resolution land use data were used for identifying diffuse source of antibiotic pollution in the watershed. Significant correlations between tetracycline and developed (r = 0.93), tetracycline and barren (r = 0.87), oxytetracycline and barren (r = 0.82), and sulfadiazine and agricultural facilities (r = 0.71) were observed. In addition, the density of aquaculture significantly correlated with doxycycline (r = 0.74) and oxytetracycline (r = 0.76), while the density of livestock significantly correlated with sulfadiazine (r = 0.71). Principle Component Analysis (PCA) indicated that doxycycline, tetracycline, oxytetracycline, and sulfamethoxazole were from aquaculture and domestic sources, whereas sulfadiazine and sulfamethazine were from livestock wastewater. Flood or drainage from aquaculture ponds was identified as a major source of antibiotics in the Tiaoxi watershed. A hot-spot map was created based on results of land use analysis and multi-variable statistics, which provided an effective management tool of sources identification in watersheds with multiple diffuse sources of antibiotic pollution.
UTILIZATION OF LANDSCAPE INDICATORS TO MODEL WATERSHED IMPAIRMENT
Many water-bodies within the United States are contaminated by non-point source (NPS) pollution, which is defined as those materials posing a threat to water quality arising from a number of individual sources and diffused through hydrologic 13romses. One such NPS
pol...
Boundary Layer Model for Air Pollutant Concentrations Due to Highway Traffic
ERIC Educational Resources Information Center
Ragland, Kenneth W.; Peirce, J. Jeffrey
1975-01-01
A numerical solution of the three-dimensional steady-state diffusion equation for a finite width line source is presented. The wind speed and eddy diffusivity as a function of height above the roadway are obtained. Normalized ground level and elevated concentrations near a highway are obtained for winds perpendicular, parallel, and at 45 degrees.…
Estimation of Phosphorus Emissions in the Upper Iguazu Basin (brazil) Using GIS and the More Model
NASA Astrophysics Data System (ADS)
Acosta Porras, E. A.; Kishi, R. T.; Fuchs, S.; Hilgert, S.
2016-06-01
Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions) model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations) and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for about 56% of the emissions. Second significant shares of emissions come from direct runoff or groundwater, being responsible for 32% of the total emissions. Finally, agricultural erosion and industry pathways represent 12% of emissions. This study shows that MoRE is capable of producing valid emission calculation on a relatively reduced input data basis.
Nationwide assessment of nonpoint source threats to water quality
Thomas C. Brown; Pamela Froemke
2012-01-01
Water quality is a continuing national concern, in part because the containment of pollution from nonpoint (diffuse) sources remains a challenge. We examine the spatial distribution of nonpoint-source threats to water quality. On the basis of comprehensive data sets for a series of watershed stressors, the relative risk of water-quality impairment was estimated for the...
Air Quality Impact of Diffuse and Inefficient Combustion Emissions in Africa (DICE-Africa).
Marais, Eloise A; Wiedinmyer, Christine
2016-10-04
Anthropogenic pollution in Africa is dominated by diffuse and inefficient combustion sources, as electricity access is low and motorcycles and outdated cars proliferate. These sources are missing, out-of-date, or misrepresented in state-of-the-science emission inventories. We address these deficiencies with a detailed inventory of Diffuse and Inefficient Combustion Emissions in Africa (DICE-Africa) for 2006 and 2013. Fuelwood for energy is the largest emission source in DICE-Africa, but grows from 2006 to 2013 at a slower rate than charcoal production and use, and gasoline and diesel for motorcycles, cars, and generators. Only kerosene use and gas flaring decline. Increase in emissions from 2006 to 2013 in this work is consistent with trends in satellite observations of formaldehyde and NO 2 , but much slower than the explosive growth projected with a fuel consumption model. Seasonal biomass burning is considered a large pollution source in Africa, but we estimate comparable emissions of black carbon and higher emissions of nonmethane volatile organic compounds from DICE-Africa. Nitrogen oxide (NO x ≡ NO + NO 2 ) emissions are much lower than from biomass burning. We use GEOS-Chem to estimate that the largest contribution of DICE-Africa to annual mean surface fine particulate matter (PM 2.5 ) is >5 μg m -3 in populous Nigeria.
Quantitative evaluation of water quality in the coastal zone by remote sensing
NASA Technical Reports Server (NTRS)
James, W. P.
1971-01-01
Remote sensing as a tool in a waste management program is discussed. By monitoring both the pollution sources and the environmental quality, the interaction between the components of the exturaine system was observed. The need for in situ sampling is reduced with the development of improved calibrated, multichannel sensors. Remote sensing is used for: (1) pollution source determination, (2) mapping the influence zone of the waste source on water quality parameters, and (3) estimating the magnitude of the water quality parameters. Diffusion coefficients and circulation patterns can also be determined by remote sensing, along with subtle changes in vegetative patterns and density.
Xue, Yi-feng; Zhou, Zhen; Nie, Teng; Pan, Tao; Qi, Jun; Nie, Lei; Wang, Zhan-shan; Li, Yun-ting; Li, Xue-feng; Tian, He-zhong
2016-05-15
Severe haze episodes shrouded Beijing and its surrounding regions again during December, 2015, causing major environmental and health problems. Beijing authorities had launched two red alerts for atmospheric heavy pollution in this period, adopted a series of emergency control measures to reduce the emissions from major pollution sources. To better understand the pollution process and emissions variation during these extreme pollution events, we performed a model-assisted analysis of the hourly observation data of PM₂.₅, and meteorological parameters combined with the emissions variation of pollution sources. The synthetic analysis indicated that: (1) Compared with the same period of last year, the emissions of atmospheric pollution sources decreased in December 2015. However, the emission levels of primary pollutants were still rather high, which were the main intrinsic causes for haze episodes, and the unfavorable diffusion conditions represented the important external factor. High source emissions and meteorological factors together led to this heavy air pollution process. (2) Emergency control measures taken by the red alert for heavy air pollution could decrease the pollutants emission by about 36% and the PM₂.₅ concentrations by 11% to 21%. Though the implementation of red alert could not reverse the evolution trend of heavier pollution, it indeed played an active role in mitigation of PM₂.₅ pollution aggravating. (3) Under the heavy pollution weather conditions, air pollutants continued to accumulate in the atmosphere, and the maximum effect by taking emergency measures occurred 48-72 hours after starting the implementation; therefore, the best time for executing emergency measures should be 36-48 hours before the rapid rise of PM₂.₅ concentration, which requires a more powerful demand on the accuracy of air quality forecast.
Wither, A; Greaves, J; Dunhill, I; Wyer, M; Stapleton, C; Kay, D; Humphrey, N; Watkins, J; Francis, C; McDonald, A; Crowther, J
2005-01-01
Achieving compliance with the mandatory standards of the 1976 Bathing Water Directive (76/160/EEC) is required at all U.K. identified bathing waters. In recent years, the Fylde coast has been an area of significant investments in 'point source' control, which have not proven, in isolation, to satisfactorily achieve compliance with the mandatory, let alone the guide, levels of water quality in the Directive. The potential impact of riverine sources of pollution was first confirmed after a study in 1997. The completion of sewerage system enhancements offered the potential for the study of faecal indicator delivery from upstream sources comprising both point sources and diffuse agricultural sources. A research project to define these elements commenced in 2001. Initially, a desk study reported here, estimated the principal infrastructure contributions within the Ribble catchment. A second phase of this investigation has involved acquisition of empirical water quality and hydrological data from the catchment during the 2002 bathing season. These data have been used further to calibrate the 'budgets' and 'delivery' modelling and these data are still being analysed. This paper reports the initial desk study approach to faecal indicator budget estimation using available data from the sewerage infrastructure and catchment sources of faecal indicators.
Approach to identifying pollutant source and matching flow field
NASA Astrophysics Data System (ADS)
Liping, Pang; Yu, Zhang; Hongquan, Qu; Tao, Hu; Wei, Wang
2013-07-01
Accidental pollution events often threaten people's health and lives, and it is necessary to identify a pollutant source rapidly so that prompt actions can be taken to prevent the spread of pollution. But this identification process is one of the difficulties in the inverse problem areas. This paper carries out some studies on this issue. An approach using single sensor information with noise was developed to identify a sudden continuous emission trace pollutant source in a steady velocity field. This approach first compares the characteristic distance of the measured concentration sequence to the multiple hypothetical measured concentration sequences at the sensor position, which are obtained based on a source-three-parameter multiple hypotheses. Then we realize the source identification by globally searching the optimal values with the objective function of the maximum location probability. Considering the large amount of computation load resulting from this global searching, a local fine-mesh source search method based on priori coarse-mesh location probabilities is further used to improve the efficiency of identification. Studies have shown that the flow field has a very important influence on the source identification. Therefore, we also discuss the impact of non-matching flow fields with estimation deviation on identification. Based on this analysis, a method for matching accurate flow field is presented to improve the accuracy of identification. In order to verify the practical application of the above method, an experimental system simulating a sudden pollution process in a steady flow field was set up and some experiments were conducted when the diffusion coefficient was known. The studies showed that the three parameters (position, emission strength and initial emission time) of the pollutant source in the experiment can be estimated by using the method for matching flow field and source identification.
How to Detect the Location and Time of a Covert Chemical Attack: A Bayesian Approach
2009-12-01
Inverse Problems, Design and Optimization Symposium 2004. Rio de Janeiro , Brazil. Chan, R., and Yee, E. (1997). A simple model for the probability...sensor interpretation applications and has been successfully applied, for example, to estimate the source strength of pollutant releases in multi...coagulation, and second-order pollutant diffusion in sorption- desorption, are not linear. Furthermore, wide uncertainty bounds exist for several of
The impact of land use on microbial surface water pollution.
Schreiber, Christiane; Rechenburg, Andrea; Rind, Esther; Kistemann, Thomas
2015-03-01
Our knowledge relating to water contamination from point and diffuse sources has increased in recent years and there have been many studies undertaken focusing on effluent from sewage plants or combined sewer overflows. However, there is still only a limited amount of microbial data on non-point sources leading to diffuse pollution of surface waters. In this study, the concentrations of several indicator micro-organisms and pathogens in the upper reaches of a river system were examined over a period of 16 months. In addition to bacteria, diffuse pollution caused by Giardia lamblia and Cryptosporidium spp. was analysed. A single land use type predestined to cause high concentrations of all microbial parameters could not be identified. The influence of different land use types varies between microbial species. The microbial concentration in river water cannot be explained by stable non-point effluent concentrations from different land use types. There is variation in the ranking of the potential of different land use types resulting in surface water contamination with regard to minimum, median and maximum effects. These differences between median and maximum impact indicate that small-scale events like spreading manure substantially influence the general contamination potential of a land use type and may cause increasing micro-organism concentrations in the river water by mobilisation during the next rainfall event. Copyright © 2014 Elsevier GmbH. All rights reserved.
Importance of diffuse pollution control in the Patzcuaro Lake Basin in Mexico.
Carro, Marco Mijangos; Dávila, Jorge Izurieta; Balandra, Antonieta Gómez; López, Rubén Hernández; Delgadillo, Rubén Huerto; Chávez, Javier Sánchez; Inclán, Luís Bravo
2008-01-01
In the catchment area of the Lake Patzcuaro in Central Mexico (933 km2) the apportionments of erosion, sediment, nutrients and pathogen coming from thirteen micro basins were estimated with the purpose of identifying critical areas in which best management practices need to be implemented in order to reduce their contribution to the lake pollution and eutrophication. The ArcView Generalized Watershed Loading Functions model (AV-GWLF) was applied to estimate the loads and sources of nutrients. The main results show that the total annual contribution of nitrogen from point sources were 491 tons and from diffuse pollution 2,065 tons, whereas phosphorus loads where 116 and 236 tons, respectively during a thirty year simulation period. Micro basins with predominant agricultural and animal farm land use (56% of the total area) accounts for a high percentage of nitrogen load 33% and phosphorus 52%. On the other hand, Patzcuaro and Quiroga micro basins which comprise approximately 10% of the total catchment area and are the most populated and visited towns by tourist 686,000 people every year, both contributes with 10.1% of the total nitrogen load and 3.2% of phosphorus. In terms of point sources of nitrogen and phosphorus the last towns contribute with 23.5% and 26.6% respectively. Under this situation the adoption of best management practices are an imperative task since the sedimentation and pollution in the lake has increased dramatically in the last twenty years. Copyright (c) IWA Publishing 2008.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azad, A.K.; Kitada, T.
1996-12-31
Dhaka is the capital and the biggest city of Bangladesh, and is expanding very rapidly. Emissions from heavy traffic and many small industries and commercial complexes, newly developed in and around the city, are polluting the air of Dhaka city. The air pollution is severe especially in winter due to adverse meteorological conditions such as low wind speed and dry, stably-stratified air, which restricts the mixing height to low levels and prevent dispersion of pollutants. But so far no study of air pollution of Dhaka city has been done. We have first measured SO{sub 2} and NO{sub 2} concentrations inmore » Dhaka city in a large scale and derived their spatial distributions over Dhaka. Molecular diffusion tubes, which do not require power sources and are produced at low cost, have been used to measure the concentration distributions of SO{sub 2} and NO{sub 2} at 64 sites in Dhaka city and its suburbs during the period of December-January of 1995-96. The diffusion tube samplers were calibrated using 6 automated air pollution monitoring stations in Aichi-prefecture, Japan. The calibration curve and the distribution of the concentration data acquired by automatic measurement instrument at each location showed that the error range of measurements with the molecular diffusion tube samplers was 2-27%. The samples were analyzed using ion-chromatography and spectrophotometer to determine the concentrations of SO{sub 2} and NO{sub 2} respectively. The contamination of unexposed tubes under field conditions was determined and the value of the blank test was subtracted from the measurements of the diffusion tube samplers. The effects of wind turbulence and temperature were reduced using polyflon filters.« less
Using natural archives to track sources and long-term trends of pollution: an introduction
Jules Blais,; Rosen, Michael R.; John Smol,
2015-01-01
This book explores the myriad ways that environmental archives can be used to study the distribution and long-term trajectories of contaminants. The volume first focuses on reviews that examine the integrity of the historic record, including factors related to hydrology, post-depositional diffusion, and mixing processes. This is followed by a series of chapters dealing with the diverse archives available for long-term studies of environmental pollution.
NASA Astrophysics Data System (ADS)
Thomas, Ian; Jordan, Phil; Mellander, Per-Erik; Fenton, Owen; Shine, Oliver; hUallacháin, Daire Ó.; Creamer, Rachel; McDonald, Noeleen; Dunlop, Paul; Murphy, Paul
2016-04-01
Identifying critical source areas (CSAs) of diffuse pollution in agricultural catchments requires the accurate identification of hydrologically sensitive areas (HSAs) at highest propensity for generating surface runoff and transporting pollutants such as phosphorus (P). A new GIS-based HSA Index is presented that identifies HSAs at the sub-field scale. It uses a soil topographic index (STI) and accounts for the hydrological disconnection of overland flow via topographic impediment from flow sinks such as hedgerows and depressions. High resolution (0.25-2 m) LiDAR Digital Elevation Models (DEMs) are utilised to capture these microtopographic controls on flow pathways and hydrological connectivity. The HSA Index was applied to four agricultural catchments (~7.5-12 km2) with contrasting topography and soil types. Catchment HSA sizes were estimated using high resolution rainfall-quickflow measurements during saturated winter storm events in 2009-2014, and mapped using the HSA Index. HSA sizes ranged from 1.6-3.4% of the catchment area during median storm events and 2.9-8.5% during upper quartile events depending on whether well or poorly drained soils dominated, which validated HSA Index value distributions. Total flow sink volume capacities ranged from 8,298-59,584 m3 and caused 8.5-24.2% of overland-flow-generating-areas and 16.8-33.4% of catchment areas to become hydrologically disconnected from the open drainage channel network. HSA maps identified 'delivery points' along surface runoff pathways where transported pollutants such as P are delivered to the open drainage network. Using these as proposed locations for targeting mitigation measures such as riparian buffer strips (RBS) reduced costs compared to blanket implementation within an example agri-environment scheme by 66% and 91% over 1 and 5 years respectively, which included LiDAR DEM acquisition costs. Considering that HSAs are often the dominant P CSA factor in agricultural catchments and can override source pressures, targeting measures at HSAs is potentially a more sustainable, cost-effective and policy-applicable strategy for mitigating diffuse pollution.
Simulating the evolution of non-point source pollutants in a shallow water environment.
Yan, Min; Kahawita, Rene
2007-03-01
Non-point source pollution originating from surface applied chemicals in either liquid or solid form as part of agricultural activities, appears in the surface runoff caused by rainfall. The infiltration and transport of these pollutants has a significant impact on subsurface and riverine water quality. The present paper describes the development of a unified 2-D mathematical model incorporating individual models for infiltration, adsorption, solubility rate, advection and diffusion, which significantly improve the current practice on mathematical modeling of pollutant evolution in shallow water. The governing equations have been solved numerically using cubic spline integration. Experiments were conducted at the Hydrodynamics Laboratory of the Ecole Polytechnique de Montreal to validate the mathematical model. Good correspondence between the computed results and experimental data has been obtained. The model may be used to predict the ultimate fate of surface applied chemicals by evaluating the proportions that are dissolved, infiltrated into the subsurface or are washed off.
Soils as sinks or sources for diffuse pollution of the water cycle
NASA Astrophysics Data System (ADS)
Grathwohl, Peter
2010-05-01
Numerous chemical compounds have been released into the environment by human activities and can nowadays be found everywhere, i.e. in the compartments water, soil, and air, at the poles and in high mountains. Examples for a global distribution of toxic compounds are the persistent organic pollutants (PCB, dioxins, PAH, fluorinated surfactants and flame retardants, etc.: "the Stockholm dirty dozen") but also mercury and other metals. Many of these compounds reached a global distribution via the atmo¬sphere; others have been and are still directly applied to top soils at the large scale by agriculture or are released into groundwater at landfill sites or by discharge of treated or untreated waste waters. Sooner or later such compounds end up in the water cycle - often via an intermediate storage in soils. Pollutants in soils are leached by seepage waters, transferred to ground¬water, and transported to rivers via groundwater flow. Adsorbed compounds may be transported from soils into surface waters by erosion processes and will end up in the sediments. Diffuse pollution of the subsurface environment not only reflects the history of the economic development of the modern society but it is still ongoing - e.g. the number of organic pollutants released into the environment is increasing even though the con¬centrations may decrease compared to the past. Evidence shows that many compounds are persistent in the subsurface environment at large time scales (up to centuries). Thus polluted soils already are or may become a future source for pollution of adjacent compartments such as the atmosphere and groundwater. A profound understanding on how diffuse pollutants are stored and processed in the subsurface environment is crucial to assess their long term fate and transport at large scales. Thus integrated studies e.g. at the catchment scale and models are needed which couple not only the relevant compartments (soil - atmosphere - groundwater/surface waters) but also flow and reactive transport. Field observations must allow long-term monitoring (e.g. in hydrological observatories, TERENO etc.), new cross-compartment monitoring strategies need to be applied, and massive parallel numerical codes for prediction of reactive transport of potential water pollutants at catchment scale have to be developed. This is also a prerequisite to assess the impact of climate change as well as land use change on future surface and groundwater quality.
Lee, Dae-Young; Lee, Hung; Trevors, Jack T; Weir, Susan C; Thomas, Janis L; Habash, Marc
2014-04-15
Sources of fecal water pollution were assessed in the Grand River and two of its tributaries (Ontario, Canada) using total and host-specific (human and bovine) Bacteroidales genetic markers in conjunction with reference information, such as land use and weather. In-stream levels of the markers and culturable Escherichia coli were also monitored during multiple rain events to gain information on fecal loadings to catchment from diffuse sources. Elevated human-specific marker levels were accurately identified in river water impacted by a municipal wastewater treatment plant (WWTP) effluent and at a downstream site in the Grand River. In contrast, the bovine-specific marker showed high levels of cattle fecal pollution in two tributaries, both of which are characterized as intensely farmed areas. The bovine-specific Bacteroidales marker increased with rainfall in the agricultural tributaries, indicating enhanced loading of cattle-derived fecal pollutants to river from non-point sources following rain events. However, rain-triggered fecal loading was not substantiated in urban settings, indicating continuous inputs of human-originated fecal pollutants from point sources, such as WWTP effluent. This study demonstrated that the Bacteroidales source tracking assays, in combination with land use information and hydrological data, may provide additional insight into the spatial and temporal distribution of source-specific fecal contamination in streams impacted by varying land uses. Using the approach described in this study may help to characterize impacted water sources and to design targeted land use management plans in other watersheds in the future. Copyright © 2014 Elsevier Ltd. All rights reserved.
Zhang, Lixun; Zhao, Bo; Xu, Gang; Guan, Yuntao
2018-09-01
Globally, fluvial heavy metal (HM) pollution has recently become an increasingly severe problem. However, few studies have investigated the variational characteristics of fluvial HMs after rain over long periods (≥1 year). The Dakan River in Xili Reservoir watershed (China) was selected as a case study to investigate pollution levels, influencing factors, and sources of HMs under different rainfall conditions during 2015 and 2016. Fluvial HMs showed evident spatiotemporal variations attributable to the coupled effects of pollution generation and rainfall diffusion. Fluvial HM concentrations were significantly associated with rainfall characteristics (e.g., rainfall intensity, rainfall amount, and antecedent dry period) and river flow, which influenced the generation and the transmission of fluvial HMs in various ways. Moreover, this interrelationship depended considerably on the HM type and particle size distribution. Mn, Pb, Cr, and Ni were major contributors to high values of the comprehensive pollution index; therefore, they should be afforded special attention. Additionally, quantitative source apportionment of fluvial HMs was conducted by combining principal component analysis with multiple linear regression and chemical mass balance models to obtain comprehensive source profiles. Finally, an environment-friendly control strategy coupling "source elimination" and "transport barriers" was proposed for aquatic environment protection. Copyright © 2018 Elsevier B.V. All rights reserved.
Making Our Nonpoint Source Pollution Education Programs Effective.
ERIC Educational Resources Information Center
Shepard, Robin
1999-01-01
The rate of adoption of nutrient management by farmers in Wisconsin watersheds was compared for a program using diffuse communication strategies and one using one-to-one information transfer. Information transfer increased adoption of specific practices and decreased application of excessive nitrogen and phosphorus. (SK)
Decline in Chinese lake phosphorus concentration accompanied by shift in sources since 2006
NASA Astrophysics Data System (ADS)
Tong, Yindong; Zhang, Wei; Wang, Xuejun; Couture, Raoul-Marie; Larssen, Thorjørn; Zhao, Yue; Li, Jing; Liang, Huijiao; Liu, Xueyan; Bu, Xiaoge; He, Wei; Zhang, Qianggong; Lin, Yan
2017-07-01
Domestic wastewater and agricultural activities are important sources of nutrient pollutants such as phosphorus and nitrogen. Upon reaching freshwater, these nutrients can lead to extensive growth of harmful algae, which results in eutrophication. Many Chinese lakes are subject to such eutrophication, especially in highly polluted areas, and as such, understanding nutrient fluxes to these lakes offers insights into the varying processes governing pollutant fluxes as well as lake water quality. Here we analyse water quality data, recorded between 2006 and 2014 in 862 freshwater lakes in four geographical regions of China, to assess the input of phosphorus from human activity. We find that improvements in sanitation of both rural and urban domestic wastewater have resulted in large-scale declines in lake phosphorus concentrations in the most populated parts of China. In more sparsely populated regions, diffuse sources such as aquaculture and livestock farming offset this decline. Anthropogenic deforestation and soil erosion may also offset decreases in point sources of pollution. In the light of these regional differences, we suggest that a spatially flexible set of policies for water quality control would be beneficial for the future health of Chinese lakes.
Hitherto, stormwater runoff from suburban land-uses has been largely unregulated and designated as a non-point source. Phase II of the Clean Water Act will require permits under the National Pollutant Discharge Elimination System for stormwater discharges from municipal separate ...
Hitherto, stormwater runoff from suburban land-uses has been largely unregulated and designated as a non-point source. Phase II of the Clean Water Act now requires permits under the National Pollutant Discharge Elimination System for stormwater discharges from municipal separate...
Turunen, Jarno; Muotka, Timo; Vuori, Kari-Matti; Karjalainen, Satu Maaria; Rääpysjärvi, Jaana; Sutela, Tapio; Aroviita, Jukka
2016-02-15
Non-point diffuse pollution from land use and alteration of hydromorphology are among the most detrimental stressors to stream ecosystems. We explored the independent and interactive effects of morphological channel alteration (channelization for water transport of timber) and diffuse pollution on species richness and community structure of four organism groups in boreal streams: diatoms, macrophytes, macroinvertebrates, and fish. Furthermore, the effect of these stressors on stream condition was evaluated by Ecological Quality Ratios (EQR) from the national Water Framework Directive (WFD) assessment system. We grouped 91 study sites into four groups that were impacted by either diffuse pollution or hydromorphological alteration, by both stressors, or by neither one. Macroinvertebrate richness was reduced by diffuse pollution, whereas other biological groups were unaltered. Hydromorphological modification had no effect on taxon richness of any of the assemblages. Community structure of all groups was significantly affected by diffuse pollution but not by hydromorphology. Similarly, EQRs indicated negative response by diatoms, macroinvertebrates and fish to diffuse pollution, but not to hydromorphological alteration. Agricultural diffuse pollution thus affected species identities and abundances rather than taxonomic richness. Our results suggest that channelization of boreal streams for timber transport has not altered hydromorphological conditions sufficiently to have a strong impact on stream biota, whereas even moderate nutrient enrichment may be ecologically harmful. Controlling diffuse pollution and associated land use stressors should be prioritized over restoration of in-stream habitat structure to improve the ecological condition of boreal streams. Copyright © 2015 Elsevier B.V. All rights reserved.
Neal, Colin; Jarvie, Helen P; Withers, Paul J A; Whitton, Brian A; Neal, Margaret
2010-03-01
The relationship between soluble and particulate phosphorus was examined for 9 major UK rivers including 26 major tributaries and 68 monitoring points, covering wide-ranging rural and agricultural/urban impacted systems with catchment areas varying from 1 to 6000km(2) scales. Phosphorus concentrations in Soluble Reactive (SRP), Total Dissolved (TDP), Total (TP), Dissolved Hydrolysable (DHP) and Particulate (PP) forms correlated with effluent markers (sodium and boron) and SRP was generally dominant signifying the importance of sewage sources. Low flows were particularly enriched in SRP, TDP and TP for average SRP>100microg/l indicating low effluent dilution. At particularly low average concentrations, SRP increased with flow but effluent sources were still implicated as the effluent markers (boron in particular) increased likewise. For rural areas, DHP had proportionately high concentrations and SRP+DHP concentrations could exceed environmental thresholds currently set for SRP. Given DHP has a high bioavailability the environmental implications need further consideration. PP concentrations were generally highest at high flows but PP in the suspended solids was generally at its lowest and in general PP correlated with particulate organic carbon and more so than the suspended sediment in total. Separation of pollutant inputs solely between effluent and diffuse (agriculture) components is misleading, as part of the "diffuse" term comprises effluents flushed from the catchments during high flow. Effluent sources of phosphorus supplied directly or indirectly to the river coupled with within-river interactions between water/sediment/biota largely determine pollutant levels. The study flags the fundamental need of placing direct and indirect effluent sources and contaminated storage with interchange to/from the river at the focus for remediation strategies for UK rivers in relation to eutrophication and the WFD.
Ozone and haze pollution effects on the contemporary land carbon cycle
NASA Astrophysics Data System (ADS)
Unger, N.
2016-12-01
Atmospheric pollutants have both beneficial and detrimental effects on carbon uptake by land ecosystems. Surface ozone damages leaf photosynthesis by oxidizing plant cells, while aerosols promote carbon uptake by increasing diffuse radiation and exert additional influences through concomitant perturbations to meteorology and hydrology. Here, I present new results from three assessment studies that employ Earth system modeling and multiple measurement datasets. First, we quantify the separate and combined effects of anthropogenic ozone and aerosol pollution on the global land carbon uptake. Second, we evaluate benefits to land ecosystem health from selective emission reductions in specific pollution sources and sectors. Finally, I show that the long-term climatic effects of mid-latitude air pollution boosts plant productivity in the Amazon by 10% on the annual average today.
Recent Progress in the Remote Detection of Vapours and Gaseous Pollutants.
ERIC Educational Resources Information Center
Moffat, A. J.; And Others
Work has been continuing on the correlation spectrometry techniques described at previous remote sensing symposiums. Advances in the techniques are described which enable accurate quantitative measurements of diffused atmospheric gases to be made using controlled light sources, accurate quantitative measurements of gas clouds relative to…
Research on numerical simulation technology about regional important pollutant diffusion of haze
NASA Astrophysics Data System (ADS)
Du, Boying; Ma, Yunfeng; Li, Qiangqiang; Wang, Qi; Hu, Qiongqiong; Bian, Yushan
2018-02-01
In order to analyze the formation of haze in Shenyang and the factors that affect the diffusion of pollutants, the simulation experiment adopted in this paper is based on the numerical model of WRF/CALPUFF coupling. Simulation experiment was conducted to select PM10 of Shenyang City in the period from March 1 to 8, and the PM10 in the regional important haze was simulated. The survey was conducted with more than 120 enterprises section the point of the emission source of this experiment. The contrastive data were analyzed with 11 air quality monitoring points, and the simulation results were compared. Analyze the contribution rate of each typical enterprise to the air quality, verify the correctness of the simulation results, and then use the model to establish the prediction model.
Tanik, A
2000-01-01
The six main drinking water reservoirs of Istanbul are under the threat of pollution due to rapid population increase, unplanned urbanisation and insufficient infrastructure. In contrast to the present land use profile, the environmental evaluation of the catchment areas reveals that point sources of pollutants, especially of domestic origin, dominate over those from diffuse sources. The water quality studies also support these findings, emphasising that if no substantial precautions are taken, there will be no possibility of obtaining drinking water from them. In this paper, under the light of the present status of the reservoirs, possible and probable short- and long-term protective measures are outlined for reducing the impact of point sources. Immediate precautions mostly depend on reducing the pollution arising from the existing settlements. Long-term measures mainly emphasise the preparation of new land use plans taking into consideration the protection of unoccupied lands. Recommendations on protection and control of the reservoirs are stated.
Assessing the spatial and temporal variations of water quality in lowland areas, Northern Germany
NASA Astrophysics Data System (ADS)
Lam, Q. D.; Schmalz, B.; Fohrer, N.
2012-05-01
SummaryThe pollution of rivers and streams with agro-chemical contaminants has become one of the most crucial environmental problems in the world. The assessment of spatial and temporal variations of water quality influenced by point and diffuse source pollution is necessary to manage the environment sustainably in various watershed scales. The overall objectives of this study were to assess the transferability of parameter sets between lowland catchments on different scales using the ecohydrological model SWAT (Soil and Water Assessment Tool) and to evaluate the temporal and spatial patterns of water quality in the whole catchments before and after implementation of best management practices (BMPs). The study area Kielstau catchment is located in Northern Germany as typical example of lowland - flood plain landscape. Sandy, loamy and peat soils are characteristic for this area. Land use is dominated by arable land and pasture. In this study we examined two catchment areas including Kielstau catchment 50 km2 and its subcatchment, namely Moorau, with the area of 7.6 km2. The water quality of these catchments is not only influenced by diffuse sources from agricultural areas but also by point sources from municipal wastewater treatment plants (WWTPs). Diffuse sources as well as punctual entries from the WWTPs are considered in the model set-up. For this study, the calibration and validation of the model were carried out in a daily time step for flow and nutrients. The results indicate that the parameter sets could be transferred in lowland catchments with similar environmental conditions. Shallow groundwater is the major contributor to total nitrate load in the stream accounting for about 93% of the total nitrate load, while only about 7% originates in surface runoff and lateral flow. The study also indicates that applying a spatially distributed modeling approach was an appropriate method to generate source maps showing the spatial distribution of TN load from hydrologic response units (HRUs) as well as from subbasins and to identify the crucial pollution areas within a watershed whose management practices can be improved to control more effectively nitrogen loading to water bodies.
River Export of Plastic from Land to Sea: A Global Modeling Approach
NASA Astrophysics Data System (ADS)
Siegfried, Max; Gabbert, Silke; Koelmans, Albert A.; Kroeze, Carolien; Löhr, Ansje; Verburg, Charlotte
2016-04-01
Plastic is increasingly considered a serious cause of water pollution. It is a threat to aquatic ecosystems, including rivers, coastal waters and oceans. Rivers transport considerable amounts of plastic from land to sea. The quantity and its main sources, however, are not well known. Assessing the amount of macro- and microplastic transport from river to sea is, therefore, important for understanding the dimension and the patterns of plastic pollution of aquatic ecosystems. In addition, it is crucial for assessing short- and long-term impacts caused by plastic pollution. Here we present a global modelling approach to quantify river export of plastic from land to sea. Our approach accounts for different types of plastic, including both macro- and micro-plastics. Moreover, we distinguish point sources and diffuse sources of plastic in rivers. Our modelling approach is inspired by global nutrient models, which include more than 6000 river basins. In this paper, we will present our modelling approach, as well as first model results for micro-plastic pollution in European rivers. Important sources of micro-plastics include personal care products, laundry, household dust and car tyre wear. We combine information on these sources with information on sewage management, and plastic retention during river transport for the largest European rivers. Our modelling approach may help to better understand and prevent water pollution by plastic , and at the same time serves as 'proof of concept' for future application on global scale.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tim, U.S.; Jolly, R.
1994-01-01
Considerable progress has been made in developing physically based, distributed parameter, hydrologic/water quality (HIWQ) models for planning and control of nonpoint-source pollution. The widespread use of these models is often constrained by the excessive and time-consuming input data demands and the lack of computing efficiencies necessary for iterative simulation of alternative management strategies. Recent developments in geographic information systems (GIS) provide techniques for handling large amounts of spatial data for modeling nonpoint-source pollution problems. Because a GIS can be used to combine information from several sources to form an array of model input data and to examine any combinations ofmore » spatial input/output data, it represents a highly effective tool for HiWQ modeling. This paper describes the integration of a distributed-parameter model (AGNPS) with a GIS (ARC/INFO) to examine nonpoint sources of pollution in an agricultural watershed. The ARC/INFO GIS provided the tools to generate and spatially organize the disparate data to support modeling, while the AGNPS model was used to predict several water quality variables including soil erosion and sedimentation within a watershed. The integrated system was used to evaluate the effectiveness of several alternative management strategies in reducing sediment pollution in a 417-ha watershed located in southern Iowa. The implementation of vegetative filter strips and contour buffer (grass) strips resulted in a 41 and 47% reduction in sediment yield at the watershed outlet, respectively. In addition, when the integrated system was used, the combination of the above management strategies resulted in a 71% reduction in sediment yield. In general, the study demonstrated the utility of integrating a simulation model with GIS for nonpoini-source pollution control and planning. Such techniques can help characterize the diffuse sources of pollution at the landscape level. 52 refs., 6 figs., 1 tab.« less
Locating the source of diffusion in complex networks by time-reversal backward spreading.
Shen, Zhesi; Cao, Shinan; Wang, Wen-Xu; Di, Zengru; Stanley, H Eugene
2016-03-01
Locating the source that triggers a dynamical process is a fundamental but challenging problem in complex networks, ranging from epidemic spreading in society and on the Internet to cancer metastasis in the human body. An accurate localization of the source is inherently limited by our ability to simultaneously access the information of all nodes in a large-scale complex network. This thus raises two critical questions: how do we locate the source from incomplete information and can we achieve full localization of sources at any possible location from a given set of observable nodes. Here we develop a time-reversal backward spreading algorithm to locate the source of a diffusion-like process efficiently and propose a general locatability condition. We test the algorithm by employing epidemic spreading and consensus dynamics as typical dynamical processes and apply it to the H1N1 pandemic in China. We find that the sources can be precisely located in arbitrary networks insofar as the locatability condition is assured. Our tools greatly improve our ability to locate the source of diffusion in complex networks based on limited accessibility of nodal information. Moreover, they have implications for controlling a variety of dynamical processes taking place on complex networks, such as inhibiting epidemics, slowing the spread of rumors, pollution control, and environmental protection.
Locating the source of diffusion in complex networks by time-reversal backward spreading
NASA Astrophysics Data System (ADS)
Shen, Zhesi; Cao, Shinan; Wang, Wen-Xu; Di, Zengru; Stanley, H. Eugene
2016-03-01
Locating the source that triggers a dynamical process is a fundamental but challenging problem in complex networks, ranging from epidemic spreading in society and on the Internet to cancer metastasis in the human body. An accurate localization of the source is inherently limited by our ability to simultaneously access the information of all nodes in a large-scale complex network. This thus raises two critical questions: how do we locate the source from incomplete information and can we achieve full localization of sources at any possible location from a given set of observable nodes. Here we develop a time-reversal backward spreading algorithm to locate the source of a diffusion-like process efficiently and propose a general locatability condition. We test the algorithm by employing epidemic spreading and consensus dynamics as typical dynamical processes and apply it to the H1N1 pandemic in China. We find that the sources can be precisely located in arbitrary networks insofar as the locatability condition is assured. Our tools greatly improve our ability to locate the source of diffusion in complex networks based on limited accessibility of nodal information. Moreover, they have implications for controlling a variety of dynamical processes taking place on complex networks, such as inhibiting epidemics, slowing the spread of rumors, pollution control, and environmental protection.
Finite Difference Formulation for Prediction of Water Pollution
NASA Astrophysics Data System (ADS)
Johari, Hanani; Rusli, Nursalasawati; Yahya, Zainab
2018-03-01
Water is an important component of the earth. Human being and living organisms are demand for the quality of water. Human activity is one of the causes of the water pollution. The pollution happened give bad effect to the physical and characteristic of water contents. It is not practical to monitor all aspects of water flow and transport distribution. So, in order to help people to access to the polluted area, a prediction of water pollution concentration must be modelled. This study proposed a one-dimensional advection diffusion equation for predicting the water pollution concentration transport. The numerical modelling will be produced in order to predict the transportation of water pollution concentration. In order to approximate the advection diffusion equation, the implicit Crank Nicolson is used. For the purpose of the simulation, the boundary condition and initial condition, the spatial steps and time steps as well as the approximations of the advection diffusion equation have been encoded. The results of one dimensional advection diffusion equation have successfully been used to predict the transportation of water pollution concentration by manipulating the velocity and diffusion parameters.
NASA Astrophysics Data System (ADS)
Clozel, Blandine
2017-04-01
As part of the Regional Health Plan for the Rhône-Alpes area (France), a cartography of soil contamination by persistent organic pollutants (dioxins/furans (PCDD/PCDF) and polychlorinated biphenyls (PCB)) was undertaken in order to define the background concentrations of soils located away from point source pollution. In the natural environment, PCDD/PCDF and PCB comes from air pollution and accumulate in the upper part of the soils. To define the background concentration of persistent organic pollutants from diffuse atmospheric origin in soils, sampling was carried out within the first 5 centimeters of soils that have been very little anthropized and untilled for more than 15 years. In such soils mixing and dilution of the pollutants is very limited. 170 samples were collected following a systematic plan of grid type (mesh of 8 x 8 km) in an area of 14 000km2, avoiding soil of high altitude and from urban area. Beyond their total concentration, the ratio of the congeners of PCBs (7 indicators and 12 dioxin-like) and of the 17 dioxins/furans was also used for interpretation. As expected, the concentrations in pollutants are globally lower in the rural zones than in the more industrialized ones. However, the pollutants are relatively enriched in valleys, confirming that the meteorological conditions and the local topography play a significant role in the repartition of the diffuse atmospheric pollution. For the vast majority of samples, even some of those presenting the highest total concentration, the ratio of the various congeners argues for an ancient origin of the contamination. All studies at the French or European level of the atmospheric concentration of organic pollutants indicate a progressive decrease in emissions of these contaminants for about 20 years. However, the soils have been receptors since a long time and such pollutants have accumulated. The congeners ratio give evolved signature of pollution indicating, on one hand, it is mainly due to past activities but, on the other hand, indicate that it will persist because of its high stability. These results show the importance of knowing the spatial distribution of the concentrations of PCDD/PCDF and PCB and taking into account the signature of their congeners when defining the reference value of background concentration which are applied to distinguish a recent point source pollution
Gömann, H; Kreins, P; Møller, C
2004-01-01
Among the numerous non-point sources of diffuse water pollution with nitrogen, agriculture is counted one of the main sources. The agricultural policies of the Agenda 2000 and a decoupling of direct payments for farmers from their production decisions are exemplarily evaluated as nitrogen reduction measures using the Regional Agricultural and Environmental Information System RAUMIS. The results show that until the target year 2010 the risk of diffuse pollution of water bodies with nitrogen is a regional problem in Germany. These problems are neither mitigated by the policies of Agenda 2000 nor by a decoupling of direct payments from production decisions of farmers. While total nitrogen surplus reduces considerably after a decoupling of direct payments due to decreases of land-use the nitrogen surplus on the remaining cultivated area increases resulting from structural changes. Granting the same amount of direct payments to farmers in both policy alternatives the agricultural sector income would be higher after a decoupling of direct payments opposed to the Agenda 2000 resulting from a more efficient allocation of inputs.
NASA Astrophysics Data System (ADS)
Vink, Rona; Behrendt, Horst
2002-11-01
Pollutant transport and management in the Rhine and Elbe basins is still of international concern, since certain target levels set by the international committees for protection of both rivers have not been reached. The analysis of the chain of emissions of point and diffuse sources to river loads will provide policy makers with a tool for effective management of river basins. The analysis of large river basins such as the Elbe and Rhine requires information on the spatial and temporal characteristics of both emissions and physical information of the entire river basin. In this paper, an analysis has been made of heavy metal emissions from various point and diffuse sources in the Rhine and Elbe drainage areas. Different point and diffuse pathways are considered in the model, such as inputs from industry, wastewater treatment plants, urban areas, erosion, groundwater, atmospheric deposition, tile drainage, and runoff. In most cases the measured heavy metal loads at monitoring stations are lower than the sum of the heavy metal emissions. This behaviour in large river systems can largely be explained by retention processes (e.g. sedimentation) and is dependent on the specific runoff of a catchment. Independent of the method used to estimate emissions, the source apportionment analysis of observed loads was used to determine the share of point and diffuse sources in the heavy metal load at a monitoring station by establishing a discharge dependency. The results from both the emission analysis and the source apportionment analysis of observed loads were compared and gave similar results. Between 51% (for Hg) and 74% (for Pb) of the total transport in the Elbe basin is supplied by inputs from diffuse sources. In the Rhine basin diffuse source inputs dominate the total transport and deliver more than 70% of the total transport. The diffuse hydrological pathways with the highest share are erosion and urban areas.
Impacts by point and diffuse micropollutant sources on the stream water quality at catchment scale
NASA Astrophysics Data System (ADS)
Petersen, M. F.; Eriksson, E.; Binning, P. J.; Bjerg, P. L.
2012-04-01
The water quality of surface waters is threatened by multiple anthropogenic pollutants and the large variety of pollutants challenges the monitoring and assessment of the water quality. The aim of this study was to characterize and quantify both point and diffuse sources of micropollutants impacting the water quality of a stream at catchment scale. Grindsted stream in western Jutland, Denmark was used as a study site. The stream passes both urban and agricultural areas and is impacted by severe groundwater contamination in Grindsted city. Along a 12 km reach of Grindsted stream, the potential pollution sources were identified including a pharmaceutical factory site with a contaminated old drainage ditch, two waste deposits, a wastewater treatment plant, overflow structures, fish farms, industrial discharges and diffuse agricultural and urban sources. Six water samples were collected along the stream and analyzed for general water quality parameters, inorganic constituents, pesticides, sulfonamides, chlorinated solvents, BTEXs, and paracetamol and ibuprofen. The latter two groups were not detected. The general water quality showed typical conditions for a stream in western Jutland. Minor impacts by releases of organic matter and nutrients were found after the fish farms and the waste water treatment plant. Nickel was found at concentrations 5.8 - 8.8 μg/l. Nine pesticides and metabolites of both agricultural and urban use were detected along the stream; among these were the two most frequently detected and some rarely detected pesticides in Danish water courses. The concentrations were generally consistent with other findings in Danish streams and in the range 0.01 - 0.09 μg/l; except for metribuzin-diketo that showed high concentrations up to 0.74 μg/l. The groundwater contamination at the pharmaceutical factory site, the drainage ditch and the waste deposits is similar in composition containing among others sulfonamides and chlorinated solvents (including vinyl chloride). Vinyl chloride concentrations surpassed Danish stream water quality criteria with a factor 10. The largest chemical impact occurs at the reach downstream Grindsted city revealing that the main contaminant groundwater discharge zones are found here. The contaminant plume from the factory site north of the stream is known to impact the stream whereas the impact by the old landfill south of the stream remains to be assessed. A conceptual model of the chemical impacts by the identified sources was made, and high impact was assigned to the contaminant plume from the factory site and to the diffuse sources of urban-use and agricultural pesticides. The next step will be a quantification of the sources, which will be presented at the conference.
Yang, Xue; Wang, Shaojian; Zhang, Wenzhong; Zhan, Dongsheng; Li, Jiaming
2017-04-15
China has received increased international criticism in recent years in relation to its air pollution levels, both in terms of the transmission of pollutants across international borders and the attendant adverse health effects being witnessed. Whilst existing research has examined the factors influencing ambient air pollutant concentrations, previous studies have failed to adequately explore the determinants of such concentrations from either a source or diffusion perspective. This study addressed both source (specifically, anthropogenic emissions) and diffusion (namely, meteorological conditions) indicators, in order to detect their respective impacts on the spatial variations seen in the distribution of air pollution. Spatial panel data for 113 major cities in China was processed using a range of global regression models-the ordinary least square model, the spatial lag model, and the spatial error model-as well as a local, geographic weighted regression (GWR) model. Results from the study suggest that in 2014, average SO 2 concentrations exceeded China's first-level target. The most polluted cities were found to be predominantly located in northern China, while less polluted cities were located in southern China. Global regression results indicated that precipitation exerts a significant effect on SO 2 reduction (p<0.001) and that a regional increase of 1mm in precipitation can reduce SO 2 concentrations by 0.026μg/m 3 . Both emission and temperature factors were found to aggravate SO 2 concentrations, although no such significant correlation was found in relation to wind speed. GWR results suggest that the association between SO 2 and its factors varied over space. Increased emissions were found to be able to produce more pollution in the northwest than in other parts of the country. Higher wind speeds and temperatures in northwestern areas were shown to reinforce SO 2 pollution, while in southern regions, they had the opposite effect. Further, increased precipitation was found to exert a greater inhibitory effect on SO 2 pollution in the country's northeast than that in other areas. Our findings could provide a detailed reference for formulating regionally specific emission reduction policies in China. Copyright © 2016 Elsevier B.V. All rights reserved.
Modeling diffuse sources of surface water contamination with plant protection products
NASA Astrophysics Data System (ADS)
Wendland, Sandra; Bock, Michael; Böhner, Jürgen; Lembrich, David
2015-04-01
Entries of chemical pollutants in surface waters are a serious environmental problem. Among water pollutants plant protection products (ppp) from farming practice are of major concern not only for water suppliers and environmental agencies, but also for farmers and industrial manufacturers. Lost chemicals no longer fulfill their original purpose on the field, but lead to severe damage of the environment and surface waters. Besides point-source inputs of chemical pollutants, the diffuse-source inputs from agricultural procedures play an important and not yet sufficiently studied role concerning water quality. The two most important factors for diffuse inputs are erosion and runoff. The latter usually occurs before erosion begins, and is thus often not visible in hindsight. Only if it has come to erosion, it is obvious to expect runoff in foresight at this area, too. In addition to numerous erosion models, there are also few applications to model runoff processes available. However, these conventional models utilize approximations of catchment parameters based on long-term average values or theoretically calculated concentration peaks which can only provide indications to relative amounts. Our study aims to develop and validate a simplified spatially-explicit dynamic model with high spatiotemporal resolution that enables to measure current and forecast runoff potential not only at catchment scale but field-differentiated. This method allows very precise estimations of runoff risks and supports risk reduction measures to be targeted before fields are treated. By focusing on water pathways occurring on arable land, targeted risk reduction measures like buffer strips at certain points and adapted ppp use can be taken early and pollution of rivers and other surface waters through transported pesticides, fertilizers and their products could be nearly avoided or largely minimized. Using a SAGA-based physical-parametric modeling approach, major factors influencing runoff (relief, soil properties, weather conditions and crop coverage) are represented. Water balance parameters are modeled in daily steps, taking into account relief determined discharge pathways, runoff velocity and number of field boundaries passed until receiving streams are reached. Model development is based on a comprehensive monitoring campaign at 3 smaller catchments in North Rhine-Westphalia (Germany), equipped with two gauges each, upstream and downstream, an optical Trios probe and four Isco-Samplers. The temporal high resolution monitoring of discharge, ppp, orthophosphate and nitrate-nitrogen enables an evaluation of runoff simulations in relation with rain events. First model results suggest that the simulation of surface runoff pathways enables a spatial-explicit identification of fields contributing to pollutant inputs. We assume that targeted actions on few fields will help solving the problem of diffuse inputs of ppp in our surface water to a considerable extent.
A Semi-Analytical Model for Dispersion Modelling Studies in the Atmospheric Boundary Layer
NASA Astrophysics Data System (ADS)
Gupta, A.; Sharan, M.
2017-12-01
The severe impact of harmful air pollutants has always been a cause of concern for a wide variety of air quality analysis. The analytical models based on the solution of the advection-diffusion equation have been the first and remain the convenient way for modeling air pollutant dispersion as it is easy to handle the dispersion parameters and related physics in it. A mathematical model describing the crosswind integrated concentration is presented. The analytical solution to the resulting advection-diffusion equation is limited to a constant and simple profiles of eddy diffusivity and wind speed. In practice, the wind speed depends on the vertical height above the ground and eddy diffusivity profiles on the downwind distance from the source as well as the vertical height. In the present model, a method of eigen-function expansion is used to solve the resulting partial differential equation with the appropriate boundary conditions. This leads to a system of first order ordinary differential equations with a coefficient matrix depending on the downwind distance. The solution of this system, in general, can be expressed in terms of Peano-baker series which is not easy to compute, particularly when the coefficient matrix becomes non-commutative (Martin et al., 1967). An approach based on Taylor's series expansion is introduced to find the numerical solution of first order system. The method is applied to various profiles of wind speed and eddy diffusivities. The solution computed from the proposed methodology is found to be efficient and accurate in comparison to those available in the literature. The performance of the model is evaluated with the diffusion datasets from Copenhagen (Gryning et al., 1987) and Hanford (Doran et al., 1985). In addition, the proposed method is used to deduce three dimensional concentrations by considering the Gaussian distribution in crosswind direction, which is also evaluated with diffusion data corresponding to a continuous point source.
Bloodworth, J W; Holman, I P; Burgess, P J; Gillman, S; Frogbrook, Z; Brown, P
2015-09-15
In recent years water companies have started to adopt catchment management to reduce diffuse pollution in drinking water supply areas. The heterogeneity of catchments and the range of pollutants that must be removed to meet the EU Drinking Water Directive (98/83/EC) limits make it difficult to prioritise areas of a catchment for intervention. Thus conceptual frameworks are required that can disaggregate the components of pollutant risk and help water companies make decisions about where to target interventions in their catchments to maximum effect. This paper demonstrates the concept of generalising pollutants in the same framework by reviewing key pollutant processes within a source-mobilisation-delivery context. From this, criteria are developed (with input from water industry professionals involved in catchment management) which highlights the need for a new water industry specific conceptual framework. The new CaRPoW (Catchment Risk to Potable Water) framework uses the Source-Mobilisation-Delivery concept as modular components of risk that work at two scales, source and mobilisation at the field scale and delivery at the catchment scale. Disaggregating pollutant processes permits the main components of risk to be ascertained so that appropriate interventions can be selected. The generic structure also allows for the outputs from different pollutants to be compared so that potential multiple benefits can be identified. CaRPow provides a transferable framework that can be used by water companies to cost-effectively target interventions under current conditions or under scenarios of land use or climate change. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Exposure to hazardous volatile pollutants back diffusing from automobile exhaust systems.
Rahman, Md Mahmudur; Kim, Ki-Hyun
2012-11-30
As back diffusion gases from automobiles are significant sources of in-vehicular pollution, we investigated eight automobiles, five for back diffusion (driving) measurements and three for reference conditions (non-driving). To characterize the back diffusion emission conditions, seven volatile organic compounds (VOC) and four carbonyl compounds (CCs) were measured along with dilution-to-threshold (D/T) ratio. The data obtained from back diffusion measurements were examined after having been divided into three subcategories: (i) driving and non-driving, (ii) with and without automobile upgrading (sealing the inner line), and (iii) differences in CO emission levels. Among the VOCs, the concentrations of toluene (T) was found to be the highest (range: 13.6-155 ppb), while benzene (0.19-1.47 ppb) was hardly distinguishable from its ambient levels. Other VOCs (xylene, trimethylbenzene, and styrene) were generally below <1 ppb. Unlike VOCs, the concentrations (ppb) of CCs were seen at fairly enhanced levels: 30.1-95 (formaldehyde), 34.6-87.2 (acetaldehyde), 4.56-34.7 (propionaldehyde), and 3.45-68.8 (butyraldehyde). The results of our study suggest that the back diffusion phenomenon, if occurring, can deteriorate in-vehicle air, especially with the most imminent health hazards from a compound such as formaldehyde in view of its exceedance pattern over common guidelines. Copyright © 2012 Elsevier B.V. All rights reserved.
Relationship between Air Pollution and Weather Conditions under Complicated Geographical conditions
NASA Astrophysics Data System (ADS)
Cheng, Q.; Jiang, P.; Li, M.
2017-12-01
Air pollution is one of the most serious issues all over the world, especially in megacities with constrained geographical conditions for air pollution diffusion. However, the dynamic mechanism of air pollution diffusion under complicated geographical conditions is still be confused. Researches to explore relationship between air pollution and weather conditions from the perspective of local atmospheric circulations can contribute more to solve such problem. We selected three megacities (Beijing, Shanghai and Guangzhou) under different geographical condition (mountain-plain transition region, coastal alluvial plain and coastal hilly terrain) to explore the relationship between air pollution and weather conditions. RDA (Redundancy analysis) model was used to analyze how the local atmospheric circulation acts on the air pollutant diffusion. The results show that there was a positive correlation between the concentration of air pollutants and air pressure, while temperature, precipitation and wind speed have negative correlations with the concentration of air pollutants. Furthermore, geographical conditions, such as topographic relief, have significant effects on the direction, path and intensity of local atmospheric circulation. As a consequence, air pollutants diffusion modes in different cities under various geographical conditions are diverse from each other.
Study on the total amount control of atmospheric pollutant based on GIS.
Wang, Jian-Ping; Guo, Xi-Kun
2005-08-01
To provide effective environmental management for total amount control of atmospheric pollutants. An atmospheric diffusion model of sulfur dioxide on the surface of the earth was established and tested in Shantou of Guangdong Province on the basis of an overall assessment of regional natural environment, social economic state of development, pollution sources and atmospheric environmental quality. Compared with actual monitoring results in a studied region, simulation values fell within the range of two times of error and were evenly distributed in the two sides of the monitored values. Predicted with the largest emission model method, the largest emission of sulfur dioxide would be 54,279.792 tons per year in 2010. The mathematical model established and revised on the basis of GIS is more rational and suitable for the regional characteristics of total amount control of air pollutants.
Convective Lofting Links Indian Ocean Air Pollution to Paradoxical South Atlantic Ozone Maxima
NASA Technical Reports Server (NTRS)
Chatfield, Robert B.; Guan, Hong; Thompson, Anne M.; Witte, Jacquelyn C.
2003-01-01
We describe a broad resolution of the "Atlantic Paradox" concerning the seasonal and geographic distribution of tropical tropospheric ozone. We describe periods of significant maximum tropospheric O3 for Jan.-April, 1999, exploiting satellite estimates and SHADOZ (Southern Hemisphere Additional Ozonesondes). Trajectory analyses connecting sondes and Total Tropospheric Ozone (TTO)O3 maps suggest a complex influence from the Indian Ocean: beginning with mixed combustion sources, then low level transport, cumulonimbus venting, and finally high-level transport to the west, with possible mixing over Africa. For the Jan.- March highest column-O3 periods in the Atlantic, distinct sounding peaks trace to specific NO sources, especially lightning, while in the same episodes, recurring every 30 or 60 days, more diffuse buildups of Indian-to-Atlantic pollution make important contributions.
Convective lofting links Indian Ocean air pollution to paradoxical South Atlantic ozone maxima
NASA Technical Reports Server (NTRS)
Chatfield, R. B.; Guan, H.; Thompson, A. M.; Witte, J. C.
2005-01-01
We describe a broad resolution of the Atlantic Parado concerning the seasonal and geographic distribution, of tropical tropospheric ozone. We highlight periods of significant maximum tropospheric O3 for Jan.- April, 1999, exploiting satellite estimates and SHADOZ (Southern Hemisphere Additional Ozonesondes). Trajectory analyses connecting sondes and Total Tropospheric Ozone (TTO) maps suggest a complex influence from the Indian Ocean: beginning with mixed combustion sources, then low level transport, cumulonimbus venting, possible stratospheric input, and finally high-level transport to the west, with possible mixing over Africa. For the Jan.-March highest column-O3 periods in the Atlantic, distinct sounding peaks trace to specific NO sources, especially lightning, while in the same episodes, recurring every 20-50 days, more diffuse buildups of Indian-to-Atlantic pollution make important contributions.
Napier, F; Jefferies, C; Heal, K V; Fogg, P; Arcy, B J D; Clarke, R
2009-01-01
SUDS are being increasingly employed to control highway runoff and have the potential to protect groundwater and surface water quality by minimising the risks of both point and diffuse sources of pollution. While these systems are effective at retaining polluted solids by filtration and sedimentation processes, less is known of the detail of pollutant behaviour within SUDS structures. This paper reports on investigations carried out as part of a co-ordinated programme of controlled studies and field measurements at soft-engineered SUDS undertaken in the UK, observing the accumulation and behaviour of traffic-related heavy metals, oil and PAHs. The field data presented were collected from two extended detention basins serving the M74 motorway in the south-west of Scotland. Additional data were supplied from an experimental lysimeter soil core leaching study. Results show that basin design influences pollutant accumulation and behaviour in the basins. Management and/or control strategies are discussed for reducing the impact of traffic-related pollutants on the aqueous environment.
Applications of MODIS satellite data and products for monitoring air quality in the state of Texas
NASA Astrophysics Data System (ADS)
Hutchison, Keith D.
The Center for Space Research (CSR), in conjunction with the Monitoring Operations Division (MOD) of the Texas Commission on Environmental Quality (TCEQ), is evaluating the use of remotely sensed satellite data to assist in monitoring and predicting air quality in Texas. The challenges of meeting air quality standards established by the US Environmental Protection Agency (US EPA) are impacted by the transport of pollution into Texas that originates from outside our borders and are cumulative with those generated by local sources. In an attempt to quantify the concentrations of all pollution sources, MOD has installed ground-based monitoring stations in rural regions along the Texas geographic boundaries including the Gulf coast, as well as urban regions that are the predominant sources of domestic pollution. However, analysis of time-lapse GOES satellite imagery at MOD, clearly demonstrates the shortcomings of using only ground-based observations for monitoring air quality across Texas. These shortcomings include the vastness of State borders, that can only be monitored with a large number of ground-based sensors, and gradients in pollution concentration that depend upon the location of the point source, the meteorology governing its transport to Texas, and its diffusion across the region. With the launch of NASA's MODerate resolution Imaging Spectroradiometer (MODIS), the transport of aerosol-borne pollutants can now be monitored over land and ocean surfaces. Thus, CSR and MOD personnel have applied MODIS data to several classes of pollution that routinely impact Texas air quality. Results demonstrate MODIS data and products can detect and track the migration of pollutants. This paper presents one case study in which continental haze from the northeast moved into the region and subsequently required health advisories to be issued for 150 counties in Texas. It is concluded that MODIS provides the basis for developing advanced data products that will, when used in conjunction with ground-based observations, create a cost-effective and accurate pollution monitoring system for the entire state of Texas.
Babu, Sundaram Ganesh; Ramalingam Vinoth; Neppolian, Bernaurdshaw; Dionysiou, Dionysios D; Ashokkumar, Muthupandian
2015-06-30
Diffused sunlight is found to be an effective light source for the efficient degradation and mineralization of organic pollutant (methyl orange as a probe) by sono-photocatalytic degradation using reduced graphene oxide (rGO) supported CuO-TiO2 photocatalyst. The prepared catalysts are characterized by XRD, XPS, UV-vis DRS, PL, photoelectrochemical, SEM-EDS and TEM. A 10 fold synergy is achieved for the first time by combining sonochemical and photocatalytic degradation under diffused sunlight. rGO loading augments the activity of bare CuO-TiO2 more than two fold. The ability of rGO in storing, transferring, and shuttling electrons at the heterojunction between TiO2 and CuO facilitates the separation of photogenerated electron-hole pairs, as evidenced by the photoluminescence results. The complete mineralization of MO and the by-products within a short span of time is confirmed by TOC analysis. Further, hydroxyl radical mediated degradation under diffused sunlight is confirmed by LC-MS. This system shows similar activity for the degradation of methylene blue and 4-chlorophenol indicating the versatility of the catalyst for the degradation of various pollutants. This investigation is likely to open new possibilities for the development of highly efficient diffused sunlight driven TiO2 based photocatalysts for the complete mineralization of organic contaminants. Copyright © 2015 Elsevier B.V. All rights reserved.
Modelling Urban diffuse pollution in groundwater
NASA Astrophysics Data System (ADS)
Jato, Musa; Smith, Martin; Cundy, Andrew
2017-04-01
Diffuse urban pollution of surface and ground waters is a growing concern in many cities and towns. Traffic-derived pollutants such as salts, heavy metals and polycyclic aromatic hydrocarbons (PAHs) may wash off road surfaces in soluble or particulate forms which later drain through soils and drainage systems into surface waters and groundwater. In Brighton, about 90% of drinking water supply comes from groundwater (derived from the Brighton Chalk block). In common with many groundwater sources the Chalk aquifer has been relatively extensively monitored and assessed for diffuse rural contaminants such as nitrate, but knowledge on the extent of contamination from road run-off is currently lacking. This project examines the transfer of traffic-derived contaminants from the road surface to the Chalk aquifer, via urban drainage systems. A transect of five boreholes have been sampled on a monthly basis and groundwater samples analysed to examine the concentrations of key, mainly road run-off derived, hydrocarbon and heavy metal contaminants in groundwater across the Brighton area. Trace concentrations of heavy metals and phenols have been observed in groundwater. Electrical conductivity changes in groundwater have also been used to assess local changes in ionic strength which may be associated with road-derived contaminants. This has been supplemented by systematic water and sediment sampling from urban gully pots, with further sampling planned from drainage and settlement ponds adjacent to major roads, to examine initial road to drainage system transport of major contaminants.
Study on gas diffusion emitted from different height of point source.
Yassin, Mohamed F
2009-01-01
The flow and dispersion of stack-gas emitted from different elevated point source around flow obstacles in an urban environment have been investigated, using computational fluid dynamics models (CFD). The results were compared with the experimental results obtained from the diffusion wind tunnel under different conditions of thermal stability (stable, neutral or unstable). The flow and dispersion fields in the boundary layer in an urban environment were examined with different flow obstacles. Gaseous pollutant was discharged in the simulated boundary layer over the flat area. The CFD models used for the simulation were based on the steady-state Reynolds-Average Navier-Stoke equations (RANS) with kappa-epsilon turbulence models; standard kappa-epsilon and RNG kappa-epsilon models. The flow and dispersion data measured in the wind tunnel experiments were compared with the results of the CFD models in order to evaluate the prediction accuracy of the pollutant dispersion. The results of the CFD models showed good agreement with the results of the wind tunnel experiments. The results indicate that the turbulent velocity is reduced by the obstacles models. The maximum dispersion appears around the wake region of the obstacles.
NASA Astrophysics Data System (ADS)
Fedorovich, E.; Thäter, J.
Results are presented from wind tunnel simulations of gaseous pollutant dispersion in the atmospheric convective boundary layer (CBL) capped by a temperature inversion. The experiments were performed in the thermally stratified wind tunnel of the University of Karlsruhe, Germany. In the tunnel, the case of horizontally evolving, sheared CBL is reproduced. This distinguishes the employed experimental setup from the preceding laboratory and numerical CBL dispersion studies. The diffusive and mixing properties of turbulence in the studied CBL case have been found to be essentially dependent on the stage of the CBL evolution. Effects of the point source elevation on the horizontal variability of the concentration field, and on the ground level concentration as function of distance from the source have been investigated. The applicability of bottom-up/top-down diffusion concept in the simulated CBL case has been evaluated. The influence of surface wind shear and capping inversion strength on the pollutant dispersion and turbulent exchange across the CBL top has been demonstrated. The imposed positive shear across the inversion has been identified as inhibitor of the CBL growth. Comparisons of concentration patterns from the wind tunnel with water tank data are presented.
NASA Astrophysics Data System (ADS)
Liu, X.; Liu, J.; Peng, W.; Wang, Y.
2007-05-01
In recent years, eutrophication has become one of the most serious of global water pollution problems, especially in reservoirs, which is menacing the security of domestic water supplies. As the unique drinking water source of Tianjin within the Haihe River basin of Hebei Province, China, YuQiao Reservoir has been polluted and its eutrophic state is serious. To make clear the physical and chemical relationship between transport and transformation of the polluted water, a model package was developed to compute the hydrodynamic field and mass transport processes including total nitrogen (TN) and total phosphorus (TP) for YuQiao Reservoir. The hydrodynamic model was driven by observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The mass transport and transformation processes of TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcings and external loadings, with the fluxes through the bottom of the reservoir, plant (algal) photosynthesis, and respiration as internal sources and sinks. The solution of these equations uses the finite volume method and alternating direction implicit (ADI) scheme. The model was calibrated and verified by using the data observed from YuQiao Reservoir in two different years. The results showed that in YuQiao Reservoir, the wind-driven current is an important style of lake current, while the water quality is decreasing from east to west because of the external polluted loadings. There was good agreement between the simulated and measured values. Advection is the main process driving the water quality impacts from the inflow river, and diffusion and biochemical processes dominate in center of the reservoir. So it is necessary to build a pre-pond to reduce the external loadings into the reservoir.
Thatcher, T L; Wilson, D J; Wood, E E; Craig, M J; Sextro, R G
2004-08-01
Scale modeling is a useful tool for analyzing complex indoor spaces. Scale model experiments can reduce experimental costs, improve control of flow and temperature conditions, and provide a practical method for pretesting full-scale system modifications. However, changes in physical scale and working fluid (air or water) can complicate interpretation of the equivalent effects in the full-scale structure. This paper presents a detailed scaling analysis of a water tank experiment designed to model a large indoor space, and experimental results obtained with this model to assess the influence of furniture and people in the pollutant concentration field at breathing height. Theoretical calculations are derived for predicting the effects from losses of molecular diffusion, small scale eddies, turbulent kinetic energy, and turbulent mass diffusivity in a scale model, even without Reynolds number matching. Pollutant dispersion experiments were performed in a water-filled 30:1 scale model of a large room, using uranine dye injected continuously from a small point source. Pollutant concentrations were measured in a plane, using laser-induced fluorescence techniques, for three interior configurations: unobstructed, table-like obstructions, and table-like and figure-like obstructions. Concentrations within the measurement plane varied by more than an order of magnitude, even after the concentration field was fully developed. Objects in the model interior had a significant effect on both the concentration field and fluctuation intensity in the measurement plane. PRACTICAL IMPLICATION: This scale model study demonstrates both the utility of scale models for investigating dispersion in indoor environments and the significant impact of turbulence created by furnishings and people on pollutant transport from floor level sources. In a room with no furniture or occupants, the average concentration can vary by about a factor of 3 across the room. Adding furniture and occupants can increase this spatial variation by another factor of 3.
NASA Astrophysics Data System (ADS)
Reaney, S. M.; Heathwaite, L.; Lane, S. N.; Buckley, C.
2007-12-01
Pollution of rivers from agricultural phosphorus is recognised as a significant global problem and is a major management challenge as it involves processes that are small in magnitude, distributed over large areas, operating at fine spatial scales and associated with certain land use types when they are well connected to the receiving waters. Whilst some of these processes have been addressed in terms of water quality forecasting models and field measurements, we lack effective tools to prioritise where action should be taken to remediate the diffuse pollution problem. From a management perspective, the required information is on 'what to do where' rather than absolute values. This change in focus opens up the problem to be considered in a probabilistic / relative framework rather than concentrating on absolute values. The SCIMAP risk management framework is based on the critical source area concept whereby a risk and a connection are required to generate a problem. Treatments of both surface and subsurface hydrological connectivity have been developed. The approach is based on the philosophy that for a point to be considered connected there needs to be a continuous flow path to the receiving water. This information is calculated by simulating the possible flow paths from the source cell to the receiving water and recording the required catchment wetness to allow flow along that route. This algorithm gives information on the ease at which each point in the landscape can export risk along surface and subsurface pathways to the receiving waters. To understand the annual dynamics of the locational diffuse P risk, a temporal risk framework has been developed. This risk framework accounts for land management activies within the agricultural calendar. These events include the application of fertiliser, the P additions from livestock and the offtake of P in crops. Changes to these risks can be made to investigate management options. The SCIMAP risk mapping framework has been applied to 12 catchments in England as part of the DEFRA / Environment Agency's Catchment Sensitive Farming programme. Result from these catchments will be presented.
Development and application of a reactive plume-in-grid model: evaluation over Greater Paris
NASA Astrophysics Data System (ADS)
Korsakissok, I.; Mallet, V.
2010-09-01
Emissions from major point sources are badly represented by classical Eulerian models. An overestimation of the horizontal plume dilution, a bad representation of the vertical diffusion as well as an incorrect estimate of the chemical reaction rates are the main limitations of such models in the vicinity of major point sources. The plume-in-grid method is a multiscale modeling technique that couples a local-scale Gaussian puff model with an Eulerian model in order to better represent these emissions. We present the plume-in-grid model developed in the air quality modeling system Polyphemus, with full gaseous chemistry. The model is evaluated on the metropolitan Île-de-France region, during six months (summer 2001). The subgrid-scale treatment is used for 89 major point sources, a selection based on the emission rates of NOx and SO2. Results with and without the subgrid treatment of point emissions are compared, and their performance by comparison to the observations on measurement stations is assessed. A sensitivity study is also carried out, on several local-scale parameters as well as on the vertical diffusion within the urban area. Primary pollutants are shown to be the most impacted by the plume-in-grid treatment. SO2 is the most impacted pollutant, since the point sources account for an important part of the total SO2 emissions, whereas NOx emissions are mostly due to traffic. The spatial impact of the subgrid treatment is localized in the vicinity of the sources, especially for reactive species (NOx and O3). Ozone is mostly sensitive to the time step between two puff emissions which influences the in-plume chemical reactions, whereas the almost-passive species SO2 is more sensitive to the injection time, which determines the duration of the subgrid-scale treatment. Future developments include an extension to handle aerosol chemistry, and an application to the modeling of line sources in order to use the subgrid treatment with road emissions. The latter is expected to lead to more striking results, due to the importance of traffic emissions for the pollutants of interest.
Li, Meng; Tang, Gui-qian; Huang, Jun; Liu, Zi-rui; An, Jun-lin; Wang, Yue-si
2015-06-01
Atmospheric mixing layer height (MLH) is one of the main factors affecting the atmospheric diffusion and plays an important role in air quality assessment and distribution of the pollutants. Based on the ceilometers data, this paper has made synchronous observation on MLH in Beijing-Tianjin-Hebei region (Beijing, Tianjin, Shijiazhuang and Qinhuangdao) in heavy polluted February 2014 and analyzed the respective overall change and its regional features. Results show that in February 2014,the average of mixing layer height in Qinhuangdao is the highest, up to 865 +/- 268 m, and in Shijiazhuang is the lowest (568 +/- 207 m), Beijing's and Tianjin's are in between, 818 +/- 319 m and 834 +/- 334 m respectively; Combined with the meteorological data, we find that radiation and wind speed are main factors of the mixing layer height; The relationship between the particle concentration and mixing layer height in four sites suggests that mixing layer is less than 800 m, concentration of fine particulate matter in four sites will exceed the national standard (GB 3095-2012, 75 microg x m(-3)). During the period of observation, the proportion of days that mixing layer is less than 800 m in Beijing, Tianjin, Shijiazhuang and Qinhuangdao are 50%, 43%, 80% and 50% respectively. Shijiazhuang though nearly formation contaminant concentration is high, within the atmospheric mixed layer pollutant load is not high. Unfavorable atmospheric diffusion conditions are the main causes of heavy pollution in Shijiazhuang for a long time. The results of the study are of great significance for cognitive Beijing-Tianjin-Hebei area pollution distribution, and can provide a scientific reference for reasonable distribution of regional pollution sources.
NASA Astrophysics Data System (ADS)
Lammel, G. P.; Heil, A.; Kukucka, P.; Meixner, F. X.; Mulder, M. D.; Prybilova, P.; Prokes, R.; Rusina, T. S.; Song, G. Z.; Vrana, B.
2015-12-01
The marine atmospheric environment is a receptor for persistent organic pollutants (POPs) which are advected from sources on land, primary, such as biomass burning by-products (PAHs, dioxins), and secondary, such as volatilization from contaminated soils (PCBs, pesticides). Primary sources do not exist in the marine environment, except for PAHs (ship engines) but following previous atmospheric deposition, the sea surface may turn to a secondary source by reversal of diffusive air-sea mass exchange. No monitoring is in place. We studied the vertical fluxes of a wide range of primary and secondary emitted POPs based on measurements in air and surface seawater at a remote coastal site in the eastern Mediterranean (2012). To this end, silicon rubbers were used as passive water samplers, vertical concentration gradients were determined in air and fluxes were quantified based on Eddy covariance. Diffusive air-sea exchange fluxes of hexachlorocyclohexanes (HCHs) and semivolatile PAHs were found close to phase equilibrium, except one PAH, retene, a wood burning tracer, was found seasonally net-volatilisational. Some PCBs, p,p'-DDE, penta- and hexachlorobenzene (PeCB, HCB) were mostly net-depositional, while PBDEs were net-volatilizational. Fluxes determined at a a remote coastal site ranged -33 - +2.4 µg m-2 d-1 for PAHs and -4.0 - +0.3 µg m-2 d-1for halogenated compounds (< 0 means net-deposition, > 0 means net-volatilization). It is concluded that nowadays in open seas more pollutants are undergoing reversal of the direction of air-sea exchange. Recgional fire activity records in combination with box model simulations suggest that deposition of retene during summer is followed by a reversal of air-sea exchange. The seawater surface as secondary source of pollution should be assessed based on flux measurements across seasons and over longer time periods.
Research on a Sudden Explosion and its Environmental Impact
NASA Astrophysics Data System (ADS)
Ye, Maosheng; Ma, Hui; Ni, Qingwei
2017-12-01
A sudden blast was chosen as the studied topic. Also, one computer based virtual experimentation was used to estimate the dimensional impact of initial pollutant plume from blasts. Self-made method using Mathcad code was used to generate the output for the period of the first tenth of a second (1deci-second) to 1minute (60s) of the blast at the point source. It also depicted long-range air pollution travel within the first 1 to 10 minutes. In the case study, it assumed an average directional diffusivity of 1720 m2s-1 which is about 25 per cent of the average generated speed of common explosives. The newly developed model revealed a plume cloud impact of 6.8×107µgm-3 in the first 1millisecond (0.01s) which decayed suddenly to a value of 1.7×107µgm-3 in the first 1decisecond (0.1s). The impact concentration at the point source by the end of the first second (1.0s) was 3.2×105µgm-3 which implied a 99.5% sudden decay when compared to 0.01s concentration value at the emission point source. Computerized experiments observed that air pollutants release from explosives/blasts were dispersed into the atmosphere in the first few seconds by forceful injection instead of by gradual dispersion as is the case with normal air pollutants plume releases.
Duo, Bu; Cui, Lulu; Wang, Zhenzhen; Li, Rui; Zhang, Liwu; Fu, Hongbo; Chen, Jianmin; Zhang, Huifang; Qiong, A
2018-01-01
Atmospheric pollutants including SO 2 , NO 2 , CO, O 3 and inhalable particulate matter (PM 2.5 and PM 10 ) were monitored continuously from March 2014 to February 2015 to investigate characteristics of air pollution at Lhasa, Tibetan Plateau. Species exhibited similar seasonal variations except O 3 , with the peaks in winter but low valleys in summer. The maximum O 3 concentration was observed in spring, followed by summer, autumn, and winter. The positive correlation between O 3 and PM 10 in spring indicated similar sources of them, and was assumed to be turbulent transport. Temperature was the dominant meteorological factor for most species in spring. High temperature accelerates O 3 photochemistry, and favors air disturbance which is conductive to dust resuspension in spring. Relative humidity (RH) and atmospheric pressure were the main meteorological factors in summer. RH showed negative correlations with species, while atmospheric pressure posed opposite situation. Wind speed (WS) was the dominant meteorological factor in autumn, the negative correlations between WS and species indicated diffusion by wind. Most species showed non-significant correlations with meteorological factors in winter, indicating the dependence of pollution on source emission rather than restriction by meteorology. Pollution weather character indicated that emissions were from biomass burning and dust suspension, and meteorological factors also played an important role. Air stream injection from the stratosphere was observed during O 3 pollution period. Air parcels from Southwest Asia were observed during air pollution period in winter. An enhancement in air pollutants such as O 3 would be expected in the future, more attention should be given to countermeasures for prevention of air pollution in the future. Copyright © 2017. Published by Elsevier B.V.
Mooney, C; Farrier, D
2002-01-01
Kangaroo Valley is a drinking water supply catchment for Kangaroo Valley village, parts of the Southern Highlands and Sydney. It is also a popular recreation area both for swimming and canoeing. Land use has traditionally been dominated by dairy farming but there has been significant and continuing development of land for hobby farms and rural residential subdivision. Dairy industry restructuring has affected the viability of some farms in the Valley and created additional pressure for subdivision. River health is a function of flows, water quality, riparian vegetation, geomorphology and aquatic habitat and riverine biota. River flows in the Kangaroo River are affected by water extraction and storage for urban water supply and extraction by commercial irrigators and riparian land holders which have a significant impact at low flows. Current water quality often does not meet ANZECC Guidelines for primary contact and recreation and the river is a poor source of raw drinking water. Key sources of contaminants are wastewater runoff from agriculture, and poorly performing on-site sewage management systems. Riparian vegetation, which is critical to the maintenance of in-stream ecosystems suffers from uncontrolled stock access and weed infestation. The management of land use and resulting diffuse pollution sources is critical to the long term health of the river. The Healthy Rivers Commission of New South Wales Independent Inquiry into the Shoalhaven River System Final Report July, 1999 found that the longer term protection of the health of the Kangaroo River is contingent upon achievement of patterns of land use that have regard to land capability and also to the capability of the river to withstand the impacts of inappropriate or poorly managed land uses. This micro case study of Kangaroo Valley examines the complex legal and administrative arrangements with particular reference to the management of diffuse pollution for river health. In the past, diffuse pollution has fallen through the gaps in legislation and its administration. Although water pollution legislation is broad enough to embrace diffuse pollution, in practice the Environment Protection Authority has focused on regulating point sources. Water legislation has traditionally been concerned with issues of water quantity rather than water quality. Legislation which allows agency intervention in relation to land degradation has grown from soil conservation roots, neglecting the flow-on effects upon water quality. Under the land use planning system existing land uses are protected from new regulatory requirements. A number of recent developments in NSW law and its administration have set the scene for addressing this past neglect. Water planning provisions in the Water Management Act 2000 have the potential to enable community based Water Management Committees to move away from a narrow focus on water quantity to the broader issues of river health, including water quality. Improved management of on-site sewage management systems is expected as a result of the Local Government (Approvals) Amendment (Sewage Management Regulation) 1998. A draft Regional Environmental Plan prepared for the Sydney Catchment Authority aims to improve the assessment of new development in terms of its impact on drinking water quality. It also moves away from an exclusive concern with controlling new development towards grappling with existing uses. Proposed amendments to the Environmental Planning and Assessment Act, 1979 as detailed in the White Paper, Plan First (2001) include the integration of imperatives derived from catchment strategies and water management plans into local land use plans.
Enhanced diffusion of pollutants by self-propulsion.
Zhao, Guanjia; Stuart, Emma J E; Pumera, Martin
2011-07-28
Current environmental models mostly account for the passive participation of pollutants in their environmental propagation. Here we demonstrate the paradigm-changing concept that pollutants can propagate themselves with a rate that is greater than the rate for standard molecular diffusion by five orders of magnitude. This journal is © the Owner Societies 2011
Koo, B K; O'Connell, P E
2006-04-01
The site-specific land use optimisation methodology, suggested by the authors in the first part of this two-part paper, has been applied to the River Kennet catchment at Marlborough, Wiltshire, UK, for a case study. The Marlborough catchment (143 km(2)) is an agriculture-dominated rural area over a deep chalk aquifer that is vulnerable to nitrate pollution from agricultural diffuse sources. For evaluation purposes, the catchment was discretised into a network of 1 kmx1 km grid cells. For each of the arable-land grid cells, seven land use alternatives (four arable-land alternatives and three grassland alternatives) were evaluated for their environmental and economic potential. For environmental evaluation, nitrate leaching rates of land use alternatives were estimated using SHETRAN simulations and groundwater pollution potential was evaluated using the DRASTIC index. For economic evaluation, economic gross margins were estimated using a simple agronomic model based on nitrogen response functions and agricultural land classification grades. In order to see whether the site-specific optimisation is efficient at the catchment scale, land use optimisation was carried out for four optimisation schemes (i.e. using four sets of criterion weights). Consequently, four land use scenarios were generated and the site-specifically optimised land use scenario was evaluated as the best compromise solution between long term nitrate pollution and agronomy at the catchment scale.
Space time modelling of air quality for environmental-risk maps: A case study in South Portugal
NASA Astrophysics Data System (ADS)
Soares, Amilcar; Pereira, Maria J.
2007-10-01
Since the 1960s, there has been a strong industrial development in the Sines area, on the southern Atlantic coast of Portugal, including the construction of an important industrial harbour and of, mainly, petrochemical and energy-related industries. These industries are, nowadays, responsible for substantial emissions of SO2, NOx, particles, VOCs and part of the ozone polluting the atmosphere. The major industries are spatially concentrated in a restricted area, very close to populated areas and natural resources such as those protected by the European Natura 2000 network. Air quality parameters are measured at the emissions' sources and at a few monitoring stations. Although air quality parameters are measured on an hourly basis, the lack of representativeness in space of these non-homogeneous phenomena makes even their representativeness in time questionable. Hence, in this study, the regional spatial dispersion of contaminants is also evaluated, using diffusive-sampler (Radiello Passive Sampler) campaigns during given periods. Diffusive samplers cover the entire space extensively, but just for a limited period of time. In the first step of this study, a space-time model of pollutants was built, based on a stochastic simulation-direct sequential simulation-with local spatial trend. The spatial dispersion of the contaminants for a given period of time-corresponding to the exposure time of the diffusive samplers-was computed by ordinary kriging. Direct sequential simulation was applied to produce equiprobable spatial maps for each day of that period, using the kriged map as a spatial trend and the daily measurements of pollutants from the monitoring stations as hard data. In the second step, the following environmental risk and costs maps were computed from the set of simulated realizations of pollutants: (i) maps of the contribution of each emission to the pollutant concentration at any spatial location; (ii) costs of badly located monitoring stations.
Boente, C; Matanzas, N; García-González, N; Rodríguez-Valdés, E; Gallego, J R
2017-09-01
The urban and peri-urban soils used for agriculture could be contaminated by atmospheric deposition or industrial releases, thus raising concerns about the potential risk to public health. Here we propose a method to evaluate potential soil pollution based on multivariate statistics, geostatistics (kriging), a novel soil pollution index, and bioavailability assessments. This approach was tested in two districts of a highly populated and industrialized city (Gijón, Spain). The soils showed anomalous content of several trace elements, such as As and Pb (up to 80 and 585 mg kg -1 respectively). In addition, factor analyses associated these elements with anthropogenic activity, whereas other elements were attributed to natural sources. Subsequent clustering also facilitated the differentiation between the northern area studied (only limited Pb pollution found) and the southern area (pattern of coal combustion, including simultaneous anomalies of trace elements and benzo(a)pyrene). A normalized soil pollution index (SPI) was calculated by kriging, using only the elements falling above threshold levels; therefore point-source polluted zones in the northern area and diffuse contamination in the south were identified. In addition, in the six mapping units with the highest SPIs of the fifty studied, we observed low bioavailability for most of the elements that surpassed the threshold levels. However, some anomalies of Pb contents and the pollution fingerprint in the central area of the southern grid call for further site-specific studies. On the whole, the combination of a multivariate (geo) statistic approach and a bioavailability assessment allowed us to efficiently identify sources of contamination and potential risks. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Janniche, Gry Sander; Spliid, Henrik; Albrechtsen, Hans-Jørgen
2012-10-01
Diffuse groundwater pollution from agricultural land use may impact the microbial groundwater community, which was investigated as Community-Level Physiological Profiles (CLPP) using EcoPlate™. Water was sampled from seven piezometers and a spring in a small agricultural catchment with diffuse herbicide and nitrate pollution. Based on the Shannon-Wiener and Simpson's diversity indices the diversity in the microbial communities was high. The response from the EcoPlates™ showed which substrates support groundwater bacteria, and all 31 carbon sources were utilized by organisms from at least one water sample. However, only nine carbon sources were utilized by all water samples: D-Mannitol, N-acetyl-D-glucosamine, putrescine, D-galacturonic acid, itaconic acid, 4-hydroxy benzoic acid, tween 40, tween 80, and L-asparagine. In all water samples the microorganisms preferred D-mannitol, D-galacturonic acid, tween 40, and 4-hydroxy benzoic acid as substrates, whereas none preferred 2-hydroxy benzoic acid, α-D-lactose, D,L-α-glycerol phosphate, α-ketobutyric acid, L-threonine and glycyl-L-glutamic acid. Principal Component Analysis of the CLPP's clustered the most agriculturally affected groundwater samples, indicating that the agricultural land use affects the groundwater microbial communities. Furthermore, the ability to mineralize atrazine and isoproturon, which have been used in the catchment, was also associated with this cluster.
Sharma, Brij Mohan; Nizzetto, Luca; Bharat, Girija K; Tayal, Shresth; Melymuk, Lisa; Sáňka, Ondřej; Přibylová, Petra; Audy, Ondřej; Larssen, Thorjørn
2015-11-01
Melting glaciers are natural redistributors of legacy airborne pollutants, affecting exposure of pristine proglacial environments. Our data shows that melting Himalayan glaciers can be major contributors of polychlorinated biphenyls (PCBs) and high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) for surface water in the Gangetic Plain during the dry season. Glacial emissions can exceed in some cases inputs from diffuse sources within the catchment. We analyzed air, deposition and river water in several sections along the Ganges River and its major headwaters. The predominant glacial origin of these contaminants in the Himalayan reach was demonstrated using air-water fugacity ratios and mass balance analysis. The proportion of meltwater emissions compared to pollutant discharge at downstream sections in the central part of the Gangetic Plain was between 2 and 200%. By remobilizing legacy pollutants from melting glaciers, climate change can enhance exposure levels over large and already heavily impacted regions of Northern India. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zhu, Lin; Li, Xun; Zhang, Chen; Duan, Zengqiang
2017-04-01
Heavily polluted sediment is becoming an important part of water pollution, and this situation is particularly acute in developing countries. Sediment has gradually changed from being the pollution adsorbent to the release source and has influenced the water environment and public health. In this study, we evaluated the pollutant distribution in sediment in a heavily polluted river and agitated the sediment in a heavily polluted river to re-suspend it and re-release pollutants. We found that the levels of chemical oxygen demand (COD), NH₄⁺-N, total nitrogen (TN), and total phosphorus (TP) in overlying water were significantly increased 60 min after agitation. The distribution of the pollutants in the sediment present high concentrations of pollutants congregated on top of the sediment after re-settling, and their distribution decreased with depth. Before agitation, the pollutants were randomly distributed throughout the sediment. Secondly, deep sediment aeration equipment (a micro-porous air diffuser) was installed during the process of sedimentation to study the remediation of the sediment by continuous aeration. The results revealed that deep sediment aeration after re-suspension significantly promoted the degradation of the pollutants both in overlying water and sediment, which also reduced the thickness of the sediment from 0.9 m to 0.6 m. Therefore, sediment aeration after suspension was efficient, and is a promising method for sediment remediation applications.
NASA Astrophysics Data System (ADS)
Strehmel, Alexander; Schmalz, Britta; Fohrer, Nicola
2016-11-01
The construction of the Three Gorges Dam in China and the subsequent impoundment of the Yangtze River have induced a major land use change in the Three Gorges Reservoir Region, which fosters increased inputs of sediment and nutrients from diffuse sources into the water bodies. Several government programs have been implemented to mitigate high sediment and nutrient loads to the reservoir. However, institutional weaknesses and a focus on economic development have so far widely counteracted the effectiveness of these programs. In this study, the eco-hydrological model soil and water assessment tool is used to assess the effects of changes in fertilizer amounts and the conditions of bench terraces in the Xiangxi catchment in the Three Gorges Reservoir Region on diffuse matter releases. With this, the study aims at identifying efficient management measures, which should have priority. The results show that a reduction of fertilizer amounts cannot reduce phosphorus loads considerably without inhibiting crop productivity. The condition of terraces in the catchment has a strong impact on soil erosion and phosphorus releases from agricultural areas. Hence, if economically feasible, programmes focusing on the construction and maintenance of terraces in the region should be implemented. Additionally, intercropping on corn fields as well as more efficient fertilization schemes for agricultural land were identified as potential instruments to reduce diffuse matter loads further. While the study was carried out in the Three Gorges Region, its findings may also beneficial for the reduction of water pollution in other mountainous areas with strong agricultural use.
Strehmel, Alexander; Schmalz, Britta; Fohrer, Nicola
2016-11-01
The construction of the Three Gorges Dam in China and the subsequent impoundment of the Yangtze River have induced a major land use change in the Three Gorges Reservoir Region, which fosters increased inputs of sediment and nutrients from diffuse sources into the water bodies. Several government programs have been implemented to mitigate high sediment and nutrient loads to the reservoir. However, institutional weaknesses and a focus on economic development have so far widely counteracted the effectiveness of these programs. In this study, the eco-hydrological model soil and water assessment tool is used to assess the effects of changes in fertilizer amounts and the conditions of bench terraces in the Xiangxi catchment in the Three Gorges Reservoir Region on diffuse matter releases. With this, the study aims at identifying efficient management measures, which should have priority. The results show that a reduction of fertilizer amounts cannot reduce phosphorus loads considerably without inhibiting crop productivity. The condition of terraces in the catchment has a strong impact on soil erosion and phosphorus releases from agricultural areas. Hence, if economically feasible, programmes focusing on the construction and maintenance of terraces in the region should be implemented. Additionally, intercropping on corn fields as well as more efficient fertilization schemes for agricultural land were identified as potential instruments to reduce diffuse matter loads further. While the study was carried out in the Three Gorges Region, its findings may also beneficial for the reduction of water pollution in other mountainous areas with strong agricultural use.
Implications of salinity pollution hotspots on agricultural production
NASA Astrophysics Data System (ADS)
Floerke, Martina; Fink, Julia; Malsy, Marcus; Voelker, Jeanette; Alcamo, Joseph
2016-04-01
Salinity pollution can have many negative impacts on water resources used for drinking, irrigation, and industrial purposes. Elevated concentrations of salinity in irrigation water can lead to decreased crop production or crop death and, thus, causing an economic problem. Overall, salinity pollution is a global problem but tends to be more severe in arid and semi-arid regions where the dilution capacity of rivers and lakes is lower and the use of irrigation higher. Particularly in these regions agricultural production is exposed to high salinity of irrigation water as insufficient water quality further reduces the available freshwater resources. According to the FAO, irrigated agriculture contributes about 40 percent of the total food production globally, and therefore, high salinity pollution poses a major concern for food production and food security. We use the WaterGAP3 modeling framework to simulate hydrological, water use, and water quality conditions on a global scale for the time period 1990 to 2010. The modeling framework is applied to simulate total dissolved solids (TDS) loadings and in-stream concentrations from different point and diffuse sources to get an insight on potential environmental impacts as well as risks to agricultural food production. The model was tested and calibrated against observed data from GEMStat and literature sources. Although global in scope, the focus of this study is on developing countries, i.e., in Africa, Asia, and Latin America, as these are most threatened by salinity pollution. Furthermore, insufficient water quality for irrigation and therefore restrictions in irrigation water use are examined, indicating limitations to crop production. Our results show that elevated salinity concentrations in surface waters mainly occur in peak irrigation regions as irrigated agriculture is not only the most relevant water use sector contributing to water abstractions, but also the dominant source of salinity pollution. Additionally, large metropolitan regions are initially loading hotspots and pollution, too, and prevention becomes important as point sources are dependent on sewer connection rates and treatment levels. In conclusion, this study provides a detailed picture of the spatial and temporal distribution of salinity pollution and identifies hotspot areas as well as the dominant sources. Furthermore, impacts of water quality degradation on agricultural production and food security are quantified, which aim for a better understanding of the risks for food security caused by water quality impairment.
Methane fluxes from tropical coastal lagoons surrounded bymangroves, Yucatán, Mexico
Chuang, Pei-Chuan; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A; Paytan, Adina
2017-01-01
Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m−2 d−1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.
Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico
NASA Astrophysics Data System (ADS)
Chuang, P.-C.; Young, M. B.; Dale, A. W.; Miller, L. G.; Herrera-Silveira, J. A.; Paytan, A.
2017-05-01
Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.
Adaptive hierarchical grid model of water-borne pollutant dispersion
NASA Astrophysics Data System (ADS)
Borthwick, A. G. L.; Marchant, R. D.; Copeland, G. J. M.
Water pollution by industrial and agricultural waste is an increasingly major public health issue. It is therefore important for water engineers and managers to be able to predict accurately the local behaviour of water-borne pollutants. This paper describes the novel and efficient coupling of dynamically adaptive hierarchical grids with standard solvers of the advection-diffusion equation. Adaptive quadtree grids are able to focus on regions of interest such as pollutant fronts, while retaining economy in the total number of grid elements through selective grid refinement. Advection is treated using Lagrangian particle tracking. Diffusion is solved separately using two grid-based methods; one is by explicit finite differences, the other a diffusion-velocity approach. Results are given in two dimensions for pure diffusion of an initially Gaussian plume, advection-diffusion of the Gaussian plume in the rotating flow field of a forced vortex, and the transport of species in a rectangular channel with side wall boundary layers. Close agreement is achieved with analytical solutions of the advection-diffusion equation and simulations from a Lagrangian random walk model. An application to Sepetiba Bay, Brazil is included to demonstrate the method with complex flows and topography.
Mirauda, Domenica; Ostoich, Marco
2018-02-23
The present study develops an integrated methodology combining the results of the water-quality classification, according to the Water Framework Directive 2000/60/EC-WFD, with those of a mathematical integrity model. It is able to analyse the potential anthropogenic impacts on the receiving water body and to help municipal decision-makers when selecting short/medium/long-term strategic mitigation actions to be performed in a territory. Among the most important causes of water-quality degradation in a river, the focus is placed on pollutants from urban wastewater. In particular, the proposed approach evaluates the efficiency and the accurate localisation of treatment plants in a basin, as well as the capacity of its river to bear the residual pollution loads after the treatment phase. The methodology is applied to a sample catchment area, located in northern Italy, where water quality is strongly affected by high population density and by the presence of agricultural and industrial activities. Nearly 10 years of water-quality data collected through official monitoring are considered for the implementation of the system. The sample basin shows different real and potential pollution conditions, according to the resilience of the river and surroundings, together with the point and diffuse pressure sources acting on the receiving body.
Application of a water quality model in the White Cart water catchment, Glasgow, UK.
Liu, S; Tucker, P; Mansell, M; Hursthouse, A
2003-03-01
Water quality models of urban systems have previously focused on point source (sewerage system) inputs. Little attention has been given to diffuse inputs and research into diffuse pollution has been largely confined to agriculture sources. This paper reports on new research that is aimed at integrating diffuse inputs into an urban water quality model. An integrated model is introduced that is made up of four modules: hydrology, contaminant point sources, nutrient cycling and leaching. The hydrology module, T&T consists of a TOPMODEL (a TOPography-based hydrological MODEL), which simulates runoff from pervious areas and a two-tank model, which simulates runoff from impervious urban areas. Linked into the two-tank model, the contaminant point source module simulates the overflow from the sewerage system in heavy rain. The widely known SOILN (SOIL Nitrate model) is the basis of nitrogen cycle module. Finally, the leaching module consists of two functions: the production function and the transfer function. The production function is based on SLIM (Solute Leaching Intermediate Model) while the transfer function is based on the 'flushing hypothesis' which postulates a relationship between contaminant concentrations in the receiving water course and the extent to which the catchment is saturated. This paper outlines the modelling methodology and the model structures that have been developed. An application of this model in the White Cart catchment (Glasgow) is also included.
Strategic guidelines for street canyon geometry to achieve sustainable street air quality
NASA Astrophysics Data System (ADS)
Chan, Andy T.; So, Ellen S. P.; Samad, Subash C.
This paper is concerned with the motion of air within the urban street canyon and is directed towards a deeper understanding of pollutant dispersion with respect to various simple canyon geometries and source positions. Taking into account the present days typical urban configurations, three principal flow regimes "isolated roughness flow", "skimming flow" and "wake interference flow" (Boundary Layer Climates, 2nd edition, Methuen, London) and their corresponding pollutant dispersion characteristics are studied for various canopies aspect ratios, namely relative height ( h2/ h1), canyon height to width ratio ( h/ w) and canyon length to height ratio ( l/ h). A field-size canyon has been analyzed through numerical simulations using the standard k- ɛ turbulence closure model. It is found that the pollutant transport and diffusion is strongly dependent upon the type of flow regime inside the canyon and exchange between canyon and the above roof air. Some rules of thumbs have been established to get urban canyon geometries for efficient dispersion of pollutants.
Capozzi, F; Giordano, S; Di Palma, A; Spagnuolo, V; De Nicola, F; Adamo, P
2016-04-01
In this paper we investigated the possibility to use moss bags to detect pollution inputs - metals, metalloids and polycyclic aromatic hydrocarbons (PAHs) - in sites chosen for their different land use (agricultural, urban/residential scenarios) and proximity to roads (sub-scenarios), in a fragmented conurbation of Campania (southern Italy). We focused on thirty-nine elements including rare earths. For most of them, moss uptake was higher in agricultural than in urban scenarios and in front road sites. Twenty PAHs were analyzed in a subset of agricultural sites; 4- and 5-ringed PAHs were the most abundant, particularly chrysene, fluoranthene and pyrene. Overall results indicated that investigated pollutants have a similar spatial distribution pattern over the entire study area, with road traffic and agricultural practices as the major diffuse pollution sources. Moss bags proved a very sensitive tool, able to discriminate between different land use scenarios and proximity to roads in a mixed rural-urban landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.
Yu, Soon Ju; Lee, Jae Yil; Ha, Sung Ryong
2010-01-01
This article aims to describe the influence of diffuse pollution on the temporal and spatial characteristics of natural organic matter (NOM) in a stratified dam reservoir, the Daecheong Dam, on the basis of intensive observation results and the dynamic water quality simulation using CE-QUAL-W2. Turbidity is regarded as a comprehensive representation of allochothonous organic matter from diffuse sources in storm season because the turbidity concentration showed reasonable significance in a statistical correlation with the UV absorbance at 254 nm and total phosphorus. CE-QUAL-W2 simulation results showed good consistency with the observed data in terms of dissolved organic matter (DOM) including refractory dissolved organic carbon (RDOC) and labile DOC and also well explained the internal movement of constituents and stratification phenomenon in the reservoir. Instead turbidity and NOM were related well in the upper region of the reservoir according to flow distance, gradually as changing to dissolved form of organic matter, RDOM affected organic matter concentration of reservoir water quality compared to turbidity. To control the increase of soluble organic matters in the dam reservoir, appropriate dam water discharge gate operation provided effective measurement. Because of the gate operation let avoid the accumulation of organic matter within a dam reservoir by shorten of turbid regime retention time.
Ouyang, Wei; Huang, Weijia; Wei, Peng; Hao, Fanghua; Yu, Yongyong
2016-06-15
Herbicides are a main source of agricultural diffuse pollution due to their wide application in tillage practices. The aim of this study is to optimize the control efficiency of the herbicide atrazine with the aid of modified soil amendments. The soil amendments were composed of a combination of biochar and gravel. The biochar was created from corn straw with a catalytic pyrolysis of ammonium dihydrogen phosphate. The leaching experiments under four rainfall conditions were measured for the following designs: raw soil, soil amended with gravel, biochar individually and together with gravel. The control efficiency of each design was also identified. With the designed equipment, the atrazine content in the contaminant load layer, gravel substrate layer, biochar amendment layer and soil layer was measured under four types of rainfall intensities (1.25 mm/h, 2.50 mm/h, 5.00 mm/h and 10.00 mm/h). Furthermore, the vertical distribution of atrazine in the soil sections was also monitored. The results showed that the herbicide leaching load increased under the highest rainfall intensity in all designs. The soil with the combination of gravel and biochar provided the highest control efficiency of 87.85% on atrazine when the additional proportion of biochar was 3.0%. The performance assessment under the four kinds of rainfall intensity conditions provided the guideline for the soil amendment configuration. The combination of gravel and biochar is recommended as an efficient method for controlling diffuse herbicide pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.
Ramus, Ksenia; Kopinke, Frank-Dieter; Georgi, Anett
2012-02-21
This study examines the effect of dissolved humic substances (DHS) on the rate of water-gas exchange of organic compounds under conditions where diffusion through the aqueous boundary layer is rate-determining. A synthetic surfactant was applied for comparison. Mass-transfer coefficients were determined from the rate of depletion of the model compounds by means of an apparatus containing a stirred aqueous solution with continuous purging of the headspace above the solution. In addition, experiments with continuous passive dosing of analytes into the water phase were conducted to simulate a system where thermodynamic activity of the chemical in the aqueous phase is identical in the presence and absence of DHS. The experimental results show that DHS and surfactants can affect water-gas exchange rates by the superposition of two mechanisms: (1) hydrodynamic effects due to surface film formation ("surface smoothing"), and (2) sorption-induced effects. Whether sorption accelerates or retards mass transfer depends on its effect on the thermodynamic activity of the pollutant in the aqueous phase. Mass transfer will be retarded if the activity (or freely dissolved concentration) of the pollutant is decreased due to sorption. If it remains unchanged (e.g., due to fast equilibration with a sediment acting as a large source phase), then DHS and surfactant micelles can act as an additional shuttle for the pollutants, enhancing the flux through the boundary layer.
Development and application of a reactive plume-in-grid model: evaluation over Greater Paris
NASA Astrophysics Data System (ADS)
Korsakissok, I.; Mallet, V.
2010-02-01
Emissions from major point sources are badly represented by classical Eulerian models. An overestimation of the horizontal plume dilution, a bad representation of the vertical diffusion as well as an incorrect estimate of the chemical reaction rates are the main limitations of such models in the vicinity of major point sources. The plume-in-grid method is a multiscale modeling technique that couples a local-scale Gaussian puff model with an Eulerian model in order to better represent these emissions. We present the plume-in-grid model developed in the air quality modeling system Polyphemus, with full gaseous chemistry. The model is evaluated on the metropolitan Île-de-France region, during six months (summer 2001). The subgrid-scale treatment is used for 89 major point sources, a selection based on the emission rates of NOx and SO2. Results with and without the subgrid treatment of point emissions are compared, and their performance by comparison to the observations at measurement stations is assessed. A sensitivity study is also carried out, on several local-scale parameters as well as on the vertical diffusion within the urban area. Primary pollutants are shown to be the most impacted by the plume-in-grid treatment, with a decrease in RMSE by up to about -17% for SO2 and -7% for NO at measurement stations. SO2 is the most impacted pollutant, since the point sources account for an important part of the total SO2 emissions, whereas NOx emissions are mostly due to traffic. The spatial impact of the subgrid treatment is localized in the vicinity of the sources, especially for reactive species (NOx and O3). Reactive species are mostly sensitive to the local-scale parameters, such as the time step between two puff emissions which influences the in-plume chemical reactions, whereas the almost-passive species SO2 is more sensitive to the injection time, which determines the duration of the subgrid-scale treatment. Future developments include an extension to handle aerosol chemistry, and an application to the modeling of line sources in order to use the subgrid treatment with road emissions. The latter is expected to lead to more striking results, due to the importance of traffic emissions for the pollutants of interest.
Huang, Haobo; Ouyang, Wei; Wu, Haotian; Liu, Hongbin; Andrea, Critto
2017-02-01
Analyses of the spatial-temporal distribution of diffuse pollution in agricultural regions are essential to the sustained management of water resources. Although nutrients, such as phosphorus fertilizers, can promote crop growth while improving soil fertility, excessive nutrient inputs can produce diffuse pollution, which may results in water quality degradation. The objective of this paper is to employ the SWAT (Soil and Water Assessment Tool) to estimate diffuse P effects on temporal and spatial distributions for a typical agricultural watershed and to identify the conjunct and independent influences of long-term land use and soil properties variation on diffuse P. With the validated model, the four-period simulation results (from 1979 to 2009) indicate that land use changes from agricultural development increased diffuse P yields. However, regarding updated soil properties, no significant differences of P yield were found between 1979 and 2009, demonstrating that impact of the cropland expansion were naturalized with soil property variations. An F-test was employed to assess the essentiality of all of the variables examined during the simulation period, and the test results indicated that diffuse P loading was more sensitive to soil properties than to land use. Before the P pollution control project about the land use optimization planning, it is more effective to distinguish the impacts of land use and soil properties. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Doucet, A.; Savard, M. M.; Bégin, C.; Ouarda, T. B.; Marion, J.
2010-12-01
The combined analyses of tree-ring δ13C, δ18O, δ15N, 206Pb/207Pb, 206Pb/204Pb and 206Pb/208Pb isotope ratios of three red spruce specimens from the Tantaré ecological reserve located 40 km northwest of Québec City (Canada) were studied with the aim of reconstructing environmental conditions and unravel past air-quality changes of the 1880-2007 period. To separate the tree-ring δ18O and δ13C patterns induced by natural conditions from those generated by anthropogenic perturbations, a linear regression was applied between the most explicative meteorological parameters and the isotopic series for the period of low pollution (1880 to 1909). The model equations were then applied to the most recent part of the series (1910-2007) to verify if climatic conditions have remained the main driver of the tree-ring isotopic variations. The good fit between the modeled and measured δ18O series for the entire studied period suggests that the assimilation of oxygen by red spruce trees is not significantly affected by pollution stress near Québec City. However, the deviation between the measured and modeled δ13C values for the 1944-2007 period indicates that diffuse pollution affected carbon assimilation by the investigated trees. To independently validate if atmospheric pollution could have generated the deviation between the measured and the estimated δ13C values, a linear regression was applied between the portion of the residual δ13C values and atmospheric pollution (Canadian fossil fuel proxy from 1958 to 2000). The nice fit between the modeled δ13C values from the combination of the two regression analyses based on climate and emission proxy strongly supports the hypothesis that there is a natural and an anthropogenic portion in the δ13C variations of the studied specimens. The short-term variations of the red spruce δ15N series are correlated with the instrumentally measured amounts of provincial N emissions for the 1990 to 2006 period (longest measurements available). Additionally, the long-term decrease of the δ15N series after 1956 is linked to the low isotopic values of NOx emitted by car exhausts, as expressed by the provincial number of cars which reflect the amount of transport-related N deposition at the provincial scale. The 208Pb/206Pb and 204Pb/206Pb ratios as a function of 206Pb/207Pb of the 1880-1919 period reflect a mixture of natural lead from the mineral soil horizon and mainly anthropogenic lead from north-eastern American coal combustion. The lower Pb ratios of the 1920-1989 period correlate well with the introduction of leaded additives to gasoline characterized by lower ratios relative to coal combustion. Inferring the lead sources of the 1990-2008 period is not as straightforward because lead can potentially derive from three main sources: coal combustion, burnt recycled material and natural lead present in soils. Our results show the great potential of tree-ring stable isotopes to record pollution events in the context of peri-urban diffuse pollution, and to prolong the pollution history in regions where direct measurements of pollutants only covers a relatively short period.
Valencia-Avellan, Magaly; Slack, Rebecca; Stockdale, Anthony; Mortimer, Robert John George
2017-08-16
Point and diffuse pollution from metal mining has led to severe environmental damage worldwide. Mine drainage is a significant problem for riverine ecosystems, it is commonly acidic (AMD), but neutral mine drainage (NMD) can also occur. A representative environment for studying metal pollution from NMD is provided by carboniferous catchments characterised by a circumneutral pH and high concentrations of carbonates, supporting the formation of secondary metal-minerals as potential sinks of metals. The present study focuses on understanding the mobility of metal pollution associated with historical mining in a carboniferous upland catchment. In the uplands of the UK, river water, sediments and spoil wastes were collected over a period of fourteen months, samples were chemically analysed to identify the main metal sources and their relationships with geological and hydrological factors. Correlation tests and principal component analysis suggest that the underlying limestone bedrock controls pH and weathering reactions. Significant metal concentrations from mining activities were measured for zinc (4.3 mg l -1 ), and lead (0.3 mg l -1 ), attributed to processes such as oxidation of mined ores (e.g. sphalerite, galena) or dissolution of precipitated secondary metal-minerals (e.g. cerussite, smithsonite). Zinc and lead mobility indicated strong dependence on biogeochemistry and hydrological conditions (e.g. pH and flow) at specific locations in the catchment. Annual loads of zinc and lead (2.9 and 0.2 tonnes per year) demonstrate a significant source of both metals to downstream river reaches. Metal pollution results in a large area of catchment having a depleted chemical status with likely effects on the aquatic ecology. This study provides an improved understanding of geological and hydrological processes controlling water chemistry, which is critical to assessing metal sources and mobilization, especially in neutral mine drainage areas.
EPA Office of Water (OW): 2002 SPARROW Total NP (Catchments)
SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling tool with output that allows the user to interpret water quality monitoring data at the regional and sub-regional scale. The model relates in-stream water-quality measurements to spatially referenced characteristics of watersheds, including pollutant sources and environmental factors that affect rates of pollutant delivery to streams from the land and aquatic, in-stream processing . The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and non-point (or ??diffuse??) sources on land to rivers and through the stream and river network. SPARROW estimates contaminant concentrations, loads (or ??mass,?? which is the product of concentration and streamflow), and yields in streams (mass of nitrogen and of phosphorus entering a stream per acre of land). It empirically estimates the origin and fate of contaminants in streams and receiving bodies, and quantifies uncertainties in model predictions. The model predictions are illustrated through detailed maps that provide information about contaminant loadings and source contributions at multiple scales for specific stream reaches, basins, or other geographic areas.
Refsgaard, A; Jacobsen, T; Jacobsen, B; Ørum, J-E
2007-01-01
The EU Water Framework Directive (WFD) requires an integrated approach to river basin management in order to meet environmental and ecological objectives. This paper presents concepts and full-scale application of an integrated modelling framework. The Ringkoebing Fjord basin is characterized by intensive agricultural production and leakage of nitrate constitute a major pollution problem with respect groundwater aquifers (drinking water), fresh surface water systems (water quality of lakes) and coastal receiving waters (eutrophication). The case study presented illustrates an advanced modelling approach applied in river basin management. Point sources (e.g. sewage treatment plant discharges) and distributed diffuse sources (nitrate leakage) are included to provide a modelling tool capable of simulating pollution transport from source to recipient to analyse the effects of specific, localized basin water management plans. The paper also includes a land rent modelling approach which can be used to choose the most cost-effective measures and the location of these measures. As a forerunner to the use of basin-scale models in WFD basin water management plans this project demonstrates the potential and limitations of comprehensive, integrated modelling tools.
NASA Astrophysics Data System (ADS)
Belis, Claudio A.; Pernigotti, Denise; Pirovano, Guido
2017-04-01
Source Apportionment (SA) is the identification of ambient air pollution sources and the quantification of their contribution to pollution levels. This task can be accomplished using different approaches: chemical transport models and receptor models. Receptor models are derived from measurements and therefore are considered as a reference for primary sources urban background levels. Chemical transport model have better estimation of the secondary pollutants (inorganic) and are capable to provide gridded results with high time resolution. Assessing the performance of SA model results is essential to guarantee reliable information on source contributions to be used for the reporting to the Commission and in the development of pollution abatement strategies. This is the first intercomparison ever designed to test both receptor oriented models (or receptor models) and chemical transport models (or source oriented models) using a comprehensive method based on model quality indicators and pre-established criteria. The target pollutant of this exercise, organised in the frame of FAIRMODE WG 3, is PM10. Both receptor models and chemical transport models present good performances when evaluated against their respective references. Both types of models demonstrate quite satisfactory capabilities to estimate the yearly source contributions while the estimation of the source contributions at the daily level (time series) is more critical. Chemical transport models showed a tendency to underestimate the contribution of some single sources when compared to receptor models. For receptor models the most critical source category is industry. This is probably due to the variety of single sources with different characteristics that belong to this category. Dust is the most problematic source for Chemical Transport Models, likely due to the poor information about this kind of source in the emission inventories, particularly concerning road dust re-suspension, and consequently the little detail about the chemical components of this source used in the models. The sensitivity tests show that chemical transport models show better performances when displaying a detailed set of sources (14) than when using a simplified one (only 8). It was also observed that an enhanced vertical profiling can improve the estimation of specific sources, such as industry, under complex meteorological conditions and that an insufficient spatial resolution in urban areas can impact on the capabilities of models to estimate the contribution of diffuse primary sources (e.g. traffic). Both families of models identify traffic and biomass burning as the first and second most contributing categories, respectively, to elemental carbon. The results of this study demonstrate that the source apportionment assessment methodology developed by the JRC is applicable to any kind of SA model. The same methodology is implemented in the on-line DeltaSA tool to support source apportionment model evaluation (http://source-apportionment.jrc.ec.europa.eu/).
NASA Astrophysics Data System (ADS)
Wu, Fengcheng; Xie, Pinhua; Li, Ang; Mou, Fusheng; Chen, Hao; Zhu, Yi; Zhu, Tong; Liu, Jianguo; Liu, Wenqing
2018-02-01
Recently, Chinese cities have suffered severe events of haze air pollution, particularly in the North China Plain (NCP). Investigating the temporal and spatial distribution of pollutants, emissions, and pollution transport is necessary to better understand the effect of various sources on air quality. We report on mobile differential optical absorption spectroscopy (mobile DOAS) observations of precursors SO2 and NO2 vertical columns in the NCP in the summer of 2013 (from 11 June to 7 July) in this study. The different temporal and spatial distributions of SO2 and NO2 vertical column density (VCD) over this area are characterized under various wind fields. The results show that transport from the southern NCP strongly affects air quality in Beijing, and the transport route, particularly SO2 transport on the route of Shijiazhuang-Baoding-Beijing, is identified. In addition, the major contributors to SO2 along the route of Shijiazhuang-Baoding-Beijing are elevated sources compared to low area sources for the route of Dezhou-Cangzhou-Tianjin-Beijing; this is found using the interrelated analysis between in situ and mobile DOAS observations during the measurement periods. Furthermore, the discussions on hot spots near the city of JiNan show that average observed width of polluted air mass is 11.83 and 17.23 km associated with air mass diffusion, which is approximately 60 km away from emission sources based on geometrical estimation. Finally, a reasonable agreement exists between the Ozone Monitoring Instrument (OMI) and mobile DOAS observations, with a correlation coefficient (R2) of 0.65 for NO2 VCDs. Both datasets also have a similar spatial pattern. The fitted slope of 0.55 is significantly less than unity, which can reflect the contamination of local sources, and OMI observations are needed to improve the sensitivities to the near-surface emission sources through improvements of the retrieval algorithm or the resolution of satellites.
Zhang, Zhao; Fukushima, Takehiko; Onda, Yuichi; Mizugaki, Shigeru; Gomi, Takashi; Kosugi, Ken'ichirou; Hiramatsu, Shinya; Kitahara, Hikaru; Kuraji, Koichiro; Terajima, Tomomi; Matsushige, Kazuo; Tao, Fulu
2008-02-01
Forest areas have been identified as important sources of nonpoint pollution in Japan. The managers must estimate stormwater quality and quantities from forested watersheds to develop effective management strategies. Therefore, stormwater runoff loads and concentrations of 10 constituents (total suspended solids, dissolved organic carbon, PO(4)-P, dissolved total phosphorus, total phosphorus, NH(4)-N, NO(2)-N, NO(3)-N, dissolved total nitrogen, and total nitrogen) for 72 events across five regions (Aichi, Kochi, Mie, Nagano, and Tokyo) were characterised. Most loads were significantly and positively correlated with stormwater variables (total event rainfall, event duration, and rainfall intensity), but most discharge-weighted event concentrations (DWECs) showed negative correlations with rainfall intensity. Mean water quality concentration during baseflow was correlated significantly with storm concentrations (r=0.41-0.77). Although all pollutant load equations showed high coefficients of determination (R(2)=0.55-0.80), no models predicted well pollutant concentrations, except those for the three N constituents (R(2)=0.59-0.67). Linear regressions to estimate stormwater concentrations and loads were greatly improved by regional grouping. The lower prediction capability of the concentration models for Mie, compared with the other four regions, indicated that other watershed or storm characteristics should be included in the prediction models. Significant differences among regions were found more frequently in concentrations than in loads for all constituents. Since baseflow conditions implied available pollutant sources for stormwater, the similar spatial characteristics of pollutant concentrations between baseflow and stormflow conditions were an important control for stormwater quality.
POLUTE. Forest Air Pollutant Uptake Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murphy, C.E. Jr.; Sinclair, T.R.
1992-02-13
POLUTE is a computer model designed to estimate the uptake of air pollutants by forests. The model utilizes submodels to describe atmospheric diffusion immediately above and within the canopy, and into the sink areas within or on the trees. The program implementing the model is general and can be used, with only minor changes, for any gaseous pollutant. The model provides an estimate describing the response of the vegetarian-atmosphere system to the environment as related to three types of processes: atmospheric diffusion, diffusion near and inside the absorbing plant, and the physical and chemical processes at the sink on ormore » within the plant.« less
NASA Astrophysics Data System (ADS)
Lutz, S. R.; van Meerveld, H. J.; Waterloo, M. J.; Broers, H. P.; van Breukelen, B. M.
2012-04-01
Concentration measurements are indispensable for the assessment of subsurface and surface water pollution by agrochemicals such as pesticides. However, monitoring data is often ambiguous and easily misinterpreted as a decrease in concentration could be caused by transformation, dilution or changes in the application of the pesticide. In this context, compound specific isotope analysis (CSIA) has recently emerged as a complementary monitoring technique. It is based on the measurement of the isotopic composition (e.g. δ13C and δ2H) of the contaminant. Since transformation processes are likely accompanied by isotope fractionation, thus a change in this composition, CSIA offers the opportunity to gain additional knowledge about transport and degradation processes as well as to track pollutants back to their sources. Isotopic techniques have not yet been applied in a comprehensive way in the analysis of catchment-wide organic pollution. We therefore incorporated fractionation processes associated with the fate of pesticides into the numerical flow and solute transport model HydroGeoSphere in order to assess the feasibility of CSIA within the context of catchment monitoring. The model was set up for a hypothetical hillslope transect which drains into a river. Reactive solute transport was driven by two pesticides applications within one year and actual data for rainfall and potential evapotranspiration from a meteorological station in the Netherlands. Degradation of the pesticide was assumed to take place at a higher rate under the prevailing oxic conditions in the topsoil than in deeper, anoxic subsurface layers. In terms of CSIA, these two degradation pathways were associated with different strengths of isotope fractionation for both hydrogen and carbon atoms. By simulating changes in δ13C and δ2H, the share of the oxic and the anoxic reaction on the overall degradation could be assessed. Model results suggest that CSIA is suitable for assessing degradation of diffuse agrochemical pollutants in a relatively simple hydrological system. The simulated shifts in isotopic signals are within a range that could be detected with current isotope analytics. Concentrations in the stream vary significantly only for a short period during and after intense rainfall events. In contrast, CSIA values reveal longer response times such that isotopic shifts are likely to be detected in samples with a coarser temporal resolution. Rainfall events which result in fast lateral subsurface transport from the pollution source to the stream can be separated from those that lead to pollution migration through deeper subsurface zones with much longer travel times. Two-dimensional CSIA highlights an increasing importance of the oxic reaction in the topsoil during the wetter period of the year. In order to examine to which extent CSIA is applicable for more complex hydrological systems, it is projected to simulate isotope fractionation in a 3-dimensional catchment featuring additional processes such as migration from several pollution sources or in-stream degradation.
The sources, impact and management of car park runoff pollution: a review.
Revitt, D Michael; Lundy, Lian; Coulon, Frédéric; Fairley, Martin
2014-12-15
Traffic emissions contribute significantly to the build-up of diffuse pollution loads on urban surfaces with their subsequent mobilisation and direct discharge posing problems for receiving water quality. This review focuses on the impact and mitigation of solids, metals, nutrients and organic pollutants in the runoff deriving from car parks. Variabilities in the discharged pollutant levels and in the potentials for pollutant mitigation complicate an impact assessment of car park runoff. The different available stormwater best management practices and proprietary devices are reported to be capable of reductions of between 20% and almost 100% for both suspended solids and a range of metals. This review contributes to prioritising the treatment options which can achieve the appropriate pollutant reductions whilst conforming to the site requirements of a typical car park. By applying different treatment scenarios to the runoff from a hypothetical car park, it is shown that optimal performance, in terms of ecological benefits for the receiving water, can be achieved using a treatment train incorporating permeable paving and bioretention systems. The review identifies existing research gaps and emphasises the pertinent management practices as well as design issues which are relevant to the mitigation of car park pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.
Yuan, Jie; Li, Siyue; Han, Xi; Chen, Qiuyang; Cheng, Xiaoli; Zhang, Quanfa
2017-08-15
There are increasing concerns in nitrogen (N) pollution worldwide, especially in aquatic ecosystems, and thus quantifying its sources in waterways is critical for pollution prevention and control. In this study, we investigated the spatio-temporal variabilities of inorganic N concentration (i.e., NO 3 - , NH 4 + ) and total dissolved N (TDN) and identified their sources in waters and suspended matters using an isotopical approach in the Jinshui River, a river with a length of 87km in the monsoon-climate region of China. The spatio-temporal inorganic N concentrations differed significantly along the longitudinal gradient in the river network. The NO 3 - , NH 4 + and TDN concentrations ranged from 0.02 to 1.12mgl -1 , 0.03 to 4.28mgl -1 , and 0.33 to 2.78mgl -1 , respectively. The 15 N tracing studies demonstrated that N in suspended organic matter was in the form of suspended particulate nitrogen (SPN) and was primarily from atmospheric deposition and agricultural fertilizer. In contrast, N in stream waters was mainly in the form of nitrate and was from atmospheric deposition, fertilizers, soil, and sewage. Meanwhile, both δ 15 N-SPN and δ 15 N-NO 3 - peaked in the rainy season (i.e., July) because of higher terrigenous sources via rain runoff, demonstrating the dominant diffusive N sources in the catchment. Thus, our results could provide critical information on N pollution control and sustainable watershed management of the riverine ecosystem in monsoon-climate region. Copyright © 2017 Elsevier B.V. All rights reserved.
Geng, Runzhe; Wang, Xiaoyan; Sharpley, Andrew N.; Meng, Fande
2015-01-01
Best management practices (BMPs) for agricultural diffuse pollution control are implemented at the field or small-watershed scale. However, the benefits of BMP implementation on receiving water quality at multiple spatial is an ongoing challenge. In this paper, we introduce an integrated approach that combines risk assessment (i.e., Phosphorus (P) index), model simulation techniques (Hydrological Simulation Program–FORTRAN), and a BMP placement tool at various scales to identify the optimal location for implementing multiple BMPs and estimate BMP effectiveness after implementation. A statistically significant decrease in nutrient discharge from watersheds is proposed to evaluate the effectiveness of BMPs, strategically targeted within watersheds. Specifically, we estimate two types of cost-effectiveness curves (total pollution reduction and proportion of watersheds improved) for four allocation approaches. Selection of a ‘‘best approach” depends on the relative importance of the two types of effectiveness, which involves a value judgment based on the random/aggregated degree of BMP distribution among and within sub-watersheds. A statistical optimization framework is developed and evaluated in Chaohe River Watershed located in the northern mountain area of Beijing. Results show that BMP implementation significantly (p >0.001) decrease P loss from the watershed. Remedial strategies where BMPs were targeted to areas of high risk of P loss, deceased P loads compared with strategies where BMPs were randomly located across watersheds. Sensitivity analysis indicated that aggregated BMP placement in particular watershed is the most cost-effective scenario to decrease P loss. The optimization approach outlined in this paper is a spatially hierarchical method for targeting nonpoint source controls across a range of scales from field to farm, to watersheds, to regions. Further, model estimates showed targeting at multiple scales is necessary to optimize program efficiency. The integrated model approach described that selects and places BMPs at varying levels of implementation, provides a new theoretical basis and technical guidance for diffuse pollution management in agricultural watersheds. PMID:26313561
Geng, Runzhe; Wang, Xiaoyan; Sharpley, Andrew N; Meng, Fande
2015-01-01
Best management practices (BMPs) for agricultural diffuse pollution control are implemented at the field or small-watershed scale. However, the benefits of BMP implementation on receiving water quality at multiple spatial is an ongoing challenge. In this paper, we introduce an integrated approach that combines risk assessment (i.e., Phosphorus (P) index), model simulation techniques (Hydrological Simulation Program-FORTRAN), and a BMP placement tool at various scales to identify the optimal location for implementing multiple BMPs and estimate BMP effectiveness after implementation. A statistically significant decrease in nutrient discharge from watersheds is proposed to evaluate the effectiveness of BMPs, strategically targeted within watersheds. Specifically, we estimate two types of cost-effectiveness curves (total pollution reduction and proportion of watersheds improved) for four allocation approaches. Selection of a ''best approach" depends on the relative importance of the two types of effectiveness, which involves a value judgment based on the random/aggregated degree of BMP distribution among and within sub-watersheds. A statistical optimization framework is developed and evaluated in Chaohe River Watershed located in the northern mountain area of Beijing. Results show that BMP implementation significantly (p >0.001) decrease P loss from the watershed. Remedial strategies where BMPs were targeted to areas of high risk of P loss, deceased P loads compared with strategies where BMPs were randomly located across watersheds. Sensitivity analysis indicated that aggregated BMP placement in particular watershed is the most cost-effective scenario to decrease P loss. The optimization approach outlined in this paper is a spatially hierarchical method for targeting nonpoint source controls across a range of scales from field to farm, to watersheds, to regions. Further, model estimates showed targeting at multiple scales is necessary to optimize program efficiency. The integrated model approach described that selects and places BMPs at varying levels of implementation, provides a new theoretical basis and technical guidance for diffuse pollution management in agricultural watersheds.
Diffusive flux of PAHs across sediment-water and water-air interfaces at urban superfund sites.
Minick, D James; Anderson, Kim A
2017-09-01
Superfund sites may be a source of polycyclic aromatic hydrocarbons (PAHs) to the surrounding environment. These sites can also act as PAH sinks from present-day anthropogenic activities, especially in urban locations. Understanding PAH transport across environmental compartments helps to define the relative contributions of these sources and is therefore important for informing remedial and management decisions. In the present study, paired passive samplers were co-deployed at sediment-water and water-air interfaces within the Portland Harbor Superfund Site and the McCormick and Baxter Superfund Site. These sites, located along the Willamette River (Portland, OR, USA), have PAH contamination from both legacy and modern sources. Diffusive flux calculations indicate that the Willamette River acts predominantly as a sink for low molecular weight PAHs from both the sediment and the air. The sediment was also predominantly a source of 4- and 5-ring PAHs to the river, and the river was a source of these same PAHs to the air, indicating that legacy pollution may be contributing to PAH exposure for residents of the Portland urban center. At the remediated McCormick and Baxter Superfund Site, flux measurements highlight locations within the sand and rock sediment cap where contaminant breakthrough is occurring. Environ Toxicol Chem 2017;36:2281-2289. © 2017 SETAC. © 2017 SETAC.
Evaluation of constructed wetlands by wastewater purification ability and greenhouse gas emissions.
Gui, P; Inamori, R; Matsumura, M; Inamori, Y
2007-01-01
Domestic wastewater is a significant source of nitrogen and phosphorus, which cause lake eutrophication. Among the wastewater treatment technologies, constructed wetlands are a promising low-cost means of treating point and diffuse sources of domestic wastewater in rural areas. However, the sustainable operation of constructed wetland treatment systems depends upon a high rate conversion of organic and nitrogenous loading into their metabolic gaseous end products, such as N2O and CH4. In this study, we examined and compared the performance of three typical types of constructed wetlands: Free Water Surface (FWS), Subsurface Flow (SF) and Vertical Flow (VF) wetlands. Pollutant removal efficiency and N2O and CH4 emissions were assessed as measures of performance. We found that the pollutant removal rates and gas emissions measured in the wetlands exhibited clear seasonal changes, and these changes were closely associated with plant growth. VF wetlands exhibited stable removal of organic pollutants and NH3-N throughout the experiment regardless of season and showed great potential for CH4 adsorption. SF wetlands showed preferable T-N removal performance and a lower risk of greenhouse gas emissions than FWS wetlands. Soil oxidation reduction potential (ORP) analysis revealed that water flow structure and plant growth influenced constructed wetland oxygen transfer, and these variations resulted in seasonal changes of ORP distribution inside wetlands that were accompanied by fluctuations in pollutant removal and greenhouse gas emissions.
POLUTE; forest air pollutant uptake model. [IBM360,370; CSMP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murphy, C.E.
POLUTE is a computer model designed to estimate the uptake of air pollutants by forests. The model utilizes submodels to describe atmospheric diffusion immediately above and within the canopy, and into the sink areas within or on the trees. The program implementing the model is general and can be used, with only minor changes, for any gaseous pollutant. The model provides an estimate describing the response of the vegetarian-atmosphere system to the environment as related to three types of processes: atmospheric diffusion, diffusion near and inside the absorbing plant, and the physical and chemical processes at the sink on ormore » within the plant.IBM360,370; CSMP; OS/370.« less
Wu, Wen; Wu, Zhouhu; Song, Zhiwen
2017-07-01
Prediction of the pollutant mixing zone (PMZ) near the discharge outfall in Huangshaxi shows large error when using the methods based on the constant lateral diffusion assumption. The discrepancy is due to the lack of consideration of the diffusion coefficient variation. The variable lateral diffusion coefficient is proposed to be a function of the longitudinal distance from the outfall. Analytical solution of the two-dimensional advection-diffusion equation of a pollutant is derived and discussed. Formulas to characterize the geometry of the PMZ are derived based on this solution, and a standard curve describing the boundary of the PMZ is obtained by proper choices of the normalization scales. The change of PMZ topology due to the variable diffusion coefficient is then discussed using these formulas. The criterion of assuming the lateral diffusion coefficient to be constant without large error in PMZ geometry is found. It is also demonstrated how to use these analytical formulas in the inverse problems including estimating the lateral diffusion coefficient in rivers by convenient measurements, and determining the maximum allowable discharge load based on the limitations of the geometrical scales of the PMZ. Finally, applications of the obtained formulas to onsite PMZ measurements in Huangshaxi present excellent agreement.
Mghirbi, Oussama; Bord, Jean-Paul; Le Grusse, Philippe; Mandart, Elisabeth; Fabre, Jacques
2018-03-08
Faced with health, environmental, and socio-economic issues related to the heavy use of pesticides, diffuse phytosanitary pollution becomes a major concern shared by all the field actors. These actors, namely the farmers and territorial managers, have expressed the need to implement decision support tools for the territorial management of diffuse pollution resulting from the plant protection practices and their impacts. To meet these steadily increasing requests, a cartographic analysis approach was implemented based on GIS which allows the spatialization of the diffuse pollution impacts related to plant protection practices on the Etang de l'Or catchment area in the South of France. Risk mapping represents a support-decision tool that enables the different field actors to identify and locate vulnerable areas, so as to determine action plans and agri-environmental measures depending on the context of the natural environment. This work shows that mapping is helpful for managing risks related to the use of pesticides in agriculture by employing indicators of pressure (TFI) and risk on the applicator's health (IRSA) and on the environment (IRTE). These indicators were designed to assess the impact of plant protection practices at various spatial scales (field, farm, etc.). The cartographic analysis of risks related to plant protection practices shows that diffuse pollution is unequally located in the North (known for its abundant garrigues and vineyards) and in the South of the Etang de l'Or catchment area (the Mauguio-Lunel agricultural plain known for its diversified cropping systems). This spatial inequity is essentially related to land use and agricultural production system. Indeed, the agricultural lands cover about 60% of the total catchment area. Consequently, this cartographic analysis helps the territorial actors with the implementation of strategies for managing risks of diffuse pollution related to pesticides use in agriculture, based on environmental and socio-economic issues and the characteristics of the natural environment.
NASA Astrophysics Data System (ADS)
Strada, Susanna; Unger, Nadine
2016-04-01
A global Earth system model is applied to quantify the impacts of direct anthropogenic aerosol effective radiative forcing on gross primary productivity (GPP) and isoprene emission. The impacts of different pollution aerosol sources (anthropogenic, biomass burning, and non-biomass burning) are investigated by performing sensitivity experiments. The model framework includes all known light and meteorological responses of photosynthesis, but uses fixed canopy structures and phenology. On a global scale, our results show that global land carbon fluxes (GPP and isoprene emission) are not sensitive to pollution aerosols, even under a global decline in surface solar radiation (direct + diffuse) by ˜ 9 %. At a regional scale, GPP and isoprene emission show a robust but opposite sensitivity to pollution aerosols in regions where forested canopies dominate. In eastern North America and Eurasia, anthropogenic pollution aerosols (mainly from non-biomass burning sources) enhance GPP by +5-8 % on an annual average. In the northwestern Amazon Basin and central Africa, biomass burning aerosols increase GPP by +2-5 % on an annual average, with a peak in the northwestern Amazon Basin during the dry-fire season (+5-8 %). The prevailing mechanism varies across regions: light scattering dominates in eastern North America, while a reduction in direct radiation dominates in Europe and China. Aerosol-induced GPP productivity increases in the Amazon and central Africa include an additional positive feedback from reduced canopy temperatures in response to increases in canopy conductance. In Eurasia and northeastern China, anthropogenic pollution aerosols drive a decrease in isoprene emission of -2 to -12 % on an annual average. Future research needs to incorporate the indirect effects of aerosols and possible feedbacks from dynamic carbon allocation and phenology.
Rinaudo, J-D; Arnal, C; Blanchin, R; Elsass, P; Meilhac, A; Loubier, S
2005-01-01
This paper presents an assessment of the costs of diffuse groundwater pollution by nitrates and pesticides for the industrial and the drinking water sectors in the Upper Rhine valley, France. Pollution costs which occurred between 1988 and 2002 are described and assessed using the avoidance cost method. Geo-statistical methods (kriging) are then used to construct three scenarios of nitrate concentration evolution. The economic consequences of each scenario are then assessed. The estimates obtained are compared with the results of a contingent valuation study carried out in the same study area ten years earlier.
NASA Astrophysics Data System (ADS)
Destouni, G.
2008-12-01
Excess nutrient and pollutant releases from various point and diffuse sources at and below the land surface, associated with land use, industry and households, pose serious eutrophication and pollution risks to inland and coastal water ecosystems worldwide. These risks must be assessed, for instance according to the EU Water Framework Directive (WFD). The WFD demands economically efficient, basin-scale water management for achieving and maintaining good physico-chemical and ecological status in all the inland and coastal waters of EU member states. This paper synthesizes a series of hydro-biogeochemical and linked economic efficiency studies of basin-scale waterborne nutrient and pollutant flows, the development over the last decades up to the current levels of these flows, the main monitoring and modelling uncertainties associated with their quantification, and the effectiveness and economic efficiency of different possible abatement strategies for abating them in order to meet WFD requirements and other environmental goals on local, national and international levels under climate and other regional change. The studies include different Swedish and Baltic Sea drainage basins. Main findings include quantification of near-coastal monitoring gaps and long-term nutrient and pollutant memory in the subsurface (soil-groundwater-sediment) water systems of drainage basins. The former may significantly mask nutrient and pollutant loads to the sea while the latter may continue to uphold large loads to inland and coastal waters long time after source mitigation. A methodology is presented for finding a rational trade-off between the two resource-demanding options to reduce, or accept and explicitly account for the uncertainties implied by these monitoring gaps and long-term nutrient-pollution memories and time lags, and other knowledge, data and model uncertainties that limit the effectiveness and efficiency of water pollution and eutrophication management.
A two-dimensional, finite-difference model simulating a highway has been developed which is able to handle linear and nonlinear chemical reactions. Transport of the pollutants is accomplished by use of an upstream-flux-corrected algorithm developed at the Naval Research Laborator...
Groundwater Nitrate Contamination Risk Assessment in Canicattì area (Sicily)
NASA Astrophysics Data System (ADS)
Pisciotta, Antonino; Cusimano, Gioacchino; Favara, Rocco
2010-05-01
Groundwaters play a dominant role in the Sicily, because as most part of Mediterranean countries this island is interested by the phenomenon of desertification and the quality of the groundwater reservoir is one of the most important aim for the management policy strategies. During last decade most of the Italian regions the nitrate levels in river and groundwaters have increased gradually over mainly as a consequence of large-scale agricultural application of manure and fertilizers, thereby threatening drinking water quality. The excessive use of chemicals and fertilizers increases the risk to pollution of surface and groundwater from diffuse source, an important reflex to human health and the environment. The studied area is located in Canicattì (central Sicily, Italy), the current land use (grape, olive grove and almond) is the main source of groundwater pollution. In order to investigate the effect of the over farming on the groundwater quality we report the study on the potential risk of contamination from nitrate of agricultural origin through the join of the application of two parametric methods: the IPNOA method (the intrinsic nitrate contamination risk from Agricultural sources) applied to define the Nitrate Vulnerable Zones and the SINTACS method applied to determine the aquifer vulnerability to contamination.
NASA Astrophysics Data System (ADS)
McKnight, Ursula S.; Sonne, Anne T.; Rasmussen, Jes J.; Traunspurger, Walter; Höss, Sebastian; Bjerg, Poul L.
2016-04-01
Ecosystem dynamics (e.g. temperature, inorganic nutrients) and properties (e.g. resilience, robustness), and ecological functions and services depend on the structure and diversity of biological communities, and the fluxes of energy and materials occurring within and across abiotic and biotic boundaries. The close interchange, i.e. multiple feedback loops, between hydrologic and biologic controls is also becoming increasingly evident. Holistic approaches are thus necessary for a robust understanding of ecosystem functioning and subsequent implementation of effective management practices across multiple spatial scales. Groundwater and surface water resources are under pressure from increasing global exploitation and anthropogenic impacts such as contamination by chemicals, leading to a severe degradation of essential ecological functions. Many of the environmental problems we face today have existed for decades; what has changed is our understanding of the key drivers, processes and impacts. The first reporting by European Member States (MS) on the status of their water bodies found that rivers and transitional waters were often in worse condition than lakes and coastal waters. This is not surprising considering that streams integrate all of the diverse stressors found within a catchment (e.g. contaminated sites; diffuse source pollution; water abstraction). The chemical status of a water body is relatively straightforward to assess, defined partly by environmental quality standards on priority substances and partly by additional regulations imposed by individual MS. However, the biological quality elements used for the classification of ecological status are only loosely defined, leaving MS free to develop their own assessment tools. Although useful for the individual MS, it impedes methodological standardization across different ecoregions, thus contributing to inconsistencies and data gaps across Europe. Moreover, despite the unambiguous importance of benthic habitats for overall ecosystem health, many biological indices tend only to reflect the ecological quality of surface water, rather than of the sedimentary zones where the accumulation of pollutants is often highest. To address this issue, we monitored meiobenthic (i.e. nematodes) and macrobenthic invertebrate communities along a pollution gradient in order to assess the impact of multiple stressors on a groundwater-fed stream, and thus quantify the link between chemical and ecological status. The studied stressors included point source pollutants originating from contaminated groundwater and aquaculture, and diffuse source pollutants originating from conventional agriculture and urban areas. The use of macrofauna is now well-accepted for assessing ecological integrity in aquatic ecosystems, but less is known about the application of meiofaunal community indicators. High abundance and ubiquitous distribution are two potential advantages for including meiofaunal indicators, and notably - for the case of groundwater-surface water interactions - they are particularly suitable for identifying changes in environmental conditions over smaller spatial scales. The results indicate a change in community composition for both meio- and macrobenthic fauna, pointing towards the presence of a local impact resulting from the discharging contaminated groundwater, which extends downstream along a dilution gradient of the groundwater contaminants. Ecological impacts could be linked to xenobiotic compounds coming from groundwater (both chlorinated solvents and pharmaceuticals), as well as the presence of trace metals of diffuse and/or biogenic origin.
NASA Astrophysics Data System (ADS)
Busnardo, Enrico; Ravagnan, Riccardo; Castellarin, Nicola; Canella, Claudio; Gandolfo, Luca; Petrillo, Giovanni
2017-04-01
Public opinion consider landfills as a problematic waste disposal system. They are perceived as groundwater and air source of pollution, and unfortunately it is true. For this reason, Regional Environmental Agencies (ARPA) need data in order to figure out the potential pollution near landfills. Remotely Piloted Aircraft Systems (RPAS) with specific sensors, could be a better solution than traditional terrestrial sensors. They provide a better sampling at different altitudes. Therefore, a 3D diffusion gas model could be improved. This study case is about a solid urban waste landfill, located on the Venetian Po Plain in the south of the Veneto Region. The "electronic nose" on the RPAS, needs to be stand still at least 15 seconds while sampling. For this reason, in this study case a multicopter RPAS was used. The result was a 3D concentration map of pollutant gases. The map was related with meteorological data from a Regional meteorological station located near the landfill to identify the gas source. In the end, the study about the olfactory impact was made using the OdiGauss model, developed by the Agricultural and Environmental Sciences Department of Udine University. It was also compared with a simulation carried out with CALWin software.
Yamamoto, F Y; Pereira, M V M; Lottermann, E; Santos, G S; Stremel, T R O; Doria, H B; Gusso-Choueri, P; Campos, S X; Ortolani-Machado, C F; Cestari, M M; Neto, F Filipak; Azevedo, J C R; Ribeiro, C A Oliveira
2016-09-01
The Iguaçu River, located at the Southern part of Brazil, has a great socioeconomic and environmental importance due to its high endemic fish fauna and its potential to generate hydroelectric power. However, Iguaçu River suffers intense discharge of pollutants in the origin of the river. In a previous report, the local environmental agency described water quality to improve along the river course. However, no study with integrated evaluation of chemical analysis and biological responses has been reported so far for the Iguaçu River. In the current study, three different Brazilian fish species (Astyanax bifasciatus, Chrenicicla iguassuensis, and Geophagus brasiliensis) were captured in the five cascading reservoirs of Iguaçu River for a multi-biomarker study. Chemical analysis in water, sediment, and muscle indicated high levels of bioavailable metals in all reservoirs. Polycyclic aromatic hydrocarbons (PAHs) were detected in the bile of the three fish species. Integration of the data through a FA/PCA analysis demonstrated the poorest environmental quality of the reservoir farthest from river's source, which is the opposite of what has been reported by the environmental agency. The presence of hazardous chemicals in the five reservoirs of Iguaçu River, their bioaccumulation in the muscle of fish, and the biological responses showed the impacts of human activities to this area and did not confirm a gradient of pollution between the five reservoirs, from the source toward Iguaçu River's mouth. Therefore, diffuse source of pollutants present along the river course are increasing the risk of exposure to biota and human populations.
Dutch approach to abating agricultural non-point pollution: farmers' behaviour and their motivation.
Sloots, K; Spierenburg, P; van der Vlies, A W
2004-01-01
In The Netherlands, agricultural activities are one of the major diffuse sources of nutrients and crop protection chemicals. A national legal and regulatory framework has been developed to combat the environmental burden from the agricultural industry. This resulted in the implementation of a government decree (AMvB) in the year 2000. Under pressure from NGOs, the Hollandse Eilanden en Waarden Water Board worked on a regional regulation in advance of this national legislation. ZHEW followed an approach of research, communication and partnering prior to implementing the national decree. The most important result of the chosen approach is that compliance with one of the most important measures, the crop-free zone, is close to 100%. There has been little improvement in the amount of pesticides in the open waters. Both water board and farmers are positive about the approach followed. Monitoring and evaluation proved to be essential when communicating with the agricultural sector. The results of attempts to influence behaviour must be recorded in order maintain the motivation to change behaviour. Information on the effects of the approach adopted to combating diffuse agricultural sources is gathered from a number of sources.
Detection of Pollution Caused by Solid Wastes
NASA Technical Reports Server (NTRS)
Golueke, Clarence G.
1971-01-01
To develop a means of detecting pollution, it s necessary to know something about the source and nature of the pollution. The type of pollution rising from solid wastes differs considerably from hat from liquid wastes or that from gaseous wastes ni its effect on the immediate environment. It may be "defined" by a series of negatives. When solid wastes are discarded on land, the resulting pollution is not land pollution in the sense of air and water pollution. For one thing, the solid wastes do not become a "part" of the land in that the wastes are neither intimately mixed nor homogenized into the land as are liquid and gaseous wastes into their respective media. The waste particles retain not only their chemical identity but also their visible (i.e., physical) characteristics. When buried, for example, the soil is under, above, and around the solids, because the wastes are there as discrete units. Secondly, solid wastes neither diffuse nor are they carried from the place at which they were deposited. In other words they remain stationary, providing of course the disposal site is land and not moving water. In a given area, solid wastes be not distributed uniformly over that area. Even the solid wastes falling into the specification of letter meets these specifications. In contrast liquid and gaseous wastes become intimately mixed, homogenized, and even dissolved in their media. Because solid wastes remain stationary, pollution constituted by their presence is highly localized and heavily concentrated, even to the extent that the pollution could be termed "micro" when compared to the macro-pollution arising from liquid and gasequs wastes.
Integrated climate-chemical indicators of diffuse pollution from land to water.
Mellander, Per-Erik; Jordan, Phil; Bechmann, Marianne; Fovet, Ophélie; Shore, Mairead M; McDonald, Noeleen T; Gascuel-Odoux, Chantal
2018-01-17
Management of agricultural diffuse pollution to water remains a challenge and is influenced by the complex interactions of rainfall-runoff pathways, soil and nutrient management, agricultural landscape heterogeneity and biogeochemical cycling in receiving water bodies. Amplified cycles of weather can also influence nutrient loss to water although they are less considered in policy reviews. Here, we present the development of climate-chemical indicators of diffuse pollution in highly monitored catchments in Western Europe. Specifically, we investigated the influences and relationships between weather processes amplified by the North Atlantic Oscillation during a sharp upward trend (2010-2016) and the patterns of diffuse nitrate and phosphorus pollution in rivers. On an annual scale, we found correlations between local catchment-scale nutrient concentrations in rivers and the influence of larger, oceanic-scale climate patterns defined by the intensity of the North Atlantic Oscillation. These influences were catchment-specific showing positive, negative or no correlation according to a typology. Upward trends in these decadal oscillations may override positive benefits of local management in some years or indicate greater benefits in other years. Developing integrated climate-chemical indicators into catchment monitoring indicators will provide a new and important contribution to water quality management objectives.
NASA Astrophysics Data System (ADS)
Bai, Yang; Wu, Lixin; Zhou, Yuan; Li, Ding
2017-04-01
Nitrogen oxides (NOX) and sulfur dioxide (SO2) emissions from coal combustion, which is oxidized quickly in the atmosphere resulting in secondary aerosol formation and acid deposition, are the main resource causing China's regional fog-haze pollution. Extensive literature has estimated quantitatively the lifetimes and emissions of NO2 and SO2 for large point sources such as coal-fired power plants and cities using satellite measurements. However, rare of these methods is suitable for sources located in a heterogeneously polluted background. In this work, we present a simplified emission effective radius extraction model for point source to study the NO2 and SO2 reduction trend in China with complex polluted sources. First, to find out the time range during which actual emissions could be derived from satellite observations, the spatial distribution characteristics of mean daily, monthly, seasonal and annual concentration of OMI NO2 and SO2 around a single power plant were analyzed and compared. Then, a 100 km × 100 km geographical grid with a 1 km step was established around the source and the mean concentration of all satellite pixels covered in each grid point is calculated by the area weight pixel-averaging approach. The emission effective radius is defined by the concentration gradient values near the power plant. Finally, the developed model is employed to investigate the characteristic and evolution of NO2 and SO2 emissions and verify the effectiveness of flue gas desulfurization (FGD) and selective catalytic reduction (SCR) devices applied in coal-fired power plants during the period of 10 years from 2006 to 2015. It can be observed that the the spatial distribution pattern of NO2 and SO2 concentration in the vicinity of large coal-burning source was not only affected by the emission of coal-burning itself, but also closely related to the process of pollutant transmission and diffusion caused by meteorological factors in different seasons. Our proposed model can be used to identify the effective operation time of FGD and SCR equipped in coal-fired power plant.
Tejeda-Agredano, Maria-Carmen; Mayer, Philipp; Ortega-Calvo, Jose-Julio
2014-01-01
Binding of polycyclic aromatic hydrocarbons (PAHs) to dissolved organic matter (DOM) can reduce the freely dissolved concentration, increase apparent solubility or enhance diffusive mass transfer. To study the effects of DOM on biodegradation, we used phenanthrene and pyrene as model PAHs, soil humic acids as model DOM and a soil Mycobacterium strain as a representative degrader organism. Humic acids enhanced the biodegradation of pyrene when present as solid crystals but not when initially dissolved or provided by partitioning from a polymer. Synchronous fluorescence spectrophotometry, scintillation counting and a microscale diffusion technique were applied in order to determine the kinetics of dissolution and diffusive mass transfer of pyrene. We suggest that humic acids can enhance or inhibit biodegradation as a result of the balance of two opposite effects, namely, solubilization of the chemicals on the one hand and inhibition of cell adhesion to the pollutant source on the other. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Tong, X. X.; Hu, B.; Xu, W. S.; Liu, J. G.; Zhang, P. C.
2017-12-01
In this paper, Three Gorges Reservoir Area (TGRA) was chosen to be the study area, the export coefficients of different land-use type were calculated through the observation experiments and literature consultation, and then the load of non-point source (NPS) nitrogen and phosphorus of different pollution sources such as farmland pollution sources, decentralized livestock and poultry breeding pollution sources and domestic pollution sources were estimated. The results show as follows: the pollution load of dry land is the main source of farmland pollution. The order of total nitrogen load of different pollution sources from high to low is livestock breeding pollution, domestic pollution, land use pollution, while the order of phosphorus load of different pollution sources from high to low is land use pollution, livestock breeding pollution, domestic pollution, Therefore, reasonable farmland management, effective control methods of dry land fertilization and sewage discharge of livestock breeding are the keys to the prevention and control of NPS nitrogen and phosphorus in TGRA.
Liu, Wei; Yang, Jian-jun; Wang, Jun; Wang, Guo; Cao, Yue-e
2016-05-15
The opencast mine of East Junggar Basin in Xinjiang is the largest self-contained coalfield in China, and the ecological environment of the opencast is very fragile because of its arid climate and poor soil. In this study, 50 soil samples (from 0 to 30 cm depth soil at intervals of 10 cm) in opencast Mine of East Junggar Basin in Xinjiang were collected in order to explore the heavy metals contamination of the coal mining. The contents of zinc (Zn), copper (Cu), cadmium (Cr), lead (Pb), mercury (Hg) and arsenic (As) were measured and the degree of pollution was assessed by Nemerow index, geo-accumulation (Igeo) index and potential ecological risk index. In addition, the layered comparison, dust fall and the distance between coal mine and samples location were used to analyze the source of heavy metals contamination. The results showed that value of As surpassed the Chinese soil quality standard class I (GB 15618-1995) mostly severely, followed by Cr, a relatively lower surpass was obtained by Hg and Cu, while Zn and Pb did not surpass the standard. According to the standard, the soil heavy metals content of research region was in light pollution status and the pollution index for each heavy metal followed the order of As (2.07) > Cr (0.95) > Cu (0.55) > Zn (0.48) > Hg (0.45) > Pb (0.38), which demonstrated a heavy pollution of As and clean status of others. Additionally, an Igeo value of 1.14 for Hg reflected a moderated pollution. The major contribution factor was Hg with a risk index of 251.40. The source analysis showed that the content of Pb in the surface soil (10-20 cm) was different from that in the deep layer (20-30 cm), which may be caused by coal combustion and other human activities. The sources of Hg and As were similar and may come from coal combustion. The distance to the mining area was not the major factor affecting the diffusion of heavy metals, other candidate factors included terrain, aspect and wind direction, etc.
[Observation on atmospheric pollution in Xianghe during Beijing 2008 Olympic Games].
Pan, Yue-Peng; Wang, Yue-Si; Hu, Bo; Liu, Quan; Wang, Ying-Hong; Nan, Wei-Dong
2010-01-01
There is a concern that much of the atmospheric pollution experienced in Beijing is regional in nature and not attributable to local sources. The objective of this study is to examine the contribution of sources outside Beijing to atmospheric pollution levels during Beijing 2008 Olympic Games. The observations of SO2, NO(x), O3, PM2.5 and PM10 were conducted from June 1 to September 30, 2008 in Xianghe, a rural site about 70 km southeast of Beijing. Sources and transportation of atmospheric pollution during the experiment were discussed with surface meteorology data and backward trajectories calculated using HYSPLIT model. The results showed that the daily average maximum (mean +/- standard deviation) concentrations of SO2, NO(x), O3, PM2.5, and PM10 during observation reached 84.4(13.4 +/- 15.2), 43.3 (15.9 +/- 9.1), 230 (82 +/- 38), 184 (76 +/- 42) and 248 (113 +/- 52) microg x m(-3), respectively. In particular, during the pollution episodes from July 20 to August 12, the hourly average concentration of O3 exceeded the National Ambient Air Quality Standard II for 46 h (9%), and the daily average concentration of PM10 exceeded the Standard for 11 d (46%); PM2.5 exceeded the US EPA Standard for 18 d (75%). The daily average concentrations of SO2, NO(x), O3, PM2.5 and PM10 decreased from 27.7, 18.6, 96, 90, 127 microg x m(-3) in June-July to 5.8, 13.2, 80, 60, 106 microg x m(-3) during Olympic Games (August-September), respectively. The typical diurnal variations of NO(x), PM2.5 and PM10 were similar, peaking at 07:00 and 20:00, while the maximum of O3 occurred between 14:00 to 16:00 local time. The findings also suggested that the atmospheric pollution in Xianghe is related to local emission, regional transport as well as the meteorological conditions. Northerly wind and precipitation are favorable for diffusion and wet deposition of pollutants, while sustained south flows make the atmospheric pollution more serious. The lead-lag correlation analysis during the pollution episodes from July 20 to August 12 showed that there are about 6-10 h (0.57 < r < 0.65, p = 0.01) of hourly average PM2.5 in Beijing lagging Xianghe, reaching the maximum at 8 h, which indicates that the real-time atmospheric PM2.5 database of Xianghe might provides early warning for the Beijing PM2.5 pollution events.
Karapanagioti, H K; Endo, S; Ogata, Y; Takada, H
2011-02-01
Plastic pellets found stranded on beaches are hydrophobic organic materials and thus, they are a favourable medium for persistent organic pollutants to absorb to. In the present study, plastic pellets are used to determine the diffuse pollution of selected Greek beaches. Samples of pellets were taken from these beaches and were analyzed for PCBs, DDTs, HCHs, and PAHs. The observed differences among pellets from various sampling sites are related to the pollution occurring at each site. Plastic pellets collected in Saronikos Gulf beaches demonstrate much higher pollutant loading than the ones collected in a remote island or close to an agricultural area. Based on data collected in this study and the International Pellet Watch program, pollution in Saronikos Gulf, Greece, is comparable to other heavily industrialized places of the world. The present study demonstrates the potential of pellet watch to be utilized as a detailed-scale monitoring tool within a single country. Copyright © 2010 Elsevier Ltd. All rights reserved.
[A landscape ecological approach for urban non-point source pollution control].
Guo, Qinghai; Ma, Keming; Zhao, Jingzhu; Yang, Liu; Yin, Chengqing
2005-05-01
Urban non-point source pollution is a new problem appeared with the speeding development of urbanization. The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution, and more difficult to control. Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution, mainly adopting local repairing practices to control the pollutants in surface runoff. Because of the close relationship between urban land use patterns and non-point source pollution, it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution, which needs, firstly, analyzing and evaluating the influence of landscape structure on water-bodies, pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields, and secondly, adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern, and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liverman, James L.
Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant. (LK)
Groundwater vulnerability and risk mapping using GIS, modeling and a fuzzy logic tool.
Nobre, R C M; Rotunno Filho, O C; Mansur, W J; Nobre, M M M; Cosenza, C A N
2007-12-07
A groundwater vulnerability and risk mapping assessment, based on a source-pathway-receptor approach, is presented for an urban coastal aquifer in northeastern Brazil. A modified version of the DRASTIC methodology was used to map the intrinsic and specific groundwater vulnerability of a 292 km(2) study area. A fuzzy hierarchy methodology was adopted to evaluate the potential contaminant source index, including diffuse and point sources. Numerical modeling was performed for delineation of well capture zones, using MODFLOW and MODPATH. The integration of these elements provided the mechanism to assess groundwater pollution risks and identify areas that must be prioritized in terms of groundwater monitoring and restriction on use. A groundwater quality index based on nitrate and chloride concentrations was calculated, which had a positive correlation with the specific vulnerability index.
A study of atmospheric diffusion from the LANDSAT imagery. [pollution transport over the ocean
NASA Technical Reports Server (NTRS)
Dejesusparada, N. (Principal Investigator); Viswanadham, Y.; Torsani, J. A.
1981-01-01
LANDSAT multispectral scanner data of the smoke plumes which originated in eastern Cabo Frio, Brazil and crossed over into the Atlantic Ocean, are analyzed to illustrate how high resolution LANDSAT imagery can aid meteorologists in evaluating specific air pollution events. The eleven LANDSAT images selected are for different months and years. The results show that diffusion is governed primarily by water and air temperature differences. With colder water, low level air is very stable and the vertical diffusion is minimal; but water warmer than the air induces vigorous diffusion. The applicability of three empirical methods for determining the horizontal eddy diffusivity coefficient in the Gaussian plume formula was evaluated with the estimated standard deviation of the crosswind distribution of material in the plume from the LANDSAT imagery. The vertical diffusion coefficient in stable conditions is estimated using Weinstock's formulation. These results form a data base for use in the development and validation of meso scale atmospheric diffusion models.
Stadler, H; Klock, E; Skritek, P; Mach, R L; Zerobin, W; Farnleitner, A H
2010-01-01
Because spring water quality from alpine karst aquifers can change very rapidly during event situations, water abstraction management has to be performed in near real-time. Four summer events (2005-2008) at alpine karst springs were investigated in detail in order to evaluate the spectral absorption coefficient at 254 nm (SAC254) as a real-time early warning proxy for faecal pollution. For the investigation Low-Earth-Orbit (LEO) Satellite-based data communication between portable hydrometeorological measuring stations and an automated microbiological sampling device was used. The method for event triggered microbial sampling and analyzing was already established and described in a previous paper. Data analysis including on-line event characterisation (i.e. precipitation, discharge, turbidity, SAC254) and comprehensive E. coli determination (n>800) indicated that SAC254 is a useful early warning proxy. Irrespective of the studied event situations SAC254 always increased 3 to 6 hours earlier than the onset of faecal pollution, featuring different correlation phases. Furthermore, it seems also possible to use SAC254 as a real-time proxy parameter for estimating the extent of faecal pollution after establishing specific spring and event-type calibrations that take into consideration the variability of the occurrence and the transferability of faecal material It should be highlighted that diffuse faecal pollution from wildlife and live stock sources was responsible for spring water contamination at the investigated catchments. In this respect, the SAC254 can also provide useful information to support microbial source tracking efforts where different situations of infiltration have to be investigated.
Bao, Zhongwen; Haberer, Christina M; Maier, Uli; Beckingham, Barbara; Amos, Richard T; Grathwohl, Peter
2016-11-01
Temperature changes can drive cycling of semi-volatile pollutants between different environmental compartments (e.g. atmosphere, soil, plants). To evaluate the impact of daily temperature changes on atmospheric concentration fluctuations we employed a physically based model coupling soil, plants and the atmosphere, which accounts for heat transport, effective gas diffusion, sorption and biodegradation in the soil as well as eddy diffusion and photochemical oxidation in the atmospheric boundary layer of varying heights. The model results suggest that temperature-driven re-volatilization and uptake in soils cannot fully explain significant diurnal concentration fluctuations of atmospheric pollutants as for example observed for polychlorinated biphenyls (PCBs). This holds even for relatively low water contents (high gas diffusivity) and high sorption capacity of the topsoil (high organic carbon content and high pollutant concentration in the topsoil). Observed concentration fluctuations, however, can be easily matched if a rapidly-exchanging environmental compartment, such as a plant layer, is introduced. At elevated temperatures, plants release organic pollutants, which are rapidly distributed in the atmosphere by eddy diffusion. For photosensitive compounds, e.g. some polycyclic aromatic hydrocarbons (PAHs), decreasing atmospheric concentrations would be expected during daytime for the bare soil scenario. This decline is buffered by a plant layer, which acts as a ground-level reservoir. The modeling results emphasize the importance of a rapidly-exchanging compartment above ground to explain short-term atmospheric concentration fluctuations. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Delhotal, Katherine Casey
Landfill gas (LFG) projects use the gas created from decomposing waste, which is approximately 49% methane, and substitute it for natural gas in engines, boilers, turbines, and other technologies to produce energy or heat. The projects are beneficial in terms of increased safety at the landfill, production of a cost-effective source of energy or heat, reduced odor, reduced air pollution emissions, and reduced greenhouse gas emissions. However, landfills sometimes face conflicting policy incentives. The theory of technical change shows that the diffusion of a technology or groups of technologies increases slowly in the beginning and then picks up speed as knowledge and better understanding of using the technology diffuses among potential users. Using duration analysis, data on energy prices, State and Federal policies related to landfill gas, renewable energy, and air pollution, as well as control data on landfill characteristics, I estimate the influence and direction of influence of renewable portfolio standards (RPS). The analysis found that RPS positively influences the diffusion of landfill gas technologies, encouraging landfills to consider electricity generation projects over direct sales of LFG to another facility. Energy price increases or increased revenues for a project are also critical. Barriers to diffusion include air emission permits in non-attainment areas and policies, such as net metering, which promote other renewables over LFG projects. Using the estimates from the diffusion equations, I analyze the potential influence of a Federal RPS as well as the potential interaction with a Federal, market based climate change policy, which will increase the revenue of a project through higher energy sale prices. My analysis shows that a market based climate change policy such as a cap-and-trade or carbon tax scheme would increase the number of landfill gas projects significantly more than a Federal RPS.
Krall, Jenna R; Ladva, Chandresh N; Russell, Armistead G; Golan, Rachel; Peng, Xing; Shi, Guoliang; Greenwald, Roby; Raysoni, Amit U; Waller, Lance A; Sarnat, Jeremy A
2018-06-01
Concentrations of traffic-related air pollutants are frequently higher within commuting vehicles than in ambient air. Pollutants found within vehicles may include those generated by tailpipe exhaust, brake wear, and road dust sources, as well as pollutants from in-cabin sources. Source-specific pollution, compared to total pollution, may represent regulation targets that can better protect human health. We estimated source-specific pollution exposures and corresponding pulmonary response in a panel study of commuters. We used constrained positive matrix factorization to estimate source-specific pollution factors and, subsequently, mixed effects models to estimate associations between source-specific pollution and pulmonary response. We identified four pollution factors that we named: crustal, primary tailpipe traffic, non-tailpipe traffic, and secondary. Among asthmatic subjects (N = 48), interquartile range increases in crustal and secondary pollution were associated with changes in lung function of -1.33% (95% confidence interval (CI): -2.45, -0.22) and -2.19% (95% CI: -3.46, -0.92) relative to baseline, respectively. Among non-asthmatic subjects (N = 51), non-tailpipe pollution was associated with pulmonary response only at 2.5 h post-commute. We found no significant associations between pulmonary response and primary tailpipe pollution. Health effects associated with traffic-related pollution may vary by source, and therefore some traffic pollution sources may require targeted interventions to protect health.
Calderón-Garcidueñas, Lilian; Torres-Jardón, Ricardo; Kulesza, Randy J; Park, Su-Bin; D'Angiulli, Amedeo
2014-01-01
Millions of children in polluted cities are showing brain detrimental effects. Urban children exhibit brain structural and volumetric abnormalities, systemic inflammation, olfactory, auditory, vestibular and cognitive deficits v low-pollution controls. Neuroinflammation and blood-brain-barrier (BBB) breakdown target the olfactory bulb, prefrontal cortex and brainstem, but are diffusely present throughout the brain. Urban adolescent Apolipoprotein E4 carriers significantly accelerate Alzheimer pathology. Neurocognitive effects of air pollution are substantial, apparent across all populations, and potentially clinically relevant as early evidence of evolving neurodegenerative changes. The diffuse nature of the neuroinflammation and neurodegeneration forces to employ a weight of evidence approach incorporating current clinical, cognitive, neurophysiological, radiological and epidemiological research. Pediatric air pollution research requires extensive multidisciplinary collaborations to accomplish a critical goal: to protect exposed children through multidimensional interventions having both broad impact and reach. Protecting children and teens from neural effects of air pollution should be of pressing importance for public health.
Calderón-Garcidueñas, Lilian; Torres-Jardón, Ricardo; Kulesza, Randy J.; Park, Su-Bin; D’Angiulli, Amedeo
2014-01-01
Millions of children in polluted cities are showing brain detrimental effects. Urban children exhibit brain structural and volumetric abnormalities, systemic inflammation, olfactory, auditory, vestibular and cognitive deficits v low-pollution controls. Neuroinflammation and blood-brain-barrier (BBB) breakdown target the olfactory bulb, prefrontal cortex and brainstem, but are diffusely present throughout the brain. Urban adolescent Apolipoprotein E4 carriers significantly accelerate Alzheimer pathology. Neurocognitive effects of air pollution are substantial, apparent across all populations, and potentially clinically relevant as early evidence of evolving neurodegenerative changes. The diffuse nature of the neuroinflammation and neurodegeneration forces to employ a weight of evidence approach incorporating current clinical, cognitive, neurophysiological, radiological and epidemiological research. Pediatric air pollution research requires extensive multidisciplinary collaborations to accomplish a critical goal: to protect exposed children through multidimensional interventions having both broad impact and reach. Protecting children and teens from neural effects of air pollution should be of pressing importance for public health. PMID:25161617
NASA Astrophysics Data System (ADS)
Velasco, Erik; Siegmann, Philip; Siegmann, Hans C.
2004-09-01
Several studies regarding particulate matter in air pollution have been performed in Mexico City, but none have focused on environment exposure to particle-bound polycyclic aromatic hydrocarbons (PPAH), which are related to the occurrence of cardiopulmonary diseases and mortality. On this account, this study presents measurements of personal exposure to PPAH in different outdoor and indoor environments, as well as along roadways in Mexico City. The measurements were done with portable sensors based on photoelectric charging and diffusion charging to determine the PPAH concentrations and the joint active surface of all particles, respectively. The use of these two sensors in parallel is a useful tool to qualitatively identify the major sources and to describe the physical and chemical characteristics of the particles. The highest exposures were found in ambient air near traffic sources, mainly at sites with great influence of diesel vehicles, such as urban transfer bus stations. Roadway measurements showed that Mexican PPAH pollution levels are between those in large cities in Europe and USA. For indoor environments such as residences, shopping centers, restaurants and hospitality venues, it was found that secondhand smoke is the major contributor, however badly calibrated pilot stoves, inefficient ventilation and faulty air-conditioning systems can be additional sources of PPAH.
Wind-Tunnel Modeling of Flow Diffusion over an Urban Complex.
URBAN AREAS, *ATMOSPHERIC MOTION, *AIR POLLUTION, ATMOSPHERIC MOTION, WIND TUNNEL MODELS, HEAT, DIFFUSION , TURBULENT BOUNDARY LAYER, WIND, SKIN FRICTION, MATHEMATICAL MODELS, URBAN PLANNING, INDIANA.
Boskidis, Ioannis; Gikas, Georgios D; Pisinaras, Vassilios; Tsihrintzis, Vassilios A
2010-09-01
The results of an investigation of the quantitative and qualitative characteristics of Vosvozis river in Northern Greece is presented. For the purposes of this study, three gaging stations were installed along Vosvozis river, where water quantity and quality measurements were conducted for the period August 2005 to November 2006. Water discharge, temperature, pH, dissolved oxygen (DO) and electrical conductivity (EC) were measured in situ using appropriate equipment. The collected water samples were analyzed in the laboratory for the determination of nitrate, nitrite and ammonium nitrogen, total Kjeldalh nitrogen (TKN), orthophosphate (OP), total phosphorus (TP), COD, and BOD. Agricultural diffuse sources provided the major source of nitrate nitrogen loads during the wet period. During the dry period (from June to October), the major nutrient (N, P) and COD, BOD sources were point sources. The trophic status of Vosvozis river during the monitoring period was determined as eutrophic, based on Dodds classification scheme. Moreover, the SWAT model was used to simulate hydrographs and nutrient loads. SWAT was validated with the measured data. Predicted hydrographs and pollutographs were plotted against observed values and showed good agreement. The validated model was used to test eight alternative scenarios concerning different cropping management approaches. The results of these scenarios indicate that nonpoint source pollution is the prevailing type of pollution in the study area. The SWAT model was found to satisfactorily simulate processes in ephemeral river basins and is an effective tool in water resources management.
Zhou, Liang; Xu, Jian-Gang; Sun, Dong-Qi; Ni, Tian-Hua
2013-02-01
Agricultural non-point source pollution is of importance in river deterioration. Thus identifying and concentrated controlling the key source-areas are the most effective approaches for non-point source pollution control. This study adopts inventory method to analysis four kinds of pollution sources and their emissions intensity of the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in 173 counties (cities, districts) in Huaihe River Basin. The four pollution sources include livestock breeding, rural life, farmland cultivation, aquacultures. The paper mainly addresses identification of non-point polluted sensitivity areas, key pollution sources and its spatial distribution characteristics through cluster, sensitivity evaluation and spatial analysis. A geographic information system (GIS) and SPSS were used to carry out this study. The results show that: the COD, TN and TP emissions of agricultural non-point sources were 206.74 x 10(4) t, 66.49 x 10(4) t, 8.74 x 10(4) t separately in Huaihe River Basin in 2009; the emission intensity were 7.69, 2.47, 0.32 t.hm-2; the proportions of COD, TN, TP emissions were 73%, 24%, 3%. The paper achieves that: the major pollution source of COD, TN and TP was livestock breeding and rural life; the sensitivity areas and priority pollution control areas among the river basin of non-point source pollution are some sub-basins of the upper branches in Huaihe River, such as Shahe River, Yinghe River, Beiru River, Jialu River and Qingyi River; livestock breeding is the key pollution source in the priority pollution control areas. Finally, the paper concludes that pollution type of rural life has the highest pollution contribution rate, while comprehensive pollution is one type which is hard to control.
[Groundwater organic pollution source identification technology system research and application].
Wang, Xiao-Hong; Wei, Jia-Hua; Cheng, Zhi-Neng; Liu, Pei-Bin; Ji, Yi-Qun; Zhang, Gan
2013-02-01
Groundwater organic pollutions are found in large amount of locations, and the pollutions are widely spread once onset; which is hard to identify and control. The key process to control and govern groundwater pollution is how to control the sources of pollution and reduce the danger to groundwater. This paper introduced typical contaminated sites as an example; then carried out the source identification studies and established groundwater organic pollution source identification system, finally applied the system to the identification of typical contaminated sites. First, grasp the basis of the contaminated sites of geological and hydrogeological conditions; determine the contaminated sites characteristics of pollutants as carbon tetrachloride, from the large numbers of groundwater analysis and test data; then find the solute transport model of contaminated sites and compound-specific isotope techniques. At last, through groundwater solute transport model and compound-specific isotope technology, determine the distribution of the typical site of organic sources of pollution and pollution status; invest identified potential sources of pollution and sample the soil to analysis. It turns out that the results of two identified historical pollution sources and pollutant concentration distribution are reliable. The results provided the basis for treatment of groundwater pollution.
Performance of pond-wetland complexes as a preliminary processor of drinking water sources.
Wang, Weidong; Zheng, Jun; Wang, Zhongqiong; Zhang, Rongbin; Chen, Qinghua; Yu, Xinfeng; Yin, Chengqing
2016-01-01
Shijiuyang Constructed Wetland (110 hm(2)) is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water in the Xincheng River every day and supplies raw water for Shijiuyang Drinking Water Plant. Daily data for 28 months indicated that the major water quality indexes of source water had been improved by one grade. The percentage increase for dissolved oxygen and the removal rates of ammonia nitrogen, iron and manganese were 73.63%, 38.86%, 35.64%, and 22.14% respectively. The treatment performance weight of ponds and plant-bed/ditch systems was roughly equal but they treated different pollutants preferentially. Most water quality indexes had better treatment efficacy with increasing temperature and inlet concentrations. These results revealed that the pond-wetland complexes exhibited strong buffering capacity for source water quality improvement. The treatment cost of Shijiuyang Drinking Water Plant was reduced by about 30.3%. Regional rainfall significantly determined the external river water levels and adversely deteriorated the inlet water quality, thus suggesting that the "hidden" diffuse pollution in the multitudinous stream branches as well as their catchments should be the controlling emphases for river source water protection in the future. The combination of pond and plant-bed/ditch systems provides a successful paradigm for drinking water source pretreatment. Three other drinking water source treatment wetlands with ponds and plant-bed/ditch systems are in operation or construction in the stream networks of the Yangtze River Delta and more people will be benefited. Copyright © 2015. Published by Elsevier B.V.
Vymazal, Jan; Březinová, Tereza
2015-02-01
Pesticides are used in modern agriculture to increase crop yields, but they may pose a serious threat to aquatic ecosystems. Pesticides may enter water bodies through diffuse and point sources, but diffuse sources are probably the most important. Among diffuse pollution, surface runoff and erosion, leaching and drainage represent the major pathways. The most commonly used mitigation techniques to prevent pesticide input into water bodies include edge-of-field and riparian buffer strips, vegetated ditches and constructed wetlands. The first attempts to use wetland macrophytes for pesticide removal were carried out as early as the 1970s, but only in the last decade have constructed wetlands for pesticide mitigation become widespread. The paper summarizes 47 studies in which removal of 87 pesticides was monitored. The survey revealed that constructed wetlands with free water surface are the most commonly used type. Also, it has been identified that removal of pesticides is highly variable. The results of the survey revealed that the highest pesticide removal was achieved for pesticides of the organochlorine, strobilurin/strobin, organosphosphate and pyrethroid groups while the lowest removals were observed for pesticides of the triazinone, aryloxyalkanoic acid and urea groups. The removal of pesticides generally increases with increasing value of KOC but the relationship is not strong. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhu, Lei; Song, JinXi; Liu, WanQing
2017-12-01
Huaxian Section is the last hydrological and water quality monitoring section of Weihe River Watershed. Weihe River Watershed above Huaxian Section is taken as the research objective in this paper and COD is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads—characteristic section load(CSLD) method is suggested and point source pollution and non-point source pollution loads of Weihe River Watershed above Huaxian Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Huaxian Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above Huaxian Section change greatly and the non-point source pollution load proportions of total pollution load of COD decrease in the normal, rainy and wet period in turn.
Calculating NH3-N pollution load of wei river watershed above Huaxian section using CSLD method
NASA Astrophysics Data System (ADS)
Zhu, Lei; Song, JinXi; Liu, WanQing
2018-02-01
Huaxian Section is the last hydrological and water quality monitoring section of Weihe River Watershed. So it is taken as the research objective in this paper and NH3-N is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads—characteristic section load (CSLD)method is suggested and point source pollution and non-point source pollution loads of Weihe River Watershed above Huaxian Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Huaxian Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above Huaxian Section change greatly. The non-point source pollution load proportions of total pollution load of NH3-N decrease in the normal, rainy and wet period in turn.
Genetic Diversity of Escherichia coli Isolated from Urban Rivers and Beach Water
McLellan, Sandra L.
2004-01-01
Repetitive element anchored PCR was used to evaluate the genetic profiles of Escherichia coli isolated from surface water contaminated with urban stormwater, sanitary sewage, and gull feces to determine if strains found in environmental samples reflect the strain composition of E. coli obtained from host sources. Overall, there was less diversity in isolates collected from river and beach sites than with isolates obtained from human and nonhuman sources. Unique strain types comprised 28.8, 29.2, and 15.0% of the isolate data sets recovered from stormwater, river water, and beach water, respectively. In contrast, 50.4% of gull isolates and 41.2% of sewage isolates were unique strain types. River water, which is expected to contain E. coli strains from many diffuse sources of nonpoint source pollution, contained strains most closely associated with other river water isolates that were collected at different sites or on different days. However, river sites impacted by sewage discharge had approximately 20% more strains similar to sewage isolates than did sites impacted by stormwater alone. Beach sites with known gull fecal contamination contained E. coli most similar to other beach isolates rather than gull isolates collected at these same sites, indicating underrepresentation of possible gull strains. These results suggest large numbers of strains are needed to represent contributing host sources within a geographical location. Additionally, environmental survival may influence the composition of strains that can be recovered from contaminated waters. Understanding the ecology of indicator bacteria is important when interpreting fecal pollution assessments and developing source detection methodology. PMID:15294799
NASA Astrophysics Data System (ADS)
Fontaine, G.; Brassard, P.; Dufour, P.; Tremblay, P.-E.
2015-06-01
The accretion-diffusion picture is the model par excellence for describing the presence of planetary debris polluting the atmospheres of relatively cool white dwarfs. Some important insights into the process may be derived using an approximate approach which combines static stellar models with estimates of diffusion timescales at the base of the outer convection zone or, in its absence, at the photosphere. Until recently, and to our knowledge, values of diffusion timescales in white dwarfs have all been obtained on the basis of the same physics as that developed initially by Paquette et al., including their diffusion coefficients and thermal diffusion coefficients. In view of the recent exciting discoveries of a plethora of metals (including some never seen before) polluting the atmospheres of an increasing number of cool white dwarfs, we felt that a new look at the estimates of settling timescales would be worthwhile. We thus provide improved estimates of diffusion timescales for all 27 elements from Li to Cu in the periodic table in a wide range of the surface gravity-effective temperature domain and for both DA and non-DA stars.
Seidensticker, Sven; Zarfl, Christiane; Cirpka, Olaf A; Fellenberg, Greta; Grathwohl, Peter
2017-11-07
In aqueous environments, hydrophobic organic contaminants are often associated with particles. Besides natural particles, microplastics have raised public concern. The release of pollutants from such particles depends on mass transfer, either in an aqueous boundary layer or by intraparticle diffusion. Which of these mechanisms controls the mass-transfer kinetics depends on partition coefficients, particle size, boundary conditions, and time. We have developed a semianalytical model accounting for both processes and performed batch experiments on the desorption kinetics of typical wastewater pollutants (phenanthrene, tonalide, and benzophenone) at different dissolved-organic-matter concentrations, which change the overall partitioning between microplastics and water. Initially, mass transfer is externally dominated, while finally, intraparticle diffusion controls release kinetics. Under boundary conditions typical for batch experiments (finite bath), desorption accelerates with increasing partition coefficients for intraparticle diffusion, while it becomes independent of partition coefficients if film diffusion prevails. On the contrary, under field conditions (infinite bath), the pollutant release controlled by intraparticle diffusion is not affected by partitioning of the compound while external mass transfer slows down with increasing sorption. Our results clearly demonstrate that sorption/desorption time scales observed in batch experiments may not be transferred to field conditions without an appropriate model accounting for both the mass-transfer mechanisms and the specific boundary conditions at hand.
EFFECTS OF WIND SHEAR ON POLLUTION DISPERSION. (R827929)
Using an accurate numerical method for simulating the advection and diffusion of pollution puffs, it is demonstrated that point releases of pollution grow into a shape reflecting the vertical wind shear profile experienced by the puff within a time scale less than 4 h. Fo...
ERIC Educational Resources Information Center
Scorer, Richard S.
The purpose of this book is to describe the basic mechanisms whereby pollution is transported and diffused in the atmosphere. It is designed to give practitioners an understanding of basic mechanics and physics so they may have a correct basis on which to formulate their decisions related to practical air pollution control problems. Since many…
Mockler, Eva M; Deakin, Jenny; Archbold, Marie; Gill, Laurence; Daly, Donal; Bruen, Michael
2017-12-01
More than half of surface water bodies in Europe are at less than good ecological status according to Water Framework Directive assessments, and diffuse pollution from agriculture remains a major, but not the only, cause of this poor performance. Agri-environmental policy and land management practices have, in many areas, reduced nutrient emissions to water. However, additional measures may be required in Ireland to further decouple the relationship between agricultural productivity and emissions to water, which is of vital importance given on-going agricultural intensification. The Source Load Apportionment Model (SLAM) framework characterises sources of phosphorus (P) and nitrogen (N) emissions to water at a range of scales from sub-catchment to national. The SLAM synthesises land use and physical characteristics to predict emissions from point (wastewater, industry discharges and septic tank systems) and diffuse sources (agriculture, forestry, etc.). The predicted annual nutrient emissions were assessed against monitoring data for 16 major river catchments covering 50% of the area of Ireland. At national scale, results indicate that total average annual emissions to surface water in Ireland are over 2700tyr -1 of P and 82,000tyr -1 of N. The proportional contributions from individual sources show that the main sources of P are from municipal wastewater treatment plants and agriculture, with wide variations across the country related to local anthropogenic pressures and the hydrogeological setting. Agriculture is the main source of N emissions to water across all regions of Ireland. These policy-relevant results synthesised large amounts of information in order to identify the dominant sources of nutrients at regional and local scales, contributing to the national nutrient risk assessment of Irish water bodies. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhou, Jiabin; Xing, Zhenyu; Deng, Junjun; Du, Ke
2016-06-01
During the past decade, huge research resources have been devoted into studies of air pollution in China, which generated abundant datasets on emissions and pollution characterization. Due to the complex nature of air pollution as well as the limitations of each individual investigating approach, the published results were sometimes perplexing and even contradicting. This research adopted a multi-method approach to investigate region-specific air pollution characteristics and sources in China, results obtained using different analytical and receptor modeling methods were inter-compared for validation and interpretation. A year-round campaign was completed for comprehensive characterization of PM2.5 over four key emission regions: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). Atmospheric PM2.5 samples were collected from 10/2012 to 08/2013 at four regional sites, located on the diffusion paths of air masses from their corresponding megacities (i.e., Beijing, Shanghai, Guangzhou, and Chengdu). The annual average PM2.5 mass concentrations showed distinct regional difference, with the highest observed at BTH and lowest at PRD site. Nine water-soluble ions together contributed 33-41% of PM2.5 mass, with three dominant ionic species being SO42-, NO3-, NH4+, and carbonaceous particulate matter contributed 16-23% of PM2.5 mass. This implied that combustion and secondary formation were the main sources for PM2.5 in China. In addition, SO42-, NO3-, NH4+, and carbonaceous components (OC, EC) showed clear seasonal patterns with the highest concentration occurring in winter while the lowest in summer. Principal component analysis performed on aerosol data revealed that vehicular emissions, coal/biomass combustion, industry source, soil dust as well as secondary formation were the main potential sources for the ionic components of PM2.5. The characteristic chemical species combined with back trajectory analysis indicated that BTH was heavily influenced by air masses originating from Mongolia and North China Plain regions, whereas SB suffered from both local emissions of Sichuan Basin and biomass burning via long-range transport from South Asia. Sourcing conclusions from this study will be compared, validated and interpreted with those obtained using organic molecular marker and carbon isotope analyses to be presented parts II and III of this series.
Source influence on emission pathways and ambient PM2.5 pollution over India (2015-2050)
NASA Astrophysics Data System (ADS)
Venkataraman, Chandra; Brauer, Michael; Tibrewal, Kushal; Sadavarte, Pankaj; Ma, Qiao; Cohen, Aaron; Chaliyakunnel, Sreelekha; Frostad, Joseph; Klimont, Zbigniew; Martin, Randall V.; Millet, Dylan B.; Philip, Sajeev; Walker, Katherine; Wang, Shuxiao
2018-06-01
India is currently experiencing degraded air quality, and future economic development will lead to challenges for air quality management. Scenarios of sectoral emissions of fine particulate matter and its precursors were developed and evaluated for 2015-2050, under specific pathways of diffusion of cleaner and more energy-efficient technologies. The impacts of individual source sectors on PM2.5 concentrations were assessed through systematic simulations of spatially and temporally resolved particulate matter concentrations, using the GEOS-Chem model, followed by population-weighted aggregation to national and state levels. We find that PM2.5 pollution is a pan-India problem, with a regional character, and is not limited to urban areas or megacities. Under present-day emissions, levels in most states exceeded the national PM2.5 annual standard (40 µg m-3). Sources related to human activities were responsible for the largest proportion of the present-day population exposure to PM2.5 in India. About 60 % of India's mean population-weighted PM2.5 concentrations come from anthropogenic source sectors, while the remainder are from other
sources, windblown dust and extra-regional sources. Leading contributors are residential biomass combustion, power plant and industrial coal combustion and anthropogenic dust (including coal fly ash, fugitive road dust and waste burning). Transportation, brick production and distributed diesel were other contributors to PM2.5. Future evolution of emissions under regulations set at current levels and promulgated levels caused further deterioration of air quality in 2030 and 2050. Under an ambitious prospective policy scenario, promoting very large shifts away from traditional biomass technologies and coal-based electricity generation, significant reductions in PM2.5 levels are achievable in 2030 and 2050. Effective mitigation of future air pollution in India requires adoption of aggressive prospective regulation, currently not formulated, for a three-pronged switch away from (i) biomass-fuelled traditional technologies, (ii) industrial coal-burning and (iii) open burning of agricultural residue. Future air pollution is dominated by industrial process emissions, reflecting larger expansion in industrial, rather than residential energy demand. However, even under the most active reductions envisioned, the 2050 mean exposure, excluding any impact from windblown mineral dust, is estimated to be nearly 3 times higher than the WHO Air Quality Guideline.
Diffusion of organic pollutants within a biofilm in porous media
NASA Astrophysics Data System (ADS)
Fan, Chihhao; Kao, Chen-Fei; Liu, You-Hsi
2017-04-01
The occurrence of aquatic pollution is an inevitable environmental impact resulting from human civilization and societal advancement. Either from the natural or anthropogenic sources, the aqueous contaminants enter the natural environment and aggravate its quality. To assure the aquatic environment quality, the attached-growth biological degradation is often applied to removing organic contaminants by introducing contaminated water into a porous media which is covered by microorganism. Additionally, many natural aquatic systems also form such similar mechanism to increase their self-purification capability. To better understand this transport phenomenon and degradation mechanism in the biofilm for future application, the mathematic characterization of organic contaminant diffusion within the biofilm requires further exploration. The present study aimed to formulate a mathematic representation to quantify the diffusion of the organic contaminant in the biofilm. The BOD was selected as the target contaminant. A series of experiments were conducted to quantify the BOD diffusion in the biofilm under the conditions of influent BOD variation from 50 to 300 mg/L, COD:N:P ratios of 100:5:1 and 100:15:3, with or without auxiliary aeration. For diffusion coefficient calculation, the boundary condition of zero diffusion at the interface between microbial phase and contact media was assumed. With the principle of conservation of mass, the removed contaminants equal those that diffuse into the biofilm, and eq 1 results, and the diffusion coefficient (i.e., eq 2) can be solved through calculus with equations from table of integral. ∂2Sf- Df ∂z2 = Rf (1) --(QSin--QSout)2Y--- Df = 2μmaxxf(Sb + Ks ln-Ks-) Sb+Ks (2) Using the obtained experimental data, the diffusion coefficient was calculated to be 2.02*10-6 m2/d with influent COD of 50 mg/L at COD:N:P ratio of 100:5:1 with aeration, and this coefficient increased to 6.02*10-6 m2/d as the influent concentration increased to 300 mg/L. Meanwhile, the diffusion coefficient decreased to 2.61*10-7 m2/d as the retention time increased to 3 hours. Generally, the variation in diffusion coefficients between different COD:N:P ratios exhibits similar pattern with a slight decrease for the ratio of 100:15:3. The difference in diffusion coefficients between 1 and 2 hours was apparently greater than that between 2 and 3 hours, implying the diffusion was a critical factor for contaminant removal for the treatment condition with retention time of 1 hour or less, because higher retention time leads to better microbial degradation due to sufficient contact time for biological reactions. For 1 hour retention time, the increase in diffusion coefficient becomes limited as the influent COD concentration was equal to or above 150 mg/L. These obtained diffusion coefficients were applied to estimating the treatment efficiency for real domestic sewage. The result was found that the estimated effluent BOD concentrations were quite comparable to that obtained through experimental measurements.
Wei, Ouyang; Cai, Guan-Qing; Huang, Hao-Bo; Geng, Xiao-Jun
2014-06-01
The soil respiration, nitrification and denitrification processes play an important role on soil nitrogen transformation and diffuse nitrogen loading. These processes are also the chains for soil circle. In this study, the Zhegao watershed located north of Chaohu Lake was selected to explore the interactions of these processes with diffuse nitrogen pollution. The BaPS (Barometric Process Separation) was applied to analyze the soil respiration, nitrification and denitrification processes in farmland and forest. The SWAT (Soil and Water Assessment Tool) simulated the temporal and spatial pattern of diffuse nitrogen loading. As the expanding of farmland and higher level of fertilization, the yearly mean loading of diffuse nitrogen increased sustainably from 1980-1995 to 1996-2012. The monthly loading in 1996-2012 was also higher than that in the period of 1980-1995, which closely related to the precipitation. The statistical analysis indicated that there was a significant difference between two periods. The yearly averaged loading of the whole watershed in 1996-2012 was 10.40 kg x hm(-2), which was 8.10 kg x hm(-2) in 1980-1995. The variance analysis demonstrated that there was also a big difference between the spatial distributions of two periods. The forest soil had much higher soil respiration than the farmland soil. But the farmland had higher nitrification and denitrification rates. The more intensive nitrogen transformation in the farmland contributed to the less diffuse nitrogen loading. As the nitrification rate of farmland was higher than denitrification rate, agricultural diffuse nitrate nitrogen loading would increase and organic nitrogen loading would reduce. The analysis of soil respiration, nitrification and denitrification is helpful for the study of soil nitrogen circle form the aspect of soil biology, which also benefits the control of agricultural diffuse nitrogen pollution.
[Numerical simulation study of SOA in Pearl River Delta region].
Cheng, Yan-li; Li, Tian-tian; Bai, Yu-hua; Li, Jin-long; Liu, Zhao-rong; Wang, Xue-song
2009-12-01
Secondary organic aerosols (SOA) is an important component of the atmospheric particle pollution, thus, determining the status and sources of SOA pollution is the premise of deeply understanding the occurrence, development law and the influence factors of the atmospheric particle pollution. Based on the pollution sources and meteorological data of Pearl River Delta region, the study used the two-dimensional model coupled with SOA module to stimulate the status and source of SOA pollution in regional scale. The results show: the generation of SOA presents obvious characteristics of photochemical reaction, and the high concentration appears at about 14:00; SOA concentration is high in some areas of Guangshou and Dongguan with large pollution source-emission, and it is also high in some areas of Zhongshan, Zhuhai and Jiangmen which are at downwind position of Guangzhou and Dongguan. Contribution ratios of several main pollution sources to SOA are: biogenic sources 72.6%, mobile sources 30.7%, point sources 12%, solvent and oil paint sources 12%, surface sources less than 5% respectively.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-14
... National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources AGENCY... Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources. Among the... Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources (CMAS) on October...
NASA Astrophysics Data System (ADS)
Zhang, Y. Y.; Shao, Q. X.; Ye, A. Z.; Xing, H. T.; Xia, J.
2016-02-01
Integrated water system modeling is a feasible approach to understanding severe water crises in the world and promoting the implementation of integrated river basin management. In this study, a classic hydrological model (the time variant gain model: TVGM) was extended to an integrated water system model by coupling multiple water-related processes in hydrology, biogeochemistry, water quality, and ecology, and considering the interference of human activities. A parameter analysis tool, which included sensitivity analysis, autocalibration and model performance evaluation, was developed to improve modeling efficiency. To demonstrate the model performances, the Shaying River catchment, which is the largest highly regulated and heavily polluted tributary of the Huai River basin in China, was selected as the case study area. The model performances were evaluated on the key water-related components including runoff, water quality, diffuse pollution load (or nonpoint sources) and crop yield. Results showed that our proposed model simulated most components reasonably well. The simulated daily runoff at most regulated and less-regulated stations matched well with the observations. The average correlation coefficient and Nash-Sutcliffe efficiency were 0.85 and 0.70, respectively. Both the simulated low and high flows at most stations were improved when the dam regulation was considered. The daily ammonium-nitrogen (NH4-N) concentration was also well captured with the average correlation coefficient of 0.67. Furthermore, the diffuse source load of NH4-N and the corn yield were reasonably simulated at the administrative region scale. This integrated water system model is expected to improve the simulation performances with extension to more model functionalities, and to provide a scientific basis for the implementation in integrated river basin managements.
Cao, Jing; Hou, Zeying; Li, Zekun; Chu, Zhaosheng; Yang, Pingping; Zheng, Binghui
2018-08-01
The present study was carried out in a mesotrophic subtropical plateau lake, Erhai, located in southwest of China. The succession of phytoplankton functional groups and the environmental variables in the lake were investigated from January 2013 to December 2015. The lake had strong radiation levels and a low-temperature amplitude because of its high elevation and strongly mixed water. It was highly affected by the subtropical monsoon precipitation, and its pollution sources were from diffuse pollution caused by rainfall runoff. Altogether 112 genera, 16 functional groups and 4 predominant functional groups, L M (Microcystis), P (Melosira, Fragilaria, Closterium), T (Mougeotia), T (Psephonema aenigmaticum) and Y (Cryptomonas), were identified, and the predominant functional groups demonstrated strong seasonal variations. Group T (Mougeotia) dominated from the winter to early spring, with strong lake water mixing. Group P replaced group T (Mougeotia) as the dominate group of the phytoplankton community in the spring (March to May), with clear water and increased temperature. With the arrival of the monsoon rainy season in the summer, large amounts of external pollutants were brought into the lake via rainfall runoff, allowing group L M (Microcystis) to become dominant. Meanwhile, the intensive nutrient inputs after the rainstorm in the summer, combined with high temperatures and decreased radiation, led to the sustained growth of group L M in the autumn and even ultimately triggered Microcystis blooming. Group T (P. aenigmaticum) was a particular phytoplankton genus predominant in the autumn, which displayed a seasonal variation similar to that of group L M . This study underscores the usefulness of phytoplankton functional groups in studying phytoplankton succession in subtropical plateau lakes impacted by diffuse pollution, in which the succession of phytoplankton functional groups can be significantly affected by rainfall runoff, which altered variables such as nutrients, high temperatures and radiation. Copyright © 2018 Elsevier B.V. All rights reserved.
Ockenden, M C; Quinton, J N; Favaretto, N; Deasy, C; Surridge, B
2014-07-01
Surface water quality in the UK and much of Western Europe has improved in recent decades, in response to better point source controls and the regulation of fertilizer, manure and slurry use. However, diffuse sources of pollution, such as leaching or runoff of nutrients from agricultural fields, and micro-point sources including farmyards, manure heaps and septic tank sewerage systems, particularly systems without soil adsorption beds, are now hypothesised to contribute a significant proportion of the nutrients delivered to surface watercourses. Tackling such sources in an integrated manner is vital, if improvements in freshwater quality are to continue. In this research, we consider the combined effect of constructing small field wetlands and improving a septic tank system on stream water quality within an agricultural catchment in Cumbria, UK. Water quality in the ditch-wetland system was monitored by manual sampling at fortnightly intervals (April-October 2011 and February-October 2012), with the septic tank improvement taking place in February 2012. Reductions in nutrient concentrations were observed through the catchment, by up to 60% when considering total phosphorus (TP) entering and leaving a wetland with a long residence time. Average fluxes of TP, soluble reactive phosphorus (SRP) and ammonium-N (NH4-N) at the head of the ditch system in 2011 (before septic tank improvement) compared to 2012 (after septic tank improvement) were reduced by 28%, 9% and 37% respectively. However, TP concentration data continue to show a clear dilution with increasing flow, indicating that the system remained point source dominated even after the septic tank improvement.
Nie, Zeyu; Wu, Xiaodong; Huang, Haomin; Fang, Xiaomin; Xu, Chen; Wu, Jianyu; Liang, Xinqiang; Shi, Jiyan
2016-05-01
Profound understanding of behaviors of organic matter from sources to multistage rivers assists watershed management for improving water quality of river networks in rural areas. Ninety-one water samples were collected from the three orders of receiving rivers in a typical combined polluted subcatchment (diffuse agricultural pollutants and domestic sewage) located in China. Then, the fluorescent dissolved organic matter (FDOM) information for these samples was determined by the excitation-emission matrix coupled with parallel factor analysis (EEM-PARAFAC). Consequently, two typical humic-like (C1 and C2) and other two protein-like (C3 and C4) components were separated. Their fluorescence peaks were located at λ ex/em = 255(360)/455, <250(320)/395, 275/335, and <250/305 nm, which resembled the traditional peaks of A + C, A + M, T, and B, respectively. In addition, C1 and C2 accounted for the dominant contributions to FDOM (>60 %). Principal component analysis (PCA) further demonstrated that, except for the autochthonous produced C4, the allochthonous components (C1 and C2) had the same terrestrial origins, but C3 might possess the separate anthropogenic and biological sources. Moreover, the spatial heterogeneity of contamination levels was noticeable in multistage rivers, and the allochthonous FDOM was gradually homogenized along the migration directions. Interestingly, the average content of the first three PARAFAC components in secondary tributaries and source pollutants had significantly higher levels than that in subsequent receiving rivers, thus suggesting that the supervision and remediation for secondary tributaries would play a prominent role in watershed management works.
Global baseline data on phosphorus pollution of large lakes
NASA Astrophysics Data System (ADS)
Fink, Gabriel; Flörke, Martina; Alcamo, Joseph
2016-04-01
Lakes are exposed to harmful eutrophication which is the most concerning water quality issue on global scale. Eutrophication is caused by phosphorous pollution in most lakes. Hence, global consistent base line data on phosphorus loadings are needed to assess future sustainable development. We used the modeling framework WaterGAP3 to calculate present total phosphorus loadings to the world's largest lakes. Estimates of modeled total phosphorus (TP) loadings as well as the contributions of different sectors were successfully validated against measured data. Based on these findings, annual total phosphorus loadings to lakes were calculated for diffuse and point sources according to the different sectors domestic, manufacturing, urban surface runoff, agriculture and background for the time period 1990 to 2010. Our results show high phosphorus loadings into lakes in southern latitudes. On global average, industrial fertilizer is the main anthropogenic source while background loadings are low in comparison. Nevertheless, both features indicate a high potential to reduce the exposure to eutrophication in lakes which are faced with high phosphor inputs. The global average of TP loadings was 7% higher in the time period 2005-2010 than in the period 1990-1995. The global average in 2005-2010 results from an increase in TP loadings of 79% in South America, which was dampened by a decrease in Europe, North America, and Asia. Chinese lakes were exposed to massive increasing phosphorus loadings, too. Both increasing and decreasing trends are caused primarily by changing industrial fertilizer application rates. In conclusion, this study provides a consistent and model based synopsis of global trends and sources of phosphorus loadings to large lakes. The estimates of phosphorus pollution of lakes present a basis for assessing and managing the global eutrophication problem.
NASA Astrophysics Data System (ADS)
Yamada, Tetsuji; Kao, Chih-Yue; Bunker, Susan
We apply a three-dimensional meteorological model with a four-dimensional data assimilation (4-DDA) technique to simulate diurnal variations of wind, temperature, water vapor, and turbulence in a region extending from the west coast to east of the Rockies and from northern Mexico to Wyoming. The wind data taken during the 1985 SCENES ( Subregional Cooperative Electric Utility, Dept. of Defense, National Park Service, and Environmental Protection Agency Study on Visibility) field experiments are successfully assimilated into the model through the 4-DDA technique by 'nudging' the modeled winds toward the observed winds. The modeled winds and turbulence fields are then used in a Lagrangian random-particle statistical model to investigate how pollutants from potential sources are transported and diffused. Finally, we calculate the ground concentrations through a kernel density estimator. Two scenarios in different weather patterns are investigated with simulation periods up to 6 days. One is associated with the evolution of a surface cold front and the other under a high-pressure stagnant condition. In the frontal case, the impact of air-mass movement on the ground concentrations of pollutants released from the Los Angeles area is well depicted by the model. Also, the pollutants produced from Los Angeles can be transported to the Grand Canyon area within 24 h. However, if we use only the data that were obtained from the regular NWS rawinsonde network, whose temporal and spatial resolutions are coarser than those of the special network, the plume goes north-northeast and never reaches the Grand Canyon area. In the stagnant case, the pollutants meander around the source area and can have significant impact on local air quality.
NASA Astrophysics Data System (ADS)
Ghiglieri, Giorgio; Barbieri, Giulio; Vernier, Antonio; Carletti, Alberto; Demurtas, Nicola; Pinna, Rosanna; Pittalis, Daniele
2009-12-01
SummaryThe paper describes the methodological and innovative approach, which aims to evaluate the potential risk of nitrate pollution in aquifers from agricultural practices by combining intrinsic aquifer vulnerability to contamination, according to the SINTACS R5 method, with agricultural nitrates hazard assessment, according to the IPNOA index. The proposed parametric model adopts a geographically based integrated evaluation system, comprising qualitative and semi-quantitative indicators. In some cases, the authors have modified this model, revising and adjusting scores and weights of the parameter to account for the different environmental conditions, and calibrating accordingly. The method has been successfully implemented and validated in the pilot area of the Alghero coastal plain (northwestern Sardinia, Italy) where aquifers with high productivity are present. The classes with a major score (high potential risk) are in the central part of the plain, in correspondence with the most productive aquifers, where most actual or potential pollution sources are concentrated. These are mainly represented by intensive agricultural activities, by industrial agglomerate and diffused urbanisation. For calibrating the model and optimizing and/or weighting the examined factors, the modelling results were validated by comparison with groundwater quality data, in particular nitrate content, and with the potential pollution sources census data. The parametric method is a popular approach to groundwater vulnerability assessment, in contrast to groundwater flow model and statistical method ones: it is, indeed, relatively inexpensive and straightforward, and use data commonly available or that can be estimated. The zoning of nitrate vulnerable areas provides regional authorities with a useful decision support tool for planning land-use properly managing groundwater and combating and/or mitigating desertification processes. However, a careful validation of the results is indispensable for reliable application.
Water Pollution, Causes and Cures.
ERIC Educational Resources Information Center
Manufacturing Chemists Association, Washington, DC.
This commentary on sources of water pollution and water pollution treatment systems is accompanied by graphic illustrations. Sources of pollution such as lake bottom vegetation, synthetic organic pollutants, heat pollution, radioactive substance pollution, and human and industrial waste products are discussed. Several types of water purification…
Benes, V; Pĕkný, V; Skorepa, J; Vrba, J
1989-01-01
In several regions of Czechoslovakia with intensive agricultural production, the correlation between the amount of nitrogen fertilizer applied and the nitrate content in groundwater has been recognized. Nitrate pollution of groundwater is considered to be the most serious source of nonpoint pollution in Czechoslovakia. A program of research into the effects of farming activities on groundwater quality in Czechoslovakia is under way on experimental fields (20 to 30 hectares) and, simultaneously, in regions in which shallow, vulnerable aquifers occur. The importance of the soil organic matter's stability for maintaining the groundwater quality is emphasized. Research based on nitrogen and organic carbon balance has shown that the restoration of a soil-groundwater system is a complicated process that usually requires changes in the extent and intensity of agricultural activities and consistent attention to the effects produced by natural conditions. Regional investigation of the impact of farming on shallow aquifers in the fluvial deposits of the Elbe River in Bohemia has proved the hydrochemical instability and vertical hydrochemical heterogeneity of these aquifers. The WASTEN deterministic model was used for modeling the transport and transformation of various types of inorganic fertilizers. The input data is based on laboratory and field measurements. Special topics are the verification of model calculations and the time and spatial variability of input data with respect to the unsaturated zone. The research results are being used for making regional and national agro-groundwater managerial schemes more precise, as well as for decision-making. PMID:2559844
NASA Astrophysics Data System (ADS)
Halenka, T.; Bednar, J.; Brechler, J.
The spatial distribution of air pollution on the regional scale (Bohemian region) is simulated by means of Charles University puff model SMOG. The results are used for the assessment of the concentration fields of ozone, nitrogen oxides and other ozone precursors. Current improved version of the model covers up to 16 groups of basic compounds and it is based on trajectory computation and puff interaction both by means of Gaussian diffusion mixing and chemical reactions of basic species. Gener- ally, the method used for trajectory computation is valuable mainly for episodes sim- ulation, nevertheless, climatological study can be solved as well by means of average wind rose. For the study being presented huge database of real emission sources was incorporated with all kind of sources included. Some problem with the background values of concentrations was removed. The model SMOG has been nested into the forecast model ETA to obtain appropriate meteorological data input. We can estimate air pollution characteristics both for episodes analysis and the prediction of future air quality conditions. Necessary prognostic variables from the numerical weather pre- diction model are taken for the region of the central Bohemia, where the original puff model was tested. We used mainly 850 hPa wind field for computation of prognos- tic trajectories, the influence of surface temperature as a parameter of photochemistry reactions as well as the effect of cloudness has been tested.
Removing ammonium from water and wastewater using cost-effective adsorbents: A review.
Huang, Jianyin; Kankanamge, Nadeeka Rathnayake; Chow, Christopher; Welsh, David T; Li, Tianling; Teasdale, Peter R
2018-01-01
Ammonium is an important nutrient in primary production; however, high ammonium loads can cause eutrophication of natural waterways, contributing to undesirable changes in water quality and ecosystem structure. While ammonium pollution comes from diffuse agricultural sources, making control difficult, industrial or municipal point sources such as wastewater treatment plants also contribute significantly to overall ammonium pollution. These latter sources can be targeted more readily to control ammonium release into water systems. To assist policy makers and researchers in understanding the diversity of treatment options and the best option for their circumstance, this paper produces a comprehensive review of existing treatment options for ammonium removal with a particular focus on those technologies which offer the highest rates of removal and cost-effectiveness. Ion exchange and adsorption material methods are simple to apply, cost-effective, environmentally friendly technologies which are quite efficient at removing ammonium from treated water. The review presents a list of adsorbents from the literature, their adsorption capacities and other parameters needed for ammonium removal. Further, the preparation of adsorbents with high ammonium removal capacities and new adsorbents is discussed in the context of their relative cost, removal efficiencies, and limitations. Efficient, cost-effective, and environmental friendly adsorbents for the removal of ammonium on a large scale for commercial or water treatment plants are provided. In addition, future perspectives on removing ammonium using adsorbents are presented. Copyright © 2017. Published by Elsevier B.V.
Khairy, Mohammed A; Luek, Jenna L; Dickhut, Rebecca; Lohmann, Rainer
2016-09-01
The Antarctic continent is among the most pristine regions; yet various organic contaminants have been measured there routinely. Air and snow samples were collected during the austral spring (October-November, 2010) along the western Antarctic Peninsula and analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) to assess the relative importance of long-range transport versus local primary or secondary emissions. Highest concentrations of PCBs, PBDEs and DDTs were observed in the glacier's snow sample, highlighting the importance of melting glaciers as a possible secondary source of legacy pollutants to the Antarctic. In the atmosphere, contaminants were mainly found in the vapor phase (>65%). Hexachlorobenzene (33.6 pg/m(3)), PCBs (11.6 pg/m(3)), heptachlor (5.64 pg/m(3)), PBDEs (4.22 pg/m(3)) and cis-chlordane (2.43 pg/m(3)) were the most abundant contaminants. In contrast to other compounds, PBDEs seem to have originated from local sources, possibly the research station itself. Gas-particle partitioning for analytes were better predicted using the adsorption partitioning model than an octanol-based absorption approach. Diffusive flux calculations indicated that net deposition is the dominant pathway for PBDEs and chlordanes, whereas re-volatilization from snow (during melting or metamorphosis) was observed for PCBs and some OCPs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Monitor-based evaluation of pollutant load from urban stormwater runoff in Beijing.
Liu, Y; Che, W; Li, J
2005-01-01
As a major pollutant source to urban receiving waters, the non-point source pollution from urban runoff needs to be well studied and effectively controlled. Based on monitoring data from urban runoff pollutant sources, this article describes a systematic estimation of total pollutant loads from the urban areas of Beijing. A numerical model was developed to quantify main pollutant loads of urban runoff in Beijing. A sub-procedure is involved in this method, in which the flush process influences both the quantity and quality of stormwater runoff. A statistics-based method was applied in computing the annual pollutant load as an output of the runoff. The proportions of pollutant from point-source and non-point sources were compared. This provides a scientific basis for proper environmental input assessment of urban stormwater pollution to receiving waters, improvement of infrastructure performance, implementation of urban stormwater management, and utilization of stormwater.
Variability of Solar Radiation under Cloud-Free Skies in China: The Role of Aerosols
NASA Technical Reports Server (NTRS)
Qian, Yun; Wang, Weiguo; Leung, L. ruby; Kaiser, Dale P.
2007-01-01
In this study, we analyzed long-term surface global and diffuse solar radiation, aerosol single scattering albedo (SSA), and relative humidity (RH) from China. Our analysis reveals that much of China experienced significant decreases in global solar radiation (GSR) and increases in diffuse solar radiation under cloud-free skies between the 1960s and 1980s. With RH and aerosol SSA being rather constant during that time period, we suggest that the increasing aerosol loading from emission of pollutants is responsible for the observed reduced GSR and increased diffuse radiation in cloud-free skies. Although pollutant emissions continue to increase after the 1980s, the increment of aerosol SSA since 1980s can partly explain the transition of GSR from a decreasing trend to no apparent trend around that time. Preliminary analysis is also provided on the potential role of RH in affecting the global and diffuse solar radiation reaching the earth surface.
Vinten, A J A; Martin-Ortega, J; Glenk, K; Booth, P; Balana, B B; MacLeod, M; Lago, M; Moran, D; Jones, M
2012-04-30
The Water Framework Directive (WFD) aims to deliver good ecological status (GES) for Europe's waters. It prescribes the use of economic principles, such as derogation from GES on grounds of disproportionate costs of mitigation. This paper proposes an application of the proportionality principle to mitigation of phosphorus (P) pollution of 544 Scottish lochs at national and local water body scales. P loading estimates were derived from a national diffuse pollution screening tool. For 293 of these lochs (31% of the loch area), GES already occurred. Mitigation cost-effectiveness was assessed using combined mitigation cost curves for managed grassland, rough grazing, arable land, sewage and septic tank sources. These provided sufficient mitigation (92% of national P load) for GES to be achieved on another 31% of loch area at annualised cost of £2.09 m/y. Mitigation of the residual P loading preventing other lochs achieving GES was considered by using a "mop-up" cost of £200/kg P (assumed cost effectiveness of removal of P directly from lochs), leading to a total cost of £189 m/y. Lochs were ranked by mitigation costs per loch area to give a national scale marginal mitigation cost curve. A published choice experiment valuation of WFD targets for Scottish lochs was used to estimate marginal benefits at national scale and combined with the marginal cost curve. This gave proportionate costs of £5.7 m/y leading to GES in 72% of loch area. Using national mean marginal benefits with a scheme to estimate changes in individual loch value with P loading gave proportionate costs of £25.6 m/y leading to GES in 77% of loch area (491 lochs). Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
McCray, J. E.; Downs, W.; Falta, R. W.; Housley, T.
2005-12-01
DNAPL sources of carbon tetrachloride (CT) vapors are of interest at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL). The site is underlain by thick fractured basalt that includes sedimentary interbeds, each are a few meters thick. Daily atmospheric pressure fluctuations serve as driving forces for CT vapor transport in the subsurface. Other important transport processes for vapor movement include gas-phase diffusion and density-driven transport. The objective of this research is to investigate the influence and relative importance of these processes on gaseous transport of CT. Gas pressure and vapor concentration measurements were conducted at various depths in two wells. A numerical multiphase flow model (TOUGH2), calibrated to field pressure data, is used to conduct sensitivity analyses to elucidate the importance of the different transport mechanisms. Results show that the basalt is highly permeable to vertical air flow. The pressure dampening occurs mainly in the sedimentary interbeds. Model-calibrated permeability values for the interbeds are similar to those obtained in a study by the U.S. Geological Survey for shallow sediments, and an order of magnitude higher than column-scale values obtained by previous studies conducted by INEEL scientists. The transport simulations indicate that considering the effect of barometric pressure changes is critical to simulating transport of pollutants in the vadose zone above the DNAPL source. Predicted concentrations can be orders of magnitude smaller than actual concentrations if the effect is not considered. Below the DNAPL vapor source, accounting for density and diffusion alone would yield acceptable results provided that a 20% error in concentrations are acceptable, and that simulating concentrations trends (and not actual concentrations) is the primary goal.
Determination of geostatistically representative sampling locations in Porsuk Dam Reservoir (Turkey)
NASA Astrophysics Data System (ADS)
Aksoy, A.; Yenilmez, F.; Duzgun, S.
2013-12-01
Several factors such as wind action, bathymetry and shape of a lake/reservoir, inflows, outflows, point and diffuse pollution sources result in spatial and temporal variations in water quality of lakes and reservoirs. The guides by the United Nations Environment Programme and the World Health Organization to design and implement water quality monitoring programs suggest that even a single monitoring station near the center or at the deepest part of a lake will be sufficient to observe long-term trends if there is good horizontal mixing. In stratified water bodies, several samples can be required. According to the guide of sampling and analysis under the Turkish Water Pollution Control Regulation, a minimum of five sampling locations should be employed to characterize the water quality in a reservoir or a lake. The European Union Water Framework Directive (2000/60/EC) states to select a sufficient number of monitoring sites to assess the magnitude and impact of point and diffuse sources and hydromorphological pressures in designing a monitoring program. Although existing regulations and guidelines include frameworks for the determination of sampling locations in surface waters, most of them do not specify a procedure in establishment of monitoring aims with representative sampling locations in lakes and reservoirs. In this study, geostatistical tools are used to determine the representative sampling locations in the Porsuk Dam Reservoir (PDR). Kernel density estimation and kriging were used in combination to select the representative sampling locations. Dissolved oxygen and specific conductivity were measured at 81 points. Sixteen of them were used for validation. In selection of the representative sampling locations, care was given to keep similar spatial structure in distributions of measured parameters. A procedure was proposed for that purpose. Results indicated that spatial structure was lost under 30 sampling points. This was as a result of varying water quality in the reservoir due to inflows, point and diffuse inputs, and reservoir hydromorphology. Moreover, hot spots were determined based on kriging and standard error maps. Locations of minimum number of sampling points that represent the actual spatial structure of DO distribution in the Porsuk Dam Reservoir
Do outdoor environmental noise and atmospheric NO2 levels spatially overlap in urban areas?
Tenailleau, Quentin M; Bernard, Nadine; Pujol, Sophie; Parmentier, Anne-Laure; Boilleaut, Mathieu; Houot, Hélène; Joly, Daniel; Mauny, Frédéric
2016-07-01
The urban environment holds numerous emission sources for air and noise pollution, creating optimum conditions for environmental multi-exposure situations. Evaluation of the joint-exposure levels is the main obstacle for multi-exposure studies and one of the biggest challenges of the next decade. The present study aims to describe the noise/NO2 multi-exposure situations in the urban environment by exploring the possible discordant and concordant situations of both exposures. Fine-scale diffusion models were developed in the European medium-sized city of Besançon (France), and a classification method was used to evaluate the multi-exposure situations in the façade perimeter of 10,825 buildings. Although correlated (Pearson's r = 0.64, p < 0.01), urban spatial distributions of the noise and NO2 around buildings do not overlap, and 30% of the buildings were considered to be discordant in terms of the noise and NO2 exposure levels. This discrepancy is spatially structured and associated with variables describing the building's environment. Our results support the presence of several co-existing, multi-exposure situations across the city impacted by both the urban morphology and the emission and diffusion/propagation phases of each pollutant. Identifying the mechanisms of discrepancy and convergence of multi-exposure situations could help improve the health risk assessment and public health. Copyright © 2016 Elsevier Ltd. All rights reserved.
Hackstadt, Amber J; Peng, Roger D
2014-11-01
Time series studies have suggested that air pollution can negatively impact health. These studies have typically focused on the total mass of fine particulate matter air pollution or the individual chemical constituents that contribute to it, and not source-specific contributions to air pollution. Source-specific contribution estimates are useful from a regulatory standpoint by allowing regulators to focus limited resources on reducing emissions from sources that are major contributors to air pollution and are also desired when estimating source-specific health effects. However, researchers often lack direct observations of the emissions at the source level. We propose a Bayesian multivariate receptor model to infer information about source contributions from ambient air pollution measurements. The proposed model incorporates information from national databases containing data on both the composition of source emissions and the amount of emissions from known sources of air pollution. The proposed model is used to perform source apportionment analyses for two distinct locations in the United States (Boston, Massachusetts and Phoenix, Arizona). Our results mirror previous source apportionment analyses that did not utilize the information from national databases and provide additional information about uncertainty that is relevant to the estimation of health effects.
Wang, Long; Wei, Jiahua; Huang, Yuefei; Wang, Guangqian; Maqsood, Imran
2011-07-01
Many urban nonpoint source pollution models utilize pollutant buildup and washoff functions to simulate storm runoff quality of urban catchments. In this paper, two urban pollutant washoff load models are derived using pollutant buildup and washoff functions. The first model assumes that there is no residual pollutant after a storm event while the second one assumes that there is always residual pollutant after each storm event. The developed models are calibrated and verified with observed data from an urban catchment in the Los Angeles County. The application results show that the developed model with consideration of residual pollutant is more capable of simulating nonpoint source pollution from urban storm runoff than that without consideration of residual pollutant. For the study area, residual pollutant should be considered in pollutant buildup and washoff functions for simulating urban nonpoint source pollution when the total runoff volume is less than 30 mm. Copyright © 2011 Elsevier Ltd. All rights reserved.
A national look at water quality
Gilliom, Robert J.; Mueller, David K.; Zogorski, John S.; Ryker, Sarah J.
2002-01-01
Most water-quality problems we face today result from diffuse "nonpoint" sources of pollution from agricultural land, urban development, forest harvesting and the atmosphere (U.S. Army Corps of Engineers et al., 1999). It is difficult to quantify nonpoint sources because the contaminants they deliver vary in composition and concentrations from hour to hour and season to season. Moreover, the nature of the contamination is complex and varied. When Congress enacted the Clean Water Act 30 years ago, attention was focused on water-quality issues related to the sanitation of rivers and streams - bacteria counts, oxygen in the water for fish, nutrients, temperature, and salinity. Now, attention is turning to the hundreds of synthetic organic compounds like pesticides used in agricultural and residential areas, volatile organics in solvents and gasoline, microbial and viral contamination, and pharmaceuticals and hormones.
Coastal Research Imaging Spectrometer
NASA Technical Reports Server (NTRS)
Lucey, Paul G.; Williams, Timothy; Horton, Keith A.
2002-01-01
The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote-sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly.
NASA Astrophysics Data System (ADS)
Li, D.
2016-12-01
Sudden water pollution accidents are unavoidable risk events that we must learn to co-exist with. In China's Taihu River Basin, the river flow conditions are complicated with frequently artificial interference. Sudden water pollution accident occurs mainly in the form of a large number of abnormal discharge of wastewater, and has the characteristics with the sudden occurrence, the uncontrollable scope, the uncertainty object and the concentrated distribution of many risk sources. Effective prevention of pollution accidents that may occur is of great significance for the water quality safety management. Bayesian networks can be applied to represent the relationship between pollution sources and river water quality intuitively. Using the time sequential Monte Carlo algorithm, the pollution sources state switching model, water quality model for river network and Bayesian reasoning is integrated together, and the sudden water pollution risk assessment model for river network is developed to quantify the water quality risk under the collective influence of multiple pollution sources. Based on the isotope water transport mechanism, a dynamic tracing model of multiple pollution sources is established, which can describe the relationship between the excessive risk of the system and the multiple risk sources. Finally, the diagnostic reasoning algorithm based on Bayesian network is coupled with the multi-source tracing model, which can identify the contribution of each risk source to the system risk under the complex flow conditions. Taking Taihu Lake water system as the research object, the model is applied to obtain the reasonable results under the three typical years. Studies have shown that the water quality risk at critical sections are influenced by the pollution risk source, the boundary water quality, the hydrological conditions and self -purification capacity, and the multiple pollution sources have obvious effect on water quality risk of the receiving water body. The water quality risk assessment approach developed in this study offers a effective tool for systematically quantifying the random uncertainty in plain river network system, and it also provides the technical support for the decision-making of controlling the sudden water pollution through identification of critical pollution sources.
Sun, Jie; Wang, Yuesi; Wu, Fangkun; Tang, Guiqian; Wang, Lili; Wang, Yinghong; Yang, Yuan
2018-05-01
In recent years, photochemical smog and gray haze-fog have frequently appeared over northern China. To determine the spatial distribution of volatile organic compounds (VOC) during a pollution period, tethered balloon flights were conducted over a suburban site on the North China Plain. Statistical analysis showed that the VOCs concentrations peaked at the surface, and decreased with altitude. A rapid decrease appeared from the surface to 400 m, with concnetrations of alkanes, alkenes, aromatics and halocarbons decreasing by 48.0%, 53.3%, 43.3% and 51.1%, respectively. At heights in the range of 500-1000 m, alkenes concnetrations decline by 40.2%; alkanes and halocarbons concnetrations only decreased by 24.8% and 6.4%, respectively; and aromatics increased slightly by 5.5%. High concentrations VOCs covered a higher range of height (400 m) on heavy pollution days due to lacking of diffusion power. The VOCs concentrations decreased by 50% at 200 m on light pollution days. The transport of air mass affected the composition and concentration of high-altitude VOCs, especially on lightly polluted days. These air masses originated in areas with abundant traffic and combustion sources. Reactive aromatics (k OH >20,000 ppm -1 min -1 and k OH <20,000 ppm -1 min -1 ) were the main contributor to the ozone formation, accounting for 37%, on the surface on light pollution days. The contribution increased to 52% with pollution aggravated, and increased to 64% with height. The contributions of reactive aromatics were influenced by the degree of air mass aging. Under the umbrella of aging air mass, the contribution of reactive aromatics increased with height. Copyright © 2017. Published by Elsevier Ltd.
Microfabricated diffusion source
Oborny, Michael C [Albuquerque, NM; Frye-Mason, Gregory C [Cedar Crest, NM; Manginell, Ronald P [Albuquerque, NM
2008-07-15
A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.
Changing Regulations of COD Pollution Load of Weihe River Watershed above TongGuan Section, China
NASA Astrophysics Data System (ADS)
Zhu, Lei; Liu, WanQing
2018-02-01
TongGuan Section of Weihe River Watershed is a provincial section between Shaanxi Province and Henan Province, China. Weihe River Watershed above TongGuan Section is taken as the research objective in this paper and COD is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a method—characteristic section load (CSLD) method is suggested and point and non-point source pollution loads of Weihe River Watershed above TongGuan Section are calculated in the rainy, normal and dry season in 2013. The results show that the monthly point source pollution loads of Weihe River Watershed above TongGuan Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above TongGuan Section change greatly and the non-point source pollution load proportions of total pollution load of COD decrease in the rainy, wet and normal period in turn.
On the use of coprostanol to identify source of nitrate pollution in groundwater
NASA Astrophysics Data System (ADS)
Nakagawa, Kei; Amano, Hiroki; Takao, Yuji; Hosono, Takahiro; Berndtsson, Ronny
2017-07-01
Investigation of contaminant sources is indispensable for developing effective countermeasures against nitrate (NO3-) pollution in groundwater. Known major nitrogen (N) sources are chemical fertilizers, livestock waste, and domestic wastewater. In general, scatter diagrams of δ18O and δ15N from NO3- can be used to identify these pollution sources. However, this method can be difficult to use for chemical fertilizers and livestock waste sources due to the overlap of δ18O and δ15N ranges. In this study, we propose to use coprostanol as an indicator for the source of pollution. Coprostanol can be used as a fecal contamination indicator because it is a major fecal sterol formed by the conversion of cholesterol by intestinal bacteria in the gut of higher animals. The proposed method was applied to investigate NO3- pollution sources for groundwater in Shimabara, Nagasaki, Japan. Groundwater samples were collected at 33 locations from March 2013 to November 2015. These data were used to quantify relationships between NO3-N, δ15N-NO3-, δ18O-NO3-, and coprostanol. The results show that coprostanol has a potential for source identification of nitrate pollution. For lower coprostanol concentrations (<30 ng L-1) in the nitrate-polluted group, fertilizer is likely to be the predominant source of NO3-. However, higher concentration coprostanol samples in the nitrate-polluted group can be related to pollution from livestock waste. Thus, when conventional diagrams of isotopic ratios cannot distinguish pollution sources, coprostanol may be a useful tool.
ERIC Educational Resources Information Center
Nuttonson, M. Y., Ed.
Twelve papers were translated from Russian: Automation of Information Processing Involved in Experimental Studies of Atmospheric Diffusion, Micrometeorological Characteristics of Atmospheric Pollution Conditions, Study of theInfluence of Irregularities of the Earth's Surface on the Air Flow Characteristics in a Wind Tunnel, Use of Parameters of…
40 CFR 464.25 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Copper Casting... existing sources. (a) Casting Quench Operations. PSES Pollutant or pollutant property Maximum for any 1 day... monitoring) 1.2 0.399 (b) Direct Chill Casting Operations. PSES Pollutant or pollutant property Maximum for...
Air Pollution Emissions Overview | Air Quality Planning & ...
2016-06-08
Air pollution comes from many different sources: stationary sources such as factories, power plants, and smelters and smaller sources such as dry cleaners and degreasing operations; mobile sources such as cars, buses, planes, trucks, and trains; and naturally occurring sources such as windblown dust, and volcanic eruptions, all contribute to air pollution.
NASA Astrophysics Data System (ADS)
Zhang, Shou-ping; Xin, Xiao-kang
2017-07-01
Identification of pollutant sources for river pollution incidents is an important and difficult task in the emergency rescue, and an intelligent optimization method can effectively compensate for the weakness of traditional methods. An intelligent model for pollutant source identification has been established using the basic genetic algorithm (BGA) as an optimization search tool and applying an analytic solution formula of one-dimensional unsteady water quality equation to construct the objective function. Experimental tests show that the identification model is effective and efficient: the model can accurately figure out the pollutant amounts or positions no matter single pollution source or multiple sources. Especially when the population size of BGA is set as 10, the computing results are sound agree with analytic results for a single source amount and position identification, the relative errors are no more than 5 %. For cases of multi-point sources and multi-variable, there are some errors in computing results for the reasons that there exist many possible combinations of the pollution sources. But, with the help of previous experience to narrow the search scope, the relative errors of the identification results are less than 5 %, which proves the established source identification model can be used to direct emergency responses.
A Monte Carlo approach to the inverse problem of diffuse pollution risk in agricultural catchments
NASA Astrophysics Data System (ADS)
Milledge, D.; Lane, S. N.; Heathwaite, A. L.; Reaney, S.
2012-04-01
The hydrological and biogeochemical processes that operate in catchments influence the ecological quality of freshwater systems through delivery of fine sediment, nutrients and organic matter. As an alternative to the, often complex, reductionist models we outline a - data-driven - approach based on 'inverse modelling'. We invert SCIMAP, a parsimonious risk based model that has an explicit treatment of hydrological connectivity, and use a Bayesian approach to determine the risk that must be assigned to different land uses in a catchment in order to explain the spatial patterns of measured in-stream nutrient concentrations. First, we apply the model to a set of eleven UK catchments to show that: 1) some land use generates a consistently high or low risk of diffuse nitrate (N) and Phosphate (P) pollution; but 2) the risks associated with different land uses vary both between catchments and between P and N delivery; and 3) that the dominant sources of P and N risk in the catchment are often a function of the spatial configuration of land uses. These results suggest that on a case by case basis, inverse modelling may be used to help prioritise the focus of interventions to reduce diffuse pollution risk for freshwater ecosystems. However, a key uncertainty in this approach is the extent to which it can recover the 'true' risks associated with a land cover given error in both the input parameters and equifinality in model outcomes. We test this using a set of synthetic scenarios in which the true risks can be pre-assigned then compared with those recovered from the inverse model. We use these scenarios to identify the number of simulations and observations required to optimize recovery of the true weights, then explore the conditions under which the inverse model becomes equifinal (hampering recovery of the true weights) We find that this is strongly dependent on the covariance in land covers between subcatchments, introducing the possibility that instream sampling could be designed or subsampled to maximize identifiability of the risks associated with a given land cover.
NASA Astrophysics Data System (ADS)
Mekonnen, M. M.; Hoekstra, A. Y. Y.
2014-12-01
We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.
Valdor, Paloma F; Gómez, Aina G; Puente, Araceli
2015-01-15
Diffuse pollution from oil spills is a widespread problem in port areas (as a result of fuel supply, navigation and loading/unloading activities). This article presents a method to assess the environmental risk of oil handling facilities in port areas. The method is based on (i) identification of environmental hazards, (ii) characterization of meteorological and oceanographic conditions, (iii) characterization of environmental risk scenarios, and (iv) assessment of environmental risk. The procedure has been tested by application to the Tarragona harbor. The results show that the method is capable of representing (i) specific local pollution cases (i.e., discriminating between products and quantities released by a discharge source), (ii) oceanographic and meteorological conditions (selecting a representative subset data), and (iii) potentially affected areas in probabilistic terms. Accordingly, it can inform the design of monitoring plans to study and control the environmental impact of these facilities, as well as the design of contingency plans. Copyright © 2014 Elsevier Ltd. All rights reserved.
Bateman, Ian; Agarwala, Matthew; Binner, Amy; Coombes, Emma; Day, Brett; Ferrini, Silvia; Fezzi, Carlo; Hutchins, Michael; Lovett, Andrew; Posen, Paulette
2016-10-01
We present an integrated model of the direct consequences of climate change on land use, and the indirect effects of induced land use change upon the natural environment. The model predicts climate-driven shifts in the profitability of alternative uses of agricultural land. Both the direct impact of climate change and the induced shift in land use patterns will cause secondary effects on the water environment, for which agriculture is the major source of diffuse pollution. We model the impact of changes in such pollution on riverine ecosystems showing that these will be spatially heterogeneous. Moreover, we consider further knock-on effects upon the recreational benefits derived from water environments, which we assess using revealed preference methods. This analysis permits a multi-layered examination of the economic consequences of climate change, assessing the sequence of impacts from climate change through farm gross margins, land use, water quality and recreation, both at the individual and catchment scale. Copyright © 2016 Elsevier Ltd. All rights reserved.
Understanding and influencing behaviour change by farmers to improve water quality.
Blackstock, K L; Ingram, J; Burton, R; Brown, K M; Slee, B
2010-11-01
Diffuse pollution from agriculture remains a significant challenge to many countries seeking to improve and protect their water environments. This paper reviews literature relating to the provision of information and advice as a mechanism to encourage farmers to mitigate diffuse pollution. The paper presents findings from a literature review on influencing farmer behaviour and synthesizes three main areas of literature: psychological and institutional theories of behaviour; shifts in the approach to delivery of advice (from knowledge transfer to knowledge exchange); and the increased interest in heterogeneous farming cultures. These three areas interconnect in helping to understand how best to influence farmer behaviour in order to mitigate diffuse pollution. They are, however, literatures that are rarely cited in the water management arena. The paper highlights the contribution of the 'cultural turn' taken by rural social scientists in helping to understand collective and individual voluntary behaviour. The paper explores how these literatures can contribute to the existing understanding of water management in the agricultural context, particularly: when farmers question the scientific evidence; when there are increased calls for collaborative planning and management; and when there is increased value placed on information as a business commodity. The paper also highlights where there are still gaps in knowledge that need to be filled by future research - possibly in partnership with farmers themselves. Whilst information and advice has long been seen as an important part of diffuse pollution control, increasing climate variability that will require farmers to practice adaptive management is likely to make these mechanisms even more important. Copyright © 2009 Elsevier B.V. All rights reserved.
POLLUTION PREVENTION TECHNOLOGY DIFFUSION INITIATIVE (TDI)
Although pollution prevention (P2) technologies save money and help prevent the release of toxic and hazardous wastes into the environment, many companies are reluctant to install new equipment or change the current processes. Some of the reluctance is initiated by lack of time a...
Anthropogenic nitrogen sources and exports in a village-scale catchment in Southeast China.
Cao, Wenzhi; Hong, Huasheng; Zhang, Yuzhen; Chen, Nengwang; Zeng, Yue; Wang, Weiping
2006-01-01
An experimental village-scale catchment was selected for investigation of nitrogen (N) sources and exports. The mean N application rate over the catchment was 350.2 kg N ha(-1), but this rate varied spatially and temporally. The N leaching loss rate varied from 8.1 to 52.7 kg N ha(-1) under different land use regimes. The average N leaching loss rate was 13.4 kg N ha(-1) over the whole catchment, representing about 3.8% of the total N inputs. The N export rate through stormflows was 28.8 kg N ha(-1), about 8.2% of the total N inputs. Seasonal patterns showed that 95% of N exports through stormflows occurred during July to September in 2002. Overall, the maximum riverine N exports were 12.1% of total N inputs and 15.5% of the inorganic fertilizer N applied. Understanding N sources and exports in a village-scale catchment can provide a knowledge base for amelioration of diffuse agricultural pollution.
Atmospheric CO2 capture by algae: Negative carbon dioxide emission path.
Moreira, Diana; Pires, José C M
2016-09-01
Carbon dioxide is one of the most important greenhouse gas, which concentration increase in the atmosphere is associated to climate change and global warming. Besides CO2 capture in large emission point sources, the capture of this pollutant from atmosphere may be required due to significant contribution of diffuse sources. The technologies that remove CO2 from atmosphere (creating a negative balance of CO2) are called negative emission technologies. Bioenergy with Carbon Capture and Storage may play an important role for CO2 mitigation. It represents the combination of bioenergy production and carbon capture and storage, keeping carbon dioxide in geological reservoirs. Algae have a high potential as the source of biomass, as they present high photosynthetic efficiencies and high biomass yields. Their biomass has a wide range of applications, which can improve the economic viability of the process. Thus, this paper aims to assess the atmospheric CO2 capture by algal cultures. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, S.; Tang, L.
2007-05-01
Panjiakou Reservoir is an important drinking water resource in Haihe River Basin, Hebei Province, People's Republic of China. The upstream watershed area is about 35,000 square kilometers. Recently, the water pollution in the reservoir is becoming more serious owing to the non-point pollution as well as point source pollution on the upstream watershed. To effectively manage the reservoir and watershed and develop a plan to reduce pollutant loads, the loading of non-point and point pollution and their distribution on the upstream watershed must be understood fully. The SWAT model is used to simulate the production and transportation of the non-point source pollutants in the upstream watershed of the Panjiakou Reservoir. The loadings of non-point source pollutants are calculated for different hydrologic years and the spatial and temporal characteristics of non-point source pollution are studied. The stream network and topographic characteristics of the stream network and sub-basins are all derived from the DEM by ArcGIS software. The soil and land use data are reclassified and the soil physical properties database file is created for the model. The SWAT model was calibrated with observed data of several hydrologic monitoring stations in the study area. The results of the calibration show that the model performs fairly well. Then the calibrated model was used to calculate the loadings of non-point source pollutants for a wet year, a normal year and a dry year respectively. The time and space distribution of flow, sediment and non-point source pollution were analyzed depending on the simulated results. The comparison of different hydrologic years on calculation results is dramatic. The loading of non-point source pollution in the wet year is relatively larger but smaller in the dry year since the non-point source pollutants are mainly transported through the runoff. The pollution loading within a year is mainly produced in the flood season. Because SWAT is a distributed model, it is possible to view model output as it varies across the basin, so the critical areas and reaches can be found in the study area. According to the simulation results, it is found that different land uses can yield different results and fertilization in rainy season has an important impact on the non- point source pollution. The limitations of the SWAT model are also discussed and the measures of the control and prevention of non- point source pollution for Panjiakou Reservoir are presented according to the analysis of model calculation results.
NASA Astrophysics Data System (ADS)
Su, Shiliang; Zhi, Junjun; Lou, Liping; Huang, Fang; Chen, Xia; Wu, Jiaping
Characterizing the spatio-temporal patterns and apportioning the pollution sources of water bodies are important for the management and protection of water resources. The main objective of this study is to describe the dynamics of water quality and provide references for improving river pollution control practices. Comprehensive application of neural-based modeling and different multivariate methods was used to evaluate the spatio-temporal patterns and source apportionment of pollution in Qiantang River, China. Measurement data were obtained and pretreated for 13 variables from 41 monitoring sites for the period of 2001-2004. A self-organizing map classified the 41 monitoring sites into three groups (Group A, B and C), representing different pollution characteristics. Four significant parameters (dissolved oxygen, biochemical oxygen demand, total phosphorus and total lead) were identified by discriminant analysis for distinguishing variations of different years, with about 80% correct assignment for temporal variation. Rotated principal component analysis (PCA) identified four potential pollution sources for Group A (domestic sewage and agricultural pollution, industrial wastewater pollution, mineral weathering, vehicle exhaust and sand mining), five for Group B (heavy metal pollution, agricultural runoff, vehicle exhaust and sand mining, mineral weathering, chemical plants discharge) and another five for Group C (vehicle exhaust and sand mining, chemical plants discharge, soil weathering, biochemical pollution, mineral weathering). The identified potential pollution sources explained 75.6% of the total variances for Group A, 75.0% for Group B and 80.0% for Group C, respectively. Receptor-based source apportionment was applied to further estimate source contributions for each pollution variable in the three groups, which facilitated and supported the PCA results. These results could assist managers to develop optimal strategies and determine priorities for river pollution control and effective water resources management.
Controlling Nonpoint-Source Water Pollution: A Citizen's Handbook.
ERIC Educational Resources Information Center
Hansen, Nancy Richardson; And Others
Citizens can play an important role in helping their states develop pollution control programs and spurring effective efforts to deal with nonpoint-source pollution. This guide takes the reader step-by-step through the process that states must follow to comply with water quality legislation relevant to nonpoint-source pollution. Part I provides…
40 CFR 420.94 - New source performance standards (NSPS).
Code of Federal Regulations, 2011 CFR
2011-07-01
....0 to 9.0. (5) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance... Within the range of 6.0 to 9.0. The above limitations shall be applicable to each fume scrubber....0 to 9.0. (4) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance...
40 CFR 420.94 - New source performance standards (NSPS).
Code of Federal Regulations, 2013 CFR
2013-07-01
....0 to 9.0. (5) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance... Within the range of 6.0 to 9.0. The above limitations shall be applicable to each fume scrubber....0 to 9.0. (4) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance...
40 CFR 420.94 - New source performance standards (NSPS).
Code of Federal Regulations, 2012 CFR
2012-07-01
....0 to 9.0. (5) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance... Within the range of 6.0 to 9.0. The above limitations shall be applicable to each fume scrubber....0 to 9.0. (4) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance...
40 CFR 420.94 - New source performance standards (NSPS).
Code of Federal Regulations, 2014 CFR
2014-07-01
....0 to 9.0. (5) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance... Within the range of 6.0 to 9.0. The above limitations shall be applicable to each fume scrubber....0 to 9.0. (4) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance...
40 CFR 420.94 - New source performance standards (NSPS).
Code of Federal Regulations, 2010 CFR
2010-07-01
....0 to 9.0. (5) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance... Within the range of 6.0 to 9.0. The above limitations shall be applicable to each fume scrubber....0 to 9.0. (4) Fume scrubbers. Subpart I Pollutant or pollutant property New source performance...
Identifying exposure disparities in air pollution epidemiology specific to adverse birth outcomes
NASA Astrophysics Data System (ADS)
Geer, Laura A.
2014-10-01
More than 147 million people in the US live in areas where pollutant levels are above regulatory limits and pose a risk to health. Most of the vast network of air pollutant monitors in the US are located in places with higher pollution levels and a higher density of pollutant sources (e.g., point sources from industrial pollution). Vulnerable populations are more likely to live closer to pollutant sources, and thus closer to pollutant monitors. These differential exposures have an impact on maternal and child health; maternal air pollutant exposures have been linked to adverse outcomes such as preterm birth and infant low birth weight. Several studies are highlighted that address methodological approaches in the study of air pollution and health disparities.
Fate of hydrocarbon pollutants in source and non-source control sustainable drainage systems.
Roinas, Georgios; Mant, Cath; Williams, John B
2014-01-01
Sustainable drainage (SuDs) is an established method for managing runoff from developments, and source control is part of accepted design philosophy. However, there are limited studies into the contribution source control makes to pollutant removal, especially for roads. This study examines organic pollutants, total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs), in paired source and non-source control full-scale SuDs systems. Sites were selected to cover local roads, trunk roads and housing developments, with a range of SuDs, including porous asphalt, swales, detention basins and ponds. Soil and water samples were taken bi-monthly over 12 months to assess pollutant loads. Results show first flush patterns in storm events for solids, but not for TPH. The patterns of removal for specific PAHs were also different, reflecting varying physico-chemical properties. The potential of trunk roads for pollution was illustrated by peak runoff for TPH of > 17,000 μg/l. Overall there was no significant difference between pollutant loads from source and non-source control systems, but the dynamic nature of runoff means that longer-term data are required. The outcomes of this project will increase understanding of organic pollutants behaviour in SuDs. This will provide design guidance about the most appropriate systems for treating these pollutants.
Kukučka, Petr; Audy, Ondřej; Kohoutek, Jiří; Holt, Eva; Kalábová, Tereza; Holoubek, Ivan; Klánová, Jana
2015-11-01
Riverine sediments, collected on a monthly basis during a period of one year, from five sites in a mixed land use region of the Czech Republic were analysed for chlorinated and brominated persistent organic pollutants (POPs). The region is located in the upper catchment of the Danube River. The POPs concentrations were as follows: 11-930 pg g(-1) polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs), 170-980 pg g(-1) dioxin-like polychlorinated biphenyls (dl-PCBs), 34-13,700 pg g(-1) polychlorinated naphthalenes (PCNs), 5.7-29,200 pg g(-1) polybrominated diphenylethers (PBDEs) and 0.21-351 ng g(-1) hexabromocyclododecanes (HBCDs). Concentrations expressed as toxic equivalents (TEQs), for PCDD/F+dl-PCB+PCN (TEQPCDD/F+dl-PCB+PCN) ranged from 0.37 to 19 pg g(-1). The results revealed a clear spatial separation between sites based on concentration and congener profile. There were also some obvious temporal patterns of selected POPs, which were related to river flow (seasonality) and organic carbon (TOC) of the sediment. Potential sources of POPs include local municipalities (flame retardants), some diffuse sources (PCNs and PCDDs/Fs) and potential point sources (PBDEs). Risk assessment based on risk quotients (RQ) revealed limited to medium ecological risk from PBDEs. TEQPCDD/F+dl-PCB+PCN were low relative to other European rivers, hence the risk to aquatic organisms was considered to be low. PCNs contributed significantly to overall TEQ in several cases. Copyright © 2015 Elsevier Ltd. All rights reserved.
Air born soil pollution assessment and mitigation in the south of ukraine
NASA Astrophysics Data System (ADS)
Titarenko, Olga; Kharytonov, Mykola; Moschner, Christin; Khlopova, Valentina M.
2016-04-01
Atmospheric emissions made by mining and metallurgy industry account for 54 % of total air pollutions of the Dnipropetrovsk Region. As it has been shown previously, the range of pollutants depends on the number and types of the industrial enterprises located within the each urban area. In Dnipropetrovsk and surrounding cities the dominant emissions come from the waste of metallurgical and chemical industries, which is heavily developed in this area. The multipollution exposure assessment was made for the several cities in Dnipropetrovsk industrial region in the south of Ukraine. In this connection the monitoring of atmospheric air pollution in the environment of the Dnepropetrovsk megalopolis area was carried out in several industrial cities: Dnipropetrovsk, Dneprodzerzhynsk, Kryvyy Ryg and Pavlograd with use of the network of stationary monitoring stations at the Dnepropetrovsk Regional Center of Hydrometeorology. The initial evaluation of technogenic atmospheric pollution with toxic substances was performed with due to the limit values of so-called maximum permissible concentrations (MPC) for harmful emissions in the atmosphere as set out in the Ukrainian Air Quality Standards. The main sources of air pollution in industrial cities are stationary. Meantime increasing road transport is a growing source of pollution. The maximum excess of MPC content of NO2 in the atmosphere of the cities has reached twice. Over the last 5 years in the atmosphere of industrial cities in the region there was an increased level of nitrogen dioxide (excess of MPC in 1, 5-2, 5 times). Number of inorganic aerosols (nitrogen dioxide, sulfur dioxide and other) has an effect of summation. In the presence of diffuse sources are superimposed individual emissions and formed the total torch actually located over the whole of the industrial agglomeration. Spatial structure of such a torch is very complicated, instant concentrations of impurities at various points in the city are substantially different. Summary torch formed over each industrial city from the merger of numerous enterprises emissions, under the influence of wind can spread in the long distances.The main sources of soil pollution in Pavlograd city and suburban territories are mine tailings, heat supply companies, operating in Western Donbass coal, other industrial enterprises and transport. The coal and mine rocks contain significant amounts of heavy metals and rare earth elements, lead, zinc, vanadium, manganese, cobalt, chromium, germanium, cerium and others. Settling on the earth's surface, they form insoluble compounds and accumulate in the upper parts of the soil cover. The detection of acid rain impact for the vast number of analyzed soil samples (95 %) were weakly acidic pH (6.3 - 6.8). As a result of consistent mapping of pollution in the city of Pavlograd six heavy metals was obtained corresponding GIS map. Follow to the analysis of the GIS map, it becomes possible to select multiple halos increased density of total soil contamination with heavy metals. The total pollution index of multipollution level of soil contamination was calculated for generalization of the obtained results. For most of the analyzed samples, according to the above gradation, the environmental situation of the contamination of soils by heavy metals is changed from "moderately threatening" to "threatening". The conception of step by step integrated approach using phytostabilization and phytoremediation measures has been completed. Some rocks as sorbents for detoxification of contaminated soils with heavy metals were studied. The coefficients of heavy metals accumulation for some crops were established in model experiments.
Solute source depletion control of forward and back diffusion through low-permeability zones
NASA Astrophysics Data System (ADS)
Yang, Minjune; Annable, Michael D.; Jawitz, James W.
2016-10-01
Solute diffusive exchange between low-permeability aquitards and high-permeability aquifers acts as a significant mediator of long-term contaminant fate. Aquifer contaminants diffuse into aquitards, but as contaminant sources are depleted, aquifer concentrations decline, triggering back diffusion from aquitards. The dynamics of the contaminant source depletion, or the source strength function, controls the timing of the transition of aquitards from sinks to sources. Here, we experimentally evaluate three archetypical transient source depletion models (step-change, linear, and exponential), and we use novel analytical solutions to accurately account for dynamic aquitard-aquifer diffusive transfer. Laboratory diffusion experiments were conducted using a well-controlled flow chamber to assess solute exchange between sand aquifer and kaolinite aquitard layers. Solute concentration profiles in the aquitard were measured in situ using electrical conductivity. Back diffusion was shown to begin earlier and produce larger mass flux for rapidly depleting sources. The analytical models showed very good correspondence with measured aquifer breakthrough curves and aquitard concentration profiles. The modeling approach links source dissolution and back diffusion, enabling assessment of human exposure risk and calculation of the back diffusion initiation time, as well as the resulting plume persistence.
Solute source depletion control of forward and back diffusion through low-permeability zones.
Yang, Minjune; Annable, Michael D; Jawitz, James W
2016-10-01
Solute diffusive exchange between low-permeability aquitards and high-permeability aquifers acts as a significant mediator of long-term contaminant fate. Aquifer contaminants diffuse into aquitards, but as contaminant sources are depleted, aquifer concentrations decline, triggering back diffusion from aquitards. The dynamics of the contaminant source depletion, or the source strength function, controls the timing of the transition of aquitards from sinks to sources. Here, we experimentally evaluate three archetypical transient source depletion models (step-change, linear, and exponential), and we use novel analytical solutions to accurately account for dynamic aquitard-aquifer diffusive transfer. Laboratory diffusion experiments were conducted using a well-controlled flow chamber to assess solute exchange between sand aquifer and kaolinite aquitard layers. Solute concentration profiles in the aquitard were measured in situ using electrical conductivity. Back diffusion was shown to begin earlier and produce larger mass flux for rapidly depleting sources. The analytical models showed very good correspondence with measured aquifer breakthrough curves and aquitard concentration profiles. The modeling approach links source dissolution and back diffusion, enabling assessment of human exposure risk and calculation of the back diffusion initiation time, as well as the resulting plume persistence. Copyright © 2016 Elsevier B.V. All rights reserved.
Effects of Climate Change on Diffuse Pollution in Lake Mogan Watershed
NASA Astrophysics Data System (ADS)
Alp, E.; Özcan, Z.
2017-12-01
Climate change is putting increasing pressure on water bodies. It can affect the behavior of pollutants in the environment and their interaction with the hydrological cycle. For instance, changing precipitation patterns may result in higher volumes of runoff containing numerous contaminants to water bodies and eventually loss of life-supporting function of them. The purpose of this study is to evaluate the impacts of climate change on diffuse pollution in Lake Mogan watershed located in a climate change vulnerable region and where agricultural diffuse pollution is one of the significant concerns. Lake Mogan watershed has an area of 970 km2 and it is dominated by dry agricultural practices and characterized by intermittent creeks. The lake was declared as a special environmental protection region in 1990. In this study, the impacts of climate change on diffuse pollution in the Lake Mogan watershed was evaluated using with a water quality model, SWAT (Soil and Water Assessment Tool). SWAT is a conceptual, continuous time model that operates on a daily time step. The model has been used in many studies to estimate the impacts of climate change, to calculate pollutant loads and to evaluate the best management practices all over the world. The required inputs for SWAT model can be categorized under the following basic categories: topography, land use/land cover, soil properties, land management practices occurring in the watershed, and meteorological inputs. According to Turkish Ministry of Forestry and Water Affairs (2016), it is estimated that the annual average temperature values will increase up to 3.3°C during the 85 year projection period as compared to reference period in the RCP4.5 scenario in the study area. This increase is predicted as up to 5.7°C based on the RCP8.5 scenario. The calibrated SWAT model for the Lake Mogan Watershed is used for the climate change scenarios for a period of 2010 and 2100. It is aimed that the outcomes of this study will help decision makers to develop beneficial management strategies so that the sustainable management of the specially protected water body is provided.
AGRICULTURAL NONPOINT SOURCE POLLUTION (AGNPS)
Developed by the USDA Agricultural Research Service, Agricultural Nonpoint Source Pollution (AGNPS) model addresses concerns related to the potential impacts of point and nonpoint source pollution on surface and groundwater quality (Young et al., 1989). It was designed to quantit...
40 CFR 49.135 - Rule for emissions detrimental to public health or welfare.
Code of Federal Regulations, 2013 CFR
2013-07-01
...? This section is intended to prevent the emission of air pollutants from any air pollution source... affected by this section? This section applies to any person who owns or operates an air pollution source. (c) What are the requirements for air pollution sources? (1) A person must not cause or allow the...
40 CFR 49.135 - Rule for emissions detrimental to public health or welfare.
Code of Federal Regulations, 2014 CFR
2014-07-01
...? This section is intended to prevent the emission of air pollutants from any air pollution source... affected by this section? This section applies to any person who owns or operates an air pollution source. (c) What are the requirements for air pollution sources? (1) A person must not cause or allow the...
40 CFR 49.135 - Rule for emissions detrimental to public health or welfare.
Code of Federal Regulations, 2012 CFR
2012-07-01
...? This section is intended to prevent the emission of air pollutants from any air pollution source... affected by this section? This section applies to any person who owns or operates an air pollution source. (c) What are the requirements for air pollution sources? (1) A person must not cause or allow the...
NASA Astrophysics Data System (ADS)
Karl, Matthias; Ramacher, Martin; Aulinger, Armin; Matthias, Volker; Quante, Markus
2017-04-01
Air quality modelling plays an important role by providing guidelines for efficient air pollution abatement measures. Currently, most urban dispersion models treat air pollutants as passive tracer substances or use highly simplified chemistry when simulating air pollutant concentrations on the city-scale. The newly developed urban chemistry-transport model CityChem has the capability of modelling the photochemical transformation of multiple pollutants along with atmospheric diffusion to produce pollutant concentration fields for the entire city on a horizontal resolution of 100 m or even finer and a vertical resolution of 24 layers up to 4000 m height. CityChem is based on the Eulerian urban dispersion model EPISODE of the Norwegian Institute for Air Research (NILU). CityChem treats the complex photochemistry in cities using detailed EMEP chemistry on an Eulerian 3-D grid, while using simple photo-stationary equilibrium on a much higher resolution grid (receptor grid), i.e. close to industrial point sources and traffic sources. The CityChem model takes into account that long-range transport contributes to urban pollutant concentrations. This is done by using 3-D boundary concentrations for the city domain derived from chemistry-transport simulations with the regional air quality model CMAQ. For the study of the air quality in Hamburg, CityChem was set-up with a main grid of 30×30 grid cells of 1×1 km2 each and a receptor grid of 300×300 grid cells of 100×100 m2. The CityChem model was driven with meteorological data generated by the prognostic meteorology component of the Australian chemistry-transport model TAPM. Bottom-up inventories of emissions from traffic, industry, households were based on data of the municipality of Hamburg. Shipping emissions for the port of Hamburg were taken from the Clean North Sea Shipping project. Episodes with elevated ozone (O3) were of specific interest for this study, as these are associated with exceedances of the World Health Organization (WHO) guideline concentration limits for O3 and of the regulatory limits for NO2. Model tests were performed with CityChem to study the ozone formation rate with simultaneous variation of emissions of nitrogen oxides (NOx) and volatile organic compounds (VOC). Emissions of VOC in urban areas are not well quantified as they may originate from various sources, including solvent usage, industry, combustion plants and vehicular traffic. The employed chemical mechanism contains large uncertainties with respect to ozone formation. Observed high-O3 episodes were analyzed by comparing modelled pollutant concentrations with concentration data from the Hamburg air quality surveillance network (http://luft.hamburg.de/). The analysis inspected possible reasons for too low modelled O3 in summer such as missing emissions of VOC from natural sources like green parks and the vertical exchange of O3 towards the surface.
[Nitrogen non-point source pollution identification based on ArcSWAT in Changle River].
Deng, Ou-Ping; Sun, Si-Yang; Lü, Jun
2013-04-01
The ArcSWAT (Soil and Water Assessment Tool) model was adopted for Non-point source (NPS) nitrogen pollution modeling and nitrogen source apportionment for the Changle River watershed, a typical agricultural watershed in Southeast China. Water quality and hydrological parameters were monitored, and the watershed natural conditions (including soil, climate, land use, etc) and pollution sources information were also investigated and collected for SWAT database. The ArcSWAT model was established in the Changle River after the calibrating and validating procedures of the model parameters. Based on the validated SWAT model, the contributions of different nitrogen sources to river TN loading were quantified, and spatial-temporal distributions of NPS nitrogen export to rivers were addressed. The results showed that in the Changle River watershed, Nitrogen fertilizer, nitrogen air deposition and nitrogen soil pool were the prominent pollution sources, which contributed 35%, 32% and 25% to the river TN loading, respectively. There were spatial-temporal variations in the critical sources for NPS TN export to the river. Natural sources, such as soil nitrogen pool and atmospheric nitrogen deposition, should be targeted as the critical sources for river TN pollution during the rainy seasons. Chemical nitrogen fertilizer application should be targeted as the critical sources for river TN pollution during the crop growing season. Chemical nitrogen fertilizer application, soil nitrogen pool and atmospheric nitrogen deposition were the main sources for TN exported from the garden plot, forest and residential land, respectively. However, they were the main sources for TN exported both from the upland and paddy field. These results revealed that NPS pollution controlling rules should focus on the spatio-temporal distribution of NPS pollution sources.
Polluted Runoff: Nonpoint Source Pollution
Nonpoint Source (NPS) pollution is caused by rainfall or snowmelt moving over and through the ground, it picks up and carries natural and human-made pollutants, depositing them into lakes, rivers, wetlands, coastal waters and ground waters.
NASA Astrophysics Data System (ADS)
Quattrocchi, Fedora; Vaccaro, Carmela; Boschi, Enzo
2014-05-01
Smart grids-Smat cities "fashion" requires management plans of highly urbanized areas located over the Padanian floodplain, which are prone to diffuse pollution of both lands and urban sectors, mostly after the disasters caused by tremendous alluvial rains in January 2014, when shallow aquifers and agricultural matters could have increase pollution over wide territory. Moreover the urban expansion has affected areas previously used for industrial activity and in some cases such for landfills. When the loss of memory of previous activity prevails after urbanization, with health issues, ethical questions are inevitable, accompanied by social conflicts and economic impacts. The alluvial plains of active tectonic areas - as the Padania Valley - in additions to widespread "anthropogenic pollution" is suffering from widespread "natural pollution" of deep fluid sources - mainly methane - corresponding to areas prone to uprising gaseous brines, along faults. Some of them were partially activated during the 2012 Emilia seismic sequence. This noteworthy seismic sequence engaged discussion about the possible role of gas storages and hydrocarbons production or the simple/exploring drilling activity to trigger typical tectonic seismicity. The paper deepen this troubled communication strategy, their gaps and peculiar geopolicy case histories, to avoid the same strategy, in the future. On the other hand, gas burst or brine-gas-contamination in shallow aquifers, soils and indoor, should be studied by simple and cheap methods, by deepening stratigraphic gaps for the tectonics effects on sedimentation: natural processes should be recalled prior to recall anthropogenic causes, if any. Policy should be more responsible in state clearly the role of research in study infrastructures/processes, also when engaged by private companies, for sites selected by ministries mostly to star research: relevant gaps involves serious confusion in the public as regards responsibility and an exact reconstruction of the true facts. Moreover these areas are affected by natural enrichment in heavy metals and toxic elements harmful to the health: geochemical surveying may allow both to recognize issues of diffuse "natural pollution" and to identify markers and tracers able to discriminate among anthropogenic and natural anomalies by geochemical methods mostly. The discovery of pollution emergency poses the problem of how to share to the public scientific data, avoiding that communication produces alarmism or persecution for the involved researchers, as occurred in the past. When diffuse pollution is linked to natural causes which can be defined as transient that precede potential gas-burst disasters, the risk communication by researchers not always meets sufficient support from those who are responsible for the administration of the territory, being afraid to lose the political consensus. Conflicts of interest in promoting certain non urgent research should be highlighted readily and clearly. This is one of the main cause of low resources devoted to the study of transient geochemical contamination in shallow aquifers, which could be useful for seismotectonic research too. A discussion about: i) intellectual property & equal opportunity for all Earth Science researchers to have access to the public research calls (MIUR, MATT MSE Ministries); ii) about the critical research on some short-term hazards, which penalized the researchers in terms of scientific productivity and career was opened by the paper, suggesting new research evaluation indicators -ethical ones- than Impact Factor only.
Modeling Nitrogen Fate and Transport at the Sediment-Water Interface
Diffusive mass transfer at media interfaces exerts control on the fate and transport of pollutants originating from agricultural and urban landscapes and affects the con-ditions of water bodies. Diffusion is essentially a physical process affecting the distribution and fate of va...
Yang, Liping; Mei, Kun; Liu, Xingmei; Wu, Laosheng; Zhang, Minghua; Xu, Jianming; Wang, Fan
2013-08-01
Water quality degradation in river systems has caused great concerns all over the world. Identifying the spatial distribution and sources of water pollutants is the very first step for efficient water quality management. A set of water samples collected bimonthly at 12 monitoring sites in 2009 and 2010 were analyzed to determine the spatial distribution of critical parameters and to apportion the sources of pollutants in Wen-Rui-Tang (WRT) river watershed, near the East China Sea. The 12 monitoring sites were divided into three administrative zones of urban, suburban, and rural zones considering differences in land use and population density. Multivariate statistical methods [one-way analysis of variance, principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) methods] were used to investigate the spatial distribution of water quality and to apportion the pollution sources. Results showed that most water quality parameters had no significant difference between the urban and suburban zones, whereas these two zones showed worse water quality than the rural zone. Based on PCA and APCS-MLR analysis, urban domestic sewage and commercial/service pollution, suburban domestic sewage along with fluorine point source pollution, and agricultural nonpoint source pollution with rural domestic sewage pollution were identified to the main pollution sources in urban, suburban, and rural zones, respectively. Understanding the water pollution characteristics of different administrative zones could put insights into effective water management policy-making especially in the area across various administrative zones.
NASA Astrophysics Data System (ADS)
Salvadó, Joan A.; Grimalt, Joan O.; López, Jordi F.; Durrieu de Madron, Xavier; Pasqual, Catalina; Canals, Miquel
2013-11-01
Superficial sediments from Cap de Creus to the Rhone Delta, in the Gulf of Lion, Northwestern Mediterranean Sea, including the mid-shelf mud belt and the continental slope were collected between 2005 and 2008 to assess the levels, main sources and distribution patterns of organochlorine pollutants. Discharges from the Rhone River are the main source for all these compounds around the area. The spatial distribution of organochlorine pollutants was also related to their physicochemical properties and to sediment grain size and composition. The concentrations of polychlorobiphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDD and DDE), and the chlorobenzenes (CBzs) - pentachlorobenzene (PeCB) and hexachlorobenzene (HCB) - decreased westwards along the mid-shelf mud belt. In contrast, hexachlorocyclohexane isomers (HCHs), namely lindane (γ-HCH), followed another concentration pattern suggesting a different transport mode. The major concentrations of organochlorine compounds were observed off the Rhone River mouth, in the prodelta, where PCB, DDT and CBz concentrations reached 38, 29 and 8.3 ng g-1, respectively. These average concentrations in the mid continental shelf were two to ten times lower than those found in a study performed about 20 years ago, albeit in almost all the sites the values of PCBs and DDTs still exceed the NOAA’s Sediment Quality Guidelines. In contrast, the concentrations in the continental slope were nearly the same as 20 years ago, which may evidence that even most of these compounds were banned decades ago, their background concentrations associated to diffuse pollution have not decreased in the deep continental margin.
Porter, Kenneth D H; Reaney, Sim M; Quilliam, Richard S; Burgess, Chris; Oliver, David M
2017-12-31
Microbial pollution of surface waters in agricultural catchments can be a consequence of poor farm management practices, such as excessive stocking of livestock on vulnerable land or inappropriate handling of manures and slurries. Catchment interventions such as fencing of watercourses, streamside buffer strips and constructed wetlands have the potential to reduce faecal pollution of watercourses. However these interventions are expensive and occupy valuable productive land. There is, therefore, a requirement for tools to assist in the spatial targeting of such interventions to areas where they will have the biggest impact on water quality improvements whist occupying the minimal amount of productive land. SCIMAP is a risk-based model that has been developed for this purpose but with a focus on diffuse sediment and nutrient pollution. In this study we investigated the performance of SCIMAP in predicting microbial pollution of watercourses and assessed modelled outputs of E. coli, a common faecal indicator organism (FIO), against observed water quality information. SCIMAP was applied to two river catchments in the UK. SCIMAP uses land cover risk weightings, which are routed through the landscape based on hydrological connectivity to generate catchment scale maps of relative in-stream pollution risk. Assessment of the model's performance and derivation of optimum land cover risk weightings was achieved using a Monte-Carlo sampling approach. Performance of the SCIMAP framework for informing on FIO risk was variable with better performance in the Yealm catchment (r s =0.88; p<0.01) than the Wyre (r s =-0.36; p>0.05). Across both catchments much uncertainty was associated with the application of optimum risk weightings attributed to different land use classes. Overall, SCIMAP showed potential as a useful tool in the spatial targeting of FIO diffuse pollution management strategies; however, improvements are required to transition the existing SCIMAP framework to a robust FIO risk-mapping tool. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
[Study on the risk assessment method of regional groundwater pollution].
Yang, Yan; Yu, Yun-Jiang; Wang, Zong-Qing; Li, Ding-Long; Sun, Hong-Wei
2013-02-01
Based on the boundary elements of system risk assessment, the regional groundwater pollution risk assessment index system was preliminarily established, which included: regional groundwater specific vulnerability assessment, the regional pollution sources characteristics assessment and the health risk assessment of regional featured pollutants. The three sub-evaluation systems were coupled with the multi-index comprehensive method, the risk was characterized with the Spatial Analysis of ArcMap, and a new method to evaluate regional groundwater pollution risk that suitable for different parts of natural conditions, different types of pollution was established. Take Changzhou as an example, the risk of shallow groundwater pollution was studied with the new method, and found that the vulnerability index of groundwater in Changzhou is high and distributes unevenly; The distribution of pollution sources is concentrated and has a great impact on groundwater pollution risks; Influenced by the pollutants and pollution sources, the values of health risks are high in the urban area of Changzhou. The pollution risk of shallow groundwater is high and distributes unevenly, and distributes in the north of the line of Anjia-Xuejia-Zhenglu, the center of the city and the southeast, where the human activities are more intense and the pollution sources are intensive.
NASA Astrophysics Data System (ADS)
Zhang, Weihong.; Zhao, Yongsheng; Hong, Mei; Guo, Xiaodong
2009-04-01
Groundwater pollution usually is complex and concealed, remediation of which is difficult, high cost, time-consuming, and ineffective. An early warning system for groundwater pollution is needed that detects groundwater quality problems and gets the information necessary to make sound decisions before massive groundwater quality degradation occurs. Groundwater pollution early warning were performed by considering comprehensively the current groundwater quality, groundwater quality varying trend and groundwater pollution risk . The map of the basic quality of the groundwater was obtained by fuzzy comprehensive evaluation or BP neural network evaluation. Based on multi-annual groundwater monitoring datasets, Water quality state in sometime of the future was forecasted using time-sequenced analyzing methods. Water quality varying trend was analyzed by Spearman's rank correlative coefficient.The relative risk map of groundwater pollution was estimated through a procedure that identifies, cell by cell,the values of three factors, that is inherent vulnerability, load risk of pollution source and contamination hazard. DRASTIC method was used to assess inherent vulnerability of aquifer. Load risk of pollution source was analyzed based on the potential of contamination and pollution degree. Assessment index of load risk of pollution source which involves the variety of pollution source, quantity of contaminants, releasing potential of pollutants, and distance were determined. The load risks of all sources considered by GIS overlay technology. Early warning model of groundwater pollution combined with ComGIS technology organically, the regional groundwater pollution early-warning information system was developed, and applied it into Qiqiha'er groundwater early warning. It can be used to evaluate current water quality, to forecast water quality changing trend, and to analyze space-time influencing range of groundwater quality by natural process and human activities. Keywords: groundwater pollution, early warning, aquifer vulnerability, pollution load, pollution risk, ComGIS
Inversion of Atmospheric Tracer Measurements, Localization of Sources
NASA Astrophysics Data System (ADS)
Issartel, J.-P.; Cabrit, B.; Hourdin, F.; Idelkadi, A.
When abnormal concentrations of a pollutant are observed in the atmosphere, the question of its origin arises immediately. The radioactivity from Tchernobyl was de- tected in Sweden before the accident was announced. This situation emphasizes the psychological, political and medical stakes of a rapid identification of sources. In tech- nical terms, most industrial sources can be modeled as a fixed point at ground level with undetermined duration. The classical method of identification involves the cal- culation of a backtrajectory departing from the detector with an upstream integration of the wind field. We were first involved in such questions as we evaluated the ef- ficiency of the international monitoring network planned in the frame of the Com- prehensive Test Ban Treaty. We propose a new approach of backtracking based upon the use of retroplumes associated to available measurements. Firstly the retroplume is related to inverse transport processes, describing quantitatively how the air in a sam- ple originates from regions that are all the more extended and diffuse as we go back far in the past. Secondly it clarifies the sensibility of the measurement with respect to all potential sources. It is therefore calculated by adjoint equations including of course diffusive processes. Thirdly, the statistical interpretation, valid as far as sin- gle particles are concerned, should not be used to investigate the position and date of a macroscopic source. In that case, the retroplume rather induces a straightforward constraint between the intensity of the source and its position. When more than one measurements are available, including zero valued measurements, the source satisfies the same number of linear relations tightly related to the retroplumes. This system of linear relations can be handled through the simplex algorithm in order to make the above intensity-position correlation more restrictive. This method enables to manage in a quantitative manner the unavoidable ambiguity of atmospheric phenomena. When several measurements are available the ambiguity about the identification of a source is reduced significantly.
40 CFR 49.138 - Rule for the registration of air pollution sources and the reporting of emissions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... following air pollutants: particulate matter, PM10, PM2.5, sulfur oxides (SOX), nitrogen oxides (NOX... from air pollution sources: (i) Source-specific emission tests; (ii) Mass balance calculations; (iii...
40 CFR 49.138 - Rule for the registration of air pollution sources and the reporting of emissions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... following air pollutants: particulate matter, PM10, PM2.5, sulfur oxides (SOX), nitrogen oxides (NOX... from air pollution sources: (i) Source-specific emission tests; (ii) Mass balance calculations; (iii...
40 CFR 49.138 - Rule for the registration of air pollution sources and the reporting of emissions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... following air pollutants: particulate matter, PM10, PM2.5, sulfur oxides (SOX), nitrogen oxides (NOX... from air pollution sources: (i) Source-specific emission tests; (ii) Mass balance calculations; (iii...
40 CFR 49.138 - Rule for the registration of air pollution sources and the reporting of emissions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... following air pollutants: particulate matter, PM10, PM2.5, sulfur oxides (SOX), nitrogen oxides (NOX... from air pollution sources: (i) Source-specific emission tests; (ii) Mass balance calculations; (iii...
We compared various in vitro exposure systems for their ability to expose cells to particles and gases. The systems tested use different mechanisms to deliver multi-pollutants to the cells: diffusion, sedimentation, thermophoresis (THP) and electrostatic precipitation (ESP). Vari...
REPRESENTATION OF ATMOSPHERIC MOTION IN MODELS OF REGIONAL-SCALE AIR POLLUTION
A method is developed for generating ensembles of wind fields for use in regional scale (1000 km) models of transport and diffusion. The underlying objective is a methodology for representing atmospheric motion in applied air pollution models that permits explicit treatment of th...
NASA Astrophysics Data System (ADS)
Vardoulakis, Sotiris; Solazzo, Efisio; Lumbreras, Julio
2011-09-01
Automatic monitoring networks have the ability of capturing air pollution episodes, as well as short- and long-term air quality trends in urban areas that can be used in epidemiological studies. However, due to practical constraints (e.g. cost and bulk of equipment), the use of automatic analysers is restricted to a limited number of roadside and background locations within a city. As a result, certain localised air pollution hotspots may be overlooked or overemphasised, especially near heavily trafficked street canyons and intersections. This has implications for compliance with regulatory standards and may cause exposure misclassification in epidemiological studies. Apart from automatic analysers, low cost passive diffusion tubes can be used to characterise the spatial variability of air pollution in urban areas. In this study, BTEX, NO 2 and O 3 data from a one-year passive sampling survey were used to characterise the intra-urban and street scale spatial variability of traffic-related pollutants in Birmingham (UK). In addition, continuous monitoring of NO 2, NO x, O 3, CO, SO 2, PM 10 and PM 2.5 from three permanent monitoring sites was used to identify seasonal and annual pollution patterns. The passive sampling measurements allowed us to evaluate the representativeness of a permanent roadside monitoring site that has recorded some of the highest NO 2 and PM 10 concentrations in Birmingham in recent years. Dispersion modelling was also used to gain further insight into pollutant sources and dispersion characteristics at this location. The strong spatial concentration gradients observed in busy streets, as well as the differences between roadside and urban background levels highlight the importance of appropriate positioning of air quality monitoring equipment in cities.
Microplastic pollution in the surface waters of Italian Subalpine Lakes.
Sighicelli, Maria; Pietrelli, Loris; Lecce, Francesca; Iannilli, Valentina; Falconieri, Mauro; Coscia, Lucia; Di Vito, Stefania; Nuglio, Simone; Zampetti, Giorgio
2018-05-01
Plastic debris incidence in marine environment was already highlighted in the early 1970s. Over the last decade, microplastic pollution in the environment has received increasing attention and is now an emerging research area. Many studies have focused on quantifying microplastic abundance in the marine environment, while there are relatively few data on microplastic occurrence in freshwater environment. Recent studies have reported high concentrations of microplastics in lakes and rivers, although the understanding of several factors influencing source, transport and fate is still limited. This study compares different lakes and the common factors, which could influence the occurrence and distribution of microplastics. The three subalpine lakes monitored include Lake Maggiore, Iseo and Garda. The selected sampling transects reflect the hydrologic conditions, the morphometric characteristics of these lakes, and other factors influencing the release of plastics debris in lakes. Particles of microplastics (<5 mm) were found in all sampled surfaces. The particles collected were classified depending on their number, shape and composition. The shape distribution showed the dominating occurrence of fragments (73.7%). The chemical composition of all examined samples clearly shows dominating presence of polyethylene (45%), polystyrene (18%) and polypropylene (15%). The results provide significant relations among the different contribution of direct and diffuse sources to the quantity of microplastics, highlighting the importance of understanding the spatial distribution dynamics of microplastics within a lake system that acts as a sink and source of plastic particles. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Quinton, John; Stevens, Carly
2010-05-01
Pollution swapping occurs when a mitigation option introduced to reduce one pollutant results in an increase in a different pollutant. Although the concept of pollution swapping is widely understood it has received little attention in research and policy design. This study investigated diffuse pollution mitigation options applied in combinable crop systems. They are: cover crops, residue management, no-tillage, riparian buffer zones, contour grass strips and constructed wetlands. A wide range of water and atmospheric pollutants were considered, including nitrogen, phosphorus, carbon and sulphur. It is clear from this investigation that there is no single mitigation option that will reduce all pollutants and in this poster we consider how choices may be made between mitigation measures which may have a positive effect on one pollutant but a negative effect on another.
NASA Astrophysics Data System (ADS)
Malsy, Marcus; Reder, Klara; Flörke, Martina
2014-05-01
Decreasing water quality is one of the main global issues which poses risks to food security, economy, and public health and is consequently crucial for ensuring environmental sustainability. During the last decades access to clean drinking water increased, but 2.5 billion people still do not have access to basic sanitation, especially in Africa and parts of Asia. In this context not only connection to sewage system is of high importance, but also treatment, as an increasing connection rate will lead to higher loadings and therefore higher pressure on water resources. Furthermore, poor people in developing countries use local surface waters for daily activities, e.g. bathing and washing. It is thus clear that water utilization and water sewerage are indispensable connected. In this study, large scale water quality modelling is used to point out hotspots of water pollution to get an insight on potential environmental impacts, in particular, in regions with a low observation density and data gaps in measured water quality parameters. We applied the global water quality model WorldQual to calculate biological oxygen demand (BOD) loadings from point and diffuse sources, as well as in-stream concentrations. Regional focus in this study is on developing countries i.e. Africa, Asia, and South America, as they are most affected by water pollution. Hereby, model runs were conducted for the year 2010 to draw a picture of recent status of surface waters quality and to figure out hotspots and main causes of pollution. First results show that hotspots mainly occur in highly agglomerated regions where population density is high. Large urban areas are initially loading hotspots and pollution prevention and control become increasingly important as point sources are subject to connection rates and treatment levels. Furthermore, river discharge plays a crucial role due to dilution potential, especially in terms of seasonal variability. Highly varying shares of BOD sources across regions, and across sectors demand for an integrated approach to assess main causes of water quality degradation.
NASA Astrophysics Data System (ADS)
Ward, Ray; Purnell, Sarah; Ebdon, James; Nnane, Daniel; Taylor, Huw
2013-04-01
The Water Framework Directive (WFD) regulates surface water quality standards in the European Union (EU). The Directive call for the identification and management of point and diffuse sources of pollution and requires the establishment of a 'programme of measures' for identified river basin districts, in order to achieve a "good status" by 2015. The hygienic quality of water is normally monitored using faecal indicator organisms (FIO), such as Escherichia coli, which indicate a potential risk to public health from human waterborne pathogens. Environmental factors influence the transmission of these pathogens and indicator organisms, and statistically significant relationships have been found between rainfall and outbreaks of waterborne disease. Climate change has been predicted to lead to an increase in severe weather events in many parts of Europe, including an increase in the frequency of extreme rainfall events. This in turn is likely to lead to an increase in incidents of human waterborne disease in Europe, unless measures are taken to predict and mitigate for such events. This study investigates a variety of environmental factors that influence the concentration of FIO in surface waters receiving faecal contamination from a variety of sources. Levels of FIO, including Escherichia coli, intestinal enterococci, somatic coliphage and GB124 (a human-specific microbial source tracking marker), were monitored in the Sussex Ouse catchment in Southeast England over a period of 26 months. These data were combined with geoinformatic environmental data within a GIS to map faecal contamination within the river. Previously, precipitation and soil erosion have been identified as major factors that can influence the concentration of these faecal markers, and studies have shown that slope, soil type and vegetation influence both the mechanisms and the rate by which erosion occurs in river catchments. Of the environmental variables studied, extreme precipitation was found to be a major factor contributing to increased levels of FIO. This study identifies areas within the catchment that are likely to demonstrate elevated erosion rates during extreme precipitation events, which are likely to result in raised levels of FIO. The results also demonstrate that increases in the human faecal marker were associated with the discharge points of wastewater treatment works, and that levels of the marker increased whenever the works discharged untreated wastewaters during extreme precipitation. Spatial analysis also highlighted locations where human faecal pollution was present in areas away from wastewater treatment plants, highlighting the potential significance of inputs from septic tanks and other un-sewered domestic wastewater systems. Increases in the frequency of extreme precipitation events in many parts of Europe are likely to result in increased levels of water pollution from both point- and diffuse-sources, increasing the input of pathogens into surface waters, and elevating the health risks to downstream consumers of abstracted drinking water. This study suggests an approach that integrates water microbiology and geoinformatic data to support a 'prediction and prevention' approach, in place of the traditional focus on water quality monitoring. This work may therefore make a significant contribution to future European water resource management and health protection.
USDA-ARS?s Scientific Manuscript database
Emission factors are used in the air pollution regulatory process to quantify the mass of pollutants emitted from a source. Accurate emission factors must be used in the air pollution regulatory process to ensure fair and appropriate regulation for all sources. Agricultural sources, including cotton...
Lohmann, Rainer; Jaward, Foday M; Durham, Louise; Barber, Jonathan L; Ockenden, Wendy; Jones, Kevin C; Bruhn, Regina; Lakaschus, Soenke; Dachs, Jordi; Booij, Kees
2004-07-15
Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.
Nitrous acid formation in a snow-free wintertime polluted rural area
NASA Astrophysics Data System (ADS)
Tsai, Catalina; Spolaor, Max; Fedele Colosimo, Santo; Pikelnaya, Olga; Cheung, Ross; Williams, Eric; Gilman, Jessica B.; Lerner, Brian M.; Zamora, Robert J.; Warneke, Carsten; Roberts, James M.; Ahmadov, Ravan; de Gouw, Joost; Bates, Timothy; Quinn, Patricia K.; Stutz, Jochen
2018-02-01
Nitrous acid (HONO) photolysis is an important source of hydroxyl radicals (OH) in the lower atmosphere, in particular in winter when other OH sources are less efficient. The nighttime formation of HONO and its photolysis in the early morning have long been recognized as an important contributor to the OH budget in polluted environments. Over the past few decades it has become clear that the formation of HONO during the day is an even larger contributor to the OH budget and additionally provides a pathway to recycle NOx. Despite the recognition of this unidentified HONO daytime source, the precise chemical mechanism remains elusive. A number of mechanisms have been proposed, including gas-phase, aerosol, and ground surface processes, to explain the elevated levels of daytime HONO. To identify the likely HONO formation mechanisms in a wintertime polluted rural environment we present LP-DOAS observations of HONO, NO2, and O3 on three absorption paths that cover altitude intervals from 2 to 31, 45, and 68 m above ground level (a.g.l.) during the UBWOS 2012 experiment in the Uintah Basin, Utah, USA. Daytime HONO mixing ratios in the 2-31 m height interval were, on average, 78 ppt, which is lower than HONO levels measured in most polluted urban environments with similar NO2 mixing ratios of 1-2 ppb. HONO surface fluxes at 19 m a.g.l., calculated using the HONO gradients from the LP-DOAS and measured eddy diffusivity coefficient, show clear upward fluxes. The hourly average vertical HONO flux during sunny days followed solar irradiance, with a maximum of (4.9 ± 0.2) × 1010 molec. cm-2 s-1 at noontime. A photostationary state analysis of the HONO budget shows that the surface flux closes the HONO budget, accounting for 63 ± 32 % of the unidentified HONO daytime source throughout the day and 90 ± 30 % near noontime. This is also supported by 1-D chemistry and transport model calculations that include the measured surface flux, thus clearly identifying chemistry at the ground as the missing daytime HONO source in this environment. Comparison between HONO surface flux, solar radiation, NO2 and HNO3 mixing ratios, and results from 1-D model runs suggest that, under high NOx conditions, HONO formation mechanisms related to solar radiation and NO2 mixing ratios, such as photo-enhanced conversion of NO2 on the ground, are most likely the source of daytime HONO. Under moderate to low NO2 conditions, photolysis of HNO3 on the ground seems to be the main source of HONO.
Xu, Hua-Shan; Xu, Zong-Xue; Liu, Pin
2013-03-01
One of the key techniques in establishing and implementing TMDL (total maximum daily load) is to utilize hydrological model to quantify non-point source pollutant loads, establish BMPs scenarios, reduce non-point source pollutant loads. Non-point source pollutant loads under different years (wet, normal and dry year) were estimated by using SWAT model in the Zhangweinan River basin, spatial distribution characteristics of non-point source pollutant loads were analyzed on the basis of the simulation result. During wet years, total nitrogen (TN) and total phosphorus (TP) accounted for 0.07% and 27.24% of the total non-point source pollutant loads, respectively. Spatially, agricultural and residential land with steep slope are the regions that contribute more non-point source pollutant loads in the basin. Compared to non-point source pollutant loads with those during the baseline period, 47 BMPs scenarios were set to simulate the reduction efficiency of different BMPs scenarios for 5 kinds of pollutants (organic nitrogen, organic phosphorus, nitrate nitrogen, dissolved phosphorus and mineral phosphorus) in 8 prior controlled subbasins. Constructing vegetation type ditch was optimized as the best measure to reduce TN and TP by comparing cost-effective relationship among different BMPs scenarios, and the costs of unit pollutant reduction are 16.11-151.28 yuan x kg(-1) for TN, and 100-862.77 yuan x kg(-1) for TP, which is the most cost-effective measure among the 47 BMPs scenarios. The results could provide a scientific basis and technical support for environmental protection and sustainable utilization of water resources in the Zhangweinan River basin.
40 CFR 421.195 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Indium Subcategory Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Indium... existing sources. The mass of wastewater pollutants in secondary indium process wastewater introduced into...
40 CFR 421.195 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Indium Subcategory Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Indium... existing sources. The mass of wastewater pollutants in secondary indium process wastewater introduced into...
IDENTIFICATION OF SOURCES OF FECAL POLLUTION IN ENVIRONMENTAL WATERS
A number of Microbial Source Tracking (MST) methods are currently used to determine the origin of fecal pollution impacting environmental waters. MST is based on the assumption that given the appropriate method and indicator organism, the source of fecal microbial pollution can ...
Khuzestani, Reza Bashiri; Schauer, James J; Shang, Jing; Cai, Tianqi; Fang, Dongqing; Wei, Yongjie; Zhang, Lulu; Zhang, Yuanxun
2018-05-01
The Ordos region in the southwestern part of Inner Mongolia experiences frequent PM concentrations in excess of the national PM 2.5 air quality standards. In order to determine the key sources of PM 2.5 contributing to these pollution episodes, the main sources of PM 2.5 OC during elevated PM episodes in the Inner Mongolia were analyzed and compared with non-polluted days. This will provide insight to the main sources of particulate matter pollution during the high-pollution episodes and the effective seasonal strategies to control sources of particulate matter during months and with the highest PM concentrations that need to be controlled. The PMF source contributions to OC demonstrated that the industrial/coal combustion (4762.77 ± 1061.54 versus 2726.49 ± 469.75 ng/m 3 ; p < 0.001) and mobile source factors (4651.14 ± 681.82 versus 2605.55 ± 276.50 ng/m 3 ; p value < 0.001) showed greater contributions to the elevated concentrations during the episode. The spatial analysis of secondary organic carbon (SOC) factors, regional biomass burning, and biogenic sources did not show significant difference in the pollution episodes and the non-polluted months. In addition, the bivariate polar plots and CWT maps of the industrial/coal combustion and mobile illustrated a regional long-range transport patterns from the external sources to the study area, however, adjacent areas were mostly controlling the contributions of these factors during the PM elevated episodes. The SOC sources, regional biomass burning, and biogenic sources illustrated a regional long-range transport with similar locations found during the elevated pollution episodes compared to the normal situations.
Annotated Bibliography of Law-Related Pollution Prevention Sources.
ERIC Educational Resources Information Center
Lynch, Holly; Murphy, Elaine
This annotated bibliography of law-related pollution prevention sources was prepared by the National Pollution Prevention Center for Higher Education. Some topics of the items include waste reduction, hazardous wastes, risk reduction, environmental policy, pollution prevention, environmental protection, environmental leadership, environmental…
EPA Air Pollution Control Cost Manual
EPA's Air Pollution Control Cost Manual provides guidance for the development of accurate and consistent costs for air pollution control devices. A long-standing document prepared by EPA, the Control Cost Manual focuses on point source and stationary area source air pollution con...
Wu, Yiping; Chen, Ji
2013-01-01
Understanding the physical processes of point source (PS) and nonpoint source (NPS) pollution is critical to evaluate river water quality and identify major pollutant sources in a watershed. In this study, we used the physically-based hydrological/water quality model, Soil and Water Assessment Tool, to investigate the influence of PS and NPS pollution on the water quality of the East River (Dongjiang in Chinese) in southern China. Our results indicate that NPS pollution was the dominant contribution (>94%) to nutrient loads except for mineral phosphorus (50%). A comprehensive Water Quality Index (WQI) computed using eight key water quality variables demonstrates that water quality is better upstream than downstream despite the higher level of ammonium nitrogen found in upstream waters. Also, the temporal (seasonal) and spatial distributions of nutrient loads clearly indicate the critical time period (from late dry season to early wet season) and pollution source areas within the basin (middle and downstream agricultural lands), which resource managers can use to accomplish substantial reduction of NPS pollutant loadings. Overall, this study helps our understanding of the relationship between human activities and pollutant loads and further contributes to decision support for local watershed managers to protect water quality in this region. In particular, the methods presented such as integrating WQI with watershed modeling and identifying the critical time period and pollutions source areas can be valuable for other researchers worldwide.
Recent Approaches to Estimate Associations Between Source-Specific Air Pollution and Health.
Krall, Jenna R; Strickland, Matthew J
2017-03-01
Estimating health effects associated with source-specific exposure is important for better understanding how pollution impacts health and for developing policies to better protect public health. Although epidemiologic studies of sources can be informative, these studies are challenging to conduct because source-specific exposures (e.g., particulate matter from vehicles) often are not directly observed and must be estimated. We reviewed recent studies that estimated associations between pollution sources and health to identify methodological developments designed to address important challenges. Notable advances in epidemiologic studies of sources include approaches for (1) propagating uncertainty in source estimation into health effect estimates, (2) assessing regional and seasonal variability in emissions sources and source-specific health effects, and (3) addressing potential confounding in estimated health effects. Novel methodological approaches to address challenges in studies of pollution sources, particularly evaluation of source-specific health effects, are important for determining how source-specific exposure impacts health.
Study on road surface source pollution controlled by permeable pavement
NASA Astrophysics Data System (ADS)
Zheng, Chaocheng
2018-06-01
The increase of impermeable pavement in urban construction not only increases the runoff of the pavement, but also produces a large number of Non-Point Source Pollution. In the process of controlling road surface runoff by permeable pavement, a large number of particulate matter will be withheld when rainwater is being infiltrated, so as to control the source pollution at the source. In this experiment, we determined the effect of permeable road surface to remove heavy pollutants in the laboratory and discussed the related factors that affect the non-point pollution of permeable pavement, so as to provide a theoretical basis for the application of permeable pavement.
Development of unauthorized airborne emission source identification procedure
NASA Astrophysics Data System (ADS)
Shtripling, L. O.; Bazhenov, V. V.; Varakina, N. S.; Kupriyanova, N. P.
2018-01-01
The paper presents the procedure for searching sources of unauthorized airborne emissions. To make reasonable regulation decisions on airborne pollutant emissions and to ensure the environmental safety of population, the procedure provides for the determination of a pollutant mass emission value from the source being the cause of high pollution level and the search of a previously unrecognized contamination source in a specified area. To determine the true value of mass emission from the source, the minimum of the mean-root-square mismatch criterion between the computed and measured pollutant concentration in the given location is used.
40 CFR 421.275 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth... standards for existing sources. The mass of wastewater pollutants in primary rare earth metals process.... PSES for the Primary Rare Earth Metals Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.275 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth... standards for existing sources. The mass of wastewater pollutants in primary rare earth metals process.... PSES for the Primary Rare Earth Metals Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.275 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth... standards for existing sources. The mass of wastewater pollutants in primary rare earth metals process.... PSES for the Primary Rare Earth Metals Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.275 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth... standards for existing sources. The mass of wastewater pollutants in primary rare earth metals process.... PSES for the Primary Rare Earth Metals Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.275 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth... standards for existing sources. The mass of wastewater pollutants in primary rare earth metals process.... PSES for the Primary Rare Earth Metals Subcategory Pollutant or pollutant property Maximum for any 1...
ERIC Educational Resources Information Center
Barton, Kathy
1978-01-01
Nonpoint source pollution, water pollution not released at one specific identifiable point, now accounts for 50 percent of the nation's water pollution problem. Runoff is the primary culprit and includes the following sources: agriculture, mining, hydrologic modifications, and urban runoff. Economics, legislation, practices, and management of this…
Simultaneous Exposure to Multiple Air Pollutants Influences Alveolar Epithelial Cell Ion Transport
Purpose. Air pollution sources generally release multiple pollutants simultaneously and yet, research has historically focused on the source-to-health linkages of individual air pollutants. We recently showed that exposure of alveolar epithelial cells to a combination of particul...
Ma, Junjie; Meng, Fansheng; Zhou, Yuexi; Wang, Yeyao; Shi, Ping
2018-02-16
Pollution accidents that occur in surface waters, especially in drinking water source areas, greatly threaten the urban water supply system. During water pollution source localization, there are complicated pollutant spreading conditions and pollutant concentrations vary in a wide range. This paper provides a scalable total solution, investigating a distributed localization method in wireless sensor networks equipped with mobile ultraviolet-visible (UV-visible) spectrometer probes. A wireless sensor network is defined for water quality monitoring, where unmanned surface vehicles and buoys serve as mobile and stationary nodes, respectively. Both types of nodes carry UV-visible spectrometer probes to acquire in-situ multiple water quality parameter measurements, in which a self-adaptive optical path mechanism is designed to flexibly adjust the measurement range. A novel distributed algorithm, called Dual-PSO, is proposed to search for the water pollution source, where one particle swarm optimization (PSO) procedure computes the water quality multi-parameter measurements on each node, utilizing UV-visible absorption spectra, and another one finds the global solution of the pollution source position, regarding mobile nodes as particles. Besides, this algorithm uses entropy to dynamically recognize the most sensitive parameter during searching. Experimental results demonstrate that online multi-parameter monitoring of a drinking water source area with a wide dynamic range is achieved by this wireless sensor network and water pollution sources are localized efficiently with low-cost mobile node paths.
Zhou, Yuexi; Wang, Yeyao; Shi, Ping
2018-01-01
Pollution accidents that occur in surface waters, especially in drinking water source areas, greatly threaten the urban water supply system. During water pollution source localization, there are complicated pollutant spreading conditions and pollutant concentrations vary in a wide range. This paper provides a scalable total solution, investigating a distributed localization method in wireless sensor networks equipped with mobile ultraviolet-visible (UV-visible) spectrometer probes. A wireless sensor network is defined for water quality monitoring, where unmanned surface vehicles and buoys serve as mobile and stationary nodes, respectively. Both types of nodes carry UV-visible spectrometer probes to acquire in-situ multiple water quality parameter measurements, in which a self-adaptive optical path mechanism is designed to flexibly adjust the measurement range. A novel distributed algorithm, called Dual-PSO, is proposed to search for the water pollution source, where one particle swarm optimization (PSO) procedure computes the water quality multi-parameter measurements on each node, utilizing UV-visible absorption spectra, and another one finds the global solution of the pollution source position, regarding mobile nodes as particles. Besides, this algorithm uses entropy to dynamically recognize the most sensitive parameter during searching. Experimental results demonstrate that online multi-parameter monitoring of a drinking water source area with a wide dynamic range is achieved by this wireless sensor network and water pollution sources are localized efficiently with low-cost mobile node paths. PMID:29462929
Elçi, A; Karadaş, D; Fistikoğlu, O
2010-01-01
A numerical modeling case study of groundwater flow in a diffuse pollution prone area is presented. The study area is located within the metropolitan borders of the city of Izmir, Turkey. This groundwater flow model was unconventional in the application since the groundwater recharge parameter in the model was estimated using a lumped, transient water-budget based precipitation-runoff model that was executed independent of the groundwater flow model. The recharge rate obtained from the calibrated precipitation-runoff model was used as input to the groundwater flow model, which was eventually calibrated to measured water table elevations. Overall, the flow model results were consistent with field observations and model statistics were satisfactory. Water budget results of the model revealed that groundwater recharge comprised about 20% of the total water input for the entire study area. Recharge was the second largest component in the budget after leakage from streams into the subsurface. It was concluded that the modeling results can be further used as input for contaminant transport modeling studies in order to evaluate the vulnerability of water resources of the study area to diffuse pollution.
Peng, Jianfeng; Song, Yonghui; Yuan, Peng; Xiao, Shuhu; Han, Lu
2013-07-01
The chemical industry is a major source of various pollution accidents. Improving the management level of risk sources for pollution accidents has become an urgent demand for most industrialized countries. In pollution accidents, the released chemicals harm the receptors to some extent depending on their sensitivity or susceptibility. Therefore, identifying the potential risk sources from such a large number of chemical enterprises has become pressingly urgent. Based on the simulation of the whole accident process, a novel and expandable identification method for risk sources causing water pollution accidents is presented. The newly developed approach, by analyzing and stimulating the whole process of a pollution accident between sources and receptors, can be applied to identify risk sources, especially on the nationwide scale. Three major types of losses, such as social, economic and ecological losses, were normalized, analyzed and used for overall consequence modeling. A specific case study area, located in a chemical industry park (CIP) along the Yangtze River in Jiangsu Province, China, was selected to test the potential of the identification method. The results showed that there were four risk sources for pollution accidents in this CIP. Aniline leakage in the HS Chemical Plant would lead to the most serious impact on the surrounding water environment. This potential accident would severely damage the ecosystem up to 3.8 km downstream of Yangtze River, and lead to pollution over a distance stretching to 73.7 km downstream. The proposed method is easily extended to the nationwide identification of potential risk sources.
NASA Astrophysics Data System (ADS)
Malaj, Naim; Ammoscato, Ivano; Andreoli, Virginia; Bencardino, Mariantonia; Cofone, Franco; Cosentino, Ugo; Mannarino, Valentino; Piazzalunga, Andrea; Pirrone, Nicola; Pitea, Demetrio; Servidio, Alessandro; Vardè, Massimiliano; Sprovieri, Francesca
2015-04-01
The almost unique geographic position as well as meteo-climatic characteristics of the Mediterranean basin surrounded by several anthropogenic and natural pollution sources, delineate it as one of the most polluted area. The intense maritime traffic and the industries of developed countries bordering the basin have been indicated as the major impact factors amongst the anthropogenic pollution sources while biomass burning, volcanoes fumes and frequent Saharan dust events represent the principal pollution coming from natural fonts. Land generated pollutants transported via air masses into marine atmosphere exert their impact on aquatic ecosystem, air quality and global climate. Although land-based air pollution monitoring sites are diffused through the Mediterranean countries, those regarding the atmospheric aerosol measured directly at sea surface are limited, leading to a scarce availability of the information. In order to fill this gap and to have more insights into the atmospheric dynamical and chemical mechanisms leading to high surface aerosol levels, the Institute of Atmospheric Pollution of the National Research Council (CNR-IIA) has started regular ship borne measurements over the Mediterranean Sea since 20001. In this context, here we report the results obtained during two cruise campaigns performed in two distinct routs and periods: i) Urania 2011 made within the Tyrrhenian Sea during the fall season, and ii) Urania 2012 performed during summer within the Eastern sector of the Mediterranean sea basin. Fine (PM2.5) and coarse (PM2.5-10) particles were collected on PTFE membrane filters (Advantec MFS) and their mass concentrations were determined gravimetrically. Successively, all the filters were digested with a mixture of HNO3/H2O2 in an open vessel digestion system (DigiPrep-MS, SCP SCIENCE, Canada) and analyzed by ICP-MS for the determination of the following elements: Be, Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sb, Ba, Tl, Pb, Th, and U. The method was previously optimized and assessed for suitable recovery levels (100 ± 15) on NIST SRM-1648a Urban Particulate Matter. Results regarding the mass concentration (PM2.5 and PM2.5-10), the content and the distribution of the analyzed elements over both PM fractions will be discussed taking into account different meteorological and sampling conditions. References M. Bencardino, N. Pirrone and F. Sprovieri, Environ. Sci. Pollut. Res., 2014, 21:4044-4062.
40 CFR 428.96 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Pan, Dry Digestion, and Mechanical... pollutant properties, controlled by this section, which may be discharged to a publicly owned treatment works by a new point source subject to the provisions of this subpart: Pollutant or pollutant property...
40 CFR 421.186 - Pretreatment standards for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Germanium and Gallium Subcategory § 421.186 Pretreatment standards for new sources. Except as provided in 40... sources. The mass of wastewater pollutants in primary and secondary germanium and gallium process... Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.186 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Germanium and Gallium Subcategory § 421.186 Pretreatment standards for new sources. Except as provided in 40... sources. The mass of wastewater pollutants in primary and secondary germanium and gallium process... Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.186 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Germanium and Gallium Subcategory § 421.186 Pretreatment standards for new sources. Except as provided in 40... sources. The mass of wastewater pollutants in primary and secondary germanium and gallium process... Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.186 - Pretreatment standards for new sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Germanium and Gallium Subcategory § 421.186 Pretreatment standards for new sources. Except as provided in 40... sources. The mass of wastewater pollutants in primary and secondary germanium and gallium process... Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 421.186 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Germanium and Gallium Subcategory § 421.186 Pretreatment standards for new sources. Except as provided in 40... sources. The mass of wastewater pollutants in primary and secondary germanium and gallium process... Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant property Maximum for any 1...
40 CFR 461.44 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche Subcategory § 461... existing sources listed below: (1) Subpart D—Foliar Battery Miscellaneous Wash—PSES. Pollutant or pollutant... 0.015 (b) There shall be no discharge allowance for process wastewater pollutants from any battery...
40 CFR 461.44 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche Subcategory § 461... existing sources listed below: (1) Subpart D—Foliar Battery Miscellaneous Wash—PSES. Pollutant or pollutant... 0.015 (b) There shall be no discharge allowance for process wastewater pollutants from any battery...
Epelde, Lur; Martín-Sánchez, Iker; González-Oreja, José A; Anza, Mikel; Gómez-Sagasti, María T; Garbisu, Carlos
2012-09-01
Soils are currently being degraded at an alarming rate due to increasing pressure from different sources of environmental degradation. Consequently, we carried out a 4-month microcosm experiment to measure the impact of different sources of environmental degradation (biodiversity loss, nitrogen deposition and climate change) on soil health in a non-polluted (non-degraded) and a heavily metal-polluted (degraded) soil, and to compare their responses. To this aim, we determined a variety of soil microbial properties with potential as bioindicators of soil health: basal respiration; β-glucosaminidase and protease activities; abundance (Q-PCR) of bacterial, fungal and chitinase genes; richness (PCR-DGGE) of fungal and chitinase genes. Non-polluted and metal-polluted soils showed different response microbial dynamics when subjected to sources of environmental degradation. The non-polluted soil appeared resilient to "biodiversity loss" and "climate change" treatments. The metal-polluted soil was probably already too severely affected by the presence of high levels of toxic metals to respond to other sources of stress. Our data together suggests that soil microbial activity and biomass parameters are more sensitive to the applied sources of environmental degradation, showing immediate responses of greater magnitude, while soil microbial diversity parameters do not show such variations. Copyright © 2012 Elsevier B.V. All rights reserved.
Mass fluxes of organic pollutants between groundwater, streambed sediments and surface water
NASA Astrophysics Data System (ADS)
Schirmer, Mario; Kalbus, Edda; Schmidt, Christian
2010-05-01
Rivers and groundwater are commonly hydraulically connected and thus also pollutants migrate between one and the other. Particularly in small lowland streams, pollutant transport by discharging groundwater can deteriorate the surface water quality. Moreover, in urban and industrial areas streambed sediments are often polluted with a variety of organic and inorganic substances. For planning measures to improve surface water quality or to mitigate pollutant migration, it is an essential prerequisite to understand pollutant pathways and mass fluxes between the stream, the streambed sediment and the connected aquifer. We present methodological approaches and results of a study conducted at a small man-made stream located in the industrial area of Bitterfeld-Wolfen, Germany. This site is characterized by a diffuse groundwater contamination with a variety of aliphatic and aromatic organic substances. The underlying approach of this study was to quantify the mass fluxes between the aquifer, the streambed and the stream by combining high-resolution with integral monitoring approaches. Magnitudes and pattern of water fluxes were obtained by mapping streambed temperatures. The method was applied to a reach of 280 m in length. The mass fluxes from the aquifer towards the stream were estimated by combining the water fluxes with representative, average pollutant concentrations. The concentrations were obtained from an integral pumping test with four simultaneously pumped wells operated for the period of five days. For monochlorobenzene (MCB), the main groundwater pollutant at the site, the resulting average mass flux from the aquifer towards the stream was estimated to 724 µg/m²/d. Mass flux calculations with average aqueous concentrations of MCB in the streambed were found to be higher than those originating from the aquifer. Consequently, the streambed sediments represent a secondary pollutant source for the surface water. Pollutant concentrations in the streambed were lower at locations with high groundwater discharge and vice versa. Hence, the spatial heterogeneity of water fluxes must be considered when mass fluxes between surface water and streambed sediments are assessed. River restoration could improve the structural state of rivers and may thus result in an enhanced biodegradation of organic pollutants in the streambed. However, before any physical measure is applied a profound knowledge of pollutant concentration and pathways is required in order to avoid mobilization of sediment-bound pollutants.
Simulation of tracer dispersion from elevated and surface releases in complex terrain
NASA Astrophysics Data System (ADS)
Hernández, J. F.; Cremades, L.; Baldasano, J. M.
A new version of an advanced mesoscale dispersion modeling system for simulating passive air pollutant dispersion in the real atmospheric planetary boundary layer (PBL), is presented. The system comprises a diagnostic mass-consistent meteorological model and a Lagrangian particle dispersion model (LADISMO). The former version of LADISMO, developed according to Zannetti (Air pollution modelling, 1990), was based on the Monte Carlo technique and included calculation of higher-order moments of vertical random forcing for convective conditions. Its ability to simulate complex flow dispersion has been stated in a previous paper (Hernández et al. 1995, Atmospheric Environment, 29A, 1331-1341). The new version follows Thomson's scheme (1984, Q. Jl Roy. Met. Soc.110, 1107-1120). It is also based on Langevin equation and follows the ideas given by Brusasca et al. (1992, Atmospheric Environment26A, 707-723) and Anfossi et al. (1992, Nuovo Cemento 15c, 139-158). The model is used to simulate the dispersion and predict the ground level concentration (g.l.c.) of a tracer (SF 6) released from both an elevated source ( case a) and a ground level source ( case b) in a highly complex mountainous terrain during neutral and synoptically dominated conditions ( case a) and light and apparently stable conditions ( case b). The last case is considered as being a specially difficult task to simulate. In fact, few works have reported situations with valley drainage flows in complex terrains and real stable atmospheric conditions with weak winds. The model assumes that nearly calm situations associated to strong stability and air stagnation, make the lowest layers of PBL poorly diffusive (Brusasca et al., 1992, Atmospheric Environment26A, 707-723). Model results are verified against experimental data from Guardo-90 tracer experiments, an intensive field campaign conducted in the Carrion river valley (Northern Spain) to study atmospheric diffusion within a steep walled valley in mountainous terrain (Ibarra, 1992, Energia, No. 1, 74-85).
NASA Astrophysics Data System (ADS)
Dong, Feifei; Liu, Yong; Wu, Zhen; Chen, Yihui; Guo, Huaicheng
2018-07-01
Targeting nonpoint source (NPS) pollution hot spots is of vital importance for placement of best management practices (BMPs). Although physically-based watershed models have been widely used to estimate nutrient emissions, connections between nutrient abatement and compliance of water quality standards have been rarely considered in NPS hotspot ranking, which may lead to ineffective decision-making. It's critical to develop a strategy to identify priority management areas (PMAs) based on water quality response to nutrient load mitigation. A water quality constrained PMA identification framework was thereby proposed in this study, based on the simulation-optimization approach with ideal load reduction (ILR-SO). It integrates the physically-based Soil and Water Assessment Tool (SWAT) model and an optimization model under constraints of site-specific water quality standards. To our knowledge, it was the first effort to identify PMAs with simulation-based optimization. The SWAT model was established to simulate temporal and spatial nutrient loading and evaluate effectiveness of pollution mitigation. A metamodel was trained to establish a quantitative relationship between sources and water quality. Ranking of priority areas is based on required nutrient load reduction in each sub-watershed targeting to satisfy water quality standards in waterbodies, which was calculated with genetic algorithm (GA). The proposed approach was used for identification of PMAs on the basis of diffuse total phosphorus (TP) in Lake Dianchi Watershed, one of the three most eutrophic large lakes in China. The modeling results demonstrated that 85% of diffuse TP came from 30% of the watershed area. Compared with the two conventional targeting strategies based on overland nutrient loss and instream nutrient loading, the ILR-SO model identified distinct PMAs and narrowed down the coverage of management areas. This study addressed the urgent need to incorporate water quality response into PMA identification and showed that the ILR-SO approach is effective to guide watershed management for aquatic ecosystem restoration.
NASA Astrophysics Data System (ADS)
Li, Jiayun; Tong, Juxiu; Xia, Chuanan; Hu, Bill X.; Zhu, Hao; Yang, Rui; Wei, Wenshuo
2017-06-01
It has been widely recognized that surface runoff from agricultural field is an important non-point pollution source, which however, the chemical transfer amount in the process is very difficult to be quantified in field since some variables and natural factors are hard to control, such as rainfall intensity, temperature, wind speeds and soil spatial heterogeneity, which may significantly affect the field experimental results. Therefore, a physically based nitrogen transport model was developed and tested with the so called semi-field experiments (i.e., artificial rainfall was used instead of natural rainfall, but other conditions were natural) in this paper. Our model integrated the raindrop driven process and diffusion effect with the simplified nitrogen chain reactions. In this model, chemicals in the soil surface layer, or the 'exchange layer', were transformed into the surface runoff layer due to raindrop impact. The raindrops also have a significant role on the diffusion process between the exchange layer and the underlying soil. The established mathematical model was solved numerically through the modified Hydrus-1d source code, and the model simulations agreed well with the experimental data. The modeling results indicate that the depth of the exchange layer and raindrop induced water transfer rate are two important parameters for the simulation results. Variation of the water transfer rate, er, can strongly influence the peak values of the NO-3-N and NH+4-N concentration breakthrough curves. The concentration of NO-3-N is more sensitive to the exchange layer depth, de, than NH+4-N. In general, the developed model well describes the nitrogen loss into surface runoff in a raindrop driven process. Since the raindrop splash erosion process may aggravate the loss of chemical fertilizer, choosing an appropriate fertilization time and application method is very important to prevent the pollution.
40 CFR 430.45 - New source performance standards (NSPS).
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS THE PULP, PAPER, AND PAPERBOARD POINT SOURCE CATEGORY Dissolving Sulfite Subcategory... dissolving sulfite pulp facilities where nitration grade pulp is produced] Pollutant or pollutant property Kg... dissolving sulfite pulp facilities where viscose grade pulp is produced] Pollutant or pollutant property Kg...
CHARACTERIZATION OF INDOOR AND OUTDOOR AIR POLLUTION EXPOSURES AND SOURCES
Human exposures to indoor and outdoor pollutants vary depending on the sources and concentrations of pollutants as well as human behavioral factors that determine the extent of an individual's contact with indoor or outdoor pollutants. In general, the older populations spend more...
Environment and T regulatory cells in allergy.
Braga, M; Schiavone, C; Di Gioacchino, G; De Angelis, I; Cavallucci, E; Lazzarin, F; Petrarca, C; Di Gioacchino, M
2012-04-15
The central role of T regulatory cells in the responses against harmless environmental antigens has been confirmed by many studies. Impaired T regulatory cell function is implicated in many pathological conditions, particularly allergic diseases. The "hygiene hypothesis" suggests that infections and infestations may play a protective role for allergy, whereas environmental pollutants favor the development of allergic diseases. Developing countries suffer from a variety of infections and are also facing an increasing diffusion of environmental pollutants. In these countries allergies increase in relation to the spreading use of xenobiotics (pesticides, herbicides, pollution, etc.) with a rate similar to those of developed countries, overcoming the protective effects of infections. We review here the main mechanisms of non-self tolerance, with particular regard to relations between T regulatory cell activity, infections and infestations such as helminthiasis, and exposure to environmental xenobiotics with relevant diffusion in developing countries. Copyright © 2010 Elsevier B.V. All rights reserved.
Methods for reducing pollutant emissions from jet aircraft
NASA Technical Reports Server (NTRS)
Butze, H. F.
1971-01-01
Pollutant emissions from jet aircraft and combustion research aimed at reducing these emissions are defined. The problem of smoke formation and results achieved in smoke reduction from commercial combustors are discussed. Expermental results of parametric tests performed on both conventional and experimental combustors over a range of combustor-inlet conditions are presented. Combustor design techniques for reducing pollutant emissions are discussed. Improved fuel atomization resulting from the use of air-assist fuel nozzles has brought about significant reductions in hydrocarbon and carbon monoxide emissions at idle. Diffuser tests have shown that the combustor-inlet airflow profile can be controlled through the use of diffuser-wall bleed and that it may thus be possible to reduce emissions by controlling combustor airflow distribution. Emissions of nitric oxide from a shortlength annular swirl-can combustor were significantly lower than those from a conventional combustor operating at similar conditions.
Wu, Qiong; Qi, Jun; Xia, Xinghui
2017-12-31
Two dated sediment cores from the Miyun Reservoir of Beijing in China were analyzed to reconstruct the pollution history of heavy metals including cadmium (Cd), chromium (Cr), iron (Fe), nickel (Ni), and zinc (Zn) as well as phosphorus (P). Enrichment factor (EF) and geoaccumulation index (I geo ) were applied to assess the enrichment status of heavy metals. Average EF and I geo values indicated that the studied heavy metals in the sediments mainly originated from non-point source pollution and soil-water erosion, showing low ecological risks. In addition, correlation analysis and principal component analysis (PCA) identified that Cd, Zn, and P were mainly from agricultural diffusion pollution caused by utilization of the phosphate fertilizer; Zn, Ni, and Cr originated from soil erosion. PCA analysis was further conducted to investigate the relationships among meteorological factors, algae-dominant total organic carbon (TOC), and heavy metals. Results showed that algae-dominant TOC had strong positive correlation with temperature, which can be explained by that increased temperature accelerated the growth of algae. Meanwhile the opposite loadings between algae-dominant TOC and heavy metal suggested that primary production played an important role in migration and transformation of metals. Moreover, stepwise multiple regression models showed that Fe was sensitive to temperature, which accounted for approximately 39.0% and 40.1% of the variations in Fe of two sediment cores, respectively. Fe showed significant decreasing trends during the past 50years. Reductive environment of water-sediment interface caused by increasing temperature probably contributed to the restoration of ferric iron, resulting in the release of soluble Fe to overlying waters. Future climate change with elevated temperature and extreme weather events will aggravate the ecological risk of heavy metals in water environment due to the enhanced leaching effect and non-point source pollution as well as the release of heavy metals from sediments to water environment. Copyright © 2017. Published by Elsevier B.V.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-25
.... On February 12, 2010, the American Chemistry Council and the Society of Chemical Manufacturers and... National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources AGENCY... Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources (CMAS) that was...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-14
.... 40 CFR 63.11494(e). On February 12, 2010, the American Chemistry Council and the Society of Chemical... Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources AGENCY... Hazardous Air Pollutants for Chemical Manufacturing Area Sources. Among the provisions that EPA is...
Air Pollution, Causes and Cures.
ERIC Educational Resources Information Center
Manufacturing Chemists Association, Washington, DC.
This commentary on sources of air pollution and air purification treatments is accompanied by graphic illustrations. Sources of carbon monoxide, sulfur oxides, nitrogen oxides, and hydrocarbons found in the air are discussed. Methods of removing these pollutants at their source are presented with cut-away diagrams of the facilities and technical…
40 CFR 464.15 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Aluminum Casting... existing sources. (a) Casting Cleaning Operations. PSES Pollutant or pollutant property Maximum for any 1....0771 0.0421 Lead (T) 0.0791 0.039 Zinc (T) 0.114 0.0431 (b) Casting Quench Operation. PSES Pollutant or...
Air Pollution Manual, Part 1--Evaluation. Second Edition.
ERIC Educational Resources Information Center
Giever, Paul M., Ed.
Due to the great increase in technical knowledge and improvement in procedures, this second edition has been prepared to update existing information. Air pollution legislation is reviewed. Sources of air pollution are examined extensively. They are treated in terms of natural sources, man-made sources, metropolitan regional emissions, emission…
Nonpoint source pollution is the primary stress in many streams. Characteristic declines in stream fish communities are recognized in streams influenced by nonpoint source pollution, but the processes by which these declines occur are not well understood. Here, predicted time s...
NASA Astrophysics Data System (ADS)
Kostyuchenko, Yuriy V.; Sztoyka, Yulia; Kopachevsky, Ivan; Artemenko, Igor; Yuschenko, Maxim
2017-10-01
Multi-model approach for remote sensing data processing and interpretation is described. The problem of satellite data utilization in multi-modeling approach for socio-ecological risks assessment is formally defined. Observation, measurement and modeling data utilization method in the framework of multi-model approach is described. Methodology and models of risk assessment in framework of decision support approach are defined and described. Method of water quality assessment using satellite observation data is described. Method is based on analysis of spectral reflectance of aquifers. Spectral signatures of freshwater bodies and offshores are analyzed. Correlations between spectral reflectance, pollutions and selected water quality parameters are analyzed and quantified. Data of MODIS, MISR, AIRS and Landsat sensors received in 2002-2014 have been utilized verified by in-field spectrometry and lab measurements. Fuzzy logic based approach for decision support in field of water quality degradation risk is discussed. Decision on water quality category is making based on fuzzy algorithm using limited set of uncertain parameters. Data from satellite observations, field measurements and modeling is utilizing in the framework of the approach proposed. It is shown that this algorithm allows estimate water quality degradation rate and pollution risks. Problems of construction of spatial and temporal distribution of calculated parameters, as well as a problem of data regularization are discussed. Using proposed approach, maps of surface water pollution risk from point and diffuse sources are calculated and discussed.
NASA Astrophysics Data System (ADS)
Abou Rafee, Sameh A.; Martins, Leila D.; Kawashima, Ana B.; Almeida, Daniela S.; Morais, Marcos V. B.; Souza, Rita V. A.; Oliveira, Maria B. L.; Souza, Rodrigo A. F.; Medeiros, Adan S. S.; Urbina, Viviana; Freitas, Edmilson D.; Martin, Scot T.; Martins, Jorge A.
2017-06-01
This paper evaluates the contributions of the emissions from mobile, stationary and biogenic sources on air pollution in the Amazon rainforest by using the Weather Research and Forecasting with Chemistry (WRF-Chem) model. The analyzed air pollutants were CO, NOx, SO2, O3, PM2. 5, PM10 and volatile organic compounds (VOCs). Five scenarios were defined in order to evaluate the emissions by biogenic, mobile and stationary sources, as well as a future scenario to assess the potential air quality impact of doubled anthropogenic emissions. The stationary sources explain the highest concentrations for all air pollutants evaluated, except for CO, for which the mobile sources are predominant. The anthropogenic sources considered resulted an increasing in the spatial peak-temporal average concentrations of pollutants in 3 to 2780 times in relation to those with only biogenic sources. The future scenario showed an increase in the range of 3 to 62 % in average concentrations and 45 to 109 % in peak concentrations depending on the pollutant. In addition, the spatial distributions of the scenarios has shown that the air pollution plume from the city of Manaus is predominantly transported west and southwest, and it can reach hundreds of kilometers in length.
Xu, Yongfeng; Dai, Shixiang; Meng, Ke; Wang, Yuting; Ren, Wenjie; Zhao, Ling; Christie, Peter; Teng, Ying
2018-07-15
The residual levels and risk assessment of several potentially toxic elements (PTEs), phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in rural soils near different types of pollution sources in Tianjin, China, were studied. The soils were found to be polluted to different extents with PTEs, PAEs and PAHs from different pollution sources. The soil concentrations of chromium (Cr), nickel (Ni), di-n-butyl phthalate (DnBP), acenaphthylene (Any) and acenaphthene (Ane) were higher than their corresponding regulatory reference limits. The health risk assessment model used to calculate human exposure indicates that both non-carcinogenic and carcinogenic risks from selected pollutants were generally acceptable or close to acceptable. Different types of pollution sources and soil physicochemical properties substantially affected the soil residual concentrations of and risks from these pollutants. PTEs in soils collected from agricultural lands around industrial and residential areas and organic pollutants (PAEs and PAHs) in soils collected from agricultural areas around livestock breeding were higher than those from other types of pollution sources and merit long-term monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.
Dong, Yang; Liu, Yi; Chen, Jining
2014-01-01
Urban expansion is a major driving force changing regional hydrology and nonpoint source pollution. The Haihe River Basin, the political, economic, and cultural center of northeastern China, has undergone rapid urbanization in recent decades. To investigate the consequences of future urban sprawl on nonpoint source water pollutant emissions in the river basin, the urban sprawl in 2030 was estimated, and the annual runoff and nonpoint source pollution in the Haihe River basin were simulated. The Integrated Model of Non-Point Sources Pollution Processes (IMPULSE) was used to simulate the effects of urban sprawl on nonpoint source pollution emissions. The outcomes indicated that the urban expansion through 2030 increased the nonpoint source total nitrogen (TN), total phosphorous (TP), and chemical oxygen demand (COD) emissions by 8.08, 0.14, and 149.57 kg/km(2), respectively. Compared to 2008, the total nonpoint emissions rose by 15.33, 0.57, and 12.39 %, respectively. Twelve percent of the 25 cities in the basin would increase by more than 50 % in nonpoint source TN and COD emissions in 2030. In particular, the nonpoint source TN emissions in Xinxiang, Jiaozuo, and Puyang would rise by 73.31, 67.25, and 58.61 %, and the nonpoint source COD emissions in these cities would rise by 74.02, 51.99, and 53.27 %, respectively. The point source pollution emissions in 2008 and 2030 were also estimated to explore the effects of urban sprawl on total water pollution loads. Urban sprawl through 2030 would bring significant structural changes of total TN, TP, and COD emissions for each city in the area. The results of this study could provide insights into the effects of urbanization in the study area and the methods could help to recognize the role that future urban sprawl plays in the total water pollution loads in the water quality management process.
The role of photosynthesis in improving maize tolerance to ozone pollution
USDA-ARS?s Scientific Manuscript database
Ground-level ozone pollution has more than doubled since pre-industrial times, and is currently estimated to cause up to 10% reductions in U.S. maize yields annually. Maize productivity is reduced by exposure to ozone as it diffuses through stomatal pores and reacts to form damaging reactive oxygen ...
Fuzzy rule based estimation of agricultural diffuse pollution concentration in streams.
Singh, Raj Mohan
2008-04-01
Outflow from the agricultural fields carries diffuse pollutants like nutrients, pesticides, herbicides etc. and transports the pollutants into the nearby streams. It is a matter of serious concern for water managers and environmental researchers. The application of chemicals in the agricultural fields, and transport of these chemicals into streams are uncertain that cause complexity in reliable stream quality predictions. The chemical characteristics of applied chemical, percentage of area under the chemical application etc. are some of the main inputs that cause pollution concentration as output in streams. Each of these inputs and outputs may contain measurement errors. Fuzzy rule based model based on fuzzy sets suits to address uncertainties in inputs by incorporating overlapping membership functions for each of inputs even for limited data availability situations. In this study, the property of fuzzy sets to address the uncertainty in input-output relationship is utilized to obtain the estimate of concentrations of a herbicide, atrazine, in a stream. The data of White river basin, a part of the Mississippi river system, is used for developing the fuzzy rule based models. The performance of the developed methodology is found encouraging.
40 CFR 428.95 - Standards of performance for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Mechanical Reclaimed Rubber Subcategory § 428.95 Standards of performance for new sources. (a) The following standards of performance establish the quantity or quality of pollutants or pollutant properties, controlled... or quality of pollutants or pollutant properties, controlled by this section and attributable to pan...
ESTIMATING HEALTH EFFECTS FROM EXPOSURES TO OUTDOOR AND INDOOR SOURCES OF AIR POLLUTION
Individuals are exposed to wide variety of pollutants in various indoor and outdoor microenvironments during the course of a typical day. Sources of pollution in various indoor and outdoor locations produce particulate matter (PM) and gaseous pollutants with different physical an...
40 CFR 421.184 - Standards of performance for new sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Secondary Germanium and Gallium Subcategory § 421.184 Standards of performance for new sources. Any new... liquor. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant... air pollution control. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant...
40 CFR 421.184 - Standards of performance for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Secondary Germanium and Gallium Subcategory § 421.184 Standards of performance for new sources. Any new... liquor. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant... air pollution control. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant...
40 CFR 421.184 - Standards of performance for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Secondary Germanium and Gallium Subcategory § 421.184 Standards of performance for new sources. Any new... liquor. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant... air pollution control. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant...
40 CFR 421.184 - Standards of performance for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Secondary Germanium and Gallium Subcategory § 421.184 Standards of performance for new sources. Any new... liquor. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant... air pollution control. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant...
40 CFR 421.184 - Standards of performance for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Secondary Germanium and Gallium Subcategory § 421.184 Standards of performance for new sources. Any new... liquor. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant or pollutant... air pollution control. NSPS for the Primary and Secondary Germanium and Gallium Subcategory Pollutant...
40 CFR 421.86 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Zinc Subcategory § 421... pollutants in primary zinc process wastewaters introduced into a POTW shall not exceed the following values: (a) Subpart H—Zinc Reduction Furnace Wet Air Pollution Control. PSNS Pollutant or pollutant property...
The Sources of Air Pollution and Their Control.
ERIC Educational Resources Information Center
National Air Pollution Control Administration (DHEW), Arlington, VA.
The problems of air pollution and its control are discussed. Major consideration is given the sources of pollution - motor vehicles, industry, power plants, space heating, and refuse disposal. Annual emission levels of five principle pollutants - carbon monoxide, sulfur dioxide, nitrogen oxides, hydrocarbons, and particulate matter - are listed…
40 CFR 428.76 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... to this subpart that introduces process wastewater pollutants into a publicly owned treatment works... this section. (a) The following pretreatment standard establishes the quantity or quality of pollutants... treatment works by a new point source subject to the provisions of this subpart: Pollutant or pollutant...
40 CFR 428.76 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... to this subpart that introduces process wastewater pollutants into a publicly owned treatment works... this section. (a) The following pretreatment standard establishes the quantity or quality of pollutants... treatment works by a new point source subject to the provisions of this subpart: Pollutant or pollutant...
40 CFR 428.106 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... section. (a) The following pretreatment standard establishes the quantity or quality of pollutants or... works by a new point source subject to the provisions of this subpart: Pollutant or pollutant property...
40 CFR 428.106 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... section. (a) The following pretreatment standard establishes the quantity or quality of pollutants or... works by a new point source subject to the provisions of this subpart: Pollutant or pollutant property...
40 CFR 428.56 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... to this subpart that introduces process wastewater pollutants into a publicly owned treatment works... this section. (a) The following pretreatment standard establishes the quantity or quality of pollutants... treatment works by a new point source subject to the provisions of this subpart: Pollutant or pollutant...
40 CFR 428.56 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... to this subpart that introduces process wastewater pollutants into a publicly owned treatment works... this section. (a) The following pretreatment standard establishes the quantity or quality of pollutants... treatment works by a new point source subject to the provisions of this subpart: Pollutant or pollutant...
Jiang, Mengzhen; Chen, Haiying; Chen, Qinghui
2013-11-01
With the purpose of providing scientific basis for environmental planning about non-point source pollution prevention and control, and improving the pollution regulating efficiency, this paper established the Grid Landscape Contrast Index based on Location-weighted Landscape Contrast Index according to the "source-sink" theory. The spatial distribution of non-point source pollution caused by Jiulongjiang Estuary could be worked out by utilizing high resolution remote sensing images. The results showed that, the area of "source" of nitrogen and phosphorus in Jiulongjiang Estuary was 534.42 km(2) in 2008, and the "sink" was 172.06 km(2). The "source" of non-point source pollution was distributed mainly over Xiamen island, most of Haicang, east of Jiaomei and river bank of Gangwei and Shima; and the "sink" was distributed over southwest of Xiamen island and west of Shima. Generally speaking, the intensity of "source" gets weaker along with the distance from the seas boundary increase, while "sink" gets stronger. Copyright © 2013 Elsevier Ltd. All rights reserved.
Tiruta-Barna, Ligia; Fantozzi-Merle, Catherine; de Brauer, Christine; Barna, Radu
2006-11-16
The aim of this paper is the investigation of the leaching behaviour of different porous materials containing organic pollutants (PAH: naphthalene and phenanthrene). The assessment methodology of long term leaching behaviour of inorganic materials was extended to cement solidified organic pollutants. Based on a scenario-approach considering environmental factors, matrix and pollutants specificities, the applied methodology is composed of adapted equilibrium and dynamic leaching tests. The contributions of different physical and chemical mechanisms were identified and the leaching behaviour was modelled. The physical parameters of the analysed reference and polluted materials are similar. A difference in the pore size distribution appears for higher naphthalene content. The solubility of the PAH contained in the material is affected by the ionic strength and by the presence of a co-solvent; the solution pH does not influence PAH solubility. The solubility of the major mineral species is not influenced by the presence of the two PAH nor by the presence of the methanol as co-solvent in the range of the tested material compositions. In the case of the leaching of a monolith material the main transport mechanism is the diffusion in the porous system. For both mineral and organic species we observed at least two dynamic domains. At the beginning of the leaching process the released flux is due to the surface dissolution and to the diffusion of the main quantity dissolved in the initial pore solution. The second period is governed by a stationary regime between dissolution in pore water and diffusion. The model, coupling transport and chemical phenomena in the pore solution, at the monolith surface and in the leachate simulates satisfactory the release for both mineral and organic species.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-03
...EPA is promulgating national emission standards for hazardous air pollutants for existing stationary compression ignition reciprocating internal combustion engines that either are located at area sources of hazardous air pollutant emissions or that have a site rating of less than or equal to 500 brake horsepower and are located at major sources of hazardous air pollutant emissions. In addition, EPA is promulgating national emission standards for hazardous air pollutants for existing non-emergency stationary compression ignition engines greater than 500 brake horsepower that are located at major sources of hazardous air pollutant emissions. Finally, EPA is revising the provisions related to startup, shutdown, and malfunction for the engines that were regulated previously by these national emission standards for hazardous air pollutants.
Adamo, Paola; Iavazzo, Pietro; Albanese, Stefano; Agrelli, Diana; De Vivo, Benedetto; Lima, Annamaria
2014-12-01
Soil pollution in agricultural lands poses a serious threat to food safety, and suggests the need for consolidated methods providing advisory indications for soil management and crop production. In this work, the three-step extraction procedure developed by the EU Measurement and Testing Programme and two soil-to-plant transfer factors (relative to total and bioavailable concentration of elements in soil) were applied on polluted agricultural soils from southern Italy to obtain information on the retention mechanisms of metals in soils and on their level of translocation to edible vegetables. The study was carried out in the Sarno river plain of Campania, an area affected by severe environmental degradation potentially impacting the health of those consuming locally produced vegetables. Soil samples were collected in 36 locations along the two main rivers flowing into the plain. In 11 sites, lettuce plants were collected at the normal stage of consumption. According to Italian environmental law governing residential soils, and on the basis of soil background reference values for the study area, we found diffuse pollution by Be, Sn and Tl, of geogenic origin, Cr and Cu from anthropogenic sources such as tanneries and intensive agriculture, and more limited pollution by Pb, Zn and V. It was found that metals polluting soils as a result of human activities were mainly associated to residual, oxidizable and reducible phases, relatively immobile and only potentially bioavailable to plants. By contrast, the essential elements Zn and Cu showed a tendency to become more readily mobile and bioavailable as their total content in soil increased and were more easily transported to the edible parts of lettuce than other pollutants. According to our results, current soil pollution in the studied area does not affect the proportion of metals taken up by lettuce plants and there is a limited health risk incurred. Copyright © 2014 Elsevier B.V. All rights reserved.
Effets de la pollution de l’air sur la santé
Abelsohn, Alan; Stieb, Dave M.
2011-01-01
Résumé Objectif Faire connaître aux médecins de famille les effets de la pollution atmosphérique sur la santé et indiquer quels conseils donner aux patients vulnérables pour qu’ils soient moins exposés. Sources de l’information On a consulté MEDLINE à l’aide des termes relatifs à la pollution atmosphérique et à ses effets indésirables. On a révisé les articles en anglais publiés entre janvier 2008 et décembre 2009. La plupart des études contenaient des preuves de niveau II. Principal message Au Canada, la pollution de l’air extérieur cause une morbidité et une mortalité importantes. Elle peut affecter le système respiratoire (exacerbation de l’asthme et de la maladie pulmonaire obstructive chronique) et le système cardiovasculaire (déclencher l’arythmie, l’insuffisance cardiaque et les AVC). La cote air santé (CAS) est un nouvel outil de communication mis au point par Santé Canada et Environnement Canada qui indique sur une échelle de 1 à 10, le risque pour la santé causé par la pollution atmosphérique. La CAS est largement diffusée dans les médias et cet outil pourrait être utile au médecin de famille pour inciter les patients à haut risque (comme ceux qui souffrent d’asthme, de maladie pulmonaire obstructive chronique ou d’insuffisance cardiaque) à réduire leur exposition à la pollution atmosphérique. Conclusion Le médecin de famille peut se servir de la CAS et de ses messages sur la santé pour enseigner aux asthmatiques et aux autres patients à risque élevé la façon de réduire les risques pour la santé causés par la pollution atmosphérique.
40 CFR 458.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 426.64 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 426.44 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 458.36 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 426.106 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new point source subject to the provisions of this subpart. Pollutant...
40 CFR 427.116 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403. In addition, the following pretreatment standard establishes the quantity or quality of pollutants or... works by a new point source subject to the provisions of this subpart. Pollutant or pollutant property...
40 CFR 458.46 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 405.64 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 408.154 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 427.116 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403. In addition, the following pretreatment standard establishes the quantity or quality of pollutants or... works by a new point source subject to the provisions of this subpart. Pollutant or pollutant property...
40 CFR 408.166 - Pretreatment standards for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 408.144 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 458.16 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 408.176 - Pretreatment standards for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or...
40 CFR 426.24 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 426.34 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
40 CFR 427.86 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... quality of pollutants or pollutant properties, controlled by this section, which may be discharged to a publicly owned treatment works by a new point source subject to the provisions of this subpart. Pollutant...
40 CFR 405.64 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... this subpart that introduces process wastewater pollutants into a publicly owned treatment works must... quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart. Pollutant or...
Kaunelienė, Violeta; Meišutovič-Akhtarieva, Marija; Martuzevičius, Dainius
2018-05-08
With the introduction of novel and potentially less polluting nicotine containing products to the market, the impacts of their usage to indoor air quality as opposed to conventional pollution sources must be reviewed and considered. This review study aimed to comparatively analyse changes in indoor air quality as the consequence of tobacco heating system (THS) generated pollution against general indoor air quality in various micro-environments, especially with combustion-based pollution sources present. Indoor concentrations of formaldehyde, acetaldehyde, benzene, toluene, nicotine and PM 2.5 were reviewed and compared; concentrations of other harmful and potentially harmful substances (HPHCs) were discussed. Generally, the usage of THS has been associated with lower or comparable indoor air pollutant concentrations compared against other conventional indoor sources or environments, in most cases distinguishable above background, thus potentially being associated with health effects at prolonged exposures as any other artificial air pollution source. In the controlled environment the use of THS (as well as an electronic cigarette) resulted in the lowest concentrations of formaldehyde, benzene, toluene, PM 2.5, among majority researched pollution sources (conventional cigarettes, waterpipe, incense, mosquito coils). The exposure to significantly higher pollution levels of benzene, toluene, and formaldehyde occurred in public environments, especially transport micro-environments. Such low levels of conventionally-assessed indoor pollutants resulting from the use of new nicotine containing products raise challenges for epidemiological studies of second-hand exposure to THS aerosol in real-life environments. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Andersson, Malin; Klug, Martin; Eggen, Ola Anfin; Ottesen, Rolf Tore
2014-02-01
This study aims to determine the temporal character and concentration variability of polycyclic aromatic hydrocarbon (PAH) during the last 5,400 years in urban lake sediments through a combination of dating and chemo-stratigraphical correlation. We investigate the chemical history of the city of Bergen and determine the effect of specific point sources, as well as diffuse sources, and also help assess the risk of remediation plans. By using several organic compounds, metals and cyanide, we demonstrate the more accurate timing of sedimentation. The PAH results display very low concentrations in pre-industrial times, followed by a general increase that is punctuated by a few significant concentration increases. These most probably correspond to urban fires, domestic heating, gaswork activity and most recently due to traffic pollution. At the same depth as a significant rise in concentration from background levels occurred, the high relative occurrence of low-molecular-weight PAH-compounds, such as naphthalene, were replaced by heavier compounds, thus indicating a permanent change in source. The general observation, using ratios, is that the sources have shifted from pre-industrial pure wood and coal combustion towards mixed and petrogenic sources in more recent times. The (14)C dating provides evidence that the sedimentation rate stayed more-or-less constant for 4,500 years (from 7200 to 2700 calibrated years before present (calyr BP)), before isostatic uplift isolated the water body and the sedimentation rate decreased or sediments were eroded. The sediment input increased again when habitation and industrial activities encroached on the lake. The (14)C dating does not provide consistent data in that period, possibly due to the fact that the lake has been used as a waste site throughout the history of Bergen city. Therefore, results from (14)C dating from anthropogenically influenced sediments should be used with caution. © 2013.
A generalized mathematical scheme is developed to simulate the turbulent dispersion of pollutants which are adsorbed or deposit to the ground. The scheme is an analytical (exact) solution of the atmospheric diffusion equation with height-dependent wind speed a...
40 CFR 419.55 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
... source subject to this subpart which introduces pollutants into a publicly owned treatment works must... following standards apply to the total refinery flow contribution to the POTW: Pollutant or pollutant...
River water quality and pollution sources in the Pearl River Delta, China.
Ouyang, Tingping; Zhu, Zhaoyu; Kuang, Yaoqiu
2005-07-01
Some physicochemical parameters were determined for thirty field water samples collected from different water channels in the Pearl River Delta Economic Zone river system. The analytical results were compared with the environmental quality standards for surface water. Using the SPSS software, statistical analyses were performed to determine the main pollutants of the river water. The main purpose of the present research is to investigate the river water quality and to determine the main pollutants and pollution sources. Furthermore, the research provides some approaches for protecting and improving river water quality. The results indicate that the predominant pollutants are ammonium, phosphorus, and organic compounds. The wastewater discharged from households in urban and rural areas, industrial facilities, and non-point sources from agricultural areas are the main sources of pollution in river water in the Pearl River Delta Economic Zone.
A pollutant removal prediction tool for stormwater derived diffuse pollution.
Revitt, D Michael; Scholes, Lian; Ellis, J Bryan
2008-01-01
This report describes the development of a methodology to theoretically assess the effectiveness of structural BMPs with regard to their treatment of selected stormwater pollutants (metals, polyaromatic hydrocarbons and herbicides). The result is a prioritisation, in terms of pollutant removal efficiency, of 15 different BMPs which can inform stormwater managers and other stakeholders of the best available options for the treatment of urban runoff pollutants of particular environmental concern. Regardless of the selected pollutant, infiltration basins and sub-surface flow constructed wetlands are predicted to perform most efficiently with lagoons, porous asphalt and sedimentation tanks being the least effective systems for the removal of pollutants. The limitations of the approach in terms of the variabilities in BMP designs and applications are considered. (c) IWA Publishing 2008.
ERIC Educational Resources Information Center
Barker, James L.; And Others
This U.S. Environmental Protection Agency report presents estimates of the energy demand attributable to environmental control of pollution from stationary point sources. This class of pollution source includes powerplants, factories, refineries, municipal waste water treatment plants, etc., but excludes mobile sources such as trucks, and…
Analysis of the impact of sources on indoor pollutant concentrations and occupant exposure to indoor pollutants requires knowledge of the emission rates from the sources. Emission rates are often determined by chamber testing and the data from the chamber test are fitted to an em...
75 FR 3392 - Outer Continental Shelf Air Regulations Consistency Update for Alaska
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-21
... 40 CFR part 55,\\1\\ which established requirements to control air pollution from OCS sources in order... air pollution from OCS sources located within 25 miles of States' seaward boundaries that are the same... the Act requires that EPA establish requirements to control air pollution from OCS sources located...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-03
... National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Paints and Allied... when they should not be covered. This action clarifies text of the National Emission Standards for Hazardous Air Pollutants: Paints and Allied Products Manufacturing Area Source Standards which was published...
The role of biofilms as environmental reservoirs of antibiotic resistance
Balcázar, José L.; Subirats, Jéssica; Borrego, Carles M.
2015-01-01
Antibiotic resistance has become a significant and growing threat to public and environmental health. To face this problem both at local and global scales, a better understanding of the sources and mechanisms that contribute to the emergence and spread of antibiotic resistance is required. Recent studies demonstrate that aquatic ecosystems are reservoirs of resistant bacteria and antibiotic resistance genes as well as potential conduits for their transmission to human pathogens. Despite the wealth of information about antibiotic pollution and its effect on the aquatic microbial resistome, the contribution of environmental biofilms to the acquisition and spread of antibiotic resistance has not been fully explored in aquatic systems. Biofilms are structured multicellular communities embedded in a self-produced extracellular matrix that acts as a barrier to antibiotic diffusion. High population densities and proximity of cells in biofilms also increases the chances for genetic exchange among bacterial species converting biofilms in hot spots of antibiotic resistance. This review focuses on the potential effect of antibiotic pollution on biofilm microbial communities, with special emphasis on ecological and evolutionary processes underlying acquired resistance to these compounds. PMID:26583011
Transport of particle-associated elements in two agriculture-dominated boreal river systems.
Marttila, Hannu; Saarinen, Tuomas; Celebi, Ahmet; Kløve, Bjørn
2013-09-01
Transport of particulate pollutants in fluvial systems can contribute greatly to total loads. Understanding transport mechanics under different hydrological conditions is key in successful load estimation. This study analysed trace elements and physico-chemical parameters in time-integrated suspended sediment samples, together with dissolved and total concentrations of pollutants, along two agriculture- and peatland-dominated boreal river systems. The samples were taken in a spatially and temporally comprehensive sampling programme during the ice-free seasons of 2010 and 2011. The hydrochemistry and transport of particle-bound elements in the rivers were strongly linked to intense land use and acid sulphate soils in the catchment area, with arable, pasture and peat areas in particular being main diffuse sources. There were significant seasonal and temporal variations in dissolved and particulate fluxes, but spatial variations were small. Continuous measurements of EC, turbidity and discharge proved to be an accurate indicator of dissolved and particulate fluxes. Overall, the results show that transport of particle-bound elements makes a major contribution to total transport fluxes in agriculture-dominated boreal rivers. Copyright © 2013 Elsevier B.V. All rights reserved.
The role of biofilms as environmental reservoirs of antibiotic resistance.
Balcázar, José L; Subirats, Jéssica; Borrego, Carles M
2015-01-01
Antibiotic resistance has become a significant and growing threat to public and environmental health. To face this problem both at local and global scales, a better understanding of the sources and mechanisms that contribute to the emergence and spread of antibiotic resistance is required. Recent studies demonstrate that aquatic ecosystems are reservoirs of resistant bacteria and antibiotic resistance genes as well as potential conduits for their transmission to human pathogens. Despite the wealth of information about antibiotic pollution and its effect on the aquatic microbial resistome, the contribution of environmental biofilms to the acquisition and spread of antibiotic resistance has not been fully explored in aquatic systems. Biofilms are structured multicellular communities embedded in a self-produced extracellular matrix that acts as a barrier to antibiotic diffusion. High population densities and proximity of cells in biofilms also increases the chances for genetic exchange among bacterial species converting biofilms in hot spots of antibiotic resistance. This review focuses on the potential effect of antibiotic pollution on biofilm microbial communities, with special emphasis on ecological and evolutionary processes underlying acquired resistance to these compounds.
Global distribution of particle phase state in atmospheric secondary organic aerosols
NASA Astrophysics Data System (ADS)
Shiraiwa, Manabu; Li, Ying; Tsimpidi, Alexandra P.; Karydis, Vlassis A.; Berkemeier, Thomas; Pandis, Spyros N.; Lelieveld, Jos; Koop, Thomas; Pöschl, Ulrich
2017-04-01
Secondary organic aerosols (SOA) are a large source of uncertainty in our current understanding of climate change and air pollution. The phase state of SOA is important for quantifying their effects on climate and air quality, but its global distribution is poorly characterized. We developed a method to estimate glass transition temperatures based on the molar mass and molecular O:C ratio of SOA components, and we used the global chemistry climate model EMAC with the organic aerosol module ORACLE to predict the phase state of atmospheric SOA. For the planetary boundary layer, global simulations indicate that SOA are mostly liquid in tropical and polar air with high relative humidity, semi-solid in the mid-latitudes and solid over dry lands. We find that in the middle and upper troposphere SOA should be mostly in a glassy solid phase state. Thus, slow diffusion of water, oxidants and organic molecules could kinetically limit gas-particle interactions of SOA in the free and upper troposphere, promote ice nucleation and facilitate long-range transport of reactive and toxic organic pollutants embedded in SOA.
Global distribution of particle phase state in atmospheric secondary organic aerosols.
Shiraiwa, Manabu; Li, Ying; Tsimpidi, Alexandra P; Karydis, Vlassis A; Berkemeier, Thomas; Pandis, Spyros N; Lelieveld, Jos; Koop, Thomas; Pöschl, Ulrich
2017-04-21
Secondary organic aerosols (SOA) are a large source of uncertainty in our current understanding of climate change and air pollution. The phase state of SOA is important for quantifying their effects on climate and air quality, but its global distribution is poorly characterized. We developed a method to estimate glass transition temperatures based on the molar mass and molecular O:C ratio of SOA components, and we used the global chemistry climate model EMAC with the organic aerosol module ORACLE to predict the phase state of atmospheric SOA. For the planetary boundary layer, global simulations indicate that SOA are mostly liquid in tropical and polar air with high relative humidity, semi-solid in the mid-latitudes and solid over dry lands. We find that in the middle and upper troposphere SOA should be mostly in a glassy solid phase state. Thus, slow diffusion of water, oxidants and organic molecules could kinetically limit gas-particle interactions of SOA in the free and upper troposphere, promote ice nucleation and facilitate long-range transport of reactive and toxic organic pollutants embedded in SOA.
Global distribution of particle phase state in atmospheric secondary organic aerosols
Shiraiwa, Manabu; Li, Ying; Tsimpidi, Alexandra P.; Karydis, Vlassis A.; Berkemeier, Thomas; Pandis, Spyros N.; Lelieveld, Jos; Koop, Thomas; Pöschl, Ulrich
2017-01-01
Secondary organic aerosols (SOA) are a large source of uncertainty in our current understanding of climate change and air pollution. The phase state of SOA is important for quantifying their effects on climate and air quality, but its global distribution is poorly characterized. We developed a method to estimate glass transition temperatures based on the molar mass and molecular O:C ratio of SOA components, and we used the global chemistry climate model EMAC with the organic aerosol module ORACLE to predict the phase state of atmospheric SOA. For the planetary boundary layer, global simulations indicate that SOA are mostly liquid in tropical and polar air with high relative humidity, semi-solid in the mid-latitudes and solid over dry lands. We find that in the middle and upper troposphere SOA should be mostly in a glassy solid phase state. Thus, slow diffusion of water, oxidants and organic molecules could kinetically limit gas–particle interactions of SOA in the free and upper troposphere, promote ice nucleation and facilitate long-range transport of reactive and toxic organic pollutants embedded in SOA. PMID:28429776
Organic micropollutants in wet and dry depositions in the Venice Lagoon.
Gambaro, Andrea; Radaelli, Marta; Piazza, Rossano; Stortini, Angela Maria; Contini, Daniele; Belosi, Franco; Zangrando, Roberta; Cescon, Paolo
2009-08-01
Atmospheric transport is an important route by which pollutants are conveyed from the continents to both coastal and open sea. The role of aerosol deposition in the transport of polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs) and polybromodiphenyls ethers (PBDEs) to water and soil systems has been evaluated by measuring their concentrations in wet and dry depositions to the Venice Lagoon. The organic micropollutant flux data indicate that they contribute to the total deposition flux in different ways through wet and dry deposition, showing that the prevalent contribution derives from wet deposition. The fluxes calculated for PBDEs, showed the prevalence of 47, 99, 100 and 183 congeners, both in dry and wet fluxes. With regard to PCBs, the flux of summation operatorPCB for wet deposition is in the same order of magnitude of the diffusive flux at the air-water interface. The PAH fluxes obtained in the present study are similar to those obtained in previous studies on the atmospheric bulk deposition to the Venice Lagoon. The ratios between Phe/Ant and Fl/Py indicate that the pollutants sources are pyrolytic, deriving from combustion fuels.
Li, Ting-Yuan; Deng, Xue-Jiao; Fan, Shao-Jia; Wu, Dui; Li, Fei; Deng, Tao; Tan, Hao-Bo; Jiang, De-Hai
2012-09-01
Based on the monitoring data of NO2, O3, SO2, PM, visibility, regional air quality index (RAQI) and the atmospheric transport and diffusion data from Nov. 4, 2010 to Dec. 10, 2010 in Guangzhou area, the variations of air quality and meteorological conditions during the Guangzhou Asian Games were analyzed. It was found that, during the Asian Games, the air quality was better than the air quality before or after the Asian Games. The visibility was greater than the visibility before or after the Asian Games, while the concentrations of PM1 and PM2.5 were lower. The correlation coefficient between visibility and the concentrations of PM1, PM2.5 indicated anti-correlation relationships. Daily and hourly concentrations of NO2 and SO2 met the primary ambient air quality standards, whereas the daily concentration of PM10 and hourly concentration of O3 met the secondary ambient air quality standards. Pollutants had been well controlled during the Asian Games. The concentration of SO2 in Guangzhou was influenced by local sources and long distance transmission, while the concentration of NO2 was significantly influenced by local sources. The emissions of NO2, SO2 and PM10 surrounding Guangzhou had a trend to affect the concentrations in Guangzhou, but the situation of O3 was opposite, the relatively high concentration of O3 in Guangzhou had tendency to be transported to the surrounding areas. The pollution meteorology conditions in the period of Asian Games were better than the conditions before or after the Asian Games. The decrease in the concentrations during the Asian Games did not only benefit from the emission control by the government, but also from the good meteorological conditions.
NASA Astrophysics Data System (ADS)
Wepener, V.; van Vuren, J. H. J.; Chatiza, F. P.; Mbizi, Z.; Slabbert, L.; Masola, B.
Effluents are a main source of direct and continuous input of pollutants in aquatic ecosystems. Relating observed effects to specific pollutants or even classes of pollutants remains a very difficult task due to the usually unknown, complex and often highly variable composition of effluents. It is recognized that toxicants interfere with organism integrity at the biochemical level and give rise to effects at the individual level and is manifested in reduced ecologically relevant characteristics such as growth, reproduction and survival, and ultimately at the ecosystem level. By integrating multiple endpoints at different ecologically relevant levels of organization within one test organism, it should be possible to gain understanding in how different levels of organization within this organism respond to toxic exposure and how responses at these different levels are interrelated. This paper presents results from a field study in the Rietvlei Wetland system, Gauteng, South Africa using the freshwater mollusk ( Melanoides tuberculata) and freshwater fish ( Oreochromis mossambicus) as bioindicator organisms. Active biomonitoring (ABM) exposures were conducted where organisms were exposed for 28 days in an effluent dominated river during high flow conditions in April 2003. The river receives effluent from a wastewater treatment plant and an industrial complex, so that up to 75% of the total flow of the river is effluent-based. Effects of field exposure were determined using cellular biomarkers e.g. DNA damage, HSP 70, metallothionein, acetylcholine esterase, lactate dehydrogenase and ethoxyresorufin-o-deethylase activity. The results clearly indicate that although the traditional mortality-based whole effluent toxicity testing did not indicate any toxicity, the in situ exposed organisms were stressed. A multivariate statistical approach was particularly useful for integrating the biomarker responses and highlighting sites at which more detailed analysis of chemical contamination would be useful. Based on the individual biomarker results’ contributing towards the distinct groupings it is possible to conclude that Site 1 is subjected to organic pollutants, whereas Sites 2 and 3 undergo a combination of metallic and organic pollutant stress. However, it is essential that a rapid and sensitive biomarker that is representative of the responses of a suite of biomarkers be tested before ABM can be implemented as a routine biomonitoring practice in water resource management.
Numerical simulation of transverse mixing of waters at the confluence of two rivers
NASA Astrophysics Data System (ADS)
Lyubimova, Tatyana; Lepikhin, Anatoliy; Parshakova, Yanina
2017-04-01
Surface water bodies, both natural (rivers, lakes) and artificial (ponds, reservoirs) are the main source of drinking water. In this regard, special attention should be paid to their pollution, first of all, to extreme pollution, creating a direct danger to their consumption properties. Traditionally, it is believed that the primary mechanism of the pollutants transport in surface water bodies is the Fick diffusion for which the concentration and nature of the pollutants does not affect the transport mechanisms. However, recent studies have shown that these traditional concepts are not always acceptable. In some cases, even relatively low concentrations of pollutants can fundamentally change the hydrodynamics of a flow through a change in density. Density effects playing in these cases an important role can be very important in solving applied problems of water consumption. One an important question is the mechanism of the formation of the streams do not mixing at large distances from the place of confluence of two rivers with significantly different physical and chemical properties of water. In particular, the Vishera river and the Kama river in Perm Region, as evidenced by the numerous space- and aero photographs, virtually do not mix from the place of their confluence to the territory of Solikamsk-Berezniki industrial area. This is fundamentally important for solving the problem of regulation of technological impacts of this source of technogenic pollution, largest in the basin of the Kama river. In the present paper, the phenomenon of a significant weakening of the transverse mixing of water masses in the surface water bodies is investigated with the help of the numerical simulation of the transverse mixing of water masses at the confluence of two rivers. The calculations are carried out with the help of CFD package ANSYS Fluent using k-epsilon model to describe the turbulent pulsations. The dependence of the transverse mixing speed on the flow rates in the confluent rivers typical for the various seasonal periods is studied. It is found that with the growth of the flow rates in confluent rivers the intensity of mixing is reduced. The work was supported by the Russian Foundation for Basic Research and the Government of Perm region (grant 16-41-590005).
Ground Level Ozone Regional Background Characteristics In North-west Pacific Rim
NASA Astrophysics Data System (ADS)
Chiang, C.; Fan, J.; Chang, J. S.
2007-12-01
Understanding the ground level ozone regional background characteristics is essential in understanding the contribution of long-range transport of pollutants from Asia Mainland to air quality in downwind areas. In order to understand this characteristic in north-west Pacific Rim, we conducted a coupled study using ozone observation from regional background stations and 3-D regional-scale chemical transport model simulations. We used O3, CO, wind speed and wind direction data from two regional background stations and ¡§other stations¡¨ over a ten year period and organized several numerical experiments to simulate one spring month in 2003 to obtain a deeper understanding. The so called ¡§other stations¡¨ had actually been named as background stations under various governmental auspices. But we found them to be often under strong influence of local pollution sources with strong diurnal or slightly longer time variations. We found that the Yonagunijima station (24.74 N, 123.02 E) and Heng-Chuen station (21.96 N,120.78 E), about a distance of 400 km apart, have almost the same ozone time series pattern. For these two stations in 2003, correlation coefficients (R2) for annual observed ozone concentration is about 0.64, in the springtime it is about 0.7, and in a one-month period at simulation days it is about 0.76. These two stations have very little small scale variations in all the variables studied. All variations are associated with large scale circulation changes. This is especially so at Yonagunijima station. Using a 3-D regional-scale chemical transport model for East Asia region including contribution from Asia continental outflow and neighboring island pollution areas we found that the Yonagunijima and HengChuen station are indeed free of pollutants from all neighboring areas keeping in mind that pollutants from Taiwan area is never far away. Ozone concentrations in these two stations are dominated by synoptic scale weather patterns, with diffused pollutant contribution from distant sources. When the weather system brings in air mass from the low latitude of western Pacific Ocean, ozone concentrations are about 10-20 ppb. When the China high pressure system moves eastward and with the accompanying Asian continental outflow plume, ozone concentrations are about 65-80 ppb.
NASA Astrophysics Data System (ADS)
Fang, Huaiyang; Lu, Qingshui; Gao, Zhiqiang; Shi, Runhe; Gao, Wei
2013-09-01
China economy has been rapidly increased since 1978. Rapid economic growth led to fast growth of fertilizer and pesticide consumption. A significant portion of fertilizers and pesticides entered the water and caused water quality degradation. At the same time, rapid economic growth also caused more and more point source pollution discharge into the water. Eutrophication has become a major threat to the water bodies. Worsening environment problems forced governments to take measures to control water pollution. We extracted land cover from Landsat TM images; calculated point source pollution with export coefficient method; then SWAT model was run to simulate non-point source pollution. We found that the annual TP loads from industry pollution into rivers are 115.0 t in the entire watershed. Average annual TP loads from each sub-basin ranged from 0 to 189.4 ton. Higher TP loads of each basin from livestock and human living mainly occurs in the areas where they are far from large towns or cities and the TP loads from industry are relatively low. Mean annual TP loads that delivered to the streams was 246.4 tons and the highest TP loads occurred in north part of this area, and the lowest TP loads is mainly distributed in middle part. Therefore, point source pollution has much high proportion in this area and governments should take measures to control point source pollution.
Wilkinson, M E; Quinn, P F; Barber, N J; Jonczyk, J
2014-01-15
Intense farming plays a key role in increasing local scale runoff and erosion rates, resulting in water quality issues and flooding problems. There is potential for agricultural management to become a major part of improved strategies for controlling runoff. Here, a Catchment Systems Engineering (CSE) approach has been explored to solve the above problem. CSE is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. By targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, a significant component of the runoff generation can be managed in turn reducing soil nutrient losses. The Belford catchment (5.7 km(2)) is a catchment scale study for which a CSE approach has been used to tackle a number of environmental issues. A variety of Runoff Attenuation Features (RAFs) have been implemented throughout the catchment to address diffuse pollution and flooding issues. The RAFs include bunds disconnecting flow pathways, diversion structures in ditches to spill and store high flows, large wood debris structure within the channel, and riparian zone management. Here a framework for applying a CSE approach to the catchment is shown in a step by step guide to implementing mitigation measures in the Belford Burn catchment. The framework is based around engagement with catchment stakeholders and uses evidence arising from field science. Using the framework, the flooding issue has been addressed at the catchment scale by altering the runoff regime. Initial findings suggest that RAFs have functioned as designed to reduce/attenuate runoff locally. However, evidence suggested that some RAFs needed modification and new RAFs be created to address diffuse pollution issues during storm events. Initial findings from these modified RAFs are showing improvements in sediment trapping capacities and reductions in phosphorus, nitrate and suspended sediment losses during storm events. © 2013.
Traffic-related air pollution and alveolar nitric oxide in southern California children.
Eckel, Sandrah P; Zhang, Zilu; Habre, Rima; Rappaport, Edward B; Linn, William S; Berhane, Kiros; Zhang, Yue; Bastain, Theresa M; Gilliland, Frank D
2016-05-01
Mechanisms for the adverse respiratory effects of traffic-related air pollution (TRAP) have yet to be established. We evaluated the acute effects of TRAP exposure on proximal and distal airway inflammation by relating indoor nitric oxide (NO), a marker of TRAP exposure in the indoor microenvironment, to airway and alveolar sources of exhaled nitric oxide (FeNO).FeNO was collected online at four flow rates in 1635 schoolchildren (aged 12-15 years) in southern California (USA) breathing NO-free air. Indoor NO was sampled hourly and linearly interpolated to the time of the FeNO test. Estimated parameters quantifying airway wall diffusivity (DawNO) and flux (J'awNO) and alveolar concentration (CANO) sources of FeNO were related to exposure using linear regression to adjust for potential confounders.We found that TRAP exposure indoors was associated with elevated alveolar NO. A 10 ppb higher indoor NO concentration at the time of the FeNO test was associated with 0.10 ppb higher average CANO (95% CI 0.04-0.16) (equivalent to a 7.1% increase from the mean), 4.0% higher J'awNO (95% CI -2.8-11.3) and 0.2% lower DawNO (95% CI -4.8-4.6).These findings are consistent with an airway response to TRAP exposure that was most marked in the distal airways. Copyright ©ERS 2016.
Groundwater Pollution Source Identification using Linked ANN-Optimization Model
NASA Astrophysics Data System (ADS)
Ayaz, Md; Srivastava, Rajesh; Jain, Ashu
2014-05-01
Groundwater is the principal source of drinking water in several parts of the world. Contamination of groundwater has become a serious health and environmental problem today. Human activities including industrial and agricultural activities are generally responsible for this contamination. Identification of groundwater pollution source is a major step in groundwater pollution remediation. Complete knowledge of pollution source in terms of its source characteristics is essential to adopt an effective remediation strategy. Groundwater pollution source is said to be identified completely when the source characteristics - location, strength and release period - are known. Identification of unknown groundwater pollution source is an ill-posed inverse problem. It becomes more difficult for real field conditions, when the lag time between the first reading at observation well and the time at which the source becomes active is not known. We developed a linked ANN-Optimization model for complete identification of an unknown groundwater pollution source. The model comprises two parts- an optimization model and an ANN model. Decision variables of linked ANN-Optimization model contain source location and release period of pollution source. An objective function is formulated using the spatial and temporal data of observed and simulated concentrations, and then minimized to identify the pollution source parameters. In the formulation of the objective function, we require the lag time which is not known. An ANN model with one hidden layer is trained using Levenberg-Marquardt algorithm to find the lag time. Different combinations of source locations and release periods are used as inputs and lag time is obtained as the output. Performance of the proposed model is evaluated for two and three dimensional case with error-free and erroneous data. Erroneous data was generated by adding uniformly distributed random error (error level 0-10%) to the analytically computed concentration values. The main advantage of the proposed model is that it requires only upper half of the breakthrough curve and is capable of predicting source parameters when the lag time is not known. Linking of ANN model with proposed optimization model reduces the dimensionality of the decision variables of the optimization model by one and hence complexity of optimization model is reduced. The results show that our proposed linked ANN-Optimization model is able to predict the source parameters for the error-free data accurately. The proposed model was run several times to obtain the mean, standard deviation and interval estimate of the predicted parameters for observations with random measurement errors. It was observed that mean values as predicted by the model were quite close to the exact values. An increasing trend was observed in the standard deviation of the predicted values with increasing level of measurement error. The model appears to be robust and may be efficiently utilized to solve the inverse pollution source identification problem.
The role of forest in mitigating the impact of atmospheric dust pollution in a mixed landscape.
Santos, Artur; Pinho, Pedro; Munzi, Silvana; Botelho, Maria João; Palma-Oliveira, José Manuel; Branquinho, Cristina
2017-05-01
Atmospheric dust pollution, especially particulate matter below 2.5 μm, causes 3.3 million premature deaths per year worldwide. Although pollution sources are increasingly well known, the role of ecosystems in mitigating their impact is still poorly known. Our objective was to investigate the role of forests located in the surrounding of industrial and urban areas in reducing atmospheric dust pollution. This was tested using lichen transplants as biomonitors in a Mediterranean regional area with high levels of dry deposition. After a multivariate analysis, we have modeled the maximum pollution load expected for each site taking into consideration nearby pollutant sources. The difference between maximum expected pollution load and the observed values was explained by the deposition in nearby forests. Both the dust pollution and the ameliorating effect of forested areas were then mapped. The results showed that forest located nearby pollution sources plays an important role in reducing atmospheric dust pollution, highlighting their importance in the provision of the ecosystem service of air purification.
Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...
Yao, Hong; Li, Weixin; Qian, Xin
2015-01-01
Environmental safety in multi-district boundary regions has been one of the focuses in China and is mentioned many times in the Environmental Protection Act of 2014. Five types were categorized concerning the risk sources for surface water pollution in the multi-provincial boundary region of the Taihu basin: production enterprises, waste disposal sites, chemical storage sites, agricultural non-point sources and waterway transportations. Considering the hazard of risk sources, the purification property of environmental medium and the vulnerability of risk receptors, 52 specific attributes on the risk levels of each type of risk source were screened out. Continuous piecewise linear function model, expert consultation method and fuzzy integral model were used to calculate the integrated risk indexes (RI) to characterize the risk levels of pollution sources. In the studied area, 2716 pollution sources were characterized by RI values. There were 56 high-risk sources screened out as major risk sources, accounting for about 2% of the total. The numbers of sources with high-moderate, moderate, moderate-low and low pollution risk were 376, 1059, 101 and 1124, respectively, accounting for 14%, 38%, 5% and 41% of the total. The procedure proposed could be included in the integrated risk management systems of the multi-district boundary region of the Taihu basin. It could help decision makers to identify major risk sources in the risk prevention and reduction of surface water pollution. PMID:26308032
Yao, Hong; Li, Weixin; Qian, Xin
2015-08-21
Environmental safety in multi-district boundary regions has been one of the focuses in China and is mentioned many times in the Environmental Protection Act of 2014. Five types were categorized concerning the risk sources for surface water pollution in the multi-provincial boundary region of the Taihu basin: production enterprises, waste disposal sites, chemical storage sites, agricultural non-point sources and waterway transportations. Considering the hazard of risk sources, the purification property of environmental medium and the vulnerability of risk receptors, 52 specific attributes on the risk levels of each type of risk source were screened out. Continuous piecewise linear function model, expert consultation method and fuzzy integral model were used to calculate the integrated risk indexes (RI) to characterize the risk levels of pollution sources. In the studied area, 2716 pollution sources were characterized by RI values. There were 56 high-risk sources screened out as major risk sources, accounting for about 2% of the total. The numbers of sources with high-moderate, moderate, moderate-low and low pollution risk were 376, 1059, 101 and 1124, respectively, accounting for 14%, 38%, 5% and 41% of the total. The procedure proposed could be included in the integrated risk management systems of the multi-district boundary region of the Taihu basin. It could help decision makers to identify major risk sources in the risk prevention and reduction of surface water pollution.
Huang, Ning; Wang, Hong Ying; Lin, Tao; Liu, Qi Ming; Huang, Yun Feng; Li, Jian Xiong
2016-10-01
Watershed landscape pattern regulation and optimization based on 'source-sink' theory for non-point source pollution control is a cost-effective measure and still in the exploratory stage. Taking whole watershed as the research object, on the basis of landscape ecology, related theories and existing research results, a regulation framework of watershed landscape pattern for non-point source pollution control was developed at two levels based on 'source-sink' theory in this study: 1) at watershed level: reasonable basic combination and spatial pattern of 'source-sink' landscape was analyzed, and then holistic regulation and optimization method of landscape pattern was constructed; 2) at landscape patch level: key 'source' landscape was taken as the focus of regulation and optimization. Firstly, four identification criteria of key 'source' landscape including landscape pollutant loading per unit area, landscape slope, long and narrow transfer 'source' landscape, pollutant loading per unit length of 'source' landscape along the riverbank were developed. Secondly, nine types of regulation and optimization methods for different key 'source' landscape in rural and urban areas were established, according to three regulation and optimization rules including 'sink' landscape inlay, banding 'sink' landscape supplement, pollutants capacity of original 'sink' landscape enhancement. Finally, the regulation framework was applied for the watershed of Maluan Bay in Xiamen City. Holistic regulation and optimization mode of watershed landscape pattern of Maluan Bay and key 'source' landscape regulation and optimization measures for the three zones were made, based on GIS technology, remote sensing images and DEM model.
Microbial source tracking and transfer hydrodynamics in rural catchments.
NASA Astrophysics Data System (ADS)
Murphy, Sinead; Bhreathnach, Niamh; O'Flaherty, Vincent; Jordan, Philip; Wuertz, Stefan
2013-04-01
In Ireland, bacterial pathogens from continual point source pollution and intermittent pollution from diffuse sources can impact both drinking water supplies and recreational waters. This poses a serious public health threat. Observing and establishing the source of faecal pollution is imperative for the protection of water quality and human health. Traditional culture methods to detect such pollution via faecal indicator bacteria have been widely utilised but do not decipher the source of pollution. To combat this, microbial source tracking, an important emerging molecular tool, is applied to detect host-specific markers in faecally contaminated waters. The aim of this study is to target ruminant and human-specific faecal Bacteroidales and Bacteroides 16S rRNA genes within rural river catchments in Ireland and investigate hydrological transfer dependencies. During storm events and non-storm periods, 1L untreated water samples, taken every 2 hours over a 48-hour time period at the spring (Cregduff) or outlet (Dunleer), and large (5-20L) untreated water samples were collected from two catchment sites. Cregduff is a spring emergence under a grassland karst landscape in Co. Mayo (west coast of Ireland) and Dunleer is a mixed landuse over till soils in Co. Louth (east coast). From a risk assessment point of view, the catchments are very different. Samples were filtered through 0.2µm nitrocellulose filters to concentrate bacterial cells which then underwent chemical extraction of total nucleic acids. Animal and human stool samples were also collected from the catchments to determine assay sensitivity and specificity following nucleic acid extraction. Aquifer response to seasonal events was assessed by monitoring coliforms and E. coli occurrence using the IDEXX Colisure® Quanti Tray®/2000 system in conjunction with chemical and hydrological parameters. Autoanalysers deployed at each catchment monitor multiple water parameters every 10 min such as phosphorus, nitrogen (nitrate), turbidity, conductivity and flow rate. InStat V 3.06 was used to determine correlations between chemical and microbial parameters (P< 0.05 considered significant).There was a positive correlation between E. coli and phosphorus in Cregduff during rain events (p=0.040) & significant correlation for a non-rain periods (<0.001). There was a positive correlation between E. coli and turbidity in Dunleer during rain events (p=0.0008) and in Cregduff during non-rain periods (p=0.0241). The water samples from Dunleer have a higher concentration of phosphorus than in Cregduff. Host specific primers BacCow-UCD, BacHum-UCD, BacUni-UCD and BoBac were then assayed against both faecal and water extracts and quantified using PCR. BacUni-UCD, BacCow-UCD and BoBac detected faecal contamination in three of the four sample sites in Dunleer and BacHum-UCD detected faecal contamination in one of the sites. The concentrations of the BacUni-UCD qPCR assay were higher in the water samples taken from Dunleer outlet than those taken from Cregduff spring. BacCow-UCD and BacHum-UCD qPCR detected low and very low concentrations, respectively, in water from the Dunleer outlet. The concentrations can be seen changing over the hydrograph event. None of the host-specific assays detected pollution in Cregduff. From the results, it can be seen that Dunleer is more subject to contamination than Cregduff.
Tran, Ngoc Han; Gin, Karina Yew-Hoong; Ngo, Huu Hao
2015-12-15
The quality of surface waters/groundwater of a geographical region can be affected by anthropogenic activities, land use patterns and fecal pollution sources from humans and animals. Therefore, the development of an efficient fecal pollution source tracking toolbox for identifying the origin of the fecal pollution sources in surface waters/groundwater is especially helpful for improving management efforts and remediation actions of water resources in a more cost-effective and efficient manner. This review summarizes the updated knowledge on the use of fecal pollution source tracking markers for detecting, evaluating and characterizing fecal pollution sources in receiving surface waters and groundwater. The suitability of using chemical markers (i.e. fecal sterols, fluorescent whitening agents, pharmaceuticals and personal care products, and artificial sweeteners) and/or microbial markers (e.g. F+RNA coliphages, enteric viruses, and host-specific anaerobic bacterial 16S rDNA genetic markers) for tracking fecal pollution sources in receiving water bodies is discussed. In addition, this review also provides a comprehensive approach, which is based on the detection ratios (DR), detection frequencies (DF), and fate of potential microbial and chemical markers. DR and DF are considered as the key criteria for selecting appropriate markers for identifying and evaluating the impacts of fecal contamination in surface waters/groundwater. Copyright © 2015 Elsevier B.V. All rights reserved.
Stable Isotope Mixing Models as a Tool for Tracking Sources of Water and Water Pollutants
One goal of monitoring pollutants is to be able to trace the pollutant to its source. Here we review how mixing models using stable isotope information on water and water pollutants can help accomplish this goal. A number of elements exist in multiple stable (non-radioactive) i...
Building a new regulatory paradigm for coastal and estuarine acidification
NASA Astrophysics Data System (ADS)
Brodeur, J.; Cai, W. J.
2016-02-01
Ocean acidification regulation generally falls under the authority of the Clean Water Act (CWA, P.L. 92-500). The CWA has been a powerful tool to improve the country's water quality, but it is most adept at addressing point-source pollutants and contaminants. It requires policymakers to determine "natural levels" of the target pollutant and to attribute changes in water quality to a specific source, both of which are tough or impossible tests for the diffuse carbon imbalance that is associated with ocean acidification, even if we could easily identify the threshold level for harm to organisms (Boehm, 2015). Even where regulators have tried to apply CWA to address acidification, they have been confronted by a lack of baseline data, an inability to specifically identify sources within their jurisdiction, and the fact that existing water quality standards do not capture the impairments that are associated with ocean acidification (Cooley, 2015). In fact, there was a lawsuit brought by the Center for Biological Diversity against the U.S. Environmental Protection Agency (EPA) alleging the agency had failure to regulate this issue. In the end, the courts sided with the EPA, and it continues to struggle with how to use pH and/or saturation state to define a point at which a water body becomes impaired and a threat to sea-life and natural resources. We present an analysis of the complexities related to regulating ocean acidification, the history of work in this area, and suggest a solution that can be tailored to fit unique coastal and estuarine characteristics.
Building a new regulatory paradigm for coastal and estuarine acidification
NASA Astrophysics Data System (ADS)
Brodeur, J.; Cai, W. J.
2016-12-01
Ocean acidification regulation generally falls under the authority of the Clean Water Act (CWA, P.L. 92-500). The CWA has been a powerful tool to improve the country's water quality, but it is most adept at addressing point-source pollutants and contaminants. It requires policymakers to determine "natural levels" of the target pollutant and to attribute changes in water quality to a specific source, both of which are tough or impossible tests for the diffuse carbon imbalance that is associated with ocean acidification, even if we could easily identify the threshold level for harm to organisms (Boehm, 2015). Even where regulators have tried to apply CWA to address acidification, they have been confronted by a lack of baseline data, an inability to specifically identify sources within their jurisdiction, and the fact that existing water quality standards do not capture the impairments that are associated with ocean acidification (Cooley, 2015). In fact, there was a lawsuit brought by the Center for Biological Diversity against the U.S. Environmental Protection Agency (EPA) alleging the agency had failure to regulate this issue. In the end, the courts sided with the EPA, and it continues to struggle with how to use pH and/or saturation state to define a point at which a water body becomes impaired and a threat to sea-life and natural resources. We present an analysis of the complexities related to regulating ocean acidification, the history of work in this area, and suggest a solution that can be tailored to fit unique coastal and estuarine characteristics.
Natural and anthropogenic factors affecting the groundwater quality in Serbia.
Devic, Gordana; Djordjevic, Dragana; Sakan, Sanja
2014-01-15
Various chemometric techniques were used to analyze the quality of groundwater data sets. Seventeen water quality parameters: the cations Na, K, Ca, Mg, the anions Cl, SO4, NO3, HCO3 and nine trace elements Pb, As, Mn, Ni, Cu, Cd, Fe, Zn and Cr were measured at 66 different key sampling sites in ten representative areas (low land-Northern Autonomous Province of Serbia, Vojvodina and central Serbia) for the summer period of 2009. HCA grouped the sample sites into four clusters based on the similarities of the characteristics of the groundwater quality. DA showed two parameters, HCO3 and Zn, affording more than 90% correct assignments in the spatial analysis of four/three different regions in Serbia. Factor analysis was applied on the log-transformed data sets and allowed the identification of a reduced number of factors with hydrochemical meaning. The results showed severe pollution with Mn, As, NO3, Ni, Pb whereby anthropogenic origin of these contaminants was indicated. The pollution comes from both scattered point sources (industrial and urban effluent) and diffuse source agricultural activity. These samples may not be suitable for human consumption; the water quality belongs to class III/IV (contaminated). The Fe anomalies (7.1mg/L) in the water from the Vetrnica site can be attributed to natural sources, such as the dissolution of rock masses and rock fragments. The serious groundwater contamination with As (25.7-137.8 μg/L) in the area of Banat (Northern Autonomous Province of Serbia, Vojvodina) and a sample No. 9 at the Great Morava River requires urgent attention. © 2013.
Pollution source localization in an urban water supply network based on dynamic water demand.
Yan, Xuesong; Zhu, Zhixin; Li, Tian
2017-10-27
Urban water supply networks are susceptible to intentional, accidental chemical, and biological pollution, which pose a threat to the health of consumers. In recent years, drinking-water pollution incidents have occurred frequently, seriously endangering social stability and security. The real-time monitoring for water quality can be effectively implemented by placing sensors in the water supply network. However, locating the source of pollution through the data detection obtained by water quality sensors is a challenging problem. The difficulty lies in the limited number of sensors, large number of water supply network nodes, and dynamic user demand for water, which leads the pollution source localization problem to an uncertainty, large-scale, and dynamic optimization problem. In this paper, we mainly study the dynamics of the pollution source localization problem. Previous studies of pollution source localization assume that hydraulic inputs (e.g., water demand of consumers) are known. However, because of the inherent variability of urban water demand, the problem is essentially a fluctuating dynamic problem of consumer's water demand. In this paper, the water demand is considered to be stochastic in nature and can be described using Gaussian model or autoregressive model. On this basis, an optimization algorithm is proposed based on these two dynamic water demand change models to locate the pollution source. The objective of the proposed algorithm is to find the locations and concentrations of pollution sources that meet the minimum between the analogue and detection values of the sensor. Simulation experiments were conducted using two different sizes of urban water supply network data, and the experimental results were compared with those of the standard genetic algorithm.
Gonzalez, Mariana; Miglioranza, Karina S B; Grondona, Sebastían I; Silva Barni, Maria Florencia; Martinez, Daniel E; Peña, Aránzazu
2013-04-01
This study is aimed at analyzing the occurrence and transport of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the Quequén Grande river basin, as representative of a catchment under diffuse pollution sources. Pollutant levels in soils, river bottom sediments (RBS), streamwater (Sw), suspended particle materials (SPMs), macrophytes and muscle of silverside were determined by GC-ECD. Soil K(d) values for the current-used insecticides, endosulfans and cypermethrin, were established. Total levels (ng g(-1) dry weight) in soil ranged between 0.07–0.9 for OCPs, 0.03–0.37 for PCBs and 0.01–0.05 for PBDEs. Endosulfan insecticide (α- + b- + sulfate metabolite) represented up to 72.5% of OCPs. The low soil retention for α-endosulfan (K(d): 77) and endosulfan sulfate (K(d): 100) allows their transport to Sw, SPM and RBS. Levels of endosulfan in Sw in some cases exceeded the value postulated by international guidelines for aquatic biota protection (3 ng L(-1)). PCB and PBDE pollution was related to harbour, dumping sites and pile tire burning. Tri and hexa PCB congeners predominated in all matrices and exceeded the quality guideline value of 0.04 ng L(-1) in Sw. Considering levels in silverside muscle, none of the oral reference doses were exceeded, however, PCBs accounted for 18.6% of the total daily allowed ingest for a 70 kg individual. Although the levels of PCBs and OCPs in soil and RBS were low and did not go beyond quality guidelines, these compounds could still represent a risk to aquatic biota and humanbeings, and thus actions towards preventing this situation should be undertaken.
Passive samplers were used to determine water concentrations of persistent organic pollutants (POPs) in the surface sediments and near-bottom water of a marine Superfund site on the Palos Verdes Shelf, California, USA. Measured concentrations in the porewater and water column at...
Photogrammetric and photometric investigation of a smoke plume viewed from space.
NASA Technical Reports Server (NTRS)
Randerson, D.; Garcia, J. G.; Whitehead, V. S.
1971-01-01
Use of detailed analyses of an Apollo 6 stereographic photograph of a smoke plume which originated in southern Arizona and crossed over into Mexico to illustrate how high-resolution photography can aid meteorologists in evaluating specific air pollution events. Photogrammetric analysis of the visible smoke plume revealed that the plume was 8.06 miles long and attained a maximum width of 4000 ft, 3.0 miles from the 570-ft chimney emitting the effluent. Stereometric analysis showed that the visible top of the plume rose nearly 2400 ft above stack top, attaining 90% of this total rise 1.75 miles downwind from the source. Photometric analysis of the plume revealed a field of plume optical density that portrayed leptokurtic and bimodal distributions rather than a true Gaussian distribution. A horizontal eddy diffusivity of about 650,000 sq cm/sec and a vertical eddy diffusivity of 230,000 sq cm/sec were determined from the plume dimensions. Neutron activation analysis of plume samples revealed the elemental composition of the smoke to be copper, arsenic, selenium, indium and antimony, with trace amounts of vanadium and scandium.
FECAL POLLUTION, PUBLIC HEALTH AND MICROBIAL SOURCE TRACKING
Microbial source tracking (MST) seeks to provide information about sources of fecal water contamination. Without knowledge of sources, it is difficult to accurately model risk assessments, choose effective remediation strategies, or bring chronically polluted waters into complian...
Nonpoint source pollution of urban stormwater runoff: a methodology for source analysis.
Petrucci, Guido; Gromaire, Marie-Christine; Shorshani, Masoud Fallah; Chebbo, Ghassan
2014-09-01
The characterization and control of runoff pollution from nonpoint sources in urban areas are a major issue for the protection of aquatic environments. We propose a methodology to quantify the sources of pollutants in an urban catchment and to analyze the associated uncertainties. After describing the methodology, we illustrate it through an application to the sources of Cu, Pb, Zn, and polycyclic aromatic hydrocarbons (PAH) from a residential catchment (228 ha) in the Paris region. In this application, we suggest several procedures that can be applied for the analysis of other pollutants in different catchments, including an estimation of the total extent of roof accessories (gutters and downspouts, watertight joints and valleys) in a catchment. These accessories result as the major source of Pb and as an important source of Zn in the example catchment, while activity-related sources (traffic, heating) are dominant for Cu (brake pad wear) and PAH (tire wear, atmospheric deposition).
40 CFR 415.426 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2012 CFR
2012-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Hydrogen Cyanide... Sources (PSNS): Subpart AP—Hydrogen Cyanide Pollutant or pollutant property PSNS effluent limitations...
40 CFR 415.426 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Hydrogen Cyanide... Sources (PSNS): Subpart AP—Hydrogen Cyanide Pollutant or pollutant property PSNS effluent limitations...
40 CFR 415.426 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2014 CFR
2014-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Hydrogen Cyanide... Sources (PSNS): Subpart AP—Hydrogen Cyanide Pollutant or pollutant property PSNS effluent limitations...
40 CFR 415.426 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Hydrogen Cyanide... Sources (PSNS): Subpart AP—Hydrogen Cyanide Pollutant or pollutant property PSNS effluent limitations...
1987-11-01
Congress theme was "Hydraulic Research for Water Management in the Eighties." Actual subjects selected for discussion were: a. Subsurface Flow, Pollutant ...problems experienced by this country. Water availability and water management are troublesome, particu- larly in the interior. Pollution and the environment...34Applied Study On Pollutant and Heat Diffusion Around Underground Cavern." Technical Session 6B - 1600-1730 Tuesday 20th August 1985 Sub-theme B.(c
Risk Assessment for Toxic Air Pollutants: A Citizen's Guide
... from the source(s). Engineers use either monitors or computer models to estimate the amount of pollutant released ... measure how much of the pollutant is present. Computer models use mathematical equations that represent the processes ...
AIR POLLUTION CONTROL TECHNOLOGIES (CHAPTER 65)
The chapter discusses the use of technologies for reducing air pollution emissions from stationary sources, with emphasis on the control of combustion gen-erated air pollution. Major stationary sources include utility power boilers, industrial boilers and heaters, metal smelting ...
Suo, An-ning; Wang, Tian-ming; Wang, Hui; Yu, Bo; Ge, Jian-ping
2006-12-01
Non-point sources pollution is one of main pollution modes which pollutes the earth surface environment. Aimed at soil water loss (a typical non-point sources pollution problem) on the Losses Plateau in China, the paper applied a landscape patternevaluation method to twelve watersheds of Jinghe River Basin on the Loess Plateau by means of location-weighted landscape contrast index(LCI) and landscape slope index(LSI). The result showed that LSI of farm land, low density grass land, forest land and LCI responded significantly to soil erosion modulus and responded to depth of runoff, while the relationship between these landscape index and runoff variation index and erosion variation index were not statistically significant. This tell us LSI and LWLCI are good indicators of soil water loss and thus have big potential in non-point source pollution risk evaluation.
Localized Enzymatic Degradation of Polymers: Physics and Scaling Laws
NASA Astrophysics Data System (ADS)
Lalitha Sridhar, Shankar; Vernerey, Franck
2018-03-01
Biodegradable polymers are naturally abundant in living matter and have led to great advances in controlling environmental pollution due to synthetic polymer products, harnessing renewable energy from biofuels, and in the field of biomedicine. One of the most prevalent mechanisms of biodegradation involves enzyme-catalyzed depolymerization by biological agents. Despite numerous studies dedicated to understanding polymer biodegradation in different environments, a simple model that predicts the macroscopic behavior (mass and structural loss) in terms of microphysical processes (enzyme transport and reaction) is lacking. An interesting phenomenon occurs when an enzyme source (released by a biological agent) attacks a tight polymer mesh that restricts free diffusion. A fuzzy interface separating the intact and fully degraded polymer propagates away from the source and into the polymer as the enzymes diffuse and react in time. Understanding the characteristics of this interface will provide crucial insight into the biodegradation process and potential ways to precisely control it. In this work, we present a centrosymmetric model of biodegradation by characterizing the moving fuzzy interface in terms of its speed and width. The model predicts that the characteristics of this interface are governed by two time scales, namely the polymer degradation and enzyme transport times, which in turn depend on four main polymer and enzyme properties. A key finding of this work is simple scaling laws that can be used to guide biodegradation of polymers in different applications.
Assessing groundwater vulnerability to agrichemical contamination in the Midwest US
Burkart, M.R.; Kolpin, D.W.; James, D.E.
1999-01-01
Agrichemicals (herbicides and nitrate) are significant sources of diffuse pollution to groundwater. Indirect methods are needed to assess the potential for groundwater contamination by diffuse sources because groundwater monitoring is too costly to adequately define the geographic extent of contamination at a regional or national scale. This paper presents examples of the application of statistical, overlay and index, and process-based modeling methods for groundwater vulnerability assessments to a variety of data from the Midwest U.S. The principles for vulnerability assessment include both intrinsic (pedologic, climatologic, and hydrogeologic factors) and specific (contaminant and other anthropogenic factors) vulnerability of a location. Statistical methods use the frequency of contaminant occurrence, contaminant concentration, or contamination probability as a response variable. Statistical assessments are useful for defining the relations among explanatory and response variables whether they define intrinsic or specific vulnerability. Multivariate statistical analyses are useful for ranking variables critical to estimating water quality responses of interest. Overlay and index methods involve intersecting maps of intrinsic and specific vulnerability properties and indexing the variables by applying appropriate weights. Deterministic models use process-based equations to simulate contaminant transport and are distinguished from the other methods in their potential to predict contaminant transport in both space and time. An example of a one-dimensional leaching model linked to a geographic information system (GIS) to define a regional metamodel for contamination in the Midwest is included.
Numerical analysis of diffusion around a suspended expressway by a multi-scale CFD model
NASA Astrophysics Data System (ADS)
kondo, Hiroaki; Asahi, Kazutake; Tomizuka, Takayuki; Suzuki, Motoo
The diffusion of NO x around Ikegami-Shinmachi crossroads, which are among the most polluted roadside areas in Japan, was analyzed with a CFD model. This is a suspended four-lane express road with a six-lane ground-level road under the expressway and another four-lane ground-level road intersecting the two roads. Three types of boundary conditions for the CFD model were tested. In the first case, the boundary conditions were given with the results from the mesoscale meteorological model; in other words, the model was multi-scale. In the second case, the boundary conditions were given with the local one-point observation. In the third case, the conditions for the wind were given with the observation, and those for the turbulence were given with the mesoscale numerical model. All of the calculations indicated high concentrations in the morning and low ones in the afternoon, but they did not indicate high concentrations in the evening. The reasons for such time variations of NO x concentrations were investigated from the viewpoints of the wind direction, velocity, and boundary layer height. The results suggested that the extremely high concentration was generated by local sources and advection from the large source area of Tokyo. On the whole, the calculation with the boundary condition with the mesoscale model appears to be better than the other calculations.
Skyglow effects in UV and visible spectra: Radiative fluxes
NASA Astrophysics Data System (ADS)
Kocifaj, Miroslav; Solano Lamphar, Hector Antonio
2013-09-01
Several studies have tried to understand the mechanisms and effects of radiative transfer under different night-sky conditions. However, most of these studies are limited to the various effects of visible spectra. Nevertheless, the invisible parts of the electromagnetic spectrum can pose a more profound threat to nature. One visible threat is from what is popularly termed skyglow. Such skyglow is caused by injudiciously situated or designed artificial night lighting systems which degrade desired sky viewing. Therefore, since lamp emissions are not limited to visible electromagnetic spectra, it is necessary to consider the complete spectrum of such lamps in order to understand the physical behaviour of diffuse radiation at terrain level. In this paper, the downward diffuse radiative flux is computed in a two-stream approximation and obtained ultraviolet spectral radiative fluxes are inter-related with luminous fluxes. Such a method then permits an estimate of ultraviolet radiation if the traditionally measured illuminance on a horizontal plane is available. The utility of such a comparison of two spectral bands is shown, using the different lamp types employed in street lighting. The data demonstrate that it is insufficient to specify lamp type and its visible flux production independently of each other. Also the UV emissions have to be treated by modellers and environmental scientists because some light sources can be fairly important pollutants in the near ultraviolet. Such light sources can affect both the living organisms and ambient environment.
State of the art molecular markers for fecal pollution source tracking in water.
Roslev, Peter; Bukh, Annette S
2011-03-01
Most environmental waters are susceptible to fecal contamination from animal and/or human pollution sources. To attenuate or eliminate such contamination, it is often critical that the pollution sources are rapidly and correctly identified. Fecal pollution source tracking (FST) is a promising research area that aims to identify the origin(s) of fecal pollution in water. This mini-review focuses on the potentials and limitations of library independent molecular markers that are exclusively or strongly associated with fecal pollution from humans and different animals. Fecal-source-associated molecular markers include nucleic acid sequences from prokaryotes and viruses associated with specific biological hosts, but also sequences such as mitochondrial DNA retrieved directly from humans and animals. However, some fecal-source-associated markers may not be absolutely specific for a given source type, and apparent specificity and frequency established in early studies are sometimes compromised by new studies suggesting variation in specificity and abundance on a regional, global and/or temporal scale. It is therefore recommended that FST studies are based on carefully selected arrays of markers, and that identification of human and animal contributions are based on a multi-marker toolkit with several markers for each source category. Furthermore, future FST studies should benefit from increased knowledge regarding sampling strategies and temporal and spatial variability of marker ratios. It will also be important to obtain a better understanding of marker persistence and the quantitative relationship between marker abundance and the relative contribution from individual fecal pollution source types. A combination of enhanced pathogen screening methods, and validated quantitative source tracking techniques could then contribute significantly to future management of environmental water quality including improved microbial risk assessment.
40 CFR 415.24 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2012 CFR
2012-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Aluminum Sulfate... standards for existing sources (PSES): Subpart B—Aluminum Sulfate Pollutant or pollutant property PSES...
40 CFR 415.24 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2014 CFR
2014-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Aluminum Sulfate... standards for existing sources (PSES): Subpart B—Aluminum Sulfate Pollutant or pollutant property PSES...
40 CFR 415.24 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Aluminum Sulfate... standards for existing sources (PSES): Subpart B—Aluminum Sulfate Pollutant or pollutant property PSES...
40 CFR 415.14 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Aluminum Chloride... standards for existing sources (PSES): Subpart A—Aluminum Chloride Pollutant or pollutant property PSES...
Identifiability and identification of trace continuous pollutant source.
Qu, Hongquan; Liu, Shouwen; Pang, Liping; Hu, Tao
2014-01-01
Accidental pollution events often threaten people's health and lives, and a pollutant source is very necessary so that prompt remedial actions can be taken. In this paper, a trace continuous pollutant source identification method is developed to identify a sudden continuous emission pollutant source in an enclosed space. The location probability model is set up firstly, and then the identification method is realized by searching a global optimal objective value of the location probability. In order to discuss the identifiability performance of the presented method, a conception of a synergy degree of velocity fields is presented in order to quantitatively analyze the impact of velocity field on the identification performance. Based on this conception, some simulation cases were conducted. The application conditions of this method are obtained according to the simulation studies. In order to verify the presented method, we designed an experiment and identified an unknown source appearing in the experimental space. The result showed that the method can identify a sudden trace continuous source when the studied situation satisfies the application conditions.
This research program was initiated with the overall objective of gaining understanding of the flow and diffusion of pollutants in complex terrain under both neutral and stably stratified conditions. This report covers the first phase of the project; it describes the flow structu...
NASA Astrophysics Data System (ADS)
Qian, J.; He, Q.
2014-12-01
This paper developed a high resolution emission inventory of major pollutants in city cluster of Sichuan Basin, one of the most polluted regions in China. The city cluster included five cities, which were Chengdu, Deyang, Mianyang, Meishan and Ziyang. Pollution source census and field measurements were conducted for the major emission sources such as the industry sources, on-road mobile sources, catering sources and the dust sources. The inventory results showed that in the year of 2012, the emission of SO2、NOX、CO、PM10、PM2.5、VOCs and NH3 in the region were 143.5、251.9、1659.9、299.3、163.5、464.1 and 995kt respectively. Chengdu, the provincial capital city, had the largest emission load of every pollutant among the cities. The industry sources, including power plants, fuel combustion facilities and non-combustion processes were the largest emission sources for SO2、NOX and CO, contributing to 84%, 46.5%, 35% of total SO2, NOX and CO emissions. On-road mobile sources accounted for 46.5%, 33%, 16% of the total NOx, CO, PM2.5 emissions and 28% of the anthropogenic VOCs emission. Dust and industry sources contributed to 42% and 23% of the PM10 emission with the dust sources also as the largest source of PM2.5, contributing to 27%. Anthropogenic and biogenic sources took 75% and 25% of the total VOCs emission while 36% of anthropogenic VOCs emission was owing to solvent use. Livestock contributed to 62% of NH3 emissions, followed by nitrogen fertilizer application whose contribution was 23%. Based on the developed emission inventory and local meteorological data, the regional air quality modeling system WRF-CMAQ was applied to simulate the status of PM2.5 pollution in a regional scale. The results showed that high PM2.5 concentration was distributed over the urban area of Chengdu and Deyang. On-road mobile sources and dust sources were two major contributors to the PM2.5 pollution in Chengdu, both had an contribution ratio of 27%. In Deyang, Mianyang, Meishan and Ziyang, industry sources had a relatively high contribution ratio to the PM2.5 pollution, accounting for about 35%, 33%, 38% and 24% respectively.
FIRST ORDER ESTIMATES OF ENERGY REQUIREMENTS FOR POLLUTION CONTROL
This report presents estimates of the energy demand attributable to environmental control of pollution from 'stationary point sources.' This class of pollution source includes powerplants, factories, refineries, municipal waste water treatment plants, etc., but excludes 'mobile s...
Modeling Nitrogen Fate and Transport at the Sediment-Water ...
Diffusive mass transfer at media interfaces exerts control on the fate and transport of pollutants originating from agricultural and urban landscapes and affects the con-ditions of water bodies. Diffusion is essentially a physical process affecting the distribution and fate of various environmental pollutants such as nutrients, pesticides, metals, PCBs, PAHs, etc. Environmental problems caused by excessive use of agricultural chemicals (e.g., pesticides and fertilizers) and improper discharge of industrial waste and fuel leaks are all influenced by the diffusive nature of pollutants in the environment. Eutrophication is one such environmental problem where the sediment-water interface exerts a significant physical and geochemical control on the eutrophic condition of the stressed water body. Exposure of streams and lakes to contaminated sediment is another common environmental problem whereby transport of the contaminant (PCBs, PAHs, and other organic contaminants) across the sediment water can increase the risk for exposure to the chemicals and pose a significant health hazard to aquatic life and human beings. This chapter presents analytical and numerical models describing fate and transport phenomena at the sediment-water interface in freshwater ecosystems, with the primary focus on nitrogen cycling and the applicability of the models to real-world environmental problems and challenges faced in their applications. The first model deals with nitrogen cycling
Testing Method of Degrading Heavy Oil Pollution by Microorganisms
NASA Astrophysics Data System (ADS)
Wu, Qi; Zhao, Lin; Ma, Aijin
2018-01-01
With the development of human society, we are more and more relying on the petrochemical energy. The use of petrochemical energy not only brings us great convenience, but is also accompanied by a series of environmental pollution problems, especially oil pollution. Since it is impractical to restore all pollution problems, the proper use of some remedial measures, under the guidance of functional orientation, may be sufficient to minimize the risk of persistent and diffusing pollutants. In recent years, bioremediation technology has been gradually developed into a promising stage and has played a crucial role in the degradation of heavy oil pollution. Specially, microbes in the degradation of heavy oil have made a great contribution. This paper mainly summarizes the different kinds of microorganisms for degrading heavy oil and the detection method for degradation efficiency of heavy oil pollution.
NASA Astrophysics Data System (ADS)
Buchty-Lemke, Michael; Frings, Roy; Hagemann, Lukas; Lehmkuhl, Frank; Maaß, Anna-Lisa; Schwarzbauer, Jan
2016-04-01
The Wurm River (Lower Rhine Embayment, Germany) is a small stream in a low mountain area near the Dutch-German border that has seen a lot of anthropogenic changes of its morphology since medieval times. Among other influencing factors, water mills, in particular, had an early impact on the sediment dynamics and created sediment traps. Several knickpoints in the long profile may represent the legacy of mill damming - or founded mill building at these spots. The knickpoints may also represent the aftermath of the colliery history. A study site in the upper reaches of the Wurm River features erosion terraces, incised following the demise of a mill dam in the early 20th century. The mill pond most likely collected sediment and additives e.g. used in agricultural and industrial processes. These legacy sediments from behind former mill dams provide information about anthropogenic pollution, particularly for the era of industrialization in the vicinity of the old industrial area of the city of Aachen. Along with the demise of the mill dam and the increased incision tendency, the sediments are also a secondary source for pollution in case of remobilization of contaminated sediments. Two major research questions are addressed. A) Which individual hydrological and geomorphological processes, both upstream and downstream, triggered the incision and the construction of the erosion terraces, which are preserved in the mill pond sediments? Is either the demised mill dam, or subsidence effects, or a combination of both the determining factor? B) Which contaminants are retained in the sediments? Is there a detectable point source for the pollutants or is it a mixture of diffuse anthropogenic (industry, agriculture, traffic, wastewater) and natural origin? To tackle these questions, sedimentological data are combined with geomorphological mapping and evaluation of historical data. A soil profile provides insight into the architecture of the floodplain, which is built of riverbed sediments overlain by stratified fine clastic and organic-rich material, representing the sediment being trapped when the mill dam existed. X-ray fluorescence and grain size analysis are used to determine the depositional process, provenance and chemostratigraphy. Knowledge about the distribution and fate of pollutants in sediments is valuable for river management purposes. Measures within the scope of the EU Water Framework Directive have been implemented at several breaches at the Wurm River, and further ones are planned. Potential risks due to remobilization of polluted alluvial sediments must thereby be taken into account. Furthermore, e.g. dismantling of transverse structures to improve passage for fish might trigger similar erosion processes and affects the sediment continuity.
The model SIRANE for atmospheric urban pollutant dispersion; part I, presentation of the model
NASA Astrophysics Data System (ADS)
Soulhac, Lionel; Salizzoni, Pietro; Cierco, F.-X.; Perkins, Richard
2011-12-01
In order to control and manage urban air quality, public authorities require an integrated approach that incorporates direct measurements and modelling of mean pollutant concentrations. These have to be performed by means of operational modelling tools, that simulate the transport of pollutants within and above the urban canopy over a large number of streets. The operational models must be able to assess rapidly a large variety of situations and with limited computing resources. SIRANE is an operational urban dispersion model based on a simplified description of the urban geometry that adopts parametric relations for the pollutant transfer phenomena within and out of the urban canopy. The streets in a city district are modelled as a network of connected street segments. The flow within each street is driven by the component of the external wind parallel to the street, and the pollutant is assumed to be uniformly mixed within the street. The model contains three main mechanisms for transport in and out of a street: advection along the street axis, diffusion across the interface between the street and the overlying air flow and exchanges with other streets at street intersections. The dispersion of pollutants advected or diffused out of the streets is taken into account using a Gaussian plume model, with the standard deviations σ y and σ z parameterised by the similarity theory. The input data for the final model are the urban geometry, the meteorological parameters, the background concentration of pollutants advected into the model domain by the wind and the emissions within each street in the network.
NASA Astrophysics Data System (ADS)
Li, L.; An, J. Y.; Zhou, M.; Yan, R. S.; Huang, C.; Lu, Q.; Lin, L.; Wang, Y. J.; Tao, S. K.; Qiao, L. P.; Zhu, S. H.; Chen, C. H.
2015-12-01
An extremely high PM2.5 pollution episode occurred over the eastern China in January 2013. In this paper, the particulate matter source apportionment technology (PSAT) method coupled within the Comprehensive air quality model with extensions (CAMx) is applied to study the source contributions to PM2.5 and its major components at six receptors (Urban Shanghai, Chongming, Dianshan Lake, Urban Suzhou, Hangzhou and Zhoushan) in the Yangtze River Delta (YRD) region. Contributions from 4 source areas (including Shanghai, South Jiangsu, North Zhejiang and Super-region) and 9 emission sectors (including power plants, industrial boilers and kilns, industrial processing, mobile source, residential, volatile emissions, dust, agriculture and biogenic emissions) to PM2.5 and its major components (sulfate, nitrate, ammonia, organic carbon and elemental carbon) at the six receptors in the YRD region are quantified. Results show that accumulation of local pollution was the largest contributor during this air pollution episode in urban Shanghai (55%) and Suzhou (46%), followed by long-range transport (37% contribution to Shanghai and 44% to Suzhou). Super-regional emissions play an important role in PM2.5 formation at Hangzhou (48%) and Zhoushan site (68%). Among the emission sectors contributing to the high pollution episode, the major source categories include industrial processing (with contributions ranging between 12.7 and 38.7% at different receptors), combustion source (21.7-37.3%), mobile source (7.5-17.7%) and fugitive dust (8.4-27.3%). Agricultural contribution is also very significant at Zhoushan site (24.5%). In terms of the PM2.5 major components, it is found that industrial boilers and kilns are the major source contributor to sulfate and nitrate. Volatile emission source and agriculture are the major contributors to ammonia; transport is the largest contributor to elemental carbon. Industrial processing, volatile emissions and mobile source are the most significant contributors to organic carbon. Results show that the Yangtze River Delta region should focus on the joint pollution control of industrial processing, combustion emissions, mobile source emissions, and fugitive dust. Regional transport of air pollution among the cities are prominent, and the implementation of regional joint prevention and control of air pollution will help to alleviate fine particulate matter concentrations under heavy pollution case significantly.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 29 2010-07-01 2010-07-01 false BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That use End-of-Pipe Biological Treatment 4 Table 4... Limitations for Priority Pollutants for Direct Discharge Point Sources That use End-of-Pipe Biological...
Final Environmental Impact Statement for Langley
NASA Technical Reports Server (NTRS)
1971-01-01
The Langley Research Center is described, together with the nature of its activities, from which it can be seen that the Center is basically not a major pollution source. Geographical, geological, and climatic charateristics of the site are also described. inasmuch as they influence both the choice of disposal methods and the environmental effects of the pollutants. The known or probable pollution sources at the Center are described. Where the intensities of these sources might exceed the recommended guide-lines, the corrective actions that have been taken or are being taken are described. The entire inventory of pollution sources and control methods is summarized in an appendix.
An almost-parameter-free harmony search algorithm for groundwater pollution source identification.
Jiang, Simin; Zhang, Yali; Wang, Pei; Zheng, Maohui
2013-01-01
The spatiotemporal characterization of unknown sources of groundwater pollution is frequently encountered in environmental problems. This study adopts a simulation-optimization approach that combines a contaminant transport simulation model with a heuristic harmony search algorithm to identify unknown pollution sources. In the proposed methodology, an almost-parameter-free harmony search algorithm is developed. The performance of this methodology is evaluated on an illustrative groundwater pollution source identification problem, and the identified results indicate that the proposed almost-parameter-free harmony search algorithm-based optimization model can give satisfactory estimations, even when the irregular geometry, erroneous monitoring data, and prior information shortage of potential locations are considered.
40 CFR 415.534 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
... Nitrate Production Subcategory § 415.534 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart BA—Silver Nitrate Pollution or pollutant property...
40 CFR 415.534 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2011 CFR
2011-07-01
... Nitrate Production Subcategory § 415.534 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart BA—Silver Nitrate Pollution or pollutant property...
40 CFR 415.384 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
... Chloride Production Subcategory § 415.384 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart AL—Ferric Chloride Pollutant or pollutant property...
40 CFR 415.534 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2014 CFR
2014-07-01
... Nitrate Production Subcategory § 415.534 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart BA—Silver Nitrate Pollution or pollutant property...
40 CFR 415.534 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2013 CFR
2013-07-01
... Nitrate Production Subcategory § 415.534 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart BA—Silver Nitrate Pollution or pollutant property...
40 CFR 415.534 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2012 CFR
2012-07-01
... Nitrate Production Subcategory § 415.534 Pretreatment standards for existing sources (PSES). Except as... pretreatment standards for existing sources (PSES): Subpart BA—Silver Nitrate Pollution or pollutant property...
Moranda, Arianna
2017-01-01
A procedure for assessing harbour pollution by heavy metals and PAH and the possible sources of contamination is proposed. The procedure is based on a ratio-matching method applied to the results of principal component analysis (PCA), and it allows discrimination between point and nonpoint sources. The approach can be adopted when many sources of pollution can contribute in a very narrow coastal ecosystem, both internal and outside but close to the harbour, and was used to identify the possible point sources of contamination in a Mediterranean Harbour (Port of Vado, Savona, Italy). 235 sediment samples were collected in 81 sampling points during four monitoring campaigns and 28 chemicals were searched for within the collected samples. PCA of total samples allowed the assessment of 8 main possible point sources, while the refining ratio-matching identified 1 sampling point as a possible PAH source, 2 sampling points as Cd point sources, and 3 sampling points as C > 12 point sources. By a map analysis it was possible to assess two internal sources of pollution directly related to terminals activity. The study is the prosecution of a previous work aimed at assessing Savona-Vado Harbour pollution levels and suggested strategies to regulate the harbour activities. PMID:29270328
Paladino, Ombretta; Moranda, Arianna; Seyedsalehi, Mahdi
2017-01-01
A procedure for assessing harbour pollution by heavy metals and PAH and the possible sources of contamination is proposed. The procedure is based on a ratio-matching method applied to the results of principal component analysis (PCA), and it allows discrimination between point and nonpoint sources. The approach can be adopted when many sources of pollution can contribute in a very narrow coastal ecosystem, both internal and outside but close to the harbour, and was used to identify the possible point sources of contamination in a Mediterranean Harbour (Port of Vado, Savona, Italy). 235 sediment samples were collected in 81 sampling points during four monitoring campaigns and 28 chemicals were searched for within the collected samples. PCA of total samples allowed the assessment of 8 main possible point sources, while the refining ratio-matching identified 1 sampling point as a possible PAH source, 2 sampling points as Cd point sources, and 3 sampling points as C > 12 point sources. By a map analysis it was possible to assess two internal sources of pollution directly related to terminals activity. The study is the prosecution of a previous work aimed at assessing Savona-Vado Harbour pollution levels and suggested strategies to regulate the harbour activities.
MANAGING EXPOSURE TO INDOOR AIR POLLUTANTS IN RESIDENTIAL AND OFFICE ENVIRONMENTS
The paper discusses the factors to be considered in managing indoor air pollutants in residential and office environments to reduce occupant exposures. Techniques for managing indoor air pollution sources include: source elimination, substitution, modification, and pretreatment a...
40 CFR 461.45 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2014 CFR
2014-07-01
...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche.... (1) Subpart D—Foliar Battery Miscellaneous Wash—PSNS. Pollutant or pollutant property Maximum for any... shall be no discharge allowance for process wastewater pollutants from any battery manufacturing...
40 CFR 461.45 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2012 CFR
2012-07-01
...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche.... (1) Subpart D—Foliar Battery Miscellaneous Wash—PSNS. Pollutant or pollutant property Maximum for any... shall be no discharge allowance for process wastewater pollutants from any battery manufacturing...
40 CFR 461.45 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2013 CFR
2013-07-01
...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche.... (1) Subpart D—Foliar Battery Miscellaneous Wash—PSNS. Pollutant or pollutant property Maximum for any... shall be no discharge allowance for process wastewater pollutants from any battery manufacturing...
40 CFR 420.124 - New source performance standards (NSPS).
Code of Federal Regulations, 2010 CFR
2010-07-01
... GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Hot Coating Subcategory § 420.124...) Wire products and fasteners. Subpart L Pollutant or pollutant property New source performance standards...
40 CFR 420.86 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling... and wire. Subpart H Pollutant or pollutant property Pretreatment standards for new sources Maximum for...
40 CFR 420.86 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling... and wire. Subpart H Pollutant or pollutant property Pretreatment standards for new sources Maximum for...
40 CFR 420.124 - New source performance standards (NSPS).
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Hot Coating Subcategory § 420.124...) Wire products and fasteners. Subpart L Pollutant or pollutant property New source performance standards...
Pollution of water sources and removal of pollutants by advanced drinking-water treatment in China.
Wang, L; Wang, B
2000-01-01
The pollution of water resources and drinking water sources in China is described in this paper with basic data. About 90% of surface waters and over 60% of drinking water sources in urban areas have been polluted to different extents. The main pollutants present in drinking water sources are organic substances, ammonia nitrogen, phenols, pesticides and pathogenic micro-organisms, some of which cannot be removed effectively by the traditional water treatment processes like coagulation, sedimentation, filtration and chlorination, and the product water usually does not meet Chinese national drinking water standards, when polluted source water is treated. In some drinking-water plants in China, advanced treatment processes including activated carbon filtration and adsorption, ozonation, biological activated carbon and membrane separation have been employed for further treatment of the filtrate from a traditional treatment system producing unqualified drinking water, to make final product water meet the WHO guidelines and some developed countries' standards, as well as the Chinese national standards for drinking water. Some case studies of advanced water treatment plants are described in this paper as well.
A clustering algorithm for sample data based on environmental pollution characteristics
NASA Astrophysics Data System (ADS)
Chen, Mei; Wang, Pengfei; Chen, Qiang; Wu, Jiadong; Chen, Xiaoyun
2015-04-01
Environmental pollution has become an issue of serious international concern in recent years. Among the receptor-oriented pollution models, CMB, PMF, UNMIX, and PCA are widely used as source apportionment models. To improve the accuracy of source apportionment and classify the sample data for these models, this study proposes an easy-to-use, high-dimensional EPC algorithm that not only organizes all of the sample data into different groups according to the similarities in pollution characteristics such as pollution sources and concentrations but also simultaneously detects outliers. The main clustering process consists of selecting the first unlabelled point as the cluster centre, then assigning each data point in the sample dataset to its most similar cluster centre according to both the user-defined threshold and the value of similarity function in each iteration, and finally modifying the clusters using a method similar to k-Means. The validity and accuracy of the algorithm are tested using both real and synthetic datasets, which makes the EPC algorithm practical and effective for appropriately classifying sample data for source apportionment models and helpful for better understanding and interpreting the sources of pollution.
Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan
2015-01-01
Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. Igeo classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes. PMID:26690464
Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan
2015-12-11
Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index I(geo) and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. I(geo) classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.
Ma, Zhifei; Yang, Yu; Lian, Xinying; Jiang, Yonghai; Xi, Beidou; Peng, Xing; Yan, Kun
2016-09-01
The groundwater was sampled in a typical landfill area of the Northeast China. Coupled stable isotope and three dimensional excitation-emission matrix (3DEEM) were applied to dentify diffused NO3(-) inputs in the groundwater in this area. The results indicated that combined with the feature of groundwater hydrochemistry and three-dimensional fluorescence technology can effectively identify the nitrate pollution sources. The nitrate was derived from manure and sewage by δ(15)N and δ(18)O-NO3(-) values of groundwater in the different periods. The excitation-emission matrix fluorescence spectroscopy was further evidence of groundwater DOM mainly which comes from the landfill. The protein-like was very significant at the sampling points near the landfill (SPNL), but only fulvic acid-like appeared at downstream of the landfill groundwater sampling points (DLGSP) in the study area. Partial denitrification processes helped to attenuate nitrate concentration in anaerobic environment. Copyright © 2016 Elsevier B.V. All rights reserved.
Urban light pollution - The effect of atmospheric aerosols on astronomical observations at night
NASA Astrophysics Data System (ADS)
Joseph, J. H.; Kaufman, Y. J.; Mekler, Y.
1991-07-01
The transfer of diffuse city light from a localized source through a dust-laden atmosphere with optical depth less than 0.5 has been analyzed in the source-observer plane on the basis of an approximate treatment. The effect on several types of astronomical observation at night has been studied, considering different size distributions and amounts as well as particle shapes of the aerosols. The analysis is made in terms of the signal-to-noise ratios for a given amount of aerosol. The model is applied to conditions at the Wise Astronomical Observatory in the Negev desert, and limiting backgrounds for spectroscopy, photometry, and photography of stars and extended objects have been calculated for a variety of signal-to-noise ratios. Applications to observations with different equipment at various distances from an urban area of any size are possible. Due to the use of signal-to-noise ratios, the conclusions are different for the different experimental techniques used in astronomy.
Urban light pollution - The effect of atmospheric aerosols on astronomical observations at night
NASA Technical Reports Server (NTRS)
Joseph, Joachim H.; Mekler, Yuri; Kaufman, Yoram J.
1991-01-01
The transfer of diffuse city light from a localized source through a dust-laden atmosphere with optical depth less than 0.5 has been analyzed in the source-observer plane on the basis of an approximate treatment. The effect on several types of astronomical observation at night has been studied, considering different size distributions and amounts as well as particle shapes of the aerosols. The analysis is made in terms of the signal-to-noise ratios for a given amount of aerosol. The model is applied to conditions at the Wise Astronomical Observatory in the Negev desert, and limiting backgrounds for spectroscopy, photometry, and photography of stars and extended objects have been calculated for a variety of signal-to-noise ratios. Applications to observations with different equipment at various distances from an urban area of any size are possible. Due to the use of signal-to-noise ratios, the conclusions are different for the different experimental techniques used in astronomy.
40 CFR 420.134 - New source performance standards (NSPS).
Code of Federal Regulations, 2010 CFR
2010-07-01
... Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg. 1 TSS 0.00998 0.00465... operations. Subpart M—New Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg...
40 CFR 420.134 - New source performance standards (NSPS).
Code of Federal Regulations, 2011 CFR
2011-07-01
... Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg. 1 TSS 0.00998 0.00465... operations. Subpart M—New Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg...
Variations of pollution sources of Cu in Jiaozhou Bay 1982-1986
NASA Astrophysics Data System (ADS)
Yang, Dongfang; Li, Haixia; Wang, Qi; Ding, Jun; Zhang, Longlei
2017-12-01
Cu pollution in marine bays has been one of the critical environmental issues in the whole world, and understanding the variations of the pollution sources is essential to environmental protection. This paper identified the sources of Cu in Jiaozhou Bay during 1982-1986, and revealed the variations of the sources. Results showed that there were five Cu sources during study years including marine current, stream flow, island top, overland runoff and marine traffic, respectively, whose source strengths were varying from 0.39-20.60 μg L-1, 0.37-10.57 μg L-1, 0.77-4.86 μg L-1, 2.28-3.56 μg L-1, 9.48 μg L-1, respectively. These findings were helpful information in decision-making of pollution control and environmental remediation practice.
40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 15 2013-07-01 2013-07-01 false Test Methods Pollutant Measurement... POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) Pt. 63, App. A Appendix A to Part 63—Test Methods Pollutant... analyte spiking? 13.0How do I conduct tests at similar sources? Optional Requirements 14.0How do I use and...
40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Test Methods Pollutant Measurement... POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) Pt. 63, App. A Appendix A to Part 63—Test Methods Pollutant... analyte spiking? 13.0How do I conduct tests at similar sources? Optional Requirements 14.0How do I use and...
40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Test Methods Pollutant Measurement... POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) Pt. 63, App. A Appendix A to Part 63—Test Methods Pollutant... analyte spiking? 13.0How do I conduct tests at similar sources? Optional Requirements 14.0How do I use and...
40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Test Methods Pollutant Measurement... POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) Pt. 63, App. A Appendix A to Part 63—Test Methods Pollutant... analyte spiking? 13.0How do I conduct tests at similar sources? Optional Requirements 14.0How do I use and...
40 CFR 63.1217 - What are the standards for liquid fuel boilers that burn hazardous waste?
Code of Federal Regulations, 2010 CFR
2010-07-01
... ng TEQ/dscm, corrected to 7 percent oxygen, for liquid fuel boilers equipped with a dry air pollution... by paragraph (a)(5) of this section for sources not equipped with a dry air pollution control system; (iii) A source equipped with a wet air pollution control system followed by a dry air pollution control...
40 CFR 63.1217 - What are the standards for liquid fuel boilers that burn hazardous waste?
Code of Federal Regulations, 2011 CFR
2011-07-01
... ng TEQ/dscm, corrected to 7 percent oxygen, for liquid fuel boilers equipped with a dry air pollution... by paragraph (a)(5) of this section for sources not equipped with a dry air pollution control system; (iii) A source equipped with a wet air pollution control system followed by a dry air pollution control...
Numerical simulation of hydrodynamic and water quality effects of shoreline changes in Bohai Bay
NASA Astrophysics Data System (ADS)
Jia, Han; Shen, Yongming; Su, Meirong; Yu, Chunxue
2018-02-01
This study uses the HD and Ecolab modules of MIKE to simulate the hydrodynamic and water quality and predict the influence of shoreline changes in Bohai Bay, China. The study shows that shoreline changes weaken the residual current and generate a counter-clockwise circulation south of Huanghua Port, thereby resulting in weak water exchange capacity and low pollutant-diffusing capacity. Shoreline changes reduce the area of Bohai Bay, resulting in a smaller tidal prism and further weakening the water exchange capacity. This situation is not conducive to the diffusion of pollutants, and therefore may lead to increased water pollution in the bay. Shoreline changes hinder the spread of runoff, weaken the dilution effect of the river on seawater, and block the spread of coastal residual current, thereby resulting in increased salinity near the reclamation area. Shoreline changes lead to an increase in PO4-P concentration and decrease in DIN concentration. The value of N/P near the project decreases, thereby weakening the phosphorus-limited effect.
EMISSIONS PROFILE CHARACTERIZATION OF LAKE MICHIGAN POLLUTANT SOURCES - PART II
The southern Lake Michigan area continues to experience poor air quality despite the implementation of many measures to control particulate matter, ozone and toxic pollutants. Fortunately, the ambient atmosphere holds clues to these sources and their contributions to urban pollut...
DOT National Transportation Integrated Search
2017-06-19
Transportation-related emissions are a major source of air pollution in many urban areas. Human exposure to this pollution is related to their proximity to major roadways, yet federal and state Environmental Protection Agencies (EPAs) conduct regulat...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-21
... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY: Environmental Protection... Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance...
On - road mobile source pollutant emissions : identifying hotspots and ranking roads.
DOT National Transportation Integrated Search
2010-12-30
A considerable amount of pollution to the air in the forms of hydrocarbons, carbon : monoxide (CO), nitrogen oxides (NOx), particulate matter (PM) and air toxics comes : from the on-road mobile sources. Estimation of the emissions of these pollutants...
40 CFR 461.43 - New source performance standards (NSPS).
Code of Federal Regulations, 2012 CFR
2012-07-01
... GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche Subcategory § 461... Battery Miscellaneous Wash—NSPS. Pollutant or pollutant property Maximum for any 1 day Maximum for monthly... process wastewater pollutants from any battery manufacturing operation other than those battery...
40 CFR 461.43 - New source performance standards (NSPS).
Code of Federal Regulations, 2013 CFR
2013-07-01
... GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche Subcategory § 461... Battery Miscellaneous Wash—NSPS. Pollutant or pollutant property Maximum for any 1 day Maximum for monthly... process wastewater pollutants from any battery manufacturing operation other than those battery...
40 CFR 461.43 - New source performance standards (NSPS).
Code of Federal Regulations, 2014 CFR
2014-07-01
... GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Leclanche Subcategory § 461... Battery Miscellaneous Wash—NSPS. Pollutant or pollutant property Maximum for any 1 day Maximum for monthly... process wastewater pollutants from any battery manufacturing operation other than those battery...
40 CFR 63.8794 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible... operate and maintain your affected source, including air pollution control and monitoring equipment...
Yassin, Mohamed F; Ohba, Masaake
2012-09-01
To assist validation of numerical simulations of urban pollution, air quality in a street canyon was investigated using a wind tunnel as a research tool under neutral atmospheric conditions. We used tracer gas techniques from a line source without buoyancy. Ethylene (C(2)H(4)) was used as the tracer gas. The street canyon model was formed of six parallel building rows of the same length. The flow and dispersion field was analyzed and measured using a hot-wire anemometer with split fiber probe and fast flame ionization detector. The diffusion flow field in the boundary layer within the street canyon was examined at different locations, with varying building orientations (θ=90°, 112.5°, 135° and 157.5°) and street canyon aspect ratios (W/H=1/2, 3/4 and 1) downwind of the leeward side of the street canyon model. Results show that velocity increases with aspect ratio, and with θ>90°. Pollutant concentration increases as aspect ratio decreases. This concentration decreases exponentially in the vertical direction, and decreases as θ increases from 90°. Measured pollutant concentration distributions indicate that variability of building orientation and aspect ratio in the street canyon are important for estimating air quality in the canyon. The data presented here can be used as a comprehensive database for validation of numerical models.
NASA Technical Reports Server (NTRS)
Pawson, Steven; Zhu, Z.; Ott, L. E.; Molod, A.; Duncan, B. N.; Nielsen, J. E.
2009-01-01
Sub-grid transport, by convection and turbulence, is known to play an important role in lofting pollutants from their source regions. Consequently, the long-range transport and climatology of simulated atmospheric composition are impacted. This study uses the Goddard Earth Observing System, Version 5 (GEOS-5) atmospheric model to study pollutant transport. The baseline model uses a Relaxed Arakawa-Schubert (RAS) scheme that represents convection through a sequence of linearly entraining cloud plumes characterized by unique detrainment levels. Thermodynamics, moisture and trace gases are transported in the same manner. Various approximate forms of trace-gas transport are implemented, in which the box-averaged cloud mass fluxes from RAS are used with different numerical approaches. Substantial impacts on forward-model simulations of CO (using a linearized chemistry) are evident. In particular, some aspects of simulations using a diffusive form of sub-grid transport bear more resemblance to space-biased CO observations than do the baseline simulations with RAS transport. Implications for transport in the real atmosphere will be discussed. Another issue of importance is that many adjoint/inversion computations use simplified representations of sub-grid transport that may be inconsistent with the forward models: implications will be discussed. Finally, simulations using a complex chemistry model in GEOS-5 (in place of the linearized CO model) are underway: noteworthy results from this simulation will be mentioned.
Li, Lei; Wang, Tie-yu; Wang, Xiaojun; Xiao, Rong-bo; Li, Qi-feng; Peng, Chi; Han, Cun-liang
2016-04-15
Based on comprehensive consideration of soil environmental quality, pollution status of river, environmental vulnerability and the stress of pollution sources, a technical method was established for classification of priority area of soil environmental protection around the river-style water sources. Shunde channel as an important drinking water sources of Foshan City, Guangdong province, was studied as a case, of which the classification evaluation system was set up. In detail, several evaluation factors were selected according to the local conditions of nature, society and economy, including the pollution degree of heavy metals in soil and sediment, soil characteristics, groundwater sensitivity, vegetation coverage, the type and location of pollution sources. Data information was mainly obtained by means of field survey, sampling analysis, and remote sensing interpretation. Afterwards, Analytical Hierarchy Process (AHP) was adopted to decide the weight of each factor. The basic spatial data layers were set up respectively and overlaid based on the weighted summation assessment model in Geographical Information System (GIS), resulting in a classification map of soil environmental protection level in priority area of Shunde channel. Accordingly, the area was classified to three levels named as polluted zone, risky zone and safe zone, which respectively accounted for 6.37%, 60.90% and 32.73% of the whole study area. Polluted zone and risky zone were mainly distributed in Lecong, Longjiang and Leliu towns, with pollutants mainly resulted from the long-term development of aquaculture and the industries containing furniture, plastic constructional materials and textile and clothing. In accordance with the main pollution sources of soil, targeted and differentiated strategies were put forward. The newly established evaluation method could be referenced for the protection and sustainable utilization of soil environment around the water sources.
Chen, Wenjun; He, Bin; Nover, Daniel; Duan, Weili; Luo, Chuan; Zhao, Kaiyan; Chen, Wen
2018-01-01
Excessive nitrogen (N) discharge from agriculture causes widespread problems in aquatic ecosystems. Knowledge of spatiotemporal patterns and source attribution of N pollution is critical for nutrient management programs but is poorly studied in headwaters with various small water bodies and mini-point pollution sources. Taking a typical small watershed in the low mountains of Southeastern China as an example, N pollution and source attribution were studied for a multipond system around a village using the Hydrological Simulation Program-Fortran (HSPF) model. The results exhibited distinctive spatio-seasonal variations with an overall seriousness rank for the three indicators: total nitrogen (TN) > nitrate/nitrite nitrogen (NO x - -N) > ammonia nitrogen (NH 3 -N), according to the Chinese Surface Water Quality Standard. TN pollution was severe for the entire watershed, while NO x - -N pollution was significant for ponds and ditches far from the village, and the NH 3 -N concentrations were acceptable except for the ponds near the village in summer. Although food and cash crop production accounted for the largest source of N loads, we discovered that mini-point pollution sources, including animal feeding operations, rural residential sewage, and waste, together contributed as high as 47% of the TN and NH 3 -N loads in ponds and ditches. So, apart from eco-fertilizer programs and concentrated animal feeding operations, the importance of environmental awareness building for resource management is highlighted for small farmers in headwater agricultural watersheds. As a first attempt to incorporate multipond systems into the process-based modeling of nonpoint source (NPS) pollution, this work can inform other hydro-environmental studies on scattered and small water bodies. The results are also useful to water quality improvement for entire river basins.
Zhang, Bao-Lei; Cui, Bo-Hao; Zhang, Shu-Min; Wu, Quan-Yuan; Yao, Lei
2018-05-03
Nitrogen (N) and phosphorus (P) from non-point source (NPS) pollution in Nansi Lake Basin greatly influenced the water quality of Nansi Lake, which is the determinant factor for the success of East Route of South-North Water Transfer Project in China. This research improved Johnes export coefficient model (ECM) by developing a method to determine the export coefficients of different land use types based on the hydrological and water quality data. Taking NPS total nitrogen (TN) and total phosphorus (TP) as the study objects, this study estimated the contributions of different pollution sources and analyzed their spatial distributions based on the improved ECM. The results underlined that the method for obtaining output coefficients of land use types using hydrology and water quality data is feasible and accurate, and is suitable for the study of NPS pollution at large-scale basins. The average output structure of NPS TN from land use, rural breeding and rural life is 33.6, 25.9, and 40.5%, and the NPS TP is 31.6, 43.7, and 24.7%, respectively. Especially, dry land was the main land use source for both NPS TN and TP pollution, with the contributed proportions of 81.3 and 81.8% respectively. The counties of Zaozhuang, Tengzhou, Caoxian, Yuncheng, and Shanxian had higher contribution rates and the counties of Dingtao, Juancheng, and Caoxian had the higher load intensities for both NPS TN and TP pollution. The results of this study allowed for an improvement in the understanding of the pollution source contribution and enabled researchers and planners to focus on the most important sources and regions of NPS pollution.
The most serious problem facing mankind on Pb pollution
NASA Astrophysics Data System (ADS)
Yang, Dongfang; Miao, Zhenqing; Li, Haixia; Zhang, Xiaolong; Wang, Qi
2017-12-01
Pb pollution is one of the most critical environmental issues in the world. This paper analyzed the content, pollution level and pollution source of Pb in Jiaozhou Bay based on investigation data in surface waters in 1987. Results showed that Pb contents in surface waters in May, July and November 1987 were 1.95-7.96 μg L-1, 5.02-61.61 μg L-1 and 3.98-24.64 μg L-1, respectively, and the pollution levels were moderate, heavy and relative heavy, respectively. The major Pb sources in this bay were river flow and marine current, whose source strengths could be as high as 61.61 μg L-1and 24.64 μg L-1, respectively. The pollution level of Pb in Jiaozhou Bay was serious enough in 1987, and the pollution control and environmental remediation were necessary.
40 CFR 63.1650 - Applicability and compliance dates.
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission... are major sources or are co-located at major sources of hazardous air pollutant emissions. (b) The following sources at a ferromanganese and silicomanganese production facility are subject to this subpart...
Atmospheric deposition having been one of the major source of Pb in Jiaozhou Bay
NASA Astrophysics Data System (ADS)
Yang, Dongfang; Miao, Zhenqing; Zhang, Xiaolong; Wang, Qi; Li, Haixia
2018-03-01
Many marine bays have been polluted by Pb due to the rapid development of industry, and identifying the major source of Pb is essential to pollution control. This paper analyzed the distribution and pollution source of Pb in Jiaozhou Bay in 1988. Results showed that Pb contents in surface waters in Jiaozhou Bay in April, July and October 1988 were 5.52-24.61 μg L‑1, 7.66-38.62 μg L‑1 and 6.89-19.30 μg L‑1, respectively. The major Pb sources in this bay were atmospheric deposition, and marine current, whose source strengths were 19.30-24.61μg L‑1 and 38.62 μg L‑1, respectively. Atmospheric deposition had been one of the major Pb sources in Jiaozhou Bay, and the source strengths were stable and strong. The pollution level of Pb in this bay in 1988 was moderate to heavy, and the source control measurements were necessary.
The Escompte Programme: An Overview of The Field Experiment
NASA Astrophysics Data System (ADS)
Durand, P.; Cros, B.; Peuch, V. H.; Kottmeier, C.; Saïd, F.; Perros, P.; Robin, D.
The ESCOMPTE programme (http://medias.obs-mip.fr/escompte) is embedded in a long-term strategy whose aim is the improvement of air quality. In order to be able to take preventive measures to reduce the size and the effects of pollution events, we need to dispose of efficient tools of prediction of these events. Such tools, yet to be developed or improved, are, on the one hand, the inventory of the various pollu- tion sources (fixed and mobile), and, on the other hand, mathematical models able to accurately simulate the dynamical (diffusion and transport) and chemical (reactions) processes under which the various solid, liquid and gaseous species will evolve. The main objective of the ESCOMPTE programme is to gather a data set of some pollution events, involving the emissions of primary pollutants, as well as atmospheric dynam- ics and chemistry. This data set, acquired at the surface and in the lower troposphere, in a region located South-East of France, between June 4th and July 16th, 2001, will serve as a reference for qualifying the CTMs of atmospheric pollution, from local- to regional-scale. A 120km*120km area, around the "Marseille-Berre" site, in the South-eastern of France, has been selected to host the ESCOMPTE field campaign. This region presents a high occurrence of photochemical pollution, because it is one of the most sunny re- gions of France, with anticyclonic conditions prevailing during summer ; it involves the urbanized area of Marseille city (more than one million people), and the "Fos- Berre" industrial area (oil refineries, power plants, E), both being considerable sources of various pollutants ; it presents terrain characteristics (land-sea-breeze circulations ; numerous hills and mountain chains up to more than thousand meters high) acting as dynamical forcings on the transport of pollutants. Although the core domain of ESCOMPTE is a 100km*100km box, a hierarchy of chemistry and/or transport models is involved in the programme, and is able do de- scribe the various scales, from the global one, up to the local transport within the urban canopy of Marseille. During the period from June 12, to July 13, 5 pollution episodes (IOPs 1, 2a, 2b, 3 and 4) were documented by a large set of instruments, involving six aircraft (five of them equipped for in situ meteorological and chemical measurements, and the sixth with the Doppler lidar WIND), five ozone lidars, 14 wind profilers (sodars and radars), one 1 Doppler scanning lidar, three radiosonde systems, a network of 15 ground stations, equipped for chemistry and/or surface flux measurements, 2 instrumented ships and constant volume balloons. 2
Space-Time Urban Air Pollution Forecasts
NASA Astrophysics Data System (ADS)
Russo, A.; Trigo, R. M.; Soares, A.
2012-04-01
Air pollution, like other natural phenomena, may be considered a space-time process. However, the simultaneous integration of time and space is not an easy task to perform, due to the existence of different uncertainties levels and data characteristics. In this work we propose a hybrid method that combines geostatistical and neural models to analyze PM10 time series recorded in the urban area of Lisbon (Portugal) for the 2002-2006 period and to produce forecasts. Geostatistical models have been widely used to characterize air pollution in urban areas, where the pollutant sources are considered diffuse, and also to industrial areas with localized emission sources. It should be stressed however that most geostatistical models correspond basically to an interpolation methodology (estimation, simulation) of a set of variables in a spatial or space-time domain. The temporal prediction of a pollutant usually requires knowledge of the main trends and complex patterns of physical dispersion phenomenon. To deal with low resolution problems and to enhance reliability of predictions, an approach based on neural network short term predictions in the monitoring stations which behave as a local conditioner to a fine grid stochastic simulation model is presented here. After the pollutant concentration is predicted for a given time period at the monitoring stations, we can use the local conditional distributions of observed values, given the predicted value for that period, to perform the spatial simulations for the entire area and consequently evaluate the spatial uncertainty of pollutant concentration. To attain this objective, we propose the use of direct sequential simulations with local distributions. With this approach one succeed to predict the space-time distribution of pollutant concentration that accounts for the time prediction uncertainty (reflecting the neural networks efficiency at each local monitoring station) and the spatial uncertainty as revealed by the spatial variograms. The dataset used consists of PM10 concentrations recorded hourly by 12 monitoring stations within the Lisbon's area, for the period 2002-2006. In addition, meteorological data recorded at 3 monitoring stations and boundary layer height (BLH) daily values from the ECMWF (European Centre for Medium Weather Forecast), ERA Interim, were also used. Based on the large-scale standard pressure fields from the ERA40/ECMWF, prevailing circulation patterns at regional scale where determined and used on the construction of the models. After the daily forecasts were produced, the difference between the average maps based on real observations and predicted values were determined and the model's performance was assessed. Based on the analysis of the results, we conclude that the proposed approach shows to be a very promising alternative for urban air quality characterization because of its good results and simplicity of application.
40 CFR 421.196 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Electrolyte. PSNS for the Secondary Indium Subcategory Pollutant or pollutant property Maximum for any 1 day... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Indium Subcategory... wastewater pollutants in secondary indium process wastewater introduced into a POTW should not exceed the...
40 CFR 421.196 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Electrolyte. PSNS for the Secondary Indium Subcategory Pollutant or pollutant property Maximum for any 1 day... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Indium Subcategory... wastewater pollutants in secondary indium process wastewater introduced into a POTW should not exceed the...
40 CFR 430.55 - New source performance standards (NSPS).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) The following standards apply to all new sources in the calcium-, magnesium-, or sodium-based sulfite pulp segment: Subpart E [Production of Calcium-, Magnesium-, or Sodium-based Sulfite Pulps] Pollutant... apply to non-continuous dischargers: Subpart E [Supplemental NSPS] Pollutant or pollutant property...
40 CFR 430.55 - New source performance standards (NSPS).
Code of Federal Regulations, 2014 CFR
2014-07-01
...) The following standards apply to all new sources in the calcium-, magnesium-, or sodium-based sulfite pulp segment: Subpart E [Production of Calcium-, Magnesium-, or Sodium-based Sulfite Pulps] Pollutant... apply to non-continuous dischargers: Subpart E [Supplemental NSPS] Pollutant or pollutant property...
40 CFR 430.55 - New source performance standards (NSPS).
Code of Federal Regulations, 2013 CFR
2013-07-01
...) The following standards apply to all new sources in the calcium-, magnesium-, or sodium-based sulfite pulp segment: Subpart E [Production of Calcium-, Magnesium-, or Sodium-based Sulfite Pulps] Pollutant... apply to non-continuous dischargers: Subpart E [Supplemental NSPS] Pollutant or pollutant property...
40 CFR 430.55 - New source performance standards (NSPS).
Code of Federal Regulations, 2011 CFR
2011-07-01
...) The following standards apply to all new sources in the calcium-, magnesium-, or sodium-based sulfite pulp segment: Subpart E [Production of Calcium-, Magnesium-, or Sodium-based Sulfite Pulps] Pollutant... apply to non-continuous dischargers: Subpart E [Supplemental NSPS] Pollutant or pollutant property...
40 CFR 430.55 - New source performance standards (NSPS).
Code of Federal Regulations, 2012 CFR
2012-07-01
...) The following standards apply to all new sources in the calcium-, magnesium-, or sodium-based sulfite pulp segment: Subpart E [Production of Calcium-, Magnesium-, or Sodium-based Sulfite Pulps] Pollutant... apply to non-continuous dischargers: Subpart E [Supplemental NSPS] Pollutant or pollutant property...
EPA is proposing to approve revisions to the Northern Sonoma County Air Pollution Control District (NSCAPCD) portion of the California SIP concerning NSCAPCD's PSD permitting program for new and modified sources of air pollution.
40 CFR 421.96 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Metallurgical Acid Plants... wastewater pollutants in metallurgical acid plant blowdown introduced into a POTW shall not exceed the following values: Subpart I—Metallurgical Acid Plant—PSNS Pollutant or pollutant property Maximum for any 1...
40 CFR 421.96 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Metallurgical Acid Plants... wastewater pollutants in metallurgical acid plant blowdown introduced into a POTW shall not exceed the following values: Subpart I—Metallurgical Acid Plant—PSNS Pollutant or pollutant property Maximum for any 1...
40 CFR 420.46 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2014 CFR
2014-07-01
... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...
40 CFR 420.46 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2013 CFR
2013-07-01
... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...
40 CFR 420.46 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2011 CFR
2011-07-01
... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...
40 CFR 420.46 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2012 CFR
2012-07-01
... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...