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Cincinnati, OH, United States

Michael-Kordatou I.,University of Cyprus | Michael C.,University of Cyprus | Duan X.,University of Cyprus | Duan X.,University of Cincinnati | And 6 more authors.
Water Research | Year: 2015

Wastewater reuse is currently considered globally as the most critical element of sustainable water management. The dissolved effluent organic matter (dEfOM) present in biologically treated urban wastewater, consists of a heterogeneous mixture of refractory organic compounds with diverse structures and varying origin, including dissolved naturalorganic matter, soluble microbial products, endocrine disrupting compounds, pharmaceuticals and personal care products residues, disinfection by-products, metabolites/transformation products and others, which can reach the aquatic environment through discharge and reuse applications. dEfOM constitutes the major fraction of the effluent organic matter (EfOM) and due to its chemical complexity, it is necessary to utilize a battery of complementary techniques to adequately describe its structural and functional character. dEfOM has been shown to exhibit contrasting effects towards various aquatic organisms. It decreases metal uptake, thus potentially reducing their bioavailability to exposed organisms. On the other hand, dEfOM can be adsorbed on cell membranes inducing toxic effects. This review paper evaluates the performance of various advanced treatment processes (i.e., membrane filtration and separation processes, activated carbon adsorption, ion-exchange resin process, and advanced chemical oxidation processes) in removing dEfOM from wastewater effluents. In general, the literature findings reveal that dEfOM removal by advanced treatment processes depends on the type and the amount of organic compounds present in the aqueous matrix, as well asthe operational parameters and the removal mechanisms taking place during the application of each treatment technology. © 2015 Elsevier Ltd. Source

Graney J.R.,Binghamton University State University of New York | Landis M.S.,Us Epa Office Of Research And Development
Science of the Total Environment | Year: 2013

A technique that couples lead (Pb) isotopes and multi-element concentrations with meteorological analysis was used to assess source contributions to precipitation samples at the Bondville, Illinois USA National Trends Network (NTN) site. Precipitation samples collected over a 16. month period (July 1994-October 1995) at Bondville were parsed into six unique meteorological flow regimes using a minimum variance clustering technique on back trajectory endpoints. Pb isotope ratios and multi-element concentrations were measured using high resolution inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) on the archived precipitation samples. Bondville is located in central Illinois, ~. 250. km downwind from smelters in southeast Missouri. The Mississippi Valley Type ore deposits in Missouri provided a unique multi-element and Pb isotope fingerprint for smelter emissions which could be contrasted to industrial emissions from the Chicago and Indianapolis urban areas (~. 125. km north and east, of Bondville respectively) and regional emissions from electric utility facilities. Differences in Pb isotopes and element concentrations in precipitation corresponded to flow regime. Industrial sources from urban areas, and thorogenic Pb from coal use, could be differentiated from smelter emissions from Missouri by coupling Pb isotopes with variations in element ratios and relative mass factors. Using a three endmember mixing model based on Pb isotope ratio differences, industrial processes in urban airsheds contributed 56 ± 19%, smelters in southeast Missouri 26 ± 13%, and coal combustion 18 ± 7%, of the Pb in precipitation collected in Bondville in the mid-1990s. © 2012 Elsevier B.V. Source

Vanderhoof M.K.,U.S. Geological Survey | Alexander L.C.,Us Epa Office Of Research And Development | Todd M.J.,Us Epa Office Of Research And Development
Landscape Ecology | Year: 2016

Context: Quantifying variability in landscape-scale surface water connectivity can help improve our understanding of the multiple effects of wetlands on downstream waterways. Objectives: We examined how wetland merging and the coalescence of wetlands with streams varied both spatially (among ecoregions) and interannually (from drought to deluge) across parts of the Prairie Pothole Region. Methods: Wetland extent was derived over a time series (1990–2011) using Landsat imagery. Changes in landscape-scale connectivity, generated by the physical coalescence of wetlands with other surface water features, were quantified by fusing static wetland and stream datasets with Landsat-derived wetland extent maps, and related to multiple wetness indices. The usage of Landsat allows for decadal-scale analysis, but limits the types of surface water connections that can be detected. Results: Wetland extent correlated positively with the merging of wetlands and wetlands with streams. Wetness conditions, as defined by drought indices and runoff, were positively correlated with wetland extent, but less consistently correlated with measures of surface water connectivity. The degree of wetland–wetland merging was found to depend less on total wetland area or density, and more on climate conditions, as well as the threshold for how wetland/upland was defined. In contrast, the merging of wetlands with streams was positively correlated with stream density, and inversely related to wetland density. Conclusions: Characterizing the degree of surface water connectivity within the Prairie Pothole Region in North America requires consideration of (1) climate-driven variation in wetness conditions and (2) within-region variation in wetland and stream spatial arrangements. © 2015, The Author(s). Source

Patterson C.L.,Us Epa Office Of Research And Development | Adams J.Q.,Us Epa Office Of Research And Development
Frontiers of Earth Science | Year: 2011

Natural disasters can be devastating to local water supplies affecting millions of people. Disaster recovery plans and water industry collaboration during emergencies protect consumers from contaminated drinking water supplies and help facilitate the repair of public water systems. Prior to an event, utilities and municipalities can use "What if"? scenarios to develop emergency operation, response, and recovery plans designed to reduce the severity of damage and destruction. Government agencies including the EPA are planning ahead to provide temporary supplies of potable water and small drinking water treatment technologies to communities as an integral part of emergency response activities that will ensure clean and safe drinking water. © 2011 Higher Education Press and Springer-Verlag Berlin Heidelberg. Source

Paulot F.,Harvard University | Jacob D.J.,Harvard University | Pinder R.W.,Us Epa Office Of Research And Development | Bash J.O.,Us Epa Office Of Research And Development | And 2 more authors.
Journal of Geophysical Research: Atmospheres | Year: 2014

We use the adjoint of a global 3-D chemical transport model (GEOS-Chem) to optimize ammonia (NH3) emissions in the U.S., European Union, and China by inversion of 2005-2008 network data for NH4+ wet deposition fluxes. Optimized emissions are derived on a 2° × 2.5° grid for individual months and years. Error characterization in the optimization includes model errors in precipitation. Annual optimized emissions are 2.8 Tg NH3-N a-1 for the contiguous U.S., 3.1 Tg NH3-N a-1 for the European Union, and 8.4 Tg NH3-N a-1 for China. Comparisons to previous inventories for the U.S. and European Union show consistency (∼±15%) in annual totals but some large spatial and seasonal differences. We develop a new global bottom-up inventory of NH3 emissions (Magnitude And Seasonality of Agricultural Emissions model for NH3 (MASAGE-NH3)) to interpret the results of the adjoint optimization. MASAGE-NH3 provides information on the magnitude and seasonality of NH3 emissions from individual crop and livestock sources on a 0.5° × 0.5° grid. We find that U.S. emissions peak in the spring in the Midwest due to corn fertilization and in the summer elsewhere due to manure. The seasonality of European emissions is more homogeneous with a well-defined maximum in spring associated with manure and mineral fertilizer application. There is some evidence for the effect of European regulations of NH3 emissions, notably a large fall decrease in northern Europe. Emissions in China peak in summer because of the summertime application of fertilizer for double cropping. Key Points Adjoint-based inversion of ammonium wet deposition in the U.S., Europe, and ChinaMuch larger spatial and temporal variability of U.S. emission than in the a prioriNew model of NH3 emissions reproduces the patterns of the optimized emissions. ©2014. American Geophysical Union. All Rights Reserved. Source

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