Influence of organic carbon loading, sediment associated metal oxide content and sediment grain size distributions upon Cryptosporidium parvum removal during riverbank filtration operations, Sonoma County, CA
TL;DR: Although the grain-surface metal oxides were found to have a high colloid-removal capacity, this study suggested that any major changes within the watershed that would result in long-term alterations in either the quantity and (or) the character of the river's DOC could alter the effectiveness of pathogen removal during RBF operations.
About: This article is published in Water Research.The article was published on 2010-02-01. It has received 27 citations till now. The article focuses on the topics: Dissolved organic carbon & Organic matter.
Citations
More filters
01 Jan 2011
TL;DR: In this paper, a Mnoxide doped gel probe sampler was developed to study in situ rates of reductive dissolution and was validated with laboratory studies with ascorbic acid and Shewanella oneidensis MR-1 as model reductants.
Abstract: This study investigated the cycling of Mn and Fe as oxic surface water entered shallow sediments and was reduced, and as reduced groundwater became exposed to oxygen and was oxidized. A Mn-oxide doped gel probe sampler was developed to study in situ rates of reductive dissolution and was validated with laboratory studies with ascorbic acid and Shewanella oneidensis MR-1 as model reductants. The sampler was deployed in the bank sediments of Lake Tegel, Berlin, Germany. Modeling of the diffusion-controlled reaction converted the mass loss from the gels in the sampler to a profile of pseudo-first-order rate constants as a function of depth. The rate constants were highest at depths with high dissolved Fe and low operationally defined fractions of reducible oxides of Fe and Mn in the sediments. A laboratory column experiment showed that 1.3-m water table fluctuations, as observed in bank filtration sites around Berlin, were able to provide sufficient dissolved oxygen delivery for Pseudomonas putida GB-1, an obligate aerobe, to oxidize Mn(II) in situ. Accumulation of Mn on the quartz sand in the column at the end of the experiment was limited to the top 60 cm, as measured with X-ray fluorescence (XRF), and X-ray absorption spectroscopy (XAS) analysis confirmed that the solid formed was a Mn(IV) oxide characteristic of biogenic origin. After a period of “filter ripening” in the column, rates of in situ oxidation were still lower than rates in engineered aerated sand filters. Adjacent to a production well with a water table that fluctuates up to 7 m annually at Lake Tegel, however, sediments collected from a borehole did not show any significant accumulation of Mn or Fe with depth, as measured by XRF; analysis of the speciation of Mn and Fe in the solid phase by XAS suggested a slight increase in the proportions of total Mn as Mn(II) and of total Fe as Fe(II) with depth. At this location, vertical zonation of groundwater may preclude the co-occurrence of reduced Mn and Fe with dissolved oxygen entrapped by water table fluctuations. Whether groundwater changes from oxidizing to reducing conditions or vice versa, the behavior of Mn and Fe reflects a complex interaction between sediments, solutes, microbial activity, and hydrology.
4 citations
3 citations
01 Jul 2013
TL;DR: In this paper, the authors used quantitative microbial risk analysis (QMRA) models to assess the relation between microbial concentrations in drinking waters and public health, and provided a risk calculation output that accurately estimate the actual risk of infection associated to these protozoan parasites.
Abstract: RESUME Le traitement de l’eau potable a comme principale mission de proteger la sante publique. En absence d’eclosion de maladies d’origine hydrique, il est difficile d’etablir le lien entre la consommation d’eau potable et le risque d’infection de la population desservie (Teunis & Havelaar 2002). Dans ces circonstances, les modeles d’analyse quantitative du risque microbien (QMRA) permettent d’evaluer la relation entre les concentrations de microorganismes pathogenes a la source, le traitement et la distribution des eaux potables et la sante publique (Regli et al. 1991, Teunis et al. 1997). Dans une approche multi-barrieres du traitement des eaux potables, la description de la performance de chacun des procedes d’une filiere de traitement est consideree lors de l’evaluation de l’exposition (Medema & Ashbolt 2006). Actuellement, la plupart des usines canadiennes desservies par des eaux de surface misent sur l’operation de procedes de filtration granulaire afin d’atteindre les objectifs de traitement en matiere de Cryptosporidium et Giardia imposes par la reglementation. Dans ce contexte, il est necessaire de decrire la performance de ces procedes avec precision afin de pouvoir generer un calcul qui reflete le risque reel d’infection a ces protozoaires parasites. De plus, afin de mieux comprendre les parametres qui contribuent aux variations de performance de procedes de filtration, il est d’interet de combler les lacunes en ce qui concerne l’influence des variations de qualite d’eau brute et de l’impact des caracteristiques des materiaux filtrants sur l’enlevement de Cryptosporidium et Giardia par filtration granulaire. L’objectif general de ce projet d’etudes doctorales est de comprendre le role (i) du vieillissement des materiaux filtrants et (ii) de la nature des particules a l’eau brute sur l’enlevement de protozoaires parasites par filtration granulaire.----------ABSTRACT The primary role of drinking water treatment is to protect public health. In the absence of waterborne outbreaks, it is difficult to assess the health risk associated with drinking water consumption (Teunis & Havelaar 2002). In such circumstances, quantitative microbial risk analysis (QMRA) models may be used to assess the relation between microbial concentrations in drinking waters and public health (Regli et al. 1991, Teunis et al. 1997). In a multi-barrier approach to drinking water treatment, process performance of each treatment step contribute to the exposure assessment (Medema & Ashbolt 2006). As most Canadian water treatment plants fed with surface water currently rely on granular filtration processes to meet Cryptosporidium and Giardia treatment requirements as specified by regulation, it is necessary to accurately describe these processes in QMRA models. This is of importance to generate risk calculation outputs that accurately estimate the actual risk of infection associated to these protozoan parasites. Moreover, to better understand the parameters that contribute to performance variations of these processes, it is of interest to fill the gaps with regards to the influence of source water quality variations and the impact of filter media surface properties may have on Cryptosporidium and Giardia removal by granular filtration. The general objective of this Ph.D. thesis is to understand the role of (i) media aging and (ii) of the particulate properties of influent water on protozoan parasite removal by granular media filters.
3 citations
Cites background from "Influence of organic carbon loading..."
...L’adsorption de MON à la surface des grains cause une diminution de la rétention d’oocystes en milieu poreux (Metge et al. 2010)....
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...C’est pourquoi la rétention d’oocystes est corrélée à la fraction de la surface des grains couverte d’oxydes de métaux (Abudalo et al. 2005, Metge et al. 2010)....
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Dissertation•
01 May 2011
2 citations
Cites background from "Influence of organic carbon loading..."
...Surfactants have been found to promote transport of oocysts (Metge et al., 2010), viruses (Foppen et al....
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...Surfactants have been found to promote transport of oocysts (Metge et al., 2010), viruses (Foppen et al., 2006, Cao et al., 2010) and bacteria (Brown et al., 2001, Harvey et al., 2010) by masking the heterogeneity occurring in the grains....
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Dissertation•
04 Apr 2012
TL;DR: Puhakka et al. as discussed by the authors studied the effects of river water infiltration on sub-surface microbiology and physico-chemical water characteristics in a pristine aquifer, and found that the water infiltration had a significant impact on the water quality.
Abstract: TAMPERE UNIVERSITY OF TECHNOLOGY Master’s Degree Programme in Environmental and Energy Technology HAGELIN, TITTA: The effects of river water infiltration on sub-surface microbiology and physico-chemical water characteristics in a pristine aquifer Master of Science Thesis, 91 pages April 2012 Major: Environmental Biotechnology Examiners: Professor Jaakko Puhakka, M.Sc. Johanna Ojala
1 citations
Cites background from "Influence of organic carbon loading..."
...(Miettinen et al. 1996; Kolehmainen et al. 2009a; Schütz et al. 2010) Free enzymes are short-lived because they can be rapidly denatured, degraded or inhibited....
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...Differences in NOM quality may have an influence on bacterial activity (Miettinen et al. 1996; Schütz et al. 2010)....
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...Several studies have demonstrated that lower temperatures result in reduced biodegradation and microbial activity in MAR (Miettinen et al. 1996; Massman et al. 2006 Kolehmainen et al. 2009b)....
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...2010) Depolymerisation of polysaccharides, dephosphorylation of organic molecules, and hydrolysis of the peptide bonds in proteins is carried out by glucosidases, phosphatases and aminopeptidases, respectively, which are the most important extracellular enzymes in humic surface waters (Miettinen et al. 1996; Kolehmainen et al. 2009a)....
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...…dephosphorylation of organic molecules, and hydrolysis of the peptide bonds in proteins is carried out by glucosidases, phosphatases and aminopeptidases, respectively, which are the most important extracellular enzymes in humic surface waters (Miettinen et al. 1996; Kolehmainen et al. 2009a)....
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References
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TL;DR: Data indicate that SUVA, determined at 254 nm, is strongly correlated with percent aromaticity as determined by 13C NMR for 13 organic matter isolates obtained from a variety of aquatic environments and is shown to be a useful parameter for estimating the dissolved aromatic carbon content in aquatic systems.
Abstract: Specific UV absorbance (SUVA) is defined as the UV absorbance of a water sample at a given wavelength normalized for dissolved organic carbon (DOC) concentration. Our data indicate that SUVA, determined at 254 nm, is strongly correlated with percent aromaticity as determined by 13C NMR for 13 organic matter isolates obtained from a variety of aquatic environments. SUVA, therefore, is shown to be a useful parameter for estimating the dissolved aromatic carbon content in aquatic systems. Experiments involving the reactivity of DOC with chlorine and tetra- methylammonium hydroxide (TMAH), however, show a wide range of reactivity for samples with similar SUVA values. These results indicate that, while SUVA measurements are good predictors of general chemical characteristics of DOC, they do not provide information about reactivity of DOC derived from different types of source materials. Sample pH, nitrate, and iron were found to influence SUVA measurements.
3,618 citations
"Influence of organic carbon loading..." refers methods in this paper
...Specific UV absorbance (SUVA254) was determined by dividing the UV absorbance measured at 254 nm by the DOC concentration and reported in units of milligrams carbon per liter according to methods outlined in Weishaar et al. (2003)....
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Book•
01 Jan 2007
TL;DR: This book discusses water Microbiology in Public Health, soil, Rhizosphere and Phyllosphere, and the role of aerobiology in these environments.
Abstract: Section I: Introduction to Environmental Microbiology Section II: General Methodology Section III: Water Microbiology in Public Health Section IV: Aquatic Environments Section V: Soil, Rhizosphere and Phyllosphere Section VI: Subsurface and Landfills Section VII: Aerobiology Section VIII: Biotransformation and Biodegradation
1,489 citations
TL;DR: Numerical experiments indicated that increasing the colloid excluded volume of the pore space resulted in earlier breakthrough and higher peak effluent concentrations as a result of higher pore water velocities and lower residence times, respectively.
Abstract: A conceptual model for colloid transport is developed that accounts for colloid attachment, straining, and exclusion. Colloid attachment and detachment is modeled using first-order rate expressions, whereas straining is described using an irreversible first-order straining term that is depth dependent. Exclusion is modeled by adjusting transport parameters for colloid-accessible pore space. Fitting attachment and detachment model parameters to colloid transport data provided a reasonable description of effluent concentration curves, but the spatial distribution of retained colloids at the column inlet was severely underestimated for systems that exhibited significant colloid mass removal. A more physically realistic description of the colloid transport data was obtained by simulating both colloid attachment and straining. Fitted straining coefficients were found to systematically increase with increasing colloid size and decreasing median grain size. A correlation was developed to predict the straining co...
649 citations
TL;DR: In this article, the influence of colloid size and soil grain size distribution characteristics on the transport and fate of the colloid particles in saturated porous media was explored, and the final spatial distribution of retained colloids by the porous media were found to be highly dependent on the colloids size and the soilgrain size distribution.
Abstract: [1] Saturated soil column experiments were conducted to explore the influence of colloid size and soil grain size distribution characteristics on the transport and fate of colloid particles in saturated porous media. Stable monodispersed colloids and porous media that are negatively charged were employed in these studies. Effluent colloid concentration curves and the final spatial distribution of retained colloids by the porous media were found to be highly dependent on the colloid size and soil grain size distribution. Relative peak effluent concentrations decreased and surface mass removal by the soil increased when the colloid size increased and the soil median grain size decreased. These observations were attributed to increased straining of the colloids; i.e., blocked pores act as dead ends for the colloids. When the colloid size is small relative to the soil pore sizes, straining becomes a less significant mechanism of colloid removal and attachment becomes more important. Mathematical modeling of the colloid transport experiments using traditional colloid attachment theory was conducted to highlight differences in colloid attachment and straining behavior and to identify parameter ranges that are applicable for attachment models. Simulated colloid effluent curves using fitted first-order attachment and detachment parameters were able to describe much of the effluent concentration data. The model was, however, less adequate at describing systems which exhibited a gradual approach to the peak effluent concentration and the spatial distribution of colloids when significant mass was retained in the soil. Current colloid xfiltration theory did not adequately predict the fitted first-order attachment coefficients, presumably due to straining in these systems. INDEX TERMS: 1831 Hydrology: Groundwater quality; 1832 Hydrology: Groundwater transport
646 citations
TL;DR: The role of anionic surfactants in the environment is ambiguous: they can cause serous environmental pollution with toxic effect on living organisms; otherwise, they can promote the decomposition and/or removal of other inorganic and organic pollutants from the environment.
492 citations
"Influence of organic carbon loading..." refers background in this paper
...If incomplete degradation of anionic surfactants during waste water treatment (Cserháti et al., 2002; Mungray and Kumar, 2008) occurred, future wastewater discharges into the Russian River would likely increase levels of anthropogenic organic compounds within water being drawn through the…...
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