A ground-water prototype detection system was developed to measure in situ electrical conductivity (EC) of ground water. The system, termed “permanent conductivity points” (PCP), consisted of a number of conductivity cells individually comprised of two-array electrodes attached to a rigid pipe. This system was a “long” conductivity meter permanently installed into the aquifer. It was developed to detect and delineate deicing materials deposited into the ground water of an unconfined sandy roadside aquifer. Measurements from the PCPs provided maximum EC values, which provided a measure of the plume contaminant strength. An extensive site characterization was performed using standard characterizing tools to provide soil, ground water, and the soil/ground-water matrix properties. This information was used to describe the research aquifer, to provide in sight for PCP installation, and to corroborate the PCP measurements. The calibration of the PCPs was performed in the laboratory under carefully controlled conditions providing a reliable calibration factor. Numerous in situ EC measurements were compared to the PCP measurements. The most appropriate comparison was the low-flow ground-water sampling ports (WSP) that were placed directly adjacent to the conductivity cells. Numerous profiles, cross sections, and temporal plots from PCP EC measurements were presented to better describe the delineation of the deicing material in the underlying roadside aquifer. The PCPs were monitored between 1 June 1998 and 19 December 2000 during the research project, encompassing two road-salting seasons. The PCPs proved to be useful in detecting the presence of deicing materials. The maximum contaminant plume EC PCP readings were just over 7500 μS/cm and the ambient were around 70 μS/cm. PCPs were also beneficial in delineating the shape and extent of the contaminant plume. The maximum measured width of the contaminant plume was 60 m and the maximum measured thickness was 10 to 12 m using PCP data. A potential cost savings using PCP technology for long-term ground-water monitoring is possible for geoenvironmental engineering consulting firms when the installation cost, material cost, and personnel sampling-time needed with standard ground-water monitoring wells is considered. The PCP is a low-cost technology that is beneficial for long-term ground-water quality monitoring.

The primary goal of this research was to improve understanding of the fouling of low pressure hollow fiber membranes used in drinking water treatment. The major difference of this study compared to other reported studies was the use of a hollow fiber membrane module at operating conditions mimicking those of full-scale practice. Two poly(vinylidene-fluoroethylene) based hollow fiber membranes (A and B) were tested. Different types of fouling indices (total, hydraulic irreversible, chemical irreversible) developed based on a resistance in series model were used to assess membrane performance. Data from bench-scale and full-scale plants were compared to validate the use of fouling indices. The impact of dissolved organic nitrogen (DON) on membrane fouling was demonstrated with model waters containing humic substances and several model organic nitrogen compounds. Three different natural water sources normalized to the same organic content were tested. Fouling indices determined from the resistance in series model approach were more applicable for natural waters than for model waters. Fouling was proportional to throughput for both raw and pretreated water and at different flux rates. Pretreatment (coagulation) reduced hydraulic irreversible fouling. Most fouling was reversed by hydraulic and chemical cleaning. Specific flux and fouling indices of the bench-scale system were higher than those of the full-scale system but the fouling index ratios were comparable suggesting a similar fouling nature. A minimum of a few days of testing is recommended for longer-term membrane performance assessment. The impact of high DON concentration on membrane fouling was insignificant. Membrane fouling was dependant on foulant properties other than, or in addition to, molecular size and the DON/DOC ratio. With three different natural water sources normalized to a similar organic content, membrane fouling was specific to membrane type and water source. High initial total and hydraulic irreversible fouling rates did not lead to high chemical irreversible fouling rates. It is not possible to generalize the impact of different water sources on membrane fouling. Membrane surface anlyses showed that hydraulically irreversible organic foulants were detected as mostly hydrocarbons/polysaccharides, humic substances and peptide/protein. Humic substances and peptide/protein were found to be organic foulants regardless of their molecular weight and origin. Chemical cleaning with chlorine solution was effective in removing all inorganic foulants and most organic foulants.

An investigation of manganese release from manganese oxide coated filter media, observed in a water treatment plant (WTP), was performed. The study involved collection of the ground water (GW) and the full scale green sand (GS) filter media, 16S rRNA gene sequencing of the extracted DNA from freshly sampled GW and GS, laboratory column experiments with the collected GS and GW followed by 16S rRNA gene sequencing of the DNA from GS used in the laboratory column experiments. In 16S rRNA gene sequencing of the DNA collected from the GW and GS, Geobacteraceae, Burkholderia ferrariae, Galionella feruginea, Ochrobactrum, Mesorhizobium, Pseudomonas and Methylobacrum were found as the most dominant species. Among the sequenced microorganisms, ∼20% for the GW and ∼45% for the GS microorganisms were manganese reducers. In laboratory column experiments, a significant level of manganese release was observed from the column with adequate carbon source and non-autoclaved media. The manganese release continued as long as the carbon source was available and no chlorine was added. 16S rRNA gene sequencing results, performed with the DNA from GS before and after the application pre-filter chlorine, showed a significant decrease in the manganese reducers (40% as compared to 97% for the sodium acetate fed non chlorinated situation). The molecular analysis results are in excellent agreement with the laboratory column experiment observation and strongly suggest that the manganese release can occur in GW treatment plants due to the activity of manganese reducing microorganisms; a high level of solution phase free chlorine can limit the release. Possibe manganese-NOM interaction/complexation in raw, filter influent and filter effluent water samples collected from several WTPs was investigated via the high performance size exclusion chromatography (HPSEC) method with continuous UV detection coupled with an inductively coupled plasma mass spectrometer (ICP-MS). The HPSEC-UV254-ICPMS results showed two major UV 254 peaks and one manganese peak at different HPSEC elution times suggesting no significant NOM-manganese complexation. In laboratory column experiments with full scale filter media, some NOM adsorption was observed for media grains having a larger aluminum to manganese coating ratio, however no correlation could be demonstrated regarding how different molecular size fraction of NOM may impact manganese removal by the oxide coated media.

Total organic halogen (TOX) is an analytically defined measurement that can provide an estimate of total organic bound halogen in water. The analysis of TOX in drinking water indicates that a large amount of the TOX formed during disinfection processes cannot be attributed to known specific disinfection byproducts. There has been a concern over the impact that the unknown fraction of TOX might have on human health. The standard TOX method cannot differentiate organic chlorine, bromine, and iodine. Ion chromatographic (IC) detection has been proposed for the halogen specific TOX analysis. The first objective of this research was to determine the optimum TOX protocol for use with IC detection to analyze total organic chlorine (TOCl), bromine (TOBr), and iodine (TOI). The pyrolytic analyzer using pure O 2 and off-line IC combined with a standard TOX carbon (coconut based) worked best for the differential TOX analysis. The second objective of this research was to assess the impact of bromide and iodide concentrations, different oxidation scenarios, and reaction conditions on the formation of unknown TOX. Chloramines and chlorine dioxide produced byproducts with a higher percentage of unknown TOX than free chlorine. Free chlorine formed more TOCl and TOBr than chloramines and chlorine dioxide in the presence of bromide. However, chloramines and chorine dioxide produced more TOI than chlorine and ozone in the presence of iodide. The third objective was to characterize unknown TOX precursors using resin (XAD-8, XAD-4) extraction and ultrafiltration methodologies. Hydrophobic and high molecular weight natural organic matter (NOM) was found to be a more important precursor for unknown TOX formation than hydrophilic and low molecular weight NOM. The forth objective was to determine the size and hydrophobicity of unknown TOX in drinking water. Total organic halogen from several finished waters was isolated using XAD resins and ultrafiltration membranes. A large fraction of the unknown TOX was comprised of hydrophilic compounds with high molecular weights. Ultrafiltration membranes were found to reject TOX compounds with molecular weights substantially below the membrane cutoffs. Neglecting this effect can lead to overestimation of the molecular size of TOX compounds.

<p> Erosion along shorelines in open water bodies and waterways is a major cause in conversion of wetlands and uplands to an open water environment. Conventional shoreline protective structures are expensive to construct in these environments, and they may impede environmental exchanges that are essential for connectivity and functionality. The Wave Suppression and Sediment Collection (WSSC) System (Wave Robber&trade;) could become an alternative Device in shoreline protection. The primary goals of this study are to evaluate its performance in both wave reductions and sediment collection in the lab, and to optimize the design and to compare the efficiency of the Device in different conditions. This study showed that the WSSC can collect and retain sediment while reducing about 84 to 90% wave height. A new mass balance model was developed to evaluate its performance in sediment collection. A variable &agr;, ranging from 0 to 1, represents the sediment collection efficiency of the Devices, was introduced into this model. The sediment data fitted the model reasonably well, yielding the correlation coefficients of about 0.87. Modeling results show that the sediment collection efficiency of WSSC for silt-clay soil was about 14%. The model used could become useful for not only evaluating this Device, but even using it to evaluate existing Devices. The sensitivity study showed that the wave height and the initial concentration were the most important factors effecting sediment collection. Water depth also plays an important role in that it reduces the sediment collection as the water depth increases. The preliminary field study showed some elevation changes behind the WSSC due to sediment accumulation.</p>

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-11, Section: B, page: 7600. Adviser: Jian Ku Shang. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--Syracuse University, 2008. / "Publication number: AAT 3323068."

<p> The island of Puerto Rico, a commonwealth of the United States of America, has a population of 3,725,789 according to the 2010 census, and generates 11,100 tons daily of waste. In the Island, landfilling is the dominant form of waste disposal. Most municipal solid waste landfills (MSWLF) in Puerto Rico are a principal source of land, water, and air pollution. In addition, the scarcity of appropriate land to open new landfill facilities make this type of waste disposal an unsustainable form of waste management for the Island. </p><p> This study evaluated the current situation of the MSWLFs in Puerto Rico and the geographic limitations of continuing with this type of waste disposal on the Island. As alternatives to this problem, the principal waste-to-energy (WTE) technologies, combustion and gasification, are evaluated as environmentally responsible forms for disposal of non-recycled waste. </p><p> The evaluation methodology used is based on a multi-criteria decision-making model that uses a subjective rank-order weighting method. Evaluation of WTE technologies is performed by comparing dissimilar indicators in five interest areas: technical, economic, environmental, socio-political, and risk. The methodology is composed of two-components: an expert survey and data analysis. </p><p> An evaluation of the environmental interest area was performed to assess which of the WTE technologies studied herein, combustion or gasification, is more environmentally responsible. In addition, using the relevant scores in different interest areas, they were evaluated to determine the economic benefits of these WTE technologies as viable waste management alternatives for Puerto Rico.</p><p>

<p> Urbanization causes increases in impervious cover, alteration of stream channels, and introduction of pollution sources to waterways. Two rain gardens were installed at the headwaters of the Jenkintown Creek to combat urbanization effects and protect the stream from increased stormwater runoff, which can lead to higher flood peaks and pollution control problems. Thermal pollution found in urban runoff is a significant contributor to degradation of streams. Some fish such as the brown trout can be severely affected by heated runoff and many organisms lack the ability to regulate their body temperature. The goal of this research was to assess the thermal impacts from two rain gardens on the headwaters of the Jenkintown Creek from temperature surges during rainfall events. This goal was accomplished by analyzing two and half years of continuous data during non-winter months from a weather station and a flow meter located downstream of the rain gardens. The data from the weather station were precipitation and air temperature. The flow meter data included flow depth, velocity, and temperature. Three months of pre-construction data were collected before the first rain garden was installed. </p><p> The data analysis revealed that surges in water temperature of up to 3.3 &deg;C are found in the headwaters of the Jenkintown Creek almost immediately after it starts raining. A weak correlation (R² = 0.31) between the total water temperature change and studied storm intensity was found. Comparison of pre- and post-construction data showed that the median water temperature surge decreased by approximately 1 &deg;C after the installation of the first rain garden located approximately 315 meters upstream of the flow meter. The installation of the second rain garden located approximately 10 meters upstream of the flow meter did not cause a significant change in temperature surge. The cause of this decrease in temperature can be attributed to the transfer of heat from the hot runoff to the soils in the rain garden. Although a 1 &deg;C decrease of temperature surges is a small number, such a decrease can have a tremendous impact on cold water species such as the brown trout. </p><p> This research is part of the Delaware River Watershed Initiative (DRWI), funded by the William Penn Foundation (WPF).</p><p>

Investigations were conducted at a salt/premix storage facility lying on top of a glacial drumlin near the coastline in eastern Massachusetts, to characterize salt contaminated groundwater. Groundwater hydrogeochemical variations at different depths were determined based on ten years of monthly or quarterly water quality data from 54 monitoring wells. Groundwater was grouped in three water categories – shallow, middle and deep. Hydrogeochemical characterization indicates that the dominant water types are Na-Cl, Na-Ca-Cl and Ca-HCO 3 from the shallow to deep water group. Rock weathering is the dominant hydrogeochemical process for deep water group, whereas salt water percolation and cation exchange control chemical compositions of the shallow and middle water groups. Groundwater is classified as post-cation exchange, under-cation exchange and non-cation exchange groups. Gaseous CO2 and total dissolved inorganic carbon (TDIC) transport in unsaturated and saturated zones of the glacial drumlin was also investigated. A measurement system with non-dispersive infrared gas sensors was used to monitor the recovery of CO2 concentration in the headspace of purged monitoring wells. The transient, radial diffusion of CO2 from surrounding soil to the monitoring well is analogous to an existing slug test theory when the headspace is fully mixed. A nested Fibonacci search was performed to calibrate equilibrium soil CO2 concentration cO and soil gas porosity θS near the water table. The results demonstrate that water table wells with partially submerged screens can facilitate the equilibrium between the gaseous and dissolved phase of CO2. In the saturated zone, a new model was developed to describe the vertical transport of TDIC in the groundwater. The vertical transport was considered to be a balance of uniform vertical advection and vertical dispersion, subject to a first order source term with two boundary conditions at depth and at the water table. Fifteen years of monthly or quarterly data from 28 monitoring wells in the southern part of the site were used to calibrate a vertical dispersivity α of 5.9 cm and a first order source constant λ of 8.2 x10-9 s-1. These values suggest minimal degassing of groundwater CO2 across the water table and till deposition during Late Wisconsinan deglaciation of the region.