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Polychlorinated Biphenyl Dechlorination With Palladized Magnesium - Development Of A Sediment Remediation Technology, Emese Hadnagy

Doctoral Dissertations

PCB contamination in sediments remains a significant problem in many rivers, harbors, and estuarine areas in the US and around the world. In this work, PCB dechlorination by palladium-coated magnesium (Mg/Pd, 0.01% by weight Pd) has been demonstrated in PCB-contaminated marine and freshwater sediments from New Bedford Harbor (NBH), MA; and the Housatonic River (HSR), MA. Experiments were also conducted in pure solvent systems (10% methanol in distilled water). In addition, the performance of an in-situ sediment remediation system capable of delivering and mixing chemical amendments into sub-aqueous sediments and at the same time providing enclosed conditions was evaluated by …

Evaluation Of Reactive Cap Sorbents For In-Situ Remediation Of Contaminated Sediments, Bhawana Sharma

Doctoral Dissertations

Contaminated sediments can be treated using in-situ treatment methods that aim to either degrade or sequester contaminants, reducing their bioavailability. The main purpose of this research was to develop and evaluate a reactive capping mat that can be used for in-situ remediation of contaminated sediments. This study investigated the interferences caused by humic acid on the adsorption of co-planar and non-co-planar polychlorinated biphenyls (PCBs) including 2-chlorobiphenyl, 2, 2', 5, 5'-tetrachlorobiphenyl, 3, 3', 4, 4'-tetrachlorobiphenyl, 2, 2', 4, 4', 5, 5'-hexachlorobiphenyl and 3, 3', 4, 4', 5, 5'-hexachlorobiphenyl and polycyclic aromatic hydrocarbons (PAHs) including naphthalene, phenanthrene and pyrene on two types …

Geochemical Weathering Of Granular Byproduct Materials, Robert K. Carter

Master's Theses and Capstones

Granular byproducts of artificial systems, such as municipal solid waste incinerator ash (MSWI) and coal combustion, are limited in re-use applications because of concern for their long-term environmental behavior with particular focus on the release of heavy metals. Understanding the solid phases within these materials and their influence on heavy metal leaching is necessary for development of an approach to potential re-use applications. Application of traditional geomorphologic principles may describe the solid phases of man-made systems and their development over time. This research addresses identification of the solid phases by use of Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy …

Economic And Environmental Considerations For Construction And Demolition (C&D) Debris Management And Policy, Andria Vachon

Master's Theses and Capstones

Construction and demolition (C&D) debris is a significant part of the waste stream in the United States. Recycling is increasingly becoming a more popular method of disposal due to both market and regulatory forces; however, most of the debris is still landfilled. C&D debris facilities handle materials with low value and have few market opportunities. Limited recycling opportunities may be available for hazardous materials. A survey of mixed material C&D recyclers in the United States is analyzed in this paper. Some topics of interest covered in the survey included: end uses and markets for recycled materials; technological processes utilized by …

Protistan Predation And Tce Biodegradation In A Fractured Rock Aquifer, Joseph J. Cunningham Iii.

Master's Theses and Capstones

Despite extensive research on the resources required to initiate dechlorination of trichloroethene (TCE), slow rates and stalling continue to be observed in situ. The majority of research on biodegradation of TCE has focused resource availability, while predation is poorly understood. Predation has the potential to significantly alter bacterial abundance, and can play an important role in selecting what species are present, and determine if the community is capable of mineralizing TCE. The impact of protistan predation on TCE biodegradation rates, and occurrence and length of stalls was measured in this experiment. When protists were inhibited, TCE was mineralized. Protistan predation …

Winter Performance Assessment Of Permeable Pavements: A Comparative Study Of Porous Asphalt, Pervious Concrete, And Conventional Asphalt In A Northern Climate, Kristopher M. Houle

Master's Theses and Capstones

This study presents the findings from two active parking lots constructed of permeable pavements: porous asphalt and pervious concrete. Focus is given to the performance of these pavements in a cold-climate setting. Winter places great demands on pavements so it is of particular interest to evaluate how they compare to conventional designs. Analyses include measurements of frost penetration, surface infiltration rates, snow and ice cover, skid resistance, chloride retention, and effective salt loads. Infiltration rates were retained in winter conditions and with frost depths as high as 27-inches. A 75% average reduction in annual salt use was observed for porous …

Removing Radium-226 Contamination From Ion Exchange Resins Used In Drinking Water Treatment, James F. Mcmahon Iii.

Master's Theses and Capstones

Many groundwater sources used for drinking water in the United States contain naturally occurring gross alpha emitting radium-226 that exceeds the National Drinking Water Standards maximum contaminant level. The health risks associated with continuous and intermittent exposure to these low levels of naturally occurring radioactive material (NORM) over long periods of time can cause genetic damage which may lead to effects such as cancer. The EPA identifies ion exchange resins as a best available technology (BAT) in radium-226 removals. This determination has resulted in an increased need for knowledge about the characteristics of these resins. The ability of the resins …

An Investigation Of Recycled/Industrial Materials To Attenuate Hydrogen Sulfide Resulting From The Use Of Construction And Demolition Debris Fines, Kelly Ann Melendez Loaiza

Master's Theses and Capstones

One of the products of Construction and Demolition (C&D) debris recycling is C&D debris fines. C&D debris fines closely resemble soil. They may contain metal scraps, gypsum drywall, wood, soil, shingles, and concrete. Landfills have utilized C&D debris fines as alternative daily cover and/or shaping and grading material. The use of C&D debris fines has been linked to diffuse hydrogen sulfide emissions at landfills. Hydrogen sulfide emissions are not only a nuisance, but may pose a health hazard to landfill workers. This research investigates how recycled materials may be used to attenuate hydrogen sulfide emissions resulting from the use of …

Measuring Suspended Sediment Characteristics To Identify Accurate Monitoring Techniques In Stormwater Runoff, George Deforest Fowler

Master's Theses and Capstones

This research examined several methods for monitoring suspended sediment concentration and particle size in stormwater runoff.

Suspended sediment concentration was monitored using the following methods: automatic sampling reported as Suspended Sediment Concentration (SSC), automatic sampling reported as Total Suspended Solids (TSS), turbidity reported as SSC and turbidity reported as TSS. Particle size distribution (PSD) was measured in samples from automatic samplers using tri-laser diffraction. An entire volume of the discharge passing by the automatic samplers and turbidity meter was captured and presumably contained the actual values to which all other methodologies were compared.

Automatic sampling with SSC proved to be …