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Full-Text Articles in Environmental Engineering

Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, Simon Kozik May 2024

Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, Simon Kozik

All Graduate Theses and Dissertations, Fall 2023 to Present

Per and poly-fluorinated alkyl substances (PFAS) are a class of chemicals that are persistent in the environment. PFAS was found in wastewater, which can be used after wastewater treatment for irrigation water, and in the biosolids that can be mixed with soils to provide nutrients and generally improve soil quality. This study found when wastewater was used it increases the level of PFAS in vegetables and forage grass. PFAS concentrations were tracked from the influent of the wastewater treatment plant to the effluent, to the irrigation water, to the soil, and finally into the vegetable and forage grass grown on …


A Review Of Harmful Algal Bloom Prediction Models For Lakes And Reservoirs, Jade Snyder Echard May 2021

A Review Of Harmful Algal Bloom Prediction Models For Lakes And Reservoirs, Jade Snyder Echard

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Anthropogenic activity has led to eutrophication in water bodies across the world. This eutrophication promotes blooms, cyanobacteria being among the most notorious bloom organisms. Cyanobacterial blooms (more commonly referred to as harmful algal blooms (HABs)) can devastate an ecosystem. Cyanobacteria are resilient microorganisms that have adapted to survive under a variety of conditions, often outcompeting other phytoplankton. Some species of cyanobacteria produce toxins that ward off predators. These toxins can negatively affect the health of the aquatic life, but also can impact animals and humans that drink or come in contact with these noxious waters. Although cyanotoxin’s effects on humans …


Application Of Flow And Ion Data To Estimate Ungaged Inflows And Losses In Urban And Agricultural Sub-Reaches Of The Logan River Observatory, Hyrum Tennant May 2021

Application Of Flow And Ion Data To Estimate Ungaged Inflows And Losses In Urban And Agricultural Sub-Reaches Of The Logan River Observatory, Hyrum Tennant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Streams in urban and agricultural environments are often heavily diverted for irrigation and drinking water purposes. These streams can receive inflow from unmeasured sources including stormwater returns, groundwater drains, and irrigation runoff that will help sustain flow during dry periods. Due to an inability to identify the source of most of these inflows or directly measure their volumes, there is a clear need for identification and quantification methods. Streamflow data from the Logan River Observatory illustrates the importance of unidentified inflows in sections influenced by large diversions. To understand the role of unidentified inflows and possible outflows in this portion …


Trisiloxane Surfactant Adjuvants In Pollen, Autumn Slade Aug 2020

Trisiloxane Surfactant Adjuvants In Pollen, Autumn Slade

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chemicals are often added to agricultural pesticide mixes to help increase the efficiency of the field spray solution, and one of the main groups of chemicals used for this purpose are trisiloxane surfactants (TSSs). Normally TSSs are considered non-toxic, but recent studies have shown TSSs to have negative impacts on organisms like honey bees. Though TSSs have recently been found in environmental sources like water, pollen, and beeswax, little is known about how TSSs behave in the environment or affects active ingredients, like pesticides.

To help determine the environmental prevalence and fate of TSSs, several studies were performed. Pollen was …


Application Of Winslamm To Evaluate The Effect Of Green Infrastructure Implementation In Northern Utah, Rosa A. Fernández Velásquez Dec 2018

Application Of Winslamm To Evaluate The Effect Of Green Infrastructure Implementation In Northern Utah, Rosa A. Fernández Velásquez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study provides an evaluation of the performance of the WinSLAMM model in two cities of northern Utah, a region in which it has not been validated to date. Runoff volumes for a series of events from 2015 to 2017 were calculated for six study areas. These results were compared to model outputs to evaluate the prediction accuracy. The model performed poorly when default parameters where used, as expected. Thus, the calibration of runoff coefficient was done with local data. Total suspended solids (TSS), total phosphorus (TP) and total dissolved phosphorus (TDP) were also evaluated and calibrations were developed. The …


Utah Salt Storage Facilities Guidelines And Best Management Practices, Weston Bellon May 2018

Utah Salt Storage Facilities Guidelines And Best Management Practices, Weston Bellon

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

An environmental analysis was conducted at the Utah Water Research Laboratory of samples gathered from Utah Department of Transportation (UDOT) salt storage facilities retention ponds across the state. The analysis indicated high levels of TSS largely made up of minerals directly associated with the deicing solution currently used by UDOT in roadway applications. As a companion to that analysis, best management practices have been identified and compiled to provide a resource for the proper management of salt storage facilities in the state of Utah. Topics included as best management practices include locating new storage facilities, proper salt storage, proper salt …


Evaluation Of A Side-By-Side Full-Scale Biofiltration Conversion In A Nutrient-Limited Environment, Stetson S. Bassett May 2018

Evaluation Of A Side-By-Side Full-Scale Biofiltration Conversion In A Nutrient-Limited Environment, Stetson S. Bassett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to meet increasing water demands and more stringent regulations drinking water treatment plant managers must continually look to new treatment strategies and optimization techniques. One such strategy is to eliminate chlorine residual before filtration, allowing indigenous bacteria already present in the source water to grow on the filter media. These microorganisms help improve effluent water quality by increasing organic and inorganic contaminant removal. The process is known as biological filtration, or biofiltration. The implications of converting a conventional filtration plant (not specifically designed for biofiltration) to a biofiltration plant are still not well understood. Therefore, the purpose of …


Ph Effects On The Sorption Of Fluoxetine And Sulfamethoxazole By Three Powdered Activated Carbons, James D. Schneider May 2018

Ph Effects On The Sorption Of Fluoxetine And Sulfamethoxazole By Three Powdered Activated Carbons, James D. Schneider

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pharmaceuticals and personal care products (PPCPs) are widely used throughout the world. PPCPs are emerging as pollutants of concern and may pose a risk in the future to drinking water supplies. Two such compounds are sulfamethoxazole (SMXL) and fluoxetine (FLX). These ionizable compounds are not readily removed from water by conventional water treatment technologies. Powdered activated carbon (PAC) is a useful material for removing contaminants from water and is currently used in many water treatment applications. PACs may carry either a net positive or negative surface charge depending on the pH of solution. This study examined the hypothesis that the …


Desorption Of Trace Inorganic Contaminants From Solids In Drinking Water Distribution Systems, Tiana W. Hammer May 2018

Desorption Of Trace Inorganic Contaminants From Solids In Drinking Water Distribution Systems, Tiana W. Hammer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to maintain high quality safe drinking water, we need to understand what happens after the water has been cleaned at the drinking water plant and before it gets to the consumer’s house. Even if low concentrations of toxic contaminants enter the drinking water distribution system (DWDS) there is potential for contaminants to accumulate and be released by changes in flow or water conditions in high concentrations at the tap. For this study, we collected solid material from Park City, Utah that accumulated within the DWDS, along with a year of monthly monitoring of the DWDS. These solids were …


Pharmaceuticals And Personal Care Products In An Effluent-Dominated Stream: Seasonal Variability And Downstream Fate, Bradley R. Buswell May 2017

Pharmaceuticals And Personal Care Products In An Effluent-Dominated Stream: Seasonal Variability And Downstream Fate, Bradley R. Buswell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pharmaceuticals and personal care products (PPCPs) consist of a large group of compounds including medicines, lotions, soaps, shampoos, and even flame retardants and insect repellants. After use, PPCPs often enter waste streams that are directed to municipal wastewater treatment plants (WWTPs). Due to inefficient removals in conventional wastewater treatment processes, WWTP discharges into streams and rivers are a major source of PPCPs to the environment.

The East Canyon Water Reclamation Facility (ECWRF) is a WWTP in Park City, Utah. After treatment, the ECWRF effluent is discharged into a small constructed wetland area before it enters East Canyon Creek. Due to …


Quantifying The Removal Of Trichloroethylene Via Phytoremediation At Hill Air Force Base, Utah Operational Unit 2 Using Recent And Historical Data, J. Oliver Diamond May 2016

Quantifying The Removal Of Trichloroethylene Via Phytoremediation At Hill Air Force Base, Utah Operational Unit 2 Using Recent And Historical Data, J. Oliver Diamond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Trichloroethylene (TCE) is a carcinogenic, chlorinated volatile organic compound that was commonly used as a degreasing solvent for aircraft maintenance at many US Air Force bases. Past improper disposal of TCE has resulted in contaminated groundwater plumes surrounding many of these facilities. Phytoremediation, defined as the use of plants and their associated microorganisms to stabilize or remove contamination, has been implemented as part of a TCE groundwater cleanup effort at Travis Air Force base near Sacramento, CA and is being considered as a remediation option at other bases. Volatilization of TCE from leaves and the surface of the soil near …


Anaerobic Digestion Process Stability And The Extension Of The Adm1 For Municipal Sludge Co-Digested With Bakery Waste, Morris Elya Demitry May 2016

Anaerobic Digestion Process Stability And The Extension Of The Adm1 For Municipal Sludge Co-Digested With Bakery Waste, Morris Elya Demitry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The anaerobic digestion process is used to treat and convert waste organic matter to biogas (principally methane and carbon dioxide) through biological, chemical and physical reactions. The biogas can be used as a source of energy recovery. In order to increase the biogas production rate, two different kinds of waste (municipal wastewater treatment sludge and bakery waste) were mixed together to enhance the anaerobic process and increase the biogas production in pilot scale reactors. The process succeeded in increasing biogas production and at the same time kept the process of treatment effective when high rates of organics were fed to …


Catalytic Pyrolysis Of Olive Mill Wastewater Sludge, Hamza Abdellaoui May 2015

Catalytic Pyrolysis Of Olive Mill Wastewater Sludge, Hamza Abdellaoui

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

From 2008 to 2013, an average of 2,821.4 kilotons/year of olive oil were produced around the world. The waste product of the olive mill industry consists of solid residue (pomace) and wastewater (OMW). Annually, around 30 million m3 of OMW are produced in the Mediterranean area, 700,000 m3 year−1 in Tunisia alone. OMW is an aqueous effluent characterized by an offensive smell and high organic matter content, including high molecular weight phenolic compounds and long-chain fatty acids. These compounds are highly toxic to micro-organisms and plants, which makes the OMW a serious threat to the environment if …


Stormwater Bioretention: Nitrogen, Phosphorous And Metal Removal By Plants, Malgorzata Rycewicz-Borecki May 2015

Stormwater Bioretention: Nitrogen, Phosphorous And Metal Removal By Plants, Malgorzata Rycewicz-Borecki

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stormwater runoff is an environmental concern. It increases the volume and velocity of surface water flow and contains high pollutant concentrations. High flows erode stream channels. Nutrients in the runoff cause eutrophication. Some metals from stormwater runoff is regulated by the Federal National Pollution Discharge Elimination System (NPDES). Bioretention (BR) systems are often used in response to these regulations to retain and treat this stormwater runoff.

This study conducted greenhouse and field experiments, and evaluated differences in nutrient and metal removal among plant species that are typically found growing in BR systems but are not typically investigated in this detail. …


Evaluation Of Composting Of Municipal Solid Waste, J. Ryan Stebbins May 2014

Evaluation Of Composting Of Municipal Solid Waste, J. Ryan Stebbins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Millions of tons of organic waste are lost each year by being deposited in landfills instead of being composted. Composting would increase the life of landfills and reduce the loss of renewable resources. Current composting techniques take approximately 6 months to break down the organic components, such as yard trimmings and food waste. In addition, a large amount of area is required for the windrows piles. Recycling techniques help to separate organics, such as yard trimmings and food waste, from the municipal solid waste (MSW) stream for composting. However, these techniques are time consuming, costly, and not extensively practiced. Since …


Effect Of Deposition From Static Test Fires On Corn And Alfalfa, Scout Mendenhall May 2013

Effect Of Deposition From Static Test Fires On Corn And Alfalfa, Scout Mendenhall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alliant Techsystems, Inc (ATK) manufactures solid rocket motors for the National Aeronautics and Space Administration (NASA) at the Promontory, UT facility. Periodically ATK conducts static test fires, where the rocket is restrained horizontally and fired into a hillside. The plume entrains native soil and is carried by the wind until it cools and settles. Although the area around ATK is sparsely populated, residents of nearby Penrose and Thatcher, UT are concerned with the deposition of the test fire soil (TFS) from the static rocket tests. In 2010, several crop fields nearing harvest were dusted with TFS, prompting the investigation of …


Using Qual2kw As A Decision Support Tool: Considerations For Data Collection, Calibration, And Numeric Nutrient Criteria, Andrew J. Hobson May 2013

Using Qual2kw As A Decision Support Tool: Considerations For Data Collection, Calibration, And Numeric Nutrient Criteria, Andrew J. Hobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface water quality in the United States is managed by the U.S. Environmental Protection Agency (EPA) under direction of the Clean Water Act. Designated uses are required for all state waters. Numeric or narrative water quality standards provide measures to determine if each waterbody meets the intended use. Narrative standards typically include vague terminology that is difficult to interpret and this has led EPA to encourage states to develop numeric criteria for nutrients in all its streams, rivers, and lakes. These numeric nutrient criteria are intended to stave off the harmful effects of over-growth of aquatic plants which can result …


Assessing Phosphorus-Transport From Biosolids Land Application Sites In Utah, Mohan K. Kumar May 2011

Assessing Phosphorus-Transport From Biosolids Land Application Sites In Utah, Mohan K. Kumar

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Phosphorus Site Index (PSI) is a phosphorus transport assessment tool used to estimate the risk of P transport from soils. Various components, such as soil erosion, P fertilizer application rate, plant available P in soil, etc. that have an influence on P transport from a site, are weighted and given ratings, and a combination of these components are expressed as PSI. This study has considered two biosolids land application sites in Utah, which received biosolids amendments over time, to develop a specialized PSI for the state of Utah.

Phosphorus from land application of biosolids has been considered a potential risk …


Measuring The Removal Of Trichloroethylene From Phytoremediation Sites At Travis And Fairchild Air Force Bases, Heather A. Klein May 2011

Measuring The Removal Of Trichloroethylene From Phytoremediation Sites At Travis And Fairchild Air Force Bases, Heather A. Klein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Past use of trichloroethylene (TCE) as a degreasing solvent for aircraft maintenance has resulted in widespread groundwater contamination at Air Force Bases around the world. Travis AFB in California and Fairchild AFB in Washington are evaluating phytoremediation as a treatment option, since trees have been reported to take up dissolved TCE from shallow groundwater and volatilize it to the atmosphere while enhancing the volatilization of TCE from surrounding soil. Previous studies generally focused on the identification of removal mechanisms. The emphasis of this research was to quantify total TCE removal from phytoremediation demonstration plots at Travis and Fairchild AFBs.

Tree …


Variability Of Water Storage And Instream Temperature In Beaded Arctic Streams, Madeline F. Merck May 2011

Variability Of Water Storage And Instream Temperature In Beaded Arctic Streams, Madeline F. Merck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to investigate variation in water export and instream temperatures throughout the open water season in a beaded Arctic stream, consisting of small pools connected by shallow chutes. The goals are to better understand heat and mass movement through these systems, how this may impact chemical and biological processes, and the resulting shifts with changes in climate. This is accomplished by first examining the extent and variability of water storage and export through qualitative analysis of observational data. Further, heat fate and transport is examined through development of an instream temperature model. The model formulation, …


Sustainable Management Of Duckweed Biomass Grown For Nutrient Control In Municipal Wastewaters, Maureen Kesaano May 2011

Sustainable Management Of Duckweed Biomass Grown For Nutrient Control In Municipal Wastewaters, Maureen Kesaano

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of duckweed as a nutrient removal option for municipal wastewaters can only be realized through regular plant harvesting. As a result, the nutrient-rich biomass generated needs to be effectively managed and disposed of. This study looked at three alternative options for biomass management that would make duckweed-based nutrient removal systems sustainable and attractive to small communities like Wellsville City, Utah. The options included: the use of harvested duckweed biomass as an animal feed, anaerobic digestion of duckweed for methane production, and fermentation of biomass for ethanol production.

Duckweed feed quality was determined using feed analysis reports and results …


Retrieval Of Aerosol Mass Concentration From Elastic Lidar Data, Christian C. Marchant Dec 2010

Retrieval Of Aerosol Mass Concentration From Elastic Lidar Data, Christian C. Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural aerosol sources can contribute significantly to air pollution in many regions of the country. Characterization of the aerosol emissions of agricultural operations is required to establish a scientific basis for crafting regulations concerning agricultural aerosols. A new lidar instrument for measuring aerosol emissions is described, as well as two new algorithms for converting lidar measurements into aerosol concentration data. The average daily aerosol emission rate is estimated from a dairy using lidar.

The Aglite Lidar is a portable scanning lidar for mapping the concentration of particulate matter from agricultural and other sources. The instrument is described and performance and …


Fundamentals Of Operation Of The Induced Bed Reactor (Ibr) Anaerobic Digester, Jacob Shaun Dustin May 2010

Fundamentals Of Operation Of The Induced Bed Reactor (Ibr) Anaerobic Digester, Jacob Shaun Dustin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Induced Bed Reactor (IBR) was developed at Utah State University to apply high-rate anaerobic digestion techniques to high solids content substrates. This technology has been successfully implemented at full-scale multiple installations in the United States and Canada as a waste treatment and energy production technology, but the physical processes necessary to further optimize the system were not well understood.

Bench scale IBRs were operated as anaerobic digesters at 35°, 45°, and 55° C under three organic loading rates and three corresponding hydraulic retention times. Reactor performance was monitored at steady state for residence time distribution and substrate reduction.

The …


Remotely Sensed Data Assimilation Technique To Develop Machine Learning Models For Use In Water Management, Bushra Zaman May 2010

Remotely Sensed Data Assimilation Technique To Develop Machine Learning Models For Use In Water Management, Bushra Zaman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increasing population and water conflicts are making water management one of the most important issues of the present world. It has become absolutely necessary to find ways to manage water more efficiently. Technological advancement has introduced various techniques for data acquisition and analysis, and these tools can be used to address some of the critical issues that challenge water resource management.

This research used learning machine techniques and information acquired through remote sensing, to solve problems related to soil moisture estimation and crop identification on large spatial scales. In this dissertation, solutions were proposed in three problem areas that can …


Data Collection And Analysis Methods For Two-Zone Temperature And Solute Model Parameter Estimation And Corroboration, Quinten Glen Bingham May 2010

Data Collection And Analysis Methods For Two-Zone Temperature And Solute Model Parameter Estimation And Corroboration, Quinten Glen Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water temperature directly affects biological and chemical processes of fresh water ecosystems. Elevated instream temperatures are commonplace in the Virgin River of southwestern Utah during summer due to a hot desert climate and high water demands that result in low stream flows. This is of concern since the Virgin River is home to two endangered species, the Virgin River Chub (Gila seminuda) and Woundfin (Plagopterus argentissimus). Efforts to model instream temperatures within the Virgin River have been undertaken to help mitigate elevated instream temperatures including the development of a two-zone temperature and solute (TZTS) model. This …


Comparison Of Agricultural Area Source Ammonia Gas Concentration And Flux Measurements, Emyrei Reese May 2010

Comparison Of Agricultural Area Source Ammonia Gas Concentration And Flux Measurements, Emyrei Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted in order to compare and evaluate a variety of ammonia (NH3) measurement techniques for determination of ambient gas phase concentration and evaluation of system fluxes. This was accomplished by measuring NH3 emitted from area sources within two dairies, one located in south-central Idaho and another in central California. The measurement techniques utilized included: an array of passive diffusion samplers, a single annular denuder system, a single or paired Fourier transform infrared spectrometer(s) (FTIR), a paired (upwind and downwind) set of differential optical absorption spectrometers (DOAS), and a portable wind tunnel in conjunction with a …


Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin May 2010

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …


Quantifying Surface Water And Groundwater Interactions In A High-Gradient Mountain Stream For Solute Transport, Noah M. Schmadel Dec 2009

Quantifying Surface Water And Groundwater Interactions In A High-Gradient Mountain Stream For Solute Transport, Noah M. Schmadel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study reach in a mountain stream highly influenced by groundwater was selected to test common data collection strategies used to characterize and quantify groundwater exchange processes necessary to predict solute transport. The data types collected include: high frequency discharge estimates with the use of rating curves, dilution gauging techniques with instantaneous tracer experiments, groundwater table and stream water surface elevations, vertical head gradients, and hydraulic conductivity estimates. The first two data types were categorized as stream gauging and the remaining three data types as site characterization. The stream gauging data were used to quantify net changes in stream discharge …


Removal And Utilization Of Wastewater Nutrients For Algae Biomass And Biofuels, Erick W. Griffiths Dec 2009

Removal And Utilization Of Wastewater Nutrients For Algae Biomass And Biofuels, Erick W. Griffiths

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Logan City Environmental Department operates a facility that consists of 460 acres of fairly shallow lagoons (~ 5'deep) for biological wastewater treatment that meets targets for primary and secondary treatments (solids, biological oxygen demand (BOD), and pathogen removal). Significant natural algal growth occurs in these lagoons, which improves BOD removal through oxygenation and also facilitates N removal through volatilization as ammonia under high pH conditions created by algal growth. Phosphorus, however, is non-volatile and stays in the water and likely cycles in and out of algal cells as they grow and die in the lagoons. In the near future, …


Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa Dec 2008

Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Operable Unit 5 (OU 5) area of Hill Air Force Base currently has two trichloroethene-contaminated groundwater plumes underneath residential areas in Sunset and Clinton, Utah. Bioremediation by biological reductive dechlorination can be an important mechanism for the removal of chlorinated compounds from the plumes. The presence of suitable bacteria to carry on reductive dechlorination is the key in the bioremediation process. The goal of this study was to determine the distribution and population density of the 16S rRNA genes of Bacteria, Dehalococcoides ethenogenes, Desulfuromonas michiganensis, Geobacter spp and Rhodoferax ferrireducens-like bacteria, as well as the functional genes trichloroethene reductive …