Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Download Bioreactor Landfills Promoted By Leachate Recirculation full books in PDF, epub, and Kindle. Read online Bioreactor Landfills Promoted By Leachate Recirculation ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Author : Samuel T. S. Yuen
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (222 download)
Download or read book Bioreactor Landfills Promoted by Leachate Recirculation written by Samuel T. S. Yuen and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Timothy G. Townsend
Publisher : Routledge
ISBN 13 : 1351435892
Total Pages : 202 pages
Book Rating : 4.3/5 (514 download)
Download or read book Landfill Bioreactor Design & Operation written by Timothy G. Townsend and published by Routledge. This book was released on 2018-12-19 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using biotechnology to help control landfill processes can mitigate costs, shorten the time needed to process solid waste, and ease the typical ecological damage to the land being used. This first-of-its-kind book provides regulators, designers, landfill owners, and operators with information that supports the utility of landfill bioreactors and provides design and operating criteria essential for the successful application of this technology. It pulls together laboratory, pilot, and full-scale experiences into one concise guide to designing and running municipal landfills as bioreactors. Landfill Bioreactor Design and Operation covers the history and background of landfill technology, research studies of actual bioreactor landfills, expected leachate and gas yields, specific design criteria, operation guidelines, and reuse of landfill sites to avoid having to establish new sites. For anyone looking for an alternative to large, wasteful landfill sites, this book provides a practical alternative to the problem.
Author :
Publisher :
ISBN 13 :
Total Pages : 128 pages
Book Rating : 4.:/5 (31 download)
Download or read book State of the Practice for Bioreactor Landfills written by and published by . This book was released on 2002 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Aminollah Ghorbanpourbabakandi
Publisher :
ISBN 13 :
Total Pages : 119 pages
Book Rating : 4.:/5 (896 download)
Download or read book Leachate Recirculation Modeling Using Vertical Wells in Bioreactor Landfills written by Aminollah Ghorbanpourbabakandi and published by . This book was released on 2014 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: Municipal solid waste (MSW) is made up of household and commercial waste. Total MSW generated in USA in 2009 was 243 million tons and 54.3% of this waste generation was landfilled (EPA, 2009). MSW buried in landfills contribute a significant amount of gas (Landfill Gas or LFG) to atmosphere. The landfilled MSW is the third largest methane contributor to the atmosphere. One way to manage the LFG is the concept of bioreactor landfills. A bioreactor landfill is a controlled landfill where liquid and gas conditions are actively managed in order to accelerate or enhance biostabilization of MSW. Biostabilization of MSW is usually enhanced by leachate recirculation through MSW. Leachate recirculation can be implemented using different techniques. Using vertical wells, which is the topic of this study, is one way to recirculate leachate in a landfill. Vertical wells are more common in retrofit landfills that implementation of horizontal trenches are not possible or economical. The leachate recirculation system can contain a bunch of single wells, or a bunch of well clusters. In this study, the performance of both single and cluster arrangement was studied. The main objective of this study was to model the leachate recirculation using vertical wells in order to predict the wetted area around the well. HYDRUS-2D was used to create finite element models that simulate the field condition. The area of interest in this study was the Cefe Valenzuela landfill in Corpus Christi, TX. Currently, the landfill is permitted by Texas Commission on Environmental Quality (TCEQ) to operate as Enhanced Leachate Recirculation (ELR) landfill. The preliminary design details of vertical wells have been used in this study. However, an extensive experimental program carried out to characterize the MSW. The experimental program showed the fresh or partially degraded state of MSW. However, in some locations such as 40 ft of BH-1 and BH-2 the MSW is mostly degraded. Based on the laboratory test results two set of material properties, one representing the fresh or partially degraded state and another representing the mostly degraded state, were developed and assigned as MSW properties. Numerical simulations were performed using various leachate quantity and anisotropy factors. Longer lateral extent of leachate distribution is achieved when higher leachate quantity is injected or more anisotropic factor is assumed. Also, the lateral extent was higher in the mostly degraded MSW. In fresh or partially degraded MSW, the affected zone profile is oval shape with the well at top; however, for mostly degraded MSW it is more circular with the well at center. Leachate injection using a well cluster also was simulated to predict the group behavior of vertical wells. Cluster of two wells was found an efficient arrangement that affects a large area; however, cluster of three wells was not efficient because of the short space below the lowest well. Finally, simulations were validated based on the City of Denton Landfill. Simulations were performed for the City of Denton using same approach for this study. The simulation results were matching with the available electrical resistivity images of the recirculated area.
Author : Mazen Mohamad Haydar
Publisher :
ISBN 13 :
Total Pages : 458 pages
Book Rating : 4.3/5 (129 download)
Download or read book Leachate Recirculation in Bioreactor Landfills written by Mazen Mohamad Haydar and published by . This book was released on 2005 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Roberto Valencia Vazquez
Publisher : CRC Press
ISBN 13 : 1439828377
Total Pages : 159 pages
Book Rating : 4.4/5 (398 download)
Download or read book Enhanced stabilisation of municipal solid waste in bioreactor landfills written by Roberto Valencia Vazquez and published by CRC Press. This book was released on 2008-12-01 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: Municipal solid waste entombed in landfills will produce pollution in the form of landfill gas and leachate when the barriers fail in the long term. Bioreactor landfills are an alternative solution to avoid such negative impacts and to achieve a more stable residue, the so-called Final Storage Quality (FSQ) of residues. However, until now the main
Author : Ricardo Coelho De Abreu
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (54 download)
Download or read book Facultative Bioreactor Landfill written by Ricardo Coelho De Abreu and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A relatively new concept of Municipal Solid Waste treatment is known as bioreactor landfill technology. Bioreactor landfills are sanitary landfills that use microbiological processes purposefully to transform and stabilize the biodegradable organic waste constituents in a shorter period of time. One of the most popular types of bioreactor landfills is the landfill with leachate recirculation. However, it is observed that ammonia rapidly accumulates in landfills that recirculate leachate and may be the component that limits the potential to discharge excess leachate to the environment. In the facultative landfill, leachate is nitrified biologically using an on-site treatment plant and converted by denitrifying bacteria to nitrogen gas, a harmless end-product. In this research, three pilot-plant scale lysimeters are used in a comparative evaluation of the effect of recirculating treated and untreated leachate on waste stabilization rates. The three lysimeters are filled with waste prepared with identical composition. One is being operated as a facultative bioreactor landfill with external leachate pre-treatment prior to recirculation, the second is being operated as an anaerobic bioreactor landfill with straight raw leachate recirculation, and the third one is the control unit and operated as a conventional landfill. Apart from environmental restrictions, geotechnical constraints are also imposed on new sanitary landfills. The scarcity of new potential disposal areas imposes higher and higher landfills, in order to utilize the maximum capacity of those areas. In this context, the knowledge of the compressibility of waste landfills represents a powerful tool to search for alternatives for optimization of disposal areas and new solid waste disposal technologies. This dissertation deals with and discusses the environmental and geotechnical aspects of municipal solid waste landfills. In the Environmental Engineering area, it compares the quality of the leachate and gas generated in the three lysimeters and discusses the transfer of the technology studied through lysimeters to procedures for full-scale operation. In the geotechnical area, this dissertation discusses the compressibility properties of the waste and provides a state-of-the-art review of MSW compressibility studies. It also evaluates the compressibility of MSW landfills for immediate and long-term settlements and proposes a new model for compressibility of waste landfills.
Download or read book Slope Stability of Bioreactor Landfills During Leachate Injection: Effects of Heterogeneous and Anisotropic Municipal Solid Waste Conditions written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In bioreactor landfills, leachate recirculation can significantly affect the stability of landfill slope due to generation and distribution of excessive pore fluid pressures near side slope. The current design and operation of leachate recirculation systems do not consider the effects of heterogeneous and anisotropic nature of municipal solid waste (MSW) and the increased pore gas pressures in landfilled waste caused due to leachate recirculation on the physical stability of landfill slope. In this study, a numerical two-phase flow model (landfill leachate and gas as immiscible phases) was used to investigate the effects of heterogeneous and anisotropic nature of MSW on moisture distribution and pore-water and capillary pressures and their resulting impacts on the stability of a simplified bioreactor landfill during leachate recirculation using horizontal trench system. The unsaturated hydraulic properties of MSW were considered based on the van Genuchten model. The strength reduction technique was used for slope stability analyses as it takes into account of the transient and spatially varying pore-water and gas pressures. It was concluded that heterogeneous and anisotropic MSW with varied unit weight and saturated hydraulic conductivity significantly influenced the moisture distribution and generation and distribution of pore fluid pressures in landfill and considerably reduced the stability of bioreactor landfill slope. It is recommended that heterogeneous and anisotropic MSW must be considered as it provides a more reliable approach for the design and leachate operations in bioreactor landfills.
Author : Mohamed E. S. M. Abdallah
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (13 download)
Download or read book A Novel Computational Approach for the Management of Bioreactor Landfills written by Mohamed E. S. M. Abdallah and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Rainer Stegmann
Publisher :
ISBN 13 : 9788862650021
Total Pages : 348 pages
Book Rating : 4.6/5 (5 download)
Download or read book Landfill aeration written by Rainer Stegmann and published by . This book was released on 2007 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Md Zahangir Alam
Publisher :
ISBN 13 :
Total Pages : 185 pages
Book Rating : 4.:/5 (987 download)
Download or read book Moisture Distribution Efficiency and Performance Evaluations of Bioreactor Landfill Operations written by Md Zahangir Alam and published by . This book was released on 2017 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioreactor landfills are operated in a modern engineered way to accelerate waste decomposition, gas production, and waste stabilization. The major aspect of a bioreactor landfill operation is associated with the addition of supplemental liquid or leachate recirculation, and the effective operation primarily depends on efficient moisture distribution throughout the waste mass, which enhances performance. The performance of an effective landfill operation can be assessed by several indicators, i.e., leachate generation, gas production, and landfill settlement. Bioreactor landfill operations have several significant economic and environmental advantages, but the impact of efficient moisture distribution and the assessment of performance through combined indicators is not well established. Hence, explaining and quantifying such impact on performance monitoring is essential to understanding an effective operation. The overall objective of this research was to monitor moisture distribution, due to leachate recirculation, throughout the landfill and to evaluate the performance of landfill operations. Leachate recirculation was performed through horizontal recirculation pipes and vertical injection wells. The City of Denton Landfill, in Denton, Texas, USA was selected as the site for the field investigations. A field program was conducted, using the electrical resistivity imaging (ERI) technique to determine moisture variations with time (one day, one week, two weeks) due to leachate recirculation through the horizontal and vertical recirculation systems. The data of field performance indicators, i.e., leachate generation, gas production, and landfill settlement, was collected from the landfill authority and analyzed to observe the bioreactor performance. Field leachate generation was compared with the Visual HELP model results to correlate it with the gas generation. The combined effect of indicators was analyzed to evaluate landfill performance. The research provides data on the significant factors of successful bioreactor landfill operations: the application frequency of leachate, and moisture distribution efficiency due to leachate recirculation through vertical injection wells. The research develops an understanding the effect of indicators and the assessment of landfill performance through evaluating the essence of individuals and combined indicators. Scheduling the leachate recirculation is one of the most vital actions required for distributing the moisture in the underlying waste. A comprehensive understanding of moisture variations in a bioreactor landfill, by reason of circulating leachate, is important for determining the frequency of leachate recirculation. The estimated moisture content for the baseline study was 31.5% before the next cycle of leachate recirculation to the adjacent recirculation pipe. However, the moisture content after 1 day, 7 days and 14 days after leachate recirculation was found 49.52%, 40.48%, and 31.74%, respectively. Several recirculation systems are currently being used at different locations across the world; however, vertical injection wells are the specific objects of interest in leachate recirculation due to their potential advantages over other available systems. Based on the results of the studies pertaining to vertical wells, the initial moisture content ranged from 31.5% to 36.5% before liquid was added through the vertical wells. The moisture content observed rose from 49.5% to 64.6% within one day after the leachate injection; however, it decreased one week after leachate injection, ranging from 40.12% to 47.03%. Two weeks after leachate injection, the moisture content ranged from 31.75% to 38.6%. The performance of bioreactor landfills can be monitored by several indicators, i.e., moisture distribution, leachate generation, gas production, water balance, and landfill settlement. Combining the different parameters to assess the performance of a bioreactor landfill has not been widely investigated. The results from the water balance simulation model, Visual HELP, show that the actual leachate generation in the field is approximately 55% lower than the HELP model results. The reason that the leachate return from the landfill is lower might be that the added water/leachate is being partially used for gas production. Hence, an increase in gas generation was observed, increasing from 543.6 m3/h (320 scfm) in 2010-2011 to 1087.3 m3/h (640 scfm) in 2014-2015. Moreover, in some locations of the landfill cells, from 2014 to 2015, an approximate total of 1.45 m (4.8 ft.) of maximum settlement was found in the landfill.
Author : Shahed R. Manzur
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (858 download)
Download or read book Hydraulic Performance Evaluation of Different Recirculation Systems for ELR/bioreactor Landfills written by Shahed R. Manzur and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The major aspect of bioreactor landfill is the addition of liquid and recirculation of collected leachate back into the waste mass through the subsurface Leachate Recirculation System (LRS). The leachate recirculation system consists of the perforated recirculation pipes placed inside horizontal trenches and the permeable beds with different orientation. The application of high permeability material (shredded tire chips, broken glass, pea gravel) in landfills is an emerging technology to distribute the moisture over a wider area in a shorter period of time. Horizontal or vertical perforated pipes are installed in bioreactor landfills as LRS with an expectation of uniform moisture distribution within waste to optimize the performance of bioreactor landfill. However, high heterogeneity, variability and anisotropy of MSW and the different compaction energy used in landfill may dominate the flow pattern inside the waste mass that may result variable moisture level inside landfills. In addition, moisture has a tendency to follow the preferential channels to reach the leachate collection system that even complicates to attain a uniform moisture distribution throughout the landfill. Therefore, attaining uniform moisture level for microbial activity becomes a challenge in bioreactor landfill operation. A series of Resistivity Imaging tests (RI) were performed to investigate the performance of recirculation pipes placed (1) directly on waste, (2) inside a trench with shredded tire bedding and (3) on top of permeable blankets at the City of Denton landfill. The experimental results indicated that the resistivity of the solid waste decreased with the addition of water/leachate through the horizontal trench. It was also observed from the RI test results that leachate flow along pipe is non-uniform throughout the pipe. The non-uniformity of leachate flow confirms that the flow of leachate through waste is mostly through preferential flow paths due the heterogeneous nature of the waste. The RI profiles from the baseline, recirculation and monitoring results at east, middle and west test sections indicate that resistivity decreases immediately after addition of water/ leachateHowever, the resistivity increases upto its original level after two weeks of recirculation at all locations. Therefore, based on the initial decrease and subsequent rebound of resistivity, the frequency of recirculation may be recommended bi-weekly basis to maintain a threshold moisture level inside the waste pack. It was also observed that moisture distribution is better when the recirculation pipe is placed on horizontal trench with tire chip as bedding materials. For the performance of permeable bed (tire chip bedding), temperature sensors were installed at middle and two sides of waste pack. Based on the resistivity and temperature variation results, it was observed that moisture was not traveling all the way to the sides of the waste pack and was flowing down only through the middle of the permeable tire chip materials. The subsidence results during the monitoring period indicate the subsidence of the waste mass to be around 2 ft to 3 ft. More settlement was observed at locations where more water or leachate was added. Therefore, higher settlement was observed near H2, compared to H16, H22, and H26. This directly co-relates to the percentage decrease in resistivity due to moisture or leachate addition.
Author : Kiran Kumar Penmethsa
Publisher :
ISBN 13 : 9781109815283
Total Pages : 104 pages
Book Rating : 4.8/5 (152 download)
Download or read book Permeability of Municipal Solid Waste in Bioreactor Landfill with Degradation written by Kiran Kumar Penmethsa and published by . This book was released on 2007 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Permeability is an important parameter during the design of leachate collection and recirculation system. In the current study an experimental program was designed to determine the variation of coefficient of permeability of MSW with degradation and to determine the influence of density and cover soil on permeability of MSW.
Author : Timothy J. Murphy
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (645 download)
Download or read book A Comparative Evaluation of Liquid Infiltration Methods for Bioreactor Landfills written by Timothy J. Murphy and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Instead of merely disposing of municipal solid waste (i.e., MSW, garbage, refuse) in a traditional landfill, new technology is being developed to treat landfilled waste in situ by designing and operating the landfill as a biological treatment system or bioreactor. Increasing the moisture content of solid waste to 40% or more (by leachate recirculation or water addition) enhances the biodegradation process. However the probable existence of preferential flow paths prevents wetting the entire waste mass to biologically optimal conditions. Significant areas of concern include the operational aspects of applying leachate to waste in the landfill. In leachate recirculation projects found in the literature, a variety of infiltration methods were used to introduce leachate back to the landfill mass. However, a direct comparison of the effectiveness of the methods was not found. Therefore, this research evaluated four methods of wetting MSW and assessed the effectiveness of each method. This project included the design and dissemination of a questionnaire to determine the current state of practice in bioreactor technology in the U.S. and a laboratory study of four liquid infiltration methods. The infiltration methods were: trickle irrigation cascade system; horizontal trench; single wells; and cluster wells. The project used four 2.0 m3 laboratory-scale landfills containing "engineered" MSW. Evaluation of moisture distribution was performed using two different types of in-situ moisture sensors and a dye tracer study to determine distribution of moisture and flow rates. Results of the project indicated that; three liquid infiltration methods were utilized by respondents to the bioreactor questionnaire, a larger number of respondents to the bioreactor questionnaire are needed to determine if design parameters are emerging from industry and academia. The GMX in-situ moisture monitoring instruments did not sense moisture content below 40%, to reliably sense moisture content both the TDT and GMX sensors must be in intimate contact with the surrounding media. The cluster well method provided the greatest overall increase in the moisture content of the waste during the experiments. However, none of the infiltration methods tested wetted the waste to the desired 40% moisture content during the 8 hour test runs.
Author : State University College (Oswego, N.Y.). Environmental Research Center
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (388 download)
Download or read book Leachate Recirculation at the Nanticoke Sanitary Landfill Using a Bioreactor Trench written by State University College (Oswego, N.Y.). Environmental Research Center and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Mohamed Adil Haque
Publisher : ProQuest
ISBN 13 : 9780549138136
Total Pages : pages
Book Rating : 4.1/5 (381 download)
Download or read book Dynamic Characteristics and Stability Analysis of Municipal Solid Waste in Bioreactor Landfills written by Mohamed Adil Haque and published by ProQuest. This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioreactor landfills are operated to enhance refuse decomposition, gas production, and waste stabilization. The major aspect of bioreactor landfill operation is the recirculation of generated leachate back through the refuse mass. Due to the accelerated decomposition and settlement of solid waste, bioreactor landfills are gaining popularity as an alternative to the conventional landfill designed under Subtitle D regulations. However, recirculation of leachate or addition of water to accelerate the waste decomposition changes the biodegradation and geotechnical characteristics of waste mass. Our understanding of changes in engineering characteristics of solid waste with accelerated decomposition is limited. There is a need to understand and explain the changes in characteristics associated with stability analysis of landfills. The objective of this research is to study the changes in strength characteristics of municipal solid waste (MSW) in bioreactor landfills with time and decomposition. In order to understand the changes in strength properties of MSW in bioreactor landfills with time and decomposition an experimental program was developed. Eight small scale reactors, representative of bioreactor landfill, were built in laboratory, and samples were prepared to represent different phases of decomposition. The state of decomposition was quantified by methane yield, pH, and volatile solids. The geotechnical testing program (CD triaxial test and resonant column tests) was performed to determine shear strength and dynamic characteristics of MSW in bioreactor landfill. The test results indicated that the measured shear strength and dynamic properties of MSW are significantly affected by the degree of decomposition. The friction angle of MSW decreased from 26.7° in Phase I to 19° in Phase IV. The shear modulus increased from 2.11 MPa in Phase I to 12.56 MPa in Phase IV. The change in shear strength and dynamic properties of MSW was attributed to the breakdown in fibrous nature of solid waste particles with degradation. Based on the measured experimental results, stability analyses were conducted. The finite element program PLAXIS and limit equilibrium program STABL was used to analyze the stability of MSW in bioreactor landfills. The stability was evaluated at both under normal and those during earthquake conditions. The factor of safety estimated using PLAXIS and GSTABL under both the conditions decreased as the solid waste degraded with time. The results indicates that the stability of bioreactor landfills should be evaluated using the strength characteristics determined as a function of time and decomposition rather than using average values.
Author : Jennifer Ann Loudon
Publisher :
ISBN 13 :
Total Pages : 102 pages
Book Rating : 4.:/5 (773 download)
Download or read book Reductive Dehalogenation Potential in a Leachate Recirculating Bioreactor Landfill and Its Affect on Leachate Toxicity written by Jennifer Ann Loudon and published by . This book was released on 2011 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Halogenated organic compounds may enter landfills through emplacement of various types of waste and are often detected in leachate. While leachate is a complex mixture of both organic and inorganic contaminants, the overall toxicity may be influenced by the presence of halogenated organic compounds. Leachate recirculating bioreactor landfills are generally anaerobic and support a diverse microbial community. The major hypothesis of this study was that leachate recirculating bioreactor landfill microorganisms can biotransform halogenated organic compounds and thus increase or decrease the toxicity of landfill leachate. To test the hypothesis, anaerobic microcosms were developed using elutriated landfill solids or leachate solids collected from the Burlington County Resource Recovery Center (BCRRC) leachate recirculating bioreactor landfill. The microcosms were amended with tetrachloroethene (PCE) as a model halogenated compound. In the landfill solids microcosms PCE dechlorination to cis-1,2-dichloroethene was observed, and in the leachate solids microcosms PCE dechlorination to ethene was observed, indicating the presence of dechlorinating microorganisms in the landfill system. The bacterial communities present in the raw landfill materials and the microcosms were compared using polymerase chain reaction amplification of 16S rRNA genes followed by denaturing gradient gel electrophoresis. There were distinct phylogenic differences between the communities, and phylotypes of the known dehalogenating bacterial genus, Dehalobacter, were detected in transfer enrichments of the leachate and solids microcosms. A Zebrafish embryo larval assay (ELA) was used to evaluate the toxicity of landfill leachate. One hundred percent mortality occurred when the embryos were exposed to solutions containing 16% leachate by volume over an exposure period of 24 hours. Various sublethal lesions were observed at lower concentrations. ELAs performed on microcosm supernatant yielded similar results. Minimal change in supernatant toxicity occurred as a result of incubating the material under conditions enhancing reductive dechlorination in the microcosms. Fractionation of the leachate suggested that most of the lethal toxicity could be attributed to the inorganic/metal fraction of the landfill leachate as opposed to the fraction containing the organic contaminants. Our results suggested that dehalogenating microorganisms are present in the BCRRC leachate recirculating bioreactor landfill and that landfill leachate toxicity can be assessed using the Zebrafish ELA approach.
