Download or read book Compatibility of Geosynthetic Clay Liners GCLs with Multi species Inorganic Solutions written by Dale Christian Kolstad and published by . This book was released on 2000 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compatibility of Geosynthetic Clay Liners with Acidic Solutions written by Yang Liu and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Geosynthetic clay liners (GCLs) are widely used as hydraulic barriers because of their sealing capacity in contact with water. However, with the increasing interest in their use in mining applications, the compatibility issues of GCLs to mining leachates are of some concern. This research work has been undertaken to enhance our understanding of compatibility of GCLs with strong acidic leachates, as for example, which may occur in mining leachates. Three types of bentonites were selected for this research program. Tests included index tests such as Atterberg limits, swell index, fluid loss and suspension rheology under various concentrations of sulfuric acid solutions. The results indicate that all index parameters degraded when the materials were exposed to acidic solutions. The degradation of these indices would indicate a high probability for the degradation of hydraulic performance of GCLs to occur based on established correlations between hydraulic conductivity and these indices. The mineralogical analyses on bentonite components of GCLs before and after reaction with sulfuric acid solutions were conducted using X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. The dissolution of bentonite, loss of water from smectite interlayers, and the collapse of smectite layers were observed using these methods, these observations explained in part the degradation of the engineering indices and hydraulic performance of bentonites or GCLs. A series of flexible-wall permeameter tests were conducted to directly evaluate the hydraulic performance of GCLs when subjected to different concentrations of sulfuric acid solutions. Effective stress and prehydration condition, both of which can affect the hydraulic performance, were also considered. The hydraulic conductivity was observed to increase with increasing sulfuric acid concentration, but specimens prehydrated with water had lower resulting hydraulic conductivity to sulfuric acid leachates than non-prehydrated specimens. Higher applied effective stress tended to decrease the hydraulic conductivity presumably by compressing the specimens thereby resulting in smaller hydraulically active pores. Three powdered polymers, having either negative, positive or neutral charges, were used in this study to determine whether the hydraulic performance of bentonites under acidic conditions could be improved. Any improvements achieved were only observed under deionized water and low sulfuric acid concentration (≤0.015 M). Generally, no significant differences in test parameters caused by the polymer types (cationic, non-ionic and anionic) were observed under DI water and low sulfuric acid concentration (≤ 0.015 M). However, at higher acid concentrations, these polymers tended to lose effectiveness due probably to pH induced changes in polymer conformation, from presumably elongation to aggregate, at the clay surface. Sulfuric acid is detrimental to the hydraulic performance of GCLs, even if GCLs are prehydrated with good quality water. With better knowledge of how GCLs behave under strong acidic conditions, the geotechnical engineering community will be better equipped to approach and resolve potential problems involving interaction between GCLs and acidic solutions.
Download or read book Assessment of the Performance of Engineered Waste Containment Barriers written by National Research Council and published by National Academies Press. This book was released on 2007-08-22 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: President Carter's 1980 declaration of a state of emergency at Love Canal, New York, recognized that residents' health had been affected by nearby chemical waste sites. The Resource Conservation and Recovery Act, enacted in 1976, ushered in a new era of waste management disposal designed to protect the public from harm. It required that modern waste containment systems use "engineered" barriers designed to isolate hazardous and toxic wastes and prevent them from seeping into the environment. These containment systems are now employed at thousands of waste sites around the United States, and their effectiveness must be continually monitored. Assessment of the Performance of Engineered Waste Containment Barriers assesses the performance of waste containment barriers to date. Existing data suggest that waste containment systems with liners and covers, when constructed and maintained in accordance with current regulations, are performing well thus far. However, they have not been in existence long enough to assess long-term (postclosure) performance, which may extend for hundreds of years. The book makes recommendations on how to improve future assessments and increase confidence in predictions of barrier system performance which will be of interest to policy makers, environmental interest groups, industrial waste producers, and industrial waste management industry.
Download or read book Advances in Geosynthetic Clay Liner Technology written by Robert E. Mackey and published by ASTM International. This book was released on 2004 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soon after the inception of ASTM D35.04 Subcommittee on Geosynthetic Clay Liners, the first symposium on Testing and Acceptance Criteria for Geosynthetic Clay Liners (GCLs), STP 1308, was held on 29 January 1996, in Atlanta, Georgia. The intention of the symposium was to bring together the current knowledge and understanding regarding this relatively new product used in containment systems. Since that symposium, numerous GCL standards have been developed along with a greater appreciation of the product's capabilities and limitations. ASTM D35 determined it was time to assess the current state of GCL technology to better address possible revisions of the present ASTM GCL standards and determine what new standards will be required in the future.
Download or read book Cation Exchange and Long term Hydraulic Conductivity of Geosynthetic Clay Liners GCLs Permeated with Inorganic Salt Solutions written by Ho Young Jo and published by . This book was released on 2003 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering written by The Organizing Committee of the 16th ICSMGE and published by IOS Press. This book was released on 2005-09-12 with total page 3742 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 16th ICSMGE responds to the needs of the engineering and construction community, promoting dialog and exchange between academia and practice in various aspects of soil mechanics and geotechnical engineering. This is reflected in the central theme of the conference 'Geotechnology in Harmony with the Global Environment'. The proceedings of the conference are of great interest for geo-engineers and researchers in soil mechanics and geotechnical engineering. Volume 1 contains 5 plenary session lectures, the Terzaghi Oration, Heritage Lecture, and 3 papers presented in the major project session. Volumes 2, 3, and 4 contain papers with the following topics: Soil mechanics in general; Infrastructure and mobility; Environmental issues of geotechnical engineering; Enhancing natural disaster reduction systems; Professional practice and education. Volume 5 contains the report of practitioner/academic forum, 20 general reports, a summary of the sessions and workshops held during the conference.
Download or read book Evaluation of the Long Term Effect of Inorganic Leachate on Geosynthetic Clay Liners written by Darwish El-Hajji and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Because of its low permeability and high swelling characteristics, bentonite is used in various hydraulic barrier systems and in the manufacturing of Geosynthetic Clay Liners (GCLs). Exposure to inorganic solutions containing elevated concentrations of electrolyte can significantly increase their permeability. To enhance the bentonite's chemical resistance to inorganic solutions, the manufacturers of GCL materials introduced propriety soluble polymeric compounds as an additive to bentonite. The resulting materials are referred to as polymer-treated, chemically-enhanced, or contaminant-resistant clays, and are arguably resistant to a host of inorganic chemicals. In this study, the response of both regular and polymer treated bentonite clays to ordinary tap water and inorganic landfill leachate is evaluated using permeability tests, index tests and x-ray diffraction. The results indicate the high dependence of performance on sample preparation techniques, pre-hydration conditions, and first wetting liquid and, to a lesser extent, polymer treatment. The x-ray diffraction results indicate that the samples reached chemical equilibrium during the permeation process, as demonstrated by a full shift in d-spacing from Na-bentonite to Ca-bentonite. Further, the results show that the cation exchange capacity, the clay plasticity ratio, and the swell index appear to be reliable indicators of the hydraulic compatibility of bentonite permeated with inorganic chemicals.
Download or read book Sustainable Environmental Geotechnics written by Krishna R. Reddy and published by Springer Nature. This book was released on 2020-09-07 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains selects papers presented during the Second International Conference on Environmental Geotechnology, Recycled Waste Materials and Sustainable Engineering, held in the University of Illinois at Chicago. It covers the recent innovations, trends, and concerns, practical challenges encountered, and the solutions adopted in geoenvironmental engineering, waste management, and sustainable engineering. This book will be useful for academics, educators, policy makers and professionals working in the field of civil engineering, chemical engineering, environmental sciences and public policy.
Download or read book Effect of Cation Exchange and Desiccation on the Hydraulic Conductivity of GCLS Used in Landfill Covers Laboratory and Field Studies written by Stephen Robert Meer and published by . This book was released on 2003 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Indian Geotechnical Conference 2019 written by Satyajit Patel and published by Springer Nature. This book was released on 2021-06-04 with total page 779 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises select proceedings of the annual conference of the Indian Geotechnical Society. The conference brings together research and case histories on various aspects of geotechnical and geoenvironmental engineering. The book presents papers on geotechnical applications and case histories, covering topics such as (i) Characterization of Geomaterials and Physical Modelling; (ii) Foundations and Deep Excavations; (iii) Soil Stabilization and Ground Improvement; (iv) Geoenvironmental Engineering and Waste Material Utilization; (v) Soil Dynamics and Earthquake Geotechnical Engineering; (vi) Earth Retaining Structures, Dams and Embankments; (vii) Slope Stability and Landslides; (viii) Transportation Geotechnics; (ix) Geosynthetics Applications; (x) Computational, Analytical and Numerical Modelling; (xi) Rock Engineering, Tunnelling and Underground Constructions; (xii) Forensic Geotechnical Engineering and Case Studies; and (xiii) Others Topics: Behaviour of Unsaturated Soils, Offshore and Marine Geotechnics, Remote Sensing and GIS, Field Investigations, Instrumentation and Monitoring, Retrofitting of Geotechnical Structures, Reliability in Geotechnical Engineering, Geotechnical Education, Codes and Standards, and other relevant topics. The contents of this book are of interest to researchers and practicing engineers alike.
Download or read book Geo Congress 2014 Technical Papers written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compatibility of Geosynthetic Clay Liners with Leachate from CCP Management Facilities written by and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments were conducted to evaluate whether coal combustion product (CCP) leachates adversely affect the hydraulic conductivity (K) of geosynthetic clay liners (GCLs) as an alternative material in lieu of a compacted clay liner (CCL). Chemical properties of CCP leachates were compiled based on a nationwide survey of CCP disposal facilities. Five synthetic leachates were developed to represent a range of conditions encountered in CCP disposal facilities: typical CCP leachate, strongly divalent cation fly ash leachate, flue gas desulfurization (FGD) residual leachate, high ionic strength ash leachate, and trona ash leachate. Nine GCLs were tested: two Na-bentonite (NaB) GCLs, six bentonite-polymer (P-B) GCLs, and one bentonite polymer composite (BPC). Hydraulic conductivity tests on GCLs were conducted on prehydrated (60-d on subgrade soil or DI water) and non-prehydrated GCL specimens. Tests were run to hydraulic and chemical equilibrium at effective stresses of 20 kPa, and then higher effective stresses were applied up to 450 kPa. At 20 kPa, the GCLs with NaB had high hydraulic conductivity to CCP leachates (10-10 to 10-6 m/s). Hydraulic conductivity was directly proportional to the ionic strength of the leachate and inversely proportional to the swell index of the bentonite when hydrated in leachates. The hydraulic conductivity of B-P GCLs with low polymer loading (d"1.2%) behaved similarly to NaB GCLs. However, the hydraulic conductivity of GCLs with polymer loading e"1.9 % is controlled by the clogging behavior of polymer hydrogel. Polymer elution was observed during the hydraulic conductivity tests, and increasing hydraulic conductivity was associated with cumulative polymer elution. Increasing the effective stress from 20 to 450 kPa caused the hydraulic conductivity to decrease by up to three orders of magnitude. At 450 kPa effective stress, the hydraulic conductivities of all tests were lower than 10-9 m/s except for one test with Trona leachate. This observation indicates that high effective stress can minimize the effect of CCP chemistry on the hydraulic behavior of GCLs. Subgrade hydration had no beneficial effect on hydraulic conductivity; however, prehydration with DI water can effectively protect the GCLs due to a large amount of immobile water retained in the bentonite
Download or read book Assessment of the Performance of Engineered Waste Containment Barriers written by National Research Council and published by National Academies Press. This book was released on 2007-09-22 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: President Carter's 1980 declaration of a state of emergency at Love Canal, New York, recognized that residents' health had been affected by nearby chemical waste sites. The Resource Conservation and Recovery Act, enacted in 1976, ushered in a new era of waste management disposal designed to protect the public from harm. It required that modern waste containment systems use "engineered" barriers designed to isolate hazardous and toxic wastes and prevent them from seeping into the environment. These containment systems are now employed at thousands of waste sites around the United States, and their effectiveness must be continually monitored. Assessment of the Performance of Engineered Waste Containment Barriers assesses the performance of waste containment barriers to date. Existing data suggest that waste containment systems with liners and covers, when constructed and maintained in accordance with current regulations, are performing well thus far. However, they have not been in existence long enough to assess long-term (postclosure) performance, which may extend for hundreds of years. The book makes recommendations on how to improve future assessments and increase confidence in predictions of barrier system performance which will be of interest to policy makers, environmental interest groups, industrial waste producers, and industrial waste management industry.
Download or read book Long term Hydraulic Performance of Geosynthetic Clay Liners Subjected to Inorganic Salt Solutions written by Jae-Myung Lee and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inorganic Sorption in Polymer Modified Bentonite Clays written by Melody Schwartz Nocon and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: In 1986, geosynthetic clay liners (GCLs) were invented and successfully used as a replacement for the soil layer in composite lining systems. In some applications an additive (polymer) is mixed with the bentonite to increase performance, especially in those that have low concentrations of sodium bentonite (EPA 2001). Studies showing significant increases in hydraulic conductivity values for bentonite in the presence of high salt concentrations are frequently documented and there is a risk of early breakthrough due to performance failure of the GCL clay component. (Ashmawy et al, 2002). It has also been stated that sodium, potassium, calcium, and magnesium have such a high affinity for the clay's surface other chemical species have little chance of attenuation (EPA 2001). For these reasons, researching sorption in the presence of major salt cations and polymers gains great importance. Distribution coefficients were extrapolated from Linear, Freundlich and Langmuir sorption isotherms for sodium and calcium cations modeled from data collected from batch tests of sodium bentonite and various manufactured and custom mixed polymer modified bentonites. Surface characterization before and after calcium or sodium solution exposure of all tested media was accomplished by use of scanning electron microscopy and energy dispersive x-ray analysis.
Download or read book Transportation Water and Environmental Geotechnics written by C. N. V. Satyanarayana Reddy and published by Springer Nature. This book was released on 2021-08-02 with total page 457 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises select proceedings of the Indian Geotechnical Conference 2020 (IGC2020) focusing on emerging opportunities and challenges in the field of transportation geotechnics, scour and erosion, offshore geotechnics, and environmental geotechnology. The contents will be useful to researchers, educators, practitioners and policy makers alike.
Download or read book Geotechnical Practice for Waste Disposal written by D.E. Daniel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earth scientists and geotechnical engineers are increasingly challenged to solve environmental problems related to waste disposal facilities and cleanup of contaminated sites. The effort has given rise to a new discipline of specialists in the field of environmental geotechnology. To be effective, environmental geotechnologists must not only be armed with the traditional knowledge of fields such as geology and civil engineering, but also be knowledgeable of principles of hydrogeology, chemistry, and biological processes. In addition, the environmental geotechnologist must be completely up to date on the often complex cadre of local and national regulations, must comprehend the often complex legal issues and sometimes mind-boggling financial impli cations of a project, and must be able to communicate effectively with a host of other technical specialists, regulatory officials, attorneys, local land owners, journalists, and others. The field of environmental geo technology will no doubt continue to offer unique challenges. The purpose of this book is to summarize the current state of practice in the field of environmental geotechnology. Part One covers broadly applicable principles such as hydrogeology, geochemistry, and con taminant transport in soil and rock. Part Two describes in detail the underlying principles for design and construction of new waste disposal facilities. Part Three covers techniques for site remediation. Finally, Part Four addresses the methodologies for monitoring. The topics of 'waste disposal' and 'site remediation' are extra ordinarily broad.
