OPPORTUNITIES FOR THE USE OF GEOSYNTHETICS IN WASTE MANAGEMENT FACILITIES By Bob Landreth U.S. Environmental Protection Agency Cincinnati, OH SECOND INTERNATIONAL HIGH-PERFORMANCE FABRICS CONFERENCE Sponsored By The Industrial Fabrics Association International November 12-13,1992 The Lenox Hotel Boston, Massachusetts U.S.A. ------- Opportunities for Use of Geosynthetics in Waste Management Facilities Robert E. Landreth U.S. Environmental Protection Agency Risk Reduction Engineering Laboratory Cincinnati, Ohio 45268 ABSTRACT The U.S. Environmental Protection Agency throjjgh its research and field experiences has developed control strategies for hazardous and municipal solid waste landfills and surface impoundments. These control strategies include liner and cover systems. The liner systems include double liners for hazardous waste and a single composite liner for municipal solid waste. The purpose of each individual component will be discussed with options for using natural in-situ materials or geosynthetics. Although natural soils are used as various components, emphasis has been placed on the use of geosynthetics, including geomembranes, geonets, geotextiles, and plastic pipes. Cover systems for both hazardous and municipal waste facilities are based on a multilayer design. The multilayer component characteristics, including performance, thickness and material type will be discussed. These designs include both natural soils and geosynthetics. It has been demonstrated with field data that the development of construction quality control/quality assurance will improve the performance of the disposal facility. The improved performance of the waste management facility reinforces the confidence of designers as they understand the limits of designing with geosynthetics. Information on design and construction has been assembled into technical resource and guidance documents. The documents present summaries of state-of-the-art technologies and evaluation techniques determined by the Agency to constitute good engineering designs, practices, and procedures. The availability of the documents will also be discussed. INTRODUCTION Waste is generated at all levels of society. This waste may be either industry related or municipally generated. Both types of wastes may contain a variety of potential pollutants. In the United States of America these wastes are managed by landfills, surface impoundments and waste piles. The U.S. Environmental Protection Agency through its research and field experiences have developed control strategies to prevent potential pollutants from escaping into the environment. The control strategies for waste management facilities include liner and cover systems. These systems are designed for long-term performance. In addition, for those containment systems for hazardous and toxic wastes, redundancy is designed into the containment systems to help ensure against major releases to the environment. ------- Field experience has clearly demonstrated that the development of construction quality control and quality assurance programs will improve the waste management facility performance. This paper will present current designs for bottom and top containment systems, ideas and concepts for quality control/quality assurance programs and available technical guidance documents to support the designs and programs. BOTTOM CONTAINMENT DESIGNS The basic bottom liner design, for hazardous waste landfills, is two or more liners with a leachate collection system above and between the li'ners. The redundancy aspect of the design is that if the top liner does not perform as designed, then the second leachate collection system will alert appropriate personnel while corrective actions are implemented. The bottom liner in this design is assumed to contain the waste until the corrective action is in place. The design was reviewed and modeled in saturated and unsaturated hydraulic flow conditions. The result of these studies is the current recommended design of a double liner which has a bottom composite liner and a top geomembrane, Figure 1. The composite bottom liner is one that consists of a geomembrane in intimate contact with a compacted, low permeability natural soil. The composite liner design has been determined to-be more hydraulically efficient than the geomembrane or natural soil liner working independently. LinerSystems for Hazardous Hastes The liner system currently being used by most hazardous waste management facilities incorporate in descending order a filter layer, followed by a primary leachate collection and removal system (LCRS), a primary geomembrane, a leak detection, collection and removal system (LCDRS), and a composite liner above the native soil foundation (EPA, 1987). The composite liner is defined as a geomembrane and a compacted, low hydraulic conductivity (k < IxlO"7 cm/sec) natural soil. In bottom liner systems for construction and field seaming purposes, the geomembrane is to be at least 6.75 mm (30 mils) thick or 1.12 mm (45 mils) thick if left exposed to the elements for more than 30 days. These thicknesses may not be suitable for all geomembrane materials. The required geomembrane thickness will depend on the site-specific design, installation/construction concerns, seamability, and long-term durability. Ljmer. Systems for Municjpal Solid Wastes Liner systems for municipal solid wastes may have different designs based on site specific considerations including geology, hydrology and climatic conditions. Two basic approaches are used in the United States. The first is a generic design. This design has a composite liner system that is designed and constructed to maintain less than 30-cm (12-in) depth of leachate over the liner. The second approach based on performance consists of liners and leachate collection systems to ensure that the concentration values of selected chemicals will not be exceeded at some point on the owner/operator's property. ------- optional soil protectivs cover filter layer (soil or geosynthetic} permeability soil r primary liner (geomembrane) secondary liner (composite geomembrans & soi Isachata collection and removal system (soil or gecsynthetic) leak detection, collection and removal system (soil or geosynthetic) Figure 1. Schematic of Double Liner System. optional soil protective cover filter layer (soil or geosynthetic) liner (composite geomembrane & soil) leachate collection and removal system (soil or geosynthetic) Figure 2. Generic Liner Design for Nonhazardous Waste Facility. 155 ------- Generic Design: A composite liner is shown schematically in Figure 2 and is defined as consisting of two components; the upper component is a geomembrane with a minimum of 0.75 mm (30 mil) thickness, the lower component consists of at least a 60 cm (24 inches) layer of compacted soil with a hydraulic conductivity less than or equal to a 1 x 10"7 cm/sec. The required geomembrane thickness will depend upon the site-specific design, installation/construction concerns, seamability and long-term durability. The geomembrane must be installed in direct and uniform contact with the compacted soil component so as to minimize the migration of leachate through potential defects in the geomembrane. A leachate collection and removal system (LCRS) should be located immediately above the composite liner to control the level of leachate on the liner. t Performance Based Design: The second design allows the owner operator of the proposed municipal solid waste landfill (MSWLF) to demonstrate that the design is protective of human health and the environment with respect to ground water quality downgradient from the landfill. The nature of the demonstration is essentially an assessment of the landfill leachate characteristics, the potential for leakage from the landfill of that leachate to ground water and an assessment of the anticipated fate and transport of those constituents to the proposed point of compliance at the facility. Inherent to this type of approach, is the need to obtain sufficient site specific data to adequately characterize the existing ground water quality, the pre-existing ground water regime (flow direction, horizontal and vertical gradients, hydraulic conductivity, specific yield and aquifer thickness). The assessment should consider the effects that construction of the MSWLF may have on the groundwater system. The major consideration here, for shallow groundwater systems, is the local capturing of precipitation that normally would have infiltrated as a source of groundwater recharge. An assessment of leakage from the proposed liner and leachate collection design should be based on empirical data from other existing operational facilities of similar design that have the capability of leak detection monitoring. In lieu of the existence or availability of such information, analytical approaches based on conservative assumptions may need to be conducted to estimate anticipated leakage rates. Given known source concentrations, groundwater and soil parameters, and the hydraulic gradients, a simple and hopefully conservative assessment of downgradient concentration at specific times and distances from the source can be conducted. Either one dimensional or two dimensional advection/dispersion contaminant transport methods may be used. The analysis should be performed by qualified professionals and may entail hypothetical computer simulations of groundwater flow and transport. TOP COVER SYSTEM DESIGNS Proper closure is essential to complete a landfill. Research has established minimum requirements needed to meet the stringent, necessary, closure criteria for both hazardous and nonhazardous waste landfills in the United States. In designing the landfill cover, the objective is to limit the infiltration of water to the waste so as to limit creation of leachate that might possibly escape to groundwater sources. The cover system must be devised at the time the site is selected and the plan and design of the landfill containment structure is chosen. The location, the availability of low-hydraulic conductivity soil, the stockpiling of good topsoil, ------- the availability and use of geosynthetics to improve performance of the cover system, the height restrictions to provide stable slopes, and the use of the site after the postclosure care period are typical considerations. The goals of the cover system are to minimize further maintenance and to protect human health and the environment. Cover System for Hazardous Wastes The closure of a hazardous waste landfill will normally have as its main criteria the minimization of moisture into the facility. Allowing moisture into a hazardous waste facility will subject the waste to leaching of potentially toxic pollutants into the leachate. Minimizing leachates in a closed waste management unit requires that liquids be kept out and that the leachate that does exist be detected, collected, and removed. Where the waste is above the ground-water zone, a properly designed and maintained cover can prevent (for practical purposes) water from entering the landfill and, thus, minimize the formation of leachate. The current recommended design, Figure 3, is a multilayered system consisting of, from bottom to top: A Low-Hydraulic Conductivity Geomembrane/Soil Layer. A 60-cm (24- in.) layer of compacted natural or amended soil with a hydraulic conductivity of 1 x 10"7 cm/sec in intimate contact with a minimum 0.5 mm (20-mil) geomembrane liner. A Drainage Layer. A minimum 30-cm (12-in.) soil layer having a minimum hydraulic conductivity of 1 x 10"2 cm/sec, or a layer of geosynthetic material having the same hydraulic characteristics. A Top. Vegetation/Soil Layer. A top layer with vegetation (or an armored top surface) and a minimum of 60 cm (24 in. ) of soil graded at a slope between 3 and 5 percent. Because the design of the final cover must consider the site, the weather, the character of the waste, and,other site-specific conditions, these minimum recommendations may be altered. Design innovation is encouraged to meet site specific criteria. For example, in extremely arid regions, a gravel top surface might compensate for reduced vegetation, or the middle drainage layer might be expendable. Where burrowing animals might damage the geomembrane/low- permeability soil layer, a biotic barrier layer of large-sized cobbles may be needed above it. Where the type of waste may create gases, soil or geosynthetic vent structures would need to be included. Cover Systems for Nonhazardous Waste The cover system in nonhazardous waste landfills will be a function of the bottom liner system and the liquids management strategy for the specific site. If the bottom liner system contains a geomembrane, then the cover system should contain a geomembrane to prevent the "bathtub" effect. Likewise, if the bottom liner system is a natural soil liner, then the cover system barrier should be hydraulically equivalent to or less permeable than the bottom liner system. A ------- vegetation/soil top layer drainage layer low-permeability geomembrane/ soli layer waste Jiz_ 60cm (24 in.) . ~~ -*- filter layer 30cm (12 in.) _^ 0.5-mm (20-mil) 60cm (24 in.) .^membrane Figure 3, USEPA-Recommended Landfill Cover Design. 158 ------- geomembrane used in the cover will prevent the infiltration of moisture to the waste below and may contribute to the collection of waste decomposition gases, therefore necessitating a gas collection layer. There are at least two options to consider under a liquids management strategy, mummification and recirculation. In the mummification approach the cover system is designed, constructed, and maintained to prevent moisture infiltration to the waste below. The waste will eventually approach and remain in a state of "mummification" until the cover system is breached and moisture enters the landfill. A continual maintenance program is necessary to maintain the cover system in a state of good repair so that the waste does not decompose to generate leachate and gas. t The recirculation concept results in the rapid physical, chemical, and biological stabilization of the waste. To accomplish this, a moisture balance is maintained within the landfill that will accelerate these stabilization processes. This approach requires geomembranes in both the bottom and top control systems to prevent leachate from getting out and excess moisture from getting in. In addition, the system needs a leachate collection and removal system on the bottom and a leachate injection system on the top, maintenance of this system for a number of years (depending on the size of the facility), and a gas collection system to remove the waste decomposition gases. In a modern landfill facility, all of these elements, except the leachate injection system, would probably be available. The benefit of this approach is that, after stabilization, the facility should not require further maintenance. A more important advantage is that the decomposed and stabilized waste may .be removed and used like compost, the plastics and metals could be recycled, and the site used again. If properly planned and operated in this manner, fewer landfill cells could serve much of a community's waste management needs for many years. In nonhazardous municipal solid waste landfills natural soils have been used for daily and final covers. However, the use of man made ..materials such as foams, recycled paper mixed with polymers, geosynthetics, etc. are gaining popularity for use as daily cover soils. When using natural soils as either the daily or final cover material, it is sometimes necessary to consider different material characteristics to satisfy site specific criteria. A matrix of soil characteristics and health, aesthetics, and site usage characteristics can be developed to provide information on which soil or combination of soils will be the most beneficial. GEOSYNTHETIC OPPORTUNITIES While the regulations require specific uses of selected geosynthetics in construction of waste management facilities, other opportunities exist that require attention. Figure 4 illustrates a schematic of a landfill, both liner and cover systems. The expanded use of geosynthetics could turn a marginal site into an acceptable site. Current Use ofGeosvnthetrcs Geotextiles, both woven and non-woven, could be used as separation, filtration, reinforcement, protection, drainage and erosion control only to mention a few ------- Geocomposlte/ Geonet Drain Geomambfans Geogrld Reinforcement Geosynlhetlc Erosion Control Systems Geogrld/Geotextlle Reinforcement Geolexllle Fitter Geocomposlie/ Geonet Drain Geomembrane UJ Geosynthellc Clay Liner J . Geotextlle Gas Vent jS u z: H- _ f_ UJ _ rs <_ o u. *( UJ 2 3C U. z u, ' >- tE Geotexllla Filter o 2 UJ <£ CD S Gravel w/Perforaled Pipe Geotexlile Protection Geomembrana (Primary) ** Geosynlhetlc Clay Liner Gootextlle Filter Geonet Leak Detection Geomembrane (Secondary) Compacted Clay Unef o: to ------- uses. In some designs, geotextiles are used with other products to form composites. These new composites now form multiple functions. Geotextiles are also being used as alternative daily cover materials at municipal solid waste landfills. The traditional 15cm (6in) soil daily cover consumes a significant amount of free air space in the life of a landfill. Geosynthetics multiple use can offer many of the same advantages of natural soils while being able to be reused for several weeks. There are some issues that have been raised when using geosynthetics. The use of geosynthetics was questioned when precipitation and freezing temperatures were expected. There is also a concern that when the geosynthetic was no longer useable whether to leave it in place and bury solid waste on top (concern: potential slope failure) or to bunch it up and bury it. The latter is the current practice. Geogrids are used primarily for reinforcement. As designers are increasingly challenged to increase free air space, increase side slope (and stability), to reuse or add to existing sites (vertical expansion) the use of geogrids to perform the required stability issues will be incorporated into the designs. Central to their use is the development of adequate design tests and consistent quality products. Geonets were used early in the designs of waste management facilities for drainage and leakage control and for gas venting in municipal facilities. Their high liquid and vapor transmission properties make them the material of choice, especially when compared to natural stone. Their rapid deployment and chemical resistance has increased the use of this product. Geomembranes was most likely the driving force in increased use of geosynthetics in the United States and now the world. Geomembranes are used primarily as liquid and vapor barriers for containment. Available in many different polymers, construction (reinforced and unreinforced), thicknesses, colors and their relative ease of installation has developed an industry that has had substantial growth over the last few years. Again familiarization with these products, improved resins, improved field seams and improved design knowledge has added increasingly to the use of these materials. Twenty years ago the industry was struggling with identify. Now the general public demands their use in containment systems. Geomats have not been as popular product in the waste industry as some of the other geosynthetics. Used primarily as erosion control the product is used primarily in agricultural and other civil engineering applications. Geopipes are used to convey liquids, primarily leachate, out of waste facilities. Different designs (smooth or corrugated), wall thickness and polymer type has created a_product that the designer is very willing to use. Improved design calculations for larger deeper landfills are currently being researched. Future Use of Geosvnthetics In order to improve or increase the use of geosynthetics in the waste management industry and in other engineering applications, there are several areas to consider. Perhaps the single most important issue is the design community itself. Only a very few select Universities have any formal training on ------- designing with geosynthetics. In fact most schools do not have any course work at all. The end result we are graduating engineers that do not know about geosynthetics, their use and limitations, their testing, or their design. We as an industry should strive to correct this deficiency. Fabric and polymer experts should join civil and environmental engineers to educate students, conduct joint research and to develop new products. Next is the materials themselves. Generally speaking, design engineers will use materials they understand and have design data for. Again the industry is in an excellent position to provide this guidance. As an example, the fabric engineer could work with civil/environmental engineers to study the design of materials for the best combination of strength and aperture size. The joint effort could be further expanded to improve the design of the stitching of the fabrics.1 The stitch design has been demonstrated (New Jersey dredge spoils/land reclamation project) to change the performance of high performance geotextiles. Perhaps the industry should develop an organization where all design data can be assembled in an unbiased manner, that is kept current (critical in this rapid growth industry) and to be made available to the design community. Thirdly, the design community needs to publish successful and in some cases unsuccessful designs. These designs will demonstrate to others how to design with geosynthetics, limitations and could encourage others to become involved with geosynthetics. Of particular interest to our industry is the long-term performance of materials. Our concerns are the resistance to chemicals, bio- and photo-degradation during construction and service. Up until about the early 1980's, the literature on geosynthetic applications was sparse. However, since then we have seen an explosion of articles from the classic designs and applications to some very unique and bold approaches on using geosynthetics. Last but not least we need to learn from our mistakes so that others do not follow in our foot steps. We need to encourage, npi chastise, designs or materials. By performing autopsies on decommissioned facilities, enormous information on design, durability, performance, weak/strong points, etc. can be realized. Publishing results will demonstrate to the general public that the industry is not hiding information but learning from past mistakes. s CONSTRUCTION QUALITY CONTROL AND QUALITY ASSURANCE Field data studies have clearly indicated that with the development of a construction quality control/quality assurance (CQA/CQC) program that the performance of the waste management facility will improve over a facility constructed without a good CQA/CQC program. CQA consists of a series of planned observations and tests required to insure that the final product (the waste management facility) will meet the project specifications. CQA is a management tool and the plans, specifications, observations, and tests are all used to provide a quantitative means of acceptance of the final product. CQC consists of a series of actions which provide a continuing means of measuring and controlling the characteristics of the product in order to meet the specifications of the finished product. CQC is the production tool that is / '0 ------- employed by the manufacturer of materials and contractor installing the materials at the site. The CQA/CQC plans are implemented through inspection activities which include visual observations, field testing and measurements, laboratory testing and the evaluation of the test data. The inspection activities are typically concerned with three separate functions: Quality control inspection by the manufacturer provides a real time measure of the quality of the product and the conformance with the project plans and specifications. Typically, the manufacturer will provide the CQC test results and a certification of the conformance of the product with the project plans and specifications for the manufactured materials, Quality control inspection by the contractor provides a real time measure of the quality of construction and the conformance with the project plans and specifications. This allows the contractor to correct the construction process if the quality of the product is not meeting the specifications and plans. CQC is performed independently of the CQA Plan. Quality assurance testing by the owner (acceptance inspection) performed by the owner usually through the third party testing firm, provides a measure of the quality of the final product and the conformance with the project plans and specifications. Due to the size and costs of a typical construction project, rejection of the - project at completion would be costly to all parties. Consequently, this testing takes place throughout the construction process. This allows deficiencies to be found and corrected before they become too large and costly. The CQA/CQC plan will require the development of the following key items: » Responsibility and Authority - The responsibility and authority of organizations and personnel involved in permitting, (if necessary), designing, and constructing the facility should be described in the CQC/CQA plans. « Personnel Qualifications - The qualifications of the CQA officers and supporting CQA inspection personnel should be presented in the CQC/CQA plans. . Inspection Activities - The observations and test that will be used to ensure that the construction or installation meets or exceeds all design criteria, plans, and specifications for each component should be described in the CQC/CQA plans. Sampling Strategies - The sampling activities, sample size, methods for determining sample locations, frequency of sampling, acceptance and rejection criteria, and methods for ensuring that corrective measures are implemented should be presented in the CQC/CQA plans. ------- Documentation - Reporting requirements for CQA activities should be described in detail in the CQC/CQA plans. Preconstruction meetings will be necessary to identify all key actors and their authority. This meeting should also develop a complete understanding of the intent of the above criteria. Discussion on specific issues should be finalized before construction begins so as not to delay the overall construction process. TECHNICAL GUIDANCE DOCUMENTS The U.S. Environmental Protection Agency, in support of hazardous and nonhazardous waste management facilities, developed three types of documents. The intent of these documents were to assist designers of facilities and reviewers of permits for these facilities. One document, the permit guidance manual addresses the type of information required for a permit. The other two documents, the Technical Resource Documents and the Technical Guidance Document, contain information useful to designers. The Technical Resource Documents present summaries of state-of-the-art technologies and evaluation techniques determined by the Agency to constitute good engineering designs, practices, and procedures. They describe current technologies and methods for -waste facilities, or for evaluating the performance of a facility design. Although emphasis is given to hazardous waste facilities, the information presented in these TRDs may be used for designing and operating nonhazardous waste treatment, storage and disposal facilities. The Technical Guidance Documents present design and operating parameters or design evaluation techniques that, if followed, would demonstrate compliance with the United States regulations. In addition to the documents described above the Agency presents detailed seminars throughout the U. S. Seminar publications', developed from these seminars, provide additional information useful to designers, operators and owners of waste management facilities. A listing of currently available documents is provided in the reference section. SUMMARY Management of hazardous and nonhazardous wastes will require the development of liner and cover systems that will minimize the release of potential pollutants to the environment. These systems, as designed and constructed in the United States, will contain mixtures of geosynthetics and natural soil materials. These designs have been generally described. The geosynthetic industry has risen to the challenge of developing products that improve the design requirements. Increasing the use of geosynthetics still further is an increased awareness in the University system, centralized data bases that are current, publishing of successful/unsuccessful geosynthetic projects and performing case studies at decommissioned sites. The future is very bright but needs the commitment of industry to keep it burning. ------- To insure that the facilities are constructed as designed, the development of a CQA/CQC plan is recommended. Specific objectives as well as key elements of the plan have been provided. Finally, the technical knowledge, presented through a series of documents and publications have been identified. REFERENCES U.S. EPA, "Design, Construction and Maintenance of Cover Systems for Hazardous Waste, An Engineering Guidance Document," U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS, May 1987, NTIS PB 87-191656. U.S. EPA, "Evaluating Cover Systems for Solid and Hazardous Waste," Office of Solid Waste and Emergency Response Washington, D.C., SW 867, September 1982, NTIS PB 87-154894. U.S. EPA, "Construction Quality Assurance for Hazardous Waste Land Disposal Facilities," Office of Solid Waste and Emergency Response, Washington, D.C. EPA/530-SW-86-031, OSWER Policy Directive No. 9472.003, NTIS PB 87-132825. U.S. EPA, "Design, Construction, and Evaluation of Clay Liners for Waste Management Facilities," Technical Resource Document, Hazardous Waste Engineering Research Laboratory, Office of Research and Development, U. S. Environmental Protection Agency, Cincinnati, OH, EPA/530-SW-86-007F, September 1988, NTIS PB 86-184496. U.S. EPA, "Lining of Waste Containment and Other Impoundment Facilities," Technical -Resource Document, EPA-600/2-88-052, September 1988, NTIS PB-129670. Moore, Charles A., "Landfill and Surface Impoundment Performance Evaluation," U.S. EPA SW-869, 1982, NTIS PB 81-166357. Richardson and Koerner, "Geosynthetic Design Guidance for Hazardous Waste Landfill Cells and Surface Impoundments," EPA-600/2-87-097, December 1987, NTIS PB 88-131263. s U.S. EPA, "Guide to Technical Resources for the Design of Land Disposal Facilities," Risk Reduction Engineering Laboratory and Center for Environmental Research Information, EPA/625/6-88/018, Cincinnati, OH, 1988. U.S. EPA, "Seminar Publication; Requirements for Hazardous Waste Landfill Design, Construction and Closure", Center for Environmental Research Information, EPA/625/4-89/002, Cincinnati, OH, 1989. U.S. EPA, "Technical Guidance Document; Final Covers on Hazardous Waste Landfills and Surface Impoundments" Office of Research and Development, EPA/530-SW-89-047, Cincinnati, OH, July 1989. U.S. EPA, "Technical Resource Development; Design, Construction and Operation of Hazardous and Nonhazardous Waste Surface impoundments," Office of Research and Development, EPA/530/SW-91/054, Cincinnati, OH, June 1991. A.3 ------- U.S. EPA, "Technical Guidance Document; Inspection Techniques for the Fabrication of Geomembrane Field Seams" Office of Research and Development, EPA/530/SW- 91/051, Cincinnati, OH, May 1991. U.S. EPA, "Seminar Publication; Design, Construction of RCRA/CERCLA Final Covers," Center for Environmental Research Information, EPA/625/4-91/025, Cincinnati, OH, May 1991. U.S. EPA, "Alternative Daily Cover Materials for Municipal Solid Waste Landfills" U.S. EPA - Region IX, EPA/530/R29/024, NTIS-PB92-208206 ------- EPA/600/A-92/273 TECHNICAL REPORT DATA (Please read Instruction! on the rcvenc before complcr 1. REPORT NO. 2. 3. 4. TITLE AND SUBTITLE 5. REPORT DATE Opportunities for Use of Geosynthetics in Waste Management Facilities 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) Robert E. Landreth 8. PERFORMING ORGANIZATION REPORT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS USEPA/RREL/WMDDRD/MSWRMB 5995 Center Hill Ave. Cincinnati, OH 45224 10. PROGRAM ELEMENT NO. 11. CONTRACT/GRANT NO. 12. SPONSORING AGENCY NAME AND ADDRESS Risk Reduction Engineering Laboratory--Cinti, OH Office of Research and Development U.S. Environmental Protection Agency Cincinnati, OH 45268 13. TYPE OF REPORT AND PERIOD COVERED published paper 14. SPONSORING AGENCY CODE EPA/600/14 is.SUPPLEMENTARY NOTES Project Officer = Robert L. Landreth'lbl-})bby-/bvi 2nd International High-Performance Fabrics Conf Proceedings, November 12-13,1992, Boston, Massachusetts, p:153-166 16. ABSTRACT The USEPA through its research and field experiences has developed control strategies for hazardous and municipal solid waste landfills and surface impoundments. These control strategies include liner and cover systems. The liner systems include double liners for hazardous waste and a single composite liner for municipal solid waste. The purpose of each individual component will be discussed with options for using natural in-situ materials or geosynthetics. Although natural soils are used as various components, emphasis has been placed on the use of geosynthetics, including geomembranes, geonets, geotextiles, and plastic pi'pes. Cover systems for both hazardous and municipal waste facilities are based on a multilayer design. The multilayer component characteristics, including performance, thickness, and material type will be discussed. These designs include both natural soils and geosynthetics. It has been demonstrated with field data that the development of construction quality control/quality assurance will improve the performance of the disposal facility The improved performance of the waste management facility reinforces the confidence of designers as they understand the limits of designing with geosynthetics. 17. KEY WORDS AND DOCUMENT ANALYSIS DESCRIPTORS b.lDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group geosynthetics municipal solid waste landfills liner systems cover systems REPRODUCED BY U.S. DEPARTMENT OF COMMERCE NATIONAL TECHNICAL INFORMATION SERVICE SPRINGFIELD, VA. 22161 18. DISTRIBUTION STATEMENT RELEASE TO PUBLIC 19. SECURITY CLASS (This Report! UNCLASSIFIED 21. NO. OF PAGES 16 20. SECURITY CLASS (This page) UNCLASSIFIED 22. PRICE EPA Form 2220-1 (R«v. 4-77) PREVIOUS EDITION is OBSOLETE ------- |