It was in 1991 that the Environmental Protection Agency promulgated its Criteria for Municipal Waste Landfills that set location restrictions, design and operating standards, groundwater monitoring requirements, corrective actions, closure requirements, and more for landfills. It was these rules that mandated that landfills be lined on the sides and bottom before waste is deposited and capped on the surface when closed.
In Kentucky, a county board votes to shut down a landfill that had long been the source of odor complaints from nearby residents. In Hawaii, residents push a city council to expedite a delayed landfill closure. Outside Beirut, Lebanon, protesters try to block trucks entering a landfill they say should have been closed a week earlier. These events, while certainly newsworthy, obscure the fact that when they are over the real work has to begin. (more…)
Geomembranes, predominately linear low-density polyethylene (LLDPE), have been used for landfill caps for decades. Waste Management World has noted how,” Generally they have performed extremely well but, not unexpectedly, there have been a few exceptions that have guided us in developing even better systems.” Currently, there are four commonly used options for landfill caps, each with their plusses and minuses, especially with respect to stability.
What is leachate? In a lab, it is any liquid that extracts solids as it passes through matter. In a landfill, it is the water that enters the facility in a number of ways, passes through waste material on contact, contains a wide range of constituents, and must be addressed with a proper operations plan. Leachate treatment options and mitigation are one of the greatest costs for landfill operators today.
Some 40 percent of the geosynthetics manufactured today are used by the mining industry, according to one estimate, and there are predictions that figure will increase as the industry continues to adopt mining technologies that help improve efficiency and protect the environment.
The majority of slope failures within the geosynthetics industry can often be avoided with proper engineering and material selection. However, the factors that affect slope stability can be difficult to discern and measure. Soil thickness, seepage forces, seismic forces, gas uplift, geomembrane texturing, engineering and provision of reinforcing elements are only a few of the factors affecting slope stability. Many failures occur at interfaces with geosynethics and most notably at the geomembrane/geotextile interface or geotextile/soil interface. (more…)
Creep, the tendency of materials to deform over time due to applied stresses, has been a focus of the geosynthetics industry since testing first began more than 25 years ago. Creep testing methods have evolved, but the accurate assessment of tension creep (along with transmissivity) remains essential to the product evaluations of organizations considering geomembrane/geocomposite drainage systems.
The EPA’s RE-Powering America’s Land Initiative is picking up steam. The effort, launched in 2008, encourages the reuse of contaminated lands, landfills and mine sites for renewable energy generation. The agency’s Action Plan 2.0, released last fall, details how far the program has come and what is being done to expand it.