◊ Air Sparging
◊ Bioreactor Landfills ◊ Bioremediation of Chlorinated Solvents ◊ Bioventing and Biosparging ◊ Electrokinetics: Electric Current Technologies ◊ Fracturing ◊ Ground-Water Circulating Wells ◊ In Situ Flushing ◊ In Situ Oxidation ◊ Multi-Phase Extraction ◊ Natural Attenuation ◊ Permeable Reactive Barriers ◊ Phytoremediation ◊ Remediation Optimization ◊ Soil Vapor Extraction ◊ Soil Washing ◊ Solvent Extraction ◊ Thermal Treatment: Ex Situ ◊ Thermal Treatment: In Situ Overview Fracturing is a way to crack rock or very dense soil, like clay, below ground. It is not necessarily a cleanup method in itself. Rather, fracturing is used to break up the ground to help other cleanup methods work better. The cracks, which are called fractures, create paths through which harmful chemicals can be removed or destroyed. Hydraulic fracturing uses a liquid—usually water. The water is pumped under pressure into holes drilled in the ground. The force of the water causes the soil (or sometimes rock) to crack. It also causes existing fractures to grow larger. To fracture soil at greater depths, sand is pumped underground with the water. The sand helps prop the fractures open and keep them from closing under the weight of the soil. Pneumatic fracturing uses air, to fracture soil. It also can help remove chemicals that evaporate or change to gases quickly when exposed to air. When air is forced into the soil, the chemicals evaporate and the gases are captured and treated above ground. Air can be forced into the ground at different depths within a hole. When air is forced near the ground surface, the surface around the holes may rise as much as an inch, but will settle back close to its original level. In both pneumatic and hydraulic fracturing, equipment placed underground directs the pressure to the particular zone of soil that needs to be fractured. Blast-enhanced fracturing uses explosives, such as dynamite, to fracture rock. The explosives are placed in holes and detonated. The main purpose is to create more pathways for polluted groundwater to reach wells drilled for pump and treat cleanup.
4.44 Hydrofracturing (In Situ Ground Water Remediation Technology)
4.7 Fracturing (In Situ Soil Remediation Technology)
Artificially-Induced or Blast-Enhanced Fracturing to Improve Groundwater Recovery for Treatment and Migration Control: Technology Overview Report The report introduces the principles and techniques associated with fracturing and discusses the advantages and disadvantages of the technology in remediation applications.
A Citizen's Guide to Fracturing The Citizen's Guide Series are 2-page fact sheets that provide a general description on approaches to clean up contaminated was sites. The fact sheets cover five questions about each clean up approach: What is it?, How does it work?, Is it safe?, How long will it take?, and Why use it?.
Guía para el Ciudadano sobre Fracturación La Serie de Guías del Ciudadano son boletines de dos páginas con datos que proveen una descripción general en cómo sanear sitios contaminados. Estos boletines con datos que cubren cinco preguntas acerca de cada procedimiento de saneamiento: ¿Qúe es?, ¿Cómo trabaja?, ¿Es seguro?, ¿Cúanto tiempo requerirá?, y ¿Por qué debe de usarse?
Treatment Technologies for Site Cleanup: Annual Status Report (ASR), Twelfth Edition The Twelfth Edition of this report, published by the EPA Office of Superfund Remediation and Technology Innovation (OSRTI) in September 2007, documents treatment technology applications at more than 1,900 soil and groundwater cleanup projects at National Priorities List (NPL) sites. The status of more than 1,200 projects included in the ASR Eleventh Edition is updated, and information about 192 new projects derived from Records of Decision (ROD) signed from 2002 through 2005 is added. The report also includes a special section about on-site containment remedies. The ASR is based on the analysis of nearly 3,000 RODs signed since 1982 at 1,536 NPL sites. The online version includes new downloadable spreadsheets with the data for several of the key tables and figures in the report. Specific information about each technology application included in the ASR Twelfth Edition is available in the ASR Remediation Database.
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