Advanced hydraulic fracturing methods to create in situ reactive barriers

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:576574

Murdoch, L ^[1]; Siegrist, B ^[2]; Vesper, S ^[3]

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1. FRx Inc., Cincinnati, OH (United States)
2. Oak Ridge National Lab., TN (United States)
3. Univ. of Cincinnati, OH (United States); and others

Many contaminated areas consist of a source area and a plume. In the source area, the contaminant moves vertically downward from a release point through the vadose zone to an underlying saturated region. Where contaminants are organic liquids, NAPL may accumulate on the water table, or it may continue to migrate downward through the saturated region. Early developments of permeable barrier technology have focused on intercepting horizontally moving plumes with vertical structures, such as trenches, filled with reactive material capable of immobilizing or degrading dissolved contaminants. This focus resulted in part from a need to economically treat the potentially large volumes of contaminated water in a plume, and in part from the availability of construction technology to create the vertical structures that could house reactive compounds. Contaminant source areas, however, have thus far remained largely excluded from the application of permeable barrier technology. One reason for this is the lack of conventional construction methods for creating suitable horizontal structures that would place reactive materials in the path of downward-moving contaminants. Methods of hydraulic fracturing have been widely used to create flat-lying to gently dipping layers of granular material in unconsolidated sediments. Most applications thus far have involved filling fractures with coarse-grained sand to create permeable layers that will increase the discharge of wells recovering contaminated water or vapor. However, it is possible to fill fractures with other compounds that alter the chemical composition of the subsurface. One early application involved development and field testing micro-encapsulated sodium percarbonate, a solid compound that releases oxygen and can create aerobic conditions suitable for biodegradation in the subsurface for several months.

• Research Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 576574
• Report Number(s): CONF-970208--Proc.; ON: DE98001967
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROBIC CONDITIONS
BIODEGRADATION
CONTAINMENT SYSTEMS
HYDRAULIC FRACTURING
LAYERS
PERFORMANCE
PLUMES
POLLUTION CONTROL
SEDIMENTS
SOILS