Bioremediation of Hanford groundwater

Conference · Sun Sep 08 04:00:00 EDT 1991

OSTI ID:5192126

Brouns, T. M. ^[1]; Anderson, D. B. ^[1]; Fredrickson, J. K. ^[1]; Luttrell, S. P. ^[1]; Skeen, R. S. ^[1]; Workman, D. J. ^[1]

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1. Pacific Northwest Laboratory (PNL), Richland, WA (United States)

Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40 years of operations at the U.S. Department of Energy's (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate (NO₃^-), carbon tetrachloride (CCl₄), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and remediation of existing contaminated groundwaters may be required. A research and development program is underway to develop bioremediation technologies for both ex situ and in situ groundwater treatment. Although ex situ pump-and-treat remediation schemes have been criticized recently for their limited effectiveness in cleaning up contaminated aquifers to stringent regulatory standards, the use of extraction wells and above ground treatment can be effective in removing bulk quantities of contaminants from the subsurface. Extraction processes can also be used on an interim basis to control the migration of contaminants. An ex situ bioremediation technology is being developed to provide cost effective methods for treating extracted groundwater. An in situ treatment process is also being developed. The goal of this process is to stimulate the native microorganisms and accelerate the natural degradation of NO₃^- and CCl₄. In situ treatment offers the additional benefits of lower operating costs, better removal of sorbed contaminants, and lower potential for exposure of workers to hazardous chemicals. A demonstration site at Hanford for in situ biological treatment was selected in 1990, and extensive hydrological, chemical, and biological characterization of the site is underway. Current research and development activities are focusing on developing methods for supplying nutrients to the subsurface, evaluating the effect of in situ bioremediation on the long-term mobility of metal and radionuclide co-contaminants, and modeling the bioremediation process using three-dimensional visualization tools to help design the field-scale demonstration site and predict performance. The in situ bioremediation process will be developed and tested at the laboratory and intermediate-scale prior to field demonstration as part of the DOE's Integrated Demonstration for Cleanup of Volatile Organic Compounds at Arid Sites (VOC-Arid Integrated Demonstration).

• Research Organization: Pacific Northwest Laboratory (PNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5192126
• Report Number(s): PNL-SA--19646; CONF-910981--25; ON: DE92000799
• Country of Publication: United States
• Language: English

Related Subjects

054000 -- Nuclear Fuels-- Health & Safety
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
54 ENVIRONMENTAL SCIENCES
540350* -- Environment
Aquatic-- Site Resource & Use Studies-- (1990-)
AQUIFERS
CHEMICAL WASTES
ENVIRONMENTAL TRANSPORT
GROUND WATER
HANFORD RESERVATION
HYDROGEN COMPOUNDS
HYDROLOGY
ISOTOPES
LIQUID WASTES
MANAGEMENT
MASS TRANSFER
MATERIALS
NATIONAL ORGANIZATIONS
NONRADIOACTIVE WASTES
OXYGEN COMPOUNDS
PROCESSING
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTE PROCESSING
RADIOACTIVE WASTES
RADIOISOTOPES
RADIONUCLIDE MIGRATION
REMEDIAL ACTION
SITE CHARACTERIZATION
SOILS
US DOE
US ERDA
US ORGANIZATIONS
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
WATER