Subscribe to our free daily newsletters
. Earth Science News .




Subscribe to our free daily newsletters



New Cleanup Project Builds Upon Success Gained In Field
Microorganisms found in subsurface environments can transform radionuclides such as uranium, technetium and other contaminants like nitrate into chemical forms that are less mobile in groundwater
Microorganisms found in subsurface environments can transform radionuclides such as uranium, technetium and other contaminants like nitrate into chemical forms that are less mobile in groundwater
by Staff Writers
Oak Ridge TN (SPX) Dec 18, 2006
A new five-year project headed by Oak Ridge National Laboratory is expected to lead to a more in-depth understanding of natural and other approaches to clean up contaminated sites around the nation.

The Department of Energy-funded $3 million per year task will build upon accomplishments since April 2000 at the Environmental Remediation Science Program Field Research Center, a 243-acre contaminated area in Bear Creek Valley next to the Oak Ridge Y-12 National Security Complex. This and many other sites in the United States are contaminated with legacy wastes that include radionuclides, organics and nitrate.

"Our goal is to more accurately determine the long-term fate of contaminants from waste sites around the country," said David Watson, manager of DOE's Field Research Center and a member of the Environmental Sciences Division. "Through this effort we will bring to bear experts from multiple universities and national laboratories to help solve a problem of great national significance."

Researchers from ORNL and elsewhere plan to develop numerical models that will allow them to predict the rate at which contaminant concentrations decrease through a combination of active remediation techniques and natural mechanisms such as dilution. Bioremediation, one of the remediation methods being tested, involves stimulating bacterial growth in the subsurface to clean up contaminants and may provide a more economical and effective approach than more conventional methods.

Researchers will make chemical additions and pH adjustments to help develop new methods to stabilize contaminants in the subsurface. New state-of-the-art analysis techniques are being developed to monitor changes in microbial populations and geochemical properties. Changes in the subsurface are being monitored using geophysical methods that send electric, acoustic and other signals into the ground.

Nationwide, this DOE effort is expected to have a huge impact as subsurface contamination exists at more than 7,000 sites and involves an estimated 1.7 trillion gallons of contaminated water, which is equal to about four times the daily water consumption in the United States. In all, there are about 40 million cubic meters of contaminated soil, or enough dirt to fill approximately 17 professional sports stadiums.

The Y-12 site contains uranium, technetium, nitrate and other contaminants from the weapons manufacturing era from 1951 to 1983. These liquid wastes were disposed of in four ponds during that era. The pond area, which is 400-by-400 feet and 17 feet deep, was neutralized in 1984 and capped by an asphalt parking lot in 1988. As a result of these waste disposal activities, a large plume of contaminated groundwater extends several miles away from the ponds.

The area is constantly monitored using a variety of state-of-the-art techniques, including hydraulic testing, tracer tests and sampling.

"At no other field research facility is the investigation of the subsurface fate and transport of contaminants performed on such a large scale using a real-world contaminated site," Watson said.

Key conclusions from research projects at the site include:

-- microorganisms found in subsurface environments can transform radionuclides such as uranium, technetium and other contaminants like nitrate into chemical forms that are less mobile in groundwater;

-- the introduction of naturally occurring humic substances - organic matter found in soil - can accelerate the chemical reduction and immobilization of these contaminants; and,

-- co-contaminants in the subsurface and elevated concentrations of other chemicals can inhibit the chemical reduction process and can reoxidize uranium, making it more mobile.

Watson and colleagues are confident that this new project will lead to new methods of site remediation and a fundamental scientific understanding of the long-term fate, transport and attenuation of contaminants in the environment as a function of space and time.

Other partners in this project, funded by DOE's Office of Science, are the University of Tennessee, Stanford University, Florida State University, the University of Oklahoma, Lawrence Berkeley and Argonne national laboratories. UT-Battelle manages Oak Ridge National Laboratory for DOE.

Related Links
Oak Ridge National Laboratory

Underground Air Might Cause DNA Damage
Karolinska, Sweden (SPX) Dec 18, 2006
Our everyday environments are full of airborne particles that are harmful to varying degrees when inhaled. Particularly damaging to our cellular DNA are the particles from the underground system in Stockholm, Sweden, according to a new doctoral thesis from Karolinska Institutet.







  • Analysis: Clooney expands Darfur effort
  • Aceh Still Lacks Long-Term Plan For Tsunami Recovery
  • New Orleans Remains Vulnerable To Flooding
  • Japan Tightens Building Rules After Quake Scandal

  • Overconfidence Leads To Bias In Climate Change Estimations
  • 2006 Set To Be Sixth Warmest On Record Says WMO
  • Gingerbread Houses Latest Victim Of Global Warming
  • Global Warming Of The Future Is Projected By Ancient Carbon Emissions

  • Europe Ready To TANGO With New EO Constellation
  • COSMIC Provides Better Weather Forecasts, Climate Data
  • China To Launch 22 More Meteorological Satellites By 2020
  • Jason-1 Celebrates Five Years In Orbit - Ocean Data Continues To Flow

  • Easy Come, Easy Go: Shell And Sakhalin
  • Stripes And Superconductivity - Two Faces of the Same Coin
  • Russian Capabilities Benefit The Hydrogen Economy
  • Ethylene Suggested For Hydrogen Storage

  • Malaria Kills 21 People In Flood-Hit Somalia, Toll Climbs To 141
  • Common PTSD Drug Is No More Effective Than Placebo
  • Freed China Activist Says AIDS Problem Far Exceeds Official Data
  • Africa Urged To Break Deafening Silence On AIDS

  • What is Life
  • NASA Ice Images Aid Study Of Pacific Walrus Arctic Habitats
  • Tiny Bones Rewrite Textbooks
  • Extreme Life, Marine Style, Highlights 2006 Ocean Census

  • Underground Air Might Cause DNA Damage
  • New Cleanup Project Builds Upon Success Gained In Field
  • Yellow River Pollution Getting Worse
  • Asian Cities Face Environmental Crises

  • Ancient Ape Ruled Out Of Man's Ancestral Line
  • Concrete Blocks Used In Great Pyramids Construction
  • Gendered Division Of Labor Gave Modern Humans Advantage Over Neanderthals
  • Genetic Variation Shows We're More Different Than We Thought

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement