Tackling environmental challenges with specialized techniques and tools
In work performed for the U.S. Department of Energy (DOE) in fiscal year 2011—as part of the DOE Oak Ridge Office’s efforts to reduce the number of radiologically and chemically contaminated facilities on the Oak Ridge Reservation—ORAU applied several specialized techniques and tools to address various project challenges.
ORAU used specialized equipment to perform characterization surveys of indoor facilities not accessible using Global Positioning Systems.
One of the challenges presented was the characterization of DOE’s 2.8-million-square-foot facility known as K-33, which was formerly used to house a uranium-enrichment operation during the Manhattan project. The characterization, completed in FY11, required ORAU to map the interior of the structure—floors, walls and ceilings—to provide DOE information on the nature and extent of radiological and chemical contamination at hundreds of sample and measurement locations. For part of this work, the ORAU project team had to look beyond standard characterization equipment, which utilizes global positioning systems to capture the location and scan information. Because this project was indoors, the building’s structure blocked the GPS signal. To solve the problem, the project team combined off-the-shelf land survey technology to provide the x-y-z coordinates with a standard radiation ratemeter and then developed a software package that allowed the two systems to communicate with each other. The resulting equipment generated a three-dimensional map from within the building that precisely showed the locations and levels for the existing radiological contamination.
ORAU also incorporated a versatile industry tool—X-ray fluorescence—in another DOE-related project requiring some initial characterization work at the Y-12 National Security Complex’s 81-10 area, a former mercury recovery and storage site. For this project, the team incorporated X-ray fluorescence analysis, in the form of a portable, handheld device, for subsurface soil investigations to help determine the nature and extent of mercury contamination. Analyzing soil cores in one-foot intervals from approximately 30 borehole locations resulted in more than 900 individual XRF measurements. The XRF provided immediate data during field screening, which saved laboratory analytical costs.
Another technique used by ORAU, called waste lot profiling, can be used to characterize the level and type of contamination found in an existing building that is scheduled for demolition or a site where demolition has occurred. This process, when successfully applied, can save customers both money and time by providing them an accurate picture of the waste lot’s content, enabling them to make faster, well- informed decisions about how the waste should be handled per federal and local regulations. For example, in recent work for DOE, ORAU used this technique on approximately 164,000 tons of hazardous material from K-33 to assess for proper disposition. The project team compiled the waste profiles by gathering anecdotal evidence and field data collected through activities such as nondestructive testing and intrusive sample results. Beyond the tangible savings of time and money, effective applications of waste lot profiling allowed for better protection of personnel by lowering the risk of encountering unknown contaminants.
164,000
tons of hazardous material
Through the use of these and other tools and techniques, ORAU customers have realized projects savings in both time and money. For DOE alone, performing upfront characterization on K-33 saved more than $1.7 million, while other work by ORAU shaved six to 12 months off the time needed have a project “shovel-ready” for demolition.