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Title: Waste reduction by separation of contaminated soils during environmental restoration

Conference ·
OSTI ID:658205
; ; ;  [1];  [2];  [3]
  1. Sandia National Labs., Albuquerque, NM (United States)
  2. GRAM, Inc., Albuquerque, NM (United States)
  3. Technadyne Engineering Consultants, Inc., Albuquerque, NM (United States)

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill.

Research Organization:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
USDOE Office of Environmental Restoration and Waste Management, Washington, DC (United States)
DOE Contract Number:
AC04-94AL85000
OSTI ID:
658205
Report Number(s):
SAND-98-0529C; CONF-980654-; ON: DE98005532; BR: EW2010202; TRN: 98:011229
Resource Relation:
Conference: 14. DOE pollution prevention conference, Seattle, WA (United States), 2-4 Jun 1998; Other Information: PBD: Jun 1998
Country of Publication:
United States
Language:
English