¹³⁷ Cs Activities and ¹³⁵ Cs/ ¹³⁷ Cs Isotopic Ratios from Soils at Idaho National Laboratory: A Case Study for Contaminant Source Attribution in the Vicinity of Nuclear Facilities

Journal Article · Tue Mar 03 00:00:00 EST 2015 · Environmental Science and Technology

DOI:https://doi.org/10.1021/es5058852· OSTI ID:1182692

Snow, Mathew S. ^[1]; Snyder, Darin C. ^[2]; Clark, Sue B. ^[3]; Kelley, Morgan ^[3]; Delmore, James E. ^[2]

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1. Washington State Univ., Pullman, WA (United States). Dept. of Chemistry; Idaho National Lab. (INL), Idaho Falls, ID (United States)
2. Idaho National Lab. (INL), Idaho Falls, ID (United States)
3. Washington State Univ., Pullman, WA (United States). Dept. of Chemistry

Radiometric and mass spectrometric analyses of Cs contamination in the environment can reveal the location of Cs emission sources, release mechanisms, modes of transport, prediction of future contamination migration, and attribution of contamination to specific generator(s) and/or process(es). The Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) represents a complicated case study for demonstrating the current capabilities and limitations to environmental Cs analyses. ¹³⁷Cs distribution patterns, ¹³⁵Cs/¹³⁷Cs isotope ratios, known Cs chemistry at this site, and historical records enable narrowing the list of possible emission sources and release events to a single source and event, with the SDA identified as the emission source and flood transport of material from within Pit 9 and Trench 48 as the primary release event. These data combined allow refining the possible number of waste generators from dozens to a single generator, with INL on-site research and reactor programs identified as the most likely waste generator. A discussion on the ultimate limitations to the information that ¹³⁵Cs/¹³⁷Cs ratios alone can provide is presented and includes (1) uncertainties in the exact date of the fission event and (2) possibility of mixing between different Cs source terms (including nuclear weapons fallout and a source of interest).

• Research Organization: Idaho National Lab. (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC07-05ID14517; 2012-DN-130-NF0001-02
• OSTI ID: 1182692
• Report Number(s): INL/JOU-14-31778; TRN: US1500196
• Journal Information: Environmental Science and Technology, Vol. 49, Issue 5; ISSN 0013-936X
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
IDAHO NATIONAL LABORATORY
CESIUM 137
CESIUM 135
MASS SPECTROSCOPY
ISOTOPE RATIO
FALLOUT
FLOODS
FORECASTING
MIXING
CONTAMINATION
FISSION
SOILS
RADIONUCLIDE MIGRATION
RADIOACTIVE WASTES
SOURCE TERMS
SPATIAL DISTRIBUTION
135Cs/137Cs
CESIUM-137
NUCLEAR FORENSICS
SDA