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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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After decades, Hanford’s WTP begins vitrifying tank waste
The Department of Energy’s Office of Environmental Management and its contractor Bechtel announced on October 15 the start of nuclear vitrification operations at the Waste Treatment and Immobilization Plant (WTP), also known as the Vit Plant, at the Hanford Site in Washington state.
R. J. Cerbone, R. E. Slovacek, E. R. Gaerttner
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 75-84
Technical Paper | doi.org/10.13182/NSE67-A17244
Articles are hosted by Taylor and Francis Online.
Position-dependent thermal spectra have been measured in a paraffin-moderated 235U multiplying assembly using two independent methods. Steady-state spectra were obtained with the time-of-flight technique employing a 24.40-m flight in conjunction with the Rensselaer Polytechnic Institute linear accelerator; asymptotic (in time) spectra were obtained with the pulsed-LINAC chopper technique. A new technique was developed to monitor the source intensity with a tracking reliability of ± 1.5%. The measured spectra are compared to a series of DTF-IV transport calculations using a P1 kernel and P1 source; the spatial source was obtained from a transport calculation. The spectrum calculations were performed with a polyethylene kernel utilizing either the Goldman model or the Koppel-Young four-oscillator model. The experimental spectra are generally in closer (better than 5%) agreement with calculations using the Goldman kernel than with those using the Koppel-Young kernel. This result is consistent with the total cross section of polyethylene measured by Armstrong.