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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Robert D. Holmes, Gary W. Frank
Nuclear Technology | Volume 87 | Number 2 | October 1989 | Pages 545-552
Technical Paper | TMI-2: Health Physics and Environmental Release / Technique | doi.org/10.13182/NT89-A27751
Articles are hosted by Taylor and Francis Online.
Recovery, defueling, and restoration of Three Mile Island Unit 2 (TMI-2) to an environmentally stable configuration has been a labor-intensive effort that had to be conducted in complex radiological conditions of varying field intensities. Part of the success of the TMI-2 Radiological Controls Program in minimizing worker exposure can be attributed to the effective use of a variety of portable instruments. Systematic surveys were conducted to quantify general radiation fields, locate hot spots, and establish surface contamination levels and airborne concentrations of radionuclides. Detailed and accurate radiological surveys and field measurements are essential to as low as reasonably achievable reviews, radiation work permit specifications for protective measures, and job briefings. Radiological instruments used at TMI-2 include a variety of devices capable of assessing radiation fields from sealed sources, contaminated surfaces, and airborne radioactivity. A major effort in the recovery process was the systematic characterization of contamination levels throughout the reactor and auxiliary buildings. At TMI-2, a fast sorting measurement technique was developed to identify and prioritize surfaces for exposure reduction and to rapidly evaluate effectiveness of decontamination efforts. Standard vendor-supplied instruments such as the Eberline HP-220-A and the RO-7 had to be modified in their respective directional sensitivity. Decontamination techniques also required extensive monitoring for airborne levels of various radionuclides. Area air samples and breathing zone air samplers were used extensively to assess for potentially respirable radioactivity. To optimize detection of personnel skin and clothing contamination, pancake probe friskers were largely replaced or supplemented by automated personnel contamination monitors. At TMI-2, the maintenance and calibration of radiological instruments are conducted on-site by a group of qualified technicians who are an integral part of the Radiological Controls Division. All calibration and repair are subject to a variety of audits, inspections, and internal and external assessments. Quality assurance auditors routinely verify compliance with station procedures, ensure that primary instruments are sent to accredited laboratories for calibration, and certify that calibration sources are traceable to the National Bureau of Standards.