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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Nandan G. Chandregowda, Sunil S. Chirayath, William S. Charlton, Young Ham, Shiva Sitaraman, Gil Hoon Ahn
Nuclear Technology | Volume 184 | Number 3 | December 2013 | Pages 320-332
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-A24989
Articles are hosted by Taylor and Francis Online.
Korea Hydro and Nuclear Power has built a new modular type of CANDU spent fuel bundle dry storage facility, MACSTOR KN-400, at the Wolsong reactor site in the Republic of Korea. Four CANDU reactors operate at the Wolsong site, and the MACSTOR KN-400 has the capacity to store up to 24 000 CANDU spent fuel bundles. The International Atomic Energy Agency safeguards regulations demand an effective method for spent-fuel re-verification at the MACSTOR KN-400 facility in the event of any loss of continuity of knowledge. A radiation signal-dependent spent-fuel re-verification design of the MACSTOR KN-400 is scrutinized through mathematical model development and Monte Carlo radiation transport simulations using the state-of-the-art computer code MCNP. Both gamma and neutron transport simulations for various spent fuel bundle diversion scenarios are carried out for the central and corner re-verification tube structures. The CANDU spent fuel bundles with a burnup of 7500 MWd/tonne U (burned at a specific power of 28.39 MW/tonne) and 10 years of cooling time are considered for the radiation source term. Results of the gamma transport simulations incorporating cadmium-zinc-telluride detectors inside the re-verification tube show that spent fuel bundles diverted from the inner locations of the storage basket cannot be detected by observing a gamma radiation signal change. Neutron transport simulations consisting of a 3He detector inside the re-verification tube show that certain spent fuel bundle diversions could be detected. However, inverse MCNP neutron transport simulations show that the possibility of detecting diversion of [approximately]67% of spent fuel bundles stored in the basket region on the opposite side from the collimator of the re-verification tube is small, assuming a neutron detection counting time of 1 h per re-verification tube. It is also observed that the nondetection probability for most of the diversion scenarios considered is large. Nondetection probability here is defined as the probability of not detecting the diversion of spent fuel bundles from the baskets by observing radiation signal reduction from the removal of the bundles. Containment and surveillance methods are being employed for safeguards purposes at the facility, supplemented by periodic axial profile fingerprinting. However, since the nondetection probability is large for most scenarios, the facility should consider alternatives to this method in case loss of continuity of knowledge occurs.