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2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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RIC session focuses on interagency collaboration
Attendees at last week’s 2026 Regulatory Information Conference, hosted by the Nuclear Regulatory Commission, saw extensive discussion of new reactor technologies, uprates, fusion, multiunit deployments, supply chain, and much more.
With the industry in a state of rapid evolution, there was much to discuss. Connected to all these topics was one central theme: the ongoing changes at the NRC. With massively shortened timelines, the ADVANCE Act and Executive Order 14300, and new interagency collaboration and authorization pathways in mind, speakers spent much of the RIC exploring what the road ahead looks like for the NRC.
Jin Beak Park, Yong Soo Hwang, Chul Hyung Kang
Nuclear Science and Engineering | Volume 142 | Number 2 | October 2002 | Pages 165-176
Technical Paper | doi.org/10.13182/NSE02-A2297
Articles are hosted by Taylor and Francis Online.
Matrix diffusion into a rock matrix has been regarded to retard radionuclide migration in a fracture. Recent field findings on a fractured system indicate that only a small portion of the rock in a fractured porous medium contributes to holding a radionuclide by matrix diffusion. To understand this effect, radionuclide migration in a fracture and diffusion from a finite rock matrix to a fracture are discussed with limited matrix diffusion under solubility-limited boundary conditions of a target radionuclide for the band-type release. Numerical inversion of the Laplace transform method is applied to estimate concentrations in a fracture and a finite rock matrix and fluxes at the fracture surface. Matrix diffusion into a finite rock matrix shows enhanced radionuclide migration and a higher concentration profile in a fracture. Diffusive flux from a finite rock matrix into a fracture after the end of leaching time shows higher peak values than flux from an infinite rock matrix because of (a) higher saturation of a radionuclide in a finite rock matrix and (b) increase of a radionuclide concentration in a fracture. Therefore, it is more realistic and conservative to apply the finite matrix diffusion for the overall assessment in a potential repository embedded in a fractured porous medium.
