Documentation of the Thermal Energy Balance Equation used in the USNT Model of the NUFT Flow and Transport Code

Delayed signatures of underground nuclear explosions

“…The coupled physical and radiochemical processes are modeled using the USNT module of the NUFT simulator 10 11 developed at Lawrence Livermore National Laboratory. The models are developed in a two-dimensional, radial-symmetric domain extending vertically from the ground surface to the water table and radially from the vertical axis passing through the detonation point to the outer boundary at a significant distance where the assumption of the ambient thermal and concentration condition is justified.…”

“…Our field experiment deals only with the transport of a surrogate chemical tracer rather than an evolving suite of parent/daughter radionuclides having different migration characteristics in the subsurface. Using the hydrogeologic characterization of the Pahute Mesa site obtained from the field experiment in a two-phase convection model with barometric pumping, we developed computer simulations using the NUFT 10 11 simulator that take into account both the production of radioxenon daughter products from their radionuclide parents 17 within the post-detonation chimney as well as the effect of differential migration associated with high-mobility noble gas daughters and the low-mobility chemically reactive iodine parent. Evolution of the full isotopic makeup of a noble gas signature was evaluated at several locations within the containment regime using a radionuclide decay-chain/network computational model for simultaneously tracking 22-isotope parent/daughter radionuclides in the presence of subsurface transport processes 12 .…”

A three-electrode column for Pd-catalytic oxidation of TCE in groundwater with automatic pH-regulation and resistance to reduced sulfur compound foiling

“…NUFT (Nonisothermal Unsaturated-saturated Flow and Transport), a code developed at Lawrence Livermore National Laboratory (Hao et al, 2011; Nitao, 1998), was used to perform numerical simulations of TCE reactive transport. NUFT has been demonstrated as a robust and accurate model in many applications for simulating mass transfer and reactive transport (Buscheck et al, 2012; Sun et al, 2000).…”

Underground Test Area Fiscal Year 2014 Annual Quality Assurance Report Nevada National Security Site, Nevada, Revision 0

“…Crater recharge information French (1998, 2000); Hokett and Gillespie (1996) Unclassified published data descriptive of detonation histories and releases of radiological effluents Schoengold et al (1996) Various monographs and technical reports describing the underlying basis for hydrothermal fluid flow and mass transport phenomena in porous and fractured rock and the numerical simulations of these processes using the NUFT code Bird et al (1962); Keenan et al (1969); Bear (1979);van Genuchten (1980); Pollock (1986); Gerke and van Genuchten (1993); Holman (1990); Manteufel et al (1993);Zimmerman et al (1993); Nitao and Bear (1996); Ho (1997); Liu et al (1998); Nitao (1998Nitao ( , 2000; Neuman and Wierenga (2003); SNL (2007); Troldborg et al (2007); Sun et al (2008) Open literature…”