Simulating Infiltration at the Large-Scale Ponded Infiltration Test, INEEL

[摘要] This work involved using ITOUGH2 to simulate the Large-Scale Ponded Infiltration Test (LPIT) at Idaho National Engineering and Environmental Laboratory (INEEL) in order to calibrate parameters controlling the infiltration of water in fractured basalt using a dual-permeability modeling approach. This supports the higher objective of building confidence in the use of the dual-permeability approach for modeling flow and transport in unsaturated fractured rock systems. In particular, the objective of this work is to be able to understand transport of radionuclides at INEEL and subsequently at Yucca Mountain, Nevada. A 3-D dual-permeability mesh representing the geological conditions at the LPIT was constructed as shown by the cross-section on Figure 1a. The geology consisted of surficial sediments, two separate basalt flows (A and B basalts) underlain by a low permeability sedimentary interbed (BC interbed), with a lower C basalt constituting the bottom of the model. Water was allowed to infiltrate from the pond and then pool on top of the sedimentary interbed. Water pressure and {sup 75}Se breakthroughs were simulated at four wells screened within the fractured basalt on top of the sedimentary interbed (B04N11, C04C11, B06N11, C06C11) along two radial angles and at two radial distances. Model results were calibrated to field data using ITOUGH2.

[发布日期] 2001-05-31 [发布机构] United States. Department of Energy. Yucca Mountain Project Office.

[关键词] Ponds;Sediments;Geology;Basalt;Simulation