Published online by Cambridge University Press: 25 February 2011
Adequate representation of fracture-matrix interaction during episodic infiltration events is crucial in making valid hydrological predictions of repository performance at Yucca Mountain. Approximations have been applied to represent fracture-matrix flow interaction, including the Equivalent Continuum Model, which assumes capillary equilibrium between fractures and matrix, and the Fracture-Matrix Model, which accounts for nonequilibrium fracture-matrix flow. We analyze the impact of matrix imbibition on episodic nonequilibrium fracture-matrix flow and transport for the eight major hydrostratigraphic units in the unsaturated zone at Yucca Mountain.