Representation of two-phase flow in the vicinity of the repository in the 1996 performance assessment for the Waste Isolation Pilot Plant

The following topics related to the representation of two-phase (i.e. gas a nd brine) flow in the vicinity of the repository in the 1996 performance as sessment (PA) for the Waste Isolation Pilot Plant (WIPP) are discussed: (i) system of nonlinear partial differential equations used to model two-phase flow: (ii) incorporation of repository shafts into model; (iii) creep clos ure of repository; (iv) interbed fracturing; (v) gas generation; (vi) capil lary action in waste; (vii) borehole model; (viii) numerical solution; and (ix) gas and brine Row across specified boundaries, Two-phase flow calculat ions are a central part of the 1996 WIPP PA and supply results that are sub sequently used in the calculation of releases to the surface at the time of a drilling intrusion (i.e. spallings, direct brine releases) and long-term releases due to radionuclide transport by flowing groundwater. Published b y Elsevier Science Ltd.