Abstract. Two-phase characteristic curves are necessary for the simulation of water and vapor flow in porous media. Existing functions such as van Genuchten [1980], Brooks and Corey [1966], and Luckher et al. [1989] have significant limitations in the dry region as the liquid saturation goes to zero. This region, which is important in a number of applications, including liquid and vapor flow and vapor-solid sorption, has been the subject of a number of previous investigations. Most previous studies extended standard capillary pressure curves into the adsorption region to zero water content and required a refitting of the revised curves to the data. In contrast, the present method provides for a simple extension of existing capillary pressure curves without the need to refit the experimental data. Therefore previous curve fits can be used, and the transition between the existing fit and the relationship in the adsorption region is easily calculated. The data-model comparison shows good agreement. This extension is a simple and convenient way to extend existing curves to the dry region. Common ad hoc fixes used in numerical simulations to circumvent these limitations include (1) specifying the residual saturation for capillary pressure lower than that for relative permeability, (2) linearization of the capillary pressure curve at an arbitrary liquid saturation slightly greater than the residual value, such that the slope of the capillary pressure curve is always finite, and (3) specifying a maximum capillary pressure. While the modifications allow numerical simulations to proceed, they are arbitrary, and a better and more meaningful modification is needed.

The FEBEX (Full-scale Engineered Barriers Experiment in Crystalline Host Rock) ''in situ'' test was installed at the Grimsel Test Site underground laboratory (Switzerland) and is a near-to-real scale simulation of the Spanish reference concept of deep geological storage in crystalline host rock. A modelling exercise, aimed at predicting field behaviour, was divided in three parts. In Part A, predictions for both the total water inflow to the tunnel as well as the water pressure changes induced by the boring of the tunnel were required. In Part B, predictions for local field variables, such as temperature, relative humidity, stresses and displacements at selected points in the bentonite barrier, and global variables, such as the total input power to the heaters were required. In Part C, predictions for temperature, stresses, water pressures and displacements in selected points of the host rock were required. Ten Modelling Teams from Europe, North America and Japan were involved in the analysis of the test. Differences among approaches may be found in the constitutive models used, in the simplifications made to the balance equations and in the geometric symmetries considered. Several aspects are addressed in the paper: the basic THM physical phenomena which dominate the test response are ARTICLE IN PRESS www.elsevier.com/locate/ijrmms 1365-1609/$ -see front matter r

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Since 2013, Xylella fastidiosa Wells et al. has been reported to infect several hosts and to be present in different areas of Europe. The main damage has been inflicted on the olive orchards of southern Apulia (Italy), where a severe disease associated with X. fastidiosa subspecies pauca strain De Donno has led to the death of millions of trees. This dramatic and continuously evolving situation has led to European and national (Italian and Spanish) measures being implemented to reduce the spread of the pathogen and the associated olive quick decline syndrome (OQDS). Research has been also carried out to find solutions to better and directly fight the bacterium and its main insect vector, Philaenus spumarius L. In the course of this frantic effort, several treatments based on chemical or biological substances have been tested, in addition to plant breeding techniques and integrated pest management approaches. This review aims to summarize the attempts made so far and describe the prospects for better management of this serious threat, which poses alarming questions for the future of olive cultivation in the Mediterranean basin and beyond.

The goal of the DARPA "Dog's Nose" program is to develop a sensor capable of detecting explosives contained in all buried landmines. In support of the DARPA program, the purpose of the Explosives Fate and Transport (EF&T) experiments is to define in detail the accessible trace chemical signature produced by the explosives contained in buried landmines. We intend to determine the partitioning (soil, air, water), composition, and quantity of explosive related chemicals (ERC) which emanate from different kinds of landmines (predominantly plastic-cased with TNT as the main charge) buried in multiple soil types and exposed to various climatic events. We are also developing a computer model that will enable us to predict the composition and quantity of ERC under a much wider range of environmental conditions than we are able to test experimentally.In our systematic quest to define the signature of a buried mine we have divided our efforts into the following categories:1 . Chemical analysis of the main explosive charge from several sources of TNT and the equilibrium vapor associated with TNT from these sources. 2. The amount and composition of ERC that are found on the exterior of landmines. 3. Determination of the rate at which ERC permeate the casing materials of both plastic and metallic landmines. 4. The effect that different soils have on the transport and fate of ERC as they move through the soil/pore matrix to the surface.5. The effect of environmental factors on ERC, i.e., climate, time since burial, depth of burial, soil properties, sunlight, near surface air movement, and vegetation.