Tracking Br- movement through the vadose zone by taking undisturbed core samples and using ion chromatographic techniques based on soil-water extracts is difficult and time consuming. Moreover, the presence of Cl- in the soil may hamper Br- detection due to interference between the two ions. The aim of this investigation was to check whether x-ray fluorescence is an appropriate method for measuring Br concentration in soil samples. A field study was performed comparing Br- chemical analysis in soil-water extracts to total Br in soil using an x-ray fluorescence method. Our results showed a statistically significant functional relationship between the measured concentrations using the two methods. Total Br quantification by x-ray fluorescence was shown to predict the total Br concentration in soil samples with minimum sample preparation (approximately 15 min) and thus the concentration within the vadose zone.
An experimental system to perform hydromechanical tests on a column of porous material under different environmental and boundary conditions was designed and constructed. The system allows different porous materials (natural or anthropogenic soil, mine waste, and resins) to be studied under variably saturated conditions. The automatic system has three main components: the physical apparatus itself, an electronic interface, and an automatic data logging and control unit. Experimental results obtained on metallurgical waste (MW) demonstrate that the system is capable of accurately measuring soil suction, changes of water content, temperature, and relative humidity at different points in the sample, as well as vertical shrinkage and evaporation. Performance of the system was found to be excellent because it allows increases or reductions in the sample size and changes in various parameters and variables according to the purpose of the tests. The system was used to study flow under saturated and unsaturated conditions, using metallurgical waste from the Cuban nickel industry. Results show the influence of hydromechanical processes on the soil hydraulic properties and flow in porous media.