Determining the Water Retention Curve (WRC) is a key factor in properly solving
unsaturated flow through a material. Commonly, its characterization is obtained by means of laboratory tests, but these methods are quite challenging due to time and resource constraints.
Alternatively, estimations based on material index properties can be made; however, this approach does not always produce results that fit well with the data obtained from laboratory tests.
The aim of the current study is to evaluate the impact of each adjustment parameter used to characterize the WRC of a material on unsaturated flow problems. This was carried out through a global sensitivity analysis of 1D flow models, considering representative materials from Chilean mine tailings, whose unsaturated behavior is modeled using the equation proposed by van Genuchten (1980).
In summary, three different types of tailings from various mining operations in Chile were considered, and for each case, 2000 simulations were run following a Monte Carlo scheme. Each run represents a different combination of parameters
that define a specific WRC for the material. Likewise, the hydrological conditions used in the numerical simulations were adapted to the typical environmental conditions of Northern Chile.
The results of the sensitivity analysis conducted in this study aim to improve and strengthen the numerical work performed through 1D models, providing a deeper understanding of how the adjustment parameters of the water retention curve affect the unsaturated behavior of Chilean mine tailings and, consequently, how these changes influence the flow results obtained through unsaturated modeling performed for this kind of material.
