Geochemical Modeling with ORCHESTRA
This two-day course will teach the participants to set up geochemical modelling cases using the software-package ORCHESTRA. Special attention will be given to modelling using advanced adsorption models i.e. the NICA-Donnan for metal binding to organic matter; the Generalized Two Layer Model for ion binding to (hydrous) oxides (Al,Fe,Mn) and the CD-MUSIC model for ion binding to (hydrous) ferric oxide. The optimisation of model parameters using ORCHESTRA in combination with PEST will be demonstrated with a case to optimise proton and metal binding parameters for the NICA-Donnan model based on experimental data. We will discuss the multi-surface approach to model metal partitioning and speciation in soils, sediments and surface water systems and the possibility to combine this with reactive transport modelling. The course includes introductions to the topics and practical sessions to work with the model.