Hi,
I'm a new user to the software and am trying to simulate reduction of hexavalent chromium to chromium III by reacting the defined system with a ferrous sulfate amendment. As the ferrous sulfate concentration is increased in the reactants pane, more and more hematite is precipitated but very little to no chromium is converted from Cr VI to CrIII. Am I missing a step, or is this just what is most likely to happen under these conditions? I noticed also that Eh hardly seems to change from iteration 0 to 100 when the solution converged, no matter what concentration of the amendment is used. Is there a way to add your field measured Eh data in the Basis pane? Or can you only add it on a sliding scale in the Reactant pane? When I adjust the Eh in the reactants pane, the chromium does seem to precipitate out in the simulation, but it seems arbitrary for me to manually alter the Eh - I want to make sure that's what would be occurring in the real system as a result of the amendment. Does GWB automatically account for Eh changes as the result of a reactant with the system or does that need to be added as it's own reactant? I've attached the txt file script for the solution and the .rea file.
Thanks,
Ben
React_output-React 25 mgL Ferrous Sulfate.txt
MW-5S React_1-123016.rea