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Newton-Raphson did not converge after 999 iterations


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I continually get this error after importing groundwater data I have for a sampling into the basis.  I originally started with some uncoupled compound that I had data for in soil and water, but was getting error, so I tried to simplify, couple and only add the 1 compound.  I tried balancing to Cl- in hopes that might help.  Nothing has thus far. Wasting a lot of time. Help would be most welcome.

121S React File-All Compounds.rea

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Hello bclement2142,

I took a look at your input file and noticed a couple of things. React begins a simulation by calculating the speciation of the initial fluid and bringing it to equilibrium. Unless otherwise specified, the default setting in React swaps in a number of necessary mineral phases to allow the solution to precipitate minor mineral mass and come to equilibrium. When I ran the input file as is, I got the error message of convergence issue and also that the initial solution is too supersaturated. The results pane for the run shows that there are 21 minerals that are supersaturated. You can try to use the suppress function to suppress the minerals that you don't expect to precipitate in your system. Just as a test, I suppressed all the minerals in the system and the React script ran with no problems. However, I am not sure of the origin of your water and the conceptual model of your work, so the minerals selected for suppressing should be considered carefully. You can try using Spec8 to figure mineral saturation of your initial solution. You can then iteratively suppress saturated minerals in your React input file that might not be likely forming in your system. For more information regarding the the suppress feature, please refer to the GWB Command Reference guide. 
Hope this helps,
Jia Wang
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