There are several TOUGH-based THM codes, with different capabilities and at different stages of development and release. For a very brief overview, see Section 4.4 of the review article at http://dx.doi.org/10.1016/j.cageo.2013.06.009.
Consider contacting Jonny Rutqvist (JRutqvist@lbl.gov) who is involved in most THM-related efforts, or check the publications at http://esd.lbl.gov/research/projects/tough/documentation/publications.html, choosing TOUGH-FLAC as the module.
First of all, I would like to thank you because of your time and attention. I was wondering if you could provide me some more information about the Tough-Flack. I appreciate it if you could tell me how it is possible for me to obtain more information about the application of Tough-Flack and the way I can use it. I have read the Manual of Tough2 and I found out I should write the code in FORTRAN for my model and then implement it in Tough2. I was wondering if it is the same for Tough-Flack too.
I'm not sure I understand your question or what exactly you want to do (i.e., get general information about TOUGH-FLAC, learn how to run an application, develop your own THM code based on TOUGH2, implement a specific "model", ...?). I suggest we take this discussion off the Forum; Jonny would be the person to contact with all TOUGH-FLAC related questions; I'd be happy to address other issues (SAFinsterle@lbl.gov).