Lesson 10 – Becoming an Expert GoldSim Contaminant Transport Modeler

Congratulations! You’ve almost completed the GoldSim Contaminant Transport Module Course.  As we noted in the first Unit, the purpose of this Course was to teach you the fundamental concepts associated with contaminant transport modeling using GoldSim. And if you took the time to work through the Examples and Exercises, we should have accomplished that.

Note, however, that you cannot become an expert (or even a proficient) GoldSim contaminant transport modeler simply by completing a Course such as this.  You should, however, now have all the tools necessary to become a proficient modeler.  Becoming a proficient (and eventually, an expert) modeler, of course, will take practice.

Building realistic and useful contaminant transport models requires four things:

1. An understanding of fundamental contaminant transport concepts (e.g., advection, dispersion, diffusion, sorption);
2. An understanding of the use of one or more tools (e.g., GoldSim) that you can use to build a model;
3. A conceptual and quantitative understanding of the specific system you are trying to model; and
4. The ability to evaluate a system, conceptualize it in a generalized (and often abstract) way, and subsequently represent the features, processes and events defining the system quantitatively at an appropriate level of detail.

This Course has focused primarily on the second item (although we did provide some discussion with regard to the first). The third item is obvious. If you want to model a system, you must first have a conceptual and quantitative understanding that of that system. It should be noted, however, that this does not mean you need to be an expert on all of the details of that system.  In fact, for many complex systems, no one person will be an expert on all aspects of the system, as the model may involve sub-systems that require a wide range of expertise. The best modelers, however, are able to ask the right questions, obtain information from subject matter experts, and integrate this information into a cohesive and representative model.  This, in fact, leads into the fourth item.

Whereas the first two items are things you can obtain through study and practice (e.g., reading textbooks, taking a Course and using a tool), and the third item is something you can obtain largely through access to subject matter experts (or perhaps technical literature), the fourth item, unfortunately, is something that for the most part cannot be easily learned from a book.

The fourth item (which is arguably the most difficult skill to acquire) is not specific to the Contaminant Transport Module.  This ability is required to use GoldSim (or any simulation tool) for any kind of application.  The ability to evaluate a system and subsequently integrate and represent the features, processes and events defining the system in an appropriate way into a quantitative model takes trial and error, practice and experience, and perhaps most importantly, interaction with and feedback from experienced modelers. How detailed should the model be?  Which processes can be ignored and which need to be included? How can a particular process be represented in a generalized and robust way?  These are the kinds of questions that will need to be addressed when building a model, and the questions and answers will be different for each model. Learning how to answer these questions requires practice and experience, and the more experience you have, the better you will be at it.

When answering these questions and building a model, you are encouraged to keep in mind what George Box told us at the beginning of this Unit: “Remember that all models are wrong; the practical question is how wrong do they have to be to not be useful.”

Before closing, it is worthwhile to remind you of the resources available to continue to improve your modeling skills.

The best way to learn how to build realistic models is to actually examine some.  If you have other, more experienced GoldSim users in your organization, you should certainly explore and study their models.  If this is not possible, however, another excellent resource you can take advantage of is the GoldSim Model Library.  The Model Library contains a collection of example models that allow you to see how specific features of GoldSim can be used and/or how GoldSim can be used for specific applications. Although most of the models are small, some are quite large, and almost all of them are more complex than the simple Examples and Exercises we’ve worked on in this Course.  As a result, an excellent way to continue to learn about building models in GoldSim is to visit and explore the Model Library, and you are strongly encouraged to do so.

In addition to the Model Library, there are also other resources for you to take advantage of:

• Visit the GoldSim Forum.  The Forum provides an opportunity for you to post questions to the GoldSim community, or just browse existing entries.
• Sign up for GoldSim webinars. The free monthly webinars demonstrate GoldSim features and capabilities.  All webinars are archived, so if you cannot attend the live webinar, you can still view it online at any time.
• Follow the GoldSim Blog, which provides an informal mechanism for GoldSim staff to share their knowledge, point out some of the more advanced (and perhaps overlooked) GoldSim features, share and discuss common mistakes we see in GoldSim applications, discuss interesting applications, and keep you abreast of our plans for further GoldSim developments.
• Join the GoldSim LinkedIn Group, where we post important announcements (e.g., new versions, interesting applications), and you can interact with other users.
• Request on-site or remote training.  We can provide on-site training to follow-up on the material you learned in this Course.
• Get help with specific applications from GoldSim consultants.

Finally, when you purchase GoldSim, you are entitled to one year of free support (GoldSim Help Center), and this can be extended every year through the GoldSim Maintenance Program. This does not include assistance in building and debugging your models, but it does include answering questions on how to use GoldSim’s features, so do not hesitate to contact us. You can also purchase blocks of advanced support.

Good luck and we hope you enjoy using the GoldSim Contaminant Transport Module!