The GoldSim Contaminant Transport Module Online Course is Now Available!

Posted by Rick Kossik

Over the last two years I posted six excerpts from the Contaminant Transport Module Online Course. I had promised that it was under development and would eventually be posted in full. I posted the last of these excerpts a year ago and then went silent, so you may have wondered "what happened?". With the exception of the last excerpt, these were from the (early) conceptual parts of the Course. The remainder of the Course is "hands-on" and procedural and would not have necessarily worked well in a blog format. Hence, the silence. Well, FINALLY (after 2 years of effort) the full Course is now available. In this post, I briefly provide an overview of what you can expect.

Avoiding Concentration Spikes when Simulating Cells that are Emptying (and Refilling)

 Posted by Rick Kossik

As part of the process of creating a very detailed online course for the GoldSim Contaminant Transport Module (for which a number of excerpts have been published in previous blog posts), I have been revisiting the most common questions and problems that we have been asked about by our users over the years in order to make sure to discuss these in the course (as well as to add more detailed descriptions, when warranted, in the User's Guide).

One of the more common issues that we see is the problem of GoldSim producing unrealistic spikes in computed concentrations when the volume of water (or another medium) in a Cell changes significantly over a timestep.  This most commonly happens when the Cell dries out (i.e., the volume actually goes to zero) and (perhaps) subsequently refills. There is a way to avoid this problem (which we have provided to users when the issue arises), but it is not discussed in detail in the current version of the User's Guide (which will be remedied in the next release).

In this blog post, I will first discuss the nature of the problem (when does it occur?) and how to address it in the current release of GoldSim (12.1).  For those that are interested, I will then discuss the numerical reasons for this problem, as well as an alternative approach that will be available for addressing the problem in the next GoldSim release (expected later this year).

GoldSim Contaminant Transport Module Online Course, Excerpt #5: Chemical Processes Controlling Mass Transport

Posted by Rick Kossik

This is the fifth installment of short excerpts from the online CT Course that is currently under development. These excerpts are all, by necessity, from the conceptual parts of the Course, as those parts that are "hands-on" don't necessarily work well in a blog format.  However, there is plenty of conceptual matter to discuss (the Course is very detailed and extensive), so I'm hoping you will still find these excerpts useful. 

The first excerpt simply provided the outline describing how the Course will be organized.  The second excerpt  discussed the key decisions required before starting to build a contaminant transport model. The third excerpt discussed the problem of uncertainty in contaminant transport models and the underlying philosophy of the GoldSim Contaminant Transport Module. The fourth excerpt provided an overview of the physical processes controlling mass transport (advection, dispersion and diffusion).

This excerpt provides an overview of the chemical processes controlling fate and transport.

GoldSim Contaminant Transport Module Online Course, Excerpt #4: Physical Processes Controlling Mass Transport

Posted by Rick Kossik

As I noted in previous blog posts, I am currently working on an online CT Course. In order to provide some useful material for users in the meantime, I plan to post excerpts from time to time as I slowly progress through the development of the Course.  

The first excerpt simply provided the outline describing how the Course will be organized.  The second excerpt  discussed the key decisions required before starting to build a contaminant transport model. The third excerpt discussed the problem of uncertainty in contaminant transport models and the underlying philosophy of the GoldSim Contaminant Transport Module. 

This excerpt finally starts to get a bit more technical, and provides an overview of the physical processes controlling mass transport (advection, dispersion and diffusion).

GoldSim Contaminant Transport Module Online Course, Excerpt #3: The GoldSim Contaminant Transport Modeling Philosophy

 Posted by Rick Kossik

As I noted in previous blog posts, I am currently working on an online CT Course. In order to provide some useful material for users in the meantime, I plan to post excerpts from time to time as I slowly progress through the development of the Course.  

The first excerpt simply provided the outline describing how the Course will be organized.  The second excerpt  discussed the key decisions required before starting to build a contaminant transport model. In this excerpt from one of the introductory Units of the Course, I discuss the problem of uncertainty in contaminant transport models and then summarize the underlying philosophy of the GoldSim Contaminant Transport Module.

GoldSim Contaminant Transport Module Online Course, Excerpt #2: Key Decisions Required Before Starting to Build a Contaminant Transport Model

 Posted by Rick Kossik

As I noted in my previous blog post, I am currently working on an online CT Course. This will be a long-term project (I'm hoping to finish by the end of the year).  But in order to provide some useful material for users in the meantime, I plan to post excerpts from time to time as I slowly progress through the development of the Course.  A blog is not the best venue for presenting the entire Course (even in parts), but I think it will be possible to provide a number of short excerpts that could be of value.

The first excerpt simply provided the outline describing how the Course will be organized.  In this excerpt, I present some information from a preliminary Lesson discussing the key decisions required before starting to build a contaminant transport model.