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Rich Carbonaro

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  1. As a feature request, adding the new kinetic reaction options in the MT3D-USGS RCT package. The MT3D-USGS manual discusses: 1. Instantaneous reactions between one electron donor and one electron acceptor, 2. Monod kinetics, 3. Sequential first-order reactions, 4. Kinetic reaction between multiple electron donors and acceptors As always, thanks for monitoring these forums.
  2. Has anyone on this forum seen this error from MT3D? "error: a or b too big, or MAXIT too small in betacf" It happened to me 6 hours into an 8 hour model run. I have tracked this down to a function call to the pearsn subroutine which it turn calls betacf in the Transport Observation Package. The purpose of the function is to calculates statistics on the goodness of fit between model and observed concentrations. It appears to have nothing to with actual solute transport calculations. What triggered the error was a slight change to my specified concentration cells. Maybe MAXIT in the source code needs to be increased? Default value is 100 but I'm not sure if this would do the trick. Rich
  3. A question on GMS coverages for MT3D: Can a coverage be created for parameters in the MT3D Chemical Reaction Package? For example, I would like to set up zones within a model with different sorption coefficients and first-order reaction constants. It does not seem like these options are available when setting up a coverage - am I missing something? Or, is this only something that can be done in Grid Mode. Thanks, Rich
  4. I second this suggestion. I've started working with MT3D-USGS by using GMS to create some of the necessary input files and then running MT3D-USGS from the command line. It would be great to have this new version of MT3D implemented in GMS.
  5. Alan, Thanks for the update. I have a feeling this package isn't being used by that many GMS users, especially since GMS can do some of what TOBS can do through the concentration observation coverage. Also, thanks for your help with the TOBS elapsed time issue. It was much appreciated! - Rich
  6. Alan - Has there been any consideration given to adding the above features? I'm not sure how folks are doing solute transport calibration without use of the TOBS package and the output it provides. These would be two very helpful enhancements. - Rich
  7. Alan, I have done some testing of MNW1 and MNW2 with MT3D within the GMS environment and wanted to follow-up on this issue. As of version 1.0.5, MODFLOW-NWT writes the MNW2 fluxes to the flow transport link file. The release notes are here: http://water.usgs.gov/ogw/modflow-nwt/release.txt Through testing in GMS v 10.0, I was able to produce reasonable results for solute transport using MODFLOW-NWT/MT3D and the MNW2 package. Solute passes through non-pumping MNW2 wells from high head to low head (as it should). I specified a source of solute as ITYPE = 27 in the source sink mixing package (same ITYPE as MNW1) and was able to inject solute through an MNW2 well. Mass balance errors were small (as long as you specify a reasonable DT0 value) leading me to believe that you can do transport modeling while using the MNW2 package as long as you are using MODFLOW-NWT version 1.0.5 or later (which GMS does use). Please let me know your thoughts on this - I'd like to have confirmation that this works from the experts. Thanks, Rich
  8. One additional item that would really improve how TOBS works in GMS: Add the well id to the comment lines in the header of the TOBS input file. For example, the input of *.tob files is shown below. The POINT 1 refers to the first monitoring well in the coverage and "conc0" is assigned as the name (presumably so as not to have any invalid characters or spaces). # TOBS package input file (GMS - 6.0)#GMSCOMMENT 1bef6b22-ea40-4722-8952-20a675a4cc41 POINT 1 280.0 615.0 conc0#GMSCOMMENT 1bef6b22-ea40-4722-8952-20a675a4cc41 POINT 1 280.0 615.0 obs1#GMSCOMMENT 1bef6b22-ea40-4722-8952-20a675a4cc41 POINT 1 280.0 615.0 obs2
  9. Sure thing. I'll post it now with my last name in the name of the zip file.
  10. Thanks Alan - that helps a lot. I became interested in using TOBS because it has the capability of calculating a "blended" concentration when you have a monitoring well screened across multiple model layers. But, I don't think GMS is writing the *.tob file correctly. If I create a concentration observation coverage using "by well screen" and map it to MT3D, the resulting TOB file does not have the correct proportions from each layer. This is controlled by variable prLayer(i) according to the MT3DMS v5.3 manual, and this variable must sum to 1 for each monitoring well. An example of the TOBS file written by GMS for my model is below (prLayer(i) is in bold-red text): conc21 -2 40 28 1 -1.0 -0.500000 0.500000 -1.0 0.01 1.000000 1 1.000000 conc22 -3 39 29 1 -1.0 0.000000 0.000000 -1.0 0.01 1.000000 1 1.000000 2 0.000000 conc23 -4 40 29 1 -1.0 -0.500000 0.500000 -1.0 0.01 1.000000 1 1.000000 2 0.000000 1 0.600000 Notice for conc21, that it sums to 2.0. When I check the coverage for this monitoring well the concentration is about 2-times what it should be. Similar for conc22 and conc23. Something seems off with the algorithm for calculating prLayer(i).
  11. I'm using the Transport Observation Package (TOBS) with MT3DMS in a simple GMS model (v10.0.10) for testing purposes. I noticed that when the Transport Observation Package is active, calculated concentrations at observation locations are not being interpolated from its neighboring nodal points. This is in contrast to how GMS reports concentrations when the TOBS package is not activated. I checked the TOBS input file (*.tob) and noticed that the iConcINTP flag which controls how TOBS handles interpolation is set by GMS to zero (no interpolation). The benefit of the TOBS package is that it calculates mass fluxes at groups of source/sink boundary conditions. I do not believe that GMS can do this in post-processing without the TOBS package active. Based on the above, I have two questions: 1) Is there any way to tell GMS to turn on the interpolation in TOBS on so that interpolation is performed? I was able to turn it on manually by saving in GMS, opening the TOBS file and changing the iConcINTP from 0 to 1. 2) I'm wondering if interpolation "on" (iConcINTP = 1) should be the default option in GMS since the output would be more consistent with how GMS does post-processing on concentrations at observation points. Any insight on this would be appreciated. - Rich Carbonaro
  12. I have a question related to the use of the Multi-Node well packages (either MNW or MNW2) within a transport simulation. With the well package (WEL), you can set up a coverage and specify the concentration of each species in the water you are injecting into the model. This approach is extremely useful and works really well as long as your conceptual model matches up with the simulation settings (i.e. RT3D, MT3DMS, etc.). With coverages for the MNW packages, it does not appear that you are given the option to specify these concentrations. I was experimenting with a work around where you set up a polygon coverage of starting concentrations within the cell with the multi-node well. This approach is a bit cumbersome but appears to work. My question is a bit open-ended but is there a way to specify the concentration in the injected water in the conceptual model for a multi-node well? If the answer is "no", is there a procedure for doing this properly in the grid approach? As always, thanks for your response! - Rich Carbonaro
  13. When switching back and forth between results from MODFLOW and MT3D/RT3D, I am constantly re-entering different contour settings (no of contours, min, max, contour interval, type of contours - line or color). Having the ability to save these contour settings and then call upon them in a drop down box would be a great addition to the post-processing abilities of GMS. Thanks, Rich C.
  14. Bill - Thanks. Make sense - works well. - Rich
  15. Is there a way to contour starting concentrations for a MT3D/RT3D/PHT3D model? If not, this would be a helpful feature to check that coverages are being mapped as intended. - Rich
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