Loic

Dear colleagues,

I am looking for experiences or exemples of Feflow models of an unsaturated waste dump (in a copper mine) in low recharge environment.  I would like to assess the feasability of doing the work in Feflow as we normally use SeepW 2D sections.

In my actual problem, the main flow directions seem complex and suggest the need of 3D modelling as the dump lays in a valley with 2 quebradas underneath.
I would be grateful if you could provide me with feedback from your experiences and the main difficulties encountered (although I understand some of them may be very specific to your project ...).

Particularly, the dump is composed of  very variable materials and I wonder how complicated the structure/layering can be and then how complex the unsaturated flow modeling can become.

Thanks for your feedback

Loic   

Thanks Peter, the demo is very useful. The User defined menu seems to offer a certain degree of flexibility how to represent recharge and/or evapotranspiration.
Best regards

Loic

Dear Feflowers,

I am working on a model in the Atacama desert and I would need to implement an evaporation function from the water table for specific humid zones in the area (salars).  Is there an embedded function/method to apply this type of concept in Feflow (by analogy I am thinking about the EVT or ETS package in Modflow) or is it necessary to develop a piece of code (or integrate an existing piece of code) ?
Thanks to share your experience about this and best regards.

Loic RAGAS

Dear Modellers,

I have problems with my model in steady state as heads remain well above topography in spite of the seepage nodes in slice 1, with topographic elevations.
When looking at the budget, it appears that the seepage nodes do not drain any water, and I do not understand why.
Is there a way to activate seepage nodes in steady state or are they just for transient mode ? Thanks.
Best regards

Loic

I have tried your suggestion but the problem is that recharge (fresh water) is occuring on the whole model and so after a while the initial concentration goes below the background concentration by dilution.
If I put some fixed background concentration BC everywhere (but the contaminant sources), I won t be able to observe my plume distribution ????

I am trying to model the leakage of a tailings storage deposit facility in a valley using chloride as transport specie. The problem I have is that I can not find an (easy) way to force the minimum cloride concentration to 200mg/l at all stress periods and everywhere as it is considered as the background concentration in this area.
Would you have any suggestion how to address this issue ?

Loic

I suppose your seepage nodes are set up in slice 1. Is it possible that the piezometric water level in slice 2 is higher than the bottom of the excavation ? In this case you may have to put BC in slice 2 too (?) to achieve a complete dewatering ...

Laurent,
you can use the 1st Dirichlet boundary condition as seepage node. Basically you have to check that the max. constraint value is null for each BC so that you have seepage nodes and not constante heads.
Good luck

Loic 

Hi there,

I am trying to have Feflow running in batch as shown in the example but unfortunately the script does not go until the end and basically 2 out of the 3 scenarii only can be completed.
The DOS window shows that the program is not finished (Feflow process is still active) and the 3rd .dac is not created. Furthermore there is none error message. For info, I am using Feflow 5.405 and Windows XP.
If you have experimented this kind of problem, I would be grateful to know how you managed to address it as using the batch mode is quite useful for multiple runs with only 1 license.
Thanks and best regards.
Loic

Since I have moved from version 5.309 to 5.405, I have noticed that whatever the text you input in EDIT / EDIT PB ATTRIBUTES / PB CLASS / TITLE and save + close the fem, this text is not saved and so, when you re-open the same fem file afterwards, you still have the default string "A new Feflow problem", which I think is a bug of version 5.405 (as this was ok in 5.309).

Loic