I am trying to find a way to import ALOHA's plume model (.PAS) into QGIS? I have not been able to find anything showing how to accomplish this outside of using ESRI-based tools.
I don't think .PAS files can be imported directly but according to the description I found (http://www.gis.smumn.edu/gradprojects/jakalas.pdf) it's just a pretty simple text format with x and y coordinates. Seems like an offset has to be added to these x and y coordinates but that's it. Should be possible to handle even in a spreadsheet software (like Calc or Excel). Add the offset and export a CSV. That can be imported into QGIS.
If your .PAS file is different from the one shown in the PDF, you might want to post a sample.