Hi,
Sure, the easiest way would be to make a spreadsheet with one column of all the extensions you want to remove. Then copy all the cells from there. Open DSA and select the advanced tab on the left and click on import. In the import window select station as the object and remove as the action. This should open a small "spreadsheet" with just the extensions visible - paste the data from the spreadsheet in here. CLICK THE DISK ICON TO SAVE THIS OR IT WON'T WORK. Then click on the lightning icon to run the remove. In the status window at the bottom, click on the history tab (?) to see the progress - x successfull and x failed.
Hope this helps,
Chris