Not sure when it was added as I don't do archaeology much if at all but they have added a dig site progress bar to the game.
At present it isn't movable in nUI but with the following change it will be.
In nUI\Plugins\nUI_Movers.lua find the section starting nUI_Movers.managedFrames = and notice that there is a table just above it ..
Add the following just inside in the closing brace so it is the last frame that is movable using the left mousebutton.
Lua Code:
{
frameName = "ArcheologyDigsiteProgressBar",
addOn = "Blizzard_ArchaeologyUI",
parentName = nil
},
The screenshot shows the movability option now in place and in the same place where blizzard puts it currently.