No having to back the machine up, no need to send a crew in a tight space, quick sample obtained.
All manner of oilfield exploration type tools could be sent through a 6" access hole, just like in a well.
I don't know for a fact that the cutter head isn't designed with such a feature already. I've only done a bit of light reading on this machine in the last few days.
Who knows? Maybe the reporters don't know what the hell they're talking about. I'd say that's a virtual certainty, given what we know of today's media. Bertha is as sophisticated as anything we fly in space. I doubt the engineers would have forgotten something so basic to the design.
http://www.seattlemag.com/gallery/closer-look-bertha?page=3
Here’s an article with some photos. It says it can “swallow” boulders 3 ft. in diameter. I’m guessing that what look like openings in the cutting face ARE openings so that the material can make its way from from the face, through the cutting head, and then onto conveyors out the back of the tunnel to get hauled away.
It seems that they must be taking their time in exploring what the object is on the off chance that it is some sort of man made object such as a pipe (doubtful at 80-feet deep), building footing (also doubtful), or whatever.
I’m still not up to speed on the whole pressurized thing. If it is just the face of the bit that is pressurized - then how could they have all of the holes in the bit to allow the waste material through? So maybe the pressure has something to do with why they can’t send some miners down with jackleg drills, etc. to explore.
Anyway - it will be interesting to see what it is, and more importantly, how they solve the problem.