Ok, let's clear a few things up, I have been down to check out the grinding crews handiwork and let me tell you it is disgraceful! I have personally removed hundreds maybe thousands of bolts during the Titanium rebolting in Thailand over the last 8 years, so I feel I can talk with some experience in bolt removal.
I was shocked with what I saw when I first caught a glimpse of the arch last week, there were some 60mm x 60mm holes grinded into the arch itself? I am not sure what method of bolt removal you guys were attempting down there, it's real amateur work guys.
(The photo posted above of the grinded off ring is about the neatest one I saw out of the whole bunch)
I imagine too embarrassed to post one of the others with the 60mm deep hole cut out.
Also the bolts have been removed without any of the chalk removed! It will be almost impossible to do now without the bolts. All I can say it was a rush job, you do a job once the right way guys not a rush job and now have to return to sort out all your mistakes because you were in such a hurry. As the old saying goes "measure twice cut once" maybe you guys had a certain deadline to meet? And that's why you did such a half arsed amateur job. Nice work team ;-)