GWEN IFILL: NOVA's mine rescue story airs tonight on most PBS stations. Margaret Warner has more now with one of the architects of the Plan B effort.
MARGARET WARNER: And drilling the shaft to reach the trapped miners was very much a team effort. One U.S. company, Drillers Supply International of Houston, made the drill pipe used in Plan B.
Its president, Greg Hall, was featured at the end of the "NOVA" clip. He also served as a general contractor of the project, bringing together Brandon Fisher and his hammering drill head technology with riggers, drillers and others.
And Greg Hall joins us now to tell us more about it. You were seeing this for the first time while we watched it here right now.
GREG HALL: Oh, yes.
MARGARET WARNER: Are you still pinching yourself that it actually worked?
GREG HALL: I really am. It's -- every now and then, I still wake up at night worrying about the miners, because it was such a long, drawn-out process getting them out. But it's just so wonderful to see that and to relive that.
MARGARET WARNER: Well, congratulations.
GREG HALL: Thank you.
MARGARET WARNER: Explain a little more what made this, as an engineering feat, so daring, so unusual, this Plan B concept?
GREG HALL: Well, the Plan B concept, really, we were trying to drill down almost a half-of-a-mile through very hard rock.
The borehole that we were following which had -- as you saw there, had many different changes. It had changes in orientation and it had three curves in it. Normally, in a normal job, we would abandon that type of hole because it had so many curves in it.
But we knew, if we followed that borehole down, we had to reach the miners. So, we had no choice but to try to follow that. And to go through that hard rock with those large diameters was really a technical challenge.
MARGARET WARNER: Now, here you were, a U.S. company. You had other U.S. companies involved. Was it hard to persuade the Chilean government to let you all make a stab at this?
GREG HALL: Not too much. I have actually been doing business in Chile for 25 years. And I own a manufacturing company that's been there for 19 years. We were actually supplying the rigs that originally found the miners after 17 days.
MARGARET WARNER: But I thought I heard that it was hard at least for Brandon Fisher to get people to even listen to this idea.
GREG HALL: Right. I was working on a plan to try to better the time that was being made. Then I got a call from a mutual acquaintance who told me that Brandon had an idea, but couldn't get anybody to listen to him. So, I called Brandon, looked at it. And, really, his was -- his plan to use his hammers was the last piece of the puzzle that I needed to put the entire proposal together.
MARGARET WARNER: OK. And what was special about his hammers?
GREG HALL: Well, the normal way that you would drill this type of hole is using a very large percussion hammer, which has a 600-pound piston and beats very aggressively.
The problem in this is, we had men down there, and we couldn't stand the vibration. His cluster hammer is a low-profile, low-torque, uses four or five small hammers, and so it hits very quickly, but not as aggressive, and doesn't cause as much vibration.
MARGARET WARNER: Now, you did have one at least near disaster, didn't you, at some point?
GREG HALL: We had several. Which one are you talking about?
MARGARET WARNER: Well, I was talking about the one where one of those hammers fell off or broke off.
GREG HALL: Exactly. One of the things, with the cluster hammers, they're designed and made to drill vertical, in other words, to drill with every point touching the ground. As you saw from the video, we had like a curve. So, during that curve, only parts of the hammer were touching.
And it actually broke the hammer. And one of the hammers went down. We also lost a bit. And that was a bit of a trouble, where the government wasn't sure if we needed to continue or not. But, again, having been there for 20 years, we were able to assure them that the plan would work. And they, thank goodness, continued to allow us to drill.
MARGARET WARNER: We read and saw a lot about how the families, the wives and the families of the miners really bonded in that camp. What was it like for you all who were working on it, you and people working on plans A and B? Did you have a similar kind of experience?
GREG HALL: I can't speak for Plan A and Plan C, because they were -- but, in Plan B, we had a little camp, because we pretty much lived on the mine in a little container.
And we actually started calling ourself the family. And it was my people. I had two of my Chilean people there 24/7, Brandon with his people, all of the people that came from Afghanistan. And we became a family. And we really bonded, because, you know, it was such a crucible of emotions, knowing what we were drilling for.
And -- but we did. We became very, very tight.
MARGARET WARNER: Do you think this technology that you all developed or used in this way will now have other applications?
GREG HALL: I certainly do. We have actually been contacted by the Chilean government, Codelco, because this was a new way to show them how to drill large diameters very quickly.
MARGARET WARNER: You are about to -- I hope up don't mind me bringing this up -- about to be ordained a deacon in the Catholic Church.
GREG HALL: Yes.
MARGARET WARNER: How much was faith part of what kept you going here?
GREG HALL: For me, faith was very much of it. I was asked the question, how much did this job change my faith?
And I made this point. It was the other way around. We did have a couple -- a few times where, technologically, we were out of answers, we were trapped. And I had no idea -- none of us had any idea what to do.
And we resorted to prayer. And I am firmly convinced that divine providence drilled this job. As a matter of fact, the man that was in charge of Plan A, when I was leaving -- he is a good friend of mine -- he told me, he said: "Greg, you know something? That job was impossible. You could not drill that. God drilled that hole."
And I think he was right. And I was just glad to have such a good seat.
MARGARET WARNER: Well, I know the miners were glad to have you. Greg Hall, thank you.
GREG HALL: Thank you.