"If this had been a vertical hole we probably could have done it in half the time," said Fisher. It was an emotional roller-coaster-ride — with no guarantee of success, he said.
The 5 1/2-inch-diameter pilot hole his drills followed down into firm rock laced with quartzite had "really threaded the needle" between several mine shafts.
But the rock is so hard that only the top few hundred feet of the escape hole needed to be reinforced with a steel sleeve. Workers were welding together about 16 steel pipes for that purpose.
The completion of the escape shaft Saturday morning caused bedlam in the tent city known as Camp Hope, where the miners' relatives have held vigil since a cave-in sealed off the gold and copper mine Aug 5.
The drill that punctured through worked constantly for 28 days with a few breaks when some of its hammers fractured, once on a 6 1/2-foot roof bolt used to support mine shaft ribs.
The escape capsules, equipped with spring-loaded wheels that will press against the hole's walls, will be lowered into the hole via a winch and the trapped miners brought up one by one. Encasing the full shaft would have added another week or so before the rescue could begin — if it could actually be done. Some miners' families wanted the entire shaft lined.
But the consensus of geologists and engineers was that there was no need.
"I don't think there's any risk of collapse," said Mario Medina Mejia, a geologist in Copiapo, the nearby town where some of the miners live. "It's a hole made into virgin rock."
Such assurances hardly calm the nerves of Rosa Gomez, the second of four daughters of Mario Gomez, who at 63 is the oldest miner trapped below.
"I'm afraid that at the moment the capsule comes up he'll panic," she said.
Gomez, 28, said her nerves were shot and she was physically spent.
"These two months have felt like two years."
Other relatives of the trapped miners had to contend with the incessant crush of more than 750 accredited journalists from all over the globe after the previous day's breakthrough. Many relatives simply disappeared from the mine on Sunday.
Carolina Lobos, waiting at the mine for her father, Franklin, to surface, was simply overwhelmed.
"They're besieging you every five minutes," she said. "You sit down down and yet another journalist shows up."