COPIAPO, Chile: A third drilling rig being used in the effort to reach 33 trapped Chilean miners made good progress in its first day of operation, offering hope for accelerating the rescue, officials said Monday.
The oil-drilling RIG-421 had burrowed some 23 meters (75 feet) in less than 24 hours early Monday, a quicker pace than the two other drilling machines being used simultaneously.
The latest rig is part of the so-called Plan C in the rescue effort that would dig down some 597 meters (1,958 feet) to get to the miners trapped since a cave-in August 5.
The RIG-421 put into service Sunday can dig an estimated 20 to 40 meters (65 to 130 feet) per day, and also has an advantage over the other two rigs because it drills a hole of 66 centimeters (25 inches) in diameter from which the miners can be rescued without additional widening.
Whichever escape tunnel is finished first will have to accommodate a special bullet-shaped capsule which will haul each of the miners to the surface.
Early in the ordeal, authorities warned that it would be a challenge to extract the miners before Christmas, and then said a rescue was likely in November.
Mining Minister Laurence Golborne has not officially changed the timetable but sounded more upbeat on Sunday.
"We have always spoken of the first days of November, but the plans now are slightly ahead of schedule," he said at the mine.
"We are gaining a day here and a day there, but we do not claim victory or generate excessive expectations, since we are talking about an inexact science," Golborne said, noting the complexities and safety concerns of drilling through layers of granite rock.
A 30-centimeter-wide (12-inch) rescue hole reached the miners last week week but it must be widened before anyone could be safely lifted out.
The T-130 drill, which completed its 630-meter (2,070-foot) shaft and broke through Friday to the tunnel where the miners were holed up, was the second machine brought in to bore a rescue hole.
The first drill, a slower Strata 950 hydraulic bore, has so far descended only 320 meters (1,056 feet) into the ground.
Each of those would be expanded to a planned 70 centimeters (27.5 inches) in diameter to accommodate the miners.
The men -- 32 Chileans and one Bolivian -- were trapped in the mine August 5 after a tunnel collapse, and have survived underground longer than anyone on record.
They are being supplied with food, water, medicine and entertainment through three supply holes, which also carry communication lines to the surface, where family members were camped at the entrance.
BDST: 05:17 HRS, September 21, 2010
ZHS