SANTIAGO, -- Chilean President Sebastian Pinera said a new drill started to carve a third rescue tunnel to save miners trapped in a copper mine in northern Chile since Aug. 5.az` The so-called Plan C for rescuing the 33 miners trapped 700 meters underground involves a 45-meter-tall oil drill that can dig 20-30 meters a day. The first two drills had to gradually expand the diameter of the narrow holes they bored while the latest drill, Rig 24, can easily carve a 28-inch-wide shaft, which is wide enough to pull a man out through a single pass. "Today for the first time the three machines will work at the same time. We do not know which one is going to achieve the goal, but we are sure that with God's help they will make it," said Pinera. The president, accompanied by Chilean writer Isabel Allende, visited the site to mark Chile's bicentennial of independence with the miners, who became national heroes when they were found still alive on Aug. 22. "I am proud of being Chilean and the president of Chile, because the spirit that lives in San Jose mine is the one we want to be forever in our country," Pinera said. On Friday, Rescue Plan B finally broke through to 630 meters underground, puncturing the top of a passage near the shelter where the miners took refuge. Once Plan C machine reaches the miners, the rescuers would fortify the walls of the tunnel with iron tubing to prevent it from collapsing when the miners are pulled out to the surface. If everything goes well, the miners could start their escape as early as Oct. 18. However, both the president and Mining Minister Laurence Golborne remained conservative. "We are making small advances, but we do not want to generate too many expectations. It is scheduled to end at the beginning of November, but if we can do it better, we will do it, " Golborne said.