Transcript for Rescue operators weigh options to save 13 people trapped in a Thai cave: Part 3

Reporter: That miracle on day leaves the world elecied-and relieve all 12 long lost boys and their coach edether, exhausted, hungry. But alive. Many people are coming. Many, many people. We are the first. People to come. Reporter: The families outside the cave are overjoyed, om is ready to make her 11-year-old his favorite meal. That celebration is amplified justown the road at the sch where sixthe boys are students. I was really happy wh know my friend is alive teacher They made an announcement. Hing went up I cheers. So what youaring here is a prayer being said by that student there forhe fellow students in the cave. Check this out. 2,800 students who are here, six of them are at cave right ter Carl Henderson tells me about one particularly popular boy in that trapped P nicknamed biw. Teacher his best friend went and sat is his chair and said, , I'm gointo sit hertill he comes back. Every day. Literally to keep his S warm. Yes. Orter: He show C biw's classmates have written, and messages on the blacrd for hi This says 'we miss our friend so much." Eporter: Iat with some of his friendo tell me he's drummer in the marching band and a fun loving, spirited kid. Talking, eat Talking and eating in class? Yes! Reporter: Ands the show me, he is not a brtist. So biw did this design? Yeah. Wow. He's good! Yes. Reporter: The boys have been found about 2 1/2 miles from entrance, pchedn a rise from the . Ev further than the dry rescuers had been tarng as their location. Now on day 11 a new mission begins. Getting the boys' strength back and then getting them out. Hat condition are they in? They're very weak. Veryk. H, but they're all alive. So 'going to bay. GU, but yes. Reporter: The world Wes as ty'mined by medical rts who surisingly find them in relatively good health. My health is good. Rorter: One boy flashes a "V" for victory, but I clear they've lost weight after survg N the WATE dripng off the cave ceiling. While they're obviously hung solid foodds to be reinuced carefully These are the kinds of military rations that divers are im into the cave to give to the boys. Things that are protein-rich, full of nutrients to build up their strengththat they cot out, but alsings that they can swallow because they've been so long without food. Rter: Up inhe rescue village, anxiety is rising, more rain irecast, adding to the pressure to act fast. The entire world is asking when will E 12 boys and their soccer coach see the light of day? The focus is on how on Earth to get them out, because there W options Frankl Repor option one seems obvious, have them swim out with the divers. T to see what kif physical environment they'd be pushing through, I visitearby cave, though dry, it gave me a are so narrow, you kind of have to just scoot on your . Or crawl, to get through. Imagine doing this underwater. With 60 to 70 pounds gear, tanks, having to have your swi flippers with you, then imagine having to Dr kid throu th as well. Reporter: They'll be navigating through even rougher rain to get O If thhole thing WER flooded, you'd find th actual entrance thaty little ENTR, when visility is absolutely zero. Rter: But Makin complex situation even worse, sof these Bo don't kno how to swim, muc less scuba dive. A very black environment, which could potentially killnside a Caits not a good environment to learn in. Reporter: This video shows rescivers fighting Ast those dangerously strong currents. Some of the British divers are somethe best in the world, doing that who found the kids, and they're reporting back that it was one of the M challenginves that they had ever done. Your margin of error is basically nothing. Reporter: T mask is tried out on a boy O similarsize, as the ping for this potentially deadly optionevs up. They're in a totally alien environmscared out of wi Reporter: Bill Whitehouse is with the British cave rescue council. Several of his divers are leading the char they could endanger not only themselves, the person who is going to dive the out.they could dislodg their own face mask it would be incredible to expect them to do without panicki Reporter: Option two, drill through the mountain from ab and pull boys out of the cave. But this option involves a wholelot of guesswork. You wouldn't want to drop rockto the existing pay and make it completely impassable, and you also wouldn't want to drill close enough to the boys such that would put them in danger from being injured Alling rocks. Reporter: Third option, do notng and wait, for months until the rainy se ends in November. Then they could simply walk out. But a further flooding could cut off their precar underground rch. Ey had Waid hs during this rain season then there was no telling jusw much higher the water could get inside. Reporter: D 12, a flurry activity and emergency drills outside the cave entrance, as rers franticallyh forward on all options. An attempt is made to lay a phone cable all the way in to the boys but it fails. Your biggest LEM is communicn formation. Information is incredibly precious during a caescue and evtiny bit of information you got is often hard fought and hard won. Repor D 13, a dam is built outside divert water from the cave, proteg it from a worriso deluge of rain expected any day now. We're heading into oon season no one knows when but it's coming and they have to get th boys out F side the cave, a command center is established in what' called chamber three, stocked with gear, food and medical supplies. Underwater-divers are illing guide ropes along the route, and rowsair tanks at reg intervals -- resupply along the way.jaers are USO smash rock to clear room in tighter spots. Ou know you're tal about a six-houre. And the main issue they had was to try to ensuhat the boys had spend as little time underwater as pole. Repor but a new threat could forceaster action. Oxygen levels inside are dropping and a tragedyes the dangers inside all too real. A former Thai Navy diver has

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