Transcript for Thai cave rescue: the race against the rain

Next, to thailand.and theace to free the young er team trapped in a cave with monsoon rains apchg. A new at the massive eff undeund. A team of divers entering the cave. Wos drill through rock, opening up narrow passages and laying Draine pipes. They are despe to lower T water level and free the boy before the rain can flood the cave again. ABC's James LAN on the scene again fo tight. Reporter: With monsoon rains clg in, the race is on. Rescue wrsn that Thai cave drilling through rock. Layinges, constructing a dam divert water. And that could M a ial difference. Ofals say it willremove drastically more W than the pumps E. The goal, reduce the water level inside to give those trapped ys a chance to escape. Nees tonight showing the pr. Areas in front of the cave, on foot. T part of that treacherous 2.9-mile maze inclhambers filled to the ceilwith water, narrow tunnels S will work to expand. Right ivg is the only way out. But als say that option is off the table for thys. The fear they could pa the danger, too great. Look how rough the cur I is professional fighting to hold onto a guide rope. The latest plan, when the water recedes, float the boys out one-by-one with life jackets. One official telling me the rescue can begin once the water fallselow neck lev in the bmerged caves. At thesurface, ambces and paramedics run drills, R to treahe when they emerge. But they must work quickly. That heavy rcould begin in the next 24 hour five to more T eight inches cast in the region. The water I the cav is going toill up, ? And it's going to be hardor the Navy S.E.A.L. To to get the kids out. Reporter: We traveled to a cave about 15 minutes from WHE the boys are trapped to get a look at what they face. As you go further in, that's where you start to see water like this. And look, it gets very, high. You've gotagged roc face, murky ter. It gets worse, as we deeper into the cave. This just narrower and narrower. And J imagine this, but full of water. 'S cold, it's daitmells,me, these kids B here for so long hese conditions, it's kind of unimaginable. At camp, exhausted divers going back aor in shifts. "Six hours in, six hours out," this one says. A grueling effort Ave those boys. A 12-hour trip in total, ose dives truly reless. James Longman joins U now F outside that cave. Mes, W heard in your report a that ca, more rain coming.d E risk of that cave flooding again Reporter: Yes, Tom. Rememb these boys got stu INT cave because of flash flnghe first place. So, authorities here are watching the weather closely.anore water in Thate is very dangerous. It could destroy thegrs they've made and threat those boysll sitting on that muddy nk.m? So man will be monitoring that mieather there in thailand.james, thank you.

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