CHIANG RAI: Conditions for the 12 schoolboys and their coach trapped inside the Tham Luang cave complex are now suitable for evacuation, rescue operation chief Narongsak Osottanakorn said on Saturday (Jul 7) as the mission to retrieve them risks facing more challenges from monsoon rains forecast for the weekend.

"For two to three days now, the conditions of water, air and children’s health have so far been most suitable," he told reporters outside the cave network where a football team from Chiang Rai province has been stranded since Jun 23.



"Still we have to talk it through before making any decision on what exactly we can do."

At present, the authorities’ main concern is the levels of oxygen and carbon dioxide in the flooded chamber where the group is stranded.

A Thai police officer stands guard near oxygen tanks as rescue operations continue for 12 boys and their coach trapped at Tham Luang cave at Khun Nam Nang Non Forest Park in the Mae Sai district of Chiang Rai province on Jul 6, 2018. (Photo: AFP)

Since the rescue operation began on Monday, oxygen levels have fallen inside the 10km cave complex as more rescuers join the operation.



Every inhalation means more oxygen is taken from the air pockets inside the cave complex and every exhalation produces more carbon dioxide.

If the human body lacks oxygen, the brain will begin to function slowly before going into a coma.



"Oxygen isn’t the only factor we’re worried about. The level of carbon dioxide in the cave system also matters," Narongsak said.

"When oxygen in our blood is low, more carbon dioxide will enter the blood stream. If it reaches a certain level, it could harm our body, no matter how much oxygen there is in the air.

"The only thing we can do now is to increase oxygen for them."





PERILS FACED BY RESCUE CREWS

On Friday, retired Navy Petty Officer 1st Class Saman Kunan died on his way out of the Tham Luang cave complex after going in to supply one of the chambers with air tanks.

He used to work for the Thai navy SEAL, and his loss has brought grief not only to his former colleagues but also people in Thailand and beyond.

His death highlights the perils of the operation to extract the football team from deep inside the waterlogged cave, raising questions about the feasibility of bringing the boys out the same way.

Inside the Tham Luang cave network, rescuers work around the clock to supply air tanks to the survivors.

Fresh air continues to be pumped in while the number of people entering the compound has been limited to stop oxygen from depleting too fast.

“It gets trickier when you reach the small chamber where the children are trapped," said Narongsak.

"Divers will be so exhausted after hours of walking and diving. When they breathe heavily, the oxygen level will shrink further. The kids then become exposed to more carbon dioxide.

“At this stage, we’ll send in as few people as possible but a lot of air tanks. At any given time, at least four people stay with the kids.”

The route to where the Thai boys and their football coach are trapped in the cave. (Graphic: Rafa Estrada)

STRANDED 13 LEARN DIVING, BUT RISKS REMAIN

According to the operation chief, the stranded 13 have learnt how to dive and breathe with masks. Still, there are risks to be considered before evacuation can take place.

The authorities have yet to determine how they will retrieve the boys and their coach. Two main options include scuba diving and extracting them through a shaft.

The rescue team hopes to find an opening in the ground on top of the mountain where the Tham Luang cave complex is located that could lead them down to the survivors.

While divers supply the stranded with food and air, hundreds of people comb the forest above them in search for a hole that could lead down to their chamber. More than 100 holes have been drilled but only 18 of them have some potential.

“The best depth we have is about 400 metres. Still that hole isn’t near where they are. No technology has helped us locate them from the top so far,” Narongsak said.

Locating the boys and their coach from atop the mountain is an extremely difficult task, he added, comparing it to shooting at a green target in a lush green forest.

“We have absolutely no idea where our target is or how we can drill towards it to feed more air into their chamber or even get them out.”

Boys from the under-16 football team covered in hypothermia blankets react to the camera in Chiang Rai, Jul 3, 2018. (Image: Reuters/Thai Navy Seal)

SURVIVORS' SPACE COULD BE SUBMERGED WITH HEAVY RAINFALL

Based on cave experts who have studied the Tham Luang cave complex, its water levels remain high during the wet season.

Narongsak said the area where the survivors sit could be submerged after heavy rains, which would leave them only a small space of less than 10 square metres.

“When the water comes, it comes rushing like a waterfall," he said.

So we’re racing against time and everyone is stressed. It’s like we’re all carrying this mountain on our shoulders.”

The clock is ticking.

The Thai Meteorological Department has forecast rains in many parts of Chiang Rai over the weekend. Authorities are fully aware both evacuation options take time and a lot of planning to prevent unnecessary injuries and loss.

“What we’re targeting is to have as little water as possible. The perfect situation is for the cave complex to be dry. But it’s impossible now. It has to be in December or January,” Narongsak said.

“We have to find if there are any other solutions but once it becomes risky, we have to make a decision. We’ll do our best. Nobody wants to fail.”





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