Rescuers hope to drill through the last third of the debris blocking a collapsed tunnel in the Indian Himalayas by early on Thursday to reach 41 workers trapped for 10 days, an official said, so long as there are no new hurdles.
The men have been stuck in the 4.5-km tunnel in Uttarakhand state since it caved in early on November 12 and are safe, authorities have said, with access to light, oxygen, food, water and medicines.
Authorities have not said what caused the tunnel collapse, but the region is prone to landslides, earthquakes and floods. Efforts to bring the men out have been slowed by snags in drilling in the mountainous terrain.
By Wednesday, rescuers drilled through 42 m of an estimated 60 m that need to be cleared in order to push through a pipe wide enough for the men to crawl out, said Mahmood Ahmed, an official of the firm building the tunnel.
"Many hurdles can emerge, but if they don’t, we hope that by late in the night or early tomorrow we all will get some good news," Ahmed, the managing director of the National Highways and Infrastructure Development Corporation (NHIDCL), told reporters.
Possible obstructions in the debris could include large boulders, stones and metal girders, he said, adding that welding together the evacuation pipe needed more time than drilling.
First images from within the tunnel showed workers in white and yellow hardhats standing in the confined space and communicating with rescuers on Tuesday, after a medical endoscopy camera was pushed through a smaller pipeline.
The trapped men have been receiving fruits and cooked food items after a second, larger pipeline was pushed through on Monday.
Toiletries and clothing have also been pushed through, said Neeraj Khairwal, a rescue coordination official.
"The workers are very positive and they are in a very good mental state."
Physicians and chest specialists are among 15 doctors at the site, said R.C.S. Panwar, the district's chief medical officer, with 40 ambulances set to be placed on standby.
The anxious families of 11 of the 41 trapped men have reached the accident site, eager to see them rescued. Those trapped are low-wage workers, most of them from poor states in India's north and east.