Does anyone know any more detail about their plan to drill down to him - and is similar rescues have been preformed this way? I'd be interested if the air he wa

Does anyone know any more detail about their plan to drill down to him - and is similar rescues have been preformed this way? I'd be interested if the air he was breathing was 'trapped' and if drilling down would release it, and drown him, or if the air had a slow route in and out of the pocket he was in. Fascinating stuff.