An earthquake of 7.8 magnitude hit an area of China about 17 years ago, collapsing a mine that was recently re-opened, what they discovered is a survivor! 

This man had remained trapped underground with the bodies of 78 of his dead coworkers. He managed to give a proper burial to all 78 of his fallen comrades. He survived on rations of rice and water that had been stored underground. Seventeen years later of course has it's physical and mental stress added to someones lack of sunshine, proper food and care. He was able to get fresh air through one air duct that was not collapsed that was still connected to the outside. He also ate moss to gain some vitamins he needed.

He did manage to break a world record being underground the longest, previously held by a man in Britain, 142 days underground. Though I imagine he would prefer not to have broken any record and have the 17 years of his life back.