He's given a TED talk too, https://www.ted.com/talks/andres_ruzo_the_mythical_boiling_river_of_the_amazonYouTube
When Andrés Ruzo was a boy, his grandfather would tell him tales of a mythical city of gold deep in the heart of the Peruvian jungle. Though never believing the stories to be true, the legend of the lost city stuck with him into adulthood. Years later, as a geothermal scientist, Ruzo decided to investigate. To his surprise, he discovered an incredulous river deep in the Amazon, with water hot enough to kill a human. Historically a place of pilgrimage for shamans and sorcerers, the river now faces increasing threats from poachers, loggers and squatters. Now, Ruzo is working hard to protect it.