If you were looking for someone to oversee nuclear reactor issues, you probably couldn’t ask for better credentials than Arnie Gundersen’s. He has a Master’s degree in nuclear engineering and an Atomic Energy Commission fellowship. He holds a nuclear safety patent, was a licensed reactor operator, and managed and coordinated projects at dozens of U.S. nuclear power plants. Hired by a nuclear consulting firm in 1979, he served as an expert witness in the investigation of the nuclear accident at Three Mile Island and co-authored the first edition of the DOE Decommissioning Handbook.

As a senior VP at the company, his career was solid—until he discovered radioactive material in an accounting safe and told the boss that was a violation of radiation safety standards. Instead of securing the material, the boss fired Gundersen and saw that he was blacklisted in the industry. Despite all his credentials, he could not find an appropriate job.

Over the next three years, Gundersen and his family were continually awakened by harassing phone calls in the middle of the night. He bought a large dog to warn of intruders.

Gundersen worked as a dump truck driver and then as a teacher, at one-sixth his former salary. He and his wife exhausted their savings, their house was foreclosed, and his health deteriorated. He considered staging a suicide to look like an accident so his family would have his insurance money but decided that he’d fight on for nuclear safety rather than letting the dangers persist.

He and his wife founded the Fairewinds Energy Education, a nonprofit that campaigns for nuclear safety. Gundersen testifies before regulatory commissions and publishes reports on reliability, safety, and radiation issues. He’s considered a prime expert in the field, regularly interviewed for his expertise.