"Everybody was thinking, 'How can we repair the reactor, and save it and still have our jobs ... and not just say it's over with,'" said John Pace, a former trainee at the Atomics International field laboratory.
Pace, who was only 20 years old at the time of the accident, says officials wanted to keep it a secret and kept switching the reactor on and off for weeks afterwards. Today he joined the fight for a speedy cleanup of the site.
"This was one of the most serious accidents of nuclear history to date. And it was kept secret for two decades. Now half a century later, they're still trying to clean up the mess at this site," said Dan Hirsch, Committee to Bridge the Gap.
John Pace says he still has health problems, which he believes are related to the radiation leak.
"I still have trouble to this day with my lungs. I have to watch on perfume or smoking. I can't be around anything with chemicals, like cleaning chemicals," said Pace.
Local residents who were living in the area at the time of meltdown blame the accident for cancers and other illnesses
"I've got a leukemia, it's a blood leukemia ... CLL. I was just diagnosed in January. And I've got a couple of thyroid issues," said Holly Huff, a former resident.
The Environmental Protection Agency plans to spend another $40 million in stimulus money on a radioactive survey of the site.