Tuesday marks the 50th anniversary of the nuclear meltdown–the first ever in the United States–at the Atomics International field in the Santa Susana Mountains. The 1959 accident has been linked to lasting health problems in the nearby San Fernando Valley and throughout greater Los Angeles, and efforts are underway to launch a modern-day investigation of the aftermath.

On July 14, 1959, an overnight power surge resulted in the release of radioactive material into the atmosphere. According to lab employee John Pace, plant supervisors feared that some of the radioactive gas had made its way across the heavily-populated San Fernando Valley.

Despite safety concerns, plant operators attempted to cover up any evidence of a meltdown, assuring the public that no radioactive material had been released. The plant was immediately disassembled following the incident, all the while spewing the colorless radioactive gas into the Southern California sky.

The nuclear meltdown went largely unnoticed until 1979 when research students from UCLA uncovered government documents describing the possible release of radioactive gases, worrying residents about the long-term effects of nuclear testing in the area. A study released in 2006 suggested that the accident could have caused between 260 and 1,800 deaths in the decades since. A Boeing-commissioned study, however, disputed those findings, saying that cancer deaths of employees working in the compound were less than that of the general population.

Los Angeles resident Holly Huff, who was eight years old at the time of incident, says the contaminants may have contributed to her acute health problems. Last December, Huff was diagnosed with leukemia and thryroid cancer. Like many other San Fernando Valley residents, Huff was unaware of the danger that the meltdown and the continued nuclear and rocket testing at the site posed to her health.

Much like the residents of Libby, MT, the asbestos-poisoned mining community, San Fernando Valley residents continue to fight for their health and safety. Five decades after the meltdown, efforts are still underway to remove traces of radioactive material from the 2,850-acre facility. The Environmental Protection Agency plans to spend $40 million of stimulus funding to conduct a thorough survey of the Santa Susana site, and the Department of Energy is currently preparing an environmental impact study under a court order. Last year, Senate Bill 990 went into effect, ordering NASA, Boeing and the Department of Energy to reduce contaminants to levels suitable for residential and agricultural use–a process which may take up to a decade to complete.

photo credit: Swobodin’s Flickr photostream (creative commons)