From Beyond Nuclear Internatiional
July 16, 2018
A 90 million gallon nuclear tragedy
The uranium tailings spill at Church Rock, NM was the largest single release of radioactive contamination in US history
By Linda Pentz Gunter
On July 16, 1979, the worst accidental release of radioactive waste in U.S. history happened at the Church Rock uranium mine and mill site. While the Three Mile Island accident (that same year) is well known, the enormous radioactive spill in New Mexico has been kept quiet. It is the U.S. nuclear accident that almost no one knows about.
Just 14 weeks after the Three Mile Island reactor accident, and 34 years to the day after the Trinity atomic test, the small community of Church Rock, New Mexico became the scene of another nuclear tragedy.
Ninety million gallons of liquid radioactive waste, and eleven hundred tons of solid mill wastes, burst through a broken dam wall at the Church Rock uranium mill facility, creating a flood of deadly effluents that permanently contaminated the Puerco River.
No one knows exactly how much radioactivity was released into the air during the Three Mile Island accident. The site monitors were shut down after their measurements of radioactive releases went off the scale.
But the American public knows even less about the Church Rock spill and, five weeks after it occurred, the mine and mill operator, United Nuclear Corporation (UNC), was back in business as if nothing had happened. Today, the Church Rock accident is acknowledged as likely the largest single release of radioactive contamination ever to take place in U.S. history (outside of the atomic bomb tests).
Why is the Church Rock spill – that washed into gullies, contaminated fields and the animals that grazed there, and made drinking water deadly – so anonymous in the annals of our nuclear history? Perhaps the answer lies in where it took place and who it affected.
Church Rock was a small farming community of Native Americans, mainly Navajo, eking out a subsistence living off the arid Southwestern land. Nearby, several hundred million gallons of liquid uranium mill tailings were sitting in a pond waiting for evaporation to leave behind solid tailings for storage. On the morning of July 16, 1979, part of the dam wall collapsed, releasing a roaring flood of radioactive water and sludge.