Hanford Downwinders: Iodine in the Air for Forty-One Years

On December second and third of nineteen forty-nine, managers at the Hanford nuclear site in southeastern Washington deliberately released a large cloud of radioactive iodine one thirty-one into the atmosphere over the Columbia Plateau. It was a test. They wanted to know how far the particles would drift, how ground-level monitoring would respond, whether their instruments worked as designed. They did not tell the people who lived downwind. They called the experiment the Green Run.

This was not an aberration. Between nineteen forty-four, when the B Reactor first began producing plutonium, and nineteen seventy-one, Hanford's operations released iodine one thirty-one and other radioactive isotopes into the air and into the Columbia River as a matter of routine. The releases were classified. The people living in the Tri-Cities, across the Yakima Valley, and throughout the Columbia Plateau breathed the air, drank the milk, and ate produce grown in contaminated soil. Many of them were children. Iodine one thirty-one concentrates in the thyroid, particularly in young bodies still developing.

The public did not learn the full scope of what had been released over their homes until February of nineteen eighty-six, when the Department of Energy declassified nineteen thousand pages of internal documents. The documents showed that the contamination had been known, tracked, and classified for decades. Approximately thirty thousand people had lived in the primary downwind corridor during the years of heaviest release.

The Washington State Department of Health and independent researchers subsequently documented elevated rates of thyroid cancer among downwinder communities. The precise causal relationship between specific releases and specific disease cases remains contested in the epidemiological literature, as it so often does when the contamination and the illness are separated by decades and the records were deliberately kept secret for most of that time.

The cleanup of Hanford is projected to cost more than one hundred billion dollars. The work is expected to continue past twenty sixty. The B Reactor tour, which brings visitors in from a secured checkpoint, is eleven miles from the most contaminated sections of the site.