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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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WEAPON RADIOACTIVITY SPREAD BY DETONATION IMPACT 338897 On January 17, 1966, a B-52 aircraft carrying four nuclear bombs collided with a KC-135 tanker over Palomares, Spain, during refueling operations. Four bombs broke free in the crash as the disabled aircraft plummeted near the village. One fell in a steep bank of soft earth and did not detonate. One fell into the sea and was later recovered. However, the HE components of two weapons did detonate upon impact; one in low mountains and the other on land used for agriculture. The wind velocity at the impact site was approximately 30 knots at the time of the impact and the area contaminated by plutonium from the detonated weapons was long and narrow. The area con taminated from 3.2 to 32 p,Ci/m^ was slightly over one-half mile long and one-sixteenth of a mile wide, with plutonium detectable to a distance of approximately two miles. As mentioned above, the high explosives in two of the weapons detonated on impact. The quantity of plutonium involved in these weapons remains classified. Evidentially, much of the plutonium involved in these detona tions was converted into a fine, oxide and was dispersed by the 30 knots wind which prevailed at the time of the accident. The Air Force survey showed that the 32 yCi/m^ level covered something over five acres with an additional 41 acres contaminated to more than about 3.2 microcuries per square meter. An additional 500 acres were found to be contaminated to The Air Force did careful appraisals to learn the whereabouts of all radio active material and radioactive contamination following the accident. Most of the aircraft wreckage was found to be uncontaminated or to have negligible contamination. All of the wreckage with slight contamination was gathered and disposed of by dumping in deep, remote Atlantic waters. More contaminated wreckage was picked up, packaged, and transported to the United States for disposal. No plutonium or tritium contamination was found in the sea water at any time following the accident nor was any tritium found at the impact sites or anywhere in the Palomares area higher than background. Shortly after the accident. United States experts met with officials from the Spanish Government to advise and assist Spain in handling this con taminating accident, and to decide upon criteria for disposal of contami- ^ nated soil. It was agreed that soils contaminated with more than 32 pUi/m would have the top 10 centimeters (four inches) removed for disposal in the United States. Areas with less contamination (3.2 to 32 pCi/m^) would be plowed to a depth of about 30 centimeters.
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Based on the agreement reached with Spain on the decontamination process the top four inches of soil for the area which had been contaminated at greater than 32 p,Ci/m^ were removed from approximately 5.4 acres and placed in drums for shipment to a United States storage site; approximately 550 additional acres which had been contaminated to less than 32 ^Ci/m^ were plowed to a depth of about 30 centimeters. While it had been agreed to plow areas having contamination levels greater than 32 jaCi/m^, in the actual field operation areas plowed included all down to about 3.2 p,Ci/m2 where feasible. Crops grown on soil op the area which had been contaminated to more than 32 jaCi/m^ were also shipped to the United.States for burial, while those grown on the deep-plowed soil in the area which had been contaminated to less than that figure were burned at the sea shore on days when the wind was blowing toward the sea. After the decontamination was finished, lung counts for radioactivity were taken on the 100 villagers most likely affected and no positive counts were found in the group. Urine samples for plutonium were negative for 70 persons and showed only insigificant amounts for the others (0.1 to 0.2 dpm in a 24 hour sample). In 1971, six years after the accident, there appeared to be little change in the community from the time before the accident. Farming habits have . changed, but mostly due to other factors such as drought, flash flooding, and economics. Followup studies show little change in exposed persons and none is expected.