The Palomares Bombs
On January 17, 1966, an SAC B-52 had a mid-air collision with a KC-135 tanker, while refueling over Palomares, Spain.
The B-52 was carrying four thermonuclear B28 bombs. The bomber had begun the mission at Seymour Johnson AFB, North Carolina. The KC-135 had come from the Moron Air Base, Spain. All four KC-135 crew members were killed, while four of the seven B-52 crew parachuted to safety.
The four bombs fell in a line roughly West to East. None of them detonated and none fell onto inhabited areas.
In reverse order:
One fell under its parchute into the sea and was eventually recovered undamaged, with no contamination resulting.
One fell under its parachute into the area of the Almanzora river and was recovered undamaged, with no contamination resulting.
One fell north of Palomares, just beyond the old dairy on the edge of the village. It was damaged on impact and caused a limited amount radiation contamination in the immediate area of its impact.
One fell south of Palomares, in a small valley that is just to the south of the cemetary, facing (but nowhere near) Vera Playa. It was damaged on impact and caused slightly more radiation contamination in the immediate area of its impact.
There would have been no spread whatsoever of radiation, but for the initial attempts to clean up by the first American personelle on the spot, who proceeded to burn the effected vegetation. This resulted in extending the contamination, in each case, in a small plume in an easterly direction, down wind from the two impact sites. Fortunately, the wind strengths were modest and the process was stopped before the plumes reached any great distance or any habitation.
Subsequently, the most contaminated surface soil was collected into barrels and shipped to a nuclear waste dump in Maryland in the States. Low level contaminated material was buried in the areas of impact. Since then the area has been monitored by equipment located at the impact sites and in Palomares itself; it is understood that there has been no reported incidence above recommended levels.
Hitherto, the two relevant impact areas were not even fenced off and remained in private hands. Nevertheless, it was reported recently that snails in the area of impact have been found with levels of contamination and this coupled with increased agricultural activity and some other development near, although not on the impact sites themselves, has resulted in the government finally taking action.
The sites, amounting to around 7 hectares in total, are being compulsorily purchased and are at this moment being fenced off. The intention being to clear all contamination above normal ambient levels. Once cleaned, the sites are to be returned to the Town Hall for public use. The Town Hall presently intends to create small exhibitions, explaining the events, on the impact sites.
As far as Desert Springs is concerned, it is about 1.25 km away, in northerly direction across a line of hills, another valley and a plateau, from the nearest impact site.
Nevertheless, a dependency of the Spanish Ministry of Education & Sciences, the Centre for Energy, Environmental and Technological Investigations (CIEMAT), was contracted to investigate and test samples from the intervening land, lying between the edge of the resort and the nearest impact site, before that land was purchased. The results showed that no radiation above ambient levels was present.
I hope this helps.
Stephen