France does not appear to have cleaned up the radioactive contamination around Reggane, after carrying out four explosions above ground and 12 underground tests. The first explosion, on 13 February 1960, was three times as powerful as the first American or British tests.
In authorising the test, General de Gaulle set back negotiations on a Comprehensive Nuclear Test Ban Treaty (CTBT), by breaking the moratorium that the three nuclear weapons states, the US, USSR and UK, had been observing since 1958. Diplomats hope that a CTBT may be achievable next year - 36 years after the French test.
The test had to be hurried for fear that the nuclear device might fall into the hands of terrorists: it took place just two weeks after elements of the French army in Algeria had mutinied. According to nuclear scientist Bertrand Goldschmidt: "Had the local army succeeded in taking over Algeria, it could have led to the first confrontation with an insurrectionist movement with a nuclear explosive device."
France's first underground test, some distance away in the mountains of Hoggar on 1 May 1962, was scarcely more auspicious. The explosion chamber leaked and radioactive vapour contaminated two French ministers witnessing the test.
The programme of atmospheric tests in Algeria provoked international outrage at the time. But the newly independent government of Algeria allowed France to continue its testing programme until 1966. A spokesman for the Algerian embassy in London said last week, "I seriously doubt if there have been any measures to clean the area up, but I can't be 100 per cent sure." The Commissariat l'Energie Atomique in Paris was unable to establish whether the sites had been cleaned up.
But one visitor to Reggane, Martin Bengtsson, recalls an area where the sand had been fused to glass, dotted with "Danger de mort" skull and crossbones signs. Mr Bengtsson, who was there in 1972, said: "There were a lot of sick people there who had either chosen to ignore the signs or couldn't read them." Some had deformed limbs and many "had white cataract eyes" which he now attributes to radiation. In the absence of a proper study it is impossible to be sure.