Daniel Snow, head man of the sparsely populated atoll in the Tuamotu archipelago, relates it as an ironic commentary on the antics of the French in the South Pacific. "It happened on Niau Island near here," he says. "A few years ago the French decided to build a lighthouse there. It was a fine tower with a powerful light, and on the last day all they had to do was take off the covers and start the machinery.
"The workers were just getting into their truck one morning when there was a big flash in the sky and a terrible noise from far away, like thunder. When they got to the lighthouse, which was far from the village, it was in ruins. Not one stone left standing.
"Of course, they knew it was an atomic test and they laughed, but they were lucky. Can you imagine if they had been on the top when the bomb went off? The best is, the French engineers got medals because nobody was injured building the lighthouse. That's the French for you."
Daniel and his friends still smile at the unforeseen consequence of a nuclear test in the early 1970s above Mururoa at the southern end of the Tuamotus. But other islanders are less amused by last week's decision to resume underground tests at the atoll after a three-year halt.
Vociferous political opposition is again rallying round Oscar Timaru, leader of the pro-independence movement in Tahiti. However, it is muted by economic imperatives. For some Tahitians, the tests are a symbol of French arrogance and imperialism, but for others they are a welcome assurance of a return to work in an economy blighted by unemployment and inflation.
The dilemma is acute for one young Tahitian, who used to work for the Centre d'Experimentation du Pacifique as a labourer. While diving for pearl off Fangatau, another atoll used for atmospheric tests, he had seen fissures in the reef wall.
"The coral is wide open and the cracks are very deep," he says. "How can they say nothing bad can come from there? My heart tells me the tests are bad, but my head tells me a lot of island people with families to support depend on the CEP for a living."
The French Defence Ministry has consistently denied reports that Mururoa is breaking up and sinking under the shock of more than 100 explosions conducted since 1966. However, a joint director of the test centre admitted as long ago as 1984 that the atoll would be "unsuitable" for further use by the turn of the century. French defence experts suggested at the time that Mururoa could no longer support big blasts of around 100 kilotons.
This came as no surprise to Bengt Danielsson, an anthropologist and authority on Polynesian culture. Since settling in Tahiti in 1953, he has infuriated French authorities and delighted Greenpeace with his unremitting opposition to the tests.
The author of Mururoa Mon Amour, he was among the first to detect lethal fall-out from atmospheric tests conducted between 1966 and 1974. According to Danielsson, there was an abnormally high incidence of cancer among Polynesians working at Mururoa, many of whom were taken to military hospitals in France and returned in coffins.
In a recent interview, he recalled: "Scientists from New Zealand recorded radioactive fall-out throughout the Pacific after the atmospheric tests, but the French denied there was any in their islands.
"Are we to believe the particles acted in a patriotic manner and jumped over French Polynesia to other islands? The other possibility, of course, is that the French were lying."
The focus of this fear is a low-lying atoll 650 miles south-east of Tahiti, which looks from the air like a necklace floating improbably on an azure sea. On closer inspection, it is a bizarre blend of heaven and hell.
Imagine a tropical moon shimmering on a placid lagoon, palm trees rustling in the trade winds - and a warren of subterranean caverns pulsating with radioactive debris. On the surface it is like a tourist's playground, with thatched huts and tennis courts nestling among hibiscus and bougainvillea; below it is a laboratory for mass destruction.
It snakes for about 40 miles around a lagoon in the shape of a shark's jaws, with one navigable entrance made hazardous by razor-sharp reefs. In effect a crown of coral perched above a dormant volcano, during a testing season it accommodates more than 1,000 scientists and technicians, 4,500 military personnel and up to 600 Polynesian workers in a complex of thatched huts and prefabricated cabins surrounded by air-conditioned offices and recreational facilities.
The illusion of a holiday resort is fostered by a slender red and white tower rising from the middle of the lagoon like a fairground helter-skelter. It is a service for lowering bombs and measuring apparatus into blast chambers deep in the basaltic rock of the volcano below.
The aftermath of the initial series of atmospheric tests is there for all to see. At the western extremities of the atoll, tangled vegetation gives way to a tortured landscape of incinerated palms and shattered coral, battered by huge waves, as if nature was trying to erase the evidence of military folly.
Shortly after French secret agents sabotaged the Rainbow Warrior in 1985, I was invited to an underground nuclear test at Mururoa. The bomb went off a mile away, but the earth hardly moved for us. It was a fairly small bomb in nuclear terms: probably barely big enough to incinerate Birmingham.
Gavin Bell writes for the `The Herald', Glasgow.Reuse content