0 a ring-shaped island formed of coral (= rock-like natural substance) that surrounds a lagoon (= area of sea water): --
the Bikini Atoll
The main source of supply was surface water accumulated over a very long period below the atoll.
The underground method which they have chosen has far greater environmental dangers to that atoll than if they had chosen atmospheric tests.
Probably most important is the protection the reefs give to the coast, particularly the coasts of atolls or other small islands.
Let us suppose that a bad egg slips through the net and is installed as governor of one of our few remaining imperial atolls.
But we may be wholly underestimating the future importance of many of these apparently insignificant and remote atolls.
Precautions would be taken if an airfield were built on the atoll.
Apart from anything else, those who cause explosions in coral atolls had better be careful what they do.
I believe that research is taking place already on some of these atolls in connection with the production of fertilisers.
