Science Past from the issue of March 26, 1960

HIDDEN WATER TRACED BY BOMB FALLOUT IN RAIN — Radioactive fallout from atom bomb tests can be used to seek out and “expose” new sources of drinking water that lie hidden deep in the earth…. Raindrops have an affinity for absorbing minute particles of tritium from the fallout left in the atmosphere after nuclear bomb tests. Scientists seek ways to use these particles as “atomic dog tags” to identify underground water and find out how it percolates into the earth, where it goes and how fast it travels. This, they believe, may be done by taking samples from test wells at different places and depths from which water “tagged” with tritium can be identified with delicate instruments to learn its origin as rain or snow.