U.S. sub leaked radioactive water, possibly for months

Water with trace amounts of radioactivity may have leaked for months from a U.S. Navy nuclear-powered submarine as it traveled around the Pacific to ports in Guam, Japan and Hawaii, Navy officials told CNN on Friday.

Officials say the radiation leaked from the USS Houston, seen in this undated photo, was virtually undetectable.

The leak was found on the USS Houston, a Los Angeles-class fast attack submarine, after it went to Hawaii for routine maintenance last month, Navy officials said.

Navy officials said the amount of radiation leaked into the water was virtually undetectable. But the Navy alerted the Japanese government because the submarine had been docked in Japan.

The problem was discovered last month when a build-up of leaking water popped a covered valve and poured onto a sailor’s leg while the submarine was in dry dock.

An investigation found a valve was slowly dripping water from the sub’s nuclear power plant. The water had not been in direct contact with the nuclear reactor, Navy officials said.

Officials with knowledge of the incident could not quantify the amount of radiation leaked but insisted it was “negligible” and an “extremely low level.” The total amount leaked while the sub was in port in Guam, Japan and Hawaii was less than a half of a microcurie (0.0000005 curies), or less than what is found in a 50-pound bag of lawn and garden fertilizer, the officials said.

The sailor who was doused, a Houston crew member, tested negative for radiation from the water, according to Navy officials.