US Navy investigation determines radiation leaks on US nuclear attack sub insignificant – but solicits input from environmental groups

US Navy

Publish date: August 14, 2008

Written by: Charles Digges

An American nuclear-powered submarine that leaked radiation for more than two years while touring the Pacific released the bulk of the material in its home port of Guam and at Hawaii’s Pearl Harbor and caused no threat to people or the environment, Japanese and U.S. officials said Wednesday.

Release of news earlier this month over the leak incident involving the USS Houston stung the US Navy, not only because the leak was so small, but because the United States had, until now, an unblemished record of never having released any radioactivity in port or at sea from any of its subs, US and international observers said.

“You could say this incident doesn’t even count, but I guess that would be dirty pool,” said a US Naval officer at Annapolis, the US Naval academy, in a telephone interview.

“Numbers are numbers no matter how small – it’s and embarrassing little snafu to break a winning streak with,” said the officer who requested anonymity as he is not authorized to speak about the incident

The US Navy over the weekend released a detailed chronology of the leaks for the USS Houston from June 2006 to July 2008, showing that the cumulative radiation released was less than 9.3 micro curies – with 8 micro curies released in Guam along.

By comparison, according to the US Environmental Protection Agency, the average amount of radioactivity in a smoke detector is about one micro curie, the Navy said in the report.

According to the Navy’s chronology, the USS Houston released 8 micro curies in its home port of Guam and .4 micro curies in Pearl Harbor. In addition to the leaks in Japan — a total of .605 micro curies at the three ports — the ship also released small amounts of radiation during port visits in Singapore, Port Kelang, Malaysia, and Saipan.

“At no time was there a risk to the reactor plant, the safety of the crew, the safety of the public, marine life, or the environment as a result of this port visit,” the US Navy said in the report.

“The amount of naturally occurring radioactivity in the seawater of a harbor is millions of times greater than the radioactivity released during this event.”

Japan supported these assertions in a statement it released along with the US Navy’s.

"If we add all radiation leaked at every Japanese port, it would be still smaller than the amount of naturally occurring radioactivity found inside home smoke detectors. Japan also has found no abnormality in its monitoring results during Houston’s port calls since June 2006," said the statement from the Japanese foreign Ministry.

USS Houston still in dry dock for ‘weepage’
Navy Commander Jeff Davis told the Associated Press that the Houston is still in Hawaii being repaired and the reactor is turned off. Once the leak was discovered last month, the Navy provided detailed data to the Knolls Atomic Power Laboratory — a US government military facility — to determine exactly how much radiation had leaked over the two year time period, Davis said.

The amount is so small, he said, that the Navy terms it a "weepage" rather than a leak. The problem was discovered on July 17th, when about a gallon of water spilled onto a crewmember when a fitting came loose. The water had previously come in contact with the reactor, but no radioactivity was detected on the sailor.

The Knolls Atomic Power Laboratory determined during its inquiry that a shut valve in the USS Houston’s engineering plant has been steadily leaking a small amount above the stringent design specification from 2006 until Houston was placed in dry dock in July 2008.

“This ‘weepage’ was so small that it was below the limit of detection by personnel on the ship and was indistinguishable by the ship from no leakage at all,” Naval press secretary Charles Reyes Jr. said.

More information requested from environmental watch dogs

Reyes said the US administration is interested in getting more information about the leak incident from any other source or any other party that may have more information, as so far the US Navy has been garnered only from the US Navy.

“Right now, the only major information that we received is from the US military. According to the military, there is no reason for alarm. So far, no environmental group has stepped forward to alert us to any other impacts,” the press secretary said.

Reyes noted that Japan, which was also affected by the leak and is a technologically advanced nation with technical expertise in the field of radiation detection, is apparently satisfied with the U.S. military’s report.

“Based on the news, Japan seems to be satisfied with the assurances given by the U.S. military and government. If Japan is satisfied [considering] they have much more technical expertise, much more resources, I think the (those other ports where the USS Houston) may be reasonably satisfied, unless we receive anything else to the contrary,” he added.

On Aug. 1st, the U.S. Navy notified Japan that the USS Houston had leaked water containing small amounts of radiation during three calls to the southern Japanese ports of Sasebo and Okinawa in March and April this year but caused no threat to people or the environment.

World’s only nuclear bomb victim sensitive to nuclear navy

Information about the radiation leak – coming on the eve of the anniversary of the Hiroshima bomb caused a stir in Japan where the continued presence of the US military and its nuclear vessels draw complaints from residents about crime, noise and pollution linked to some 50,000 American servicemen based in the country.

The presence of nuclear submarines is particularly sensitive, given that Japan is the only country the US ever used atomic bombs against in the closing days of World War II.

Information about the leak also followed on the heels of news that the diesel powered Kitty Hawk US aircraft carrier, which is stationed in Japan, will be replaced in September by the nuclear aircraft carrier, the USS George Washington. The announcement last month brought 10,000 people out onto the streets of Yokosuka in protest.