* "Don't panic" - naval base commander says
* Thousands of dependents could be affected - Pentagon
* Unclear which bases will be covered by Pentagon order
(Adds figures on eligibility, paragraph 3)
By Phil Stewart
WASHINGTON, March 17 The Pentagon on Thursday
announced plans for a voluntary evacuation of U.S. military
families from Japan's Honshu island amid growing anxiety about
radiation leaking from a crippled nuclear power plant.
Pentagon spokesman Colonel Dave Lapan said the order would
apply to thousands of dependents of U.S. military personnel at
bases on Japan's biggest island, a massive undertaking that
could involve the use of military aircraft if needed.
A spokesman for U.S. forces in Japan estimated that around
20,000 dependents would be eligible.
There are more than a dozen U.S. military bases and
facilities on Honshu, including two naval bases where families
were told this week to limit outdoor activity and shut off
external ventilation after low-level radiation was detected.
"Don't panic," Captain Eric Gardner, the commanding officer
at Naval Air Facility Atsugi, about 150 miles (241 km) from the
Fukushima nuclear plant, said in a video-message for
"It (the voluntary evacuation) is unprecedented ... instead
of the plan where those Americans in Korea would come to Japan,
now we're just doing it in reverse."
The United States on Wednesday showed increasing alarm
about Japan's nuclear crisis and urged its citizens to stay
clear of the Fukushima nuclear plant, going further in its
warnings than the Japanese government. [ID:nN16169392]
Even as the U.S. military ramps up a massive relief effort,
it is also creating new restrictions meant to safeguard troops
from the effects of radiation -- including by declaring a
50-mile (80-km) no-go zone for troops around the Fukushima
plant and preventatively prescribing medication for radiation.
Some U.S. air crews took potassium iodide tablets ahead of
missions that were within 70 miles (113 km) of the plant on
Wednesday, the Pentagon said.
Potassium iodide tablets were also being shipped to Japan
for troops, if needed.
Potassium iodide can saturate the thyroid gland and prevent
the uptake of radioactive iodine. When given before or shortly
after exposure, it can reduce risk of cancer in the long term.
Lapan said the voluntary evacuation would occur first by
commercial or chartered aircraft, like those the U.S. State
Department is using for its much smaller potential group of
Gardner said Air Force planes would also fly out family
members in what he described as a "military-assisted voluntary
departure." But Lapan said they would only be used if there was
sufficient demand among families.
Some of the U.S. bases on Honshu are well beyond the range
of radiation, like the Marine Corps' Air Station Iwakuni, and
it was unclear how many families would chose to participate in
the voluntary evacuation.
"We're talking potentially thousands of people. It's all
based on the volume," Lapan said.
"If there's a need for military aircraft then it will be
there. But the first options are the existing commercial and
charter aircraft capabilities."
(Editing by Paul Simao and Eric Beech)