YOKOSUKA NAVAL BASE, Japan — After her students left for the day, Karin Haug and other teachers gathered at the multipurpose room at Ikego Elementary School on March 17.

Shifting winds were blowing radiation from the damaged Fukushima Dai-ichi nuclear plant southward, they were told by school administrators who had spoken with Navy officials.

In five days, a radioactive plume would reach Yokosuka. Prepare to evacuate, they said.

No one was exactly sure of the threat, but words like “plume” and “evacuation” were enough to convince them that they were in serious danger.

“I went to call my family, told them I was being evacuated … and started crying,” Haug said. “I hugged my colleagues, because we really thought we might not see each other again.”

The plume from the plant did blow south on March 22. It briefly elevated levels of radioactive iodine in Tokyo tap water to unsafe levels for infants. But it never created a health hazard at Yokosuka, which is nearly 200 miles away from the damaged reactors.

Word of the potentially deadly threat from the plume was among the speculation, incomplete information and rumors that burrowed into commands and households at Yokosuka Naval Base after the devastating March 11 earthquake and tsunami.

Add hundreds of aftershocks, rapidly changing policies and the snap deployment of thousands of sailors aboard an aircraft carrier that had been practically disassembled, and what resulted was a recipe for boiling the understandable concern of the base’s 24,000 personnel into abject fear.

Befitting a military base, fear never turned into public disorder. Instead, anxiety began showing on the faces of friends, as they hugged each other goodbye before flying away on hastily booked commercial flights.

It mounted with nervous questions at town-hall meetings and demands for iodine pills on command-sponsored Facebook pages.

It became clear as parents fearing “another big one” kept children home from school. Attendance figures began plummeting the week before the military-assisted voluntary departure flights evacuating Yokosuka families to the United States.

Within a few days, about 3,000 of Yokosuka’s 6,700 family members had signed up for the military-assisted flights, which were announced March 17. About 4,500 would eventually leave, Yokosuka officials said.

A day of mixed messages

Radioactivity fears at Yokosuka dramatically rose on March 15 with news of the damaged reactors. The danger that sailors and their families perceived that day depended on the time, delivery and source of their information.

Shontelle Chavez came home from the grocery store that day and found a note on the doorstep of her Satsuki Heights base apartment, warning her to close her air vents because of radiation exposure. There was little explanation why, she said.

Despite the persistent earthquakes that she and her family had endured since March 11, Chavez said it wasn’t until receiving that notice that she truly got scared.

“The minute that letter came out, I thought, ‘Should I seriously be worried about my kids’ health?’ ” Chavez said. “A friend of mine said right then and there that she was leaving.”

Where that letter came from is still unclear. Commander Naval Forces Japan officials said they did not issue it. Last week, in an interview with Stars and Stripes, Yokosuka base commander Capt. David Owen said it was the first he had heard of it.

Chavez later noticed a short email sent at March 15 at 10:30 a.m. from the Anti-Terrorism Force Protection Ashore group, which said that low levels of non-threatening radioactivity had been found, but didn’t specify how much or provide an equivalent to an easily identifiable standard.

Chavez didn’t know that at 7 a.m., an hourly measurement of 1.5 millirems of radiation had been found at the USS George Washington’s pier. Twenty millirems were detected during the next 12 hours, according to Navy figures posted on the Yokosuka commander’s channel.

The figures later dropped to negligible levels above background radiation. In comparison, a mammogram delivers about 30 millirems of radiation, and a CT scan delivers a 1,100 millirem dose.

Rear Adm. Richard Wren, Naval Forces Japan commander, recommended that everyone stay indoors that morning, residents at Naval Air Facility Atsugi were told over loudspeakers.

The move made sense, according to Joseph G. Young, principal health physicist at Australian Radiation Services, in the absence of more information about the radioactivity’s composition, which had not been released by Naval Forces Japan.

In a broadcast later that day, Wren withdrew that recommendation but urged personnel to avoid outdoor activity: “There is no appreciable health risk, and we are being very conservative in our recommendations.”

Johanna Northshield, whose husband is deployed, became concerned when the spouse of a contractor who was part of “high-level command meetings” said they were planning on leaving for South Korea on March 16 because of the Fukushima reactor damage.

Northshield then saw cones being placed on roads, giving the appearance that large groups of people were about to be shepherded off base. Guards at the gates were wearing surgical masks — common on the streets in Japan, but rarely worn by servicemembers. With no explanation, people were left to draw their own conclusions, she said.

The next morning, Northshield and others received emails from ombudsmen — spouses appointed to relay their commands’ information to other families — that there would be a “voluntary evacuation.”

It would be several hours before defense officials made an official announcement that anyone would be leaving.

The evacuation order then changed from a priority for families whose spouses were deployed, to priority for spouses with infants. Then the evacuation became a “voluntary departure.”

“I didn’t know the difference between a voluntary departure and a mandatory evacuation,” Northshield said. “A lot of people didn’t know that. The information just changes non-stop, all the way to now.”

The servicemembers and officers on the base with informed perspective on nuclear power could have been inadvertently fueling the confusion. Wren, a former pilot, is one of several nuclear-trained officers at Yokosuka, and a majority of servicemembers at Yokosuka have worked on a nuclear-powered carrier or submarine. That would seem to make them more comfortable with the prospect of low-level radiation. Instead, multiple Navy officials told Stars and Stripes that it might have powered the nuclear rumor mill.

Sailors without any real nuclear knowledge might have heard an offhand remark from a “nuke,” the slang term for the Navy’s nuclear professionals, and passed on their own ideas.

“It’s not just what the nukes say,” said one Navy official who was not authorized to speak publicly, but observed Yokosuka over the past three weeks. “It’s all the people who know someone, who know someone, who then tell spouses that they need to get out of Dodge right away.”

The harbor empties

The abrupt departure of the USS George Washington prompted even more confusion, speculation and fear.

The aircraft carrier was scheduled to be in port and under maintenance until May, after having spent half of 2010 deployed.

“Every system was dismantled and undergoing routine maintenance and improvement when the earthquake struck,” according to a Facebook note from commanding officer Capt. David Lausman.

But on March 18, a steady stream of sailors toting luggage and sea bags starting making made their way down Nimitz Boulevard, leading many base residents to conclude that they were leaving to flee the radiation.

There was little to dissuade them. For operational security reasons, the Navy doesn’t announce ship deployments in advance. Rumors began spreading that the George Washington was going to load the ship with family members and whisk them to safety.

The George Washington did eventually leave, but not loaded with family members.

It left March 21 because even very-low level radiation would have registered on the ship’s ultrasensitive equipment and complicated its maintenance, officers told Stars and Stripes.

Pacific Command head Adm. Robert Willard elaborated at a March 23 town hall meeting at Yokosuka.

The USS Ronald Reagan had passed through the plume of radiation coming from the Fukushima nuclear reactor before repositioning to a safer area. It wasn’t health-threatening, but the ship nevertheless was scrubbed of radiation.

Willard said he moved the George Washington to avoid a similar situation.

“If radioactivity were to start accumulating on the flight deck or get down into the ventilation, it would make getting [George Washington] ready through the overhaul period harder and longer,” Willard said, according to a recording of the meeting. Stars and Stripes was barred from the meeting.

The George Washington’s departure, as well as the departure of about 75 percent of Yokosuka’s 9,000 servicemembers on ships, left a leadership void in the home for many families, Northshield said.

“I think a lot of the hysteria that was on base would have stopped if the partners were there to calm down the matter,” she said. “A lot of families left because their spouses weren’t there and it made it more difficult to cope.”

Still few answers

Despite all the flights and deployments, thousands of Japanese and American civilians, a smattering of family members and shore-assigned servicemembers remain at Yokosuka.

And they are still asking questions that, in the absence of definitive answers, create anxiety.

“Rumor control is our first and foremost battle,” said Owen, Yokosuka’s base commander. “And sometimes you take two steps forward, only to take one step back.”

The current rumors involve speculation on when the families and sailors will be returning, when a blackout might affect Yokosuka, and, of course, when the situation at Fukushima will improve.

None of those questions have answers right now, Owen said.

Owen doesn’t make policy decisions on those issues at his level, but says he tells people what he knows during daily broadcasts posted on the base Facebook page.

Until those answers come, the base will continue to get its services functioning, given its constraints on manpower and electricity use.

“It’s going to be a long time before you see this base back to normal,” he said.

slavine@pstripes.osd.mil

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