Читать книгу Meltdown - Yoichi Funabashi - Страница 15

At eight a.m. on March 12, Takako Tominaga (age 33), a doctor at the National Institute of Radiological Sciences (NIRS) located in Inage, Chiba, boarded an SDF helicopter. She was accompanied by two colleagues. The surrounding area was covered in high-voltage electrical power lines. Threading its way through the power lines, the helicopter headed to Fukushima.

Tominaga was an expert in emergency medicine. She had also worked for a year at the International Atomic Energy Agency (IAEA) in Vienna. She had been working for NIRS since 2009 and was a member of its Radiation Emergency Medical Assistance Team (REMAT), made up of emergency medical experts. On her jacket was the red REMAT logo against a navy, gray, and white background. She was wearing navy pants.

They were loaded up with measuring equipment, medical supplies, five hundred stable iodine tablets and forty boxes of Prussian blue. The stable iodine acts to lower levels of radioactive iodine, and the Prussian blue reduces the effect of radioactive exposure due to cesium.

Just before ten a.m., the helicopter landed in a baseball field near the offsite center. They were met by some NISA staff, but they could not open the fence, because it was locked. They climbed over the netting to get out. She had expected someone from the government or prefectural medical team to be there, but no one came.

The medical team on the second floor of the offsite center comprised the head of the Sousou Healthcare Center (South Soma), a liaison official from TEPCO, and a member of staff from the Japan Chemical Analysis Center. Tominaga joined them.

There was an initial radiation exposure medical facility nearby, namely the Ohno Prefectural Hospital (designated by the prefecture for Okuma Town, Futaba District). They heard that staff were still there accepting outpatients. When they checked it out, however, they found it was not functioning at all.

THE EVENING OF MARCH 12. An inquiry came in from Fukushima Daiichi that a worker had been exposed to “more than 100 millisieverts, what should we do?” The exact figure was 106.30 millisieverts. On further questioning, there did not seem to be an acute disorder.

“All you can do is get them to go to the emergency response center.”

A little later, the worker turned up.⁷⁷ He had been to the Ohno Hospital, but since there were no doctors there, he had come here. He said he was really worried. He was examined, but did not show any acute exposure symptoms, such as vomiting. It was likely that he was completely exhausted.

“Would you like to rest here?”

“No, I’ll go back to my post.”

They heard later that he was resting in the Anti-Seismic Building. The radiation levels of which were on the rise when venting.⁷⁸

The two colleagues who had flown in via helicopter with Tominaga were measurement specialists. They said dosage started to rise from four p.m. on March 12 into the night. This was a little after the Unit 1 explosion.

“The air dose rate indoors isn’t rising yet, but it’s climbing steadily outside.”

Contamination of the TEPCO, SDF, and police personnel traveling to Fukushima Daiichi and back was getting steadily worse. Five SDF officers came to the offsite center after they had finished pumping water, which took place before and after the explosion at Unit 1. While their levels were “normal” when measured onsite before they came, a screening test found 30,000 count per minute (cpm) before decontamination and 5,000–10,000 cpm after decontamination.⁷⁹

A screening test involves measuring the amount of radioactive material found on clothes or the body. Everyone had to be screened and decontaminated before entering the offsite center. The decontamination line was set at 600 cpm, but that meant everyone would be over it. Count per minute represented the amount of radiation measured in a minute. Since the type and strength of radiation cannot be measured, it was necessary to make different calculations according to the type of instrument in order to estimate the amount of radiation a person has suffered.

Where should the decontamination line be set? The Nuclear Emergency Plan was unclear on that point also. The medical team and monitoring teams got together and decided to set 40 becquerel/cm²—or, alternatively, 6,000 cpm—as the standard, which is the equivalent of the typical dosage received by Chernobyl workers who died within a month. They confirmed this with the NSC and NISA’s ERC and had a notification issued and sent to neighboring towns under the name of the local NERHQ director.

2:20 P.M., MARCH 13. Ikeda instructed the heads of Fukushima Prefecture, Okuma Town, Futaba Town, Tomioka Town, Namie Town, Naruha Town, Hirono Town, Katsurao Village, South Soma City, Kawauchi Village, and Tamura City that the screening level was to be set at 40 becquerel/cm²—or, alternatively, 6,000 cpm.

After issuing an order for residents to evacuate in a ten-kilometer radius in the early hours of March 12, people in the daycare centers and old people’s facilities in Futaba evacuated to Kawamata. Some of these were said to have been exposed to radiation while evacuating. They had to be screened. That job fell to Tominaga and her team.

“Please go to Kawamata.”

That was what they were told, but no one had any idea of where in Kawamata they were to go.

From the night of March 13 to the morning of March 14, Tominaga rode to Kawamata separately from her team in SDF trucks. On the way, the road was cut off by water. They were told it was too dangerous for the trucks and that they were to walk across. When they went to the police in Kawamata, no one knew who had evacuated to where. Guessing that they might learn something at the local gym, they headed there. They found the mayor of Futaba and his staff freezing in the sub-zero cold. They had fled with just the clothes on their backs. They had nothing to change into and their clothes were filthy.

They screened and decontaminated some eighty people from the town hall and daycare center. There were approximately a hundred people asleep in the adjacent building. They were all people who could not move on their own. They went there and screened them as well. Most of them were over 10,000 cpm. Their hair was up to 40,000–50,000 cpm. There were two people over 100,000 cpm.

Returning to the offsite center, they heard a thunderous noise as they were getting out of the truck. It was Unit 3 exploding. They hurried inside the building.

On the evening of March 14, the NIRS measurement experts identified cesium in their nuclide analysis of the airborne radioactive material.

“The core must be in meltdown.”

The fact that cesium had been found suggested that the fuel was melting and the containment vessel had been breached. The stable iodine they had brought quickly proved to be useful. Since the SDF unit that was carrying out the water pumping operations onsite at Fukushima Daiichi had not brought any with them, the medical team gave them enough for eight people.⁸⁰