US Ambassador Roos issues statement on Japan’s ongoing nuclear emergency

The US Ambassador to Japan, John Roos issued the following statement on March 16, 2011, JPN time:

Today our hearts remain with our Japanese friends who, after suffering this devastating tragedy just four days ago, have to undertake recovery and reconstruction and address the ongoing nuclear emergency.

We understand that many of you are anxious and have questions in the shadow of the Fukushima emergency, since we are in the midst of a complex, constantly changing, and unpredictable situation. In this fluid situation, our commitment to our citizens is to accumulate accurate information and assess it sufficiently in order to make important judgments.

Since the first reports of trouble with the reactors, American nuclear experts have worked around the clock to analyze data, monitor developments, and provide clear assessments on the potential dangers. While at times we have had only limited access to information, I am personally committed to assuring that our experts have as much access and information as possible, and the necessary resources to understand the situation. I have personally been deeply engaged in these efforts.

After a careful analysis of data, radiation levels, and damage assessments of all units at Fukushima, our experts are in agreement with the response and measures taken by Japanese technicians, including their recommended 20 km radius for evacuation and additional shelter-in-place recommendations out to 30 km.

Let me also address reports of very low levels of radiation outside the evacuation area detected by U.S. and Japanese sensitive instrumentation. This bears very careful monitoring, which we are doing. If we assess that the radiation poses a threat to public health, we will share that information and provide relevant guidance immediately.

The United States will continue to work around the clock to provide precise and up-to-date information supported by expert analysis to ensure the safety and security of our citizens and to help Japan in its time of great need. U.S. citizens in need of emergency assistance should send an e-mail to with detailed information about their location and contact information, and monitor the U.S. Department of State website at

Bold italics added.  Check out US Embassy Japan’s page for current Warden Messages here.

Ambassador Roos on Twitter is here. ; but it looks like the tweets stopped on March 14.

The International Atomic Energy Agency update on 15 March 2011, 18:00 UTC confirmed the following status of the Fukushima Daiichi nuclear power plant:

  • Unit 4 was shut down for a routine, planned maintenance outage on 30 November 2010. After the outage, all fuel from the reactor was transferred to the spent fuel pool.
  • Units 5 and 6 were shut down at the time of the earthquake. Unit 5 was shut down as of 3 January 2011. Unit 6 was shut down as of 14 August 2010. Both reactors are currently loaded with fuel.
  • As of 00:16 UTC on 15 March, plant operators were considering the removal of panels from Units 5 and 6 reactor buildings to prevent a possible build-up of hydrogen in the future. It was a build-up of hydrogen at Units 1, 2 and 3 that led to explosions at the Daiichi facilities in recent days.

A later update on 15 March 2011, 20:35 UTC says that the Japanese government requested assistance from the IAEA in the areas of environmental monitoring and the effects of radiation on human health, asking for IAEA teams of experts to be sent to Japan to assist local experts. Also that preparations for these missions are currently under way.

The LA Times points out today that “neither Japanese officials with the Nuclear and Industrial Safety Agency nor experts with the United Nations’ International Atomic Energy Agency revised an earlier evaluation of the crisis at the Fukushima complex in northeast Japan that put the severity of the situation at 4 on the 7-point range of the International Nuclear and Radiological Event Scale.”

Apparently nuclear incidents are rated in a spectrum rates of levels 1-7. Level 1, meaning a minor problem with little human consequence, to Level 7, on the scale of the catastrophic Chernobyl nuclear accident 25 years ago.

LAT also quotes André-Claude LaCoste, president of the French nuclear safety agency saying, “It’s clear we are at Level 6.”

He said that level was akin to the 1979 crisis at Three Mile Island, the United States’ most serious nuclear incident, and only one degree below the 1986 catastrophe at Chernobyl, the northern Ukrainian nuclear complex where an explosion during a botched testing operation blew the roof off the reactor and released a radiation cloud that circled the Earth.

Nuclear authorities are reportedly concerned because the fuel rods in reactor No. 2 were at least partially exposed to the air for more than 14 hours, long enough for substantial melting to have occurred.

If you want to read more about the ABCs of Japan’s Nuclear Reactor Disaster, click here for an explanation from the Union of Concerned Scientists that includes what happens in a partial and complete meltdown.  It also has an explainer on the effect of radioactive materials on living tissues: 

The radioactive isotopes of greatest concern in a nuclear power accident are iodine-131 and cesium-137. Iodine-131 has a half-life of 8 days, meaning half of it will have decayed after 8 days, and half of that in another 8 days, etc. Therefore, it is of greatest concern in the days and weeks following an accident. It is also volatile so will spread easily.

In the human body, iodine is taken up by the thyroid, and becomes concentrated there, where it can lead to thyroid cancer in later life. Children who are exposed to iodine-131 are more likely than adults to get cancer later in life.

Cesium-137 has a half-life of about 30 years, so will take more than a century to decay by a significant amount. Living organisms treat cesium-137 as if it was potassium, and it becomes part of the fluid electrolytes and is eventually excreted. Cesium-137 is passed up the food chain. It can cause many different types of cancer.

Read more here.