Just before midnight, Japan time, north east Honshu got hit with the biggest “aftershock” yet, between 7.1 and 7.4.

At first there were tsunami warnings, but they were canceled when it was realized it was not the type of quake that would cause tsunami. But this latest quake puts another nuclear plant in trouble.

Onagawa nuke plant, in Miyagi Prefecture, was already struggling to keep itself cool using outside power. According to NHK this latest quake cut three of the two power lines running to the plant. There are some confusing reports as to how the plant is keeping its reactors cool; NHK says Onagawa is using power from one external electrical line. Reuters says Onagawa is running off back up generators.

The Japanese Nuclear and Industrial Safety Agency is rushing to confirm the status of the plant.

NHK interviewed a nuclear analyst, who pointed out that just because contamination readings are within safe limits does not mean that it’s ‘OK’.

He said officials are mistaken for telling people that it does not pose a threat to health. What it means is that you must begin “…limiting your exposure…” to radiation contamination, because it builds up in your body, it doesn’t go away.

It is referred to as cumulative exposure to radiation.

Japanese central government officials are now saying that they goofed on the evacuation zone currently in place.

Officials say the current evacuation zone is based on a short term, low level, nuclear emergency. They did not expect the current situation to have lasted so long.

Japanese officials say they will revise evacuation plans to take into account long term exposure to high levels of radiation.

Many local governments have given up relying on central government data, and have started their own evacuation plans.

”I feel very sorry that a local government had to decide on its own. As soon as possible, the government and…nuclear experts working together must present clear guidelines on from where to where is safe.”-Chief Cabinet Secretary Yukio Edano

In a 06 April 2011 Reuters article they compare an explosion of a reactor core, to the explosion of the reactor buildings three weeks ago:  “The possibility of another hydrogen explosion like those that ripped through reactors 1 and 3 early in the crisis, spreading high levels of radiation into the air, was ‘extremely low’, he said.”

This statement is completely misleading. It makes it sound like an explosion of the reactor core wont be any worse the the earlier explosions of the reactor buildings. Reuters does cite Tokyo Electric Power Company officials as the source of this misleading info.

If TEPCo is saying a reactor core explosion isn’t that bad then they are flat lying. If a reactor core explodes it will release a constant stream of deadly radiation, much worse than what is happening now!

It is possible that the TEPCo official was simply saying he thought the chance of an explosion was low (just an explosion), not that the chance of another explosion with resulting spewing of radiation was low. But that’s how the Reuters article reads. However TEPCo now has a proven track record of lying to the public.

In any case, don’t let anybody fool you, a reactor core explosion is THE worst case scenario, for a reason!

French nuclear analysts have used radiation numbers, publicly release by Japanese officials, to determine how bad the contamination is in the Pacific Ocean.

The Institute for Radiological Protection and Nuclear Safety determined that with the current level of contamination (that is the contamination that has already happened) fish and seaweed will need constant monitoring. Also, they said the high levels of radioactive contamination, recently spilled by reactor 2, will spread through out the Pacific Ocean in three months.

They pointed out that some radiation will float with the ocean currents, while other isotopes will sink to the ocean floor.  The ocean does not affect isotope half life, so cesium-137 still has a half life of 30 years in water.  Cesium-137 is in the ocean.

This does not assume any further contamination, so expect it to get worse.