The cores on all three reactors melted down. These are the events that caused these reactors to melt down:

The water in the containment vessel evaporated because the pumps that keep the coolant water flowing were disabled by the flooding waters of the tsunami.

The nuclear fuel became uncovered and heated up to a temperature of 2,300 degrees celsius.

The nuclear fuel melted and mixed with the materials in the containment vessel.

This melted core formed a magma called corium which flowed down to the bottom of the reactor vessel.

The corium pierced the containment vessel and fell on the concrete containment.

Currently we don’t know what quantity of corium has fallen and how deep did the corium pierce the concrete containment vessel!

Ohio Exopolitics: blogtalkradio.com/ohioexopolitics

Source: blogtalkradio.com/ohioexopolitics/2013/12/26/fukushima-round-table-discussion-2

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