Officially official: Fukushima a 5, matching 3-Mile Island accident.

Via Kyodo News, Japanese officials have updated the 4 rating on the Fukushima Daiichi incident to a 5, matching that of France's assessment, and it matches the rating of the 3-Mile Island accident in 1979.  So far, two days of shooting water, and the radiation levels are fluctuating, though not shooting up.

Meanwhile, according to the IAEA temperatures at reactor #5 and 6 appear to have risen slightly.  Temperature of spent fuel rods is supposed to be kept under 25°C.

Unit 4
13 March, 19:08 UTC:	84 °C
14 March, 10:08 UTC:	84 °C
15 March, 10:00 UTC:	84 °C
16 March, 05:00 UTC:	no data
Unit 5
14 March, 10:08 UTC:	59.7 °C
15 March, 10:00 UTC:	60.4 °C
16 March, 05:00 UTC:	62.7 °C
17 March, 03:00 UTC:	64.2 °C
17 March, 18:00 UTC:	65.5 °C
Unit 6
14 March, 10:08 UTC:	58.0 °C
15 March, 10:00 UTC:	58.5 °C
16 March, 05:00 UTC:	58.5 °C
17 March, 03:00 UTC:	62.5 °C
17 March, 18:00 UTC:	62.0 °C

According to Reuters, TEPCO officials understand that burying the reactors in concrete is their last option, but officials are hoping to connect and power up pumps at some reactors by Sunday, to get temperatures under control.  But what if they fail?  It's still not clear that the pumps will work -- seeing as the temperatures may have reached 1200°C (the melting point of the rod's casing, Zircaloy), many things would have failed under those temperatures, including plastics, rubber, and softer metals.


If power cannot be restored to the pumps, will TEPCO concurrently plan for a concrete sarcophagus while pursuing other means of slowing or stopping the meltdown of the fuel rods?  Or will they ignore the planning, and end up being caught unprepared, if things suddenly turn very bad?  Events of the past week suggests the latter might occur.


Note: LA Times has a new article citing a major fear by the US NRC and the Union of Concerned Scientists, that there is a breach in the spent fuel pool in reactor 4, and that the situation is only going to get worse.