Erroneous readings at Fukushima Daiichi No. 2

TEPCO has reported some spikes in gas temperature readings and air conditioner (primary containment) temperature readings at Fukushima Daiichi No. 2 plant. These readings show some sharp increases, or in the case of the A/C plant a "stair step" increase. Some alarm may be generated in the public (and the press) if these are not properly interpreted.

-TEPCO has begun lowering the feed rates at all three plants in order to INCREASE the temperature of the reactor cores and thus the volume of cooling water in contact with them. This is being done to increase the amount of steam extant inside the pressure vessels to ensure that hydrogen trapped there cannot burn.

-The desire to lower the chance of hydrogen burn follows the discovery that hydrogen gas was indeed trapped inside the reactor vessel of No. 2 plant, with a maximum reading of 2.9%. TEPCO is altering its nitrogen feed plan at all three plants to give direct nitrogen purge to the pressure vessels, not just the primary containments. This new nitrogen feed is to be at twice the present rate.

-Given the lowering of feed rate to increase temperature and thus steam it follows that damaged cables / wires may be further damaged by the increase in moisture. Given this fact, TEPCO is investigating to determine the failure mode of the equipment that is giving errant readings. To be clear, there are other detectors that are NOT showing the same temperature increases, but rather are showing the expected gradual increase.

This set of facts is very likely to be misinterpreted by the press and deliberately misinterpreted by the anti-nuclear crowd. That's why I'm posting this explanation about the temperature increases, which are deliberate, and the reasons for this. Keep in mind that the APR Twitter feed noted the beginning of this operation as soon as it was announced; watch the Twitter feed for further updates.

4:28 PM Eastern Sunday November 27, 2011
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